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The aim of this work is to develop the electrical and software part of a newly designed automated system for sowing, watering and chemical treatment, which allows to integrate and automate the processes of sowing, watering and chemical treatment in greenhouse farms. It is necessary to develop a control system for the newly designed automated system for sowing, watering and chemical treatment. PLC and CNC software "Mach3mill" will be used to realize the goal. It is necessary to determine the characteristics of the developed control system and to define M commands ensuring the automatic control of the system. It is also necessary to describe the operating modes of the developed control system and to create sample control programs for operating the system in different modes. The newly designed automated system will have the ability to work with various seeds, fertilizers and chemicals; change the quantities of items supplied; changing the locations of the delivery points of the items; modular structure, allowing it to be configured according to the needs of each client; changing the working area of the system considering the specific task. [ABSTRACT FROM AUTHOR]

Modular Construction has been considered as an effective alternative to conventional high-rise buildings. It has gained an increasing attention amount of attention over the last few decades as a way to advance sustainable construction. Besides the many benefits of modular construction technology in high-rise building construction when compared to conventional methods, the application of a modular system requires the interaction of various activities. The modular system will change the relationship between activities that were originally independent of each other (conventional methods) to become interdependent, and the potential risk will certainly occur especially in high-rise buildings. Therefore, it is necessary to do research on risk management of modular construction in high-rise building. This research is focused on high rise residential building. This study aims to analyze the factors that influence risk manageability in high-rise residential building modular construction on cost and time performance and to build risk manageability modeling using System dynamics on high-rise residential building modular construction projects. Sixteen indicators were extracted from the literature review and specialist interviews to conduct a sustainability evaluation. A survey was submitted to case project developers, designers, supervisors, manufacturers and contractors in Indonesia. The tentative hypothesis is that risk manageability modeling using system dynamics in modular construction projects high-risk residential building can improving time performance. finally, policy recommendations for improvement are needed. [ABSTRACT FROM AUTHOR]

Research and development toward flux switching machines (FSMs) have increased throughout the past decades. It comes handy with the advantage of having high output torque and power densities which suitable in electric vehicle application. Most research have been focusing only on inner rotor configuration leaving a few outer rotor research. As to achieve high output torque at low speed and less copper loss thus resulting to the development of outer rotor permanent magnet flux excitation machine PMFSM. Despite having such advantages, the design faces such disadvantage of having high cogging torque and non-sinusoidal back-emf waveform. In order to overcome the highlighted problems, this paper presents initial analyses on modular outer rotor structure for hybrid excitation flux switching motor based on finite element method. From the analyses, it shows that the modular rotor structure has good capability in reducing cogging torque and back-emf waveforms. [ABSTRACT FROM AUTHOR]

The paper deals with the issues of increasing the efficiency of functioning of synergetic robotic systems by searching for waysto improve the simulationmodels underlying them (increasing the degree of completeness and adequacy). The architecture of a hybrid simulation model is proposed on the example of a basic complex modeа of functioningания of a collaborative process. The model is built according to the modular principle and combines discrete-event modules and real-time modules (dynamic modeling, etc.). The platform solution gives the model maximum flexibility when it is specialized for a specific technological process. The functionality of the model is aimed not only at modeling regular situations, but also allows you to forecast the impact of disturbing factors on the development of the situation and the quality of the joint production process of the operator and robot. The interface of the model allows you to include the operator in the planning process of tactical decisions, due to the possibility of organizing control actions on it by means of the effector system. [ABSTRACT FROM AUTHOR]

The living standard of a society is often evaluated on the basis of the quality and availability of housing. In housing policy, the role of the state is to ensure stability in the market environment that will allow households to live according to their income as well as to support labor mobility by using an existing housing stock without erratic excessive pressure on housing construction. Almost 95% of flats in Slovakia are in personal ownership of owner-occupants. In terms of the labor mobility and the flexibility of the labor market, the owner-occupied housing is rather detrimental. The solution to this fact can be supported by the construction of new rental housing, not only by the state, but also by the private sector. Although there are various state concepts for the construction of rental housing, so far it is all just in paper form and nothing is happening in reality. There is also some talk about implementation of modular buildings in construction of rental housing. The aim of the research is to evaluate the potential for the construction of modular apartment buildings in Slovakia. This is one of the reactions to the ongoing policy of the state, where the government of the republic committed to the massive construction of rental housing in its government program statement for 2021 - 2024. The main research question is whether there are enough companies in Slovakia that will be able to realize the number of modular apartment buildings, which the state says about in its program statement. The off-site modular construction has several advantages over traditional onsite construction. However, some disadvantages or barriers to the adoption of the modular construction generally or in Slovakia are also mentioned in the study presented. As to potential construction of apartment buildings, comparison of modular and traditional construction methods, from construction cost and construction time point of view was performed. The construction companies and especially modular construction companies from the Slovak construction market were engaged in the comparison. The companies provided the data related to examined economic and technological parameters (cost and time) of construction. More or less expected results of the comparative study are presented in the contribution. Based on the results of the presented study, it can be stated that the potential for modular housing construction in Slovakia exists. [ABSTRACT FROM AUTHOR]

