• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.4B
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• pp.368-376
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• 2009

Over recent years, the development of multimedia devices has meant that a wider multimedia streaming service can be supported, and there are now many ways in which TV channels can communicate with different terminals. Generally, scalable video streaming is known to provide more efficient channel capacity than simulcast video streaming. Simulcast video streaming requires a large network bandwidth for all resolutions, but scalable video streaming needs only one flow for all resolutions. On the contrary, to preserve the same video quality, SVC(Sealable Video Coding) needs a higher bit-rate than AVC(non-layered Video Coding) due to the coding penalty($10%{\sim}30%$). In previous research, scalable video streaming has been compared with simulcast video streaming for network channel capacity, in two-user simulation environments. The simulation results show that the channel capacity of SVC is $16{\sim}20%$ smaller than AVC, but scalable video streaming is not efficient because of the limit of the present network framework. In this paper, we propose a new network framework with a new router using EDE(Extraction Decision Engine) and SVC Extractor to improve network performance. In addition, we compare the SVC environment in the proposed framework with previous research on the same way subject. The proposed network framework shows a channel capacity 50%(maximum) lower than that found in previous research studies.

• Korean Chemical Engineering Research
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• v.57 no.1
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• pp.51-57
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• 2019

A plant layout problem has a large impact on the overall construction cost of a plant. When determining a plant layout, various constraints associating with safety, environment, sufficient maintenance area, passages for workers, etc have to be considered together. In general plant layout problems, the main goal is to minimize the length of piping connecting equipments as satisfying various constraints. Since the process may suffer from the heat and friction loss, the piping length between equipments should be shorter. This problem can be represented by the mathematical formulation and the optimal solutions can be investigated by an optimization solver. General researches have overlooked many constraints such as maintenance spaces and safety distances between equipments. And, previous researches have tested benchmark processes. What the lack of general researches is that there is no realistic comparison. In this study, the plant layout of a real industrial C3MR (Propane precooling Mixed Refrigerant) process is studied. A MILP (Mixed Integer Linear Programming) including various constraints is developed. To avoid the violation of constraints, penalty functions are introduced. However, conventional optimization solvers handling the derivatives of an objective functions can not solve this problem due to the complexities of equations. Therefore, the PSO (Particle Swarm Optimization), which investigate an optimal solutions without differential equations, is selected to solve this problem. The results show that a proposed method contributes to saving the capital expenditures.

• Korean Chemical Engineering Research
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• v.61 no.2
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• pp.208-216
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• 2023

In this study, using the Delphi method, 20 responses to 4 questions (need for launch safety control, top-priority considerations for ensuring public safety during launch, necessary improvements for securing maritime safety, and maritime safety threat factors) regarding launch vehicles and public safety were obtained from experts, and their importance was evaluated to analyze the factors that threaten the reinforcement of maritime safety around launch sites and flight paths when launching. According to the results of an analytic hierarchy process (AHP) analysis, the consistency ratio of the four questions was 4.8%, which is lower than CR ≤ 0.1(10%), and the consistency percentage of the lower measurement indicators was 3.9~5.7%. The derived importance and priority of maritime safety threat factors during launching were in the following order: Substantial human and physical damage in case of launch accidents(0.36), Prepare legal bases (e.g., penalty details) regarding maritime control(0.32), Secure the safety of personnel, equipment, and facilities in danger zone(0.31), Unauthorized entry of vessels in maritime control zones and non-compliance to restrictions(0.30). This article can serve as a reference for strengthening maritime safety in areas around launch sites and flight paths.

• Korean Chemical Engineering Research
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• v.50 no.2
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• pp.365-370
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• 2012

In this study, Economic analysis of supercritical coal-fired power plant with $CO_2$ capture process was performed. For this purpose, chemical absorption method using amine solvent, which is commercially available and most suitable for existing thermal power plant, was studied. For the evaluation of the economic analysis of coal-fired power plant with post-combustion $CO_2$ capture process in Korea, energy penalty after $CO_2$ capture was calculated using the power equivalent factor suggested by Bolland et al. And the overnight cost of power plant (or cost of plant construction) and the operation cost reported by the IEA (International Energy Agency) were used. Based on chemical absorption method using a amine solvent and 3.31 GJ/$tonCO_2$ as a regeneration energy in the stripper, the net power efficiency was reduced from 41.0% (without $CO_2$ capture) to 31.6% (with $CO_2$ capture) and the levelized cost of electricity was increased from 45.5 USD/MWh (Reference case, without $CO_2$ capture) to 73.9 USD/MWh (With $CO_2$ capture) and the cost of $CO_2$ avoided was estimated as 41.3 USD/$tonCO_2$.

