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In order to study the laws of surface subsidence due to mining coal under thick alluvium of Quandian mine, two survey lines were designed on the surface above the first face. By analyzing the position of the maximum subsidence point of the tendency survey line, the zenith angle was obtained, and the correctness of taking bedrock thickness instead of average mining depth to design the position of the trend survey line in the mining area was confirmed; and based on the analyses of the measured data, the critical size of the gob full opening in the geological and mining conditions didn't follow the general law that the gob would reach the critical size when the panel has moved for a distance of 1.2H₀ - 1.4H₀. These results showed that the bedrock played a major role in the spread of whole overburden subsidence in the geological and mining conditions, while the loose layer had less affection. In addition, based on the analyses of the measured data, some rock movement parameters and probability integral prediction parameters of the surface subsidence of Quandian mine in the geological and mining conditions have been obtained. The study would have some important theoretical significance and practical guidance for implementing mining beneath buildings, water bodies and railways and prevent of this coal field as well as surface structure damage control.

Significant numbers of business process management (BPM) projects fail. Their failure is attributed toward many factors. Among them, low quality of BPM is one reason. Some of the tasks in BPM have their roots in business process reengineering (BPR). The literature has cited many different critical success and failure factors for quality BPM and BPR. Lack of software tools is one of the technology-oriented factors that results in poor BPM and BPR. This paper aims to build a generic feature set offered by software tools for process modeling their analysis implementation and management. It presents an objective analysis in identifying weaknesses and strengths of these tools, primarily for BPM.

A method is proposed to evaluate the quality of process reengineering and management delivered by software tools. It consists of four phases: feature extraction, tool selection, data extraction and tool evaluation.

The data gathered is quantified to test research hypotheses, the results are statistically significant and highlight multiple areas for future improvements. Moreover, the cluster visualizations created also help to understand the strengths and weaknesses of BPM/BPR tools.

Despite the research approach used, there is a chance of subjectivity when it comes to evaluating different tools.

The paper includes implications for practitioners and researchers for choosing appropriate software tool for process modeling, analysis, implementation and management, matching their requirements with BPM and BPR. It also identifies features that are missing in these tools.

This paper provides a comprehensive analysis of BPM and supporting tools, relates them to key stages of BPM life cycle and BPR methodologies. It also identifies various areas for further development in these tools.

The paper seeks to develop a stereo vision system based on a new binocular device. It aims to present an explicit‐implicit correction method to correct radial and tangential distortion of image synchronously. It also aims to propose a step‐rotation rectification method to rectify epipolar error between stereo pairs.

Least squares technique was used in solving the explicit‐implicit correction model. When the step‐rotation rectification method was implemented, the technology of rotating image space was used.

The paper finds that the stereo vision system based on a new binocular device can be used in different circumstances, and it can obtain more eyeshot of cameras. The explicit‐implicit correction method can eliminate radial and tangential distortion of images, and the solution to this method is so easy that it can be solved by least squares technique. The theory of step‐rotation rectification is simple, and it is effective for rectifying epipolar error.

The explicit‐implicit correction method and step‐rotation rectification method can be used in correcting image distortion and epipolar error in stereo pairs collected by a stereo vision system. The new binocular device can be used in building a stereo vision system.

A new binocular device is developed in the paper. Explicit distortion method and implicit distortion method are united to correct image distortion. A step‐rotation rectification method is proposed to rectify epipolar error.

Cloud computing services gained huge attention in recent years and many organizations started moving their business data traditional server to the cloud storage providers. However, increased data storage introduces challenges like inefficient usage of resources in the cloud storage, in order to meet the demands of users and maintain the service level agreement with the clients, the cloud server has to allocate the physical machine to the virtual machines as requested, but the random resource allocations procedures lead to inefficient utilization of resources.

This thesis focuses on resource allocation for reasonable utilization of resources. The overall framework comprises of cloudlets, broker, cloud information system, virtual machines, virtual machine manager, and data center. Existing first fit and best fit algorithms consider the minimization of the number of bins but do not consider leftover bins.

The proposed algorithm effectively utilizes the resources compared to first, best and worst fit algorithms. The effect of this utilization efficiency can be seen in metrics where central processing unit (CPU), bandwidth (BW), random access memory (RAM) and power consumption outperformed very well than other algorithms by saving 15 kHz of CPU, 92.6kbps of BW, 6GB of RAM and saved 3kW of power compared to first and best fit algorithms.

The proposed multi-objective bin packing algorithm is better for packing VMs on physical servers in order to better utilize different parameters such as memory availability, CPU speed, power and bandwidth availability in the physical machine.

Explores the changing relationship between work and leisure with particular reference to women’s equality in economic and other activities through a review of the history of leisure opportunities since the industrial revolution; indicates the ways in which social and economic changes have had a major impact on women’s leisure needs and activities. Focuses in particular on the provision of workplace fitness facilities, undertaking a survey of more than 200 companies across a number of industry sectors (the rationale for selection is outlined here) to discover the reasons behind such provision and the actual facilities provided; identifies the reasons behind provision as primarily commercial (e.g. being seen as an additional benefit to help recruit high quality employees) and notes that assessment of user group needs was not carried out, with the result that women’s particular needs tended not to be taken into account, for example gyms (favoured by men) being more widely provided than space for aerobic exercise (favoured by women). Concludes that the findings strongly suggest that women remain unequal in their leisure as well as working lives.

