Design Errors Research Articles

Converting the energy of sea waves into electrical energy

AbstractThe study is highly relevant as ocean waves hold significant potential for producing electricity. Improvements in production, usage and rectification of research errors are crucial for meeting the energy demands of diverse consumers. The aim of this work is to put forward recommendations for eliminating design and implementation errors in wave energy conversion systems, specifically for offshore power plants, and to analyze their performance. Various methods were employed, including the analytical method, classification method, functional method, statistical method, synthesis method, and others. During the study, the characteristics and differences of ocean waves were observed, along with an analysis of the errors that can occur during the operation of offshore power plants designed for wave energy production and their associated causes. Uncertainties affecting the development of these power stations were identified, and the potential of sea waves as an energy resource was examined. Recommendations for enhanced regulation were put forward. The practicality lies in applying the identified findings to rectify errors in offshore power stations that use sea waves. This guarantees reliable operation by considering various factors and assists in recommending the optimal use of energy resources.

A fast approach for predicting stress intensity factors in tortuous cracks under mixed-mode loading

Realistic crack morphologies are generally sinuous rather than straight, which brings a great challenge to capture accurately the stress intensity factors at the crack tip. In this paper, a fast approximation method for predicting stress intensity factors in tortuous cracks under mixed-mode loading is proposed in terms of geometry simplification and semi-theoretical calculation. First, the finite element results show that the main and branch two-segment crack geometry approximation possesses a good capability of predicting the stress intensity factors of tortuous cracks under mixed-mode loading, whereas the simplification strategy of one straight crack cannot characterize the crack tip field of sinuous cracks. Then, an efficient semi-theoretical estimation approach is proposed to obtain the stress intensity factors of the branch crack from those of the main crack, which is validated to further reduce the computational time, resulting in a two-step accelerated operation. Moreover, the effect of main crack offset is also discussed and some recommendations are given to ensure accurate predictions within an acceptable margin of error for microstructural design or other application purposes.

Misclassification in Automated Content Analysis Causes Bias in Regression. Can We Fix It? Yes We Can!

ABSTRACT Automated classifiers (ACs), often built via supervised machine learning (SML), can categorize large, statistically powerful samples of data ranging from text to images and video. They have become widely popular measurement devices in communication science and related fields. Despite this popularity, even highly accurate classifiers make errors that cause misclassification bias and misleading results when input to downstream statistical analyses–unless such analyses account for these errors. As we show in a systematic literature review of SML applications, communication scholars largely ignore misclassification bias. In principle, existing statistical methods can use “gold standard” validation data, such as that created by human annotators, to correct misclassification bias. We introduce and test such methods, including a new method we design and implement in the R package misclassification_models, via Monte Carlo simulations designed to reveal each method’s limitations, which we also release. Based on our results, we recommend our new error correction method as it is versatile and efficient. In sum, automated classifiers, even those below common accuracy standards or those making systematic misclassifications, can be useful for measurement with careful study design and appropriate error correction methods.

Pragmatic clinical trials for localized prostate cancer: lessons learned and "three sins".

In "Explanatory and Pragmatic Attitudes in Therapeutic Trials", Schwatrz and Lelouch describe two approaches to the design of trials, "… the first "explanatory", the second "pragmatic". They explained "… the biologist may be interested to know whether the drugs differ in their effects … the explanatory approach". Biologically endpoints might determine whether it was better to give androgen deprivation therapy (ADT) before or after external beam radiation (EBRT) (i.e., does the sequence of treatments matter). Alternatively, if the arms focus on a clinical endpoint, this is considered … "the pragmatic approach". An example of a clinically relevant endpoint is overall survival (OS). A real-world example of this are the two randomized controlled trials (RCTs) evaluating the role of prophylactic whole pelvic radiotherapy (WPRT) conducted by the Radiation Therapy Oncology Group (RTOG). RTOG 9413 evaluated possible interactions between the sequence of drugs and volume irradiated, while RTOG/NRG 0924 focuses on OS. There appears to be a common pattern of "what not to do", or "design errors" made by a number of investigators, that I call the "three sins". I posit that the prospects for a well-designed pragmatic RCT are likely to be high if these "three sins" are avoided/minimized. The "three sins" alluded to are: 1. You can't prove something doesn't work by treating people who don't need the treatment. 2. You can't prove something does not work if the treatment is not done properly. 3. You can't prove something does not work with an underpowered study.

