System Designers Research Articles

Mechanisms to support changeability during sustainment: Modularity, excess, and operations

AbstractComplex engineered systems face protracted design cycles and indefinite lifetimes, leading to discrepancies between expected and actual operating conditions. The field of design for changeability has focused on developing strategies to cope with these discrepancies. Literature has implicitly assumed that future changes can be predicted by system designers, but this assumption does not match observed reality. Often, systems must be modified in unexpected ways to maintain value, limiting the usefulness of standard change mechanisms. To understand how unexpected changes are implemented in practice, we studied the C‐130, a setting where one platform performed many missions, and close air support in Desert Storm, a setting where many platforms performed one mission. Through this examination, we find that excess and operator change are key mechanisms for changeability that have been largely ignored by literature. Excess can enable additions to systems without having to remove or swap subsystems out. It is also a critical enabler of modular changes during the operational phase. Operator changes are non‐form changes driven by system users who change how their systems are used to gain new capabilities rather than relying on changes to the form of the system. This paper also studies the relationship between these mechanisms to shed light on how changeability is achieved in practice, building the foundation for future work to study tradeoffs of implementing valuable excess during design.

Integrating Equity in Public Sector Data-Driven Decision Making: Exploring the Desired Futures of Underserved Stakeholders

Public sector agencies aim to innovate not just for efficiency but also to enhance equity. Despite the growing adoption of data-driven decision-making systems in the public sector, efforts to integrate equity as a primary goal often fall short. This typically arises from inadequate early-stage involvement of underserved stakeholders and prevalent misunderstandings concerning the authentic meaning of equity from these stakeholders' perspectives. Our research seeks to address this gap by actively involving undersevered stakeholders in the process of envisioning the integration of equity within public sector data-driven decisions, particularly in the context of a building department in a Northeastern mid-sized U.S. city. Applying a speed dating method with storyboards, we explore diverse equity-centric futures within the realm of local business development, a domain where small businesses, particularly women-and minority-owned businesses, historically confront inequitable distribution of public services. We explored three essential aspects of equity: monitoring equity, resource allocation prioritization, as well as information and equity. Our findings illuminate the complexities of integrating equity into data-driven decisions, offering nuanced insights about the needs of stakeholders. We found that attempts to monitor and incorporate equity goals into public sector decision-making can unexpectedly backfire, inadvertently sparking community apprehension and potentially exacerbating existing inequities. Small business owners, including those identifying as women-and minority-owned, advocated against the use of demographic-based data in equity-focused data-driven decision-making in the public sector, instead emphasizing factors such as community needs, application complexity, and uncertainties inherent in small businesses. Drawing from these insights, we propose design implications to assist designers of public sector data-driven decision-making systems to better accommodate equity considerations.

Definitions of Fairness Differ Across Socioeconomic Groups & Shape Perceptions of Algorithmic Decisions

Understanding how people perceive algorithmic decision-making is remains critical, as these systems are increasingly integrated into areas such as education, healthcare, and criminal justice. These perceptions can shape trust in, compliance with, and the perceived legitimacy of automated systems. Focusing on San Francisco's decade-long policy of algorithmic school assignments, we draw on procedural and distributive justice theory to investigate parents' fairness perceptions of San Francisco's school assignment system. We find that key differences in parents' definitions of fairness shape their preferences for what constitutes a fair school assignment system, while also controlling for parents' school assignment outcomes. Moreover, parents' definitions and perceptions of fairness differ across socioeconomic and racial groups. For instance, among white respondents, the most used definition of fairness was "proximity'' to their assigned school, whereas, among Hispanic or Latino parents, the most popular definition of fairness was that the "same rules'' are applied to everyone. It is crucial for computational system designers and policymakers to consider these differences when deciding on the goals and values embedded in decision-making systems and who those goals and values reflect.

