Design Flaws Research Articles

Mining LDA topics on construction engineering change risks based on graded evidence.

Engineering change (EC) risk may negatively impact project schedule, cost, quality, and stakeholder satisfaction. However, existing methods for managing EC risk have certain shortcomings in evidence selection and do not adequately consider the quality and reliability of evidence associated with EC risks. Evidence grading plays a crucial role in ensuring the reliability of decisions related to EC risks and can provide essential scientific and reliability support for decision-making. In order to explore the potential risks associated with architectural engineering changes (ECs) and identify the most significant ones, this study proposed a methodology that combines evidence grading theory and Latent Dirichlet Allocation (LDA) topic analysis means. Initially, the evidence-based grading theory served as the creation of a grading table for evidence sources related to EC risk. Specifically, we categorized the evidence sources into three levels based on their credibility. Subsequently, we selected evidence with higher credibility levels for textual analysis, utilizing the LDA topic model. This involved analyzing regulations, industry standards, and judgment documents related to EC, ultimately identifying the themes associated with EC risks. In addition, by combining EC risk topics with relevant literature, we identified factors influencing EC risks. Subsequently, we designed an expert survey questionnaire to determine the key risks and important risk topics associated with potential risks. The results show that by synthesizing information from both Class A and B evidence, a total of five prominent risk themes were identified, namely contract, technology, funds, personnel, and other hazards. Among them, the technical risk has the highest value, so it implies that the risk is the most important, and the key risks are engineering design defects, errors, and omissions.

Is The Third Restatement of Design Defect A Defective Product?

Is The Third Restatement of Design Defect A Defective Product?

Occupational diseases occurring in acceptable working conditions: Causes and features of development in the Russian Arctic

Introduction: Acceptable working conditions are essential but they do not ensure complete prevention of occupational diseases. The purpose of the study was to establish possible causes and features of development of occupational diseases in blue-collar employees having acceptable working conditions. Materials and methods: Data on working conditions and occupational disease rates collected within public health monitoring and information from the Register of extracts from occupational disease records in the Russian Arctic for 2007–2021 were analyzed. The relative risk (RR) and 95 % confidence interval (95 % CI), the goodness-of-fit criterion (χ2) for the analysis of four-field tables, and the approximation criterion (R2) to determine the measure of correlation between values were calculated. Results: It has been established that 74 of 10,343 occupational disease cases (0.72 %) were registered at enterprises of the Russian Arctic with acceptable working conditions. They were more often related to chemical exposure (40.5 %) and increased labor severity (28.4 %) mainly attributed to equipment design defects (58.1 %) and imperfect technological processes (33.8 %). This group of workers was noted for a younger mean age (48.1 ± 1.3 years), shorter duration of employment (18.9 ± 1.5 years), and a larger proportion of women (28.6 %) compared to those exposed to harmful and hazardous working conditions. It included employees of such jobs as a lorry driver (27.0 %) and painter (10.8 %) from such types of economic activity as mining (56.8 %) and construction (14.9 %). Poisoning (n = 17), radiculopathy (n = 12), mono(poly)neuropathy (n = 11), and bronchial asthma (n = 8) were found to be the most prevalent occupational disorders in them. Conclusion: Some circumstances of registration of health disorders in workers with low exposure to occupational risk factors (usually below occupational safety standards) remain unclear. It is critical to establish validity of such a diagnosis, specifics of drawing up a report on a case of occupational disease, and reporting forms of the Russian Federal Service for Surveillance on Consumer Rights Protection and Human Wellbeing (Rospotrebnadzor) describing occupational hazards.

The effect of errors in structural system design on the structure damaged in 2023 Turkey earthquakes: A case study

On 6 February 2023, two large earthquakes of Mw 7.7 and 7.6 occurred in the Pazarcik and Elbistan districts of Kahramanmaras province in Turkey, causing extensive structural damage, collapsed buildings and casualties. This study examines a damaged building and presents the relevant repair and strengthening procedures. The importance of design flaws in the structural system, particularly when subjected to horizontal and vertical ground motions, on the performance of the structure is highlighted in this case study. The effects of the interrupted frames and components with unsuitable cross-sectional properties for load transfer within the structure were comprehensively assessed using 3D modelling and on-site investigations. Following repair and strengthening works to improve load transfer, the analysis carried out on the model showed a reduction in LS of approximately 33 % for beams and 45 % for columns.

