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The infinite-domain CSP dichotomy conjecture extends the finite-domain CSP dichotomy theorem to reducts of finitely bounded homogeneous structures. Every countable finitely bounded homogeneous structure is uniquely described by a universal first-order sentence up to isomorphism, and every reduct of such a structure by a sentence of the logic SNP. By Fraïssé’s Theorem, testing the existence of a finitely bounded homogeneous structure for a given universal first-order sentence is equivalent to testing the amalgamation property for the class of its finite models. The present paper motivates a complexity-theoretic view on the classification problem for finitely bounded homogeneous structures. We show that this meta-problem is EXPSPACE-hard or PSPACE-hard, depending on whether the input is specified by a universal sentence or a set of forbidden substructures. By relaxing the input to SNP sentences and the question to the existence of a structure with a finitely bounded homogeneous expansion, we obtain a different meta-problem, closely related to the question of homogenizability. We show that this second meta-problem is already undecidable, even if the input SNP sentence comes from the Datalog fragment and uses at most binary relation symbols. As a byproduct of our proof, we also get the undecidability of some other properties for Datalog programs, e.g., whether they can be rewritten in the logic MMSNP, whether they solve some finite-domain CSP, or whether they define a structure with a homogeneous Ramsey expansion in a finite relational signature.

The field of robotics has witnessed significant advancements in recent years, with robotic arms playing a pivotal role in various industrial and research applications. In large-scale manufacturing, manual labour has been replaced with robots due to their efficiency in time and cost. However, in order to replace human labour, the robots need to collaborate in a way that humans do. This master's thesis, conducted at the Cyber-physical Systems Lab (CPS-Lab) at Uppsala University, delves into the intricacies of cooperative interactions between two homogenous robotic arms powered by machine learning algorithms, aiming to explore their collective capabilities. The project will focus on implementing a multi-agent cart-pole experiment that will challenge the two robotic arms' cooperative abilities. First, the problem is simulated, and afterwards implemented in real life. The experiment will be evaluated by the performance of various tested machine learning algorithms. In the end, The simulation yielded poor results due to the complexity of the problem and the lack of proper hyperparameter tuning. The real life experiment failed instantly, caused by the robotic arms not being designed for this application, a large simulation gap, and latency in the controller design. Overall, the results show that the experiment was challenging for the robotic arms, but that it might be possible under different circumstances.

The field of robotics has witnessed significant advancements in recent years, with robotic arms playing a pivotal role in various industrial and research applications. In large-scale manufacturing, manual labour has been replaced with robots due to their efficiency in time and cost. However, in order to replace human labour, the robots need to collaborate in a way that humans do. This master's thesis, conducted at the Cyber-physical Systems Lab (CPS-Lab) at Uppsala University, delves into the intricacies of cooperative interactions between two homogenous robotic arms powered by machine learning algorithms, aiming to explore their collective capabilities. The project will focus on implementing a multi-agent cart-pole experiment that will challenge the two robotic arms' cooperative abilities. First, the problem is simulated, and afterwards implemented in real life. The experiment will be evaluated by the performance of various tested machine learning algorithms. In the end, The simulation yielded poor results due to the complexity of the problem and the lack of proper hyperparameter tuning. The real life experiment failed instantly, caused by the robotic arms not being designed for this application, a large simulation gap, and latency in the controller design. Overall, the results show that the experiment was challenging for the robotic arms, but that it might be possible under different circumstances.

[Abstract] We determine all three-dimensional homogeneous and 1 -curvature homogeneous Lorentzian metrics which are critical for a quadratic curvature functional. As a result, we show that any quadratic curvature functional admits different non-Einstein homogeneous critical metrics and that there exist homogeneous metrics which are critical for all quadratic curvature functionals without being Einstein.

We introduce a new variant of Chubanov's method for solving linear homogeneous systems with positive variables. In the Basic Procedure we use a recently introduced cut in combination with Nemirovski's Mirror-Prox method. We show that the cut requires at most (Formula presented.) time, just as Chubanov's cut. In an earlier paper it was shown that the new cuts are at least as sharp as those of Chubanov. Our Modified Main Algorithm is in essence the same as Chubanov's Main Algorithm, except that it uses the new Basic Procedure as a subroutine. The new method has (Formula presented.) time complexity, where (Formula presented.) is a suitably defined condition number. As we show, a simplified version of the new Basic Procedure competes well with the Smooth Perceptron Scheme of Peña and Soheili and, when combined with Rescaling, also with two commercial codes for linear optimization., Optimization

Many drugs cannot be made without homogeneous catalysis. To increase the yield of drug synthesis, the search for new catalysts continues. Computational catalysis is becoming a more prominent tool since it en- ables to screen many catalysts without performing (m)any laboratory experiments. In this research a com- putational workflow has been created to calculate both electronic (e.g. dipole, ionisation potential, nucle- ophilicity, etc.) and steric (bite angle, buried volume, cone angle, etc.) molecular descriptors. The structures were automatically created starting from the metal centre, some bidentate phosphorus ligands, auxiliary lig- ands, and the substrate. An in-house computational workflow, MACE, is used for for high-throughput gen- eration of structures from the starting bidentate phosphorus ligands, by generating stereo-isomers around to metal centre. Afterwards small substituents (H, CH3, Ph, etc.) are changed by ChemSpaX increasing the number of structures combinatorically. To reduce the computational cost of this workflow, it has been re- searched whether properties of the octahedral geometry could be predicted using properties from a simple model structure containing only the metal centre and the bidentate phosphorus ligand. This model structure did not show a correlation except for the electronic energy and the solvent accessible surface area, which are both primarily influenced by the number of electrons. Other correlations may be found if some other descriptors were calculated which where excluded now, like the HOMO-LUMO gap and the substrate bind- ing energy. The workflow could be extended to machine learning and improved by including symmetry and optical isomerism., Molecular Science and Technology

To combat the increasing energy demand and climate change, artificial photosynthesis is a promising approach to producing renewables by storing energy into chemicals and fuels. Water oxidation, responsible for offering electrons and protons to the reduction reactions, suffers from slow kinetics. Consequently, developing highly efficient water oxidation catalysts (WOCs) reacting via desirable mechanisms plays an essential role in reaching the goal of artificial photosynthesis. Molecular WOCs in homogeneous catalysis could serve as models to understand the structure-property relationship and the reaction mechanisms owing to their well-defined structures and easily characterized properties. In Chapter 1, a variety of Ru- and Fe-based molecular WOCs are introduced. The two catalytic mechanisms for the O-O bond formation, water nucleophilic attack (WNA) and interaction of two metal-oxos (I2M), are described in Chapter 1. To understand the catalytic mechanisms for designing better WOCs, various theoretical techniques have been applied. Density functional theory (DFT) method was used to study the molecular properties of catalysts and the reaction energetics. Molecular dynamics (MD) and potential of mean force (PMF) were employed to investigate the behavior of catalysts and to calculate the free energy change along a specific coordinate in the explicit solvent. The theory for computing redox potentials, acid dissociation constants, reaction rate constants, and the descriptions of different solvation models are presented in Chapter 2. The family of Ru(bda)(py)2 (bda2- denotes 2,2'-bipyridine-6,6'-dicarboxylate, py denotes pyridine) complexes exhibits extremely high catalytic activity via the I2M mechanism under acidic conditions. Extensive studies have previously been conducted on the primary and secondary coordination environments. In Chapter 3, the first section focuses on three different modifications on the para-sites of the two pyridines. It is found that the complex wi, För att bekämpa den ökande energiefterfrågan och klimatförändringarna är artificiell fotosyntes ett lovande tillvägagångssätt för att producera förnybara energikällor genom att lagra energi i kemikalier och bränslen. För att tillhandahålla elektroner och protoner till reduktionsreaktionerna oxideras vatten, en reaktion som lider av långsam kinetik. Följaktligen spelar utveckling av högeffektiva vattenoxidationskatalysatorer (WOC) som reagerar via önskvärda mekanismer en viktig roll för att nå målet med artificiell fotosyntes. Molekylära WOCs i homogen katalys kan fungera som modeller för att förstå struktur-egenskapsförhållandet och reaktionsmekanismerna på grund av deras väldefinierade strukturer och lätt karakteriserade egenskaper. I kapitel 1 introduceras Ru- och Fe-baserade molekylära WOCs. De två katalytiska mekanismerna för O-O-bindningsbildning, nukleofil attack av vatten (WNA) och interaktion mellan två metalloxointermediärer (I2M), beskrivs i kapitel 1. För att förstå de katalytiska mekanismerna för att designa bättre WOCs, har olika teoretiska tekniker använts. Täthetsfunktionalteori (DFT) användes för att studera de molekylära egenskaperna hos katalysatorer och reaktionsenergierna. Molekyldynamik (MD) och potential of mean force (PMF) användes för att undersöka beteendet hos katalysatorer och för att beräkna den fria energiförändringen längs en specifik koordinat i explicita lösningsmedel. Teorin för beräkning av redoxpotentialer, syradissociationskonstanter, reaktionshastighetskonstanter och beskrivningarna av olika solvatiseringsmodeller presenteras i kapitel 2. Familjen Ru(bda)(py)2 (bda2- betecknar 2,2'-bipyridin-6,6'-dikarboxylat, py betecknar pyridin) komplex uppvisar extremt hög katalytisk aktivitet via I2M-mekanismen under sura förhållanden. Omfattande studier har tidigare gjorts kring de primära och sekundära koordinationssfärerna. I kapitel 3 fokuserar det första avsnittet på tre olika modifieringar av parapositionerna hos de två pyridinerna. De, QC 2022-05-05

