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The original v2-based sectional method assumes that the selected property quantity of particles is uniformly distributed in each section, which makes particle size distribution (PSD) fluctuate dramatically in the entire size range. The number concentration in each section as well as the zeroth moment of PSD also cannot be correctly predicted in case there are not enough sections used in calculation. In order to provide a more appropriate representation of PSD, different approximate models are used to close the conservation equations. The paper aims to discuss these issues.

The uniform distribution of the selected property quantity of particles in each section is not necessarily satisfied. Instead, the distribution is approximated using an expression with an approximation factor. Different models are investigated on recovering the initial size distribution and predicting the time evolution of size distribution as well as the first three moments so that the advantages and disadvantages of each model can be compared.

The approximate model with an approximation factor of 0.8 is capable of predicting the time evolution of the zeroth moment accurately no matter how many sections are used in simulations. The original v2-based model is recommended to calculate the first and second moments as long as the section number is larger than 50, otherwise, the model with an approximation factor of 0.15 would be a preferred choice.

Different approximate models can be used to improve the accuracy of the results supposing we know which moment is of great importance in calculation.

The purpose of this paper is to develop new types of direct expansion method of moments (DEMM) by using the n/3th moments for simulating nanoparticle Brownian coagulation in the free molecule regime. The feasibilities of new proposed DEMMs with n/3th moments are investigated to describe the evolution of aerosol size distribution, and some of the models will be applied to further simulation of physical processes.

The accuracy and efficiency of some kinds of methods of moments are mainly compared including the quadrature method of moments (QMOM), Taylor-expansion method of moments (TEMOM), the log-normal preserving method of moments proposed by Lee (LMM) and the derived DEMM in this paper. QMOM with 12 quadrature approximation points is taken as a reference to evaluate other methods.

The newly derived models, namely DEMM(4/3,4) and DEMM(2,6), as well as the previous DEMM(2,4), are considered to be qualified models due to their high accuracy and efficiency. They are confirmed to be valid and alternative models to describe the evolution of aerosol size distribution for particle dynamical process involving the n/3th moments.

The n/3th moments, which have clear physical interpretations when n stands for first several integers, are first introduced in the DEMM method for simulating nanoparticle Brownian coagulation in the free molecule regime.

The purpose of this study is to obtain an effective implant with porous structures on its surface, named porous-surfaced implant, which helps to improve the overall stability of the implant and promote the combination of implant and alveolar bone.

Porous-surfaced implants with a porosity of 16%, 21%and 32% were designed and the effect of porosity on the strength of the implant was analyzed by ABAQUS software. Porous-surfaced implants with different porosity were printed by selective laser melting and the surface morphology was observed. Animal experiments of implants with porous structures and coating were carried out in healthy beagle dogs. The experimental group was treated with hydroxyapatite coating and the control group was not treated. Bone volume (BV) and total volume (TV) of the implant surface of the experimental group and control group were calculated by Skyscan CTvol software.

With the increase of porosity of porous-surfaced implants, the neck stress of the porous-surfaced implants increased and their strength decreased. In addition, in animal vivo experiments, the ratio value of BV to TV of the porous-surfaced implants was between 55.38% and 79.86%, which was the largest when the porosity of porous-surfaced implants was 16%. The internal and surrounding bone formation content of porous-surfaced implants with hydroxyapatite coating was higher than porous-surfaced implants without coating.

The results of this study show that the pores on the surface of implants can be filled with the new bone and porous-surfaced implants with 16% porosity provide better space for the growth of new bone. The porous structures with hydroxyapatite coating are beneficial to the growth of new bone around implants. The results of this study are helpful to improve the overall stability of implants and to promote the combination of implant and alveolar bone.

This study aims to explore the impact of social capital on job performance when workers interact with coworkers through social media in organizations.

Structural equation modeling was conducted, and a sample of 230 workers in Taiwan was investigated.

This study found that bonding social capital has a greater impact on job performance than bridging social capital for interactions among coworkers through social media in organizations. Moreover, bridging social capital affects job performance more strongly for male workers than for female workers, but bonding social capital affects job performance more strongly for female workers than for male workers.

This study extended social capital theory by adding the mediating effects of job satisfaction and relational satisfaction and the moderating effect of gender into the model.

This study suggests that company managers need to train workers how to use social media to appropriate their affordances and consider the work team relationship to position adequate strategies for male and female workers.

This study advances the previous knowledge of social capital theory for workers interacting with coworkers through social media in organizations.

This paper aims to establish the predictive equations of height, area and volume of printed solder paste during solder paste stencil printing (SPSP) process in surface mount technology (SMT) to better understand the effect of process parameters on the printing quality.

An experiment plan is proposed based on the response surface method (RSM). Experiments with 30 different combinations of process parameters are performed using a solder paste printer. After printing, the volume, area and height of the printed SAC105 solder paste are measured by a solder paste inspection machine. Using RSM, the predictive equations associated with the printing parameters and the printing quality of the solder paste are formed.

The optimal printing parameters are 175.08 N printing pressure, 250 mm/s printing speed, 0.1 mm snap-off height and 15.7 mm/s stencil snap-off speed if the target height of solder paste is 100 µm. As the target printing area of solder paste is 1.1 mm × 1.3 mm, the optimized values of the printing parameters are 140.29 N, 100.52 mm/s, 0.63 mm and 20.25 mm/s. When both the target printing height and area are optimized together, the optimal values for the four parameters are 86.67 N, 225.76 mm/s, 0.15 mm and 1.82 mm/s.

