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The purpose of this paper is to present the static and dynamic characteristics of the rehabilitation joint.

The rehabilitation joint is driven by pneumatic muscle actuators (PMAs). Rehabilitation robot is normally composed of several rehabilitation joints. The static and dynamic characteristics of the rehabilitation joint are important for control of the rehabilitation robot. Analysis and modeling of the rehabilitation joint is based on experiments.

The static model of the PMA is obtained by the method of curve fitting and achieved better precision compared to the existing representative models. A second‐order model fits the dynamic characteristic of the rehabilitation joint better than a first order one.

The rehabilitation joint and the patient's joint combine to make an independent system, and the unstable factors of the patient's joint make it difficult in precisely modeling the rehabilitation joint.

The characteristics of the rehabilitation joint are all based on the data that were recorded in a series of with experiments, the same with modeling of the rehabilitation joint.

This study aims to explore the dual identity role of joint gift-giving among adolescents. Studying this phenomenon through the lens of impression management theory enabled us to analyze private and group motives, drivers of these motives (givers’ public self-consciousness and self-monitoring and group cohesiveness) and the influence of group motives on the joint process. The characteristics of the joint process reflect a mutual social activity that enables adolescents to strengthen social group ties and define and nurture group identity. This research showed how a mutual consumer process, specifically, joint gift-giving, enhances the outcomes of social resources by defining groups’ mutual extended selves.

In this study, quantitative tools were used. Selection of constructs for the study was based on a literature review and existing qualitative research. To test the validity and the reliability of the scales, a convenience sample of 103 adolescents (13 to 16 years old) was used in a pre-test survey. In the main study, a convenience sample of 129 adolescences was used. Self-report questionnaires were distributed to adolescents (aged 13-16 years). The survey included scales covering private and group motives for joint gift-giving, givers’ personality, group cohesiveness and the characteristics of the joint process.

Givers’ public self-consciousness and self-monitoring were positively related to the motivation to engage in joint gift-giving to facilitate the development of desired private identities. High public self-consciousness and self-monitoring givers were motivated to enhance their private role in the group task and managed their impression among multiple audiences. We found that high-cohesiveness groups were motivated to nurture and strengthen social resources through joint gift-giving. Engaging in joint gift-giving is motivated not only by functional motives (e.g. saving money) but also by social motives that strengthen a group’s extended-self and social resources that all members enjoy.

Although gift-giving is a three-stage process per gestation presentation and reformulation stage, the current study explored joint gift-giving behavior only in the gestation stage. Future research should include the other two stages. Also the current research concentrated on adolescents. Exploring joint gift-giving among adults is recommended as well. Comparing the two age groups should allow a better understanding of the special characteristics of adolescents and adults. Additionally, other personality characteristics could affect givers private identity in the group task and other group characteristics such as group size gender of members and group context in the workplace could affect identity.

This research can provide marketers with a deeper understanding of the joint gift-giving process. For example, marketers should recognize that joint gift-giving involves adolescent groups’ time-consuming activities in the joint process, i.e. gift selection effort, making handmade gifts and putting special efforts in gift appearance that enable them to define and nurture their group identity.

Parents and educators should recognize the importance of social identity dual role in participating in joint gift-giving. Hence, we recommend them to encourage adolescents to participate in this joint consuming process to enable them to protect and define their identity.

Adolescents are an important market segment with unique cognitive, social and personality processes. While these processes have been explored in several consumer behavior studies, adolescents’ gift-giving has been largely ignored in the literature. This study contributes to an understanding of the drivers of private and group joint gift-giving motives, how sense of belonging and group identity are reflected in the social dynamics of joint gift-giving and how adolescents manage group and private impressions in the eyes of a single receiver and in the eyes of multiple peers participating in the group task.

