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The purpose of this paper is to propose an optimization method by combining artificial immune algorithm and finite element analysis to find the optimal exciting electrode of a piezoceramic plate type ultrasonic motor vibrator.

The artificial immune algorithm is selected as optimizer for its merit of fast convergence to global optimal solution. The finite element analysis is used to calculate the motion trajectory of contact point. The objective function is the work that the vibrator does to rotor. The design variables are the boundaries of exciting electrode on piezoceramic plate vibrator surface.

The calculated results and the experimental results show that using this method, both the position and the size of optimal exciting electrode of this ultrasonic motor can be quickly and accurately determined.

In order to successfully design an ultrasonic motor, both the position and the size of the exciting electrode must be investigated, so as to change more electric energy into mechanical energy. In this paper, an optimization method by combining artificial immune algorithm and finite element analysis is proposed for the exciting location optimization of a piezoceramic plate type ultrasonic motor to obtain large power output.

The purpose of this study is to develop a piezoresistive absolute micro-pressure sensor for altimetry. For this application, both high sensitivity and high overload resistance are required. To develop a piezoresistive absolute micro-pressure sensor for altimetry, both high sensitivity and high-overload resistance are required. The structure design and optimization are critical for achieving the purpose. Besides, the study of dynamic performances is important for providing a solution to improve the accuracy under vibration environments.

An improved structure is studied through incorporating sensitive beams into the twin-island-diaphragm structure. Equations about surface stress and deflection of the sensor are established by multivariate fittings based on the ANSYS simulation results. Structure dimensions are determined by MATLAB optimization. The silicon bulk micromachining technology is utilized to fabricate the sensor prototype. The performances under both static and dynamic conditions are tested.

Compared with flat diaphragm and twin-island-diaphragm structures, the sensor features a relatively high sensitivity with the capacity of suffering atmosphere due to the introduction of sensitive beams and the optimization method used.

An improved sensor prototype is raised and optimized for achieving the high sensitivity and the capacity of suffering atmosphere simultaneously. A general optimization method is proposed based on the multivariate fitting results. To simplify the calculation, a method to linearize the nonlinear fitting and optimization problems is presented. Moreover, a differential readout scheme attempting to decrease the dynamic interference is designed.

The purpose of this paper is to explore how consumers’ trust is enhanced by e-commerce-based agribusiness companies. It also aims to shed light on the role of social commerce in improving consumers’ trust.

To achieve the research purpose, an in-depth multiple case study is performed. In this study, three cases in short food supply chain (SFSC) in China are selected, and they are all e-commerce agribusiness companies. They adopted common ways to build up, maintain and reinforce consumers’ trust.

It is revealed that the companies innovatively adopted social commerce, both online and offline, to overcome the trust problems usually faced by e-commerce companies. It is also shown that offline contact with potential consumers is an important first step for agribusiness e-commerce entrepreneurs to build up trust with consumers.

By adopting a multiple case study method, the research has limited generalizability to other types of SFSCs. Since the findings are from Chinese agribusiness e-commerce companies, the generalization to other sectors must be done with caution.

Some managerial implications are given as follows: first, offline contact with consumers could be realized through different channels. Taking advantage of existing social network or trying to find consumers in urban communities might be effective ways. Second, trust building with consumers is not an easy task, managers need to emphasize trust building, trust maintaining, as well as trust reinforcing with consumers. In agri-food sector, managers might need to specifically address the importance of food safety and quality so as to not lose consumer trust in one night.

The study has mainly two contributions: first, it has managerial implications for agribusiness e-commerce entrepreneurs, addressing the important role of social presence in building up consumer trust. Second, it contributes to social presence and social relations literature by providing new empirical evidence from e-commerce in agri-food sector and in developing countries.

The present article presents a first‐look into the hired‐labor market in Chinese household farms using data from a national household survey conducted by the Research Center for the Rural Economy (RCRE) at China's Ministry of Agriculture. More specifically, the purpose of this paper is to evaluate the scale and dispersion of China's farm‐household hired laborers among 15 commodities, and test whether market factors influence labor‐hiring decisions – an expectation of a well‐functioning labor market. This research contributes to the literature concerned with the labor constraints facing Chinese household farms, especially those producing seasonal commodities.

