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The purpose of this paper is to study the electrochemical properties of electrode material on activated carbon double layer capacitors. It also tries to develop a prediction model to evaluate pore size value.

Back-propagation neural network (BPNN) prediction model is used to evaluate pore size value. Also, an improved heuristic approach genetic algorithm (HAGA) is used to search for the optimal relationship between process parameters and electrochemical properties.

A three-layer ANN is found to be optimum with the architecture of three and six neurons in the first and second hidden layer and one neuron in output layer. The simulation results show that the optimized design model based on HAGA can get the suitable process parameters.

HAGA BPNN is proved to be a practical and efficient way for acquiring information and providing optimal parameters about the activated carbon double layer capacitor electrode material.

The submitted paper is mainly concerned with the cracking of blind and buried vias of printed circuit board (PCB) for smartphones which were encountered with abnormal display problems like scramble display or no display during service and had to be recalled.

To found out the root causes of this failure and dissolve this commercial dispute, comprehensive failure analysis was performed on the printed circuit board assemblies (PCBAs) and PCBs of the failed smartphone, such as macrograph and micrograph observation, chemical compositions analysis, thermal performance testing and blind via pull-off experiment, which finally helped to determine the causes. Besides that, the failure mechanisms were discussed in detail, and pertinent countermeasures were proposed point by point.

It was found that the PCB blind vias cracking was the main reason for the scramble display or no display of the smartphone, and the incomplete cleaning process before copper plating was the root cause of the blind vias cracking.

Achievement of this paper would not only help to provide the solid evidence for determining the responsibility of this commercial dispute but also lead to a better understanding of the failure mechanisms and prevention methods for similar failure cases of other advanced mobile phones.

Most failure analysis researches of PCBAs only focused on the unqualified products from manufacturing, while this paper addressed a failure analysis case of PCBAs products for smartphones from actual services, which was relatively rarely reported in the past.

Nitrogen oxides (NO_x) have been considered as primarily responsible for many serious environmental problems. Removing NO is the key task to remove NO_x hazards. To clarify, NO removal process for pitch-based spherical-activated carbons (PSACs), an online prediction and optimization technique in real-time based on support vector machine algorithm in regression (support vector regression [SVR]) is discussed. The purpose of this paper is to develop a predictor and optimizer system on selective catalytic reduction of NO (SCRN) using experimental data and data-driven SVR intelligence methods.

Predictor and optimizer using developed SVR have been proposed. To modify the training efficiency of SVR, the authors especially customize batch normalization and k-fold cross-validation techniques according to the unique characteristics of PSACs model.

The results present that SVR provides a property regression model since it can linkage linear and non-linear process and property relationships in few experimental data sets. Also, the integrated normalization and k-fold cross-validation show a satisfying improvement and results for SVR optimization. The predicted results of predictor and optimizer in single and double factor systems are in excellent agreement with the experimental data.

SCRN-PO for predicting and optimization SCRN problems is developed by data-driven methods. The outperformed SCRN-PO system is used to predict multiple-factors property parameters and obtain optimum technological parameters in real-time. Also, experiment duration is greatly shortened.

Although the importance of network embeddedness attracted much attention in recent years, the interpretations of the underlying mechanism almost focus on the positive effects and neglect the potential negative aspects. This paper aims to use Chinese listed manufacturing enterprises, in the perspective of network embeddedness, to analyze whether resource curse effects exist in strategic networks of enterprises.

This paper examines the resource curse effect that exists in enterprise networks through analysis of enterprise’s total factors productivity compared with those of its industry peers with different degrees of embeddedness. This paper then uses several different methods, such as clustered fixed and random effect model, core and peripheral model, and generalized method of moments estimation in endogenous checks, to detect network curse effects and reveal three potential mechanisms, including overinvestment, extra maintaining cost and innovation extrusion.

This paper finds that excessive network embeddedness hinders continuous improvement of productivity, which is derived from three mechanisms: excessive network embeddedness makes information redundancy among enterprises, and the imitate-follow effect makes excessive investment seriously; enterprises have to encounter more problems and difficulties, such as information coordination and benefit negotiation, to maintain network relationship, which leads to extra cost; enterprises with abundant network resources may tend to more emphasis on marketable operational abilities, resulting in resource decentralization and less investment on innovation, which is finally not beneficial to productivity improvement in the long run.