Sustainable development based on economic, social and technological points of view is especially relevant in the construction industry. In different countries there are environmental standards for assessing objects. In Russia, this standard is called Green Zoom. The article considers the issue of applying sustainable architecture technologies that can be used in the construction of campuses. The technologies used in the design of the building and infrastructure are highlighted. As building technologies, the modular layout of the building, the use of green roofing are given. [ABSTRACT FROM AUTHOR]

Building information modeling (BIM) and modular construction are important modern technologies for the sustainability of the construction industry. However, both directions today have practical and theoretical defects that prevent the spread of each approach separately and in combination, thereby opening up space for research and new developments. Therefore, it is advisable to study this complex of design and construction technologies in order to increase efficiency. The purpose of this study is to obtain theoretical data for the integration of information modeling technologies in modular construction and further search for new ways of developing these areas. To achieve this goal, it is necessary to solve a number of tasks to analyze the features of the main tasks and design processes of modular design, the features and capabilities of the information modeling functionality, and also to perform an expert assessment. This article proposes a selection of the most promising and effective tasks of modular and BIM functions among the general lists of items obtained on the basis of literature analysis. The selection is carried out on the basis of the application index, which is formed on the basis of expert assessments. As a result, two groups of the most promising tasks of modular construction and the most effective information modeling functions were obtained. The results of the study are applicable for drawing up the theoretical basis and methodological basis for information modeling of modular objects, as well as for further research in the field of modular construction. [ABSTRACT FROM AUTHOR]

The article substantiates the relevance and expediency of the modular design method using in the development of multi-details sewing products with unified cut details. In the modern world of fashion there is a clear trend in the production of modular multi-details clothes, but the methods of its pattern design have not yet been studied enough. For the implementation of modular clothes in mass production it is necessary to develop methods of its industrial design, as well as formalize the process of design-projects developing using new materials and technologies. Clothes with modular construction may be widely used, are in demand, because they meet the modern requirements of the consumers, namely, allow individualizing of human appearance. In the article there is a description of modular multi-details clothes design method which is intended for implementation of innovative materials and new manufacturing technologies in apparels production. The reported study was funded by RFBR, project number No. 19-312-90048. [ABSTRACT FROM AUTHOR]

Steel trihedral trusses are used as flat roofs of public and industrial buildings and structures. A modular system can be used to transport the structures of trihedral trusses. The paper presents the results of numerical studies of modular trihedral trusses for flat roofs of buildings with transversal partitioning into dispatch modules. Application of modular system for trihedral trusses is aimed at mass production with widespread delivery by various cargo transport. Numerical studies based on the computational mathematical model of a space-core truss allows to estimate deformability of a trihedral truss with pliable mounting junctions of adjacent modules for various forms of loading. We describe peculiarities of constructing variative computational models which take into account the peculiarities of structures with noncentered connection junctions of struts from single corners to the chords of a composite profile made of channel's and corner's rolled elements. The most stressed elements of the spatial and strut system of trihedral trusses with butt joint adjacency of struts to chords are determined. Results are presented in a table for comparative analysis of deformability for various calculation models. According to the comparative analysis of deformability of mathematical calculation models for trihedral roof trusses, the use of pliable mounting junctions of module coupling has been substantiated. [ABSTRACT FROM AUTHOR]

In this paper, we discuss some properties of generalized modular metric spaces. This space was first introduced by Turkoglu and Manav in 2018. Later, we extend the concepts about contraction mappings in generalized modular metric spaces. We also develop a convexity structure and defined the N normal structure in this space.The results show us that if X is a complete modular metric space and TN is a contraction mapping then T has a unique fixed point.Moreover, we need the constant of generalized modular metric axiom should be less than or equal to 1 to guarantee the ball is closed. The closeness property of the ball is necessary to generate normal structure in generalized modular metric space. This normal structure property assures the existence of the fixed point of a nonexpansive mapping. [ABSTRACT FROM AUTHOR]