Cell Temperature Determination based on IEC61215: Solar Photovoltaic Experimental Study of Tropical Malaysia

Most commercial photovoltaic (PV) module data sheets include Nominal Operating Cell Temperature (NOCT) values, which assist PV system designers in estimating module temperatures under real outdoor conditions. However, the typical NOCT values of 45°C to 47°C do not account for tropical climates. This study seeks to develop an adjusted NOCT mathematical model and determine revised NOCT values suited for tropical conditions. The new proposed NOCT model follows the international standard IEC61215 but incorporates updated tropical Standard Reference Environment (SRE) parameters: solar irradiance (SI) of 800 W/m², ambient temperature (AT) of 31°C, and wind speed (WS) of 1 m/s. This modified NOCT model demonstrates improved accuracy over the existing model, with an average reduction of 2% in percentage error, root mean square error, and mean average percentage error. Outdoor NOCT testing conducted in Shah Alam, Malaysia, uncovered much higher NOCT values for various PV modules technology: 55°C for monocrystalline, 57°C for polycrystalline, and 59°C for thin film. These results emphasize the inadequacy of current NOCT values in commercial PV module data sheets, which do not accurately reflect conditions in tropical climates. The revised NOCT values from this study offer crucial thermal reference data for PV system designers, integrators, and researchers working in tropical regions, particularly Malaysia.

Effectiveness of EHR systems on decision support in primary healthcare: a technology acceptance model 3 perspective.

This study aims to evaluate healthcare practitioners' perceptions of electronic health record (EHR) systems and their effectiveness in supporting clinical decision-making in Tanzanian Primary Healthcare (PHC) facilities. A mixed-methods approach was employed, combining quantitative data from structured questionnaires and qualitative insights from open-ended responses. The study was conducted in the Dodoma region of Tanzania, focusing on a diverse representation of PHC facilities, including district hospitals, health centres and dispensaries. Data were analysed using multiple linear regression for quantitative data, and thematic analysis was applied to qualitative responses. The results revealed that while EHR systems are widely used in Tanzanian PHC facilities, their impact on clinical decision-making remains limited. Only a moderate portion of practitioners perceived EHR systems as effective in decision support, and frequent system use was negatively correlated with user satisfaction. Challenges such as inadequate training and support, system crashes, slow performance and poor usability and integration into clinical workflows were significant barriers to effectively utilising EHR systems. This study contributes to the limited literature on EHR system implementation in low-resource settings, specifically Tanzania, by focusing on decision-support features within EHR systems. The findings offer valuable insights for healthcare policymakers, system designers and practitioners to optimise EHR implementation and improve healthcare outcomes in resource-constrained environments.

Data Stream Protocols for Real-Time Messaging : Optimizing Performance and Reliability

This article explores the design and implementation of data stream protocols for real-time messaging, focusing on key aspects that contribute to their performance and reliability. It examines protocol architectures, data formatting and serialization techniques, error handling mechanisms, and quality of service features. The article compares popular protocols such as WebSocket and MQTT, discusses performance optimization techniques, and addresses security considerations. Emerging trends like WebTransport, HTTP/3, and edge computing integration are also explored, highlighting their potential to reshape the landscape of real-time messaging. By providing a comprehensive overview of current practices and future directions, this article aims to equip developers and system architects with the knowledge needed to design efficient and reliable real-time communication systems.

Evaluating the impacts of printing operations on indoor air quality in a printing press

PurposeBuilding operations and human activities indoors continuously affect air quality, contaminating the air and sometimes exceeding permissible limits which can be health threatening either in the short or long time. This implies a need for strict awareness and compliance with air quality standards, particularly in workplaces prone to air contaminants emissions. This study aims to evaluate printing-related pollutant concentrations and their effects on indoor air quality (IAQ). The study investigated a printing press's total volatile organic compounds (TVOC), particulate matter (PM), carbon monoxide and carbon dioxide emissions.Design/methodology/approachThis study used mainly an experimental research design supported by physical assessment by identifying the major printing-related pollutants, assessing the existing situation and measuring pollutant concentration levels using literature reviews, walkthrough inspections and experiments, respectively. The measurements were conducted in two scenarios: with and without printing activities, and the results were compared with relevant standards and guidelines.FindingsThe outcomes indicate that TVOC concentration reaches 120 ppb during printing and binding activities, exceeding the 75 ppb acceptable limit based on the time-weighted average. The PM2.5 concentrations reach 49 µg/m3 and PM10 up to 150 µg/m3, exceeding acceptable levels given by the US Environmental Protection Agency (EPA), which are 35 µg/m3 and 150 µg/m3 for PM2.5 and PM10, respectively. These high concentrations of TVOC and PM indicate a significant risk to the health of building occupants, particularly those with respiratory conditions. PM concentrations do not exceed permissible levels when no printing or bookbinding occurs, suggesting that printing-related activities can contribute to elevated TVOC and PM concentrations.Social implicationsThe social implication of the study lies in its ability to promote awareness among workers and improve their well-being which in turn relates to productivity. The study outcome could also encourage businesses to adopt more responsible environmental and social practices as part of corporate social responsibility practices.Originality/valueThe study's findings, which highlight the need for improved ventilation in printing halls, have the potential to significantly benefit building system designers, facility managers, policymakers and decision-makers. By providing information and theoretical support, the research can help integrate policies that regulate IAQ by reducing pollutant concentrations. This protects workers' health and helps update and enforce stricter IAQ regulations for industrial operations.