Compared with previous literatures, this paper not only enriches the understanding of negative mechanisms in enterprise`s network embeddedness, but also unfolds the inconsistency of network embeddedness effects in practice and finds new evidence that the two types of network embeddedness are consistent in certain circumstances.

In view of organizational inertia, with the occurrence of a major event, though resource rigidity minimizes, however simultaneously, it increases process rigidity, which creates difficulties in motivating managers and dealing with the agency problem. Therefore, keeping in mind the high demand created by the China–Pakistan Economic Corridor and Naya Pakistan Housing Scheme in the cement sector of Pakistan, the purpose of this paper is to investigate the impact of corporate governance (CG) on the cost of equity (COE) in the cement sector, to deal with the problems surging during and after the completion of these projects and highlight further opportunities for the cement sector of Pakistan.

CG is a qualitative concept therefore, eight proxies have been used to measure it along with the two control variables. This study uses balance panel data of six years from 2012 to 2017, collected from 18 companies of the cement sector of Pakistan. Descriptive statistics have been used to describe the data, correlation matrix to see the nature of the relationship, and Pooled OLS as the estimation technique, while to analyze the data a statistical package 13 has been used. To measure the COE, the Capital Asset Pricing Model (CAPM) has been used.

Regression results suggest that block ownership, insider ownership and the board size are insignificant, while CEO tenure is negatively and significantly associated with the COE. Non-executive directors, independence and CEO duality are insignificant; however, diversity is positively and significantly associated with the COE. Moreover, the mean value of the COE is 8.22 percent for the cement sector, while the coefficient of determination of the model under study is 74 percent.

This paper is based on the data from the cement sector of Pakistan only. Therefore, this is the reason that these results cannot be generalized on the whole economy of Pakistan.

This study helps in finding out the COE value specific to the cement sector, which will help this sector to evaluate the capital budgeting decision more precisely and accurately than before. Moreover, the association of diversity as positive, while independence as negative with the COE highlights a room for improvement in the implementation of CG codes by SECP. This study also helps to mitigate the impact of inertia, the after-effects of high demand, and managing the agency problem in the cement sector.

This is the first study using CG data collected just after the revised promulgation of CG codes in 2012, along with a wide range of eight proxies measuring CG and its impact on the COE in the cement sector.

This paper aims to investigate the impact of pay-for-performance (PFP) perception and pay level satisfaction on work attitudes (job satisfaction, turnover intention and affective commitment) and extra-role behaviors (discretionary effort and interpersonal helping), and further, how three aspects of conditional factors – intrinsic motivation, leader–member exchange (LMX) and perceived organizational support (POS) – moderate the main-effect relationships.

The study was conducted at a Chinese private-owned company in the beauty industry, and a survey was conducted with the frontline employees in each office, asking information about their perceptions and attitudes toward the PFP scheme implemented in the company, work attitudes and performance, individual characteristics and their perceptions of group and organizational characteristics.

Results show that PFP perception and pay level satisfaction are significant predictors of work attitudes and extra-role behaviors. Further, depending on the specific work outcome examined, the three conditioning factors are found to strengthen the hypothesized main-effect relationships. The findings of the study have important theoretical and practical implications for the implementation of PFP schemes in organizations.

The findings contribute to the scholarship on PFP schemes in two ways. First, the findings show that PFP perception and pay level satisfaction are important for understanding employee work attitudes and extra-role behaviors. Second, the investigation of the moderating roles that intrinsic motivation, LMX and POS play in the relationships of PFP perception and pay level satisfaction with the work outcomes provides evidence to the limited understanding about the conditions that may strengthen or weaken the effectiveness of PFP schemes.

Frictions in cylinder liner-piston ring often cause an inevitable loss of energy loss in the diesel engine. This study aims at evaluating the effect of depths in the cylinder liner groove texture on friction, wear and sealing performances.