A technique based on a neural network was developed, which has shown a high efficiency of searching for the best structure of meta-atoms for modular design of acoustic metamaterials on the model system. A neural network with a three-layer structure required less than 1% of computational time in comparison with a direct numerical analysis of all possible variants of metamaterials in order to find a metamaterial with the required acoustic properties. The calculations were carried out using finite element method and CAE Fidesys software. [ABSTRACT FROM AUTHOR]

A high voltage steps up converter suitable for renewable energy application has been presented here. The roposed converter has been derived from the basic SEPIC converter with two voltage multiplier cells (VMC) to produce high voltage transformation ratio. Operating principles are discussed thoroughly. The structure becomes modular as a pair of coupled inductor support for high conversion ratio reducing requirement with additional components. To verify the effectiveness of converter simulations are carried out with an input fed with 18V to produce 272V to deliver an output power of 140W. The switch stress and diode stress contributes to 36% of output voltage. [ABSTRACT FROM AUTHOR]

Prefabricated Pre-finished Volumetric Construction (PPVC) is the advanced modular construction technology introduced by Singapore Building and Construction Authority (BCA) to promote a modern practice in construction sector which rectifying the fragmentation of construction industries towards higher productivity and more efficiency in project delivery. PPVC is an innovative approach to replace the traditional on-site construction method which construct a building using modular units away from the physical site but into a controlled factory environment. The adoption of PPVC has a significant solution to tackle the current level of quality, workmanship, productivity, non-environment construction, lacking on-site safety awareness, construction wastage and excessive reliance on unskilled foreign labors associated with conventional construction methods. In Malaysian, PPVC still lagging far behind in the development of Malaysian construction industry. The effectiveness of using PPVC can reduce the number of on-site contractors, increase the efficiencies in the use of resource and minimize the construction waste. This study is to investigate the factors affecting the adaptation of PPVC in Malaysia Construction Industry and recommend a mitigation to increase the possibility of using PPVC in future development of Malaysian industry. There is significant risk on using PPVC as the reliability is much harder to guarantee than conventional construction method. PPVC can be beneficial, but only if everyone involved has the proper experience and ability to perform such activities. This study contributes to industry practitioners to enhance their understanding of PPVC to increase the affordability and sustainability of houses in the future development of Malaysian industry. [ABSTRACT FROM AUTHOR]

Particle tracking is a fundamental part of the event analysis in high energy and nuclear physics (HENP). Events multiplicity increases each year along with the drastic growth of the experimental data which modern HENP detectors produce, so the classical tracking algorithms such as the well-known Kalman filter cannot satisfy speed and scaling requirements. At the same time, breakthroughs in the study of deep learning open an opportunity for the application of high-performance deep neural networks for solving tracking problems in a dense environment of experiments with heavy ions. However, there are no well-documented software libraries for deep learning track reconstruction yet. We introduce Ariadne, the first open-source library for particle tracking based on the PyTorch deep learning framework. The goal of our library is to provide a simple interface that allows one to prepare train and test datasets and to train and evaluate one of the deep tracking models implemented in the library on the data from your specific experiment. The user experience is greatly facilitated because of the system of gin-configurations. The modular structure of the library and abstract classes let the user develop his data processing pipeline and deep tracking model easily. The proposed library is open-source to facilitate academic research in the field of particle tracking based on deep learning. [ABSTRACT FROM AUTHOR]

Complex fracture facial trauma is a condition when some part of the skull shattered into multiple pieces. Intricate fractured skull often deforms the suspect's face, which damaging the aesthetic and the functionality of some part of the skull, or even the whole skull. The procedure to fix this condition uses mini plates in large parts of the procedure. Unfortunately, there is some condition when the existing mini plates can not handle the condition due to the fracture position and another obstacle like teeth root. The lack of mini plates that can adapt according to the obstacles makes the fixation is difficult. This study aims to develop modular mini plates that can adapt the fracture lines and the obstacles that exist in the patients. The method of this study is assembling the modular mini plates to determine the possible angle configuration using CAD software and determining the maximum load of each angle configuration using finite element analysis simulation software. The CAD software result concludes that the possible angle configuration using modular mini plates with 18 holes and pins varies from 40° to 320° with 20° interval (15 configurations). 0°, 20°, and 340° deemed not suitable because the model will collide with each other if using the angle as mentioned earlier configuration. The Von- Mises Stress of each configuration varies, with the maximum value is 535,03 MPa in 240° configuration and the minimum value is 461,26 MPa in 320° configuration with 10 N load configuration. This study concludes that the modular concept is applicable in some angle configuration. [ABSTRACT FROM AUTHOR]

