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Objective. This study aims to address the issue of long scan durations required by traditional graphical analysis methods, such as the Logan plot and its variant, the reversible equilibrium (RE) Logan plot, for dynamic PET imaging of tracer kinetics. Approach. We propose a relative RE Logan model that builds on the principles of the Logan plot and its variant to significantly reduce scan time without compromising the accuracy of tracer kinetics analysis. The model is supported by theoretical evidence and experimental validations, including two computer simulations and one clinical data analysis. Main results. The proposed model demonstrates a significant linear relationship between the variable x and the slope DVT of the RE Logan plot, and the variable x ′ and the slope D V T ′ of the relative RE Logan plot. The Pearson correlation coefficients (r) of the linear fitting of the x ′ to the x equal 0.9849 in the simulated data and 0.9912 in the clinical data. Similarly, the r values for the linear fitting of D V T ′ to DVT equal 0.9989 and 0.9988 in the simulated data, and 0.9954 in the clinical data. Significance. These results demonstrate the model's capability to maintain strong linear relationships and produce parametric images comparable to the traditional RE Logan plot, but with the considerable advantage of shorter scan durations. This innovation holds significant potential for enhancing the efficiency and feasibility of PET imaging in clinical settings. [ABSTRACT FROM AUTHOR]

This study is based on the applications of many irregularity descriptors (IDs) which help us to discover the irregularity measurements (IMs) in the chemical compound named porous graphene. It is symbolized as PGRz×z, for z = 1, 2, 3 and 4. These IDs and IMs are used in this article to get new bounds for measurements. A graphical depiction and analysis have also been made over the molecular structure of Porous Graphene. Different IMs like IRDIF(ֆz), AL(ֆz), IRL(ֆz), IRLU(ֆz), IRLF(ֆz), IRF(ֆz), IRLA(ֆz), IRD1(ֆz), IRA(ֆz), IRGA(ֆz), IRB(ֆz), and IRRt(ֆz) have been considered. By using above-mentioned descriptors, we will be able to produce new formulas which are related to the IMs in PGRz × z, for z = 1, 2, 3, and 4. [ABSTRACT FROM AUTHOR]

Linear electromechanical actuators are popular in flight servo-actuation systems. Repertories of mandatory acceptance and health-monitoring tests result in the generation of large amounts of data. This poses challenges in handling the volumes of similar data sets by quality/systems health engineers, causing fatigue in making critical decisions. Attempt is made to ease such tasks by representing the data in a pictorial form to easily identify the parameters of interest. This study focuses on the use of Lissajous figures to pictorially represent the acceptance and condition monitoring test data the flight actuators. A graphical interpretation of acceptance test data represented by Lissajous patterns, aimed at the automation of test outcomes, is attempted. The extraction of system health indicators for mechanical faults in electromechanical linear actuators is also attempted. The results will help in developing expert systems taking advantage of current efficient pattern recognition and classification algorithms. This study focuses on easing the critical flight-worthiness clearance jobs of quality engineers and extracting system health parameters from test data represented graphically.

With the increasing of mining depth, the problem of gas outburst becomes increasingly prominent. How to quickly and safely carry out rock cross-cut coal uncovering is an important goal to ensure the safety of coal mine production. In this paper, based on the graphical analysis method, the relevant literatures in the recent 30 years in the database of CNKI are selected as samples to analyze the research hotspots in the field of local outburst prevention of the rock cross-cut coal uncovering. After analyzing the research progress and shortcomings of the measures to outburst prevention, it is found that the low temperature freezing reduce the energy storage of coal seam and improve the strength of coal mass. However, coal strength is crucial to prevent gas disasters, because the occurrence of coal and gas outburst accidents is caused by the energy storage instability of coal seam breaking through the resistance of coal mass. Based on the technical problems existing in the field of local outburst prevention and the shortcomings of artificial freezing method，combined with intelligent technology, an intelligent integration measure of “drilling, pumping and injection” is proposed. Real-time monitoring and early warning are carried out through signal base stations and local area networks to achieve accurate outburst prevention. By combining the establishment of multi-physics coupling model, theoretical analysis and engineering practice verification, the occurrence state and migration law of gas in coal rock mass in freezing condition are mastered, which provides theoretical basis for the application of low temperature freezing technology in the local outburst of rock cross-cut coal uncovering. With the help of intelligent liquid nitrogen freezing system, “one hole multi-function” is realized, which provides a new choice and support for the local anti-outburst work of rock cross-cut coal uncovering, so as to quickly and safely uncover the dangerous coal seam of outburst.

