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1 – 10 of 20Zhimin Liang, Xinyu Zhao, Yunjia Li, Yuzhong Rao, Kehong Wang and Xiaobing Wang
Adding Pd element to Au wire can improve the reliability of Au-Al bonding, but the mechanism of Pd element has not been well revealed so far. The purpose of this study is to…
Abstract
Purpose
Adding Pd element to Au wire can improve the reliability of Au-Al bonding, but the mechanism of Pd element has not been well revealed so far. The purpose of this study is to reveal in more detail the mechanism of the role of Pd elements in Au/Al bonding.
Design/methodology/approach
In this paper, the microstructure changes and tensile data of 99.99% (4N) gold wire and 99% (2N) gold wire with 1 at % Pd were compared through high-temperature thermal aging treatment of the specimens, so as to explore the influence mechanism of Pd element on Au-Al bonding reliability.
Findings
The addition of Pd element effectively reduces the thickness of intermetallic compounds (IMCs) layer and strengthens the fracture tension and reliability. Compared with the 4N specimen, the average thickness of the IMCs layer of the 2N specimen under the same conditions is reduced by 1 µm, and the tensile value of the 2N specimen is increased by 1−3 g. Stored at 200°C for 200 h, the failure rate of bond point of 4N specimen reached 94.64%, and that of 2N specimen was 20%, with a difference of 4.73 times.
Originality/value
Through comparative analysis of the data, this study found that the doping of Pd element in Au-Al IMCs in the early stage slowed down the growth rate of the IMCs, and the precipitation of Pd element in the late stage to form a better Pd-rich layer hindered the element mutual diffusion behavior between Au and Al.
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Yong Zha, Xixiang Ding, Liang Liang and Zhimin Huang
With rapid social development and deepening division of labor, more and more complex projects are required to be carried out in a team form. When evaluating team performance…
Abstract
With rapid social development and deepening division of labor, more and more complex projects are required to be carried out in a team form. When evaluating team performance, previous research has usually treated team as a united entity. However, the operating environment of the team has a significant impact on its members and the interaction between them greatly influences the team's efficiency. To better evaluate team performance, we propose a circle loop to illustrate the relationship between the operating environment of the team and its members. A two-stage DEA model with feedback is developed to evaluate the team performance, together with the efficiencies of the operating environment and team members as well as their impacts on overall efficiency. Various conditions of the team are discussed to illustrate that team performance depends on the assumption of the conditions.
Feng Yang, Qianqian Yuan, Zhimin Huang and Liang Liang
The current chapter is a tentative step toward investigating the allocation of advertising budget between the internet platform and the entity platform according to the long-term…
Abstract
The current chapter is a tentative step toward investigating the allocation of advertising budget between the internet platform and the entity platform according to the long-term and short-term achievement of advertising investment. We provide a decision-making framework on how to allocate the advertising budget to the two platforms for the best results. The integrated effect of advertising investment consists of two parts. Goodwill and customer scale reflect the long-term achievement, and sale profit represents the short-term achievement. We selected some representative feasible investment plans as decision-making units (DMUs), and calculated the values of sale profit, goodwill, and customer scale as three outputs. To determine the best advertising investment plan, we use data envelopment analysis (DEA) model to seek efficient plans, and then determine the best one from those efficient plans through preference investigation and super-efficiency technique.
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Feng Yang, Yanfang Yuan, Liang Liang and Zhimin Huang
The study on output allocative efficiency considering the emission trading is meaningful to allocate emission quota in order to promote production efficiency of industry. This…
Abstract
The study on output allocative efficiency considering the emission trading is meaningful to allocate emission quota in order to promote production efficiency of industry. This chapter studies the output allocation problem with constraints to profit and pollution goals, and proposes three types of output allocative efficiency measures, including the comprehensive output allocative efficiency, the profit-oriented output allocative efficiency based on pollution constraint, and the pollution-oriented output allocative efficiency based on profit constraint, which aim to maximize the total profit and (or) minimize the total pollution. The proposed measures are used to evaluate the output allocative efficiencies of 32 paper mills along the Huai River in China, and different parameters are tested with sensitivity analysis to examine the changes of optimal output combination. This chapter helps the enterprise to optimize the decision of production and helps the government to formulate a reasonable plan of pollution control and treatment.