ВІДНОВЛЕННЯ ОПОРНИХ ЧАСТИН ЗОВНІШНІХ СТІНОВИХ ПАНЕЛЕЙ СЕРІЇ ІІС-04-2 З ВРАХУВАННЯМ СЕЙСМІЧНИХ НАВАНТАЖЕНЬ РАЙОНУ 7 БАЛІВ

This paper presents the results of the study of the strength of the junctions of external wall panels and columns and crossbars and columns of the IIS-03-02 series, which was used in the construction of the building of the Faculty of Biology of the Uzhgorod State University in the city of Uzhhorod. The survey and research data, as well as the development of recommendations, which were carried out by the employees of the Physico-Mechanical Institute named after G.V. Karpenka of the National Academy of Sciences on the order of «Zakarpatzalizoboton» VO from July 19, 1991. The work describes basic information about the building, its design and construction. The main reasons that led to the need for research and development of recommendations for strengthening the junctions of panels and columns and crossbars and columns and strengthening their short consoles and support niches of panels are established. Also, the data on identified design errors, shortcomings and defects in the construction and manufacture and transportation of reinforced concrete structures are given. In particular, the own weight of panels and walls is significantly overestimated by up to 25%; in some panels, embedded parts are embedded in concrete and have deviations from the design position; also in some panels there is a deviation of up to 20-30 mm from flatness; sockets for supporting panels on the console of the columns are installed at different angles to the plane of the panel; size fluctuations between the axes of the columns in some places are higher than the norm up to 50-70 mm; poor-quality reinforcement of the panels in the places where the supporting parts of the panels rest on the short console of the column, etc. The verification calculation of the support table of the reinforcement of the column consoles and the supporting parts of the panels was performed. On the basis of field survey and relevant calculations, appropriate recommendations were developed for strengthening the joints of external wall panels and columns and crossbars and columns. In particular, the elimination of identified shortcomings and defects, ensuring the bearing capacity of short cantilevers of the IIS-04-02 series for seismic loads for the construction area of 7 points.

Rolling bearing fault diagnosis method using time-frequency information integration and multi-scale TransFusion network

Advances in deep learning methods have demonstrated remarkable development in diagnosing faults of rotating machinery. The currently popular deep neural networks suffer from design flaws in their network structure, leading to issues of long-term dependencies in fault diagnosis models built upon conventional deep neural networks. Consequently, such models exhibit insufficient global perceptual capabilities towards fault features. Furthermore, how accurately pre-trained models can diagnose faults is hugely impacted by changes in bearings’ working conditions. To tackle the aforementioned issues, this study puts forth a multi-scale TransFusion (MSTF) model for diagnosing faults in rolling bearings under multiple operating conditions. Firstly, a time-frequency symmetric dot pattern transformation technique is designed to transform the original vibration signals into two-dimensional representations. This method can effectively highlight the distinctions between different fault types. Secondly, a multi-scale feature fusion module is established, which fully extracts low-level features from the time-frequency signals and reduces the complexity of the subsequent attention calculations. Meanwhile, relying on the advantages of the Transformer model in capturing global dependencies, the long-range periodic fault information is deeply mined. Finally, multi-head and multi-layer attention are visualized to enhance the interpretability of the model. After analyzing two case studies with both public and experimental datasets, the examination demonstrated that the developed model outperformed other state-of-the-art models. The diagnostic model developed in this study exhibits the ability to accurately diagnose bearing faults across multiple operating conditions while maintaining high robustness to signals contaminated with noise.