An econometric approach is employed to assess whether Chinese farms that hire labor are responding to market factors using two repeated cross‐sections (2006, 2007) of household survey data collected by the Research Center for Rural Economy at China's Ministry of Agriculture.

The paper finds hired labor use on very small‐scale farms is surprisingly prevalent, in contrast to previously published data. The regression results suggest that labor hiring by Chinese farm households, irrespective of farm size, responds strongly to market signals and resource constraints – more labor will be hired when the wage is lower, when output is higher, and among families with fewer family members available to farm work. And the response is particularly robust for wheat, rice, and maize, whose prices are predominant determinants of the food price index.

This paper is limited in its time‐series dimension and data availability. Despite those limitations, the results hold implications for further understanding China's nascent labor market and the level to which market factors have impacted rural farm households.

Focusing on the as‐of‐yet unstudied market for hired labor on Chinese household farms, the present article makes a contribution by showing that hiring of labor in Chinese agriculture is much more prevalent than previously thought. It suggests that Chinese farm‐households are responding to certain labor‐market factors and that the household response does not weaken as the largest farms are omitted from the model, suggesting that even small farms are heeding market signals.

In situations where the crew is reduced, the optimization of crew task allocation and sequencing (CTAS) can significantly enhance the operational efficiency of the man-machine system by rationally distributing workload and minimizing task completion time. Existing related studies exhibit a limited consideration of workload distribution and involve the violation of precedence constraints in the solution process. This study proposes a CTAS method to address these issues.

The method defines visual, auditory, cognitive and psychomotor (VACP) load balancing objectives and integrates them with workload balancing and minimum task completion time to ensure equitable workload distribution and task execution efficiency, and then a multi-objective optimization model for CTAS is constructed. Subsequently, it designs a population initialization strategy and a repair mechanism to maintain sequence feasibility, and utilizes them to improve the non-dominated sorting genetic algorithm III (NSGA-III) for solving the CTAS model.

The CTAS method is validated through a numerical example involving a mission with a specific type of armored vehicle. The results demonstrate that the method achieves equitable workload distribution by integrating VACP load balancing and workload balancing. Moreover, the improved NSGA-III maintains sequence feasibility and thus reduces computation time.

The study can achieve equitable workload distribution and enhance the search efficiency of the optimal CTAS scheme. It provides a novel perspective for task planners in objective determination and solution methodologies for CTAS.

In order to study the importance of climate comfortable conditions of urban public open spaces in marginal season of winter cities for people's outdoor activities, first, the paper ascertained the specific times of Harbin's outdoor and marginal seasons based on meteorological data from 1984 to 2013. Second, this paper conducted field survey, which includes in situ measurement and structured interview, in three typical urban public open spaces in marginal season. The calculated results show that Harbin has an outdoor season from Apr 25th to Oct 1st, and the spring marginal season is from Apr 4th to Apr 24th, the fall marginal season is from Oct 2nd to Oct 24th. At the same time, the results of in situ measurement show that there is great room for the improvement of climatic conditions of urban public open spaces in the marginal season of winter cities, especially the public open spaces near to the high-rise buildings and waterfront, and the apparent temperature in these two open spaces is about 3°C lower than the air temperature simultaneously. The results of structured interview show that people would like to do some outdoor activities when it is nice weather outside in marginal season, and the regression analysis results show that people's outdoor activities time are severely affected by climate comfortable conditions in marginal season. They feel that fine microclimate is much more important for a person than enough facilities and green landscape of urban public open spaces in marginal season. The paper suggested that the specific times of outdoor and marginal seasons should be added to some urban design guidance as a specification in urban planning practice, and this paper advanced some urban planning strategies related to urban design to improve climatic conditions of urban public open spaces in the marginal seasons of winter cities.

