Design Decisions Research Articles

Probabilistic Safe WCET Estimation for Weakly Hard Real-time Systems at Design Stages

Weakly hard real-time systems can, to some degree, tolerate deadline misses, but their schedulability still needs to be analyzed to ensure their quality of service. Such analysis usually occurs at early design stages to provide implementation guidelines to engineers so they can make better design decisions. Estimating worst-case execution times (WCET) is a key input to schedulability analysis. However, early on during system design, estimating WCET values is challenging, and engineers usually determine them as plausible ranges based on their domain knowledge. Our approach aims at finding restricted, safe WCET sub-ranges given a set of ranges initially estimated by experts in the context of weakly hard real-time systems. To this end, we leverage (1) multi-objective search aiming at maximizing the violation of weakly hard constraints to find worst-case scheduling scenarios and (2) polynomial logistic regression to infer safe WCET ranges with a probabilistic interpretation. We evaluated our approach by applying it to an industrial system in the satellite domain and several realistic synthetic systems. The results indicate that our approach significantly outperforms a baseline relying on random search without learning and estimates safe WCET ranges with a high degree of confidence in practical time (< 23 h).

Optimisation of topology, rating, control and insulation coordination of a large series–parallel DC windfarm

AbstractThis study presents the design of a large DC series‐parallel windfarm that considers the key operational challenges in determining the optimal generator equipment rating and DC transmission voltage control. With this topology, offshore platform is not needed, but wind speed dispersion over windfarms and generator outage possibilities demand generator DC output voltages beyond their ratings. An optimization algorithm is developed along with a complete cost model, which includes operational and capital costs with all topology options, in order to inform design decisions. The results are evaluated on a 100‐generator, 25 × 4, 1 GW, 525 kV test wind farm and performance is verified using detailed PSCAD/EMTDC time‐domain simulation. The key finding is that a positive net present value (NPV) is achieved, avoiding power curtailment even under 3% generator outage, when an overvoltage coefficient of 1.145 pu is utilised on all wind generators, assuming use of a suitable DC transmission voltage control. Further, a wide‐ranging parameter sensitivity analysis is performed, and tower arrangement for insulation requirements is proposed.

Role of Graphic Design in Computer Polygraphic Research: Influence of Design Decisions on Product Production and Use

The purpose of the article is to find out the role of graphic design in computerised printing processes and evaluate how the choice of design decisions affects the production and functionality of finished printing products. Research methodology. The research used theoretical analysis to study literary sources, scientific publications and historical data on the development of graphic design and its impact on the printing industry. Empirical observation, such as data collection through observation of work processes in design studios and printing houses, analysis of real cases of implementation of design solutions were applied. Comparative method was used to compare the effectiveness of different design approaches and their impact on the final product. Case analysis, as a detailed analysis of specific projects where innovative design solutions was applied, and evaluation of their impact on product success. Scientific novelty consists in the fact that the impact of graphic design on printing production and its perception by consumers has been investigated. It has been established that design solutions affect the efficiency and attractiveness of products. The processes of merging graphic design with computer polygraphic processes were studied, from the perspective of the formation of changes in design work, and it was determined for the first time that modern visual trends affect the interactivity and emotional perception of users. Conclusions. It was determined that polygraphic complexes form a unique corporate style that communicates with other design elements through clear visual images. Graphic design reproduces reality through a creative combination of colour, shape and texture, creating a subjective worldview. Simplicity and clarity are key to effective visual communication. Artistic images, which become full-fledged graphic objects in design, depend on visual perception and psychology, and are subject to various transformations to achieve the desired effect in printed products. Keywords: computer printing, graphic design, digital design, artistic method, printing product.

State of the art in determining the optimal reverse logistics network for your product

The primary focus of this study is to explore and answer the following research question: “In what ways can organizations enhance the efficiency and responsiveness of their reverse logistics network design?” The study presents a conceptual framework that the authors have built, incorporating several essential variables to guide the process of network design. The conceptual framework for reverse logistics networks has been developed by conducting an analysis of the fundamental factors that influence network design decisions. This paradigm facilitates the decision-making process for firms when considering the centralization or decentralization of their reverse logistics operations and the outsourcing or insourcing of specific operational aspects. Moreover, the authors have discovered and highlighted relevant literature that exhibits strong alignment with our proposed framework, hence offering useful insights for decision-making in the domain of reverse logistics network design. Within our framework, two crucial dimensions are considered at each stage: the choice between internal processing vs . outsourcing and the decision to centralize or decentralize operations. With consideration of the factors noted above, this paper proposes a mixed integer linear programming model for the design of a reverse logistics network. This model aims to minimize the total cost at each stage of reverse logistics operations.