Syftet med denna undersökning är att rikta fokus mot skillnader i samarbete i könshomogena och könsheterogena grupper samt hur dessa skillnader kan tänkas påverka elevers läsförståelse. Genom en kvalitativ undersökning observerades 33 elever i nio grupperingar i årskurs 2 och 3 i svenska grundskolan. Undersökningens empiri insamlades genom observationer och transkriberade ljudfiler från när eleverna samarbetade i könsheterogena och könshomogena grupper. En abduktiv innehållsanalys med en socialkonstruktivistisk ansats genomfördes på insamlad empiri. Resultatet som uppkom i analys och diskussion i relation till tidigare forskning pekar på att det finns skillnader mellan könshomogena och könsheterogena grupper i relation till samarbetsmönster, diskussioner och ledarskapsförmåga. Kommunikation mellan eleverna visade sig vara en avgörande del i hur samarbetet fortlöpte och hur konstruktiva samtalen kring det givna ämnet blev. Flickor påvisade en mer direkt kommunikation med auktoritära drag i kontrast till pojkar som visade en större betoning på kollektiv tillhörighet och att befästa ny kunskap tillsammans. I relation till läsförståelse visar resultatet att elevernas kommunikation och individuella förmågor kopplat till läsförståelse påverkade samarbetet och förståelsen för innehållet.

To combat the increasing energy demand and climate change, artificial photosynthesis is a promising approach to producing renewables by storing energy into chemicals and fuels. Water oxidation, responsible for offering electrons and protons to the reduction reactions, suffers from slow kinetics. Consequently, developing highly efficient water oxidation catalysts (WOCs) reacting via desirable mechanisms plays an essential role in reaching the goal of artificial photosynthesis. Molecular WOCs in homogeneous catalysis could serve as models to understand the structure-property relationship and the reaction mechanisms owing to their well-defined structures and easily characterized properties. In Chapter 1, a variety of Ru- and Fe-based molecular WOCs are introduced. The two catalytic mechanisms for the O-O bond formation, water nucleophilic attack (WNA) and interaction of two metal-oxos (I2M), are described in Chapter 1. To understand the catalytic mechanisms for designing better WOCs, various theoretical techniques have been applied. Density functional theory (DFT) method was used to study the molecular properties of catalysts and the reaction energetics. Molecular dynamics (MD) and potential of mean force (PMF) were employed to investigate the behavior of catalysts and to calculate the free energy change along a specific coordinate in the explicit solvent. The theory for computing redox potentials, acid dissociation constants, reaction rate constants, and the descriptions of different solvation models are presented in Chapter 2. The family of Ru(bda)(py)2 (bda2- denotes 2,2'-bipyridine-6,6'-dicarboxylate, py denotes pyridine) complexes exhibits extremely high catalytic activity via the I2M mechanism under acidic conditions. Extensive studies have previously been conducted on the primary and secondary coordination environments. In Chapter 3, the first section focuses on three different modifications on the para-sites of the two pyridines. It is found that the complex wi, För att bekämpa den ökande energiefterfrågan och klimatförändringarna är artificiell fotosyntes ett lovande tillvägagångssätt för att producera förnybara energikällor genom att lagra energi i kemikalier och bränslen. För att tillhandahålla elektroner och protoner till reduktionsreaktionerna oxideras vatten, en reaktion som lider av långsam kinetik. Följaktligen spelar utveckling av högeffektiva vattenoxidationskatalysatorer (WOC) som reagerar via önskvärda mekanismer en viktig roll för att nå målet med artificiell fotosyntes. Molekylära WOCs i homogen katalys kan fungera som modeller för att förstå struktur-egenskapsförhållandet och reaktionsmekanismerna på grund av deras väldefinierade strukturer och lätt karakteriserade egenskaper. I kapitel 1 introduceras Ru- och Fe-baserade molekylära WOCs. De två katalytiska mekanismerna för O-O-bindningsbildning, nukleofil attack av vatten (WNA) och interaktion mellan två metalloxointermediärer (I2M), beskrivs i kapitel 1. För att förstå de katalytiska mekanismerna för att designa bättre WOCs, har olika teoretiska tekniker använts. Täthetsfunktionalteori (DFT) användes för att studera de molekylära egenskaperna hos katalysatorer och reaktionsenergierna. Molekyldynamik (MD) och potential of mean force (PMF) användes för att undersöka beteendet hos katalysatorer och för att beräkna den fria energiförändringen längs en specifik koordinat i explicita lösningsmedel. Teorin för beräkning av redoxpotentialer, syradissociationskonstanter, reaktionshastighetskonstanter och beskrivningarna av olika solvatiseringsmodeller presenteras i kapitel 2. Familjen Ru(bda)(py)2 (bda2- betecknar 2,2'-bipyridin-6,6'-dikarboxylat, py betecknar pyridin) komplex uppvisar extremt hög katalytisk aktivitet via I2M-mekanismen under sura förhållanden. Omfattande studier har tidigare gjorts kring de primära och sekundära koordinationssfärerna. I kapitel 3 fokuserar det första avsnittet på tre olika modifieringar av parapositionerna hos de två pyridinerna. De, QC 2022-05-05

Large-scale groundwater models are required to estimate groundwater availability and to inform water management strategies on the national scale. However, parameterization of large-scale groundwater models covering areas of major river basins and more is challenging due to the lack of observational data and the mismatch between the scales of modeling and measurements. In this work, we propose to bridge the scale gap and derive regional hydraulic parameters by spectral analysis of groundwater level fluctuations. We hypothesize that specific locations in aquifers can reveal regional parameters of the hydraulic system. We first generate ensembles of synthetic but realistic aquifers which systematically differ in complexity. Applying Liang and Zhang’s (2013) semi-analytical solution for the spectrum of hydraulic head time series, we identify for each ensemble member and at different locations representative aquifer parameters. Next, we extend our study to investigate the use of spectral analysis in more complex numerical models and in real settings. Our analyses indicate that the variance of inferred effective transmissivity and storativity values for stochastic aquifer ensembles is small for observation points which are far away from the Dirichlet boundary. Moreover, the head time series has to cover a period which is roughly ten times as long as the characteristic time of the aquifer. In deterministic aquifer models we infer equivalent, regionally valid parameters. A sensitivity analysis further reveals that as long as aquifer length and position of the groundwater location is roughly known, the parameters can be robustly estimated.

Syftet med denna undersökning är att rikta fokus mot skillnader i samarbete i könshomogena och könsheterogena grupper samt hur dessa skillnader kan tänkas påverka elevers läsförståelse. Genom en kvalitativ undersökning observerades 33 elever i nio grupperingar i årskurs 2 och 3 i svenska grundskolan. Undersökningens empiri insamlades genom observationer och transkriberade ljudfiler från när eleverna samarbetade i könsheterogena och könshomogena grupper. En abduktiv innehållsanalys med en socialkonstruktivistisk ansats genomfördes på insamlad empiri. Resultatet som uppkom i analys och diskussion i relation till tidigare forskning pekar på att det finns skillnader mellan könshomogena och könsheterogena grupper i relation till samarbetsmönster, diskussioner och ledarskapsförmåga. Kommunikation mellan eleverna visade sig vara en avgörande del i hur samarbetet fortlöpte och hur konstruktiva samtalen kring det givna ämnet blev. Flickor påvisade en mer direkt kommunikation med auktoritära drag i kontrast till pojkar som visade en större betoning på kollektiv tillhörighet och att befästa ny kunskap tillsammans. I relation till läsförståelse visar resultatet att elevernas kommunikation och individuella förmågor kopplat till läsförståelse påverkade samarbetet och förståelsen för innehållet.