Ready to upgrade cake time? Say goodbye to slice squabbles! Our analytical solution serves up fairness and fun—no more cake hogs allowed. Ever seen cake negotiations? It's like a bakery battlefield. But fear not; the solution makes cake sharing a cakewalk. From a mini cake to a behemoth and from a few friends to a crowd, it will get you covered. Slice stress ends here. Let's cake together; crumb envy is not invited! [ABSTRACT FROM AUTHOR]

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The high-pressure exhaust gas recirculation (HP-EGR) has been well-proven for marine engines complying with the IMO Tier Ⅲ NOx regulation. Considering different turbocharged scavenging schemes and emission control modes, intake and exhaust gas management is critical to the HP-EGR design. However, few theoretical studies on it were reported. This paper aims at providing a case study on the flow characteristic of the turbocharged HP-EGR system. With the proposed topology structure of the typical HP-EGR layout, numerical studies on the turbocharged scavenging and EGR design were conducted based on the 6EX340 two-stroke engine. The result showed that the flow characteristic of the turbocharged two-stroke engine can be graphically depicted by simplifying the cylinder and turbine as multi-nozzle in series. According to the nozzle flow equation of uniflow scavenging, there exists an optimum turbine flow area to maximize the scavenging mass flow. Effects of EGR, cylinder bypass, and exhaust gas bypass on the flow characteristic of the two-stroke engine depend on the turbocharger matching. The out-cylinder scavenging and in-cylinder combustion should be optimized interactively to fully explore the fuel economy and NOx trade-off. Finally, the proposed design procedure can provide good guidance for the design and control of the HP-EGR system.

The influence of three main parameters including irradiation time, weight fraction of photocatalysts including multi-walled carbon nanotubes and different amount of TiO2 (MCT#1 and MCT#2) and pH is investigated for the degradation rate of methyl orange (MO). Analysis of variance (ANOVA) and response surface methodology (RSM) have been applied to study the binary and ternary interactions of the main parameters on the degradation rate. The ANOVA results confirm that all of three studied factors have a considerable efficacy on degradation rate of MO at 5% level of probability. Meanwhile, the results show that the degradation rate is enhanced with increasing the weight fraction in range of 0.1 to 0.3%wt and irradiation time in a period of 5 to 35min.The lowest and highest degradation are observed at pH=7 and pH=3, respectively. The normality of residue distribution can be confirmed using graphical analysis. The RSM results reveal that the degradation rate dependency on irradiation time is higher than the weight fraction of photocatalysts. [ABSTRACT FROM AUTHOR]

The interaction of a sprocket with the links of a drive gear chain is studied by graphical analysis. In gear chains with rolling hinges, the contact pitch of the chain is increased on chain engagement with the sprocket. The contact pitch is changed when the sprocket turns through two angular increments. Change in the contact pitch is undesirable, because it results in nonuniform chain motion. Recommendations are made for decreasing the dynamic loads in a drive with gear chains. [ABSTRACT FROM AUTHOR]

