• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.4
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• pp.132-138
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• 2007

Experimental results of pulsating pressure behavior inside a chamber have been confirmed by computational work. Inside-cylinder pressure shows unstable condition at low rpm. This is caused by plate-type suction valve. It has effect up to inlet of the chamber. But trembling phenomenon is reduced as the pressure is enlarged by increasing the rpm. Result comparison between experimental and numerical analysis shows pulsation reduction is affected by the chamber. We can confirm that compressible effect of the working flow is shown at chamber inlet by increasing rpm. On the other side, this effect is declined at chamber outlet by increasing rpm. It means outlet pressure is going on balance with atmosphere pressure. Buffer plate-type chamber has efficiency of pulsation flow reduction.

• Journal of Korean Society on Water Environment
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• v.24 no.1
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• pp.44-53
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• 2008

To recognize the spatial and temporal variability of water temperature and dissolved oxygen in the Youngsan reservoir formed after dike construction, water temperature and dissolved oxygen data have been observed and analyzed from April, 2002 until March, 2003. As the results, certain stratifications were not distinctly observed in the Youngsan reservoir during summer, which was estimated due to the drainage characteristic from the Youngsan water gates. The yearly variation of water temperature in the Youngsan reservoir is shown seasonally ups and downs by the heat exchange between the atmosphere and the reservoir. On the other hand, dissolved oxygen and water temperature in the Youngsan reservoir have been shown inversed proportional correlation. As the calculation results of residence time and water exchange rate, it is considered that the feature of oxygen distribution is determined by the drainage characteristics caused the shortest residence time during summer, which also disturbed the formation of stratification in the Youngsan reservoir.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1247-1248
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• 2006

We fabricated YBCO film using a TFA-MOD method. In order to enhance the reaction kinetics and to control the formation of the second phases, $Y_2Ba_1Cu_1O_x$ and $Ba_3Cu_5O_8$ powders were used as precursors (the so called "211 process"). The films were calcined at $460^{\circ}C$ and then fired at $750^{\circ}C-800^{\circ}C$ in a 12.1% humidified $Ar-O_2$ atmosphere. We found that the microstructure varied significantly with the firing temperature. The textures of all of the films were similar and mainly biaxial. For the film fired at $775^{\circ}C$, the critical current was obtained to be 39 A/cm-width (corresponding critical current density is 2.0 MA/$cm^2$).

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.5
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• pp.446-452
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• 2013

Interest in the energy efficiency and carbon reduction technology is increasing. Many studies have done on the technologies of heat recovery systems, because over 30% of the total energy is released into the atmosphere with the exhaust gas flow. In this study, the Rankine cycle is analyzed in the optimum conditions given through the previous work. The result shows that the exergy efficiency is 0.53 and the output is 1.43 kW at the condition of the pressure ratio of 0.6 and the mass flow rate of 0.7.

• Culinary science and hospitality research
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• v.7 no.2
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• pp.99-121
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• 2001

To develop and improve as the finest foodservice industry, it has to secure the best team organized by the most satisfied employees. It is very important for foodservice industry to have the organization efficiency and study all kinds of factors to be influenced by several conditions. This study was focused on some matters to achieve the foodservice industry's business goal as well as to satisfy the employees. 1, the writer, set up four hypotheses for the examination. First, there will be not an interrelation between the employee's satisfaction and sex, age, marriage, educational background, and eager level. Second, there will be not an intreation between the employee's satisfaction and work period, position, department and major. This study could get some result from the analysis suggested by the above hypotheses. The following are the further explanation including some outstanding feature from the analysis based on the human resource: first for the category about the level of job satisfaction evaluated by the census, foodservice industry employee's job satisfaction depends upon the atmosphere in which employes could enjoy their work. Even the promotion chance can be made in the environment of creative and active working condition. Finally, the promotion chance can be realize not through the employee's attitude assuming the motivation factor to be difference from hygiene factor, but through keeping their work carried out in various activity.

• Journal of Engineering Education Research
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• v.12 no.3
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• pp.41-49
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• 2009

The paper introduces an educational environment for multidisciplinary automotive development project made with other global institutions worldwide. The main objective is to accelerate students design and manufacturing skills, while giving them the experience of global communications for a large scale collaboration. This objective demands the intimate partnership between industrial design and engineering worldwide as well. Not only is the design and manufacturing portion of the project a challenge, but the students must organize the project teams together to incorporate different subsystem designs from other institutions, which, after all, requires constant communication and a truly team-oriented atmosphere for the global innovative engineering education.