This study aims to provide a fresh look at banks as lenders in and extending past the COVID-19 crisis, with a particular focus on examining the results of recent work by Lei et al. (2020).

The authors’ replication, as well as the original paper, uses a fixed-effects model on panel data. The authors discuss issues regarding data sources as well as use an array of panel data robustness checks to help ascertain an appropriate empirical specification for continued research of this type.

The authors show that the results of Lei et al. (2020) are sensitive to the data source, as well as the construction of the standard errors in their regression framework, with an appropriate specification uncovered through panel data statistical tests. The authors also provide some extensions to the original work by including interacted fixed-effects models and extending the sample period from 2020Q1 to 2021Q1, noting some changes in results.

The authors provide novel results on banks’ lending constraints both at the onset of the COVID-19 pandemic and shortly thereafter. The study also provides an empirical framework for future studies conducted on similar panel data sets.

This study aims to investigate the microtopography transformation at a low-speed heavy-load interface with the lubrication of powder particles and its nonlinear friction effect on the sliding pair in contact.

Based on the universal mechanical tester (UMT) tribometer and VK shape-measuring laser microscope, comparative friction experiments were conducted with graphite powder lubrication. The friction coefficient with nonlinear fluctuations and the three-dimensional morphology of the boundary layer at the interface were observed and analyzed under different operating conditions. The effects on lubrication mechanisms and frictional nonlinearity at the sliding pair were focused on under different surface roughness and powder layer thickness conditions.

At a certain external load and sliding speed, the initial specimen surface with an appropriate initial roughness and powder thickness can store and bond the powder lubricant to form a boundary film readily. The relatively flat and firm boundary layer of powder at the microscopic interface can reduce the coefficient of friction and suppress its nonlinear fluctuation effectively. Therefore, proper surface roughness and powder layer thickness are beneficial to the graphite lubrication and stability maintenance of a friction pair.

This research is conducive to developing a deep understanding of the microtopography transformation with frictional nonlinearity at a low-speed heavy-load interface with graphite powder lubrication.

The ongoing urbanization and decarbonization require deployment of energy storage in the urban energy system to integrate large-scale variable renewable energy (VRE) into the power grids. The cost reductions of batteries enable private entities to invest energy storage for energy management whose operating strategy may differ from traditional storage facilities. This study aims to investigate the impacts of energy storage on the power system with different operation strategies. Two strategies are modeled through a simulation-based regional economic power dispatch model. The profit-oriented strategy denotes the storage system operated by private entities for price arbitrage, and the nonprofit-oriented strategy denotes the storage system dispatched by an independent system operator (ISO) for the whole power system optimization. A case study of Jiangsu, China is conducted. The results show that the profit-oriented strategy only has a very limited impact on the cost reductions of power system and may even increase the cost for consumers. While nonprofit-oriented energy storage performs a positive effect on the system cost reduction. CO₂ emission reduction can only be achieved under a high VRE scenario for energy storage. Integrating energy storage into the power system may increase CO₂ emissions in the near term. In addition, the peak-valley spread is crucial to trigger operations of profit-oriented energy storage, and the profitability of energy storage operator is observed to be decreasing with the total storage capacity. This study provides new insights for the energy management in the smart city, and the modeling framework can be applied to regions with different resource endowments.

The authors characterize two battery storage operating strategies of profit- and nonprofit-oriented by adopting a simulation-based economic dispatch model. A simulation from 36 years of hourly weather data of wind and solar output from case study of Jiangsu, China is conducted.

The results show that the profit-oriented strategy only has a very limited impact on the cost reductions of power system and may even increase the cost for consumers. While nonprofit-oriented energy storage performs a positive effect on the system cost reduction. CO₂ emission reduction can only be achieved under high VRE scenario for energy storage. Integrating energy storage into the power system may increase CO₂ emissions in the near term. In addition, the peak-valley spread is crucial to trigger operations of profit-oriented energy storage, and the profitability of energy storage operator is observed to be decreasing with the total storage capacity.

This study provides new insights for the energy management in the smart city, and the modeling framework can be applied to regions with different resource endowments.

This study aims to test the experiential advantage argument from both the hedonic and eudaimonic well-being perspectives and seeks to explore the mediating roles of a sense of meaning, as well as the moderating effects of consumers’ motivational autonomy, in a novel context – China.

Study 1 (n = 203) used a between-subject experiment where participants role-played an imaginary purchase with experiential versus material focus; Study 2 (n = 290) used a recall method where participants were asked to recall their past experiential purchase or material purchase that cost more than RMB500 (about US$70); Study 3 (n = 185) used a between-subject experiment where participants were assigned to one of the four scenarios (two types of purchases (experiential vs material) × 2 levels of motivational autonomy (high vs low).

The authors find that the experiential advantage argument holds true for eudaimonic well-being as well as hedonic well-being in three studies with Chinese consumers. In addition, the authors find that a sense of meaning serves as an additional mediator for the experiential advantage argument. Further, the authors find that the level of motivational autonomy positively moderates the effect size of experiential advantages and the mediating roles of a sense of meaning.

The authors only address the two ends of the experiential–material purchase continuum. Whether the discovered mediation roles of a sense of meaning and the moderation roles of motivational autonomy hold for hybrid experiential products remain unknown.

The authors enriched the experiential advantage literature through exploring the mediation roles of a sense of meaning and the moderating effects of motivational autonomy in the experiential advantage model.