Article
Operations Research & Management Science
Javad Asadkhani, Hadi Mokhtari, Saman Tahmasebpoor
Summary: This paper develops four economic order quantity models for different types of imperfect quality items and considers the impact of inspector's ability to reduce inspection errors through learning on profitability. Results from numerical examples and sensitivity analysis show that learning in inspection errors has a significant effect on profitability.
OPERATIONAL RESEARCH
(2022)
Article
Computer Science, Interdisciplinary Applications
Dipankar Bose, Apratim Guha
Summary: The choice between full inspection and sampling inspection usually depends on the threshold level of unit inspection cost. An online sampling inspection scheme can lead to significant savings in inventory holding costs and higher optimal expected profit. For high unit inspection costs, online sampling can result in a higher optimal expected profit compared to full inspection.
COMPUTERS & INDUSTRIAL ENGINEERING
(2021)
Article
Management
Li Xiao, Ce Wang
Summary: This study investigates a multi-location newsvendor problem with different random yield assumptions. Through cost analysis, the study compares centralized and decentralized systems and derives their expected costs and cost variances. The results suggest that centralization is better than decentralization when demand is deterministic or uncertain with a service level of 0.5, driven by the risk pooling effect. However, when demand is deterministic, decentralization is better due to the risk diversification effect. Numerical experiments show that there is generally no risk pooling effect or risk diversification effect when demand is uncertain. Specifically, under additive random yield, the cost variance of the centralized system can be either higher or lower than the decentralized system. Under multiplicative random yield, centralization is better in terms of the expected cost, while decentralization is better in terms of the cost variance. Both analytical and numerical results indicate that the comparison between centralization and decentralization depends heavily on the uncertainty of demand when considering supply uncertainty.
OMEGA-INTERNATIONAL JOURNAL OF MANAGEMENT SCIENCE
(2023)
Article
Engineering, Multidisciplinary
G. Karakatsoulis, K. Skouri
Summary: This paper explores the use of an (r, Q) stock policy to manage an inventory system with deterministic demand and defective items. A new reorder level is proposed to prevent shortages and minimize total costs. Theoretical results demonstrate significant cost reduction and probability of shortages compared to other existing models.
APPLIED MATHEMATICAL MODELLING
(2021)
Article
Computer Science, Interdisciplinary Applications
Nan Zhang, Sen Tian, Jiatao Xu, Yingjun Deng, Kaiquan Cai
Summary: This paper proposes an integrated Economic manufacturing quantity (EMQ) model that combines the concepts of condition-based maintenance (CBM) and imperfect manufacturing process. The manufacturing process is modeled by binary state indicators and a homogeneous Gamma process. An integrated production and CBM policy is proposed to minimize the expected cost rate in the long-term. The problem is solved using a semi-Markov decision process framework and the successive-approximations method.
COMPUTERS & INDUSTRIAL ENGINEERING
(2023)
Article
Engineering, Industrial
Ebrahim Sharifi, Javad Hasanpour, Ata Allah Taleizadeh
Summary: Effective management and control of perishable inventories is crucial as it is more complex and challenging than inventories with unlimited lifetime. This paper developed an optimal inventory policy for perishable products, validated it using numerical examples and performed sensitivity analysis.
INTERNATIONAL JOURNAL OF SYSTEMS SCIENCE-OPERATIONS & LOGISTICS
(2021)
Article
Computer Science, Interdisciplinary Applications
Omid Jadidi, Mohamad Y. Jaber, Saeed Zolfaghri, Roberto Pinto, Fatemeh Firouzi
Summary: This study investigates the joint pricing and sourcing decision problem for a buyer purchasing a product from multiple suppliers. It formulates the problem as a mixed-integer nonlinear programming one and presents various strategies for maximizing the buyer's expected profit, with numerical examples provided for discussion and analysis.
COMPUTERS & INDUSTRIAL ENGINEERING
(2021)
Article
Microbiology
Zonghan Yue, Wei Zhang, Wenjun Liu, Jia Xu, Wen Liu, Xinyu Zhang
Summary: This study investigated the effects of different light quality and intensity conditions on the yield and quality of Pleurotus eryngii. The results showed that the red light treatment samples had higher yield and nutritional quality compared to the white light control, and the energy consumption of the red LED light source was the lowest.
Article
Computer Science, Artificial Intelligence
Zhiming Chen, Fanglong Liu
Summary: Outsourcing is a popular production mode that benefits both OEMs and CMs. Research shows that there is a threshold outsourcing price beyond which CMs are motivated to overproduce, and in a competitive market, price war is not a wise strategy for CMs.