Design displacement for lifelines at fault crossings: the code-based approach for Europe

The earthquake-resistant design of lifelines, such as pipelines, tunnels and bridges, is based on the reliable representation and estimation of the seismic loading. In the case of lifeline–fault crossings, the design fault displacement is typically derived from estimates based on fault dimensions via empirical fault scaling relations for a given “design” scenario event. This approach comes with an unknown level of safety because the fault productivity and the actual distribution of earthquake events are essentially disregarded. To overcome this challenge, a simplified approach is proposed by statistically analyzing the outcome of probabilistic fault displacement hazard analyses (PFDHAs). A selection of faults from the 2020 European Fault-Source Model is used to build the logic tree and to set the range of parameters considered in the PFDHAs. The methodology allows the (mostly conservative) approximation of the fault displacement corresponding to any given return period based on readily available data, namely fault productivity, fault mechanism, fault length, and lifeline crossing location on the fault. The proposed methodology has been proposed and adopted as an informative Annex in prEN 1998-4:2022.

Development of a Prediction System for Design Defects of Buildings

The research aimed to establish a quantitative model to predict the occurrence of five types of design defects: unsafe design, incompatible design, inefficient design, design ambiguity, and design delays. It also examined the contractor's liability for design to determine who is ultimately responsible for design defects disputes between the employer and contractor. The study employed a descriptive methodology to identify fifteen potential influencing factors on design defects. Data were collected from 42 construction projects and tested using Design of Experiments (DOE). Out of these fifteen factors, only five—design schedule, design firm experience, stakeholders’ involvement, project delivery system, and information accuracy—had a significant impact on design defects. These factors were used in the development of a new model to predict the occurrence of design defects. The model was validated using data that was held separate from the model development process for validation purposes. The calculated Mean Absolute Percentage of Error (MAPE) for the new model is 19%, which is considered a "good" prediction accuracy. The research achieved three significant milestones: 1) It identified the ultimate responsibility for the consequences of design defects in construction projects across different jurisdictions. This information can be used to resolve potential disputes between employers, designers, and contractors’ organizations. 2) It provided guidelines on how to minimize design defects in construction projects, thereby mitigating the consequences of such defects. 3) It developed a new model to predict the occurrence of design defects in construction projects. This model aids decision-makers in responsible organizations during the process of predicting the appropriate reserve to be added to the project schedule and budget. Consequently, it helps mitigate the risk of design defect-related delays and cost overruns. Doi: 10.28991/CEJ-SP2023-09-017 Full Text: PDF

Product Design Defect Detection and Automatic Repair Algorithm Based on CAD and Machine Vision

Product Design Defect Detection and Automatic Repair Algorithm Based on CAD and Machine Vision

Building synthetic chromosomes from natural DNA

De novo chromosome synthesis is costly and time-consuming, limiting its use in research and biotechnology. Building synthetic chromosomes from natural components is an unexplored alternative with many potential applications. In this paper, we report CReATiNG (Cloning, Reprogramming, and Assembling Tiled Natural Genomic DNA), a method for constructing synthetic chromosomes from natural components in yeast. CReATiNG entails cloning segments of natural chromosomes and then programmably assembling them into synthetic chromosomes that can replace the native chromosomes in cells. We use CReATiNG to synthetically recombine chromosomes between strains and species, to modify chromosome structure, and to delete many linked, non-adjacent regions totaling 39% of a chromosome. The multiplex deletion experiment reveals that CReATiNG also enables recovery from flaws in synthetic chromosome design via recombination between a synthetic chromosome and its native counterpart. CReATiNG facilitates the application of chromosome synthesis to diverse biological problems.

Characterization changes and research waste in randomized controlled trials of global bariatric surgery over the past 20 years: cross-sectional study.