It is well known that Marshall had great difficulty in organizing his work after the Principles. The promised second volume never came, and for the books that eventually were published, Industry and Trade (1919) and Money, Credit, and Commerce (1923), Marshall was at pains to find the right mode of expression for his research. In the introduction to the Principles, Marshall had explained his reliance on partial equilibrium analysis and, more generally, ceteris paribus reasoning as the natural method of the economist, for which his method of diagrams was an excellent fit. But already while working on his Principles Marshall had moved closer to economic history. In a letter of June 1879 to Jevons, he had praised Jevons's statistical work as an important step in "'real'-ising" the abstract theories of economists, in which he promised to follow suit. However, while Jevons tried to flesh out mathematical relations that captured the economic causalities hidden in statistical data, Marshall started to explore a different strategy, a strategy that explains his criticism of "mathematico-statistics" and the waning away of his initial enthusiasm for the method of diagrams as an engine of discovery. Instead of relying on the ceteris paribus method, which would examine one causal factor at a time, Marshall searched for an approach that captured the causalities in the economy as an encompassing whole. A shorthand for this approach is his famous epigraph to Industry and Trade: "The many in the one, the one in the many." Moving away from the opposition between abstract theory and economic facts, Marshall tried to develop a strategy that mediates between the generic categories of the economist and the specific events of history that are the domain of the economic historian. In contrast with the ceteris paribus strategy Marshall embraced in his Principles, in which an incomplete analysis is improved by adding causal factors, Marshall explored what this article calls a narrative strategy, in which he tried to work out how to integrate a manifold of heterogeneous causal factors into a unified whole, thus providing causal coherence to a complete chronology of events. The purpose of my contribution to this issue is to explore the development and substance of this narrative strategy. This article will use Jevons's and Marshall's different cartographies of time as an entry point to understand Marshall's narrative take on the causal explanation of the facts of history. [ABSTRACT FROM AUTHOR]

The existing equations for the discharge coefficient of Piano key weirs (PKWs) use a limited range of experimental data, which means that they are inappropriate for wide parametric ranges that might lead to significant errors. This study aimed to propose a reformed empirical equation using a wide range of data points gathered from previous experimental studies. Further, the appropriateness to use the existing equations for the collected data points, and the related errors, were investigated in detail using graphical and statistical analyses. The proposed equation predicted the discharge coefficients with <5% absolute errors for 83.5% data points and with <10% absolute errors for 100% data points, and the mean absolute error was 2.9%. Such variations may be attributed to the differences in experimental conditions that exist among the previous studies. The correlation indices were higher for the proposed equation as compared to the same for the existing equations, whereas the error indices were lowest for the proposed one. For some very specific parametric ranges, the existing equations still hold better accuracy. Overall, the proposed equation can precisely estimate the discharge coefficient of the basic geometry of Type-A PKWs for a wide parametric range and will be handy in the hydraulic design of such PKWs. [ABSTRACT FROM AUTHOR]

Building information modeling (BIM) has traditionally been considered as a tool for the graphical representation of architectural and engineering projects. This technology has become a key instrument for the development of virtual models that simulate the constructive process and facilitate the analysis of the designed solutions to detect incidents linked to traditional bi-dimensional projects. This article focuses on the use of this technology to optimize the design of MEP (mechanical, electrical, plumbing) facilities and architecture by developing virtual BIM models. Therefore, the purpose of this research is to analyze two experiences of complex buildings that have developed a BIM Execution Plan to improve the coordination of all disciplines involved, in order to explore how these real experiences can contribute to the implementation of the use of this technology in the construction industry. The results of the research are divided into two aspects: on the one hand, the improvements that BIM brings to the coordination and optimization of MEP facilities, linked to the typification of design incidents detected to anticipate conflicts between disciplines, facilitate collaborative design between different agents, keep graphic documentation updated and avoid execution problems and additional costs; and on the other hand, the keys to facilitating the extension of the use of this technology in the industry. Therefore, the conclusions of the research point out to the need for improvement in the automation of incident detection and the reduction in design process deadlines, as well as the need to simplify the virtual modeling process to bring it closer to unqualified personnel involved in the workflow and facilitate the implementation of this technology in the construction industry. [ABSTRACT FROM AUTHOR]

The nonlinearities inherent in the mechanics of origami make it a rich design space for multistable structures and mechanical metamaterials. Here, we investigate the multistability of a classic origami base: the symmetric eightfold waterbomb. We prove that the waterbomb is bistable for certain crease properties, and derive bounds on, and closed-form approximations of, its stable states. We introduce a simplified form of the waterbomb kinematics and present a design procedure for tuning the depth and the symmetry/asymmetry of its energy wells. By incorporating the concept of pretensioned torsional springs, we also demonstrate the existence of tristable cases for the waterbomb fold pattern. We then apply the analysis of a single waterbomb to study quasione-dimensional arrays of waterbombs, where we discover a conserved geometric-kinematic quantity in which the number of popped-up and poppeddown vertices is determined uniquely through analysis of the origami structure's boundaries. This culminates with a discussion of how the quasi-onedimensional array may be designed to achieve stable states with various degeneracies, kinematics and gaps between energy levels. Collectively, this work presents an alternative approach for characterizing origami multistability properties and reveals an origami design motif that has potential applications in physically reconfigurable structures, mechanical energy absorption and metamaterials. [ABSTRACT FROM AUTHOR]