Five depths of groove texture cylinder liners (50, 100, 150, 200, 250 µm) were fabricated, and experiments were carried out using a special-purpose diesel engine tester. Comparative analyses of cylinder liner contact resistances, piston ring wear losses and surface appearances were conducted with respect to different surface textures and applied loads.

Under no-load conditions, the cylinder liner with a 100 deep thread groove can significantly improve sealing and optimize its lubrication performance. On the other hand, the sealing is highly correlated with the depth of groove and the load within the cylinder liner. Under loaded conditions, the thread groove has less effect on the sealing performance.

The findings can provide feasible basis for the tribological design and production of diesel engines.

The purpose of this investigation is to identify, evaluate, integrate and summarize relevant and qualified papers through conducting a systematic literature review (SLR) on the application of recommender systems (RSs) to suggest a scholarly publication venue for researcher's paper.

To identify the relevant papers published up to August 11, 2018, an SLR study on four databases (Scopus, Web of Science, IEEE Xplore and ScienceDirect) was conducted. We pursued the guidelines presented by Kitchenham and Charters (2007) for performing SLRs in software engineering. The papers were analyzed based on data sources, RSs classes, techniques/methods/algorithms, datasets, evaluation methodologies and metrics, as well as future directions.

A total of 32 papers were identified. The most data sources exploited in these papers were textual (title/abstract/keywords) and co-authorship data. The RS classes in the selected papers were almost equally used. DBLP was the main dataset utilized. Cosine similarity, social network analysis (SNA) and term frequency–inverse document frequency (TF–IDF) algorithm were frequently used. In terms of evaluation methodologies, 24 papers applied only offline evaluations. Furthermore, precision, accuracy and recall metrics were the popular performance metrics. In the reviewed papers, “use more datasets” and “new algorithms” were frequently mentioned in the future work part as well as conclusions.

Given that a review study has not been conducted in this area, this paper can provide an insight into the current status in this area and may also contribute to future research in this field.

The purpose of this paper is to set out a study of a Mannich base, which was synthesized and used as an acidizing corrosion inhibitor first, and to the corrosion inhibitor mechanism.

A Mannich base, 1-phenyl-3-(1-pyrrolidinyl)-propanone (PHPP), was synthesized with acetophenone, pyrrolidine and formaldehyde at pH = approximately 2-3. The structure of PHPP was characterized by elemental analysis and Fourier transform infrared spectroscopy (FTIR). The corrosion inhibition of PHPP on N80 steel in 15 per cent hydrochloric acid (HCl) was studied by weight loss method, scanning electron microscope (SEM) and energy dispersive X-ray analysis (EDAX), and the adsorption behavior of PHPP on the surface of N80 steel was discussed.

The results showed that the inhibition efficiency reached to 99.8 per cent and corrosion rate was 2.65 g·m-2·h-1 at 0.6 per cent of PHPP concentration in 15 per cent HCl, which indicated that PHPP presented excellent corrosion inhibition performance. The results of SEM and EDAX analysis showed that PHPP could be absorbed on the surface of N80 steel. The adsorption process of PHPP on the surface of N80 steel was chemisorption. This process was spontaneous and obeyed Langmuir adsorption isotherm.

It was found that PHPP presented excellent corrosion inhibition performance, and it is practicable to enhance oil production in oilfield development as a oil-well acidizing inhibitor. The study results can provide theoretical guidelines for the development of the inhibitor.

The purpose of this paper is to develop a portable all‐position welding robot for the welding of intersected pipes.

A complete procedure is adopted to conduct the design. The task and motion of the robot are analyzed and a mathematical description of the pose and position of the welding tool is given. Based on that, three representative types of robot are chosen in the type synthesis of mechanism. Two new indices proposed to evaluate required properties of the robot, along with the traditional dexterity index, are chosen to be the criteria in the dimension synthesis of mechanism. Through the optimization by genetic algorithm, the best robot in type and dimension is determined after comparison on their performances. Finally, the prototype is developed.

The paper finds a new robot for welding intersected pipes.

A new robot is introduced for the welding of intersected pipes. A complete design procedure is adopted to conduct the design. Two new indices are constructed for evaluating the required properties of this robot.