To combat the increasing energy demand and climate change, artificial photosynthesis is a promising approach to producing renewables by storing energy into chemicals and fuels. Water oxidation, responsible for offering electrons and protons to the reduction reactions, suffers from slow kinetics. Consequently, developing highly efficient water oxidation catalysts (WOCs) reacting via desirable mechanisms plays an essential role in reaching the goal of artificial photosynthesis. Molecular WOCs in homogeneous catalysis could serve as models to understand the structure-property relationship and the reaction mechanisms owing to their well-defined structures and easily characterized properties. In Chapter 1, a variety of Ru- and Fe-based molecular WOCs are introduced. The two catalytic mechanisms for the O-O bond formation, water nucleophilic attack (WNA) and interaction of two metal-oxos (I2M), are described in Chapter 1. To understand the catalytic mechanisms for designing better WOCs, various theoretical techniques have been applied. Density functional theory (DFT) method was used to study the molecular properties of catalysts and the reaction energetics. Molecular dynamics (MD) and potential of mean force (PMF) were employed to investigate the behavior of catalysts and to calculate the free energy change along a specific coordinate in the explicit solvent. The theory for computing redox potentials, acid dissociation constants, reaction rate constants, and the descriptions of different solvation models are presented in Chapter 2. The family of Ru(bda)(py)2 (bda2- denotes 2,2'-bipyridine-6,6'-dicarboxylate, py denotes pyridine) complexes exhibits extremely high catalytic activity via the I2M mechanism under acidic conditions. Extensive studies have previously been conducted on the primary and secondary coordination environments. In Chapter 3, the first section focuses on three different modifications on the para-sites of the two pyridines. It is found that the complex wi, För att bekämpa den ökande energiefterfrågan och klimatförändringarna är artificiell fotosyntes ett lovande tillvägagångssätt för att producera förnybara energikällor genom att lagra energi i kemikalier och bränslen. För att tillhandahålla elektroner och protoner till reduktionsreaktionerna oxideras vatten, en reaktion som lider av långsam kinetik. Följaktligen spelar utveckling av högeffektiva vattenoxidationskatalysatorer (WOC) som reagerar via önskvärda mekanismer en viktig roll för att nå målet med artificiell fotosyntes. Molekylära WOCs i homogen katalys kan fungera som modeller för att förstå struktur-egenskapsförhållandet och reaktionsmekanismerna på grund av deras väldefinierade strukturer och lätt karakteriserade egenskaper. I kapitel 1 introduceras Ru- och Fe-baserade molekylära WOCs. De två katalytiska mekanismerna för O-O-bindningsbildning, nukleofil attack av vatten (WNA) och interaktion mellan två metalloxointermediärer (I2M), beskrivs i kapitel 1. För att förstå de katalytiska mekanismerna för att designa bättre WOCs, har olika teoretiska tekniker använts. Täthetsfunktionalteori (DFT) användes för att studera de molekylära egenskaperna hos katalysatorer och reaktionsenergierna. Molekyldynamik (MD) och potential of mean force (PMF) användes för att undersöka beteendet hos katalysatorer och för att beräkna den fria energiförändringen längs en specifik koordinat i explicita lösningsmedel. Teorin för beräkning av redoxpotentialer, syradissociationskonstanter, reaktionshastighetskonstanter och beskrivningarna av olika solvatiseringsmodeller presenteras i kapitel 2. Familjen Ru(bda)(py)2 (bda2- betecknar 2,2'-bipyridin-6,6'-dikarboxylat, py betecknar pyridin) komplex uppvisar extremt hög katalytisk aktivitet via I2M-mekanismen under sura förhållanden. Omfattande studier har tidigare gjorts kring de primära och sekundära koordinationssfärerna. I kapitel 3 fokuserar det första avsnittet på tre olika modifieringar av parapositionerna hos de två pyridinerna. De, QC 2022-05-05

To combat the increasing energy demand and climate change, artificial photosynthesis is a promising approach to producing renewables by storing energy into chemicals and fuels. Water oxidation, responsible for offering electrons and protons to the reduction reactions, suffers from slow kinetics. Consequently, developing highly efficient water oxidation catalysts (WOCs) reacting via desirable mechanisms plays an essential role in reaching the goal of artificial photosynthesis. Molecular WOCs in homogeneous catalysis could serve as models to understand the structure-property relationship and the reaction mechanisms owing to their well-defined structures and easily characterized properties. In Chapter 1, a variety of Ru- and Fe-based molecular WOCs are introduced. The two catalytic mechanisms for the O-O bond formation, water nucleophilic attack (WNA) and interaction of two metal-oxos (I2M), are described in Chapter 1. To understand the catalytic mechanisms for designing better WOCs, various theoretical techniques have been applied. Density functional theory (DFT) method was used to study the molecular properties of catalysts and the reaction energetics. Molecular dynamics (MD) and potential of mean force (PMF) were employed to investigate the behavior of catalysts and to calculate the free energy change along a specific coordinate in the explicit solvent. The theory for computing redox potentials, acid dissociation constants, reaction rate constants, and the descriptions of different solvation models are presented in Chapter 2. The family of Ru(bda)(py)2 (bda2- denotes 2,2'-bipyridine-6,6'-dicarboxylate, py denotes pyridine) complexes exhibits extremely high catalytic activity via the I2M mechanism under acidic conditions. Extensive studies have previously been conducted on the primary and secondary coordination environments. In Chapter 3, the first section focuses on three different modifications on the para-sites of the two pyridines. It is found that the complex wi, För att bekämpa den ökande energiefterfrågan och klimatförändringarna är artificiell fotosyntes ett lovande tillvägagångssätt för att producera förnybara energikällor genom att lagra energi i kemikalier och bränslen. För att tillhandahålla elektroner och protoner till reduktionsreaktionerna oxideras vatten, en reaktion som lider av långsam kinetik. Följaktligen spelar utveckling av högeffektiva vattenoxidationskatalysatorer (WOC) som reagerar via önskvärda mekanismer en viktig roll för att nå målet med artificiell fotosyntes. Molekylära WOCs i homogen katalys kan fungera som modeller för att förstå struktur-egenskapsförhållandet och reaktionsmekanismerna på grund av deras väldefinierade strukturer och lätt karakteriserade egenskaper. I kapitel 1 introduceras Ru- och Fe-baserade molekylära WOCs. De två katalytiska mekanismerna för O-O-bindningsbildning, nukleofil attack av vatten (WNA) och interaktion mellan två metalloxointermediärer (I2M), beskrivs i kapitel 1. För att förstå de katalytiska mekanismerna för att designa bättre WOCs, har olika teoretiska tekniker använts. Täthetsfunktionalteori (DFT) användes för att studera de molekylära egenskaperna hos katalysatorer och reaktionsenergierna. Molekyldynamik (MD) och potential of mean force (PMF) användes för att undersöka beteendet hos katalysatorer och för att beräkna den fria energiförändringen längs en specifik koordinat i explicita lösningsmedel. Teorin för beräkning av redoxpotentialer, syradissociationskonstanter, reaktionshastighetskonstanter och beskrivningarna av olika solvatiseringsmodeller presenteras i kapitel 2. Familjen Ru(bda)(py)2 (bda2- betecknar 2,2'-bipyridin-6,6'-dikarboxylat, py betecknar pyridin) komplex uppvisar extremt hög katalytisk aktivitet via I2M-mekanismen under sura förhållanden. Omfattande studier har tidigare gjorts kring de primära och sekundära koordinationssfärerna. I kapitel 3 fokuserar det första avsnittet på tre olika modifieringar av parapositionerna hos de två pyridinerna. De, QC 2022-05-05

To combat the increasing energy demand and climate change, artificial photosynthesis is a promising approach to producing renewables by storing energy into chemicals and fuels. Water oxidation, responsible for offering electrons and protons to the reduction reactions, suffers from slow kinetics. Consequently, developing highly efficient water oxidation catalysts (WOCs) reacting via desirable mechanisms plays an essential role in reaching the goal of artificial photosynthesis. Molecular WOCs in homogeneous catalysis could serve as models to understand the structure-property relationship and the reaction mechanisms owing to their well-defined structures and easily characterized properties. In Chapter 1, a variety of Ru- and Fe-based molecular WOCs are introduced. The two catalytic mechanisms for the O-O bond formation, water nucleophilic attack (WNA) and interaction of two metal-oxos (I2M), are described in Chapter 1. To understand the catalytic mechanisms for designing better WOCs, various theoretical techniques have been applied. Density functional theory (DFT) method was used to study the molecular properties of catalysts and the reaction energetics. Molecular dynamics (MD) and potential of mean force (PMF) were employed to investigate the behavior of catalysts and to calculate the free energy change along a specific coordinate in the explicit solvent. The theory for computing redox potentials, acid dissociation constants, reaction rate constants, and the descriptions of different solvation models are presented in Chapter 2. The family of Ru(bda)(py)2 (bda2- denotes 2,2'-bipyridine-6,6'-dicarboxylate, py denotes pyridine) complexes exhibits extremely high catalytic activity via the I2M mechanism under acidic conditions. Extensive studies have previously been conducted on the primary and secondary coordination environments. In Chapter 3, the first section focuses on three different modifications on the para-sites of the two pyridines. It is found that the complex wi, För att bekämpa den ökande energiefterfrågan och klimatförändringarna är artificiell fotosyntes ett lovande tillvägagångssätt för att producera förnybara energikällor genom att lagra energi i kemikalier och bränslen. För att tillhandahålla elektroner och protoner till reduktionsreaktionerna oxideras vatten, en reaktion som lider av långsam kinetik. Följaktligen spelar utveckling av högeffektiva vattenoxidationskatalysatorer (WOC) som reagerar via önskvärda mekanismer en viktig roll för att nå målet med artificiell fotosyntes. Molekylära WOCs i homogen katalys kan fungera som modeller för att förstå struktur-egenskapsförhållandet och reaktionsmekanismerna på grund av deras väldefinierade strukturer och lätt karakteriserade egenskaper. I kapitel 1 introduceras Ru- och Fe-baserade molekylära WOCs. De två katalytiska mekanismerna för O-O-bindningsbildning, nukleofil attack av vatten (WNA) och interaktion mellan två metalloxointermediärer (I2M), beskrivs i kapitel 1. För att förstå de katalytiska mekanismerna för att designa bättre WOCs, har olika teoretiska tekniker använts. Täthetsfunktionalteori (DFT) användes för att studera de molekylära egenskaperna hos katalysatorer och reaktionsenergierna. Molekyldynamik (MD) och potential of mean force (PMF) användes för att undersöka beteendet hos katalysatorer och för att beräkna den fria energiförändringen längs en specifik koordinat i explicita lösningsmedel. Teorin för beräkning av redoxpotentialer, syradissociationskonstanter, reaktionshastighetskonstanter och beskrivningarna av olika solvatiseringsmodeller presenteras i kapitel 2. Familjen Ru(bda)(py)2 (bda2- betecknar 2,2'-bipyridin-6,6'-dikarboxylat, py betecknar pyridin) komplex uppvisar extremt hög katalytisk aktivitet via I2M-mekanismen under sura förhållanden. Omfattande studier har tidigare gjorts kring de primära och sekundära koordinationssfärerna. I kapitel 3 fokuserar det första avsnittet på tre olika modifieringar av parapositionerna hos de två pyridinerna. De, QC 2022-05-05