Investigating the interaction of genotype and environment in multi‐environment experiments (MET) is one of the reliable techniques to demonstrate the most stable and compatible cultivars. The main contribution of this study is to evaluate the stability and compatibility of rapeseed cultivars using additive main effects and multiplicative interaction (AMMI) and genotype plus genotype environment interaction (GGE) bi‐plot methods for grain yield and oil content. For this purpose, an experiment in a randomized complete block design (RCBD) with three replications was conducted for 10 rapeseed cultivars across 10 environments (five regions in 2 years). Hence, the proposed technique can be used to identify the superior cultivars corresponding to the multivariant properties including yield and oil content. To do so, a case‐study analysis was conducted over rapeseed, while more than 96% of the data variance for grain yield and more than 94% of the data variance for oil content were explained based on the AMMI model. According to the AMMI model, it was observed that the "Zarfam" and "Licord" genotypes were introduced as favorable genotypes for grain yield and oil content, respectively. "Karaj1" and "Sanandaj1" were selected as the superior environments for yield trait, "Kashmar2" for oil content, and "Licord" and "Kashmar2" were identified as the superior genotypes and environment for oil content, respectively. Graphical GGE bi‐plot illustrated that "Hyola401," "Okapi," and "Sarigol" for grain yield and "Option500" and "Sunday" for oil content were identified as stable and high‐yield genotypes. "Sanandaj1" for grain yield and "Karaj2" for oil content were identified as environments with high differentiation and screening power. [ABSTRACT FROM AUTHOR]

The kerf taper angle is one of the most significant parameters for AWJ cutting. Choosing the best cutting parameters is critical to reducing the kerf taper. Therefore, the aim of this work is to demonstrate on to implement RSM in conjunction with the Rat swarm optimizer algorithm to optimize the kerf taper angle of a Titanium alloy. Thirty-two number of experiments were conducted according to CCD considering five process parameters namely jet traverse rate, water jet pressure, abrasive flow rate, stand-off distance and diameter of focusing nozzle to achieve kerf taper angle. A second-order full quadratic model is used for mathematical modeling. The result demonstrates that the model is sufficiently adequate and acceptable. A recent Rat Swarm Optimization (RSO) algorithm is considered for finding out the global optimal solution. It is observed that after optimizing the process that the jet traverse rate of 1.952 mm/sec, water jet pressure of 250.548 MPa, abrasive flow rate of 0.554 kg/min, stand-off distance of 3.75 mm and diameter of focusing nozzle of 2.0 mm gives minimized with 0.754 degree of kerf taper angle. A series of verification tests are carried out to ensure that the optimization technique is accurate in determining the best levels of process. [ABSTRACT FROM AUTHOR]

Wheat is one of the main cereals. At this time, the crucial difficulty in improving nutritional traits is the influence on genotypes of different environments. Selecting superior genotypes on the basis of a gene effects analysis for varying environments is demanded. In this study, 10 different genotypes of bread wheat (Triticum aestivum L.) were used. Parents, hybrids, and two standard checks were evaluated in a complete randomized block design with three replicates in four environments: E1 and E2 (normal and late sown, Rabi 2018-19) & E3 and E4 (normal and late sown, Rabi 2019-20). The analysis of the components of the gene effect revealed that most of the characters were governed by additive and dominant gene actions in the environments; for gluten, the wet gluten (E2) and starch (E3) content were the only dominant components (H1 and H2) with a significant gene effect. Overdominance, asymmetrical distribution of positive–negative and dominant–recessive genes, and narrow-sense heritability were observed in most of the characters in all environments. In a graphical analysis, the regression value b was observed to be in unity among protein content (E1 and E3), sedimentation value (E1, E2, and E3), and starch content (E1), indicating the absence of digenic interactions. Based on the intercept of the regression line on the Wr axis, the degree of dominance for protein content (E1 and E3), sedimentation value (E1, E2, and E3), and starch content (E1) was depicted as overdominance. Therefore, a given population may be improved to isolate superior recombinants for the development of desired parents in future breeding programs. [ABSTRACT FROM AUTHOR]