Examines the determinants of International Joint Venture marketing performance in Thailand. Uses the results from a survey of 1047 Thai‐foreign IJVs in Thailand from firms that were mainly engaged in agriculture, metal working, electrical and chemical industries. Applies exploratory factor analysis and discriminant analysis to identify these critical determinants as market characteristics, conflict, commitment, marketing orientation and organisational control.

The purpose of the present study was to review the thermo-mechanical challenges of reflowed lead-free solder joints in surface mount components (SMCs). The topics of the review include challenges in modelling of the reflow soldering process, optimization and the future challenges in the reflow soldering process. Besides, the numerical approach of lead-free solder reliability is also discussed.

Lead-free reflow soldering is one of the most significant processes in the development of surface mount technology, especially toward the miniaturization of the advanced SMCs package. The challenges lead to more complex thermal responses when the PCB assembly passes through the reflow oven. The virtual modelling tools facilitate the modelling and simulation of the lead-free reflow process, which provide more data and clear visualization on the particular process.

With the growing trend of computer power and software capability, the multidisciplinary simulation, such as the temperature and thermal stress of lead-free SMCs, under the influenced of a specific process atmosphere can be provided. A simulation modelling technique for the thermal response and flow field prediction of a reflow process is cost-effective and has greatly helped the engineer to eliminate guesswork. Besides, simulated-based optimization methods of the reflow process have gained popularity because of them being economical and have reduced time-consumption, and these provide more information compared to the experimental hardware. The advantages and disadvantages of the simulation modelling in the reflow soldering process are also briefly discussed.

This literature review provides the engineers and researchers with a profound understanding of the thermo-mechanical challenges of reflowed lead-free solder joints in SMCs and the challenges of simulation modelling in the reflow process.

The unique challenges in solder joint reliability, and direction of future research in reflow process were identified to clarify the solutions to solve lead-free reliability issues in the electronics manufacturing industry.

To study fracture characteristics of jointed rock masses under blasting load, the RFPA2D analysis software for dynamic fracture of rocks based on the finite element method and statistical damage theory was used.

On this basis, this research simulated the fracture process of rock masses in blasting with different joint geometrical characteristics and mainly analysed the influences of distance from joints to blasting holes, the length of joints, the number of joints and joint angle on fracture of rock masses.

The calculation results show that with the constant increase of the distance from joints to blasting holes, the influences of joints on blasting effects of rock masses gradually reduced. Rock masses with long joints experienced more serious damages than those with short joints. Damages obviously increased with the changing from rock masses without joints to rock masses with joints, and when there were three joints, the further increase of the number of joints had unobvious changes on blasting effects of rock masses. Joints showed significant guidance effect on the propagation of cracks in blasting: promoting propagation of main vertical cracks deflecting to the ends of joints.

The research results are expected to provide some theoretical bases in practical application of engineering blasting.

The purpose of this paper is to discuss the capability of finite element analysis (FEA) in performing the virtual thermal cycling reliability test to evaluate the reliability of solder joints in a ball grid array (BGA) package.

Thermal cycling test has been used to evaluate the reliability or fatigue life of the solder joints in BGA package using commercially available FEA software, ANSYS™. The effect of different temperature cycling condition is studied by applying different value of dwell time and ramp rate. Two types of analyses are used namely, the physics‐based analysis and the statistical‐based analysis. Two screening design methods namely, central composite design (CCD) and Box‐Behnken Matrix Design method are used to isolate the most important factors amongst six selected design variables. The optimization process is carried out using response surface methodology (RSM).

It is observed that changes in ramp rate produce significant effect in solder fatigue life than changes in dwell time but the dwell time at high temperature has a negligible contribution to solder fatigue life. It has been found that the thickness of the mold has a significant effect on the performance of the solder joint reliability (more than 50 percent) as compared to that from other factors. Besides, the effect of individual factor, the interaction among factors also changes the solder joint reliability. RSM based on Box‐Behnken Matrix design offers the highest characteristic solder joint fatigue life with a value of 2,861 cycles.