The results of several large randomized controlled trials (RCTs) have changed the clinical practice of bariatric surgery. However, the characteristics of global RCTs of bariatric surgery have not been reported internationally and whether there was research waste in these RCTs is unknown. Search ClinicalTrials.gov for bariatric surgery RCTs registered between January 2000 and December 2022 with the keywords 'Roux-en-Y gastric-bypass' and 'Sleeve Gastrectomy'. The above analysis was conducted in January 2023. A total of 326 RCTs were included in this study. The number of RCTs registered for sleeve gastrectomy and gastric bypass surgery increased year by year globally. Europe has always accounted for the largest proportion, Asia has gradually increased, and North America has decreased. A total of 171 RCTs were included in the analysis of waste, of which 74 (43.8%) were published. Of the 74 published RCTs, 37 (37/74, 50.0%) were judged to be adequately reported and 36 (36/74, 48.6%) were judged to have avoidable design defects. In the end, 143 RCTs (143/171, 83.6%) had at least one research waste. Body weight change as the primary endpoint (OR: 0.266, 95% CI: 0.103-0.687, P =0.006) and enrolment greater than 100 (OR: 0.349, 95% CI: 0.146-0.832, P =0.018) were independent protective factors for research waste. This study for the first time describes the characteristic changes of the mainstream RCT of bariatric surgery globally in the last 20 years and identifies a high research waste burden and predictive factor in this area, which provides reference evidence for carrying out bariatric surgery RCTs more rationally.

Implementation of the EU's CBAM under the WTO Rules: Process, Relations, Responses

The European Union (EU), a global leader in carbon reduction measures, formally adopted its proposed Carbon Border Adjustment Mechanism (CBAM) in April 2023. However, it may not comply with existing WTO rules due to its design flaw. Thus, it may be viewed as a new trade barrier, which may result serious legal issues and trade disputes regarding the compatibility of CBAM with the trade rules of the General Agreement on Tariffs and Trade (GATT) under the World Trade Organization (WTO). In practice, however, the adoption and implement of CBAM has not been prevented by these conflicts. Therefore, this article attempts to explore this contradiction and evaluate the impact of CBAM on WTO rules. Eventually, this article concludes that CBAM as an attempt to put forward environmentally friendly trade rules may promote updating WTO rules under international consensus of carbon reduction. The focus of this article will be discussed by providing a systematic review of the process and content of CBAM, examining the relationship between the CBAM and WTO rules and analysing the responses to CBAM of other countries.

What does it take to make a wrong decision? A qualitative study from Pakistan's health sector.

Pakistan's health system over the past three decades has experienced social, economic, geopolitical instability, and notwithstanding man-made and natural catastrophes. Since 2001, the health system in Pakistan has undergone three phases of organizational and management reforms and does not have a unified national health policy since then. The aim of this research was to assess the factors behind the decision-making by policy planners in the health system of Pakistan. An exploratory qualitative study based on grounded theory was designed where in-depth interviews conducted with 20 representatives of the political constituencies, civil bureaucracy, health planners and managers, research and educational institutions, NGOs providing technical support in the health sector, development partners and media. There leading reason cited was the dearth of leadership in health sector, which is compounded by a range of factors such as "institutional monopoly", "contextual deterrents", "power for turf"; "inadequate knowledge", and "design faults". Such factors were perceived to have a serious effect on the competencies, roles and responsibilities, use of knowledge for decision making. The behavioral aspects of decision makers include the "mindset," and "conflicting interests". The multitude of factors and complexities within the health sector of Pakistan continue to widen the vacuum in the leadership echelons. Hence, there is a high probability of taking wrong decisions not based on evidence, and resulting in a grossly under-performing health system.

Watertight insertion of heavy sliding doors in exterior walls

The joints around heavy terrace doors are considered a weak point in rain-exposed façades, as it is vulnerable to defects in design and construction. The insertion process of heavy sliding doors is a notable challenge. Design recommendations from manufacturers as well as national advisory agencies are currently lacking. This paper presents a full-scale laboratory study on the water tightness of heavy sliding doors with joints waterproofed according to five different solutions. The door assembly is mounted in a pressurized cabinet with water spray nozzles to simulate wind-driven rain. The interior side of the joint around the door is monitored for moisture leaks at steadily increasing pressure levels. It was found that leaks most often occur in the corners of the frame. Sealant mounted before the door itself was hoisted in place tended to be twisted or distorted as the door was adjusted in the frame, spoiling the waterproofing. A common feature of the most watertight solutions was that the sealant was mounted after the door itself was fastened to the frame. The sealant should be continuous, flexible, mounted in a single plane, and preferably be accessible during the assembly process. Waterproofing recommendations for the design and insertion of sliding doors should account for practical challenges brought on by the heavy weight.

