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The existing Nonlinear Dynamic Vibration Absorbers (NLDVAs) have the disadvantages of complex structure, high cost, high installation space requirements and difficulty in miniaturization. And most of the NLDVAs have not been applied to reality. To address the above issues, a novel Triple-magnet Magnetic Dynamic Vibration Absorber (TMDVA) with tunable stiffness, only composed of triple cylindrical permanent magnets and an acrylic tube, is designed, modeled and tested in this paper.

(1) A novel TMDVA is designed. (2) Theoretical and experimental methods. (3) Equivalent dynamics model.

It is found that adjusting the magnet distance can effectively optimize the vibration reduction effect of the TMDVA under different resonance conditions. When the resonance frequency of the cantilever changes, the magnet distance of the TMDVA with a high vibration reduction effect shows an approximately linear relationship with the resonance frequency of the cantilever which is convenient for the design optimization of the TMDVA.

Both the simulation and experimental results prove that the TMDVA can effectively reduce the vibration of the cantilever even if the resonance frequency of the cantilever changes, which shows the strong robustness of the TMDVA. Given all that, the TMDVA has potential application value in the passive vibration reduction of engineering structures.

Developing waterway-waterway transfer is an important path for Shanghai's container logistics to innovate service models. Taicang Express Line, a typical case of service model innovation, plays an important role in elevating the standing of Shanghai Port as a container hub port and in developing China (Shanghai) Pilot Free Trade Zone. From the three dominant transfer service models, the waterway-waterway transfer for container logistics of Taicang Express Line has the traits and experience in streamlining logistics processes, innovating logistics clearance models, saving logistics operating costs, offering port logistics cooperation experience for replications and promoting integration of regional port logistics resources. However, it also harbors issues in infrastructure construction, staffing, container resources allocation and transportation, transportation efficiency and policy innovation. In the future, efforts should be invested to strengthening the construction and staffing of port logistics infrastructure, optimizing the container resources allocation and transport of port logistics systems, improving the logistics transportation efficiency of Taicang Express Line, and pushing forward innovation of the synergistic policy mechanism for regional port logistics.

Developing waterway-waterway transfer is an important path for Shanghai's container logistics to innovate service models. Taicang Express Line, a typical case of service model innovation, plays an important role in elevating the standing of Shanghai Port as a container hub port and in developing China (Shanghai) Pilot Free Trade Zone. From the three dominant transfer service models, the waterway-waterway transfer for container logistics of Taicang Express Line has the traits and experience in streamlining logistics processes, innovating logistics clearance models, saving logistics operating costs, offering port logistics cooperation experience for replications and promoting integration of regional port logistics resources. However, it also harbors issues in infrastructure construction, staffing, container resources allocation and transportation, transportation efficiency and policy innovation. In the future, efforts should be invested to strengthening the construction and staffing of port logistics infrastructure, optimizing the container resources allocation and transport of port logistics systems, improving the logistics transportation efficiency of Taicang Express Line, and pushing forward innovation of the synergistic policy mechanism for regional port logistics.

Inequality is an essential factor for the alleviation of poverty. In Cameroon, most of the households derive their livelihoods from non-wage income and a better understanding of how different variables affect income inequality is a way to reduce those inequalities and improve social welfare. Studies carried out so far barely make out the determinants among non-wage earners. This study sets out to identify these determinants, using the regression-based decomposition technique and data obtained from the 2005 Employment and Informal Sector Survey (EISS) undertaken by the National Statistic Institute (INS) in Cameroon. Results show that the total inequality of an hourly active income ensues from the ratio of age/experience and unobserved individual heterogeneity among non-wage earners.

This paper devises a new method for using the information contained in income-generating equations to “account for” or “decompose” the level of income inequality in a country and its change over time. In the levels decomposition, the shares attributed to each explanatory factor are independent of the particular inequality measure used. In the change decomposition, methods are presented to break down the contribution of each explanatory factor into a coefficients effect, a correlation effect, and a standard deviation effect. In an application to rising earnings inequality in the United States, it is found that schooling is the single most explanatory variable, only one other variable (occupation) has any appreciable role to play, and all of schooling’s effect was a coefficients effect.

This paper aims to design a novel jaw gripper with human-sized anthropomorphic features to be suitable for precise in-hand posture transitions, such as twisting and re-positioning. The growing demand from traditional high-mix low-volume and new massive customized manufacturing industry requires the robot with configurability and flexibility. In the electronic manufacturing industry particularly, the design of the robotic hand with sufficient dexterity and configuration is important for the robot to accomplish the assembly task reliably and robustly. It is important for the robot to be able to grasp and manipulate a large number of assembly parts or tools.

