Search results

In order for a software system to better serve the user, it should be able to adjust its behavior according to the changing needs in the environment. Oftentimes, selecting a particular action may depend upon various non‐functional requirements (NFRs) such as safety, cost, and so on. In the past, the many possible alternatives for an adaptation action by and large have not been considered systematically and rationally, keeping various NFRs in mind, hence, resulting in low‐level of confidence that such an action is indeed a best possible one that is really desirable. The purpose of this paper is to present a goal‐oriented approach to select alternative(s) based on a particular contextual event, while considering important NFRs.

The paper proposes a goal‐oriented approach in which various NFRs are treated as softgoals to be satisficed and used in exploring, analyzing and selecting among possible adaptation alternatives, in consideration of the particular contextual event.

Without the goal‐oriented methodology, which offers an ontology enriched with the notion of goals for contextual information and also integrates rules for triggering adaptation, the authors feel, through their scenario study applied to their smart‐phone application, that some critical issues might not have been considered in building a usable, useful system.

The concepts introduced in this paper provide a systematic and rational approach to select adaptation alternative(s), considering NFRs along with detecting a contextual event.

The purpose of this case study is to test a moderated mediation model linking employees' perceived HRM practices to organizational citizenship behaviours (OCB) with perceived insider status as the mediator and emotional exhaustion as the moderator in a Chinese high-tech organization.

A sample of 417 Chinese employees were recruited from a large Chinese high-tech company to participate in a paper-and-pencil survey, and mediation and moderation were analysed using PROCESS macro for SPSS.

Perceived insider status partially mediates the relationship between perceived HRM practices and OCB, and emotional exhaustion moderates the relationship between perceived insider status and OCB such that the strength of the relationship is stronger in employees with low emotional exhaustion levels than in employees with high emotional exhaustion levels.

There is a need for organizations to promote the physical and psychological well-being of its employees in order to maximize the effectiveness of HRM practices.

This case study provides novel insights into how employees' perceived HRM practices elicit OCB and its boundary conditions in collectivistic cultures.

During the coronavirus disease 2019 (COVID-19) pandemic, ubiquitous social media has become a primary channel for information dissemination, social interactions and recreational activities. However, it remains unclear how social media usage influences nonpharmaceutical preventive behavior of individuals in response to the pandemic. This paper aims to explore the impacts of social media on COVID-19 preventive behaviors based on the theoretical lens of empowerment.

In this paper, survey data has been collected from 739 social media users in China to conduct structural equation modeling (SEM) analysis.

The results indicate that social media empowers individuals in terms of knowledge seeking, knowledge sharing, socializing and entertainment to promote preventive behaviors at the individual level by increasing each person's perception of collective efficacy and social cohesion. Meanwhile, social cohesion negatively impacts the relationship between collective efficacy and individual preventive behavior.

This study provides insights regarding the role of social media in crisis response and examines the role of collective beliefs in the influencing mechanism of social media. The results presented herein can be used to guide government agencies seeking to control the COVID-19 pandemic.

The aim of this paper is to develop a redundancy‐resolution (RR) algorithm to optimize the joint space trajectory of the six‐rotation‐axis industrial robot as performing arc‐welding tasks.

The rotation of the tool around its symmetry axis is clearly irrelevant to the view of the task to be accomplished besides some exceptional situations. When performed with a general 6‐degrees‐of‐freedom (DOF) manipulator, there exists one DOF of redundancy that remains. By taking advantage of the symmetry axis of the welding electrode, the authors decompose the required instantaneous twist of the electrode into two orthogonal components, one lying into the relevant task subspace and one into the redundant task subspace, respectively. Joint‐limits and singularity avoidance are considered as the optimization objectives.

The twist‐decomposition algorithm is able to optimize effectively the joint space trajectory. It has been tested and demonstrated in simulation.

A new RR algorithm is introduced for the six‐rotation‐axis industrial robot performing welding tasks. A new kinetostatic performance index is proposed on evaluating the kinematic quality of robotic postures. It can also be used in other applications like milling, deburing and many other tasks requiring less than 6‐DOF in tool frame.

The purpose of this paper is to explore the Chinese leader–follower interaction model in school cases considering followers’ effect at varying social distances.

This study uses a case study approach.

First, Chinese leader–follower interactions in school cases are flexible in practice. Second, within leader–follower flexible interactions, contradictory perceptions and field-of-work consciousness foster different behavior choices between leaders and followers. Third, perceptions concerning the proximity of leaders to followers are positively influenced in relation to hierarchical distinctions and negatively influenced owing to private connections. Finally, the perceived leader distance of leaders from followers further influences the contradictory perceptions and field-of-work consciousness of leaders and followers and positively influences the degree of flexible leader–follower interaction.

This study examined a single institution; hence, results may have been influenced by school-specific features and conditions. Future research should study more organizations to explore whether their unique characteristics and contexts could affect leader–follower interactions, thus providing more generalized and universally applicable conclusions.

First, this study proposed a leader–follower flexible interaction model in school cases and the concepts of field-of-work consciousness and contradictory perceptions, exploring the active effects of followers in the leadership process to offer guidance toward better understanding the leadership process. Second, it was found that private connections between leaders and followers, as well as hierarchical differences, influenced the perceptions of both leaders and followers concerning leader distance in a Chinese context, and the influence of leader distance on leader–follower interactions was also analyzed.

To improve the sustainable performance of the power supply chain system (PSCS), the Chinese government proposed a series of relevant policies and promoted the application of various technologies in the power industry. This study analyzes the sustainable performance and technology levels of PSCSs in various regions of China.

To quantify the technological heterogeneity between PSCSs, this study incorporates a meta-frontier into the performance evaluation model. To increase the performance of inefficient PSCSs, this study also proposes a series of performance improvement path indexes.