• The Korean Journal of Elementary Counseling
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• v.9 no.2
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• pp.175-193
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• 2010

The aim of this study is to examine effects of a yoga program for children on school stress of the elementary school children. To achieve this goal, total 10 students out of 231 in 6 classes among the third graders in M elementary school in B city were selected as subjects for this study. After regular school hours, they participated in a children's yoga program for 16 times for 45 minutes per session in the course of 8 weeks. An ethnographic interview was conducted to identify the effects of the program. During the initial stage of the children's yoga program, the participants were interviewed preliminarily. An analysis of areas and an analysis of classifications were made based on the initial interview results, and an area classification table was drawn on the school stress perceived by the elementary school children. After the yoga program ended, a follow up interview was made to apply an analysis of components by comparing changes in the school stress level due to a yoga effect. A research report was written through a cycle of addition and supplement in which the previous data analysis was complemented and corrected by new findings of the study. As a result of the ethnographic interview to analyze the school stress perceived by the elementary school children, and an examination of the changes in the school stress level, the children's yoga program proved to be significantly effective in reducing the school stress. However there were limitations to a certain degree in stress reduction. Details of such findings in each sub-category are as follow. First, as a result of the initial interview analysis, the school stress was classified broadly into 4 categories of study stress, friendship stress, teacher stress, and school environment stress. Second, the study stress as the first category of the school stress was classified into 3 sub-categories of homework, class, and exam stresses. In spite of minor differences among 3 sub-categories, the stress was reduced in general. Third, the friendship stress as the second category of the school stress was also classified into 3 sub-categories of bullying, alienation, and performing one's duty. There were minor differences among sub-categories, however stress reduction also appeared with the exception of the performing one's duty category which had relatively little effect from the yoga program. Fourth, regarding the teacher stress as the third school stress, a classification was made into 3 sub-categories of preference, penalty, and teaching method. Minor differences among the 3 sub-categories notwithstanding, stress reduction appeared with the exception of the teaching method stress which had relatively little effect from the yoga program. Fifth, the school environment stress as the fourth category of the school stress was classified into 2 sub-categories of school meals and facilities. Minor differences between the 2 categories notwithstanding, stress reduction appeared with the facilities stress having relatively little effect.

• Journal of Korean Academy of Nursing Administration
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• v.2 no.1
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• pp.97-114
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• 1996