Impact of change orders on construction material waste in residential buildings projects

The current study attempts to address the relationship between material waste and change orders in residential building projects implemented in the West Bank in Palestine. The main objectives include: (1) identify the main factors affecting change orders in residential projects, (2) identify the main factors affecting martial waste eon construction sites, (3) address the relationship between change orders and construction material waste, (4) develop prediction model that shows the impact of change orders on material waste. To achieve this, two methods are used: (1) questionnaire survey is conducted to identify the main factors affecting change orders and the major factors of material waste on construction sites. Fourteen (14) factors believed to affect change orders and 15 factors that might affect material waste are investigated in this study. (2) Case study is conducted to address the impact of change orders on material waste. Data collected from 40 residential building projects implemented in the West Bank in Palestine. Regression analysis is used to establish the predictive model that relates the change orders and material waste. Results indicate that the top five factors affecting change orders include: change of project scope by owner, shortage in equipment and materials, change in materials, design mistakes, and change of plans by owner. It also shows that the top five factors affecting material waste are: rework, lack of labors skills, design errors, purchasing materials not complying with specifications, and frequent design changes. The results revealed a strong relationship between number of change orders and construction material waste on site.

Hybrid physics-guided data-driven modeling for generalizable geometric accuracy prediction and improvement in two-photon lithography

Two-photon lithography (TPL) is an additive manufacturing technique to produce three-dimensional (3D) micro- and nano-scale structures. Geometric accuracy is of vital importance to ensure the quality and functionality of additively manufactured 3D structures. However, there exists limited research on modeling and improving the geometric accuracy of TPL. Moreover, there is a lack of understanding of the influence of TPL process parameters (e.g., scanning rate, laser power) and structure design on the resulting geometric accuracy. This paper presents a new hybrid physics-guided data-driven modeling framework for generalizable cross-design and cross-parameter geometric accuracy prediction and improvement. The proposed model decomposes TPL-produced geometric features into two levels: a global trend and a spatial trend. Guided by physical laws that govern voxel dimensions, we construct the global trend as a function of TPL process parameters. Our new findings reveal strong linear relationships among the parameters of the global trend model across structure design dimensions, which enable generalizable predictive modeling. Moreover, the spatial trend captures the spatially varying patterns in geometric features. A large-scale experimental design consisting of six hemisphere sizes and six parameter combinations is carried out to thoroughly test the effectiveness of the proposed method. Our modeling approach demonstrates high accuracy in predicting the geometric error of a target design with knowledge derived from other designs and parameters. The average prediction errors for radius and height are 5.23% and 4.66%, respectively. Furthermore, the proposed compensation strategy is shown to reduce the geometric errors from 22.19% to 3.21% for radius, and from 12.18% to 4.96% for height. Meanwhile, the within-sample variations are greatly reduced, indicating improved process consistency. To the best of our knowledge, this study is among the first to develop a generalizable method for cross-design and cross-parameter geometric accuracy modeling and improvement in TPL.

Operational semantics in a domain-specific robot control language: A pedagogical use case

In this paper, we focus on some aspects of structural operational semantics for a selected domain-specific language for robot control. After defining a syntax for two independent languages for control of a robot?s movements, we define a structural operational semantics for them. The integrated part of structural operational semantics is abstract implementation, which consists of defining abstract machine and transformation of a programming language to abstract machine instructions. The achieved results as well as the mentioned research are a part of the research in the field of semantic methods, where we focus on the formalization of semantic methods for software engineering. This area is also very important for the training of students and young IT experts because the semantic methods can help to understand program behavior and detect errors in program design. To make the teaching of formal semantics in the field of domain-specific languages more attractive, we have also prepared an application that serves to visualize the individual steps of the program on an abstract machine ? simulation of translated code with visualization of a robot?s movement.

Closed-orbit Distortion study of XiPAF upgrading project synchrotron

Xi’an 200 MeV proton application facility (XiPAF) upgrading project is now in the design phase. A six super periods synchrotron is the main component of this project. Using MADX program, a statical analysis of the relationship between closed-orbit distortion (COD) and different types of magnet errors was carried out. Because we do not know the exact error in the design phase, we use rms value to represent errors and CODs. The results show that COD is in direct proportion to magnet error in some cases while the others are square proportional. We regard all the cases as direct proportional since the errors are usually small and find that the error amplification factors differ a lot. These results can give us some meaningful guide in lattice design and magnet error control.

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.