We introduce a new variant of Chubanov's method for solving linear homogeneous systems with positive variables. In the Basic Procedure we use a recently introduced cut in combination with Nemirovski's Mirror-Prox method. We show that the cut requires at most (Formula presented.) time, just as Chubanov's cut. In an earlier paper it was shown that the new cuts are at least as sharp as those of Chubanov. Our Modified Main Algorithm is in essence the same as Chubanov's Main Algorithm, except that it uses the new Basic Procedure as a subroutine. The new method has (Formula presented.) time complexity, where (Formula presented.) is a suitably defined condition number. As we show, a simplified version of the new Basic Procedure competes well with the Smooth Perceptron Scheme of Peña and Soheili and, when combined with Rescaling, also with two commercial codes for linear optimization., Discrete Mathematics and Optimization

Many drugs cannot be made without homogeneous catalysis. To increase the yield of drug synthesis, the search for new catalysts continues. Computational catalysis is becoming a more prominent tool since it en- ables to screen many catalysts without performing (m)any laboratory experiments. In this research a com- putational workflow has been created to calculate both electronic (e.g. dipole, ionisation potential, nucle- ophilicity, etc.) and steric (bite angle, buried volume, cone angle, etc.) molecular descriptors. The structures were automatically created starting from the metal centre, some bidentate phosphorus ligands, auxiliary lig- ands, and the substrate. An in-house computational workflow, MACE, is used for for high-throughput gen- eration of structures from the starting bidentate phosphorus ligands, by generating stereo-isomers around to metal centre. Afterwards small substituents (H, CH3, Ph, etc.) are changed by ChemSpaX increasing the number of structures combinatorically. To reduce the computational cost of this workflow, it has been re- searched whether properties of the octahedral geometry could be predicted using properties from a simple model structure containing only the metal centre and the bidentate phosphorus ligand. This model structure did not show a correlation except for the electronic energy and the solvent accessible surface area, which are both primarily influenced by the number of electrons. Other correlations may be found if some other descriptors were calculated which where excluded now, like the HOMO-LUMO gap and the substrate bind- ing energy. The workflow could be extended to machine learning and improved by including symmetry and optical isomerism., Molecular Science and Technology, Applied Physics

Three parameters of thermal environment, varied calculated shear correction, and third-order shear deformation theory (TSDT) of displacement are important in the frequency study. These three effects have been studied on the non-dimensional and dimensional frequencies of thick FGM plates. An additional c1 displacement term in nonlinear coefficient of TSDT is used to present the frequency of vibration into the simply homogeneous equation of thick FGM plates. The determinant of the coefficient matrix containing the c1 displacement term in dynamic differential equilibrium equations can be derived into the five degree polynomial free vibration equation. The non-dimensional and dimensional of natural frequency can be obtained. The effects of plate thickness, temperature of environment and power law index of FGM on the non-dimensional and dimensional frequency of FGM plates are investigated. &nbsp

In the present paper, an homogeneous and non-homogeneous inverse problem constrained by the stationary problem in electrocardiology representing the heart, lungs surfaces, and torso model is investigated. Our goal is to reconstruct the electrical potentials on the surface of the heart from the information obtained non invasively on the torso surface. The existence and uniqueness of solution for the heart-torso problem and the related inverse problem is assessed, and the primal and dual problems are discretized using a finite element method. We present some preliminary numerical experiments using an efficient implementation of the proposed scheme in homogeneous and non-homogeneous cases. Finally, we demonstrate the effect of the non-homogeneity on the reconstructed epicardial potential and show that the inverse ECG problem cannot be solved by the classical BEM (boundary element method).

Syfte – Denna studie undersöker hur verksamma lärare i årskurs 1–3 undervisar i religionskunskap om världsreligionerna, kristendom, islam och judendom i mångkulturella och homogena klasser i svenska skolor. Syftet med studien är att undersöka om det finns skillnader i undervisningen mellan de två olika elevgrupperna, samt vilka faktorer som påverkar lärares val av undervisningsinnehåll. Ur ett lärarperspektiv ska denna studie dessutom öka insikten över hur lärare påverkas och utformar sin världsreligionsundervisning utifrån olika elevsammansättningar. Metod och teori– Undersökningen genomfördes med hjälp av en webbenkät som innehöll 26 frågor med varierande svarsalternativ. Enkäten består av två delar, bakgrundsfrågor samt frågor om religionsundervisningen och besvarades av 103 respondenter. Den insamlade empirin undersöks utifrån ramfaktorteorin. Resultat – De huvudsakliga resultaten visar att skillnaden mellan mångkulturella och homogena elevgrupper är liten. Det finns dock en skillnad i hur mycket uppmärksamhet högtiderna gavs i de olika religionerna mellan elevgrupperna. Läroplanen anses vara den faktorn som styr religionsundervisningen i högsta grad då resultatet visar att lärarna utgår från den när de planerar sin undervisning. Avslutningsvis diskuteras resultatet i relation till den tidigare forskningen och ramfaktorteorin., Purpose – This study examines how active teachers in grades 1-3 teach religious studies about world religions, Christianity, Islam and Judaism, in multicultural and homogeneous classes in Swedish schools. The purpose of the study is to examine whether there are differences in teaching between the two different groups of students, as well as the factors influencing choice of teaching content. From a teacher's perspective, this study will also increase insight into how teachers are affected and thereby designing their world religious teaching based on different student compositions. Method and theory– The survey was conducted using an online survey that includes 26 questions with varying response options. The survey consists of two parts: background questions; and questions about religious education and was answered by 103 respondents. The collected empirics is analyzed based on the framework factor theory. Results – The main results show that the difference between multicultural and homogeneous groups of pupils is insignificant. However, there was a difference in how much attention the religious holidays were given in the different religions between the student groups. The curriculum is considered to be the factor that governs religious education to the highest degree as the results show that teachers start from it when planning their teaching. Finally, the results are discussed in relation to the previous research and framework factor theory.

Syfte – Denna studie undersöker hur verksamma lärare i årskurs 1–3 undervisar i religionskunskap om världsreligionerna, kristendom, islam och judendom i mångkulturella och homogena klasser i svenska skolor. Syftet med studien är att undersöka om det finns skillnader i undervisningen mellan de två olika elevgrupperna, samt vilka faktorer som påverkar lärares val av undervisningsinnehåll. Ur ett lärarperspektiv ska denna studie dessutom öka insikten över hur lärare påverkas och utformar sin världsreligionsundervisning utifrån olika elevsammansättningar. Metod och teori– Undersökningen genomfördes med hjälp av en webbenkät som innehöll 26 frågor med varierande svarsalternativ. Enkäten består av två delar, bakgrundsfrågor samt frågor om religionsundervisningen och besvarades av 103 respondenter. Den insamlade empirin undersöks utifrån ramfaktorteorin. Resultat – De huvudsakliga resultaten visar att skillnaden mellan mångkulturella och homogena elevgrupper är liten. Det finns dock en skillnad i hur mycket uppmärksamhet högtiderna gavs i de olika religionerna mellan elevgrupperna. Läroplanen anses vara den faktorn som styr religionsundervisningen i högsta grad då resultatet visar att lärarna utgår från den när de planerar sin undervisning. Avslutningsvis diskuteras resultatet i relation till den tidigare forskningen och ramfaktorteorin., Purpose – This study examines how active teachers in grades 1-3 teach religious studies about world religions, Christianity, Islam and Judaism, in multicultural and homogeneous classes in Swedish schools. The purpose of the study is to examine whether there are differences in teaching between the two different groups of students, as well as the factors influencing choice of teaching content. From a teacher's perspective, this study will also increase insight into how teachers are affected and thereby designing their world religious teaching based on different student compositions. Method and theory– The survey was conducted using an online survey that includes 26 questions with varying response options. The survey consists of two parts: background questions; and questions about religious education and was answered by 103 respondents. The collected empirics is analyzed based on the framework factor theory. Results – The main results show that the difference between multicultural and homogeneous groups of pupils is insignificant. However, there was a difference in how much attention the religious holidays were given in the different religions between the student groups. The curriculum is considered to be the factor that governs religious education to the highest degree as the results show that teachers start from it when planning their teaching. Finally, the results are discussed in relation to the previous research and framework factor theory.

This article explains modal aesthetics concept. The theoretical frame is expound by different authors who defend aesthetics behaviour in human beings and their skills making art. Human experience is beauty if they establish a relation with the materia from the ontological and honest position and in regards to make an organic interaction to transform each other. Human and materia would reach an homogeneous status because of the effective knowledge (from ontological research) and experience will let they understand the nature of subject and object. This theory is contrasted with Teresa Lanceta’s work. Lanceta shows us a deep respect to the object and culture. Her work claims the emotion and the particular artist expression from an homogeneous relation with the object., El presente documento explica el concepto de la estética modal. Para ello se elabora un marco teórico a través de distintos autores, los cuales defienden la capacidad creadora del ser humano y la necesidad de otorgar un sentido estético que dote de belleza la experiencia del ser en este mundo. Experimentamos este modelo de belleza desde el conocimiento sincero del otro, desde una relación que respeta la naturaleza misma de las cosas y donde la transformación surge de la interacción orgánica entre ambas. Este modelo de relación sucede desde un plano homogéneo entre sus participantes, los cuales, tras la experiencia y la investigación ontológica, consiguen transmutar su naturaleza. El análisis busca contrastar el modelo teórico con la obra de la artista Teresa Lanceta. Ella, a través de su dilatada experiencia y estilo artístico, ha puesto de manifiesto un profundo respeto hacia la materia con la que trabaja y a la cultura con la que interactúa. Su obra se convierte en la reivindicación de la emoción y la identificación de la individualidad que se recoge en la expresión del sujeto creador que establece una relación homogénea con el objeto.