A simple RSM-based experimental method is proposed to formulate the predictive polynomial equations for height, area and volume of printed solder paste in terms of important SPSP parameters. The predictive equation model can be applied to the actual SPSP process, allowing engineers to quickly predict the best printing parameters during parameter setting to improve production efficiency and quality.

Software process improvement (SPI) is a knowledge activity that is critical to the excellence of information system development. This study observes two knowledge gaps in the quest for SPI success and proposes a research model that integrates existing knowledge antecedents to address these gaps. Based on organizational learning theory and the dynamic capability view, the proposed model consolidates a firm's absorptive capacity (AC), learning ability in terms of exploration and exploitation and knowledge sharing (KS), and it examines the contextual relationships among these knowledge antecedents on the path to SPI success.

A quantitative research design is implemented to examine the model with a sample of 138 SPI-certified organizations in Taiwan and Mainland China. The partial least squares (PLS) technique is used for the data analysis.

The results reveal the following findings. First, AC triggers the effect of exploration/exploitation on SPI success. Second, KS fosters exploitation but has an insignificant influence on exploration. Third, KS can promote AC, and it serves as the sourcing mechanism for all of the knowledge antecedents. Overall, an integrative set of knowledge learning routes is presented in guiding software firms on the way to SPI success.

In addition to identification of the two knowledge gaps, this study advances the authors’ understanding by comprehending the causal associations of the four knowledge antecedents on the way to SPI success.

To deepen our understanding about the development of team performance, the purpose of this paper is to develop a model that explains how ambidexterity and ethical leadership affect knowledge sharing and team performance through within-team competition.

This study demonstrates the applicability of ambidexterity and within-team competition by surveying 78 teams from the high-tech and banking industries. This study further presents a three-way interaction among ambidexterity, politics and job complexity.

This study finds that both ambidexterity and ethical leadership are positively related to knowledge sharing and team performance through the mediation of team development competition.

This study confirms that ambidexterity and ethical leadership play critical factors for improving knowledge sharing and team performance through the mediation of team development competition. Furthermore, the moderating effects of politics and job complexity are also confirmed in the research.

Knowledge sharing usually happens in a work group context, but it is rarely know how group leaders influence their members’ knowledge-sharing performance. Based on social exchange theory (SET) and the perspective of positive organizational behavior (POB), this study aims to argue that a group leader’s positive leadership (e.g. empowering leadership) can help group members develop positive psychological capital which can increase their knowledge sharing.

The authors conduct a multilevel analysis to explore the interrelationship among empowering leadership, psychological capital and knowledge sharing. The sample includes 64 work groups consisting of 537 group members, and empirical testing is carried out by hierarchical linear modeling.

The results show that empowering leadership in a work group has a direct cross-level impact on members’ knowledge sharing and that psychological capital partially mediates the relationship between empowering leadership and knowledge sharing. As a result, this study shows that group leaders with positive leadership can help their members develop better positive psychological resources, which should lead to better knowledge sharing.

Based on the multilevel perspective and SET, this is the first study to explore how group leaders’ empowering leadership influences members’knowledge sharing. Depending on integrating the POB perspective into SET, this study is also the first one that connects two emerging and important research issues – POB and knowledge sharing.

Although the work group is the main context for knowledge exchange and combination in today’s organizations, few knowledge-sharing studies have been conducted at the group level. The purpose of this paper is to apply the concept of group social capital to determine how to promote knowledge sharing at the group level. The authors divided group social capital into two segments, conduits and resources, and argue that different group social capital conduits (i.e. work design in this study) lead to varied resources, which subsequently influence group knowledge sharing.

In this study, group social capital conduits included social interaction and task interdependence, and group social capital resources included group trust and a supportive climate for knowledge sharing. The authors conducted a survey on work groups in the high-tech industry using a sample of 86 work groups.

The results indicated that social interaction in a work group was positively related to group trust and that task interdependence was positively related to group trust and a supportive climate for knowledge sharing. Furthermore, group trust and a supportive climate for knowledge sharing were both found to have an influence on knowledge sharing.

Applying the concept of group social capital, this paper is the first research to discuss how group social capital conduits and resources influence knowledge sharing. The results of this study lead us to a better understand the relationship between group social capital and knowledge sharing.

This study aims to introduce an empirical model which incorporates newsgroups, knowledge forums, knowledge assets and knowledge application processes to share organisational knowledge. Therefore it seeks to illustrate an application for integrating knowledge management (KM) into the business process.

The Taiwanese contingent of an international certification body – also a council member of the International Organisation for Standardisation (ISO) – was selected for a case study. A hybrid technology infrastructure was designed and employed to implement the proposed model. Based on knowledge value added validation, the proposed KM model provides a set of new operating systems for sharing knowledge within an organisation.

Although many theories regarding implementation of KM in organisations have been proposed and studied, an application model for practical integration of various modern principles to share organisational knowledge is strategically important. Therefore a model that integrates principal KM applications into the business process, and the measurement of the resulting benefits, has been developed.

Knowledge is a valuable asset for an individual in today's economy; nevertheless the acquisition of such an asset relies heavily on knowledge sharing within an organisation. The author has proposed an exclusive hybrid platform with an empirical process model to address innovative approaches and practical values of KM within an organisation.