Low levelized cost of electricity (LCOE), higher revenues and lower expenditures are in the focus of all commercial CSP projects. In order to reach high performance in parabolic trough solar fields, the key components have to be of high quality and durability. The precision exigencies on the shape of the reflector surface in the order of tens of milliradians and the relative position of the absorber tube of concentrating collectors in the order of millimeters are unusually strict for constructions of this size, that typically exceed 70 square meters per module. To ensure high optical, mechanical and thermal performance of a complete solar field, specific quality assurance measures must be performed throughout the construction of a power plant, including early phases of the project such as the selection of adequate key components. Quality control measurements in the assembly line and spot check measurements in the solar field shall ensure accurate assembly and correct installation of the collectors [1]. For the enhanced verification of the solar field quality for final acceptance, comprehensive measurements with a large empirical basis taken from unmanned aerial vehicles [2] are recommended, before or while the thermal performance of the solar field is tested. This combined strategy is called hybrid testing. The paper gives an overview about quality management measures that finally lead to a high-quality solar field, lowering risks of failures, reducing ramp-up time and therewith contributing to lowering LCOE of parabolic trough power plants. A techno-economic evaluation shows that well-conceived quality control of solar field components leads to a higher overall plant performance, which results in additional revenues that pay back the additional efforts within a short time. [ABSTRACT FROM AUTHOR]

Solar Thermal Electricity (STE/CSP) Tower Plants with single towers are limited in size as the heliostat field efficiency decreases significatively when the plant becomes larger. As plant size is an important driver in reducing the generation costs of STE plants - due to the relative high impact of the power block - this fact represents a great disadvantage for tower plants as compared with parabolic through ones, which might have unlimited size of the mirror field thanks to the modular loop concept. This effect is much stronger in locations with high atmospheric attenuation factor. This paper points out the optical and conceptual advantages of designing the future solar tower plants with a modular approach. Until now, the only approach was to optimize the field layout and the tower height of single units. Keeping the same central storage system and power block improvements in plant efficiency close to 25% can be achieved by splitting the single surrounding heliostat field into several polar field units. But perhaps the most important impacts in the necessary reduction of cost could be twofold: first, finding out a kind of standard module – perhaps between 30 – 50 MW – which can make designs easier and standardize important components like receivers and heliostats to produce their main parts in large series and second, being able to build STE tower plants in the 500 MW range with single power block units. This would provide a wide range of advantages and can position solar tower technology as a competitive concept for plants of unlimited size, boosting the deployment of STE/CSP tower plants in a standard, modular and cost-efficient way. [ABSTRACT FROM AUTHOR]

The MOSAIC project aims to develop a commercial CSP plant concept over 1GW nominal capacity. High nominal capacity is reached in a modular way, where each MOSAIC module delivers thermal energy to connected thermal energy storage systems that supply their energy to a high capacity power block (>1GW). This modular configuration significantly reduces the specific cost of the power block (€/MW installed). Each MOSAIC module consists of an innovative fixed spherical mirror concentrator arranged in the form of a semi-Fresnel and a moving receiver driven by a low-cost cable tracking system. This configuration reduces the amount of moving parts of the entire system, lowering the cost of the solar field and keeping high concentration ratios. This will ensure high working temperatures and therefore high cycle efficiencies and cost-effective use of thermal storage systems. Energy from the sun is collected, concentrated and transferred to the heat transfer fluid at module level, where, due to the modular concept, the distances from the solar concentrator to the receiver are much shorter than in typical solar tower technologies. As a result, energy collection efficiency is maximized, atmospheric attenuation is minimized, and precision requirements can be lowered. All these technical benefits can contribute to a lower capital cost of the whole system, while ensuring efficiency and reliability. This therefore has a strong impact on the final cost of electricity production. [ABSTRACT FROM AUTHOR]

The mechanical properties of thin-walled plastic components are limited. One approach to improve the strength or stiffness of these components is to reinforce the thin-walled areas with an individually adapted Fused Deposition Modeling structure. Fused Deposition Modeling (FDM) is one of the most commonly used additive manufacturing processes. This process is characterized by the deposition of a fused, thermoplastic filament. Depending on the form of the reinforcement structure, the resulting hybrid structure should show higher strength or stiffness. The objective of the project is to determine constructive design and process guidelines for FDM structures. The FDM structure is to be used as a partial reinforcement for lightweight components and be adapted to the respective load conditions. Because of the lightweight application, the FDM structure should also have the lowest possible weight. The optimization of the FDM parts for different load cases is realized by adapting the design parameters. These parameters influence the layer generation and therefore also the inner structure of the FDM parts. In preliminary studies, the manufacturing restrictions of the FDM process are defined. The specimens are manufactured based on the Design of Experiments. To determine the static strength properties, different tests (tensile, compression, flexural, torsion and impact) are carried out. The investigations show that the filling strategy affects the mechanical properties. As a result of the investigations, design and process guidelines for the FDM structures are established according to the load conditions. [ABSTRACT FROM AUTHOR]