This paper provides a comprehensive method to evaluate the reliability of solder joints in terms of physics and statistical‐based analysis.

Aims to present a finite element analysis based methodology for estimating the characteristic fatigue life of a solder joint interconnect under accelerated temperature cycling to predict the reliability performance of a flip chip package.

The method uses the ANSYSTM finite element analysis tool along with Anand's viscoplastic constitutive law. Darveaux's crack growth rate model was applied to calculate solder joint characteristic life using simulated viscoplastic strain energy density results at the package substrate and printed circuit board solder joints. Two package configurations are evaluated with the above methodology, with the first being a simplified flip chip model and the second being a detailed flip chip model. Each of these configurations is subjected to two accelerated temperature cycling tests.

Generally, the results indicate that the solder joint at the corner end of the package tends to fail first. The characteristic lives of solder joint at the package ball/board interface are 24‐46 percent higher than the characteristic lives of solder joint at the package ball/substrate interface. This means that the interface between the solder ball and substrate will fail first before the interface between the solder ball and the board.

Demonstrates that genetic algorithms can be used as tools to predict possible package dimensional values for given constraints on solder joint life.

Effective leadership is a key factor in successful international joint ventures, especially in Vietnam. Compatibility and complementarity of the leadership styles are the foundation for such partnerships. Based on a research study of international managers and their Vietnamese counterparts, an appropriate profile of compatible and complementary leadership characteristics and effective skills and behaviors for successful joint ventures in Vietnam is suggested. A multi‐cultural approach with focus on the mutual understanding of the cultures involved, adapting the styles of the partners and relationship building is necessary for successful joint ventures. Building shared values in the joint venture is critical to performance, to creating an appropriate organizational culture, and to accomplishing effective organizational change.

The purpose of this paper is to evaluate three categories of four-degrees of freedom (4-DOFs) upper limb rehabilitation exoskeleton mechanisms from the perspective of relative movement offsets between the upper limb and the exoskeleton, so as to provide reference for the selection of exoskeleton mechanism configurations.

According to the configuration synthesis and optimum principles of 4-DOFs upper limb exoskeleton mechanisms, three categories of exoskeletons compatible with upper limb were proposed. From the perspective of human exoskeleton closed chain, through reasonable decomposition and kinematic characteristics analysis of passive connective joints, the kinematic equations of three categories exoskeletons were established and inverse position solution method were addressed. Subsequently, three indexes, which can represent the relative movement offsets of human–exoskeleton were defined.

Based on the presented position solution and evaluation indexes, the joint displacements and relative movement offsets of the three exoskeletons during eating movement were compared, on which the kinematic characteristics were investigated. The results indicated that the second category of exoskeleton was more suitable for upper limb rehabilitation than the other two categories.

This paper has a certain reference value for the selection of the 4-DOFs upper extremity rehabilitation exoskeleton mechanism configurations. The selected exoskeleton can ensure the safety and comfort of stroke patients with upper limb dyskinesia during rehabilitation training.

This paper aims to monitor, evaluate and adjust the joint quality of dissimilar friction stir welded AA2024-T3 and AA7075-T6 Al alloys.

Taguchi analysis for design of experiments and ANOVA analysis were applied. Tensile test, visual inspection and macro and microstructure investigations were carried out at each welding condition. In addition, the grain size of stir zone and the value of heat input were measured.

Using Taguchi analysis, the optimum values of tool rotary speed, welding speed and axial load were 1,200 rpm, 100 mm/min and 1,300 kg, respectively, yielding the maximum tensile strength of the joints of 427 MPa. ANOVA analysis indicated that the most significant parameter on the joint strength is the tool rotary speed, followed by welding speed and axial load, with contributions of 67, 27 and 2 per cent, respectively. Best mixing between Al alloys in the stir zone with no defects was observed at moderate speeds because of proper heat input and grain size, resulting in high strength.

A relation between structure characteristics of the joint, the process parameters and the joint strength was established to control the joint quality.