Production of precipitated calcium carbonate (PCC) by indirect carbonation of BOF (Basic Oxygen Furnace) slag usually requires a calcium extraction stage to promote the dissolution of calcium. Previous works have shown that the grinding of BOF slag to smaller particle size accelerates calcium leaching at the expense of a high energy input and further environmental constraints such as dust management. In order to minimize the excessive consumption of energy due to grinding, this study focused on the optimization of calcium extraction from unmilled BOF slag using ammonium chloride (NH4Cl) and ammonium nitrate (NH4NO3). The study was conducted with a solvent-to-slag mass ratio of 10/1, to avoid the dissolution of impurities such as iron, silicon, magnesium and manganese and guarantee minimum equipment costs. The results obtained using umilled BOF slag show that the efficiency of calcium extraction reached ~75% for NH4NO3 and ~69% for NH4Cl in two extraction stages. A calcium carbonate precipitation yields of 80% was reached at 25°C and 6.5bars. Scanning Electron Microscopy (SEM) analysis of the dry PCC obtained showed that it is mostly dependent on the flow rate of CO2 and the carbonation pressure. Finally, the PCC was evaluated for the treatment of acid mine drainage.

Building information modeling (BIM) has traditionally been considered as a tool for the graphical representation of architectural and engineering projects. This technology has become a key instrument for the development of virtual models that simulate the constructive process and facilitate the analysis of the designed solutions to detect incidents linked to traditional bi-dimensional projects. This article focuses on the use of this technology to optimize the design of MEP (mechanical, electrical, plumbing) facilities and architecture by developing virtual BIM models. Therefore, the purpose of this research is to analyze two experiences of complex buildings that have developed a BIM Execution Plan to improve the coordination of all disciplines involved, in order to explore how these real experiences can contribute to the implementation of the use of this technology in the construction industry. The results of the research are divided into two aspects: on the one hand, the improvements that BIM brings to the coordination and optimization of MEP facilities, linked to the typification of design incidents detected to anticipate conflicts between disciplines, facilitate collaborative design between different agents, keep graphic documentation updated and avoid execution problems and additional costs; and on the other hand, the keys to facilitating the extension of the use of this technology in the industry. Therefore, the conclusions of the research point out to the need for improvement in the automation of incident detection and the reduction in design process deadlines, as well as the need to simplify the virtual modeling process to bring it closer to unqualified personnel involved in the workflow and facilitate the implementation of this technology in the construction industry.

Animal models of Parkinson's disease are useful to evaluate new treatments and to elucidate the etiology of the disease. Hence, it is necessary to have methods that allow quantification of their effectiveness. [18F]FDOPA‐PET (FDOPA‐PET) imaging is outstanding for this purpose because of its capacity to measure changes in the dopaminergic pathway noninvasively and in vivo. Nevertheless, PET acquisition and quantification is time‐consuming making it necessary to find faster ways to quantify FDOPA‐PET data. This study evaluated Male Wistar rats by FDOPA, before and after being partially injured with 6‐OHDA unilaterally. MicroPET scans with a duration of 120 min were acquired and Patlak reference plots were created to estimate the influx constant Kc in the striatum using the full dynamic scan data. Additionally, simple striatal‐to‐cerebral ratios (SCR) of short static acquisitions were computed and compared with the Kc values. Good correlation (r > 0.70) was obtained between Kc and SCR, acquired between 80–120 min after FDOPA administration with frames of 10 or 20 min and both methods were able to separate the FDOPA‐uptake of healthy controls from that of the PD model (SCR −28%, Kc −71%). The present study concludes that Kc and SCR can be trustfully used to discriminate partially lesioned rats from healthy controls. [ABSTRACT FROM AUTHOR]

In this work we propose a semi-supervised framework to visually assess the progression of time series. To this end, we present a recurrent version of the VAE to exploit the generative properties that lead it to learn in an unsupervised way a continuous compressed representation of the data. We introduce a classifier in the VAE training process to control the regulation of the latent space, allowing the network to learn latent variables that set the basis for creating an explainable evaluation of the data. We use the proposed framework to address the diagnosis of Atrial Fibrillation (AF) first validating it with simulated data with known properties and subsequently testing it with intracardiac data obtained from pacemakers and defibrillator systems.