Re-evaluation of the Cerebral Palsy’s orthotic need in Adaptive Seating Orthosis (ASO) design

Adaptive seating orthosis (ASO) for Cerebral Palsy (CP) patients in Malaysia mostly are imported, highly expensive for the bottom millions, bulky and complicated design structure, and not accommodating users’ preferences. Through a study involving 10 CP patients with their parents/guardians in Ma-laysia, the goal of this paper is to re-assess the design needs of CP’s orthotic in ASO design. The purpose of the study is to identify the difficulties, as well as the ergonomic and functional problems, in caring for CP patients with the current ASO. The result of the study revealed several of the problems that parents/guardians face while taking care of the CP patient, mainly caused by technical flaws in the current ASO design. Therefore, a few design criteria have been proposed to solve the addressed problems. The contribution of this study will help as a preference for the improvement and development of ASO design.

Distributed Adaptive Fault-Tolerant Control for Multiagent Systems via Virtual-Actuator-Based Reconfiguration.

This article aims to develop a virtual-actuator-based control scheme for the consensus tracking problem of multiagent systems (MASs) against actuator faults and mismatched disturbances. The proposed scheme has a double-layer structure. In the cyber layer, the nominal controller is designed with neighboring information for the fault-free case. While in the physical layer, the fault compensator, working as the virtual actuator, is applied to reconfigure faulty plants adaptively. This design enjoys the advantages that the nominal controller needs no adjustment and all its properties can be preserved after failure. Moreover, the proposed control scheme is distinguished by the following features: 1) the commonly imposed rank condition on outage faults is removed; 2) the norm bound of the leader's input is allowed to be unknown even though the topologies are switching and directed; and 3) there is no need to use the estimates of faults in the virtual actuator design, which means the negative impacts caused by the inaccurate fault estimation can be avoided. Finally, a numerical example is given to validate the effectiveness of the theoretical results.

Compendium of Measures to Prevent Disease Associated with Animals in Public Settings, 2023

Abstract Opportunities for the public to interact with animals in public settings such as petting zoos, fairs, and farm visits can be valuable learning and entertainment experiences. However, zoonotic disease transmission from healthy animals on exhibit and their environments, as well as injuries and other health problems, may result from these interactions if steps are not taken to minimize risks. The 2023 Compendium of Measures to Prevent Disease Associated with Animals in Public Settings provides background about these potential risks and updates recommendations for reducing those risks. Enteric zoonotic disease risks from animal contact in public settings include Shiga toxin–producing Escherichia coli infections, cryptosporidiosis, and campylobacteriosis. These infections occur when pathogens are accidentally ingested by individuals following direct contact with animals or contaminated objects. Zoonotic influenza infections can occur in a similar manner or through aerosols generated from infected animals. Other infectious diseases, parasitic infections, bites, and other injuries are also possible hazards in these settings. Inadequate handwashing and facility design flaws are frequent contributors to these risks, especially on farms or temporary exhibits not specifically designed for public use. Venues should provide sufficient handwashing stations and establish clearly defined animal contact areas. Operators should educate visitors about potential disease and injury risks, steps necessary to minimize exposure, and the importance of handwashing after the visit. Additionally, operators and visitors alike should realize that certain individuals are at heightened risk for zoonotic infections. Signs, handouts, and other educational materials are publicly available in a toolkit that accompanies the compendium.