Masonry structures with fictile tubules were a distinctive building technique of the Mediterranean area. This technique dates back to Roman and early Christian times, used to build vaulted constructions and domes with various geometrical forms by virtue of their modular structure. In the present work, experimental tests were carried out to identify the mechanical properties of hollow clay fictile tubules and a possible reinforcing technique for existing buildings employing such elements. The experimental results were then validated by devising and analyzing numerical models with the FE software Abaqus, also aimed at investigating the structural behavior of an arch via linear and nonlinear static analyses. [ABSTRACT FROM AUTHOR]

Nowadays, the lack of adequate housing in Cape Verde is a growing problem. The migration of the population living in the countryside to the major cities generates an increase of the diameter of the cities. With the lack of economic power, the migrating families tend to occupy the land with houses which don't present proper conditions to living. Praia is the capital of Cape Verde and so on the biggest city of the country. This fact leads Praia to being the city with major economic power and job offer in all country. Consequently, Praia has developed the biggest slum of the Cape Verde and it is urgent to approach this problem in order to create solutions that reveal capacity to start solving it. Cape Verde's unique dry subtropical climate turns indispensable a careful resolution of the housing, in order to ensure the comfort of the occupants. The modular construction is a solution with potential to approach this problem with a fast and economic response. In order to answer the situation, this article introduces a modular solution in order to reach the needing of thermal comfort to the specific case of Praia. [ABSTRACT FROM AUTHOR]

A stakeholder needs assessment, carried out under the EU-EURAC and EU-ENEN II projects, clearly showed that, at the European level, there are a significant and constant need for post-graduates with skills in radiochemistry, radioecology, radiation dosimetry and environmental modelling and a smaller, but still important, demand for radiobiologists and bio-modellers. Most of these needs are from government organizations. If only the nuclear industry is considered, then the largest demand is for radiochemists and radiation protection dosimetrists. Given this spectrum of need and existing capacity in the areas of radiobiology it was concluded that the needs identified would be most efficiently met by three new degree programs: • European MSc Radiation Protection • European MSc Analytical Radiochemistry • European MSc Radioecology. All three master programs would be developed using the framework provided by the Bologna Convention and the lecturing could be shared among specialist Scientists within a network of collaborating universities. Therefore, educational plans have been developed for the above MSc degrees. These plans envisage each degree comprising three modules that are common to all the degrees (3×10 ECTS credits), three specialist modules (3×10 ECTS credits) and a research project (1×60 ECTS credits). The courses should be aimed, not only to fill the identified European postgraduate education gap in radiological sciences, but also to provide a modular structure that is easily accessed by stakeholders for CPD training. It is anticipated that the European Masters will meet the academic training requirements of qualified experts”, as defined by the European Commission and the IAEA. At the Norwegian University of Life Sciences (UMB) a pilot MSc in Radioecology has successfully been initiated in collaboration with UK and France. [ABSTRACT FROM AUTHOR]

We present different examples where a quantum dynamical approach to photoinduced processes can reveal features and give answers not available only on the ground of static computations of the potential energy surfaces (PES). We face with different processes of great biological relevance and namely the retinal photoisomerization and the internal conversion in monomers and dimers of DNA nucleobases. Depending on the case, we compute dynamics on a single or on coupled excited electronic states, with PES obtained by first-principle calculations or provided by model Hamiltonians. [ABSTRACT FROM AUTHOR]

This contribution describes molecular dynamics, semi-empirical and ab-initio studies of the primary photo-induced electron transfer reaction in DNA photolyase. DNA photolyases are FADH--containing proteins that repair UV-damaged DNA by photo-induced electron transfer. A DNA photolyase recognizes and binds to cyclobutatne pyrimidine dimer lesions of DNA. The protein repairs a bound lesion by transferring an electron to the lesion from FADH-, upon photo-excitation of FADH- with 350–450 nm light. We compute the lowest singlet excited states of FADH- in DNA photolyase using INDO/S configuration interaction, time-dependent density-functional, and time-dependent Hartree-Fock methods. The calculations identify the lowest singlet excited state of FADH- that is populated after photo-excitation and that acts as the electron donor. For this donor state we compute conformationally-averaged tunneling matrix elements to empty electron-acceptor states of a thymine dimer bound to photolyase. The conformational averaging involves different FADH--thymine dimer confromations obtained from molecular dynamics simulations of the solvated protein with a thymine dimer docked in its active site. The tunneling matrix element computations use INDO/S-level Green's function, energy splitting, and Generalized Mulliken-Hush methods. These calculations indicate that photo-excitation of FADH- causes a π→π* charge-transfer transition that shifts electron density to the side of the flavin isoalloxazine ring that is adjacent to the docked thymine dimer. This shift in electron density enhances the FADH--to-dimer electronic coupling, thus inducing rapid electron transfer. [ABSTRACT FROM AUTHOR]