Abstract The present study investigates the determinants of vehicle dwell time at stations in urban light rail networks. Using data collected from an on-board automatic passenger counting system of the tramway network of the French city of Nantes over a long period, the study performs graphical and statistical analyses enabling the identification of cause-and-effect relationships of a number of attributes on the dwell time and its reliability. The results confirm the significance of the boarding and alighting passenger volumes, as well as of the on-board passenger loading, on the dwell time. Additional effects on dwell time are found from the vehicle type (low- or high-floor), the time of day (peak, off-peak, inter-peak) and the location of the station (city centre, proximity to points of interest). Also, it is found that operations are not symmetrical, and dwell times tend to be higher in one direction than the other of the same line. Finally, the results suggest that dwell time reliability is lower for stations located further from the starting terminal, or for stations located in the city centre.

The plankton algae species composition in the technogenic reservoir and the changes observed after the cessation of industrial exploitation have been studied using Lake Shlamonakopitelnoe as an example (Vasilievskie Ozera lake system, Samara Region, Russia). Comparison of the species composition and taxonomic structure of phytoplankton during the period of active industrial exploitation (1991–1992) and the post-exploitation period (2001) revealed an increase in the algae species richness and an increased complexity of the taxonomic structure. Therefore, this was the positive transformation of the phytoplankton community. The high species specificity of algoflora and the low level of species continuity in each study period indicated a significant degree of ecosystem transformation against the background of cessation of exploitation.

Guarini first develops a rigorous and systematic discourse on vaulted systems. In three treatises: Architettura Civile, Euclides adauctus, and Modo di misurare le fabriche, he described the geometric nature of the vaults, the principles of geometry and their practices in the stereotomy, and the measurement of the vaults’ surfaces and volumes, respectively. In this paper, moving from previous studies, the significant relationships between the Architettura Civile and Modo di misurare le fabriche are deepened, also in light to the theoretical bases established in the Euclides adauctus. Graphical analyses and reconstructive digital models, linking the texts to the original diagrams and drawings of the treatises, allow to highlight the role of geometry in Guarini’s theorization and the logic of shapes’ composition at the basis of his inventions, and constitute a knowledge base to recognize and interpret the geometric structure of the vaults in Baroque built heritage.

Numerous methods have been proposed as measures of quality of glycemic control resulting in confusion regarding the best choice of metric to use by clinicians and researchers. Some methods use a single metric such as HbA1c, Mean Glucose, %Time In Range (%TIR), or Coefficient of Variation (%CV). Others use a combination of up to seven metrics, for example, Q-Score, Comprehensive Glucose Pentagon (CGP), and Personal Glycemic State (PGS). A recently proposed Composite continuous Glucose monitoring index utilizes three metrics: %TIR, Time Below Range (%TBR), and standard deviation (SD) of glucose. This review proposes that only two metrics can be sufficient when monitoring an individual patient or when comparing two or more forms of management interventions. These two metrics comprise (1) a measure of efficacy such as Mean Glucose, HbA1c, %TIR, or %Time Above Range (%TAR) and (2) a measure of safety based on risk of hypoglycemia such as %TBR, Low Blood Glucose Index (LBGI), or frequency of specified types of hypoglycemic events per patient year. By analysis of the two-dimensional graphical and statistical relationships between metrics for safety and efficacy and by testing identity versus nonidentity of these relationships, one can improve sensitivity for detection of the effects of medications and of other therapeutic interventions, avoid the need for arbitrary scoring systems for glucose values falling within versus outside the target range, and offer the advantage of conceptual and practical simplicity. [ABSTRACT FROM AUTHOR]

The Pareto and the Log-normal distributions can be characterised by having constant inequality curves. After providing formal proofs, these results will be exploited to obtain graphical and analytical tools for analysis and goodness-of-fit tests for these distributions. Order-statistics-based estimators of the curves will be presented and discussed. Examples with simulated and real-data will be used to show how the tools presented work in practice. [ABSTRACT FROM AUTHOR]