SIRE: Catalyst for Improvements in Accounting and Tax Processes

The Integrated Electronic Registration Systems have had a positive impact on the accounting and tax processes of SMEs. The article explored the impact of the Integrated Electronic Registration Systems| (SIRE, from the Spanish initials) on the accounting processes of SMEs in Peru, comparing it with practices in Ecuador and Colombia. For this purpose, 60 professionals participated in the study, which used a quantitative approach and the application of a survey and document analysis. The results of the study were analyzed quantitatively and qualitatively, thus examining how digitalization affects the efficiency and accuracy of accounting and tax processes. In terms of correlation results, there is a 63.10% correlation between SIRE and the accounting processes, while there is a 56% correlation between digital transformation and the accounting processes. Key lessons for policy makers and system designers were identified, emphasizing future reforms to facilitate an effective digital transition. This paper contributes to understanding how digitalization improves the economic performance and tax compliance of SMEs, providing a basis for future research and strategies aimed at integrating these companies into the digital economy.

Virtual reality-enabled high-performance emotion estimation with the most significant channel pairs

Human-computer interface (HCI) and electroencephalogram (EEG) signals are widely used in user experience (UX) interface designs to provide immersive interactions with the user. In the context of UX, EEG signals can be used within a metaverse system to assess user engagement, attention, emotional responses, or mental workload. By analyzing EEG signals, system designers can tailor the virtual environment, content, or interactions in real time to optimize UX, improve immersion, and personalize interactions. However, in this case, in addition to the signals' processing cost and classification accuracy, cybersickness in Virtual Reality (VR) systems needs to be resolved. At this point, channel selection methods can perform better for HCI and UX applications by reducing noisy and redundant information in generally unrelated EEG channels. For this purpose, a new method for EEG channel selection based on phase-locking value (PLV) analysis is proposed. We hypothesized that there are interactions between EEG channels in terms of PLV in repeated tasks in different trials of the emotion estimation experiment. Subsequently, frequency-based features were extracted. The features were classified by dividing them into bags using the Multiple-Instance Learning (MIL) variant. This study provides higher classification performance using fewer EEG channels for emotion prediction. The performance rate obtained in binary classification with the Random Forests (RF) algorithm is at a promising level of 99%. The proposed method achieved an accuracy of 99.38% for valence using all channels on the new dataset (VREMO) and 98.13% with channel selection. The benchmark dataset (DEAP) achieved accuracies of 98.16% using all channels and 98.13% with selected channels.

Security Considerations for Large Language Model Use: Implementation Research in Securing LLM-Integrated Applications

Large Language Models (LLMs) are rapidly being adopted in various applications due to their natural language capabilities that enable user interaction using human language. As system designers, developers, and users embrace generative artificial intelligence and large language models in various applications, they need to understand the significant security risks associated with them. The paper describes a typical LLM-integrated application architecture and identifies multiple security risks to address while building these applications. In addition, the paper provides guidance on potential mitigations to consider in this rapidly evolving space to help protect systems and users from potential attack vectors. This paper presents the common real-world application patterns of LLMs trending today. It also provides a background on generative artificial intelligence and related fields.

