• Journal of Institute of Control, Robotics and Systems
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• v.13 no.11
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• pp.1099-1105
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• 2007

In this paper, modified two-port time-domain passivity approach is proposed for stable bilateral control of teleoperators under time-varying communication delay. We separate input and output energy at each port of a bilateral controller, and propose a sufficient condition for satisfying the passivity of the bilateral controller including time-delay. Output energy at the master port should be less than the transmitted input energy from the slave port with time-delay, and output energy at the slave port should be less than the transmitted input energy from the master port with time-delay. For satisfying above two conditions, two passivity controllers are attached at each port of the bilateral controller. A packet reflector with wireless internet connection is used to introduce serious time-varying communication delay of teleoperators. Average amount of time-delay was about 190(msec) for round trip, and varying between 175(msec) and 275(msec). Moreover some data packet was lost during the communication due to UDP data communication. Even under the serious time-varying delay and packet loss communication condition, the proposed approach can achieve stable teleoperation in free motion and hard contact as well.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.4
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• pp.390-396
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• 2011

Southern rough shrimp Trachysalambria curvirostris is exploited mainly by small shrimp beam trawl in coastal regions of Korea. To determine the size selectivity of a shrimp beam trawl for this species, a series of comparative fishing experiments was conducted in the sea adjacent to Geoje Island off the southern cost of Korea in June and November, 2010, using codends with four different mesh sizes(14.2, 17.8, 25.5, and 35.3 mm). The extended Share Each Length's Catch Total(SELECT) analysis method, based on a multinomial distribution, was applied to the fishing data to obtain a master selection curve. The model with the estimated split parameters fit the catch data best. The master selection curve was estimated to be: s(R)=exp(15.183R-7.872)/[1+exp(15.183R-7.872)], where the relative carapace length, R, is the ratio of carapace length to mesh size. The relative carapace length for 50% retention was 0.518, and the selection range was 0.145. The results suggest that codends with a larger mesh size allow more small-sized shrimps to escape.

• Computers and Concrete
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• v.2 no.2
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• pp.97-110
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• 2005

Rheological behaviour of fresh concrete is an important factor in controlling concrete quality. It is recognized that the measurement of the slump is not a sufficient test method to adequately characterize the rheology of fresh concrete. To further understand the slump measurement and its relationship to the rheological properties, an elasto-viscoplastic, 2-D axisymmetric finite element (FE) model is developed. The FE model employs the Bingham material model to simulate the flow of a slump test. An experimental program is carried out using the Slump Rate Machine (SLRM_II) to evaluate the finite element simulation results. The simulated slump-versus-time curves are found to be in good agreement with the measured data. A sensitivity study is performed to evaluate the effects of yield stress, plastic viscosity and cone withdrawal rate on the measured flow curve using the FE model. The results demonstrate that the computed yield stress compares well with reported experimental data. The flow behaviour is shown to be influenced by the yield stress, plastic viscosity and the cone withdrawal rate. Further, it is found that the value of the apparent plastic viscosity is different from the true viscosity, with the difference depending on the cone withdrawal rate. It is also confirmed that the value of the final slump is most influenced by the yield stress.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.6
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• pp.123-132
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• 1999

This paper describes a research work of developing computer-aided design of lead frame, semiconductor, with blanking operation which is very precise for progressive working. Approach to the system is based on the knowledge-based rules. Knowledge for the system is formulated from pasticity theories, experimental results and the empirical knowledge of field experts. This system has been written in AutoLISP on the AutoCAD using a personal computer and in I-DEAS Drafting Programming Language on the I-DEAS Master Series Drafting with Workstation, HP9000/715(64). Transference of data between AutoCAD and I-DEAS Master Series Drafting is accomplished by DXF(drawing exchange format) and IGES(initial graphics exchange specification) methods. This system is composed of five modules, which are input and shape treatment, production feasibility check, strip-layout, data-conversion and die-layout modules. The process planning and Die design system is designed by considering several factors, such as complexities of blank geometry, punch profiles, and the availability of a press equipment and standard parts. This system provides its efficiecy for strip-layout, and die design for lead frame, semiconductor.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.947-953
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• 2020

The main purpose of this study is to find the factors affecting the consumer goods buyers' choice on e-commerce sites in Vietnam. By using the quantitative method, the paper examines the theoretical research model and tests four hypotheses. The sample was drawn from the population of e-commerce sites in Vietnam comprising about 1,000 respondents. This study used the questionnaire method to collect primary data to test the hypotheses. Data analysis of the questionnaire was done using SPSS. The results show that there is a correlation between personal preferences of consumers on colors and brands and their actual final choice on e-commerce sites in Vietnam. The most important factor affecting the consumer goods buyers' choice on e-commerce in Vietnam is the brand of E-commerce site, following by the color and position. Among all educational groups, respondents with a Master degree pay the biggest attention to the site's color attribute, and those with a Bachelor degree pay more attention to the brand attribute. Women pay much more attention to the location of the products on the screen than men, as do consumers with a PhD degree, over respondents with a Bachelor or Master degree, and foreigners over Vietnamese consumers.