INSTRODUCTION Service quality is, unlike goods quality, an abstract and elusive constuct. Service quality and its requirements are not easily understood by consumers, and also present some critical research problems. However, quality is very important to marketers and consumers in that it has many strategic benefits in contributing to profitability of marketing activities and consumers' problem-solving activities. Moreover, despite the phenomenal growth of medical service sector, few researchers have attempted to define and model medical service quality. Especially, little research has focused on the evaluation of medical service quality and patient satisfaction from the perspectives of both the provider and the patient. As competition intensifies and patients are demanding higher quality of medical service, medical service quality and patient satisfaction has emerged as a critical research topic. The major purpose of this article is to explore the concept of medical service quality and its evaluation from both nurse and patient perspectives. This article attempts to achieve its purpose by (1)classfying critical service attibutes into threecategories(satisfiers, hygiene factors, and performance factors). (2)measuring the relative importance of need criteria, (3)evaluating SERVPERF model and SERVQUAL model in medical service sector, and (4)identifying the relationship between perceived quality and overall patient satisfaction. METHOD Data were gathered from a sample of 217 patients and 179 nurses in Seoul-area general hospitals. From the review of previous literature, 50 survey items representing various facets of the medical service quality were developed to form a questionnaire. A five-point scale ranging from "Strongly Agree"(5) to "Strongly Disagree"(1) accompanied each statement(expectation statements, perception statements, and importance statements). To measure overall satisfaction, a seven-point scale was used, ranging from "Very Satisfied"(7) to "Very Dissatisfied"(1) with no verbal labels for scale points 2 through 6 RESULTS In explaining the relationship between perceived performance and overall satisfaction, only 31 variables out of original 50 survey items were proven to be statistically significant. Hence, a penalty-reward analysis was performed on theses 31 critical attributes to find out 17 satisfiers, 8 hygiene factors, and 4 performance factors in patient perspective. The role(category) of each service quality attribute in relation to patient satisfaction was com pared across two groups, that is, patients and nurses. They were little overlapped, suggesting that two groups had different sets of 'perceived quality' attributes. Principal components factor analyses of the patients' and nurses' responses were performed to identify the underlying dimensions for the set of performance(experience) statements. 28 variables were analyzed by using a varimax rotation after deleting three obscure variables. The number of factors to be extracted was determined by evaluating the eigenvalue scores. Six factors wereextracted, accounting for 57.1% of the total variance. Reliability analysis was performed to refine the factors further. Using coefficient alpha, scores of .84 to .65 were obtained. Individual-item analysis indicated that all statements in each of the factors should remain. On 26 attributes of 31 critical service quality attributes, there were gaps between actual patient's importance of need criteria and nurse perceptions of them. Those critical attributes could be classified into four categories based on the relative importance of need criteria and perceived performance from the perspective of patient. This analysis is useful in developing strategic plans for performance improvement. (1) top priorities(high importance and low performance) (in this study)- more health-related information -accuracy in billing - quality of food - appointments at my convenience - information about tests and treatments - prompt service of business office -adequacy of accommodations(elevators, etc) (2) current strengths(high importance and high performance) (3)unnecessary strengths(low importance and high performance) (4) low priorities(low importance and low performance) While 26 service quality attributes of SERPERF model were significantly related to patient satisfation, only 13 attributes of SERVQUAL model were significantly related. This result suggested that only experience-based norms(SERVPERF model) were more appropriate than expectations to serve as a benchmark against which service experiences were compared(SERVQUAL model). However, it must be noted that the degree of association to overall satisfaction was not consistent. There were some gaps between nurse percetions and patient perception of medical service performance. From the patient's viewpoint, "personal likability", "technical skill/trust", and "cares about me" were most significant positioning factors that contributed patient satisfaction. DISCUSSION This study shows that there are inconsistencies between nurse perceptions and patient perceptions of medical service attributes. Also, for service quality improvement, it is most important for nurses to understand what satisfiers, hygiene factors, and performance factors are through two-way communications. Patient satisfaction should be measured, and problems identified should be resolved for survival in intense competitive market conditions. Hence, patient satisfaction monitoring is now becoming a standard marketing tool for healthcare providers and its role is expected to increase.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.1 no.1
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• pp.73-82
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• 2000

Conventional funding system for the university research projects is limited to a grant or subsidy type funding method which does not require an obligation of refund. Such a funding system is known as ideal one for the university research activities which in general is not a profit oriented activities. It is considered ideal in a sense that nonprofit oriented research activities gives more emphasis on creativity than on efficiency or practical value. A venture- business-start-up research activity can not be considered as a pure nonprofit oriented activities. It clearly gives more emphasis on efficiency and practical value than on creativity Recently a large portion of the venture-business-start-up research activities are carried out in the universities. When a conventional research funding system is applied to such a new type of research activities, it turned out that the success rate is much lower than expectancy. This is why a new and differentiated funding system is sought for such a new type of research activities. A funding system of loan type for a venture-business-start-up research activities is proposed herewith. A loan system naturally requires a pay back after the successful start up of the venture business. This loan system nay be considered that a business concept is grafted on a conventional funding system for the university research activities. This means that a rather loose or generous terms and conditions of the money loan case is introduced into this funding system to remedy the short comings of the intrinsic nonprofit nature of the university research activities. The point is how to improve the success rate and how to reduce the undesirable aspect of the conventional university research activities when it is practiced with the new type of research activities. After one and half year of practicing with the new funding system. it can not be asserted that a definitely positive results could be obtained. but a trend of desirable aspects could be observed such as low drop out rate. project selection efficiency, higher sense of responsibility. etc.