Systematic Survey Analysis of the Application of Artificial Intelligence Base Network on Grid Computing Techniques

A smart grid is a contemporary electrical system that supports two-way communication and utilizes the concept of demand response. In order to increase the smart grid's dependability and enhance the consistency, efficiency, and efficiency of the electrical supply, stability prediction is required. The true test for smart grid system designers and specialists will therefore be the increase of renewable energy. With the goal of integrating the electric utility infrastructure into the advanced communication era of today, both in terms of function and architecture, this program has achieved great strides toward modernizing and expanding it. In this study, researchers used the Systematic literature review method which identifies, evaluates and interprets all relevant research results related to certain research questions, certain topics, or phenomena of concern. The study review on how a smart grid applied different deep learning techniques and how renewable energy can be integrated into a system where grid control is essential for energy management. The article discusses the idea of a smart grid and how reliable it is when renewable energy sources are present. Globally, a change in electric energy is needed to reduce greenhouse gas emissions, prevent global warming, reduce pollution, and boost energy security.

A Systematic Survey on the Application of Artificial Intelligence (ai) Baseline Networks on Grid Computing Techniques - Challenges, Novelty and Prospects

A smart grid is a contemporary electrical system that supports two-way communication and utilizes the concept of demand response. To increase the smart grid's dependability and enhance the consistency, efficiency, and efficiency of the electrical supply, stability prediction is required. The true test for smart grid system designers and specialists will therefore be the increase of renewable energy. To integrate the electric utility infrastructure into the advanced communication era of today, both in terms of function and architecture, this program has made great strides toward modernizing and expanding it. The study reviews how a smart grid applied different deep learning techniques and how renewable energy can be integrated into a system where grid control is essential for energy management. The article discusses the idea of a smart grid and how reliable it is when renewable energy sources are present. Globally, a change in electric energy is needed to reduce greenhouse gas emissions, prevent global warming, reduce pollution, and boost energy security.

How Does Aesthetic Design Affect Continuance Intention in In-Vehicle Infotainment Systems? An Exploratory Study

With the digitalization of automobile cabins, in-vehicle infotainment systems play an increasingly pivotal role in vehicles. This study aims to understand how the interface aesthetics of the in-vehicle infotainment system affect users’ continuance intention in in-vehicle infotainment systems. Based on a literature review, a theoretical model was constructed, encompassing seven latent variables: simplicity, colorfulness, diversity, craftsmanship, functional value, emotional value, and continuance intention. Analysis of 243 valid questionnaires revealed that both functional and emotional values serve as crucial mediators in encouraging users to continue using the in-vehicle infotainment system, with functional quality being the core element. Moreover, simplicity, diversity, and craftsmanship indirectly affect continuance intention by influencing both functional and emotional values. These findings underscore the need for future designers of in-vehicle infotainment systems to focus on interface functionality and emotional needs, and to ensure that content is concise, engaging, user-friendly, and visually polished, thereby enhancing the user experience and fostering the intention to continue usage.

A Design Proposal Using Coherently Radiating Periodic Structures (CORPSs) for 2-D Phased Arrays of Limited Scanning

New configurations of 2-D phased arrays are proposed in this paper for reducing the number of phase shifters. This design methodology is based on the use of a novel coherently radiating periodic structures (CORPSs) block for 2-D phased arrays. Two new antenna systems for 2-D phased arrays are studied and analyzed utilizing the CORPSs blocks of four inputs and nine outputs. These CORPSs feeding blocks are applied in a smart way to feed the planar antenna arrays by generating the required phase plane and reducing the number of control ports. Interesting results are provided based on the experimental measurements and full-wave simulations. These results illustrate a great reduction of the active devices (phase shifters), providing a good design compromise in terms of the scanning range and side lobe level performance. Furthermore, the provided results illustrate a maximum reduction capability in the number of phase shifters of 81%, considering a scanning range of ±30° in azimuth and ±30° in elevation. A raised cosine distribution is applied to reach side lobe levels of −19 dB for ±18° and −17 dB for ±30° in elevation. These benefits could be of interest to designers of phased antenna systems.