• Korean Journal of Hazardous Materials
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• v.6 no.2
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• pp.39-46
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• 2018

최근 전자제품 생산업체에서 EPS를 직접생산하게 되면서 EPS 공정이 증가하고 있다. EPS에는 펜탄이 포함되어 있으며, 펜탄은 하이브리드 혼합물로 구분할 수 있어 높은 화재폭발의 위험성을 가지고 있다. 각 공정별 펜탄의 누출률은 발포기, 사일로실, 저장실 순이나 발포기의 경우 일반적으로 밀폐되어 있으므로 사일로 실이 가장 화재폭발 위험성이 높다고 판단하였다. 사일로실의 누출률 중 70%는 사일로 상단을 통해 누출되며, 사일로 상단을 통해 누출되는 펜탄의 거동을 분석하여 사일로실 위험성 완화대책을 수립하였다. 1. 폭발위험구역 2종으로 관리, 2. 사일로상단 50cm이내 환기설비 설치 또는 Push-Pull 구조의 환기설비설치, 3. 사일로 하단 1.4m이내에 가스감지기 설치, 4. 60%이상의 습도유지

• Journal of Research and Publication Ethics
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• v.2 no.1
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• pp.1-6
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• 2021

The aims of this study were to examine the causes and types of the most common and serious fraudulent authors among research misconduct, and to examine ways to reduce the mass production of unjust authors. In scientific research, it is universal and efficient to have multiple authors participate. This is because each author group consisting of a team has its own expertise, and most of them participate in research in a complementary way to maximize the research effect. However, the competition for achievements between researchers, the quantitative evaluation system of universities, and the social atmosphere of performance-oriented are tempting researchers to abandon research ethics. In this study, in relation to the research ethics of existing researchers, the contents of research ethics by a few countries such as United States, United Kingdom, Germany, Canada, Australia etc. and the situation in Korea was examined as well. In addition, the types and causes of domestic unfair authors in Korea were investigated intensively. In conclusion, in order to no longer produce unfair authors such as compulsory authors, honorary authors, mutually supported authors, and duplicate authors, which researchers unknowingly recognize as co-authors, reinforcement of research ethics education and national organization and system should be supported.

• Journal of Korean Academy of Nursing
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• v.54 no.3
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• pp.340-357
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• 2024

Purpose: This study aimed to develop a Hybrid Clinical Practicum Environment Scale for Nursing Students (HCPES-NS) and verify its validity and reliability. Methods: The HCPES-NS was constructed following the DeVellis guidelines. The initial items were written based on a literature review and individual in-depth interviews. Content validity was verified through an expert panel review. To confirm the validity and reliability of the scale, a survey was conducted with 449 nursing students enrolled in 12 nursing colleges. Data were analyzed using item analysis, exploratory factor analysis, confirmatory factor analysis, concurrent validity, and reliability tests. Results: Factor analysis showed that the HCPES-NS consists of 15 items on five subdomains: clinical site atmosphere, interpersonal relationship, alternative online practicum contents, provision of learning information, and clinical performance facilitation. A higher score indicated a more positive perception of the clinical practicum environment. The concurrent validity of the HCPES-NS was confirmed by its positive correlation with the Clinical Learning Environment Scale (r = .77). The Cronbach's α reliability of the HCPES-NS was .84. Conclusion: The HCPES-NS is both valid and reliable. This scale reflects the clinical practicum environment and includes an online practicum factor. It may be used effectively by faculty members and educators to evaluate nursing students' perceptions of clinical practicum environments.

• Food Science and Preservation
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• v.21 no.6
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• pp.767-775
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• 2014

The shelf-life of fresh mushrooms is notably limited because their browning, texture change, and decay are too fast after immediately harvest. Especially, the best management for extending golden needle mushroom's shelf-life is modified atmosphere packaging under pressure vacuum at cold storage. In this study, three types of films, $20{\mu}m$ polyethylene+polypropylene (PE+PP), oriented polypropylene (OPP), and low density polyethylene (LDPE) were tested to extend the shelf-life of golden needle mushrooms. Mushrooms were packed under pressure vacuum and stored at $10^{\circ}C$ for 2 weeks. The golden mushrooms in LDPE film as a commercial packaging, were highly perishable and immediately proceed deterioration as browning, elongation, fluctuation of respiratory quotient (RQ) and softening within 7 days after packaging. On the other hand, the mushrooms in OPP and PE+PP film shown that shelf-life were extend to 14 days from 7 days, causing delay breakup of vacuum and maintenance of color, length, and RQ during storage. The breakup of vacuum in PE+PP film was faster few days than OPP film packaging. This present study indicated that the golden needle mushrooms by OPP packaging under pressure vacuum treatment might be extended the shelf-life until approximately 14 days during cold storage.