Empirical analysis of China's provincial PSCSs, using data from 2014 to 2017, has yielded several key findings. First, the average performance of PSCSs of all provinces in China is 0.7192, indicating that PSCSs in China have great potential for improvement. Second, independent of power generation subsystem (PGS) or power retail subsystem (PRS), regional differences affect the technological heterogeneity of PSCSs in China. Third, for PGS, the technological level of PSCSs in the eastern region displays a high level, while the management level can still be greatly improved. Fourth, only the PSCS of Beijing is best in both PGS and PRS. The two subsystems of the PSCSs in the other provinces are either insufficiently managed or technologically inadequate.

Compared with the traditional performance model, the model proposed in this study considers the technological heterogeneity between PSCSs. In addition, the path indexes proposed in this study clearly indicate an improvement direction and the specific improvement level for inefficient PSCSs.

This study aims to improve the tribological performance of Babbitt alloy under oil lubricant condition. Thus, the surface was treated into oleophobic state by modifying with low surface energy fluorosilane (1H,1H,2H,2H-perfluorodecyltriethoxysilane). It is believed that the oleophobic surface offered excellent wear resistance of Babbitt-based tribo-pairs.

By modifying the Babbitt alloy with low surface energy fluorosilane and measuring the oil contact angle, the wetting behavior was evaluated. Using Pin on Disk tribometer, the tribological properties of bare Babbitt and modified Babbitt were quantified. The samples after the friction test were characterized by scanning electron microscope (SEM) and the anti-wear performance was evaluated under dry and oil lubrication conditions.

Results showed that oil contact angle of modified Babbitt was109° which was tripled compared to that of prime surface, which indicates the oleophobic behavior was greatly improved. Under dry conditions, the friction coefficient of the modified surface with different load conditions is slightly lower than that of the bare surface, while the friction coefficient of the modified surface under lubrication conditions is significantly decreased compared to that of the bare surface. Interestingly, under low load and high load, the wear rate of the modified Babbitt alloy surface is only 1/4 and 1/3 of that of the bare surface, respectively.

The work proposed an effective method to improve the Babbitt tribological performances and will lighten future ideas for the Babbitt alloy bearing with high wear resistance, which is beneficial to improve the service life of sliding bearings and has huge promotion and application value in the manufacture of sliding bearings.

The purpose of this paper is to identify staff skills and competencies on which Chinese open universities should focus their professional development activities in order to enhance the quality of open and distance learning (ODL) in China.

Data were collected from surveys of 220 academic and academic-related Chinese staff, each of whom participated in one of seven 3-day Learning Design and Course Creation (LDCC) workshops at three large regional open universities in China between 2017 and 2019. The workshops were based on the UK Open University (UKOU) approach to learning design (LD) and course creation. Using content analysis methodology, textual responses were analysed and compared against the Instructional Design Competencies framework provided by the International Board of Standards for Training, Performance and Instruction (IBSTPI).

(1) Designing instructional interventions, (2) keeping up to date with design theories, (3) communicating in order to manage stakeholders, teams and projects were the main competencies identified from the participants responses. However, these three identified competencies differed in emphasis between the institutions that took part.

In Western higher education institutions (HEIs), LD has developed as an important approach to improving quality. A need has been identified for robust approaches to quality and professional development opportunities to enhance teaching and learning standards in open and distance learning (ODL) in China. This paper identifies and discusses specific LD skills and competencies that could be targeted to improve the quality of ODL in China.

The power industry is the pillar industry of the Chinese economy, and also a major carbon emitter. The performances of both the production and operation of the power industry are crucial for a harmonious development of society. This study proposes an improved data envelopment analysis (DEA) model to analyze the sustainable performance of China's power supply chain (PSC).

To analyze the sustainable performance of PSC systems in China's provincial regions, this study proposes a two-stage directional distance function (DDF) model. The proposed model not only considers the leader–follower game relationship between the power-generation system and the retail system, but also considers the factors that measure the sustainability level of the PSC.

The proposed model is applied to assess the sustainable performance of the PSCs of China's provincial regions. The findings are valuable and mainly include the following aspects: First, compared with other models, this study regards the intermediate variable of the power system as a freely disposable variable; therefore, the efficiency of the proposed model is more realistic. Second, the average efficiency of China's power retailing system is generally lower than the average efficiency of its power-generation system. Third, significant regional differences affect the power-generation efficiency, while the regional differences in power retail efficiency are not significant. The power-generation performances of PSCs in East China and Northeast China are generally higher than in other regions.

This study introduces the convex technique into a DEA model and thus proposes an improved two-stage DDF DEA model. In response to the game-theoretic inherent in power systems, this study also introduces the leader–follower game into the two-stage model. In addition to the theoretic novelty, all PSCs can be classified with this model. Moreover, specific recommendations for each type of PSCs are proposed based on the efficiency results, thus providing vital guidance for the practice.

Many manufacturing sites require precision assembly. Particularly, similar to cell phones, assembly at the sub-mm scale is not easy, even for humans. In addition, the system should assemble each part with adequate force and avoid breaking the circuits with excessive force. The purpose of this study is to assemble high precision components with relatively reasonable vision devices compared to previous studies.

This paper presents a vision-force guided precise assembly system using a force sensor and two charge coupled device (CCD) cameras without an expensive 3-dimensional (3D) sensor or computer-aided design model. The system accurately estimates 6 degrees-of-freedom (DOF) poses from a 2D image in real time and assembles parts with the proper force.

In this experiment, three connectors are assembled on a printed circuit board. This system obtains high accuracy under 1 mm and 1 degree error, which shows that this system is effective.

This is a new method for sub-mm assembly using only two CCD cameras and one force sensor.