CeO_2-ZrO_2 composite nanoparticles with mesoporous and spherical morphologies were assembled into different homogeneously dispersed, domain, and core-shell structures by changing the reaction conditions, such as the heating rate, acid, and solvent, in supercritical alcohols. Ce_xZr_<1−x>O_2 with homogeneous structures were prepared from Ce(NO_3)_3 and ZrO(NO_3)_2 in the presence of formic acid in methanol by rapid heating (500℃/min) to 300℃, while CeO_2–ZrO_2 with domain structures were obtained by slow heating (5.4℃/min). Treatment of mesoporous and spherical ZrO_2 nanoparticles with a Ce(NO_3)_3 solution in supercritical conditions yielded CeO_2-ZrO_2 nanocomposites with core-shell morphologies, while solvents playing a key role in controlling the thickness of the outer shell; methanol produced a very thin outer shell (<1 nm) of cubic CeO_2 and 2-propanol afforded a thick outer shell (100-200 nm) of cubic CeO_2.

This article explains modal aesthetics concept. The theoretical frame is expound by different authors who defend aesthetics behaviour in human beings and their skills making art. Human experience is beauty if they establish a relation with the materia from the ontological and honest position and in regards to make an organic interaction to transform each other. Human and materia would reach an homogeneous status because of the effective knowledge (from ontological research) and experience will let they understand the nature of subject and object. This theory is contrasted with Teresa Lanceta’s work. Lanceta shows us a deep respect to the object and culture. Her work claims the emotion and the particular artist expression from an homogeneous relation with the object., El presente documento explica el concepto de la estética modal. Para ello se elabora un marco teórico a través de distintos autores, los cuales defienden la capacidad creadora del ser humano y la necesidad de otorgar un sentido estético que dote de belleza la experiencia del ser en este mundo. Experimentamos este modelo de belleza desde el conocimiento sincero del otro, desde una relación que respeta la naturaleza misma de las cosas y donde la transformación surge de la interacción orgánica entre ambas. Este modelo de relación sucede desde un plano homogéneo entre sus participantes, los cuales, tras la experiencia y la investigación ontológica, consiguen transmutar su naturaleza. El análisis busca contrastar el modelo teórico con la obra de la artista Teresa Lanceta. Ella, a través de su dilatada experiencia y estilo artístico, ha puesto de manifiesto un profundo respeto hacia la materia con la que trabaja y a la cultura con la que interactúa. Su obra se convierte en la reivindicación de la emoción y la identificación de la individualidad que se recoge en la expresión del sujeto creador que establece una relación homogénea con el objeto.

An experimental investigation of turbulence kinetic energy in the nearly homogeneous and isotropic region of a moderate intensity flow ($12\%$), with the Taylor Reynolds number varying between 175 and 540, generated by an active grid for nominal mean velocities of \Ams allows for an assessment of the applicability of the power decay law. A combination of single and cross hot-wires probes the flow to determine important flow quantities. The cross-wire in particular has a limited calibration range requiring the flow angles to fall within $\pm 33^{\circ}$. This occurs for, at the nominal velocities of 4, 6, 8 and 12 $m \, s^{-1}$, are at $x/M_U$ of 60, 75, 80 and 95, respectively. By comparing the velocity power spectrum in the downstream, the cross stream and in the vertical direction leads to conclusion that the turbulence is isotropic starting in pseudo inertial subrange. Using Kolmogorov (1941) normalization supports local isotropy with the collapse of the high wavenumber range. An additional power law is derived analytically for nearly homogenous, isotropic turbulence that relates the turbulence kinetic energy to the dissipation rate. The typical decay power law requires determining the location of the virtual origin via assumption or some other method. The selection of different virtual origins leads to differing decay exponents. The derived power law relationship allows for the determination of the decay exponent independently from the virtual origin. In deriving a power decay law in homogenous isotropic turbulence it is assumed that the normalized dissipation rate, $C_{\epsilon ,q}$, is constant. $C_{\epsilon ,q}$ is within $5\%$ of the asymptotic value for 6, 8 and 12 \ms from 75 to 142, 80 to 142 and 95 to 142 mesh lengths downstream of the active grid, respectively. $C_{\epsilon ,q}$ is within $15\%$, for 4 \ms, for the downstream locations of 60 to 110. The decay exponents obtained from the turbulence kinetic energy, the dissipation rate and the derived pow

Herein, we report a highly efficient iron-catalyzed intramolecular nucleophilic cyclization of alpha-allenols to furnish substituted 2,3-dihydrofurans under mild reaction conditions. A highly diastereoselective variant of the reaction was developed as well, giving diastereomeric ratios of up to 98:2. The combination of the iron-catalyzed cycloisomerization with enzymatic resolution afforded the 2,3-dihydrofuran in high ee. A detailed DFT study provides insight into the reaction mechanism and gives a rationalization for the high chemo-and diastereoselectivity.

This work presents a look-up table method to compute the thermodynamic properties of CO2. It is motivated by the massive employment of this fluid in the industrial domain, especially in the ejector-expansion cycle. Computational Fluid Dynamics (CFD) simulations have been used in the past to investigate two-phase ejector flows. CO2 exhibits then large property variations due to phase transition. As a result, it cannot be accurately modelled by a general analytical Equation of State (EoS), such as Peng-Robinson EoS and Perfect gas EoS, etc. Hence, a tabulated EoS is developed here based on the Span-Wagner (EoS), covering the temperature range from 217 to 800 K and pressures up to 50 MPa. Supercritical, liquid, vapor and liquid-vapor states are all included in this tabulated EoS. Besides, the density and the internal energy are chosen as two independent inputs to compute the other properties. The method is designed to be coupled with the system of equations in its conservative form which is a usual formulation for compressible solvers. Through two validation cases, the proposed tabulated EoS shows good performances in terms of accuracy and efficiency, making it suitable for future massive CFD simulations.

This work presents a look-up table method to compute the thermodynamic properties of CO2. It is motivated by the massive employment of this fluid in the industrial domain, especially in the ejector-expansion cycle. Computational Fluid Dynamics (CFD) simulations have been used in the past to investigate two-phase ejector flows. CO2 exhibits then large property variations due to phase transition. As a result, it cannot be accurately modelled by a general analytical Equation of State (EoS), such as Peng-Robinson EoS and Perfect gas EoS, etc. Hence, a tabulated EoS is developed here based on the Span-Wagner (EoS), covering the temperature range from 217 to 800 K and pressures up to 50 MPa. Supercritical, liquid, vapor and liquid-vapor states are all included in this tabulated EoS. Besides, the density and the internal energy are chosen as two independent inputs to compute the other properties. The method is designed to be coupled with the system of equations in its conservative form which is a usual formulation for compressible solvers. Through two validation cases, the proposed tabulated EoS shows good performances in terms of accuracy and efficiency, making it suitable for future massive CFD simulations.

A practical homogeneous and gas-liquid palladium-catalyzed Catellani-type reaction using a continuous-flow platform is described. The implementation of continuous-flow technology allowed the acceleration of the transformation and, for the first time, expansion of the chemical space to gaseous olefins (i.e., ethylene, propylene and 3,3,3-trifluoropropene), thus providing a safe and practical approach to sterically hindered ortho-disubstituted styrenes and vinyl arenes. The complete control over the stoichiometry of gaseous reagents through flow technology proved essential for directing the selectivity of the Catellani reaction to the desired products.

An experimental investigation of turbulence kinetic energy in the nearly homogeneous and isotropic region of a moderate intensity flow ($12\%$), with the Taylor Reynolds number varying between 175 and 540, generated by an active grid for nominal mean velocities of \Ams allows for an assessment of the applicability of the power decay law. A combination of single and cross hot-wires probes the flow to determine important flow quantities. The cross-wire in particular has a limited calibration range requiring the flow angles to fall within $\pm 33^{\circ}$. This occurs for, at the nominal velocities of 4, 6, 8 and 12 $m \, s^{-1}$, are at $x/M_U$ of 60, 75, 80 and 95, respectively. By comparing the velocity power spectrum in the downstream, the cross stream and in the vertical direction leads to conclusion that the turbulence is isotropic starting in pseudo inertial subrange. Using Kolmogorov (1941) normalization supports local isotropy with the collapse of the high wavenumber range. An additional power law is derived analytically for nearly homogenous, isotropic turbulence that relates the turbulence kinetic energy to the dissipation rate. The typical decay power law requires determining the location of the virtual origin via assumption or some other method. The selection of different virtual origins leads to differing decay exponents. The derived power law relationship allows for the determination of the decay exponent independently from the virtual origin. In deriving a power decay law in homogenous isotropic turbulence it is assumed that the normalized dissipation rate, $C_{\epsilon ,q}$, is constant. $C_{\epsilon ,q}$ is within $5\%$ of the asymptotic value for 6, 8 and 12 \ms from 75 to 142, 80 to 142 and 95 to 142 mesh lengths downstream of the active grid, respectively. $C_{\epsilon ,q}$ is within $15\%$, for 4 \ms, for the downstream locations of 60 to 110. The decay exponents obtained from the turbulence kinetic energy, the dissipation rate and the derived pow

Thermal stresses are calculated in thick-walled circular cylinder under internal and external pressure. The concept of transition theory and generalized strain measures is employed for the creep analysis of thick-walled cylinder. The mathematical modelling details of the methodology applied in this analysis are discussed extensively. Analytical method of solution has been applied to simplify the governing differential equations. The obtained results are presented in terms of graphs. On the basis of analysis, it has been deduced that less compressible thick-walled circular cylinder with thermal effects under the influence of internal and external pressure with non-linear measure is a better alternative for design engineers as compared to other cylinders.