EXPERT SYSTEMS WITH APPLICATIONS
(2021)
Article
Mathematics
Leopoldo Eduardo Cardenas-Barron, Osman Albert Marquez-Rios, Irene Sanchez-Romero, Buddhadev Mandal
Summary: This research paper presents an EOQ inventory model for imperfect quality products with nonlinear demand dependent on price. It includes a 100% screening process upon receiving a batch to identify imperfect and perfect products. The optimization of batch size, backordering level, and selling price aims to maximize expected total profit.
REVISTA DE LA REAL ACADEMIA DE CIENCIAS EXACTAS FISICAS Y NATURALES SERIE A-MATEMATICAS
(2022)
Article
Multidisciplinary Sciences
Hesham K. Alfares, Abdul Rehman Afzal
Summary: This paper extends inventory models for growing items by considering quality aspects, permissible shortages with complete backordering, and holding cost during both the growth period and the consumption period. A nonlinear programming model is used to determine the optimum cycle length and shortage level in order to minimize the total costs of the inventory system.
ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING
(2021)
Article
Management
Viktor Bindewald, Fabian Dunke, Stefan Nickel
Summary: This paper studies a new variant of the lot sizing problem with uncertain demand and planning horizon. It proposes a rolling horizon procedure to dissolve the multistage problem into a series of snapshot problems under uncertainty. Different approaches such as online optimization, stochastic programming, and robust optimization are evaluated to model and solve the snapshot problems based on available data and risk disposition. The impact of the selected methodology on the overall solution quality is evaluated using a methodology-agnostic framework for multistage decision-making under uncertainty. Computational results on lot sizing within a rolling horizon are provided regarding different types of uncertainty, solution approaches, and the value of available information about upcoming demands.
INTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH
(2023)
Article
Engineering, Industrial
Zsuzsanna Hauck, Boualem Rabta, Gerald Reiner
Summary: The research indicates that applying the optimal screening time can lead to higher profits through increased selling prices, cost savings, and improved customer satisfaction. However, it is important to consider the parameters of the demand function, the cost and reliability of the screening method, and the initial quality level in order to avoid overinvestment in quality.
INTERNATIONAL JOURNAL OF PRODUCTION ECONOMICS
(2021)
Article
Plant Sciences
Jie He, Su Yee Leng, Lin Qin
Summary: Salinity negatively affects the yield, physiology, and nutritional quality of purslane, while LED spectral quality only has an impact on certain physiological and nutritional parameters.
Article
Engineering, Industrial
Nan Zhang, Sen Tian, Bin Liu, Jun Zhang
Summary: This paper addresses the integrated optimization of economic manufacturing quantity and condition-based maintenance policy for a deteriorating manufacturing system. It develops an integrated production and maintenance model considering the inter-dependencies between the production process and machine degradation. The objective is to minimize the overall cost by jointly optimizing the lot-sizing and maintenance policy.
QUALITY TECHNOLOGY AND QUANTITATIVE MANAGEMENT
(2023)
Article
Engineering, Multidisciplinary
A. A. Aganin, A. I. Davletshin
Summary: A mathematical model of interaction of weakly non-spherical gas bubbles in liquid is proposed in this paper. The model equations are more accurate and compact compared to existing analogs. Five problems are considered for validation, and the results show good agreement with experimental data and numerical solutions. The model is also used to analyze the behavior of bubbles in different clusters, providing meaningful insights.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Hao Wu, Jie Sun, Wen Peng, Lei Jin, Dianhua Zhang
Summary: This study establishes an analytical model for the coupling of temperature, deformation, and residual stress to explore the mechanism of residual stress formation in hot-rolled strip and how to control it. The accuracy of the model is verified by comparing it with a finite element model, and a method to calculate the critical exit crown ratio to maintain strip flatness is proposed.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Shengwen Tu, Naoki Morita, Tsutomu Fukui, Kazuki Shibanuma
Summary: This study aimed to extend the finite element method to cope with elastic-plastic problems by introducing the s-version FEM. The s-version FEM, which overlays a set of local mesh with fine element size on the conventional FE mesh, simplifies domain discretisation and provides accurate numerical predictions. Previous applications of the s-version FEM were limited to elastic problems, lacking instructions for stress update in plasticity. This study presents detailed instructions and formulations for addressing plasticity problems with the s-version FEM and analyzes a stress concentration problem with linear/nonlinear material properties.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Bo Fan, Zhongmin Wang
Summary: A 3D rotating hyperelastic composite REF model was proposed to analyze the influence of tread structure and rotating angular speed on the vibration characteristics of radial tire. Nonlinear dynamic differential equations and modal equations were established to study the effects of internal pressure, tread pressure sharing ratio, belt structure, and rotating angular speed on the vibration characteristics.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
X. W. Chen, Z. Q. Yue, Wendal Victor Yue
