Zhi-Hai Zhang

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Verified

Zhi-Hai verified their affiliation via an institutional email.

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• PhD
• Professor (Associate) at Tsinghua University

This paper focuses on the scheduling problem of a new charging service model called valet charging service. In this service model, the service provider sends staff to charge electric vehicles for customers to reduce their range anxiety. When the calls for valet charging service are on a scale, the charging station designation and routing plan for s...

Real-time production monitoring incorporating progress prediction and anomaly detection is essential for quality and efficiency. Traditional vision-based anomaly detection methods struggle to differentiate between production-related features and background noise, and fail to consider the heterogeneity of production stages. This paper introduces an...

The paper presents a framework for addressing the single-period inventory control problem with substitutable resources. It introduces an end-to-end approach to determine inventory levels of multiple resource grades to meet stochastic demand at reduced costs. This framework is applicable to various scenarios such as multi-grade resource order decisi...

Overfitting commonly occurs when applying deep neural networks (DNNs) on small-scale datasets, where DNNs do not generalize well from existing data to unseen data. The main reason resulting in overfitting is that small-scale datasets cannot reflect the situations of the real world. Label smoothing (LS) is an effective regularization method to preve...

This paper focuses on the contextual optimization problem where a decision is subject to some uncertain parameters and covariates that have some predictive power on those parameters are available before the decision is made. More specifically, we focus on solving the Wasserstein-distance-based distributionally robust optimization (DRO) model for th...

In the realm of intelligent manufacturing, driven by the push towards smart factories and Industry 4.0, optimizing technology selection and sequencing is paramount for intelligent transformation. This complex decision-making process resembles a novel project selection and scheduling problem, characterized by Multiplicative Enhancement Effects (MEEs...

This article focuses on the social choice problem in which decisions are based on the utility of multiple stakeholder types. The sum of these utilities – Utilitarian welfare - is one of the most important objectives in solving the social choice problem. While it is the most efficient solution, maximizing Utilitarian welfare may lead to unfair outco...

Demand prediction to support appropriate production decisions is being actively studied. Many prediction models are designed to minimize the prediction error, which is measured by determining the difference between the predicted and ground-truth demand. However, these models ignore the effect of the prediction error on downstream production decisio...

To reduce substantial renewable energy spillage and satisfy the increase in green hydrogen demand in China, conversion of surplus renewable energy into hydrogen via electrolyzers has attracted increasing attention in recent years. Seasonal storages and interregional hydrogen supply chains are commonly employed to eliminate the inherent spatiotempor...

This paper addresses an integrated biomass pricing and logistics network design problem. A bilevel design and pricing model is proposed to capture the dynamic decision process between a biofuel producer as a Stackelberg leader and farmers as Stackelberg followers. The bilevel optimization model is transformed into a tractable single-level formulati...

This paper investigates the data-driven pricing newsvendor problem, which focuses on maximizing expected profit by deciding on inventory and pricing levels based on historical demand and feature data. We first build an approximate model by assigning weights to historical samples. However, due to decision-dependent effects, the resulting approximate...

We study the product design problem where a decision‐maker selects the features of a product from a set of feasible options. We focus on two widely studied objectives in this field, i.e., the share‐of‐choice (SOC) and buyers' welfare (BW). The two objectives are vulnerable to different kinds of customer preference misspecification, i.e., deviation...

p>Demand prediction to support appropriate production decisions is being actively studied. Many prediction models are designed to minimize the prediction error, which is measured by determining the difference between the predicted and ground-truth demand. However, these models ignore the effect of the prediction error on downstream production decis...

p>Demand prediction to support appropriate production decisions is being actively studied. Many prediction models are designed to minimize the prediction error, which is measured by determining the difference between the predicted and ground-truth demand. However, these models ignore the effect of the prediction error on downstream production decis...

Recently, market has witnessed a tremendous growth in E-commerce sales, which bring tons of opportunities as well as challenges. Warehouses have to handle unique characteristics of customer orders in the era of E-commerce which consists of small order scales, large items count, unexpected irregular order arrival patterns, seasonality demand peeks,...

In the preparedness phase of humanitarian logistics, uncertainties from both the supply and demand sides may dramatically increase morbidity and mortality. We consider a distributionally robust facility location model with chance constraints in which the nodes and edges of the network are vulnerable to random failure. Efficiency, effectiveness and...

This paper introduces a new charging service mode that is emerging in the market for electric vehicles called the valet charging service. Through this service mode, a company provides free valet charging services to users that are far away from charging stations, and users can request the fee-based service when they are unwilling to charge electric...