A practical homogeneous and gas-liquid palladium-catalyzed Catellani-type reaction using a continuous-flow platform is described. The implementation of continuous-flow technology allowed the acceleration of the transformation and, for the first time, expansion of the chemical space to gaseous olefins (i.e., ethylene, propylene and 3,3,3-trifluoropropene), thus providing a safe and practical approach to sterically hindered ortho-disubstituted styrenes and vinyl arenes. The complete control over the stoichiometry of gaseous reagents through flow technology proved essential for directing the selectivity of the Catellani reaction to the desired products.

Cooperative learning is a proven teaching strategy that teachers have been using for over 40 years. Teachers often group students heterogeneously so that students that are lower achieving are learning from higher achieving students and higher achieving students support and solidify their learning by restating and re-teaching to their lower achieving partners. The purpose of this study was to test homogeneous and heterogeneous grouping while using cooperative learning teaching structure. This dissertation aimed to answer the question, should students be grouped homogeneously or heterogeneously while participating in cooperative learning. The research design for this study was quantitative, quasi-experimental. A convenience sample of fifth-grade students was drawn from a Georgia Christian elementary school in the 2017-2018 school year. The data were analyzed using paired and unpaired T-test. The independent samples t-test was run to compare the scores from the FOSS Survey/Posttest, and the analysis showed no significant difference between the homogeneous and heterogeneous posttest scores. Both groups made significant gains, however in this study the grouping did not have a significant impact on the difference in posttest scores for the two groups.

To solve the problem of determining the flame temperature in the working space of the thermal units it is proposed to calculate the change of adiabatic enthalpy by using methods of probability theory. It is shown that the normal function of the fuel cells distribution allows to obtain the integral function of enthalpy and adiabatic temperature along the length of flame distribution, including at asymmetrical distribution function. The problem is solved regarding homogeneous diffusive gaseous flames, associated with the combustion of sprayed liquid fuel. Transfer equations solutions regularization’s conditions are defined, homochronic number and Bio mass transfer number relation’s approximations are proposed. For synthesis of the solution on canals of initial forms the corresponding linear connections are proposed; the limits of change of the mass transfer Bio number and the convergence of series sums in the regularization of solutions of the surface combustion equation are defined according to the method of Burke-Schumann. Flame length’s dispersion factor’s variability is considered. The explanation of the S-shaped temperature curve observed by the burning of nearly all fuels in installations of various types is proposed. Flame processes generally examined by probability theory with various density of normal distribution function φ(U) for homogenic flame by normal integral function Ф(U) are described. The steady form Ф(U) significantly explains the S-shaped longitudinal temperature function observed in practice and which serves as a basis for thermal and non-stationary theory of ignition. Actual flame’s temperature determination is possible on flare’s continuum adiabatic temperature placement taking into account the radiative properties of all heat transfer system’s elements. Likewise the task of heterogenic flame’s axial temperature’s description with variable dispersion factor σ can be solved. © 2017, National University of Science and Technology MISIS. All rights

We study the heterogeneous wireless sensor networks (WSNs) and propose the necessary condition of the optimal sensor deployment. Similar to that in homogeneous WSNs, the necessary condition implies that every sensor node location should coincide with the centroid of its own optimal sensing region. Moreover, we discuss the dynamic sensor deployment in both the homogeneous and the heterogeneous WSNs with limited communication range for the sensor nodes. The purpose of sensor deployment is to improve sensing performance, reflected by distortion and coverage. We model the sensor deployment problem as a source coding problem with distortion reflecting sensing accuracy. However, when the communication range is limited, a WSN is divided into several disconnected sub-graphs under certain conditions as we will discuss in this paper. In such a scenario, neither the conventional distortion nor the coverage represents the sensing performance as the collected data in disconnected sub-graphs cannot be communicated with the access point. By defining an appropriate sensing performance measure, we propose a Restrained Lloyd (RL) algorithm and a deterministic annealing (DA) algorithm to optimize sensor deployment in both the homogeneous and heterogeneous WSNs. Our simulation results show that both the DA and the RL algorithms outperform the existing algorithms when communication range is limited.

Group composition is common in education and is fairly well examined at a school level but not within competence development in a working environment. How should a group of coworkers be grouped when attending a course? This can be a complicated question, especially at a big company such as Atlas Copco which has employees from all over the world. The main object with this report is to find which aspects has to be taken into account when putting people together in groups at a multinational company and secondly give a proposal to Atlas Copco for how the groups should be constructed in the company. The data collected for this report was gathered mostly during the two focus group discussions that were held by the researchers. This material was complemented with interviews held before and after the focus groups meetings, to get a more profound picture of the company. The outcome of the interviews and discussions were then compared with relevant literature on the subject, to be able to make an analysis on the important factors. Findings from the analysis shows that language and previous knowledge are limiting factors and should therefore determine if a person is allowed to attend a certain course. The more knowledge the course participants have in the subject and how well the participants understand the spoken language, the more information exchange will occur between the teacher and course participants. Geographical cultural differences were found to have a slight importance when designing groups but not so significant that special action has to be taken. Combining or keeping separate departments apart during a course were found to be a question on whether or not the different subcultures at the company could be mixed or not. In this case the informants in the research believed it was more beneficial for the company to mix, to prevent the subcultures to grow in separate ways. The conclusion is that the most important aspect of a group constellation are the language and pr, Gruppsammansättningens betydelse är en omdiskuterad företeelse som är vanligt förekommande i utbildningssammanhang och är relativt väl utforskat på skolnivå men inte när det gäller kompetensutveckling inom arbetslivet. Hur ska en gruppsammansättning av arbetskamrater se ut vid ett kurstillfälle? Det kan vara en komplicerad fråga, speciellt på ett stort företag som Atlas Copco vilka har anställda över hela världen. Huvudsyftet med denna rapport är att finna vilka aspekter som behöver tas hänsyn till när folk blir sammansatta i grupper i multinationella företag och ge förslag till Atlas Copco hur grupperingen ska genomföras inom företaget. Data för denna rapport insamlades mestadels under två fokusgruppsdiskussioner som hölls av forskarna. Som komplement till detta material hölls intervjuer både före och efter fokusgruppsmötena för att få en bredare inblick i företaget. Resultatet från intervjuerna och diskussionerna jämfördes sedan med relevant litteratur för att analysera de viktiga faktorerna. Resultat av analysen visar att språkkunskaper och tidigare kunskap i ämnet behöver vara begränsande faktorer vid bestämmandet om en person tillåts närvara vid specifika kurser. Om en person inte har tillräcklig kunskap i språket kursen hålls i, sker inget lyckat informationsutbyte mellan lärare och kursdeltagare och samma gäller aspekten med tidigare kunskap. Geografiskt kulturella skillnader visades vara av ringa betydelse vid designande av grupper men inte så viktiga att det behövs vidtas speciella åtgärder. Huruvida olika avdelningar ska blandas vid kurstillfället visade sig vara en fråga ifall olika subkulturer inom företaget kan blandas. I det här fallet tyckte informanterna det var fördelaktigt för företaget att blanda subkulturer som förhinder mot att de växer ifrån varandra i olika riktningar. Slutsatsen visar att om målet för en kurs inom kompetensutveckling på ett multinationellt företag är att sprida information till och mellan deltagarna så är de viktigaste aspekt

Many models for nucleating and growing precipitates have been developed. Each model with their own advantages and disadvantages. Only few of those models are made for heterogeneous nucleation (on dislocations) and most of them are based on the mean radius approach. In the literature study by Vonk (2016) one of these models (by Zurob et al. (2002)) was explained, analysed and tested for different values of the model parameters and different initial values. The model showed to be flexible, but still had some drawbacks, of which the mean radius aspect was the most limiting. A new distribution model is developed in this master thesis, based on the KWN model by Robson (2014) and Den Ouden et al. (2013). Even though the approach has changed, the nucleation and growth rate were adopted from the model by Zurob et al. (2002), which still included some drawbacks. Some of these drawbacks are eliminated by extending the model and some are recommended for future work. The two main drawbacks that were eliminated, were the lack of influence of all elements in the system and the competition between nucleation sites and different precipitate compositions. All elements in the system influence the nucleation and growth of the precipitates, even when the elements do not participate in the precipitate. A multi-component model is the extension to capture this complexity (Den Ouden et al. (2013)). Because most steel alloys contain many alloying elements, different precipitates can occur simultaneously (for instance, Nb(C,N), AlN and MnS) and complex precipitates may exist, like (Nb,Ti)(C,N). Also precipitates may nucleate at various nucleation sites. A multi-precipitate model is the extension to capture this complexity. The results of the simulations using the distribution model and its extensions are analysed and compared, showing the flexibility of the model. The implementation includes the multi-component and multi-precipitate extension, but no model for complex precipitates yet., Electrical Engineering, Mathematics and Computer Science, Delft Institute of Applied Mathematics, Numerical Analysis

