Raihan Ahmed Joy, Md Solaiman Hawlader, Md Saifur Rahman, Md. Rafayat Hossain, Shariful Islam Shamim, Hosen Mahmud
Total quality management (TQM) is a methodical strategy to minimize defects through six processes including choosing the manufacturer, gathering information, identifying the issues, analyzing the current situation, and coming up with solutions, putting the plan into action, data collection, and result analysis. The study investigates how quality, productivity, and cost aspects of a sewing line can be improved by implementing (TQM) approach in an apparel manufacturing industry in Bangladesh. This research concentrates on reducing four primary types of faults in the sewing department of DMC Apparels Ltd., such as uncut thread, up-down, broken stitch, and joint stitch. Proper information on several stitching errors was provided by the operators and helpers and those are used to assess the study in the next step. Performing the Pareto analysis and histograms to identify the primary concerns are part of the analyzing process. Moreover, using the 10 TQM pillars, the implementation step entails establishing the TQM mindset in the sewing line of the apparel industry. Several data-gathering methods are utilized to analyze primary data throughout the study’s final phase. To analyze the acquired data, Microsoft Excel was employed. The percentage of defect per hundred unit was decreased by 1.51% after optimization, as the recommended solutions’ impact on the defect level in the section was found to be quite significant. Significant parameters such as efficiency, quality, and cost aspect were analyzed and showed positive changes after implementing the TQM approach. The new technical layout also allows for the saving of five employees and a 3,000-min labor expense reduction. Finally, the research was completed by analyzing the basic pitch time graph and calculating the overall equipment effectiveness.
{"title":"Improving Quality, Productivity, and Cost Aspects of a Sewing Line of Apparel Industry Using TQM Approach","authors":"Raihan Ahmed Joy, Md Solaiman Hawlader, Md Saifur Rahman, Md. Rafayat Hossain, Shariful Islam Shamim, Hosen Mahmud","doi":"10.1155/2024/6697213","DOIUrl":"https://doi.org/10.1155/2024/6697213","url":null,"abstract":"Total quality management (TQM) is a methodical strategy to minimize defects through six processes including choosing the manufacturer, gathering information, identifying the issues, analyzing the current situation, and coming up with solutions, putting the plan into action, data collection, and result analysis. The study investigates how quality, productivity, and cost aspects of a sewing line can be improved by implementing (TQM) approach in an apparel manufacturing industry in Bangladesh. This research concentrates on reducing four primary types of faults in the sewing department of DMC Apparels Ltd., such as uncut thread, up-down, broken stitch, and joint stitch. Proper information on several stitching errors was provided by the operators and helpers and those are used to assess the study in the next step. Performing the Pareto analysis and histograms to identify the primary concerns are part of the analyzing process. Moreover, using the 10 TQM pillars, the implementation step entails establishing the TQM mindset in the sewing line of the apparel industry. Several data-gathering methods are utilized to analyze primary data throughout the study’s final phase. To analyze the acquired data, Microsoft Excel was employed. The percentage of defect per hundred unit was decreased by 1.51% after optimization, as the recommended solutions’ impact on the defect level in the section was found to be quite significant. Significant parameters such as efficiency, quality, and cost aspect were analyzed and showed positive changes after implementing the TQM approach. The new technical layout also allows for the saving of five employees and a 3,000-min labor expense reduction. Finally, the research was completed by analyzing the basic pitch time graph and calculating the overall equipment effectiveness.","PeriodicalId":18319,"journal":{"name":"Mathematical Problems in Engineering","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139670013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The variation of frequency is a significant indicator of the operation status of rotating machinery. Generally, the frequency is extracted and tracked in real-time based on the vibration signal produced by the rotating machinery. However, various interferences generated from contact sampling and transmitting result in difficulty in obtaining the frequency correctly in real-time from the vibration. To solve this problem, this paper presents an interpolated Kalman filter (IKF) based on the vibration and surface noise signals for real-time frequency tracking. First, the cross-correlation operation is performed on the vibration and surface noise signals sampled synchronously to enhance the energy concentration. After that, a frequency search procedure is carried out to calculate the input of the tracking task. Finally, an IKF-based frequency lock procedure is applied to eliminate the interferences and track the frequency in real time. Besides, a correction procedure is added to prevent the measurement process from tracking the frequency incorrectly. The performance of the proposed method is verified by the experiments based on an ARM-based test bench using standard signals and actual test signals.