This contribution describes a new implementation of a general hybrid approach with a modular structure (called COBRAMM: Computations at Bologna Relating Ab-initio and Molecular Mechanic Methods) that is able to integrate some specialized programs and acts as a flexible computational environment, thus increasing the flexibility/efficiency of both QM, and MM, and QM/MM calculations. Specifically, QM/MM ground and excited states geometry optimizations, frequency calculations, conical intersection searches and adiabatic/non-adiabatic molecular dynamics can be performed on a large molecular system, that can be split up to three different layers corresponding to different levels of accuracy. [ABSTRACT FROM AUTHOR]

The nanok calculus has been recently introduced in [1] as a tool for the modeling and simulation of the behaviour of nano devices. Its basic components are molecules specified in terms of an interface and a set of fields. The interface is used to represent the bonds between the specified molecule and the other molecules in the nano device. The fields, on the other hand, describe the internal state of the molecule. The dynamics is modeled by means of reactions defined in terms of rewriting rules applied to pairs of abstractly specified molecules. In this paper we discuss the comparison between the nanok specification and the traditional specification of a two-station rotaxane [2], a versatile molecular shuttle currently used as a building block for more complex nano devices. [ABSTRACT FROM AUTHOR]

We have calculated the static dipole polarizabilities of stoichiometric AlnPn clusters with n = 2–9 at HF, B3LYP, B3PW91 and mPW1PW91 levels of theory using basis sets of increasing size. Our results show that AIP clusters behave like the well studied GaAs clusters and their per-atom polarizabilities decrease rapidly with cluster size. At HF and the DFT levels the per-atom-mean polarizability saturates with size after n = 4. Finally, from the methodological viewpoint, our results show that for those clusters, the different hybrid density functionals we used converge in the computation of the per-atom-mean polarizability as the size of the cluster increases. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the photoisomerization processes of azobenzene after its excitation in the bright S(ππ*). By state of the art/ ab initio/ Complete Active Space calculations followed by perturbative corrections (CASPT2//CASSCF) we have identified the critical structures, the Minimum Energy Paths originating on the bright S(ππ*) and on other relevant excited states including the state S1(nπ*). The seams of conical intersections that are important in guiding the photoreaction are determined. We aim at establishing the mechanism of decay and of photoisomerization for the S(ππ*) state and at explaining the difference between the quantum yields found for the two lowest energy S1(nπ*) and S(ππ*) excited states. We found that an excited state based on the πN = NπN = N→πN = N*πN = N* configuration is a photoreaction intermediate that plays a very important role in the decay the bright S(ππ*). This doubly excited state, by driving the photoisomerization along the torsion path and by inducing a fast internal conversion to the S1(nπ*) occurring in a variety of geometries, explains all the most important features of the S(ππ*) azobenzene photoisomerization. [ABSTRACT FROM AUTHOR]

The mechanism of electron transfer (ET) from reduced pheophytin (Pheo-) to the primary stable photosynthetic acceptor, a quinone (Q) molecule, is addressed by using high-level ab initio computations and realistic molecular models. The results reveal that the ET process involving the (Pheo-+Q) and (Pheo+Q-) oxidation states can be essentially seen as an ultrafast radiationless transition between the two hypersurfaces taking place via conical intersections (CIs) and it is favoured when the topology of the interacting moieties make possible some overlap between the lowest occupied molecular orbitals (LUMO) of the two systems. Thus, it is anticipated that large scale motions, which are difficult to monitor experimentally, may actually occur in the photosynthetic reaction centers of bacteria, algae, and higher plants, to fulfil the observed ultrafast ET processes. [ABSTRACT FROM AUTHOR]

The truncated configuration interaction (CI) approximations of the Hamiltonian eigenstates suffer from lack of simultaneous accuracy: If they are orthogonal as a result of optimization of one state, the other states are poorly approximated; and if they are independently optimized, then they cease to be mutually orthogonal. The fact that: Among all functions, orthogonal to an approximate ground state, the one closest to the (unknown) exact first excited state, of the same symmetry, has lower energy than the exact, leads to the conclusion that: Minimizing the energy of a first excited state approximation, orthogonally to an approximate ground state, should be avoided, because it will depart, instead of approaching, the exact first excited state. Further analysis suggests a method to construct CI approximations of the ground and of the first excited state, which are mutually orthogonal and both closer to the exact than the independently optimized (non-orthogonal) ones. [ABSTRACT FROM AUTHOR]