We study the heterogeneous wireless sensor networks (WSNs) and propose the necessary condition of the optimal sensor deployment. Similar to that in homogeneous WSNs, the necessary condition implies that every sensor node location should coincide with the centroid of its own optimal sensing region. Moreover, we discuss the dynamic sensor deployment in both the homogeneous and the heterogeneous WSNs with limited communication range for the sensor nodes. The purpose of sensor deployment is to improve sensing performance, reflected by distortion and coverage. We model the sensor deployment problem as a source coding problem with distortion reflecting sensing accuracy. However, when the communication range is limited, a WSN is divided into several disconnected sub-graphs under certain conditions as we will discuss in this paper. In such a scenario, neither the conventional distortion nor the coverage represents the sensing performance as the collected data in disconnected sub-graphs cannot be communicated with the access point. By defining an appropriate sensing performance measure, we propose a Restrained Lloyd (RL) algorithm and a deterministic annealing (DA) algorithm to optimize sensor deployment in both the homogeneous and heterogeneous WSNs. Our simulation results show that both the DA and the RL algorithms outperform the existing algorithms when communication range is limited.

Group composition is common in education and is fairly well examined at a school level but not within competence development in a working environment. How should a group of coworkers be grouped when attending a course? This can be a complicated question, especially at a big company such as Atlas Copco which has employees from all over the world. The main object with this report is to find which aspects has to be taken into account when putting people together in groups at a multinational company and secondly give a proposal to Atlas Copco for how the groups should be constructed in the company. The data collected for this report was gathered mostly during the two focus group discussions that were held by the researchers. This material was complemented with interviews held before and after the focus groups meetings, to get a more profound picture of the company. The outcome of the interviews and discussions were then compared with relevant literature on the subject, to be able to make an analysis on the important factors. Findings from the analysis shows that language and previous knowledge are limiting factors and should therefore determine if a person is allowed to attend a certain course. The more knowledge the course participants have in the subject and how well the participants understand the spoken language, the more information exchange will occur between the teacher and course participants. Geographical cultural differences were found to have a slight importance when designing groups but not so significant that special action has to be taken. Combining or keeping separate departments apart during a course were found to be a question on whether or not the different subcultures at the company could be mixed or not. In this case the informants in the research believed it was more beneficial for the company to mix, to prevent the subcultures to grow in separate ways. The conclusion is that the most important aspect of a group constellation are the language and pr, Gruppsammansättningens betydelse är en omdiskuterad företeelse som är vanligt förekommande i utbildningssammanhang och är relativt väl utforskat på skolnivå men inte när det gäller kompetensutveckling inom arbetslivet. Hur ska en gruppsammansättning av arbetskamrater se ut vid ett kurstillfälle? Det kan vara en komplicerad fråga, speciellt på ett stort företag som Atlas Copco vilka har anställda över hela världen. Huvudsyftet med denna rapport är att finna vilka aspekter som behöver tas hänsyn till när folk blir sammansatta i grupper i multinationella företag och ge förslag till Atlas Copco hur grupperingen ska genomföras inom företaget. Data för denna rapport insamlades mestadels under två fokusgruppsdiskussioner som hölls av forskarna. Som komplement till detta material hölls intervjuer både före och efter fokusgruppsmötena för att få en bredare inblick i företaget. Resultatet från intervjuerna och diskussionerna jämfördes sedan med relevant litteratur för att analysera de viktiga faktorerna. Resultat av analysen visar att språkkunskaper och tidigare kunskap i ämnet behöver vara begränsande faktorer vid bestämmandet om en person tillåts närvara vid specifika kurser. Om en person inte har tillräcklig kunskap i språket kursen hålls i, sker inget lyckat informationsutbyte mellan lärare och kursdeltagare och samma gäller aspekten med tidigare kunskap. Geografiskt kulturella skillnader visades vara av ringa betydelse vid designande av grupper men inte så viktiga att det behövs vidtas speciella åtgärder. Huruvida olika avdelningar ska blandas vid kurstillfället visade sig vara en fråga ifall olika subkulturer inom företaget kan blandas. I det här fallet tyckte informanterna det var fördelaktigt för företaget att blanda subkulturer som förhinder mot att de växer ifrån varandra i olika riktningar. Slutsatsen visar att om målet för en kurs inom kompetensutveckling på ett multinationellt företag är att sprida information till och mellan deltagarna så är de viktigaste aspekt

Many models for nucleating and growing precipitates have been developed. Each model with their own advantages and disadvantages. Only few of those models are made for heterogeneous nucleation (on dislocations) and most of them are based on the mean radius approach. In the literature study by Vonk (2016) one of these models (by Zurob et al. (2002)) was explained, analysed and tested for different values of the model parameters and different initial values. The model showed to be flexible, but still had some drawbacks, of which the mean radius aspect was the most limiting. A new distribution model is developed in this master thesis, based on the KWN model by Robson (2014) and Den Ouden et al. (2013). Even though the approach has changed, the nucleation and growth rate were adopted from the model by Zurob et al. (2002), which still included some drawbacks. Some of these drawbacks are eliminated by extending the model and some are recommended for future work. The two main drawbacks that were eliminated, were the lack of influence of all elements in the system and the competition between nucleation sites and different precipitate compositions. All elements in the system influence the nucleation and growth of the precipitates, even when the elements do not participate in the precipitate. A multi-component model is the extension to capture this complexity (Den Ouden et al. (2013)). Because most steel alloys contain many alloying elements, different precipitates can occur simultaneously (for instance, Nb(C,N), AlN and MnS) and complex precipitates may exist, like (Nb,Ti)(C,N). Also precipitates may nucleate at various nucleation sites. A multi-precipitate model is the extension to capture this complexity. The results of the simulations using the distribution model and its extensions are analysed and compared, showing the flexibility of the model. The implementation includes the multi-component and multi-precipitate extension, but no model for complex precipitates yet., Electrical Engineering, Mathematics and Computer Science, Delft Institute of Applied Mathematics, Numerical Analysis

The purpose of this paper is to examine if there are any differences or similarities when it comes to teaching religion in a multicultural school versus teaching religion in a homogeneous school in Sweden. How do teachers describe religious education in schools and how do they justify their teaching strategies? What similarities or differences are there between teachers' approaches when teaching religion in homogeneous versus multicultural schools?The study is based on qualitative interviews which includes a total of four schools; two homogeneous and two multicultural. These schools have been selected with the help of the Migration Board's annual report from 2014 as well as from my own personal knowledge. One religious teacher from each of the schools was interviewed.The conclusion, among others, is that ethnic Swedish pupils do not have the same understanding of religion as students of different ethnicity. It also proved that by having students with a different culture to the Swedish talk about their traditions and religion developed a greater understanding among all students., Syftet med detta examensarbete har varit att undersöka huruvida det är några skillnader eller likheter med att undervisa om religioner på en mångkulturell respektive homogen skola i Sverige. Hur beskriver lärarna undervisningen om religioner i skolan och hur motiverar de sina undervisningsstrategier? Vilka likheter eller skillnader finns mellan lärarnas syn på undervisning om religioner i homogena respektive mångkulturella skolor?Undersökningen baseras på kvalitativa intervjuer där sammanlagt fyra skolor är med i studien, två homogena samt två mångkulturella. Dessa skolor har valts ut med hjälp av Migrationsverkets årsrapport från 2014 samt personlig kännedom. En religionslärare från vardera skola har intervjuats.Slutsatserna blev bland annat att de etniskt svenska eleverna inte hade en förståelse för religion på samma sätt som eleverna med annan etnicitet. Det visade sig också att en större förståelse utvecklades bland alla elever genom att låta elever med annan kultur än den svenska berätta om sina traditioner och religion.