频率变化是旋转机械运行状态的一个重要指标。一般来说，频率是根据旋转机械产生的振动信号实时提取和跟踪的。然而，由于接触式采样和传输会产生各种干扰，因此很难从振动中实时正确地获取频率。为解决这一问题，本文提出了一种基于振动和表面噪声信号的插值卡尔曼滤波器（IKF），用于实时频率跟踪。首先，对同步采样的振动信号和表面噪声信号进行交叉相关运算，以提高能量集中度。然后，执行频率搜索程序，计算跟踪任务的输入。最后，应用基于 IKF 的频率锁定程序来消除干扰并实时跟踪频率。此外，还添加了一个校正程序，以防止测量过程中出现频率跟踪错误。基于 ARM 的测试台使用标准信号和实际测试信号进行实验，验证了所提方法的性能。
{"title":"Real-Time Frequency-Tracking Method Based on Interpolated Kalman Filter Using Vibration and Surface Noise","authors":"Chengcheng Li, Yuan Wan, Pingheng Pan, Bian Hu, Junhao Zhang","doi":"10.1155/2024/4418858","DOIUrl":"https://doi.org/10.1155/2024/4418858","url":null,"abstract":"The variation of frequency is a significant indicator of the operation status of rotating machinery. Generally, the frequency is extracted and tracked in real-time based on the vibration signal produced by the rotating machinery. However, various interferences generated from contact sampling and transmitting result in difficulty in obtaining the frequency correctly in real-time from the vibration. To solve this problem, this paper presents an interpolated Kalman filter (IKF) based on the vibration and surface noise signals for real-time frequency tracking. First, the cross-correlation operation is performed on the vibration and surface noise signals sampled synchronously to enhance the energy concentration. After that, a frequency search procedure is carried out to calculate the input of the tracking task. Finally, an IKF-based frequency lock procedure is applied to eliminate the interferences and track the frequency in real time. Besides, a correction procedure is added to prevent the measurement process from tracking the frequency incorrectly. The performance of the proposed method is verified by the experiments based on an ARM-based test bench using standard signals and actual test signals.","PeriodicalId":18319,"journal":{"name":"Mathematical Problems in Engineering","volume":"329 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139579814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Erratum to “Dynamic Equivalent Modeling of Wind Farm Based on Dominant Variable Hierarchical Clustering Algorithm”","authors":"Wenbo Jiang, Mingyue Zhong","doi":"10.1155/2024/9797619","DOIUrl":"https://doi.org/10.1155/2024/9797619","url":null,"abstract":"<jats:p />","PeriodicalId":18319,"journal":{"name":"Mathematical Problems in Engineering","volume":"159 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140481895","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Meta-heuristic algorithms have the advantages of resilience, global optimization capacity, and coding flexibility, making them helpful in tackling difficult optimization issues. The enhanced wind-driven optimization (CHTWDO) that was proposed in this paper coupled the chaotic map approach and the hyperbolic tangent with the T-distribution mutation method. The initial air particles are evenly distributed in the system space through a tent mapping strategy. Meanwhile, the variation probability of the hyperbolic tangent model and the T-distribution variation method are used to improve the comprehensive performance of the algorithm. In this way, the global search accuracy and the ability of avoiding the extreme value of the algorithm can be taken into account. Combining the three strategies, CHTWDO had higher global search accuracy and a stronger ability to jump out of local extremum. Comparing with the eight meta-heuristic algorithms (including WDO) and the single strategy improved WDO on 24 test functions, the experimental results show that CHTWDO with two improved strategies has better convergence precision and faster convergence speed. Statistical tests such as Friedman’s and Wilcoxon’s rank-sum tests are used to determine significant differences between these comparison algorithms. Finally, CHTWDO also obtains the best results on four classical optimization problems in engineering applications, which verifies its practicality and effectiveness.