Реализация экологических проектов Госкорпорацией «Росатом»

Key projects to eliminate the accumulated environmental damage in the Leningrad and Irkutsk regions are presented. They are implemented by the Rosatom State Corporation enterprise, the Federal State Unitary Enterprise “Federal Environmental Operator” (FSUE “FEO”). The main technological approaches used for the remediation of contaminated areas on the example of the Krasny Bor landfill in the Leningrad region, the former chemical enterprise Usolyekhimprom LLC and the Baikal pulp and paper mill in the Irkutsk region are given. Design decisions to eliminate accumulated environmental damage are reasonable, effective, reliable and environmentally safe. The need to re-involve the remediated territories into economic circulation was noted.

Sustainable Vehicle Design Considering Quality Level and Life Cycle Environmental Assessment (LCA)

One of the global ecological problems is the excessive carbon dioxide emissions generated by vehicles in the transport sector, including passenger transport. Therefore, the objective of this investigation was to develop a model that supports the prediction of vehicle variants that will be satisfactory to the customer in terms of: (i) quality level and (ii) environmental impact throughout the life cycle. This model was developed with the following techniques: TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution), LCA (Life Cycle Assessment), SMARTER (Specific, Measurable, Achievable, Relevant, and Time-bound), Pareto–Lorenz, and the Multi-Criteria Decision Method rule (7 ± 2). A model test was carried out for production variants of the electric vehicle BEV (battery electric vehicle) for which the quality level and life cycle assessment were estimated. Vehicle quality levels ranged from 0.15 to 0.69, with a weight of 0.75. However, vehicle life cycle scores were estimated in the range of 0.25 to 0.57, with a weight of 0.25. Ultimately, the level of the vehicles’ LCA ranged from 0.18 to 0.62. As a result, it was shown that on the basis of various modifications of the quality level of vehicle variants and the corresponding environmental impacts throughout their life cycle, it is possible to predict the vehicle variant that is most satisfactory for the customer and, at the same time, environmentally friendly. The originality of the model relies on supporting the making of sustainable design decisions and the planning of vehicle improvement actions according to customer expectations. Therefore, the model can be used to analyse different types of vehicles by producers and dealers of these products.

Features of a finite-element modeling of a tubular tower for a wind-power unit

Introduction. Being indisputably relevant, an identification of the features of modeling tower structures can simplify the work of engineers and simultaneously move the design decision-making to a qualitatively new level.Aim. To assess the effect, caused by some particular features of a computational modelling, on the resulting parameter, representing the frequency behavior of a tubular tower for wind-power units.Materials and Methods. Numerical studies were conducted using a domestic SCAD Office programming and computing suite. In computational modeling, 41st, 42nd, 44th and 50th FE types were used. During the assessment of effects, caused by the finite element type, calculations of a cylindrical tower with fixed parameters were performed, taking into account variations in the type and size of the FE. Estimating factors in calculations included: variations in stresses, as well as in the frequency of first-mode natural oscillations. During the comparison of stress values, the plate of the third from the fixed base row was taken as the design one. Turbowind T600-48 and Eviag EV 100 were considered as wind turbines.Results. A sufficient discretization value of the computational model for determining the frequency of natural oscillations equals to nR = 12, since a further increase in the value of nR will lead to variations in the frequency of natural oscillations by less than 1%. The individual frequencies of 0.275 and 0.825 Hz were determined for an Eviag EV 100 wind turbine. For a Turbowind T600-48, the range of resonant frequencies is determined due to the presence of a variable rotor speed: starting and maximum frequency ranges of 0.255–0.765 and 0.383–1.149 Hz, respectively.Conclusions. During the modeling of a tower in the SCAD Office PCS, it is feasible to use the 44th type of finite elements, taking into account the obtained sufficient discretization value. The obtained spectrum of natural and resonant frequencies allows avoiding the appearance of a resonant effect when making design decisions.