Customer satisfaction is a prevalent issue amongst manufacturing enterprises. Multi-agent scheduling models aim to optimise the given criteria for improving customer satisfaction by fulfilling the customisation requirements. An investigation is executed on a bi-agent flowshop scheduling model, where a mass of tasks maintained by two competitive age...

Closed-loop supply chains (CLSCs) have received considerable attention because of various economic and regulatory factors. A CLSC is characterized by more complicated network structures and higher uncertainties compared to traditional supply chain networks. Therefore, reliable CLSCs are being increasingly emphasized in academic circles due to the v...

The pricing and reverse logistics network design problem in remanufacturing has attracted considerable attention in recent years due to increasingly serious environmental problems. In this study, we consider a pricing and reverse logistics network design problem with price-dependent return quality uncertainty. To handle the high uncertainty in retu...

In this paper, a newsboy model is developed under uniformly distributed lead-time and demand that is an appropriate assumption in obtaining optimal relief inventory of humanitarian disasters; there is limited historical data on relief operations. Analytical and approximation solutions of optimal relief order quantity are derived. The effect of lead...

Disassembly scheduling has attained increasing attention in the academic community of reverse logistics. This paper studies a capacitated multi-item multi-period disassembly scheduling problem with parts commonality and random demand. The problem is formulated as a mixed integer nonlinear program (MINLP) with chance constraints. The objective funct...

Energy efficiency attains increasing attention in production systems due to growing energy costs and public perception of environmentally conscious operations. The paper features a capacitated production planning and scheduling problem (CPPS)with sequence-dependent setups for a continuous production line. Meanwhile, energy consumption costs associa...

An effective Emergency Medical Service (EMS) system can provide medical relief supplies for common emergencies (fire, accident, etc.) or large-scale disasters (earthquake, tsunami, bioterrorism attack, explosion, etc.) and decrease morbidity and mortality dramatically. This paper proposes a distributionally robust model for optimizing the location,...

The paper studies a generalized mixed-integer linear production planning problem with multi-period and multi-item specification in a make-to-order manufacturing system. In this system, a holding company assigns the customers’ orders to its subsidiary companies in a way to minimize the total cost as well as minimizing the maximal production utilizat...

Our partnering firm is a Chinese manufacturer of multimedia products that needs guidance developing its imminent closed-loop supply chain (CLSC). To study this problem, we take into account location, inventory, and testing decisions in a CLSC setting with stochastic demands of new and time-sensitive returned products. Our analysis pays particular a...

Photovoltaic (PV) power is one of the rapidly growing solar energy technologies worldwide. The Installed PV power capacity has considerably increased over the past decades. Consequently, the End-of-Life (EoL) management of used PV modules is becoming very urgent. This paper investigates strategic recycling network planning for recycling PV module c...

The cannibalization effect between new and remanufactured products impacts market demand and further influences supply chain design, which makes supply chain operations complex. This paper studies the impact of cannibalization between new and remanufactured products on supply chain network design and operations by considering a joint pricing-locati...

Many works in the area of Supply Chain Network Design (SCND) have integrated production costs as one lumped cost. However, production costs embody indirect (overhead) and direct costs. This work brings a model that integrates these two production costs along with inventory and transportation costs. In particular, the work looks at the tradeoff betw...

This study examines a capacitated disassembly scheduling and pricing problem, in which the disassembly yield of returned products depends on their acquisition prices. The problem is formulated as a non-convex mixed-integer program. The particle swarm optimization and dynamic programming are combined to address the problem in order to determine the...

With the growing anxiety over global warming, some groups have advocated the mandatory carbon labeling of products, whereas other groups have opposed such labeling. How consumers respond to carbon labels is a key question with important implications for both policy-makers and managers. Using a random nth-price auction experiment together with a que...

In a real-world assembly environment, the components of a product arrive at a plant over time. Works-in-process are assembled into end-products by following an identical processing route. When a worker at a particular stage repeatedly handles similar tasks and gains the knowledge to execute a task efficiently, the processing time for later tasks is...

The disassembly process in remanufacturing has attracted increasing attention in recent years due to the high importance of environmental issues. The paper studies a capacitated single-item multi-period disassembly scheduling problem with random yields and demands in which procured, returned items (root items) are disassembled into components or pa...

In a dynamic flow shop scheduling model, each released job has to be executed on a set of machines in series following the identical route. The criterion of optimality, total k-power completion time (k ≥ 2) is addressed for this problem. Given its NP-hardness, a branch and bound (B&B) algorithm is designed to obtain the optimal solutions for small-...

