• International Journal of Concrete Structures and Materials
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• 제5권2호
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• pp.113-117
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• 2011

The purpose of this work is the comparative study for grinding of two cement clinkers. X-ray fluorescence, physical and granulometric tests and optical microscopy were used to characterize the clinkers. Also grinding tests were carried out for ten samples to determine the parameters influencing grindability of its clinkers. The results of calculation of the energies of grinding according to the law developed by Von Rittinger and the study of the microstructure of the two clinkers shows good agreements. Indeed, frequent clusters of belite which indicate a lack of uniformity and fineness have an effect on lowering the grindability. The obtained analyses and the results enabled us to interpret the granulometry and the microstructure of clinker to control quality and resistance.

• Journal of Electrical Engineering and Technology
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• 제11권2호
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• pp.353-360
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• 2016

Series hybrid electric vehicles (SHEVs) having multiple power sources such as an engine- generator (EnGen), a battery, and an ultra-capacitor require a power control unit with high power density and reliable control operation. However, manufacturing using separate individual power converters has the disadvantage of low power density and requires a large number of power and signal cable wires. It is also difficult to implement the optimal power distribution and fault management algorithm because of the communication delay between the units. In order to address these concerns, this approach presents a design methodology and a power control algorithm of an integrated power converter for the SHEVs powered by multiple power sources. In this work, the design methodology of the integrated power control unit (IPCU) is firstly elaborately described, and then efficient and reliable power distribution algorithms are proposed. The design works are verified with product-level and vehicle-level performance experiments on a 10-ton SHEV.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.242-243
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• 2006

In this work, we report the synthesis and characterization of azomethineester polymers that consist of banana-shaped mesogen in their backbone. Two parts of the key structure of five-ring bent-core mesogen were modified by connecting different angle of central unit (Ar), and introducing lateral substituent into the outer ring (X). The synthetic details includes (1) placing the dioxydodecamethylene unit as a flexible spacer, (2) possessing 2,3- or 2,7-naphthylene, or 1,2-phenylene connection on the central unit, and (3) introducing fluorine or chlorine substituent (X = F or Cl) into the outer phenylene unit.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.171-174
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• 2006

In this work, we report the synthesis and characterization of azomethine-ester polymers that consist of banana-shaped mesogen in their backbone. Two parts of the key structure of five-ring bent-core mesogen were modified by connecting different angle of central unit (Ar), and introducing lateral substituent into the outer ring (X). The synthetic details includes (1) placing the dioxydodecamethylene unit as a flexible spacer, (2) possessing 2,3- or 2,7-naphthylene, or 1,2-phenylene connection on the central unit, and (3) introducing fluorine or chlorine substituent (X = F or Cl) into the outer phenylene unit.

• 간호행정학회지
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• 제19권5호
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• pp.578-588
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• 2013

Purpose: The purpose of this study was to identify the effects of bullying, negative affectivity and burnout in the nurses. Methods: The sample consisted of 389 nurses. Data were analyzed using frequency, percentage, mean, standard deviation, t-test, ANOVA, Scheff$\acute{e}$, Pearson Correlation Analysis and Hierarchical Multiple Regression. Results: The control variables of age, marital status, education level, current position, health status and work unit explained 30.2%(F=28.9, p<.001) of variance in burnout. The control variables, bullying and negative affectivity collectively explained 49.7% of variance in burnout. Conclusion: The results indicate that the demographic factors influencing burnout are age, education level, health status, work unit, while bullying and negative affectivity in the work places are factors that influence burnout. These findings can be utilized to develop strategies to reduce bullying and negative affectivity.

• 설비공학논문집
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• 제21권4호
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• pp.252-259
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• 2009

When various kinds of outputs are produced from a single energy system, the methodology which allocates the common cost to each output cost is very important because it is directly related with the profit and loss of producers and purchasers. In the cost allocation methodology of the heat and the electricity on a cogeneration, there are energy method, work method, proportional method, benefit distribution method, various exergetic methods, and so on. On the other hand, we have proposed a worth evaluation method which can be applied to any system. The definition of this methodology is that the unit cost of a product is proportion to the worth. Where, worth is a certain evaluating basis that can equalize the worth of products. In this study, we applied this methodology to a gas-turbine cogeneration which produces 119.2 GJ/h of electricity and 134.7 GJ/h of steam, and then we allocated 3,150 $/h of fuel cost to electricity cost and steam cost. Also, we compared with various cost allocation methods. As the result, we conclude that reversible work of various kinds of worth basis evaluates the worth of heat and electricity most reasonably.