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Yi He, Qinglong Gou, Liang Liang, Zhimin Huang and Rakesh Gupta
In today's world, all firms’ corporate social responsibility (CSR) actions are coming under increasing public scrutiny. This is especially true for large companies whose decisions…
Abstract
In today's world, all firms’ corporate social responsibility (CSR) actions are coming under increasing public scrutiny. This is especially true for large companies whose decisions can and do have impact on society. Public service advertisements (PSAs), a mass-media approach, are advertisements which inform audiences of a firm's CSR actions and enhance its public image. In this chapter, we focus on a supply chain system consisting of two firms and their coordination strategy for public service advertising. To describe the synergistic effect between a PSA and a normal commercial advertisement, a modified Nerlove–Arrow model is employed in this chapter. Using differential game theory, we calculate and compare the optimal advertising levels for each stage of the supply chain system under two different decision scenarios, i.e., (i) the two firms make decisions independently and (ii) the two firms make decisions as an integral system. A coordination mechanism on the public service advertising between the two firms has also been proposed for the supply chain system and has been proved effective.
Yong Zha, Liang Liang, Jie Wu and Zhimin Huang
As a Data Envelopment Analysis (DEA) extension tool, cross-evaluation method was developed to evaluate Decision Making Units’ (DMUs) performances in a competitive situation with…
Abstract
As a Data Envelopment Analysis (DEA) extension tool, cross-evaluation method was developed to evaluate Decision Making Units’ (DMUs) performances in a competitive situation with limited demand. It identifies DMUs with best performances and rank them by applying peer evaluation mode instead of self-evaluation mode. However, it has limitations in efficiency improvement. That is, it fails to give direct information on how to improve efficiencies of the inefficient DMUs. In this chapter, we propose an alternative way to apply cross-evaluation in efficiency improvement. First, an appropriate and feasible suggestion is proposed to minimize the variation between the weights of a DMU's own optimal Charnes-Cooper-Rhodes (CCR) efficiency and the weights guaranteeing its cross-efficiency score. We exploit several transformations to convert nonlinear programming into a linear one. As a result, an overall optimal set of the weights is obtained, which precisely illustrate the preferences of decision makers and exact characteristics of production process of the evaluated DMU. A further discussion is advanced to examine the existence of non-uniqueness of the weights and to differentiate various sets of the optimal weights by suggesting a unique feasible set of multipliers to best represent the alternative weights selection criterion. Moreover, we develop several models to reallocate the inputs and outputs of inefficient DMUs with minimum amelioration as well as consideration of the preference of decision makers. Finally, we apply our models to evaluate competitive advantages of Chinese cities.
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Peiyu Wang, Qian Zhang, Zhimin Li, Fang Wang and Ying Shi
The study aims to devise a comprehensive evaluation model (CEM) for evaluating spatial equity in the layout of elderly service facilities (ESFs) to address the inequity in the…
Abstract
Purpose
The study aims to devise a comprehensive evaluation model (CEM) for evaluating spatial equity in the layout of elderly service facilities (ESFs) to address the inequity in the layout of ESFs within city center communities characterized by limited land resources and a dense elderly population.
Design/methodology/approach
The CEM incorporates a suite of analytical tools, including accessibility assessment, Lorenz curve and Gini coefficient evaluations and spatial autocorrelation analysis. Utilizing this model, the study scrutinized the distributional equity of three distinct categories of ESFs in the city center of Xi’an and proposed targeted optimization strategies.
Findings
The findings reveal that (1) there are disparities in ESFs’ accessibility among different categories and communities, manifesting a distinct center (high) and periphery (low) distribution pattern; (2) there exists inequality in ESFs distribution, with nearly 50% of older adults accessing only 18% of elderly services, and these inequalities are more pronounced in urban areas with lower accessibility, and (3) approximately 14.7% of communities experience a supply-demand disequilibrium, with demand surpassing supply as a predominant issue in the ongoing development of ESFs.
Originality/value
The CEM formulated in this study offers policymakers, urban planners and service providers a scientific foundation and guidance for decision-making or policy amendment by promptly assessing and pinpointing areas of spatial inequity in ESFs and identifying deficiencies in their development.