Man has been seeking an ideal existence for a very long time. In this existence, justice, love, and peace are no longer words, but actual experiences. How ever, with the American preemptive invasion and occupation of Afghanistan and Iraq and the subsequent prisoner abuse, such an existence seems to be farther and farther away from reality. The purpose of this work is to stop this dangerous trend by promoting justice, love, and peace through a change of the paradigm that is inconsistent with justice, love, and peace. The strong paradigm that created the strong nation like the U.S. and the strong man like George W. Bush have been the culprit, rather than the contributor, of the above three universal ideals. Thus, rather than justice, love, and peace, the strong paradigm resulted in in justice, hatred, and violence. In order to remove these three and related evils, what the world needs in the beginning of the third millenium is the weak paradigm. Through the acceptance of the latter paradigm, the golden mean or middle paradigm can be formulated, which is a synergy of the weak and the strong paradigm. In order to understand properly the meaning of these paradigms, however, some digression appears necessary.

Considers the factors which influence Taiwanese decisions to buy Japanese or US refrigerators, basing the conclusions on the results of a survey of 586 respondents drawn from Taiwan’s four largest cities – Taipei, Kaoshiung, Taichung and Tainan. Describes how the questionnaires were constructed and pretested, and explains how the data was recorded (using a 5‐point Likert‐type scale) and analysed (using factor analysis and t‐tests). Tests particularly for cultural values of the Chinese, consumer ethnocentrism, openness to foreign culture, country image, and consumer sophistication. Finds that, despite the longer presence of Japanese goods in Taiwan, Japan’s proximity to Taiwan, and more cultural similarities between the Japanese and Taiwanese, Taiwanese consumers rate the USA’s country image factor higher than Japan’s, with consequent implications regarding intention to buy US goods. Recommends that US marketers build on their advantageous country image when they promote US appliances in foreign markets. Cautions against making too much of this snapshot data but concedes that further research into different foreign markets, different appliances, and with a longitudinal approach, would ascertain if findings are consistent with this survey, which has obvious benefits as new markets, such as China and India, open up to western goods and appliances.

The purpose of this paper is to develop and empirically validate items on social isolation. The comprehensive literature review of existing studies on the measures of social isolation, loneliness and the related construct was conducted. The paper seeks to conceptualize, validate and present items to measure social isolation.

The paper is based on theoretical and empirical investigation of the measures of social isolation, loneliness and related constructs such as social others, social loneliness and feeling of sociability. The items were generated through theoretical exploration of previous literature and later modified. The author examined the items through exploratory factor analysis, confirmatory factor analysis and further checked for external criterion validity. Data collected from 128 individuals, in India, were examined to design and validate the scale.

The finding of the paper is a ten-item social isolation scale. Using structural equation modeling, we have found extraversion and well-being significantly associated with final items in the present study, confirming the external quality of the scale.

Organizations may benefit by close examination of the presence of social isolation in employees along with providing support and assistance to employees so as to reduce negative consequences of social isolation and can address the well-being of the employee.

There is a dearth of developed and validated measures of social isolation in the literature. The study reveals the conceptualization and empirical validation of measures of social isolation in the Indian context so that researchers can move forward to develop theories on social isolation.

The purpose of this paper is to make a comprehensive analysis of 354 publications about Pythagorean fuzzy sets (PFSs) from 2013 to 2020 in order to comprehensively understand their historical progress and current situation, as well as future development trend.

First, this paper describes the fundamental information of these publications on PFSs, including their data information, annual trend and prediction and basic features. Second, the most productive and influential authors, countries/regions, institutions and the most cited documents are presented in the form of evaluation indicators. Third, with the help of VOSviewer software, the visualization analysis is conducted to show the development status of PFSs publications at the level of authors, countries/regions, institutions and keywords. Finally, the burst detection of keywords, timezone review and timeline review are exported from CiteSpace software to analyze the hotspots and development trend on PFSs.

The annual PFSs publications present a quickly increasing trend. The most productive author is Wei Guiwu (China). Wei Guiwu and Wei Cun have the strongest cooperative relationship.

The implication of this study is to provide a comprehensive perspective for the scholars who take a fancy to PFSs, and it is valuable for scholars to grasp the hotspots in this field in time.

It is the first paper that uses the bibliometric analysis to comprehensively analyze the publications on PFSs. It can help the scholars in the field of PFSs to quickly understand the development status and trend of PFSs.