元启发式算法具有弹性大、全局优化能力强、编码灵活等优点，有助于解决困难的优化问题。本文提出的增强型风驱动优化（CHTWDO）将混沌图法和双曲正切法与 T 分布突变法结合起来。通过帐篷映射策略，初始空气粒子被均匀地分布在系统空间中。同时，利用双曲正切模型的变异概率和 T 分布变异法提高算法的综合性能。这样，就能兼顾算法的全局搜索精度和避免极值的能力。综合三种策略，CHTWDO 的全局搜索精度更高，跳出局部极值的能力更强。在 24 个测试函数上与 8 种元启发式算法（包括 WDO）和单一策略改进的 WDO 比较，实验结果表明采用两种改进策略的 CHTWDO 具有更好的收敛精度和更快的收敛速度。弗里德曼检验和威尔科克森秩和检验等统计检验用于确定这些比较算法之间的显著差异。最后，CHTWDO 还在工程应用中的四个经典优化问题上取得了最佳结果，验证了其实用性和有效性。
{"title":"Chaotic Wind-Driven Optimization with Hyperbolic Tangent Model and T-Distributed Mutation Strategy","authors":"Da Fang, Jun Yan, Quan Zhou","doi":"10.1155/2024/5570228","DOIUrl":"https://doi.org/10.1155/2024/5570228","url":null,"abstract":"Meta-heuristic algorithms have the advantages of resilience, global optimization capacity, and coding flexibility, making them helpful in tackling difficult optimization issues. The enhanced wind-driven optimization (CHTWDO) that was proposed in this paper coupled the chaotic map approach and the hyperbolic tangent with the <i>T</i>-distribution mutation method. The initial air particles are evenly distributed in the system space through a tent mapping strategy. Meanwhile, the variation probability of the hyperbolic tangent model and the <i>T</i>-distribution variation method are used to improve the comprehensive performance of the algorithm. In this way, the global search accuracy and the ability of avoiding the extreme value of the algorithm can be taken into account. Combining the three strategies, CHTWDO had higher global search accuracy and a stronger ability to jump out of local extremum. Comparing with the eight meta-heuristic algorithms (including WDO) and the single strategy improved WDO on 24 test functions, the experimental results show that CHTWDO with two improved strategies has better convergence precision and faster convergence speed. Statistical tests such as Friedman’s and Wilcoxon’s rank-sum tests are used to determine significant differences between these comparison algorithms. Finally, CHTWDO also obtains the best results on four classical optimization problems in engineering applications, which verifies its practicality and effectiveness.","PeriodicalId":18319,"journal":{"name":"Mathematical Problems in Engineering","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139579518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lightning is one of the natural hazards that any aircraft may encounter while navigating. If adequate precautions are not taken against lightning, structural damage, operational disruptions, and loss of life and property can occur. Thus, studying the mechanism of damage caused by lightning strikes in an aircraft’s structural material is necessary to optimize the structure, minimize the damage, and reduce the cost caused by lightning. In the present article, the lightning-induced damage behavior of an aircraft structural material was investigated from an analytical perspective. For this purpose, two analytical-based models were developed: an improved electromagnetic pressure impact model (IEPIM) and the damage model in an aircraft wing. For the IEPIM, the findings of the article showed that the proposed pressure model is in good agreement with the experimental studies, borrowed from the open literature, for 100 and 200 kA lightning current. For the damage model, the findings of the article indicated that (i) even though lightning strikes to the regions with the same characteristics on an aircraft wing in terms of the lightning strike zone, the amount of deflection in the wing increases as the impact point approaches the wing tip and decreases as it approaches the wing root, (ii) without changing the lightning strike point (), when the damping coefficient () is increased in the range of , the amount of deflection decreases as the amount of damping coefficient increases, and (iii) when lightning wit
雷电是任何飞机在航行时都可能遇到的自然灾害之一。如果不采取足够的预防措施来应对雷击，就会造成结构损坏、运行中断以及生命和财产损失。因此，有必要研究雷击对飞机结构材料造成破坏的机理，以优化结构，最大限度地减少雷击造成的损失，降低成本。本文从分析角度研究了飞机结构材料的雷击诱发损伤行为。为此，我们开发了两个基于分析的模型：改进的电磁压力冲击模型（IEPIM）和飞机机翼损坏模型。对于 IEPIM，文章的研究结果表明，所提出的压力模型与公开文献中关于 100 和 200 kA 雷电电流的实验研究结果非常吻合。对于损坏模型，文章的研究结果表明：(i) 即使雷电击中的区域与飞机机翼上的雷击区特征相同，机翼的挠曲量也会随着雷击点接近翼尖而增加，随着雷击点接近翼根而减少；(ii) 在不改变雷击点（）的情况下，当阻尼系数（）为 0 时，机翼的挠曲量为 0；当阻尼系数（）为 0 时，机翼的挠曲量为 0、(iii) 当电流为 100 kA 的闪电击中飞机翼根时，闪电的压力冲击在翼根造成的扭转挠度大于弯曲挠度；然而，当闪电击中飞机的中翼或翼尖时，闪电的压力冲击在中翼或翼尖造成的弯曲挠度大于扭转挠度。