Centralization potential of automotive E/E architectures

Current automotive E/E architectures are subject to significant transformations: Computing-power-intensive advanced driver-assistance systems, bandwidth-hungry infotainment systems, the connection of the vehicle with the internet and the consequential need for cyber-security drives the centralization of E/E architectures. A centralized architecture is often seen as a key enabler to master those challenges. Available research focuses mostly on the different types of E/E architectures and contrasts their advantages and disadvantages. There is a research gap on guidelines for system designers and function developers to analyze the potential of their systems for centralization. The present paper aims to quantify centralization potential reviewing relevant literature and conducting qualitative interviews with industry practitioners. In literature, we identified seven key automotive system properties reaching limitations in current automotive architectures: busload, functional safety, computing power, feature dependencies, development and maintenance costs, error rate, modularity and flexibility. These properties serve as quantitative evaluation criteria to estimate whether centralization would enhance overall system performance. In the interviews, we have validated centralization and its fundament – the conceptual systems engineering – as capabilities to mitigate these limitations. By focusing on practical insights and lessons learned, this research provides system designers with actionable guidance to optimize their systems, addressing the outlined challenges while avoiding monolithic architecture. This paper bridges the gap between theoretical research and practical application, offering valuable takeaways for practitioners.

Academician V. H. Serheiev – Control System Designer, Founder of the Scientific and Design School, Honored Citizen of Kharkiv (on His 110th Birthday)

March 5, 2024 marks the 110th birthday of Volodymyr Hryhorovych Serheiev, an outstanding scientist, chief designer of control systems for strategic combat missiles, launch vehicles, spacecraft and transport modules of orbital complexes, Academician of the National Academy of Sciences of Ukraine and an Honored Citizen of Kharkiv. Despite his significant scientific achievements in the field of rocket and space engineering, the silhouette of V. H. Serheiev is hardly reflected in the modern history of science. Based on representative sources, the article highlights the main achievements of the scientist in the field of dynamics of automatic control systems and the design of rocket and space engineering control systems. The summary of the most prominent space projects is based on the memories of witnesses and direct participants. The personal qualities of V. H. Serheiev as the head of the Special Design Office No. 692 are noted. The historical retrospective describes technical developments and inventions meant to improve the control systems of intercontinental ballistic missiles R-16, R-16У, R-36, R-36П, R-36 orbital, R-36М, R-36М UTTH, UR-100N, UR-100HU, and R-36М2. At the initiative of V. H. Serheiev, complex stands were developed, which worked non-stop in all modes of operation of the necessary equipment and solved complex scientific and technical problems of creating an on-board digital computer. V. H. Serheiev was the chief control system designer of space launch vehicles Kosmos, Kosmos-2, Cyclone-2, and Cyclone-3 and Tselina series spacecraft. The article features innovative solutions implemented under Serheiev’s leadership during the creation of the Energia launch vehicle, supply vehicles of the Almaz space rocket system and target orbital modules of the Saliut and Myr space stations, and international launch vehicles Dnipro, Rokit and Strila. The article considers the issues of V. H. Serheiev’s direct participation in the organization of the training system for scientific personnel in the relevant specialties at Ukraine’s higher education institutions, as well as the development of international cooperation. It is substantiated that the scientist created one of the leading science and construction schools for the development of control systems for rocket and space technology, which is internationally recognized. The authors emphasize that V. H. Serheiev devoted a lot of attention to people. At his initiative and with his support, a district named after the founder of aerodynamics, M. Y. Zhukovskyi, was created in Kharkiv for the employees of “Hartron” enterprise. The district was not far from the enterprise and had a well-developed infrastructure, such as kindergartens, schools, shops, a swimming pool and a complex of residential buildings.

Human factors methods in the design of digital decision support systems for population health: a scoping review

BackgroundWhile Human Factors (HF) methods have been applied to the design of decision support systems (DSS) to aid clinical decision-making, the role of HF to improve decision-support for population health outcomes is less understood. We sought to comprehensively understand how HF methods have been used in designing digital population health DSS.Materials and methodsWe searched English documents published in health sciences and engineering databases (Medline, Embase, PsychINFO, Scopus, Comendex, Inspec, IEEE Xplore) between January 1990 and September 2023 describing the development, validation or application of HF principles to decision support tools in population health.ResultsWe identified 21,581 unique records and included 153 studies for data extraction and synthesis. We included research articles that had a target end-user in population health and that used HF. HF methods were applied throughout the design lifecycle. Users were engaged early in the design lifecycle in the needs assessment and requirements gathering phase and design and prototyping phase with qualitative methods such as interviews. In later stages in the lifecycle, during user testing and evaluation, and post deployment evaluation, quantitative methods were more frequently used. However, only three studies used an experimental framework or conducted A/B testing.ConclusionsWhile HF have been applied in a variety of contexts in the design of data-driven DSSs for population health, few have used Human Factors to its full potential. We offer recommendations for how HF can be leveraged throughout the design lifecycle. Most crucially, system designers should engage with users early on and throughout the design process. Our findings can support stakeholders to further empower public health systems.