Electrical sensing properties of smart concrete enhanced with nano materials

The structures have to be assessed for its failures caused by design and construction errors, material deterioration, adverse environment effect hence monitoring the structural health has shown to be a reliable method of assuring the structural integrity. The advanced development of sensor technology and sensing material are the most attractive parts of evaluating structural health. The change in stress, strain, crack formation, temperature variation is measured using fiber optic sensors, piezometers and other sensor types are often utilized in health monitoring systems. Sensors can degrade over time due to exposure to moisture, temperature fluctuations, wearing and tearing or physical impacts. Additionally, installing and maintaining sensors can be costly. These restrictions might be addressed by incorporating sensing technology, such as smart sensing concrete, into concrete structures. This paper explores the piezo resistive properties in concrete by introducing functional fillers like carbon fiber, carbon nano tubes, graphene materials to make electrically conductive concrete that are used to assess its own deformation. This technology could lead to more efficient maintenance and repair processes, ultimately increasing the lifespan of buildings and bridges reduces the wastage of resources leads to sustainability

NLFEA Damage Assessment of RC Framed Buildings Subjected to Column Settlements

The prevention of progressive collapse in buildings caused by different actions, usually not considered in normal design, has attracted increasing interest in recent years. In Reinforced Concrete (RC) frames, a frequent cause of progressive collapse is represented by large settlements of one or more columns, caused e.g., by design or construction errors, underground works, or foundation failure. The focus of this work is to identify significant structural response parameters, which can be used both to assess the reliability level of existing structures subjected to large differential settlements, and to proper design Structural Health Monitoring (SHM) systems able to detect in real-time the triggering of possible structural issues. To this end, nonlinear finite element analyses are carried out, by considering different settlement scenarios. The applied procedure is first validated against experimental results from the literature, and then applied to the damage assessment of an existing Italian school building.

Shafting design and dynamic deformation error correction of two-dimensional laser tracking turntable

Shafting design and dynamic deformation error correction of two-dimensional laser tracking turntable

Internet of things temperature control of indirect dual tank heat storage system in solar photo-thermal power plant

In order to study the temperature control of the IoT for indirect dual tank heat storage systems in solar thermal power plants, the author proposes a refined design method for heat storage systems. Through CFD software FLUENT analysis, the author proposes a temperature control scheme for storage tanks in solar thermal power plants and applies this method to the temperature control and salt injection processes of actual commercial power plants. The refined design of a systematic heat storage system mainly involves precise calculation of molten salt content and refined analysis of overall and local stresses in the storage tank. For molten salt storage tanks with a diameter of about 30 m, every 1 cm of liquid level design error will result in economic losses of tens of thousands of Yuan. In addition, the design process of storage tanks should fully consider temperature control, salt injection, and some special operating conditions during operation. By numerically simulating the flow process of flue gas and molten salt in the storage tank and the real-time wall temperature of the storage tank, a temperature control scheme that does not exceed the maximum allowable wall temperature difference of the storage tank is obtained to reduce thermal stress during the temperature control process of the storage tank, reduce the risk and failure rate of the storage tank. The temperature control scheme has achieved good results in practical projects.

XMKR: Explainable manufacturing knowledge recommendation for collaborative design with graph embedding learning

Design for manufacturability is crucial to ensure high-quality products. It fully considers manufacturing-related factors in a collaborative design manner. However, since manufacturing knowledge is unstructured and hard to reuse, designers mainly depend on frequent design iterations to meet complex manufacturing constraints. Such insufficient design-manufacturing collaboration is not conducive to design efficiency improvement. To alleviate the problem, this paper proposes a novel graph embedding-based approach of Explainable Manufacturing Knowledge Recommendation (XMKR) for collaborative product design, which could achieve designer-oriented manufacturing knowledge reuse to avoid design errors proactively and minimize excessive iterations. Firstly, a graph embedding model based on the graph neural network (MKGE-GNN) is proposed to learn implicit semantic information of manufacturing knowledge. Secondly, with MKGE-GNN learning results, the potential manufacturing knowledge preferences of designers are identified in the design context graph by Personalized PageRank to achieve context-aware explainable manufacturing knowledge recommendation. Finally, a car body collaborative design case is conducted to validate the efficacy of the proposed approach, which not only provides accurate manufacturing knowledge in designers’ decision-making, but also enhances designers’ cognitions for manufacturability in the dynamic design context.