{"title":"An Analytical-Based Lightning-Induced Damage Model for an Aircraft Wing Exposed to Pressure Loading of Lightning","authors":"Aysun Soysal, Ibrahim Ozkol, Erol Uzal","doi":"10.1155/2024/8313135","DOIUrl":"https://doi.org/10.1155/2024/8313135","url":null,"abstract":"Lightning is one of the natural hazards that any aircraft may encounter while navigating. If adequate precautions are not taken against lightning, structural damage, operational disruptions, and loss of life and property can occur. Thus, studying the mechanism of damage caused by lightning strikes in an aircraft’s structural material is necessary to optimize the structure, minimize the damage, and reduce the cost caused by lightning. In the present article, the lightning-induced damage behavior of an aircraft structural material was investigated from an analytical perspective. For this purpose, two analytical-based models were developed: an improved electromagnetic pressure impact model (IEPIM) and the damage model in an aircraft wing. For the IEPIM, the findings of the article showed that the proposed pressure model is in good agreement with the experimental studies, borrowed from the open literature, for 100 and 200 kA lightning current. For the damage model, the findings of the article indicated that (i) even though lightning strikes to the regions with the same characteristics on an aircraft wing in terms of the lightning strike zone, the amount of deflection in the wing increases as the impact point approaches the wing tip and decreases as it approaches the wing root, (ii) without changing the lightning strike point (<span><svg height=\"9.25202pt\" style=\"vertical-align:-3.29111pt\" version=\"1.1\" viewbox=\"-0.0498162 -5.96091 12.2751 9.25202\" width=\"12.2751pt\" xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"><g transform=\"matrix(.013,0,0,-0.013,0,0)\"></path></g><g transform=\"matrix(.0091,0,0,-0.0091,7.202,3.132)\"></path></g></svg>),</span> when the damping coefficient (<span><svg height=\"12.2089pt\" style=\"vertical-align:-2.503pt\" version=\"1.1\" viewbox=\"-0.0498162 -9.7059 5.94546 12.2089\" width=\"5.94546pt\" xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"><g transform=\"matrix(.013,0,0,-0.013,0,0)\"></path></g></svg>)</span> is increased in the range of <span><svg height=\"12.2089pt\" style=\"vertical-align:-2.503pt\" version=\"1.1\" viewbox=\"-0.0498162 -9.7059 13.689 12.2089\" width=\"13.689pt\" xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"><g transform=\"matrix(.013,0,0,-0.013,0,0)\"></path></g><g transform=\"matrix(.013,0,0,-0.013,4.485,0)\"></path></g><g transform=\"matrix(.013,0,0,-0.013,10.725,0)\"></path></g></svg><span></span><span><svg height=\"12.2089pt\" style=\"vertical-align:-2.503pt\" version=\"1.1\" viewbox=\"15.8181838 -9.7059 16.762 12.2089\" width=\"16.762pt\" xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"><g transform=\"matrix(.013,0,0,-0.013,15.868,0)\"></path></g><g transform=\"matrix(.013,0,0,-0.013,22.108,0)\"><use xlink:href=\"#g113-236\"></use></g><g transform=\"matrix(.013,0,0,-0.013,27.933,0)\"></path></g></svg>,</span></span> the amount of deflection decreases as the amount of damping coefficient increases, and (iii) when lightning wit","PeriodicalId":18319,"journal":{"name":"Mathematical Problems in Engineering","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139579517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Malaria is a complex disease with many factors influencing the transmission dynamics, including age. This research analyzes the transmission dynamics of malaria by developing an age-structured mathematical model using the classical integer order and Atangana–Baleanu–Caputo fractional operators. The analysis of the model focused on several important aspects. The existence and uniqueness of solutions of fractional order were explored based on some fixed-point theorems,such as Banach and Krasnoselski. The Positivity and boundedness of the solutions were also investigated. Furthermore, through mathematical analysis techniques, we analyzed different types of stability results, and the results showed that the disease-free equilibrium point of the model is proved to be both locally and globally asymptotically stable if the basic reproduction number is less than one, whereas the endemic equilibrium point of