Analisis Kinerja Web Disdukcapil Dengan Menggunakan Heuristic Evaluation Dan Webuse Web Performance Analysis with Heuristic Evaluation and Webuse

The Disdukcapil website of South Lampung Regency is a service access to a website that has moved to serve the community for every complaint of the community and information that can be accessed online. Since this website has been operating, there has never been a change or evaluation. This study uses web-based methods and heuristic evaluation. Webuse can calculate the user's individual satisfaction and assessment of websites using structured and accurate tools, while the calculation of heuristic evaluation aims to determine guidelines, general principles, and/or regulations that can guide design decisions and/or be used in evaluation and provide criticism and suggestions on decisions that are made. This research was conducted by spreading questions to 50 respondents. The results of the Heuristic Evaluation of Webuse (Heuristic Evaluation) on the Disdukcapil website in South Lampung Regency have met usability requirements efficiently and effectively and provide freedom to users in using the Disdukcapil website in South Lampung Regency. The evaluation results that have been carried out on the recommendations are adrift with the "excellent" performance and effectiveness interface. Each category is added up and divided by the category itself, producing the usability level of the South Lampung Disdukcapil website at the highest "good" level, namely the "aesthetic and minimalist design variable (H8) excellent." Savery values become 1 in the category of cosmetic problems; the errors found are included in the category that do not need to be repaired unless the website work time is still available. Based on the conclusions above, it can be seen that overall, the South Lampung Disdukcapil website is included in the minor usability problem category.

A Data-Centric Approach to Loss Mechanisms

Abstract Breaking down the total loss in a turbomachine into a number of low-order, physical models is a powerful way of developing loss models for informing design decisions. Better loss models lead to better design decisions. A problem, however, is that in complex flows, it is often not clear how to break a flow down physically without making assumptions. An additional problem is that the designer often does not know what assumptions should be made to derive the most accurate and general physical models. In practice, this problem often leads to loss models of low accuracy, which only work in a limited part of the overall design space. This paper shows that machine learning can be used to augment a designer in the process of developing loss models for complex flows. It is shown that it is able to help a designer discover new, more accurate and general, physical models, highlighting to a designer what assumptions should be made to retain the physics important to the problem. The paper illustrates the new method using the problem of compressor and turbine profile loss. This problem was chosen because it is well understood and therefore is a good way of validating the new method. However, surprisingly the new method is shown to be able to develop a new profile loss model which is more accurate and general than previous models. This is shown to have been achieved by the machine learning finding a new, more general, underlying model for trailing edge mixing loss.

Document theory and document design

This paper reports on an experiment which connects document design with document theory. Document design is about what documents should do. We use the example of document graphs and of Cosma, a visualization program created during the HyperOtlet research programme, to show how theory can inform design decisions and help conceptualize results.

Supporting early-stage design decisions with building performance optimisation: Findings from a design experiment

Building performance optimisation (BPO) has been intensively explored due to its potential in improving building performance and design efficiency. However, studies on its application in supporting early-stage design decisions are rather limited, causing its actual effectiveness to remain questionable. This paper addresses the problem through a design experiment, where participants designed an office building for energy efficiency, using first the conventional method and then BPO. They also evaluated others' design outcomes and completed a questionnaire about the experiment afterwards. The results showed that BPO is effective in supporting early-stage architectural design even for novices. It turned manual designs that are often averagely energy-efficient in the solution space into top designs without significantly affecting other design merits. The average energy use intensity (EUI) decreased by 8.5 % in this experiment. However, it showed a narrow advantage (0.5 % on average) over evaluating a series of design samples and no clear superiority over less-automated supporting methods with more involvement of designers, as its effectiveness is limited by technical difficulties in implementing certain variables strongly correlated with energy efficiency. In addition, while the majority of participants acknowledge the effectiveness of BPO and the acceptance of its design outcomes, manual designs were still preferred by more, mostly for better aesthetics and better alignment of design concepts, implying the necessity of designer's interventions before using BPO outcomes in design practice. The useability of BPO also needs to be improved by shortening the calculation time and lowering the difficulties in building desirable parametric models.

СОЗДАНИЕ СИСТЕМ УПРАВЛЕНИЯ СОСТОЯНИЕМ ДОРОЖНЫХ КОНСТРУКЦИЙ КАК ЭФФЕКТИВНОГО ИНСТРУМЕНТА ПОВЫШЕНИЯ БЕЗОПАСНОСТИ ДВИЖЕНИЯ НА АВТОМОБИЛЬНЫХ ДОРОГАХ

The article discusses the main aspects of managing the condition of road pavements, as a key factor influencing the safety of traffic on roads, and notes the importance of studying the performance and predicting the service life of road structures. The article shows the need to conduct research to quantify the intensity of changes in transport and operational indicators and factors affecting the condition of road structures, traffic safety, and analyzes the main groups of methods and systems used to manage the condition of road pavements. Currently, there is a need for research aimed at assessing the performance of road structures in order to effectively evaluate design decisions, construction quality and ongoing activities to improve traffic safety as part of the maintenance and repair of roads.