This paper considers a coordinated location-inventory model under uncertain demands for a closed loop supply chain comprising of one plant, forward and reverse distribution centers, and retailers. The inventory of new and returned products is managed at forward and reverse distribution centers respectively through a periodic review policy. The prop...

A given number of jobs in an open shop scheduling environment must each be processed for given amounts of time on each of a given set of machines in an arbitrary sequence. This study aims to achieve a schedule that minimizes total weighted completion time. Owing to the strong NP-hardness of the problem, the weighted shortest processing time block (...

This study investigates the static and dynamic versions of the flexible open shop scheduling problem with the goal of minimizing makespan. The asymptotic optimality of the general dense scheduling (GDS) algorithm is proven by the boundedness hypothesis. For large-scale problems, the GDS-based heuristic algorithms are presented to accelerate converg...

This paper discusses the capacitated disassembly scheduling with parts commonality and start-up cost, which has broad applications in remanufacturing and many other production systems. The problem is formulated as a mixed-integer programming model. A Lagrangian heuristic is developed, where the lower bound problem reduces to a linear model, and the...

Supply chains with returned products are receiving increasing attention in the operations management community. The present paper studies a capacitated facility location model with bidirectional flows and a marginal value of time for returned products. The distribution system consists of a single supplier that provides one new product to a set of d...

Chinese manufacturing industries continue to impact the world economy. It is important to understand what is happening in China and the uniqueness of Chinese manufacturing industries. Manufacturing Productivity in China brings together a group of authors from academia and industry to give an industrial engineering micro viewpoint instead of an econ...

The paper proposes a novel probabilistic model with chance constraints for locating and sizing emergency medical service stations. In this model, the chance constraints are approximated as second-order cone constraints to overcome computational difficulties for practical applications. The proposed approximations associated with different estimation...

Coordination among supply chains has elicited considerable attention in both academia and industry. This paper investigates an integrated supply chain network design problem that involves the determination of the locations for distribution centers and the assignment of customers and suppliers to the corresponding distribution centers. The problem s...

This work addresses the large-scale crude oil scheduling problem of China's SINOPEC Maoming refinery that imports various types of crude oil from two terminals via bidirectional long-distance pipelines. We use a hierarchical decomposition approach to construct a two-stage model of the refinery operations. In the upper-level model, storage and charg...

This paper addresses an open-shop scheduling problem with the objective of minimising the total quadratic completion time. A solution approach based on Lagrangian relaxation is presented to handle small-scale problems. Additionally, optimal properties are determined for two special cases of this problem. Finally, numerous experiments demonstrate th...

The paper presents a bi-objective robust program to design a cost-responsiveness efficient emergency medical services (EMS) system under uncertainty. The proposed model simultaneously determines the location of EMS stations, the assignment of demand areas to EMS stations, and the number of EMS vehicles at each station to balance cost and responsive...

In this paper, we study a generalized production planning problem, that simultaneously investigates the two decisions that play critical roles in most firms, namely, production planning and order splitting and assignment. The problem takes into consideration the production time windows and capacities. We formulate the integrated problem as a linear...

This article investigates the criterion of minimizing total k-power completion time (TKCT) in flow shop and open shop scheduling. For these NP-hard problems, the asymptotic optimality of the shortest processing time-based algorithms is proven for a sufficiently large problem scale. To numerically evaluate the convergence of the algorithms, new lowe...

Demand and lead time uncertainties have significant effects on supply chain behaviour. In this paper, we present a singleproduct three-level multi-period supply chain with uncertain demands and lead times by using robust techniques to study the managerial insights of the supply chain inventory system under uncertainty. We formulate this problem as...

When allocating community-based health services for a geographically defined region, health planners are often faced with the serious conflict for improved health service and a limited budget. This paper extends the cost-based P-median location–allocation model (Daskin & Dean, 2005) to include a public service element and uses the non-inferior set...

This article investigates the open-shop scheduling problem with the optimal criterion of minimising the sum of quadratic completion times. For this NP-hard problem, the asymptotic optimality of the shortest processing time block (SPTB) heuristic is proven in the sense of limit. Moreover, three different improvements, namely, the job-insert scheme,...

This paper investigates the capacitated lot sizing problem in closed-loop supply chain considering setup costs, product returns, and remanufacturing. We formulate the problem as a mixed integer program and propose a Lagrangian relaxation-based solution approach. The resulting Lagrangian subproblems are then solved by polynomial time algorithms. Com...