The truncated configuration interaction (CI) approximations of the Hamiltonian eigenstates suffer from lack of simultaneous accuracy: If they are orthogonal as a result of optimization of one state, the other states are poorly approximated; and if they are independently optimized, then they cease to be mutually orthogonal. The fact that: Among all functions, orthogonal to an approximate ground state, the one closest to the (unknown) exact first excited state, of the same symmetry, has lower energy than the exact, leads to the conclusion that: Minimizing the energy of a first excited state approximation, orthogonally to an approximate ground state, should be avoided, because it will depart, instead of approaching, the exact first excited state. Further analysis suggests a method to construct CI approximations of the ground and of the first excited state, which are mutually orthogonal and both closer to the exact than the independently optimized (non-orthogonal) ones. [ABSTRACT FROM AUTHOR]

A new dynamical clustering algorithm for the identification of modules in complex networks has been recently introduced [1]. In this paper we present a modified version of this algorithm based on a system of chaotic Rössler oscillators and we test its sensitivity on real and computer generated networks with a well known modular structure. [ABSTRACT FROM AUTHOR]

We introduce a novel method for identifying the modular structures of a network: this problem is described as a process of compression of information, by means of the autoencoder frame. As a result, the best partition in modules is found to be the maximizer of an objective function: the ratio association. The performance of the proposed method is shown on a real data set and on simulated networks. The optimization algorithm we use is based on the deterministic annealing scheme. [ABSTRACT FROM AUTHOR]

This contribution describes a new implementation of a general hybrid approach with a modular structure (called COBRAMM: Computations in Bologna Relating Ab-initio and Molecular Mechanics Methods) that is able to integrate some specialized softwares and acts as a flexible computational environment, thus increasing the flexibility/efficiency of both QM, and MM, and QM/MM calculations. Specifically, QM/MM ground and excited states geometry optimizations, frequency calculations, conical intersection searches and adiabatic/non-adiabatic molecular dynamics can be performed on a large molecular system, that can be split up to three different layers corresponding to different levels of accuracy. Here we report, together with a description of the method and its implementation, some test examples on very different chemical problems, which span the wide and diversified area of chemistry (from ground to excited states topics) and show the flexibility, general applicability and accuracy of the presented hybrid approach in the modelling of complex molecular architectures. [ABSTRACT FROM AUTHOR]

A comprehensive modular assembly system model has been proposed that extends the art from modular hardware, to include in-space assembly, servicing and repair and it’s critical components of infrastructure, agents and assembly operations. Benefits of modular assembly have been identified and a set of metrics defined that extends the art beyond the traditional measures of performance, with emphasis on criteria that allow life-cycle mission costs to be used as a figure of merit (and include all substantive terms that have an impact on the evaluation). The modular assembly approach was used as a basis for developing a Solar Electric Transfer Vehicle (SETV) concept and three modular assembly scenarios were developed. The modular assembly approach also allows the SETV to be entered into service much earlier than competing conventional configurations and results in a great deal of versatility in accommodating different launch vehicle payload capabilities, allowing for modules to be pre-assembled before launch or assembled on orbit, without changing the space vehicle design. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Bacteriorhodopsin (BR), a membrane protein found in Halobacterium salinarum, functions as a light-driven proton pump. The Schiff base region has a quadropolar structure with positive charges located at the protonated Schiff base and Arg82, and counterbalancing negative charges located at Asp85 and Asp212 (Figure 1A). It is known that BR lacks a proton-pumping activity if Asp85 or Asp212 is neutralized by mutation. On the other hand, binding of C1- brings different effects for pumping functions in mutants at D85 and D212 position. While C1--bound D85T and D85S pump C1-, photovoltage measurements suggested that C1--bound D212N pumps protons at low pH. In this study, we measured low-temperature FTIR spectra of D85S and D212N containing various halides to compare the halide binding site of both proteins. In the case of D85S, the N-D stretching vibrations of the Schiff base were halide-dependent. This result suggests that the halide is a hydrogen-bond acceptor of the Schiff base, being consistent with the X-ray crystal structure. On the other hand, no halide dependence was observed for vibrational bands of the retinal skeleton and the Schiff base in the D212N mutant. This result suggests that the halide does not form a hydrogen bond with the Schiff base directly, unlike the mutation at D85 position. Halide-dependent water bands in the Schiff base region also differ between D85S and D212N. From these results, halide binding site of both proteins and role of two negative charges in BR will be discussed. [ABSTRACT FROM AUTHOR]