Economic assessment of ecological damage to surface waters as a result of emergency situation

The purpose of the present research is the analysis of emergence of the most probable emergency situations on the hydrotechnical object which is long time in operation, and also economic assessment of effects of surface water pollution of emergence of the emergency situation which resulted on hydrotechnical construction on the example of Raychikhinsky state district power plant. Hydrodynamic accidents happen because of design errors, constructive defects of constructions, violations of the rules of operation, discrepancy of spillways and spillovers of water through dams more often. Besides, it is impossible to miss possibility of acts of sabotage and blows to such constructions. Hydrodynamic accidents are consequence of failure of hydrotechnical constructions therefore the uncontrollable, powerful flow of huge mass of water with high speed floods extensive territories, bearing destructions and death of people. In the provided article the main characteristics of hydrotechnical constructions of Raychikhinsky state district power plant are in detail considered, the main dangers to the population at accidents on these constructions are defined, scenarios of possible accidents and emergency situations of natural and technogenic character are considered, economic assessment of the ecological damage caused to surface waters is provided. Safety of the population and steady functioning of the main objects of economy is provided with minimizing of probability of emergence and minimization of damage from the listed dangers.

Interactive rapid prototyping combining 3D Printing and Augmented Reality

In the development of new products by the industry, a rapid prototyping stage is recommended so that an initial version of the product can be evaluated. In this way, any necessary corrections can be applied while still in the prototyping stage, preventing design errors from reaching the final product. Augmented Reality (AR) and 3D Printing are techniques that have become ubiquitous in recent years due to the reduction of equipment costs. Several works in the area of rapid prototyping have been developed with one of these techniques in isolation; a few works have tried to unite these two tools. In this work, we propose a new functional rapid prototyping process, combining 3D Printing and AR to create functional interactive prototypes. This process is accomplished by projecting the AR onto the 3D-printed prototype. It interprets the user’s gestures on the physical prototype, converting clicks and touches into actions to be executed on the AR virtual prototype, making the prototype functional and interactive. The proposed system is evaluated by means of case studies and the application of the UEQ (User Experience Questionnaire) to users who have tested the system. This way, it is possible to evaluate the relevance of the proposed process.

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.

Influence of the Behaviour Coefficient on the Damage Level of an RC Elevated Tank under Seismic Loading

In Algeria, the seismic design of elevated concrete storage tanks is carried out in accordance with seismic standard, involving a behavior coefficient of the structure. This behaviour coefficient is used to determine the internal forces and to estimate the inelastic deformations undergone by the structure. For the elevated water tank, considered as reverse pendulum structure, this coefficient assumes a constant value (R=2) in the Algerian seismic code. Taking into account a single value, whatever the seismic zone, the site of implantation and the geometric characteristics of the structure, can lead to design errors leading to oversizing, hence an additional cost of the structure. Thus, faced with the need to design resistant structures while minimizing construction costs, it is important to precisely determine the value of this behaviour coefficient to introduce into the evaluation of the structure's response. In this research, the seismic performance of an RC elevated tank is analyzed, using a nonlinear approach based on the Pushover method, initially using the behavior coefficient prescribed by the Algerian seismic code, then secondly using the behavior coefficient approximated by a power-type law, taking into account the seismic zone, the type of soil, the height of the structure and the storage capacity. The results of this study highlight the influence of the value of the behavior coefficient on the seismic performance and the level of damage to an elevated tank.

The Development and Effectiveness of Game-Based Learning Prototypes for Daily Life Words at B1 Level: A Case Study of Engineering Students in Thailand

In order to communicate effectively, it is undeniable that language learners should have rich vocabularies. In this study, online games are proposed to be an effective learning method in language teaching and learning. The study aimed at constructing game prototypes–online intermediate daily life lexicon (IDLL) games, assessing quality of online IDLL games, and investigating effectiveness of these games. This study comprised two stages: design and evaluation.
 
 Quality of the online games was validated by four experts and 109 games players. Experts were asked to complete the IDLL evaluation form, whereas 109 game players were assigned to complete the learning experience questionnaire and learners’ satisfaction questionnaire. Effectiveness of the online games in relation to English vocabulary knowledge at B1 level was measured by the IDLL mini pretest and posttest. Quantitative data were analyzed by descriptive statistics, arithmetic mean, t-test dependent sample, and the effect size (ES) on learners’ gained scores. Qualitative data were investigated using content analysis of the IDLL evaluation form and learners’ satisfaction questionnaire.
 
 The findings revealed that the developed online games appear to be good learning material since both experts and learners view the games at the acceptable quality with sone revision needed further, such as learning content, game design, website design, technical limitation, and human errors. The findings also suggested that the developed online games were effective since students’ vocabulary knowledge had improved. Furthermore, students reported that they felt positive about the online games since they felt that they could learn in an enjoyable and interactive environment. Therefore, it was considered that this method can be used for teaching vocabulary within the Thai context. However, further development and revision were needed since the study was a trial process.

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.