the model is both locally and globally asymptotically stable if the basic reproduction number is greater than one. The findings from the sensitivity analysis revealed that the most sensitive parameters, essential for controlling or eliminating malaria are mosquito biting rate, density-dependent natural mortality rate, clinical recovery rate, and recruitment rate for mosquitoes. Numerical simulations are also performed to examine the behavior of the model for different values of the fractional-order alpha,and the result revealed that as the value α reduces from 1, the spread of the endemic grows slower. By incorporating these findings, this research helps to clarify the dynamics of malaria and provides information on how to create efficient control measures.
{"title":"Analysis of Age-Structured Mathematical Model of Malaria Transmission Dynamics via Classical and ABC Fractional Operators","authors":"Ademe Kebede Gizaw, Chernet Tuge Deressa","doi":"10.1155/2024/3855146","DOIUrl":"https://doi.org/10.1155/2024/3855146","url":null,"abstract":"Malaria is a complex disease with many factors influencing the transmission dynamics, including age. This research analyzes the transmission dynamics of malaria by developing an age-structured mathematical model using the classical integer order and Atangana–Baleanu–Caputo fractional operators. The analysis of the model focused on several important aspects. The existence and uniqueness of solutions of fractional order were explored based on some fixed-point theorems,such as Banach and Krasnoselski. The Positivity and boundedness of the solutions were also investigated. Furthermore, through mathematical analysis techniques, we analyzed different types of stability results, and the results showed that the disease-free equilibrium point of the model is proved to be both locally and globally asymptotically stable if the basic reproduction number is less than one, whereas the endemic equilibrium point of the model is both locally and globally asymptotically stable if the basic reproduction number is greater than one. The findings from the sensitivity analysis revealed that the most sensitive parameters, essential for controlling or eliminating malaria are mosquito biting rate, density-dependent natural mortality rate, clinical recovery rate, and recruitment rate for mosquitoes. Numerical simulations are also performed to examine the behavior of the model for different values of the fractional-order alpha,and the result revealed that as the value <i>α</i> reduces from 1, the spread of the endemic grows slower. By incorporating these findings, this research helps to clarify the dynamics of malaria and provides information on how to create efficient control measures.","PeriodicalId":18319,"journal":{"name":"Mathematical Problems in Engineering","volume":"117 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139554463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Venture capitalists invest not only in the business aspect of a deal but also in its contractual terms. Therefore, the selection of deals and the combination of contractual terms pose challenging decisions for them. This paper consists of two main sections. The first section introduces a novel framework for the valuation of venture capital (VC) deals, including startups and their contractual terms. By taking into account risk situations, this section presents the valuation of combined contractual terms, including call options, liquidity preference, and participant rights. In the second section, a new multiobjective mathematical model for VC deals and contractual terms portfolio selection is developed using right-tail probability, strategy alignment, and a utility function. To solve the proposed model, three metaheuristic algorithms—Non-Dominated Sorting Genetic Algorithm (NSGA-II), Multi-Objective Binary Harmony Search Algorithm, and Dynamic Tuning Parameter Binary Harmony Search Algorithm (DTPBHS)—are applied. Based on numerical examples, DTPBHS outperforms other algorithms in the “Mean Ideal Distance” index, but NSGA-II demonstrates the best performance in the “Rate of Achievement of two objectives simultaneously” index. Furthermore, we demonstrate that the proposed utility function is more robust than the right-tail probability function under default deals conditions.
