• Journal of the Institute of Electronics Engineers of Korea SD
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• v.48 no.10
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• pp.82-90
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• 2011

Because of the development of Smart phone devices, the demands of high performance FPU(Floating-point Unit) becomes increasing. Therefore, we propose the high-speed single-/double-precision FPU design that includes an elementary add/sub unit and improved multiplier and compare and convert units. The most commonly used add/sub unit is optimized by the parallel rounding unit. The matrix operation is used in complex calculation something like a graphic calculation. We designed the Multiply-Add Fused(MAF) instead of multiplier to calculate the matrix more quickly. The branch instruction that is decided by the compare operation is very frequently used in various programs. We bypassed the result of the compare operation before all the pipeline processes ended to decrease the total execution time. And we included additional convert operations that are added in IEEE754-2008 standard. To verify our RTL designs, we chose four hundred thousand test vectors by weighted random method and simulated each unit. The FPU that was synthesized by Samsung's 45-nm low-power process satisfied the 600-MHz operation frequency. And we confirm a reduction in area by comparing the improved FPU with the existing FPU.

• KEPCO Journal on Electric Power and Energy
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• v.3 no.2
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• pp.79-88
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• 2017

In this paper, the wind tunnel test for the measurement of aerodynamic characteristics of transmission conductors with asymmetric sections is described. A single conductor model and bundled conductor models with ice accreted shapes are tested both in steady and turbulent flow, and the aerodynamic coefficients are acquired. Transmission conductor galloping is a kind of wind-induced vibration which is characterized by primarily vertical oscillation with a very low frequency and a high amplitude. It is well known that transmission conductor galloping is generally caused by moderately strong, steady winds when a transmission conductor has an asymmetric cross-section shaped by accreted ice. Galloping should be considered from the design stage of overhead lines because it can cause severe wear and fatigue damage to attachments as well as transmission conductors. It is reported that there have been normally 20 events of galloping per year in Korea, which may be followed by serious consequences in the electric power system. Therefore, this research is performed to measure aerodynamic characteristics of ice accreted transmission conductors to understand and control transmission conductor galloping so that it would help to prevent unexpected failures and reduce the maintenance costs caused by galloping.

• Journal of The Korean Association For Science Education
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• v.31 no.4
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• pp.567-586
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• 2011

The purpose of this study was to investigate the gifted students' view on argumentation and the aspects of the argumentation in problem-solving type experiment. As a result, very lively argumentation was identified but quality enhancement on argumentation wasn't found over time. Students made frequent use of dialogic argumentation component, and especially, request & response component was highly used. Though usage frequency is low, the component of ground & question on ground was shown in 3rd class, and simple agreement gradually reduced, and reinforcing elaboration & metacognitive question has slightly increased. Also, students' argumentation were closely related to teachers' teaching approaches as some teacher-led steps doesn't appear in students' argumentation. By comparison in steps, 'problem solving activity & result analysis' step included 2 times more argument components than the previous step. We also found that method grouping teams does not almost affect the argumentation of gifted students. By survey results, most students recognized that they experienced free argumentation and this program activate argumentation and 'strange things' or 'difficulty' of program topics are obstacles in vitalization of argumentation. 'Surface growth experiments' was the most lively argumentation topic. The argumentation was lively made in the step of 'finding solution. 'Teachers' scaffolding accelerate the argumentation and help resolve difficulties in argumentation. Thus, students have positive recognition for the argumentation process in the experiments and recognize that argumentation process is needed.

• The Korean Journal of Community Living Science
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• v.20 no.3
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• pp.397-411
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• 2009

The use of local product foods and fresh-cut products, the dietitian's recognition, the required items and the quality for school foodservice was investigated to increase the consumption of high-quality agricultural products. Data from 578 elementary schools, 228 middle schools and 116 high schools were collected by school foodservice personnels in each regional Education Administration in Gyeong-gi province. The first criteria of buying food materials was reliability/safety for all school foodservice. The second criteria were the origin of the product and freshness/ripeness for elementary and middle schools and high school, respectively. The most important consideration for selecting a supplier was the quality of the material. The appearance/status of the food was the first factor for buying food materials. The origin and the seasonality were very important for buying farm products. Dietitians in Gyeong-gi province recognized the local products, and used them weekly. The advantages of using local products were the quick supply, freshness and safety. On the other hand, the disadvantages were the lack of information and the uncertainty of supply. Sixty eight percent of the subjects had experienced the high-quality agricultural products in school meals, but the frequency was low. The main reasons for not servicing high-quality agricultural products were the high cost and the lack of trust on the quality. Among fresh-cut products, seasonings and root vegetables were purchased most frequently, but leaf vegetables was 5.7% only. The purchase of fresh-cut products was not frequent, but usually satisfied. The advantages of fresh-cut products were the reduced workload and waste, but the reason for not using them were poor hygiene and the high price. The diverse supply system and the promotion of the local product foods would be necessary since the most food materials were purchased through suppliers. In addition, the problems related to the high cost and distrust should be resolved to expand the consumption of the high-quality agricultural products and the fresh-cut vegetables. The institutions for certifying the quality should be needed to increase the confidence of these products.