WEIGHTED MATRIX INDEX: A TOOL TO DECODE THE INTERCONNECTEDNESS OF SOCIO-CULTURAL EXPRESSIONS, URBAN CONTEXT AND BUILT ENVIRONMENT

The ever-changing nature of our urban fabric reflects the complex cultural and socio – economic environment we live in. Globalization has brought with it a shift in the way we view our cities, from traditional urban forms that consider the wisdom and skills of our ancestors to analytical diagrams largely used to facilitate urban development. While this has resulted in a more efficient and convenient urban environment, it has also led to an insensitive and unresponsive urban fabric. Fortunately, there are examples of urban forms that have managed to preserve their significance over a long period of time, while still being adapted to the changing cultural and socio – economic contexts. These examples prove that it is possible to create places that are both timeless and responsive to the needs of the present and serve as inspirations for cities of the future. The purpose of this research study is to examine the role of design in shaping the continuity and change of urban fabric. Specifically, this paper investigates the relationship between contextual factors and design decisions that contribute to the evolution of the built environment in urban areas set in unique contexts. Within this framework, this paper aims to intricately compare and contrast Rome and Bhutan as distinctive urban environments, each situated within its own unique settings. This research study has used an approach that combines analysis of development processes, observation notes, documentary reports, published literature, and studies of case examples to investigate the relationship between design decisions and the continual change in the urban fabric. This factor, in particular underpins the relationship between the built environment and socio-cultural expressions that inform contextually appropriate design. A tool (weighted index matrix) for deciphering the interconnectedness between socio-cultural expressions, urban settings, and built environments was developed as a result of the research study. Further, the matrix index has been applied for the two select case examples and the results have been evaluated and analyzed.

Divide and recombine approach for warranty database: estimating the reliability of an automobile component

The continuously updated database of failures and censored data of numerous products has become large, and on some covariates, information regarding the failure times is missing in the database. As the dataset is large and has missing information, the analysis tasks become complicated and a long time is required to execute the programming codes. In such situations, the divide and recombine (D&R) approach, which has a practical computational performance for big data analysis, can be applied. In this study, the D&R approach was applied to analyze the real field data of an automobile component with incomplete information on covariates using the Weibull regression model. Model parameters were estimated using the expectation maximization algorithm. The results of the data analysis and simulation demonstrated that the D&R approach is applicable for analyzing such datasets. Further, the percentiles and reliability functions of the distribution under different covariate conditions were estimated to evaluate the component performance of these covariates. The findings of this study have managerial implications regarding design decisions, safety, and reliability of automobile components.

“Who Said That?” Applying the Situation Awareness Global Assessment Technique to Social Telepresence

As with all remotely controlled robots, successful teleoperation of social and telepresence robots relies greatly on operator situation awareness; however, existing situation awareness measurements, most being originally created for military purposes, are not adapted to the context of social interaction. We propose an objective technique for telepresence evaluation based on the widely accepted Situation Awareness Global Assessment Technique, adjusted to suit social contexts. This was trialled in a between-subjects participant study ( n = 56) comparing the effect of mono and spatial (binaural) audio feedback on operator situation awareness during robot teleoperation in a simulated social telepresence scenario. Subjective data were also recorded, including questions adapted from Witmer and Singer’s Presence Questionnaire, as well as qualitative feedback from participants. No significant differences in situation awareness measurements were detected; however, correlations observed between measures call for further research. This study and its findings are a potential starting point for the development of social situation awareness assessment techniques, which can inform future social and telepresence robot design decisions.

Reactions to asynchronous video interviews: The role of design decisions and applicant age and gender

AbstractAsynchronous video interviews (AVIs) are a form of one‐way, technology‐mediated selection interview that can help streamline and increase flexibility in the hiring process and are used to hire millions of applicants per year. Although applicant reactions to AVIs in general tend to be more negative than with traditional interview modalities, AVIs can differ widely in how they are designed. For instance, applicants can be provided with more or less preparation time, response length, rerecording options, or rely on different question formats. This study examines how AVI design features impact applicant reactions, as well as the moderating role played by applicant age and gender. Data from 27,809 real job applicant's AVI experiences were collected in 11 countries (69.3% English‐speaking) from 33 companies and relating to 72 types of positions. Data were fitted with linear mixed‐effects models to account for nesting. Results showed that allowing more preparation time and offering the opportunity to rerecord responses were related to more favorable reactions, while including more questions was related to more negative reactions. Applicants above the age of 31 reacted especially negatively to AVIs with more questions while those below the age of 30 preferred being allocated longer maximum response lengths. Women reacted more positively to increased preparation time. These findings might help both AVI vendors and hiring organizations design AVIs that facilitate a positive applicant experience. Our research also expands knowledge on applicant reactions to interviews, highlights crucial differences from traditional formats, and calls for integrating applicant characteristics into current theoretical frameworks on applicant reactions to AVIs.