{"title":"A Framework for Valuation and Portfolio Optimization of Venture Capital Deals with Contractual Terms","authors":"Mohammadreza Valaei, Vahid Khodakarami","doi":"10.1155/2024/3427721","DOIUrl":"https://doi.org/10.1155/2024/3427721","url":null,"abstract":"Venture capitalists invest not only in the business aspect of a deal but also in its contractual terms. Therefore, the selection of deals and the combination of contractual terms pose challenging decisions for them. This paper consists of two main sections. The first section introduces a novel framework for the valuation of venture capital (VC) deals, including startups and their contractual terms. By taking into account risk situations, this section presents the valuation of combined contractual terms, including call options, liquidity preference, and participant rights. In the second section, a new multiobjective mathematical model for VC deals and contractual terms portfolio selection is developed using right-tail probability, strategy alignment, and a utility function. To solve the proposed model, three metaheuristic algorithms—Non-Dominated Sorting Genetic Algorithm (NSGA-II), Multi-Objective Binary Harmony Search Algorithm, and Dynamic Tuning Parameter Binary Harmony Search Algorithm (DTPBHS)—are applied. Based on numerical examples, DTPBHS outperforms other algorithms in the “Mean Ideal Distance” index, but NSGA-II demonstrates the best performance in the “Rate of Achievement of two objectives simultaneously” index. Furthermore, we demonstrate that the proposed utility function is more robust than the right-tail probability function under default deals conditions.","PeriodicalId":18319,"journal":{"name":"Mathematical Problems in Engineering","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139554489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
As a kind of thermal control device, fluid loop systems must operate with the demands of high safety, high reliability, and long life. In order to accurately assess the health status of fluid loop systems, a hierarchical multi-information fusion (HMIF) method is proposed in this paper. Considering that fluid loop systems generally have distinct structural hierarchies, the health evaluation process in this method is divided into three levels, which are the indicator level, the component level, and the system level. In the evaluation process, the health indices are, respectively, constructed to quantify the health status at the three levels. At the indicator level, One-Class support vector machine algorithm is used to obtain the distribution space of each state monitoring indicator under a normal state. The indicator-level health indices are evaluated by calculating the ratio of the data located in the distribution space to the overall data. At the component level, a fuzzy theory is used to calculate the health indices of the component level. Health indices at the indicator level are first converted to membership degree by membership degree function. Then, the evaluation fusion strategy is used to deduce the membership degree of the component level. The health indices at the component level are obtained from the mapping relationship between the membership degree and the health index. At the system level, an adaptive weight adjustment strategy is proposed to fuze all component-level health indices. Taking a practical fluid loop system as an example, health indices at the three levels evaluated by the HMIF method are compared with the actual status. The results indicate that the proposed method can correctly judge the health state of the system and provide a reference for the maintenance and fault diagnosis of fluid loop systems.