• 중환자간호학회지
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• 제14권3호
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• pp.1-13
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• 2021

Purpose : This study aims to provide basic data for effective nursing interventions and improvement of nurses' work by exploring their work experiences in single-room-structured intensive care units (ICU) through focus group interviews. Methods : Data were collected through two focus group discussions conducted from March to November 2020 with 13 ICU nurses. Interviews were audio-recorded and analyzed thematically by investigators. Results : Through content analysis, 15 sub-categories and 6 categories were formed. Two themes, "positive experiences patients care in an independent space" and "difficulties in nursing work according to space separation of patients" emerged. There are positive aspects of single-room-structured ICUs, but it was found that practicing nurses had difficulties and required specialized nursing competencies. Therefore, efforts to reduce the burden of nurses in single-room-structured ICUs are necessary. Conclusion : The limitation of this study is that it was conducted in a single hospital because single-room-structured intensive care units are uncommon in Korea. However, this study is of great significance as a basis for establishing guidelines on the efforts required from nurses, hospitals, and governments single-room-structured ICUs in the future.

• Journal of Preventive Medicine and Public Health
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• 제28권3호
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• pp.623-639
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• 1995

We have never seen any method to cope basically with complicated situation and problems around medical reimbursement rates here in Korea since 1977 witnessed by the beginning of medical insurance. By the way researchers concerned are beginning to propose some kinds of innovative and detailed ideas to government these days. They are Diagnosis-related group(DRG) and Resource-based .elative value scale(RBRVS). In the light of this situation it is so encouraging that our government can come up with that and move. In case of RBRVS research we have already been reaching even to the level of reviewing and revising methodology for its further development after naive pilot study on internal medicine and general surgery last year. However there might be something different conditions between USA and Korea to apply the same Dr. Hsiao's method and it must be vital to check so called' total work approach' compared with 'intra-service work approach' before expanding to the whole medical fields. According to the' Intra-service approach', the physician's work is supposed to be divided into three sub-works by the name of intraservice work, pre, and post service work. These sub-works, again should be merged together to be the pre-postwork subset through some statistical methods of the estimation process applied by Dr. Hsiao's methodology in RBRVS development later on. But in this paper that estimation process was not taken because we could have real values for all of those surveyed items related to just one specialty, OB & GY. Instead, We used some statistical comparison procedures relevant to demographic characteristics, reliability & validity and correlation analysis with American RVU(Relative value unit) between the total work and merged total work from intraservice work approach. The unit of analysis was individual physicians of OB & GY and 300 physicians were selected for each approach through statistical sampling method based on national population of OB & GY physicians in Korea. And also with the thankful help of Advisory Committee under Korean Association of OB & GY, questionnaires were made and mailed to the subjects, two times. As a result there were not any statistically significant differences in demographic characteristics between the two approaches except for the variable 'Response time for the questionnaires', but in other sections of comparisons, response rate, representative values, reliability & validity test, correlation analysis with American RVU, all showed 'Total approach' was not only more rational and statistically meaningful than 'Intra-service approach' but also had considerable merits. But we are not absolutely sure about this paper's robustness. Because of some limitations, we'd rather like to suggest further researches should be followed. In that sense the first thing would be a research for the influence of doctor's characteristics, especially 'frequency' on the rating of work and the way to define total work more clearly.

• 정보통신설비학회논문지
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• 제2권4호
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• pp.52-63
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• 2003

This study proposes a change from the currentexpected price integrated system, which is based on the standard of estimated unit manpower and material, to a new actual construction cost integrated system. In order to implement it, the standard method of measurement organization system as well as the communication area standard of estimated unit manpower and material should be changed Moreover, the work breakdown structure and itemized structure should be assorted.

• Safety and Health at Work
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• 제11권3호
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• pp.378-379
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• 2020

Due to the significant methodological problems in the empirical part of the paper and the very selective literature review, the conclusions of the paper are mostly unsupported.