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In this paper, we study partial identification of the distribution of treatment effects of a binary treatment for ideal randomized experiments, ideal randomized experiments with a known value of a dependence measure, and for data satisfying the selection-on-observables assumption, respectively. For ideal randomized experiments, (i) we propose nonparametric estimators of the sharp bounds on the distribution of treatment effects and construct asymptotically valid confidence sets for the distribution of treatment effects; (ii) we propose bias-corrected estimators of the sharp bounds on the distribution of treatment effects; and (iii) we investigate finite sample performances of the proposed confidence sets and the bias-corrected estimators via simulation.

Drawing on Herzberg's motivation-hygiene perspective, this study examines the factors affecting expatriate adjustment and the relationship between expatriate adjustment and subsidiary performance of emerging market multinational enterprises (EMNEs).

Using structural equation modeling, this study tests a proposed conceptual model based on a matched dataset collected from 38 EMNEs.

The findings reveal that perceived organizational support (POS) and family adjustment are positively associated with expatriate adjustment, while remuneration and job burnout have no significant relationships with expatriate adjustment. In addition, expatriate adjustment is positively associated with the foreign subsidiary performance of EMNEs.

This study contributes to expatriate adjustment research in the EMNE context by distinguishing motivators and hygiene factors in affecting the expatriates' attitudes toward international assignments. Empirical evidence of expatriate adjustment-subsidiary performance relationship also enriches the authors’ knowledge of EMNEs' expatriation practices.

Most academic libraries provide book recommendation services to enable readers to recommend books to the libraries. To facilitate decision-making in book acquisition, this study aimed to develop a method to determine the ranking of the recommended books based on the recommender network.

The recommender network was conducted to establish relationships among book recommenders and their similar readers by using circulation records. Furthermore, social computing techniques were used to evaluate the degree of representativeness of the recommenders and subsequently applied as a criterion to rank the recommended books. Empirical studies were performed to demonstrate the effectiveness of the proposed ranking system. The Spearman’s correlation coefficients between the proposed ranking system and the ranking obtained using reader circulation statistics were used as performance measure.

The ranking calculated using the proposed ranking mechanism was highly and moderately correlated to the ranking obtained using reader circulation statistics. The ranking of recommended books by the librarians was moderately and poorly correlated to the ranking calculated using reader circulation statistics.

The book recommender can be used to improve the accuracy of book recommendations.

This study is the first that considers the recommender network on library book acquisition. The results also show that the proposed ranking mechanism can facilitate effective book-acquisition decisions in libraries.

The purpose of this paper is to present a system that analyzes trustworthiness and ranks applications to improve the search experience.

The system adopts pointwise mutual information to calculate comment semantics. It examines subjective (signed opinions, anonymous opinions and star ratings) and objective factors (download numbers, reputation ratings) before filtering, ranking and displaying). The authors invited three experts to check three categories and compared the results using Spearman and two statistics.

A high correlation between the proposed system and the expert ranking system suggests that the system can act as decision support.

First, the authors have only tested the correlation between the proposed system and an expert ranking system; user satisfaction was not evaluated. The authors plan to conduct a later survey to gather user feedback. Second, the ranking system evaluates applications using fixed weights and disregards time. Therefore, in the future, the authors plan to enable their system to weight recent records over older ones.

User discussion forums, although helpful, have drawbacks. Not all reviews are trustworthy, and forums provide no filtering mechanisms to combat information overload. The solution to this is the authors’ system that crawls a forum, filters information, analyzes the trustworthiness of each comment and ranks the application for the user.

This paper develops a formula to analyze the trustworthiness of opinions, enabling the system to act as decision support when no professional advice is available.

The purpose of this paper is to report the findings of a study that examines the influence of leader–member exchange (LMX) on employees' turnover intention and presenteeism with the mediating role of perceived organizational support in the context of the semiconductor industry.

An empirical study based on a sample of 124 department managers and 241 team members in five high-tech companies in Taiwan. Structural equation modelling analysis was used for hypothesis testing.

The results reveal that perceived organization support significantly relates to employees' turnover intention and mediates the relationship between LMX and turnover intention. Additionally, employees' presenteeism is influenced by perceived LMX.

The results of the study are of high importance for high-tech companies, which continuously strive for innovation efficiency and sustainability. Managers and practitioners could benefit from better understanding regarding the importance of perceived organization support and LMX in affecting employee behaviours and company performance.

The present study finds a significant positive relationship between LMX and presenteeism, which is contrary to the previous research.

This paper aims to present a smooth transition adaptive hybrid impedance control for compliant connector assembly.

The dynamics of the manipulator is firstly presented with linear property. The controller used in connector assembly is inspired by human operation habits in similar tasks. The hybrid impedance control is adopted to apply force in the assembly direction and provide compliance in rest directions. The reference trajectory is implemented with an adaptive controller. Event-based switching strategy is conducted for a smooth transition from unconstrained to constrained space.

The method can ensure both ideal compliance behaviour with dynamic uncertainty and a smooth transition from unconstrained to constrained space. Also, the method can ensure compliant connector assembly with a good tolerance to the target estimation error.

The method can be applied in the connector assembly by “pushing” operation. The controller devotes efforts on force tracking and smooth transition, having potential applications in contact tasks in delicate environment.

As far as the authors know, the paper is original in providing a uniform controller for improving force and position control performance in both unconstrained and constrained space with dynamic uncertainty. The proposed controller can ensure a smooth transition by only adjusting parameters.

This study aims to understand how the assembly of rotating ring affects the axial forced vibration of gas face seals.

A three-mass kinematic model is established to investigate the axial movement of the rotating ring with bilateral constraints. The separation, collision and frictional sliding of the rotating ring in sleeve are discussed under rotor excitation. The effects of operating parameters and O-ring dynamic characteristics on the separation degree and film thickness disturbance are analyzed. A dimensionless axial characteristic force is defined to determine the critical conditions for the occurrence of separation. Several effective methods to eliminate the separation are proposed based on the adjustment of typical installation parameters.

Under rotor excitation, there may be two collisions between the rotating ring and the sleeve surfaces in one excitation period. This will cause self-excited vibration of the fluid film, increasing the risk of seal failure. The separation and collision can be prevented by increasing the equilibrium ratio, the installation radius of the O-ring on the outer surface of the rotating ring and the friction in the sleeve.

The results develop the modeling of multibody dynamics of gas face seals, enabling more accurate prediction of vibration characteristics.

The purpose of this paper is to forecast the future trend of Ghana’s total energy consumption (GTEC) using two grey models, which are GM(1,1) and the grey Verhulst model.

The paper employs the use of Even model GM(1,1) and the grey Verhulst model to forecast GTEC for the next five years. Since various models were used, the margin for error is minimal, hence resulting in a better choice for forecasting the future. The forecast reveals that the GTEC for the next five years will increase rapidly.

The results reveal that the models can be used accurately to predict the total energy consumption smoothly. This will aid the government of Ghana to take necessary measures such as transforming the economic development pattern and enhancing the energy utilization efficiency since future patterns of energy consumed can be predicted.

This research is meaningful to the government and all stakeholders in Ghana to help develop and appreciate the energy sector and its economic impact. This research is going to help government put in measures for efficient utilization of energy since results reveal an increase in energy consumption.

Research results could be used for development of the energy sector through managerial and economic decision making.

Ghana is a developing country and has great prospects in terms of boosting or resourcing its energy sector to meet future demands. The successfully explored models could aid the government of Ghana to formulate policies in the energy sector and generate future consumption plans.