{"title":"A Health Status Assessment Method of Fluid Loop System Based on Hierarchical Multi-Information Fusion","authors":"Rui Li, Junshen Zhang, Hongzheng Fang, Qing Zhang","doi":"10.1155/2024/5088057","DOIUrl":"https://doi.org/10.1155/2024/5088057","url":null,"abstract":"As a kind of thermal control device, fluid loop systems must operate with the demands of high safety, high reliability, and long life. In order to accurately assess the health status of fluid loop systems, a hierarchical multi-information fusion (HMIF) method is proposed in this paper. Considering that fluid loop systems generally have distinct structural hierarchies, the health evaluation process in this method is divided into three levels, which are the indicator level, the component level, and the system level. In the evaluation process, the health indices are, respectively, constructed to quantify the health status at the three levels. At the indicator level, One-Class support vector machine algorithm is used to obtain the distribution space of each state monitoring indicator under a normal state. The indicator-level health indices are evaluated by calculating the ratio of the data located in the distribution space to the overall data. At the component level, a fuzzy theory is used to calculate the health indices of the component level. Health indices at the indicator level are first converted to membership degree by membership degree function. Then, the evaluation fusion strategy is used to deduce the membership degree of the component level. The health indices at the component level are obtained from the mapping relationship between the membership degree and the health index. At the system level, an adaptive weight adjustment strategy is proposed to fuze all component-level health indices. Taking a practical fluid loop system as an example, health indices at the three levels evaluated by the HMIF method are compared with the actual status. The results indicate that the proposed method can correctly judge the health state of the system and provide a reference for the maintenance and fault diagnosis of fluid loop systems.","PeriodicalId":18319,"journal":{"name":"Mathematical Problems in Engineering","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139554668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cost management is a crucial component of construction project management, which assumes an increasingly critical role in modern large-scale projects. Ideally, cost management is achieved through a comparison between the current cost and the predetermined cost schedule. However, in real-world projects, it is often difficult to consistently obtain accurate costs for each cost item throughout the project life cycle and to predict the probability of various risk occurrences. To address this challenge, we propose a novel building information modeling- (BIM-) based algorithm to quantify the risk of cost overruns and cost deviation; and identify the primary causes without a detailed cost breakdown. The role of BIM in our approach is to automatically extract precise quantitative information that we can use to calculate the probability density function of the current cost and the expected total cost and eventually combine reliability analysis to provide the risk probability. The numerical experiment demonstrates that this algorithm can estimate the probability of cost overruns and cost deviation, and identify the primary cause of deviation. Additionally, the sensitivity requirements for cost management can be adjusted by adjusting the parameters, indicating its potential to meet multiple requirements in the different projects. The proposed algorithm provides a method for detecting the current risk of cost overruns and cost deviation, as well as identifying the primary cause of deviation, which is of potential value in the practical applications.
{"title":"Novel Probabilistic Approach for Quantification of Cost-Overruns Risk and Determination of Primary Causes","authors":"Tianyu Liu, Shen Zhang, Xingyu Wang","doi":"10.1155/2024/8893201","DOIUrl":"https://doi.org/10.1155/2024/8893201","url":null,"abstract":"Cost management is a crucial component of construction project management, which assumes an increasingly critical role in modern large-scale projects. Ideally, cost management is achieved through a comparison between the current cost and the predetermined cost schedule. However, in real-world projects, it is often difficult to consistently obtain accurate costs for each cost item throughout the project life cycle and to predict the probability of various risk occurrences. To address this challenge, we propose a novel building information modeling- (BIM-) based algorithm to quantify the risk of cost overruns and cost deviation; and identify the primary causes without a detailed cost breakdown. The role of BIM in our approach is to automatically extract precise quantitative information that we can use to calculate the probability density function of the current cost and the expected total cost and eventually combine reliability analysis to provide the risk probability. The numerical experiment demonstrates that this algorithm can estimate the probability of cost overruns and cost deviation, and identify the primary cause of deviation. Additionally, the sensitivity requirements for cost management can be adjusted by adjusting the parameters, indicating its potential to meet multiple requirements in the different projects. The proposed algorithm provides a method for detecting the current risk of cost overruns and cost deviation, as well as identifying the primary cause of deviation, which is of potential value in the practical applications.","PeriodicalId":18319,"journal":{"name":"Mathematical Problems in Engineering","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139495799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This research paper presents a new iterative method (NIM) for obtaining the solution to the potential Kadomtsev–Petviashvili (PKP) equation. NIM is a promising approach to solving complex mathematical problems, and its effectiveness and efficiency are highlighted through its application to the PKP equation. The results obtained through the use of NIM are compared to the exact solutions of the PKP equation, and it is found that the NIM approach provides results that are in close agreement with the exact solutions. This demonstrates the utility and accuracy of NIM and makes it a valuable tool for solving similar mathematical problems in the future. Furthermore, the lack of discretization in the NIM approach makes it a more convenient method for solving the PKP equation compared to traditional approaches that require discretization. Overall, the findings of this research paper suggest that NIM is a highly effective and convenient method for obtaining approximate analytical solutions to complex mathematical problems, such as the -dimensional PKP equation.