Formal Modelling and Model Checking of a Flood Monitoring and Rescue System: A Case Study of Safety-Critical System

The flood incidents are becoming more often and severe, thus extreme events require efficient and effective means of controlling and saving lives and property. The reason for this paper is to use Formal Modelling and Model Checking to analyse a new safety critical Flood Monitoring and Rescue System (FMRS) that shall form the basis for the efficient response to floods. Employing the TLA+ analysis, which outlines the FMRS’s dynamic behavior and operational specifications comprehensively. It is important to stress that in our work we address one of the most exciting directions of applying formal methods for the first time in collaboration with real-world safety-critical system designers and offer a powerful and transparent systematic approach to verifying safety-critical systems’ correctness, safety, and reliability. The TLA+ specifications are very carefully designed to represent multiple aspects of the FMRS, such as sensor systems, communication interfaces, as well as the rescue activity itself. To this end, we use model checking methodologies in order to assess the system’s compliance with the required safety properties, including timely detection of floods, correct delivery of data, and synchronization of rescue operations. The performed model checking demonstrates the presence of essential information about the system’s potential failure and weaknesses, which can be used for FMRS architecture improvement and development. Thus, this case shows that the best use of formal methods exist not as ad hoc methods for resolving some issues in the development of safety-critical systems, but a structured template that could be applied in other domains where high degree of assurance in the reliability of a system is needed. Besides the novel method for the better future of the field of formal verification, the proposal also sketches functional relevance of integrating the effective and efficient approaches for monitoring floods and emergency rescue operations in real-world contexts.

Integration of the Functional Hazard Assessment Within a Model-Based Systems Engineering Framework

A major challenge in developing novel aircraft concepts is demonstrating the safety of increasingly complex and multifunctional aircraft systems. Aircraft manufacturers are adopting model-based systems engineering approaches to develop these new aircraft. The safety assessment process follows suit with model-based safety assessment. However, system and safety engineers still transfer information that is mainly document-based during the system architecting process. This paper aims to improve this process. First, a framework for developing system architecture specification models is introduced using the Architecture Analysis and Design Integrated Approach (ARCADIA)/Capella methodology and tool, illustrated with an aircraft landing gear braking system. Secondly, the paper proposes enhancements to the system specification model to enable functional hazard assessment and to capture the results within the system architecture specification model, i.e., using color-coding of system functions according to the severity of their associated failures as a visual aid to the system architect. In addition, the proposed features in the system specification model can help the safety engineer analyze failure relationships better. In summary, the proposed method improves consistency between the system architect and the safety expert in making safety-informed architecting decisions early in the development process, improving its effectiveness.

Multidisciplinary Reliability Design Optimization Modeling Based on SysML

Model-Based Systems Engineering (MBSE) supports the system-level design of complex products effectively. Currently, system design and optimization for complex products are two distinct processes that must be executed using different software or platforms, involving intricate data conversion processes. Applying multidisciplinary optimization to validate system optimization often necessitates remodeling the optimization objects, which is time-consuming, labor-intensive, and highly error-prone. A critical activity in systems engineering is identifying the optimal design solution for the entire system. Multidisciplinary Design Optimization (MDO) and reliability analysis are essential methods for achieving this. This paper proposes a SysML-based multidisciplinary reliability design optimization modeling method. First, by analyzing the definitions and mathematical models of multidisciplinary reliability design optimization, the SysML extension mechanism is employed to represent the optimization model based on SysML. Next, model transformation techniques are used to convert the SysML optimization model generated in the first stage into an XML description model readable by optimization solvers. Finally, the proposed method’s effectiveness is validated through an engineering case study of an in-vehicle environmental control integration system. The results demonstrate that this method fully utilizes SysML to express MDO problems, enhancing the efficiency of design optimization for complex systems. Engineers and system designers working on complex, multidisciplinary projects can particularly benefit from these advancements, as they simplify the integration of design and optimization processes, facilitating more reliable and efficient product development.