• Journal of Distribution Science
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• v.11 no.10
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• pp.47-53
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• 2013

Purpose - Six months have passed since the amendment of the SSM regulation law; however, as yet, there is no confirmed research or report on the effects of this amendment, which are indefinite. Further, there have been no attempts to study the effects of the SSM regulation law from the consumers' viewpoint, which is important because consumers are the main agents that are greatly influenced by the amendment law. Therefore, this study aims to investigate the consumers' attitude toward the SSM regulation law as well as the effects of the SSM regulation law on the changes in purchase behavior. Research design, data, and methodology - This study was initiated from four research problems that are linked to consumer reaction to the SSM regulation law. Research problem 1: What is the consumers' reaction (perception, attitude, and perceived fairness) to the SSM regulation law? Research problem 2: How do the consumers' reactions to the SSM regulation law differ by consumers' characteristics? Research problem 3: Could the SSM regulation law change a consumer's purchase behavior? Research problem 4: Is it necessary to amend the SSM regulation law? This study collected the data through the interview and survey of housewives for the purpose of solving the research problems. The interview was conducted as a pilot study for the field survey. We interviewed three housewives, who were: an employed housewife, a full-time homemaker, and a manager of a housewife club, respectively. We then conducted a field survey of 232 housewives who were housewife club members or elementary school parents in Chunghcheong-do. Results - We verified the reliability and validity of the data, and analyzed it to solve the research problems. The main findings of this study were as follows. First, consumers still have a positive attitude toward large discount chains and SSM, which has been the case since the law was introduced. Second, perceived risk of consumers associated with traditional markets and small neighborhood shops was low. Third, consumers think that amendments of the SSM regulation law are important, and they positively assess the satisfaction, necessity, and propriety of the law. Fourth, although the SSM regulation law caused inconvenience to consumers, this law did not have any influence on the usage frequency and the use-behavior of large discount chains. Finally, consumers reacted very negatively to the toughening up of the SSM regulation law. Conclusions - In short, consumers still have a positive attitude toward the SSM regulation law. However, this act did not have any influence on the use-behavior of large discount chains (General Super Market). Thus, policy making authorities require active communication and promotions to enhance the effect of the SSM regulation law. This study was of the nature of exploratory research, which did not focus on hypothesis testing, but on finding solutions to the research problems. Therefore, this study is no more than a simple data analysis. Future studies should attempt to investigate the actual effects of the SSM regulation law, on the basis of sufficient literature review and real sales data.

• Journal of Digital Convergence
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• v.15 no.5
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• pp.453-460
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• 2017

The purpose of this study was trying to figure out the effective employment guidance plan through employment preparation of graduating senior in department affiliated with physical education and recent situation. This study was compared to 2013 Graduates Occupational Mobility Survey(GOMS). Data were collected from 164 graduating seniors in the department affiliated with physical education from 5 institutions of a 4-year university located in Gyeonggi-do, Seoul, and ChungChong-do by convenience sampling. For the data analysis, a descriptive statistic, frequency analysis, and one-samples t-test were conducted. Graduating seniors participating in school employment programs had a lower rate but the average rate of participation in career & employment classes and vocational test was more than 50%. They were satisfied with university education and career support but employment program and welfare facilities are in need of improvement. Furthermore, graduating seniors have national and private certificates related to major. Finally, they have very low participation rates in youth employment policies of government. Based on the results, the effective job placement guideline for the department affiliated with physical education is needed.

• Korean Journal of Hospice Care
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• v.7 no.1
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• pp.15-28
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• 2007