Impact of epistemic uncertainty on tradeoff in model-based decision support for methane hydrate development system design

Global decarbonization trends encouraged the consideration of a methane hydrate (MH) development system design combined with carbon capture and storage (CCS) in the Japanese national MH research program. Previous studies have also proposed decarbonized MH development systems, but the conclusions vary due to epistemic uncertainty. Epistemic uncertainty arises from the knowledge and understanding of the subject, and each expert has different assumptions. Therefore, we assume that developing a model encompassing epistemic uncertainty as a platform allows for discussion toward system design decisions. This study builds the evaluation model, considering epistemic uncertainty to support the decision-making on the system design and reveal the tradeoff. It identifies the epistemic uncertainty affecting the tradeoff by changing the conditions based on previous studies. The evaluation model consists of technological options as modules, and all system concepts are evaluated by combining them. Epistemic uncertainty was subdivided and implemented within the evaluation model. As a result, the evaluation model output the tradeoff with bands of uncertainty. While the development field significantly impacts the results, hydrogen-related systems and offshore power plant systems score well owing to synergies between options. The epistemic uncertainty analysis regarding the tradeoff suggests that system design uncertainty impacts the conclusions. This finding indicates the importance of the model development as a platform for the evaluation of various system designs. This study contributed to an approach to model-based decision-making with epistemic uncertainty.

AutoMLBench: A comprehensive experimental evaluation of automated machine learning frameworks

With the booming demand for machine learning applications, it has been recognized that the number of knowledgeable data scientists cannot scale with the growing data volumes and application needs in our digital world. In response to this demand, several automated machine learning (AutoML) frameworks have been developed to fill the gap of human expertise by automating the process of building machine learning pipelines. Each framework comes with different heuristics-based design decisions. In this study, we present a comprehensive evaluation and comparison of the performance characteristics of six popular AutoML frameworks, namely, AutoWeka, AutoSKlearn, TPOT, Recipe, ATM and SmartML across 100 data sets from established AutoML benchmark suites. Our experimental evaluation considers different aspects for its comparison, including the performance impact of several design decisions, including time budget, size of search space, meta-learning, and ensemble construction. The results of our study reveal various interesting insights that can significantly guide and impact the design of AutoML frameworks.

Технологии информационного моделирования для обеспечения производственной безопасности и снижения уровня травматизма в строительстве

Abstract. The construction industry has one of the highest levels of occupational injuries. Despite the fact that most of the incidents occur due to systematic violations of occupational health and safety, many of them could have been prevented by assessing the risks of such traumatic situations at the design stage. Given the multifactorial nature of the building construction process, it is impossible to solve the problem without the use of information modeling technologies — to fundamentally reduce the risk of industrial injuries in the construction industry at the design stage. Currently, BIM technologies have become the most widespread. However, the proposed software solutions do not always include blocks for assessing the consequences of work from the point of view of safety, taking into account occupational injuries when making certain design decisions. This article discusses the issues of occupational safety at construction sites, conducted a statistical analysis of occupational injuries in the construction industry and developed recommendations for the use of modern information modeling technologies to increase the level of personnel protection and assess the risks of traumatic situations at the stages of construction of buildings.

Demystifying the QoS and QoE of Edge-hosted Video Streaming Applications in the Wild with SNESet

Video streaming applications (VSAs) are increasingly being deployed on large-scale edge platforms, which have the potential to significantly improve the quality of service (QoS) and end-user experience (QoE), ultimately maximizing business outcomes. However, there is currently very little understanding of how QoS, QoE, and the impact of QoS on QoE for VSAs on edge platforms in the wild and at scale. To close the knowledge gap, we collect SNESet, an active measurement dataset comprising QoS and QoE telemetry metrics of 8 VSAs over four months, covering end-users from 798 edge sites,30 cities, and 3 ISPs in one country.We characterize and compare the QoS and QoE metrics in SNESet with existing publicly available datasets, highlighting that SNESet includes a significantly greater number of metrics (horizontal diversity and vertical hierarchy) and provides more comprehensive coverage of specific metrics.Moreover, we qualitatively and quantitatively analyze the impact of QoS on QoE in both domain-general and domain-specific scenarios. Our findings can inform the system design decisions that different entities in the video ecosystem (content providers, video player designers, third-party optimizers, edge vendors) make to maximize end-users experience and ultimately maximize the business outcomes. We hope SNESet can attract more research efforts in the data management community, computer network community, and beyond.