In this research, a novel jaw-like gripper with human-sized anthropomorphic features is designed for online in-hand precise positioning and twisting. It retains the simplicity feature of traditional industrial grippers and dexterity features of dexterous robotic hands.

The gripper is able to apply suitable gripping force on assembly parts and performs reliable twisting movement within limited time to meet the industrial requirements. Manipulating several cylindrical assembly parts by robot, as an experimental case in this paper, is studied to evaluate its performance. The effectiveness of proposed gripper design and mechanical analysis is proved by the simulation and experimental results.

The main originality of this research is that a novel jaw gripper with human-sized anthropomorphic features is designed to be suitable for precise in-hand posture transitions, such as twisting and re-positioning. With this gripper, the robotic system will be sufficiently flexible to deal with various assembly tasks.

The purpose of this paper is to use the Black-Scholes-Merton option pricing model to evaluate the incremental performance of an eChannel addition.

Data were collected from 53 Taiwan financial services firms. In total, 33 of them introduced their online services, whereas the other 20 firms did not introduce their online services during the period under examination.

The research findings show that firm asset values increase following eChannel additions. Thus, eChannel additions enhance firm financial performance. A further analysis comparing the performance between firms with and without eChannel additions also shows that firms with eChannel additions have higher asset value growth rates, which further validates the capacity of eChannel additions to enhance financial performance.

Managers and shareholders in firms making eChannel additions are not required to be concerned regarding stock price volatility, and managers in firms without any eChannel investment could use eChannels to enhance their stock price and seize future opportunities. Using eChannel is a valid approach for firms to provide enhanced services to current customers, access new markets, and extend market coverage, thus enhancing overall financial performance. Investors could confide those firms implementing eChannel additions.

Studies investigating whether eChannel additions enhance firm financial performance are scant. No study has evaluated performance from a long-term perspective or from a volatility aspect (both are important considerations in eChannel performance evaluation). The research represents a pioneering work that empirically investigates these issues.

Given the rapid growth of the Chinese cruise market, several Chinese cities are attempting to become a hub for cruise ships. The aim of this study is to evaluate the competitiveness of those cities with regard to hosting cruises. It employs a cloud model that transforms the qualitative description of competitive indicators into quantitative measurement and assesses the competitive advantage and specialization of the top homeports in China. Questionnaires are delivered to experts from eight cruise ports in China and the cloud model based on 14 evaluation factors is used to analyze the competitiveness of the ports under investigation. The result shows that the city’s scale, population, and development have been the main factors for assessing the competitiveness of port cities. The research provides insight about the Chinese cruise port cities’ competitiveness, which is particularly useful for future development decision and marketing strategies of ports and prospective destinations.

Peer‐to‐peer (P2P) communities have the capability to construct a powerful virtual supercomputer by assembling idle internet cycles. The purpose of this paper is to present the scheduling issues in an unstructured P2P‐based high performance computing (HPC) system to achieve high performance for applications.

A new application model is proposed for the system, where applications are parallelized in the program level. To address high performance for these applications, the system resources are controlled in a semi‐centralized 3‐layer network, where volunteers form many autonomous unstructured P2P domains. Furthermore, based on such a resource management policy, a job scheduling strategy is adopted, which is collaborated by global and domain scheduling. The global scheduling is responsible for the balance among domains, while the domain scheduling resolve workpiles' execution in a domain.

Theoretical analysis and a benchmark experiment show that the scheduling provides scalable and enormous computing capability in the P2P‐based HPC system.

The paper shows that scheduling helps P2HP (an unstructured P2P‐based HPC system) provide scalable and enormous computing capability for HPC applications.

The objective of this paper is to examine the affect of foreign remittances on the distribution of incomes in the home country. As noted recently by Stark, Taylor and Yitzhaki (1986), there are few works which deal with the distributional impact of revenues from abroad. This is probably due to the lack of adequate data, since the available data in most instances refer only to the overall magnitude of transfers (i.e. are considered almost exclusively from a balance of payments perspective). More empirical information on the distributional effects of workers' remittances is needed for the following reason. Existence of remittances can no longer be considered a transitory phenomenon. The importance of inter‐country migrations remains high and remittances continue to provide a substantial portion of foreign exchange resources for a number of countries. Their distributional effects cannot be ignored. Thus even if migration and the inflow of remittances associated with it do raise welfare in the source country when income distribution is implicitly assumed unchanged (see Djajic, 1986) the effects can be ambiguous once this assumption is relaxed. If remittances tend to lower overall income inequality their effect can be both positive in welfare terms and politically stabilising. The reverse, however, holds if they lead to an increase in income inequality.