Summary: This paper examines the axisymmetric problem of a flat mixed-mode annular crack near and parallel to an arbitrarily graded interface in functionally graded materials (FGMs). The crack is modeled as plane circular dislocation loop and an efficient solution for dislocation in FGMs is used to calculate the stress field at the crack plane. The analytical solutions of the stress intensity factors are obtained and numerical study is conducted to investigate the fracture mechanics of annular crack in FGMs.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Xumin Guo, Jianfei Gu, Hui Li, Kaihua Sun, Xin Wang, Bingjie Zhang, Rangwei Zhang, Dongwu Gao, Junzhe Lin, Bo Wang, Zhong Luo, Wei Sun, Hui Ma
Summary: In this study, a novel approach combining the transfer matrix method and lumped parameter method is proposed to analyze the vibration response of aero-engine pipelines under base harmonic and random excitations. The characteristics of the pipelines are investigated through simulation and experiments, validating the effectiveness of the proposed method.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Xiangyu Sha, Aizhong Lu, Ning Zhang
Summary: This paper investigates the stress and displacement of a layered soil with a fractional-order viscoelastic model under time-varying loads. The correctness of the solutions is validated using numerical methods and comparison with existing literature. The research findings are of significant importance for exploring soil behavior and its engineering applications under time-varying loads.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Thuy Dong Dang, Thi Kieu My Do, Minh Duc Vu, Ngoc Ly Le, Tho Hung Vu, Hoai Nam Vu
Summary: This paper investigates the nonlinear torsional buckling of corrugated core sandwich toroidal shell segments with functionally graded graphene-reinforced composite (FG-GRC) laminated coatings in temperature change using the Ritz energy method. The results show the significant beneficial effects of FG-GRC laminated coatings and corrugated core on the nonlinear buckling responses of structures.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Zhihao Zhai, Chengbiao Cai, Qinglai Zhang, Shengyang Zhu
Summary: This paper investigates the effect of localized cracks induced by environmental factors on the dynamic performance and service life of ballastless track in high-speed railways. A mathematical approach for forced vibrations of Mindlin plates with a side crack is derived and implemented into a train-track coupled dynamic system. The accuracy of this approach is verified by comparing with simulation and experimental results, and the dynamic behavior of the side crack under different conditions is analyzed.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
James Vidler, Andrei Kotousov, Ching-Tai Ng
Summary: The far-field methodology, developed by J.C. Maxwell, is utilized to estimate the effective third order elastic constants of composite media containing random distribution of spherical particles. The results agree with previous studies and can be applied to homogenization problems in other fields.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Kim Q. Tran, Tien-Dat Hoang, Jaehong Lee, H. Nguyen-Xuan
Summary: This study presents novel frameworks for graphene platelets reinforced functionally graded triply periodic minimal surface (GPLR-FG-TPMS) plates and investigates their performance through static and free vibration analyses. The results show that the mass density framework has potential for comparing different porous cores and provides a low weight and high stiffness-to-weight ratio. Primitive plates exhibit superior performance among thick plates.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Bence Hauck, Andras Szekrenyes
Summary: This study explores several methods for computing the J-integral in laminated composite plate structures with delamination. It introduces two special types of plate finite elements and a numerical algorithm. The study presents compact formulations for calculating the J-integral and applies matrix multiplication to take advantage of plate transition elements. The models and algorithms are applied to case studies and compared with analytical and previously used finite element solutions.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Wu Ce Xing, Jiaxing Wang, Yan Qing Wang
Summary: This paper proposes an effective mathematical model for bolted flange joints to study their vibration characteristics. By modeling the flange and bolted joints, governing equations are derived. Experimental studies confirm that the model can accurately predict the vibration characteristics of multiple-plate structures.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Pingchao Yu, Li Hou, Ke Jiang, Zihan Jiang, Xuanjun Tao
Summary: This paper investigates the imbalance problem in rotating machinery and finds that mass imbalance can induce lateral-torsional coupling vibration. By developing a model and conducting detailed analysis, it is discovered that mass imbalance leads to nonlinear time-varying characteristics and there is no steady-state torsional vibration in small unbalanced rotors. Under largely unbalanced conditions, both resonant and unstable behavior can be observed, and increasing lateral damping can suppress instability and reduce lateral amplitude in the resonance region.
APPLIED MATHEMATICAL MODELLING
(2024)
Article
Engineering, Multidisciplinary
Yong Cao, Ziwen Guo, Yilin Qu
Summary: This paper investigates the mechanically induced electric potential and charge redistribution in a piezoelectric semiconductor cylindrical shell. The results show that doping levels can affect the electric potentials and mechanical displacements, and alter the peak position of the zeroth-order electric potential. The doping level also has an inhibiting effect on the first natural frequency. These findings are crucial for optimizing the design and performance of cylindrical shell-shaped sensors and energy harvesters.
APPLIED MATHEMATICAL MODELLING
(2024)