• Journal of Korean Academy of Nursing Administration
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• v.19 no.3
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• pp.382-393
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• 2013

Purpose: The purpose of this study was to review journal articles, master's theses, and doctoral dissertations on self-leadership in nurses in order to identify overall trends in nursing self-leadership and to suggest strategies to improve self-leadership. Methods: Twenty-six papers on self-leadership in nurses were reviewed. Results: These papers were journal articles, master's theses, and doctoral dissertations regarding nurses who worked in general hospitals, university hospitals, and public health centers. Self-leadership was measured by using instruments developed by Manz (1983), Prussia, Anderson, & Manz (1998), and Houghton & Neck (2002). The instrument was composed of 18 items, with a 5-point Likert scale developed by Manz (1983) and modified by Kim (2002). Nurses' self-leadership was found to be related to job satisfaction, organizational commitment, nursing performance, and citizenship behavior. General characteristics of nurses, including age, education, marital status, position, and career, were also associated with self-leadership. Conclusion: The study findings provide data on recent trends in nurses' selfleadership. These results serve as basic data to provide a standard for developing self-leadership and indicate directions for further research.

• Journal of The Korea Institute of Healthcare Architecture
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• v.7 no.1
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• pp.45-55
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• 2001

In the 20th Century, the genera1 hospitals in Korea had changed in Qualitative and Quantitative aspects, The former would include such as the development of medical skills, equipments, and network system, The expansion of hospital space, increased numbers of hospitals and greater demands of medical attention from the public would be included in the latter, These various changes have been related to external forces such as the growth of the population, the changes in medical policy, the growth of G.N.P, the continuing discovery of new illnesses, the changes in architecture policy, and et cetera. Particularly, the hospitals built in 1970's and 80's have been expanded and renovated to cover the shortage of space, aged facilities, and the changes in hospital atmosphere. Thus, we hope that this study would provide appropriate data for master plans for new medical facilities as well as expansion and renovation data for old ones.

• The Journal of Bigdata
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• v.3 no.2
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• pp.123-130
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• 2018

As the demand for analytics technologies in both industry and academia increases, the demand for analytics experts is also increasing. To meet this trend, universities have begun to develop new analytics curriculum and provide courses for training analytics experts. In this study, we surveyed curriculum of master's analytics programs of 9 Korean universities and 20 overseas universities. As a result of comparing the domestic university program with the overseas university programs, the average number of subjects per school program is more than that of the Korean university program, but it was found to be less in terms of diversity of subjects.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.13 no.5
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• pp.113-127
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• 2003

WTLS as secure protocol of WAP makes TLS that is used in wireless Intemet protocol for TCP security be appropriate for wireless environments. And purpose of WTLS is to provide safe and efficient services. WTLS protocol consists of 4 protocols(Handshake, ChangeCipherSpec, Alert, Application Data etc.). In this papers we analyze properties of Handshake protocol and procedures of establishing master secret in detail. And then we analyze securities against several attacker models with them for a basis. Also we propose new Handshake protocol that is secure against active attacker model and can provide various security services.

• Journal of Distribution Science
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• v.19 no.7
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• pp.5-17
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• 2021

Purpose: The distribution of goods and the flow of information, determined by consumer behavior toward online shopping, is drastically popular worldwide. This study examines some factors such as brand trust, online sales promotion, consumer personality, delivery service, quality assurance, information search, and online consumer satisfaction influence online shopping behavior. Research design, data, and methodology: A constructed questionnaire in an online survey was conducted with 241 random cluster respondents in the greater Jakarta Area. Structure equation model was utilized to analyze and verify all the data. Results: Research finding indicates online sales promotion, delivery service, quality assurance, and online consumer satisfaction positively influence information search. Meanwhile, brand trust, quality assurance, and information search positively influence online shopping behavior. However, the result illustrates that consumer personality negatively influences both information search and online shopping behavior. Conclusions: To influence online shopping behavior, the most important factors that need to be considered by marketplaces are quality assurance. It positively motivates Indonesia's citizens to collect information and make unplanned purchases. The study finding can be a reference for brands to maintain and build outstanding product quality, an informational website, and an excellent marketing strategy so that customers can meet their expectations. Besides, it also broadens both companies' and individuals' knowledge about the digital revolution on consumer behavior.