Partial Network Partitioning

We present an extensive study focused on partial network partitioning. Partial network partitions disrupt the communication between some but not all nodes in a cluster. First, we conduct a comprehensive study of system failures caused by this fault in 13 popular systems. Our study reveals that the studied failures are catastrophic (e.g., lead to data loss), easily manifest, and are mainly due to design flaws. Our analysis identifies vulnerabilities in core systems mechanisms including scheduling, membership management, and ZooKeeper-based configuration management. Second, we dissect the design of nine popular systems and identify four principled approaches for tolerating partial partitions. Unfortunately, our analysis shows that implemented fault tolerance techniques are inadequate for modern systems; they either patch a particular mechanism or lead to a complete cluster shutdown, even when alternative network paths exist. Finally, our findings motivate us to build Nifty, a transparent communication layer that masks partial network partitions. Nifty builds an overlay between nodes to detour packets around partial partitions. Nifty provides an approach for applications to optimize their operation during a partial partition. We demonstrate the benefit of this approach through integrating Nifty with VoltDB, HDFS, and Kafka.

Mitigating Recordable Incidents in Nigeria's Oil & Gas Construction Industry: A Human Factor Engineering (HFE) Approach

The Nigerian Oil and Gas construction industry poses significant risks due to incident prevention limiting factors. These factors include inadequate resource allocation, prioritization of production over safety, poor communication, insufficient supervision, suboptimal workplace design, weak risk perception, limited management commitment, worker incompetence, flawed design systems, and inadequate planning. This research aims to develop a human factor engineering model to support the reduction of the Total Recordable Incident Frequency (TRIFR) in Oil and Gas construction activities in Nigeria. The study involved site-based construction workers with a minimum of 2 years' experience in upstream, downstream, and midstream Oil construction industries. Data collection utilized a descriptive study design with structured questionnaires, and analysis employed SPSS-AMOS and Structural Equation Modelling (SEM) techniques. Results indicated statistically significant correlations between human factors and TRIFR across workplace, task, personal, organizational, and design factors. The structural equation regression model further demonstrated the significance of human factors in relation to TRIFR. Specifically, path coefficients of 0.18, -0.4, 0.31, -1.06, and -0.21 were observed for personal, organizational, workplace, design, and task factors, respectively. In conclusion, the research proposes that engineered human factors can effectively contribute to reducing the total incident frequency rate. Recommendations include the establishment of a construction safety board by the Nigerian government, the implementation of integrated contractor construction health and safety management systems by organizations and workers embracing personal responsibility for safety to prevent or minimize incident frequency rates.

Challenges and experience of the Ethiopian rural health extension program: implications for reform and revitalization

BackgroundDespite remarkable gains over the past decade, mounting evidence suggests that Ethiopia’s rural health extension program (HEP) is facing serious implementation challenges. We investigated the current and potential future program design and implementation challenges of Ethiopia’s rural HEP based on the lived experiences of health extension workers (HEW) implementing the program at the grassroots level.MethodsWe employed a longitudinal qualitative exploration linked to a larger cluster-randomized trial (RCT) which was implemented in 282 villages randomly selected from 18 Kebeles of the Gedeo zone, southern Ethiopia. Data were collected using in-depth interviews with key informants, focus group discussion, and passive observation of program implementation. The data were analyzed manually using a thematic framework analysis approach. Themes and sub-themes were generated by condensing, summarizing, and synthesizing data collected in the field in the form of extended notes and field observation checklists.FindingsDespite considerable gains in availing basic health services to the rural population, HEP seems to suffer serious design and implementation flaws that demand thoughtful and immediate adjustment. The design constraints span from the number and type of intervention packages to the means of dissemination (vehicle) as well as the target population emphasized. As such, some low-cost high-impact interventions that were strongly desired by the community were overlooked, while others were inappropriately packed. The means of distribution - female health extension workers trained with basic prevention skills, were lacking essential skills. They also had high burnout rates and with little engagement with men, were repeatedly mentioned flaws of the program demanding revitalization. Furthermore, the sheer structure of HEP precluded adult and adolescent men, non-reproductive women, and the elderly.ConclusionDespite significant gains over the last couple of months, Ethiopia’s rural HEP appears to have reached a tipping point that requires a comprehensive revamp of the program package, means of distribution, and target beneficiaries rather than the “usual” tweaks to reap maximum benefits.