Reservoir simulation is a key tool to get insight in complex fluid flow phenomena occurring in many petroleum reservoirs, creating the possibility to quantify fluid productions and their uncertainty regarding many unknown properties. It has been shown by experimental and theoretical research that under certain criteria immiscible (multiphase) and miscible (single-phase) displacements can develop instabilities. These instabilities cause the displacing fluid to finger though the displaced oil, which is referred to as viscous fingering. Moreover, reservoir rock heterogeneity has shown to be capable to amply these phenomena. However, to limit computational costs, reservoir simulations typically use far lower grid resolution than the scale at which incomplete mixing phenomena occur. Numerical truncation errors imposed by large grid blocks will conceal small scale physical phenomena that contribute to unstable displacements. These sub-grid flow features are what is called incomplete mixing, as opposed to the fully mixed scenario inherent to the use of low resolution grids. To cope with this problem, effective models have been developed that make use of effective fluid properties in order to capture the sub-grid effect of incomplete mixing. Todd and Longstaff’s model is the most widely utilized model in the petroleum industry. Like similar models, one major disadvantage is that this effective model depends on an undefined scalar mixing parameter, which must be obtained from either high resolution simulation or experimental data. Dynamic local grid refinement (DLGR) is a simulation technique that can adapt the spatial grid resolution to the scale at which the physical phenomena occur without refining the grid over the entire domain. This can be achieved by means of local refinement and coarsening of the computational grid dynamically at every time step where small scale, local phenomena occur using predefined error criteria. This way DLGR could provide the means to solve fo, Petroleum Engineering, Geoscience & Engineering, Civil Engineering and Geosciences

The purpose of this paper is to examine if there are any differences or similarities when it comes to teaching religion in a multicultural school versus teaching religion in a homogeneous school in Sweden. How do teachers describe religious education in schools and how do they justify their teaching strategies? What similarities or differences are there between teachers' approaches when teaching religion in homogeneous versus multicultural schools?The study is based on qualitative interviews which includes a total of four schools; two homogeneous and two multicultural. These schools have been selected with the help of the Migration Board's annual report from 2014 as well as from my own personal knowledge. One religious teacher from each of the schools was interviewed.The conclusion, among others, is that ethnic Swedish pupils do not have the same understanding of religion as students of different ethnicity. It also proved that by having students with a different culture to the Swedish talk about their traditions and religion developed a greater understanding among all students., Syftet med detta examensarbete har varit att undersöka huruvida det är några skillnader eller likheter med att undervisa om religioner på en mångkulturell respektive homogen skola i Sverige. Hur beskriver lärarna undervisningen om religioner i skolan och hur motiverar de sina undervisningsstrategier? Vilka likheter eller skillnader finns mellan lärarnas syn på undervisning om religioner i homogena respektive mångkulturella skolor?Undersökningen baseras på kvalitativa intervjuer där sammanlagt fyra skolor är med i studien, två homogena samt två mångkulturella. Dessa skolor har valts ut med hjälp av Migrationsverkets årsrapport från 2014 samt personlig kännedom. En religionslärare från vardera skola har intervjuats.Slutsatserna blev bland annat att de etniskt svenska eleverna inte hade en förståelse för religion på samma sätt som eleverna med annan etnicitet. Det visade sig också att en större förståelse utvecklades bland alla elever genom att låta elever med annan kultur än den svenska berätta om sina traditioner och religion.

El objeto de la presente investigación, trata de poner de manifiesto cómo el diseño urbano de los barrios entre los años 60 a 70, han descrito procesos constructivos análogos, sin tener en cuenta las condiciones locales del territorio en el que se estaban construyendo. La expansión del sector de la construcción desde mediados del siglo XX hasta principios del siglo XXI trajo consigo la construcción a un ritmo vertiginoso, especialmente en la década de los 60 a los años 70, por los acontecimientos históricos y demográficos ocurridos en España. Este acelerado desarrollo, llevó a la realización de multitud de periferias y nuevos barrios, que en muchos de los casos presentan características y parámetros similares, sin responder en gran parte de los casos a las condiciones de contorno del territorio en el que se ubicaban., The purpose of this research is to show how urban design of neighborhoods between 60-70, have described similar construction processes, regardless of local conditions of the territory in which they were built. The expansion of the construction sector since the mid-twentieth century to the early twenty-first century brought the construction at a rapid pace, especially in the 60s to the 70s, for historical and demographic developments in Spain. Thisaceleratedgrowth, led to the realization of many suburbs and new neighborhoods, which in many cases have similar characteristics and parameters, largely unanswered cases the boundary conditions of the territory in which were located.

CeO_2-ZrO_2 composite nanoparticles with mesoporous and spherical morphologies were assembled into different homogeneously dispersed, domain, and core-shell structures by changing the reaction conditions, such as the heating rate, acid, and solvent, in supercritical alcohols. Ce_xZr_<1−x>O_2 with homogeneous structures were prepared from Ce(NO_3)_3 and ZrO(NO_3)_2 in the presence of formic acid in methanol by rapid heating (500℃/min) to 300℃, while CeO_2–ZrO_2 with domain structures were obtained by slow heating (5.4℃/min). Treatment of mesoporous and spherical ZrO_2 nanoparticles with a Ce(NO_3)_3 solution in supercritical conditions yielded CeO_2-ZrO_2 nanocomposites with core-shell morphologies, while solvents playing a key role in controlling the thickness of the outer shell; methanol produced a very thin outer shell (<1 nm) of cubic CeO_2 and 2-propanol afforded a thick outer shell (100-200 nm) of cubic CeO_2., journal article

Reservoir simulation is a key tool to get insight in complex fluid flow phenomena occurring in many petroleum reservoirs, creating the possibility to quantify fluid productions and their uncertainty regarding many unknown properties. It has been shown by experimental and theoretical research that under certain criteria immiscible (multiphase) and miscible (single-phase) displacements can develop instabilities. These instabilities cause the displacing fluid to finger though the displaced oil, which is referred to as viscous fingering. Moreover, reservoir rock heterogeneity has shown to be capable to amply these phenomena. However, to limit computational costs, reservoir simulations typically use far lower grid resolution than the scale at which incomplete mixing phenomena occur. Numerical truncation errors imposed by large grid blocks will conceal small scale physical phenomena that contribute to unstable displacements. These sub-grid flow features are what is called incomplete mixing, as opposed to the fully mixed scenario inherent to the use of low resolution grids. To cope with this problem, effective models have been developed that make use of effective fluid properties in order to capture the sub-grid effect of incomplete mixing. Todd and Longstaff’s model is the most widely utilized model in the petroleum industry. Like similar models, one major disadvantage is that this effective model depends on an undefined scalar mixing parameter, which must be obtained from either high resolution simulation or experimental data. Dynamic local grid refinement (DLGR) is a simulation technique that can adapt the spatial grid resolution to the scale at which the physical phenomena occur without refining the grid over the entire domain. This can be achieved by means of local refinement and coarsening of the computational grid dynamically at every time step where small scale, local phenomena occur using predefined error criteria. This way DLGR could provide the means to solve fo, Petroleum Engineering, Geoscience & Engineering, Civil Engineering and Geosciences

High performance MgB2 bulks using carbon-coated amorphous boron as a boron precursor were fabricated by Cu-activated sintering at low temperature (600 °C, below the Mg melting point). Dense nano-MgB2 grains with a high level of homogeneous carbon doping were formed in these MgB2 samples. This type of microstructure can provide a stronger flux pinning force, together with depressed volatility and oxidation of Mg owing to the low-temperature Cu-activated sintering, leading to a significant improvement of critical current density (Jc) in the as-prepared samples. In particular, the value of Jc for the carbon-coated (Mg1.1B2)Cu0.05 sample prepared here is even above 1 x 105 A cm−2 at 20 K, 2 T. The results herein suggest that the combination of low-temperature Cu-activated sintering and employment of carbon-coated amorphous boron as a precursor could be a promising technique for the industrial production of practical MgB2 bulks or wires with excellent Jc, as the carbon-coated amorphous boron powder can be produced commercially at low cost, while the addition of Cu is very convenient and inexpensive.

High performance MgB2 bulks using carbon-coated amorphous boron as a boron precursor were fabricated by Cu-activated sintering at low temperature (600 °C, below the Mg melting point). Dense nano-MgB2 grains with a high level of homogeneous carbon doping were formed in these MgB2 samples. This type of microstructure can provide a stronger flux pinning force, together with depressed volatility and oxidation of Mg owing to the low-temperature Cu-activated sintering, leading to a significant improvement of critical current density (Jc) in the as-prepared samples. In particular, the value of Jc for the carbon-coated (Mg1.1B2)Cu0.05 sample prepared here is even above 1 x 105 A cm−2 at 20 K, 2 T. The results herein suggest that the combination of low-temperature Cu-activated sintering and employment of carbon-coated amorphous boron as a precursor could be a promising technique for the industrial production of practical MgB2 bulks or wires with excellent Jc, as the carbon-coated amorphous boron powder can be produced commercially at low cost, while the addition of Cu is very convenient and inexpensive.

High performance MgB2 bulks using carbon-coated amorphous boron as a boron precursor were fabricated by Cu-activated sintering at low temperature (600 °C, below the Mg melting point). Dense nano-MgB2 grains with a high level of homogeneous carbon doping were formed in these MgB2 samples. This type of microstructure can provide a stronger flux pinning force, together with depressed volatility and oxidation of Mg owing to the low-temperature Cu-activated sintering, leading to a significant improvement of critical current density (Jc) in the as-prepared samples. In particular, the value of Jc for the carbon-coated (Mg1.1B2)Cu0.05 sample prepared here is even above 1 x 105 A cm−2 at 20 K, 2 T. The results herein suggest that the combination of low-temperature Cu-activated sintering and employment of carbon-coated amorphous boron as a precursor could be a promising technique for the industrial production of practical MgB2 bulks or wires with excellent Jc, as the carbon-coated amorphous boron powder can be produced commercially at low cost, while the addition of Cu is very convenient and inexpensive.

Investigation on Crosstalk in Multi-core Optical Fibers, We start by describing what SDM is, the problem at hand for it’s been considered and the different solutions it can provide. We focus on Multi - Core Fibers (MCF) as the favorite solution re garding SDM and proceed to study the main parameter that dictates the performance and limitations of said fiber, the crosstalk. We explain the different methods for accurately estimate the crosstalk under different situations depending on the nature of the cores and if they are using trench or not. We demonstrate the different approaches with our own simulations as well as the bend insensitiveness of heterogeneous MCF. We finish this work by establishing different strategies to obtain the lowest possible c rosstalk and proceed to propose a design of our own , a 19 core Heterogeneous Trench Assisted MCF that is made by 3 types of cores and then proceed to show the results of the simulations carried to this design.