This study was focused on figure out what kinds of elements are influencing on job satisfaction with approach of the educational system. It was also to figure out how work characteristics and role conflicts of employees influence on job satisfaction. Objects of study were employeeswho had been working in Hospice and Palliative medical center at least for 6 months, and they were doctors, nurses, ministers, and welfare workers. Collected materials were analyzed by Frequency Analysis, One-way ANOVA, Correlation Analysis, and SimpleRegression Analysis. Results from study can be summarized like below. The first, job satisfaction of workers in Hospice and Palliative medical center were 3.36, and this numerical value is pretty high over all. For saying from the higher to the lower satisfaction level, there were satisfaction with job itself, satisfaction with co-workers, satisfaction with seniors (superiors), and satisfaction with organizations, on the other hands, satisfaction with salaries was turned out as the lowest level among those. The second, role conflict was 2.63, and it is considered as the medium level. after inquiring into it by elements of role conflict, they felt many environmental difficulties compared to other workers in different fields such as environmental difficulty, role ambiguity, insufficient ability, process obscurity, etc. The third, work environment influencing on job satisfaction are as follows. Professional environment among characteristics of work environment was significant statistically. Job satisfaction of ministers was the highest; others were in the order of doctors, welfare workers, and nurses. For employment history, job satisfaction was higher as they have more and longer job experience including whole professional experience both in hospice and palliative medical center. In addition, participating in hospice and palliative programs, intensive training regularly was significantly. Job Motivation was also significant statistically. Especially, job satisfaction was higher when people decided to work in hospice and palliative medical center because of individual desire (self-realization). Lastly, influence of role conflict on job satisfaction is as follows. Environmental difficulty, role ambiguity, insufficient ability, process obscurity, etc showed the significant meaning statistically, and the lower role conflict was related with the higher job satisfaction. Suggestions for next study based on such results are as follows in order to improve or increase job satisfaction of employees in hospice/palliative medical centers. The first, to expand education opportunity of employees is needed to increase job satisfactionof hospice/palliatives medical centers. Participating in intensive programs and seminars by types of occupation and acquiring professional knowledge are very important since employees are motivated by those activities. For that, developing and activating intensive education/programs by professional occupations are suggested. The second, dividing roles of employees and determining each job's limit clearly in hospice/palliative medical centers are required. For that, study developing standard job regulations is suggested for each professional job. Lastly, developing and providing reasonable salaries is needed because low salaries of hospice/palliative medical centers are the absolute reason lowering job satisfaction. Therefore, this paper suggests improving the salary level of employees of hospice/palliative medical centers and developing practical plan for it.

• The Korean Journal of Applied Statistics
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• v.30 no.6
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• pp.917-929
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• 2017

Korean income data obtained from Korea Labor Panel Survey shows excessive zeros, which may not be properly explained by the Tobit model. In this paper, we analyze the data using a zero-inflated Tobit model to incorporate excessive zeros. A zero-inflated Tobit model consists of two stages. In the first stage, individuals with 0 income are divided into two groups: genuine zero group and random zero group. Individuals in the genuine zero group did not participate labor market since they have no intention to do so. Individuals in the random zero group participated labor market but their incomes are very low and truncated at 0. In the second stage, the Tobit model is assumed to a subset of data combining random zeros and positive observations. Regression models are employed in both stages to obtain the effect of explanatory variables on the participation of labor market and the income amount. Markov chain Monte Carlo methods are applied for the Bayesian analysis of the data. The proposed zero-inflated Tobit model outperforms the Tobit model in model fit and prediction of zero frequency. The analysis results show strong evidence that the probability of participating in the labor market increases with age, decreases with education, and women tend to have stronger intentions on participating in the labor market than men. There also exists moderate evidence that the probability of participating in the labor market decreases with socio-economic status and reserved wage. However, the amount of monthly wage increases with age and education, and it is larger for married than unmarried and for men than women.

• Fire Science and Engineering
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• v.31 no.6
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• pp.67-73
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• 2017

An aircraft maintenance hangar is a building that stores, maintains, and inspects expensive aircraft. The frequency of fire occurrence is low, but the resulting human and material damage can be very serious. Therefore, in this study, we conducted a qualitative analysis of the fire safety of the currently operating fire suppression systems for aircraft maintenance hangars using the Fault Tree method, and then performed a quantitative analysis using the failure rate data for the derived basic events and analyzed the importance of the minimal cut sets. As a result of the qualitative analysis by the minimal cut set, it was found that there were 14 accident paths that could be expanded to a large fire, due to the fire control failure of the aircraft hangar fire suppression system. The quantitative analysis revealed that, the probability of the fire expanding into a large one is $2.08{\times}E-05/day$. The analysis of the importance of the minimal cut set shows that four minimal cut sets, namely the fire detector and foam head action according to the zone and blocking of the foam by the aircraft wing and the fire plume, had the same likelihood of causing the fire to develop into a large one, viz. 24.95% each, which together forms the majority of the likelihood. It was confirmed for the first time by fault tree method that the fire suppression system of aircraft maintenance hangars is not suitable for fires under the aircraft wings and needs to be improved.

• Journal of Korean Society of Transportation
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• v.35 no.5
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• pp.396-408
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• 2017

In Korea, the number of elderly has been increasing rapidly. So it is also expected that the economic activity and the trip frequency of the elderly will increase. On the other hand, elderly related accidents such as falls during walking are steadily increasing and the satisfaction about pedestrian environment of elderly is very low. In this paper, we found one of the reasons for these dissatisfaction in pedestrian facility, which is not considering the walking ability (about 75% of non-elderly person) of the elderly. So, we analyze the kinematic walking characteristics of the elderly with the motion analysis system, when the elderly use stairs. As a result of analysis of various walking variables, the current standard for stairway height in Korean law (18cm) requires excessive force to elderly so it was difficult for elderly to keep the balance of the body in ascending and descending walk of stairs. In this paper, we propose the stair design criteria through the cluster analysis of walking parameters reflecting the gait characteristics of the elderly. This change is not a big for non-elderly person, but it can promote more socioeconomic activities for the elderly.