本研究论文介绍了一种新的迭代法（NIM），用于获得潜在的卡多姆采夫-彼得维亚什维利（PKP）方程的解。NIM 是解决复杂数学问题的一种有前途的方法，它在 PKP 方程中的应用凸显了其有效性和效率。通过将使用 NIM 所获得的结果与 PKP 方程的精确解进行比较，发现 NIM 方法所提供的结果与精确解非常接近。这证明了 NIM 的实用性和准确性，使其成为今后解决类似数学问题的重要工具。此外，与需要离散化的传统方法相比，NIM 方法不需要离散化，因此是一种更方便的 PKP 方程求解方法。总之，本文的研究结果表明，NIM 是一种高效便捷的方法，可用于获得复杂数学问题（如-维 PKP 方程）的近似解析解。
{"title":"Innovative Solutions for the Kadomtsev–Petviashvili Equation via the New Iterative Method","authors":"Belal Batiha","doi":"10.1155/2024/5541845","DOIUrl":"https://doi.org/10.1155/2024/5541845","url":null,"abstract":"This research paper presents a new iterative method (NIM) for obtaining the solution to the potential Kadomtsev–Petviashvili (PKP) equation. NIM is a promising approach to solving complex mathematical problems, and its effectiveness and efficiency are highlighted through its application to the PKP equation. The results obtained through the use of NIM are compared to the exact solutions of the PKP equation, and it is found that the NIM approach provides results that are in close agreement with the exact solutions. This demonstrates the utility and accuracy of NIM and makes it a valuable tool for solving similar mathematical problems in the future. Furthermore, the lack of discretization in the NIM approach makes it a more convenient method for solving the PKP equation compared to traditional approaches that require discretization. Overall, the findings of this research paper suggest that NIM is a highly effective and convenient method for obtaining approximate analytical solutions to complex mathematical problems, such as the <span><svg height=\"11.5564pt\" style=\"vertical-align:-2.26807pt\" version=\"1.1\" viewbox=\"-0.0498162 -9.28833 21.275 11.5564\" width=\"21.275pt\" xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"><g transform=\"matrix(.013,0,0,-0.013,0,0)\"></path></g><g transform=\"matrix(.013,0,0,-0.013,4.498,0)\"></path></g><g transform=\"matrix(.013,0,0,-0.013,13.644,0)\"></path></g></svg><span></span><span><svg height=\"11.5564pt\" style=\"vertical-align:-2.26807pt\" version=\"1.1\" viewbox=\"24.1301838 -9.28833 10.947 11.5564\" width=\"10.947pt\" xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\"><g transform=\"matrix(.013,0,0,-0.013,24.18,0)\"></path></g><g transform=\"matrix(.013,0,0,-0.013,30.42,0)\"></path></g></svg>-</span></span>dimensional PKP equation.","PeriodicalId":18319,"journal":{"name":"Mathematical Problems in Engineering","volume":"66 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139475890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：