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Ran Pan, Qinglong Gou and Zhimin Huang
In this chapter, we investigate whether the option contract can coordinate a supply chain when supply chain members have fairness concerns. Specifically, we consider a supply…
Abstract
In this chapter, we investigate whether the option contract can coordinate a supply chain when supply chain members have fairness concerns. Specifically, we consider a supply chain consisting of a manufacturer and a retailer where the two members can be either rational or fair-minded, and explore the condition under which the supply chain can be coordinated using an option contract. We follow the traditional newsvendor model by assuming that the market demand is stochastic with a cumulative distribution function and the retail price is exogenous. Under the option contract, the manufacturer’s decision variables include its option price and its exercise price, and the retailer is to decide its order quantity. We derive the equilibrium results for four different scenarios, that is, (i) both the two members are rational, (ii) the supplier is rational but the retailer is fair-minded, (iii) the supplier is fair-minded but the retailer is rational, and (iv) both are fair-minded. While the option contract can coordinate the supply chain when either of the two members is rational, we also find that when both the two members are rational, the option contract can coordinate the supply chain only under some specific conditions. Furthermore, we investigate whether the two members will suffer the disadvantageous or the advantageous inequality in the equilibrium and find some interesting findings.
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Feng Yang, Xue Li and Zhimin Huang
In an omnichannel environment, customers switch channels from product discovery to eventual purchase decision strategically. Hence, the biggest challenge for retailers nowadays is…
Abstract
In an omnichannel environment, customers switch channels from product discovery to eventual purchase decision strategically. Hence, the biggest challenge for retailers nowadays is how to operate an effective omnichannel strategy. To improve inventory operational efficiency, this chapter investigates the influences of price setting and customers’ return probability on inventory forecasting. Subsequently, we explore how retailers participate in providing appropriate information delivery and product fulfillment. Specifically, a stylized newsvendor model, which incorporates customers’ showrooming behavior, is developed to address retailers’ inventory problem. Furthermore, we compare the benefits of buy-online-and-pick-up-in-store (BOPS) and showroom strategy which originates offline but is completed online. Three main findings are obtained as follows: (1)online and offline inventory order quantities augment with the ascending of pricing offline and online, respectively. Meanwhile, the inventory decisions increase when customers’ return probability declines; (2) the implementation of showroom helps retailers expand their pure online market coverage than BOPS, while it reduces the total inventory quantity if the proposition of unit online inventory cost accounting for product price exceeds physical store; and (3) showroom strategy is more profitable than BOPS option as long as unit online inventory cost is small enough. In addition, we find this boundary where showroom increases total profit expands with the attenuating of return probability.
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Dangshu Wang, Menghu Chang, Licong Zhao, Yuxuan Yang and Zhimin Guan
This study aims to regarding the application of traditional pulse frequency modulation control full-bridge LLC resonant converters in wide output voltage fields such as on-board…
Abstract
Purpose
This study aims to regarding the application of traditional pulse frequency modulation control full-bridge LLC resonant converters in wide output voltage fields such as on-board chargers, there are issues with wide frequency adjustment ranges and low conversion efficiency.
Design/methodology/approach
To address these issues, this paper proposes a fixed-frequency pulse width modulation (PWM) control strategy for a full-bridge LLC resonant converter, which adjusts the gain by adjusting the duty cycle of the switches. In the full-bridge LLC converter, the two switches of the lower bridge arm are controlled by a fixed-frequency and fixed duty cycle, with their switching frequency equal to the resonant frequency, whereas the two switches of the upper bridge arm are controlled by a fixed-frequency PWM to adjust the output voltage. The operation modes of the converter are analyzed in detail, and a mathematical model of the converter is established. The gain characteristics of the converter under the fixed-frequency PWM control strategy are deeply analyzed, and the conditions for implementing zero-voltage switching (ZVS) soft switching in the converter are also analyzed in detail. The use of fixed-frequency PWM control simplifies the design of resonant parameters, and the fixed-frequency control is conducive to the design of magnetic components.
Findings
According to the fixed-frequency PWM control strategy proposed in this paper, the correctness of the control strategy is verified through simulation and the development and testing of a 500-W experimental prototype. Test results show that the primary side switches of the converter achieve ZVS and the secondary side rectifier diodes achieve zero-current switching, effectively reducing the switching losses of the converter. In addition, the control strategy reduces the reactive circulating current of the converter, and the peak efficiency of the experimental prototype can reach 95.2%.
Originality/value
The feasibility of the fixed-frequency PWM control strategy was verified through experiments, which has significant implications for improving the efficiency of the converter and simplifying the design of resonant parameters and magnetic components in wide output voltage fields such as on-board chargers.
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