The influence of protein induced chromophore deformations on reaction timescale and quantum yield is investigated using ab initio molecular dynamics in vacuo on four and five double bond models of the retinal chromophore. The opposite twist of the C11 = C12 and the C12-C13 bonds appears to be the prerequisite for the highly stereoselective and efficient cis-trans photodynamics of the retinal chromophore in the binding pocket of rhodopsin. The formation of the photoproduct is determined by the phase of the hydrogen out-of-plane mode of the 11-cis double bond. [ABSTRACT FROM AUTHOR]

This work presents the results of the computational studies for the photochemical activity of phytochromobilin in vacuo with particular attention to the isomerization of the exocyclic double bonds. The spectroscopic state has been characterized and fully unconstrained optimizations on S1 have been performed to investigate the possible deactivation paths. In fact, while in the protein the mechanism involve the rotation of the C15-C16 bond only, in isolated conditions (i.e. solvent or vacuo) several possible competing photoisomerization paths have been unveiled, which could recover the system to the ground state. [ABSTRACT FROM AUTHOR]

Human Glutathione S-Transferase A3-3(hGSTA3-3) is the most efficient human steroid double-bond isomerase enzyme. It catalyzes the double bond isomerization of Δ5-androstene–3,17–dione (Δ5-AD) and Δ5-pregnene–3,20–dione (Δ5-PD). The isomerization products are the precursors of the steroid hormones testosterone and progesterone. We have carried out a QM/MM study to elucidate some interesting aspects of the enzyme catalytic mechanism. In particular, we have analyzed either a concerted or a stepwise reaction path. Moreover, we have attempted to rationalize the electrostatic effects on the catalytic activity of the residues surrounding the active site. Specifically, we have performed a “finger print” analysis to determine the electrostatic contribution of each aminoacid residue to the global electrostatic term, thus ranking the effect of the various aminoacids in the course of the reaction. In this way, we have highlighted the most important terms affecting the stabilization-destabilization of the enzyme. [ABSTRACT FROM AUTHOR]

We present a combined computational and experimental study on structural and electric properties of recently synthesized heteroaromatic dyes and their simple aggregates. Ab initio and density functional theory calculations are carried out to investigate ground state and excited state properties along with their modulation induced by the solvent described with the implicit solvent polarizable continuum model. The results are compared with experimental data concerning spectroscopic studies. Electronic and vibrational contributions to the first hyperpolarizability and condensed phase effects on these properties are also evaluated for single or selected dimeric chromophore structures. Intermolecular interactions are evaluated both at correlated ab initio level and with simplified atomistic models employing molecular mechanics force fields parametrized, as regard electrostatic interactions, on the basis of ab initio computed partial atomic charges. Specific chromophore orientations are considered and the results of the two procedures are compared. [ABSTRACT FROM AUTHOR]

The contribution to the spectral tuning of the main residues in the Rhodopsine protein is being evaluated by employing high level ab initio quantum chemistry tools and the new Reverse Finger Print (RFP) technique. [ABSTRACT FROM AUTHOR]

This contribution illustrates some features of a new of a newly implemented general hybrid approach. This method, included in the COBRAMM (Computations at Bologna Relating Ab-initio and Molecular Mechanic Methods) suite of programs, has a modular structure that integrates some specialized programs and represents a flexible computational environment that increases the flexibility/efficiency of QM, and MM, and QM/MM calculations. Here we describe some aspects of the geometry optimization procedure and explain some approximations used in the frequency computation. Moreover we present two analysis procedures that allow to rank the contribution of the various aminoacid residues of an enzyme in determining the catalytic mechanism and the shape of a Potential Energy Surface (PES). [ABSTRACT FROM AUTHOR]

We used a new three-layer ONIOM(QM:QM:MM) scheme to probe the protonation state of the Glu-181 residue in the binding pocket of the dark-adapted state of Rhodopsin. Recent experimental evidence has led to conflicting conclusions about the protonation of Glu-181, which has important consequences for the proposed “counterion-switch” mechanism: In particular, the possible role of a proton transfer from Glu-181 to the primary Glu-113 counterion in destabilizing the salt bridge with the retinal protonated Schiff base to form the active meta-II state. By incorporating the interaction of retinal with important binding pocket residues at the QM level, we can calculate accurate structural, NMR, vibrational, and electronic absorption data for charged and neutral Glu-181 models of the dark state of the wild type, and of the E181Q mutant. Comparison of our new results with experiment gives valuable insight into the reliability of experimental methods in determining the protonation state of Glu-181. [ABSTRACT FROM AUTHOR]