The optimized landing sequence of fight is one of the good methods to decrease delay and improve service. Especially, the objectives are usually conflicting and contradictive when the air traffic controller (ATC) makes the decision. The landing sequence at the busy airports can be regarded as one machine scheduling problem with multi-objectives in...

This paper examines the allocation of yard cranes and blocks for yard activities in container terminals. In this paper, the yard cranes are confined to rail mounted gantry cranes (RMGC), which are characterized by the restricted traveling range on a pair of rails. Since RMGCs and yard blocks are tightly bound to each other, when allocating them, we...

Scheduling track lines at a marshalling station where the objective is to determine the maximal weighted number of trains on the track lines can be modeled as an interval scheduling problem: each job has a fixed starting and finishing time and can only be carried out by an arbitrarily given subset of machines. This scheduling problem is formulated...

This paper examines the allocation of berths and quay cranes for vessels arriving at container terminals. Previous work in this area has either ignored or deemphasized the coverage range limitations of quay cranes or imposed too loose or too rigid assumptions about whether quay cranes can be adjusted during loading and discharging, thus making the...

A web-based machining parameter selection system for agile turning has been developed. Using this system, the users can select adequate machine tools, cutters, and cutting parameters for the turning process. The users can also evaluate the machining performance by obtaining the turning force, power consumption, vibration status, and workpiece disto...

The plan of track lines is an important factor which influences the efficiency of marshaling station. When a train reaches the station, schedulers need to decide which track will be occupied by train and how long the train will stay at the track. The problem is NP-complete when the number of track and train are unfixed. After the mathematical model...

This paper addresses a multi-depot vehicle routing problem with partial customers not yet assigned to depots and each depot having fleet size constraint. An integrated mathematical model has been constructed with the objective of minimizing both the total required fleet size and overall traveling distance. To overcome the computation difficulty res...

This paper deals with a hump scheduling problem in marshalling station which can be described as one machine scheduling with two objectives: minimizing the number of tardy jobs; minimizing the maximal tardiness of all the jobs. A bi-ACO algorithm aiming to solve the problem is proposed and an external collection E(P) is designed to find the approxi...

In this paper, a method is proposed to optimize the fixture layout in the peripheral milling of a low-rigidity workpiece. Because the locators on the secondary locating surface directly influence the deformation of the workpiece in peripheral milling, this paper deals with the optimization of the number and positions of the locators on the secondar...

In order to optimize the positions of the locators in peripheral milling of a thin-walled workpiece, a finite element model along with an accurate cutting forces model is proposed in this paper. The finite element model takes into account the thickness variations of the workpiece in peripheral milling. The locators on the secondary locating surface...

This paper presents an improved approach to calibrate the cutting coefficients in an end-milling model. In order to predict end-milling forces, lots of simulative models are established. In order to use them, coefficients in the models, for example, cutting pressure constants etc., must firstly be calibrated experimentally, and simulative precision...

Machining process modeling, simulation and optimization is one of the kernel technologies for virtual manufacturing (VM). Optimization based on physical simulation (in contrast to geometrical simulation) will bring better control of a machining process, especially to a variant cutting process – a cutting process so complex that cutting parameters,...

Multi-axis machine tools can more accurately machine curved surfaces. An analytical model was developed to predict the end-milling forces for arc curved surfaces to provide more precise control of the machine tools. The milling cutter axis must be kept perpendicular to the work piece surface to accurately machine arc curved surfaces. The undeformed...

This paper investigates the cutting forces in peripheral milling of curved surfaces on the horizontal milling machine. An analytical model of cutting forces is presented. The effect of the workpiece curvature is taken into account in the model construction. Based on the relationship of differential cutting forces and chip load, the total cutting fo...

This paper presents a model for predicting the cutting forces for waved-edge milling cutters that are widely used in rough machining. The development of the model is based on the analysis of the complicated cutting edge of waved-edge cutter. According to the existing local cutting force model and from the relationship of local cutting force and chi...

This paper presents the development of an analytical model of cutting forces in peripheral milling of curved surfaces. The effect of the workpiece curvature is taken into account in the model construction. Based on the relationship of differential cutting forces and chip load, the total cutting forces are formulated by integration of the differenti...

The cutting forces and torques that occurred during milling were predicted by developing an analytical cutting model for end milling with helical multi-flute cutters. The milling torque is an important mechanical characteristic of the milling process. The relationship between the elemental cutting torque and the cutting force was used to develop an...

A new and emerging agile manufacturing paradigm is attracting an increasing amount of attention from both the academic and industrial communities. Agile manufacturing makes use of modern information technology to form virtual enterprises, which agilely respond to the changing market demands. In recent years, Web related technology improves greatly...