• International Journal of Air-Conditioning and Refrigeration
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• v.10 no.1
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• pp.31-39
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• 2002

Microencapsulated pcm (MPCM) particles are mixed with distilled water and utilized to evaluate its characteristics and performance as a thermal storage medium transporting heat. For the present study, tetradecane ($C_14$$H_30$, $T_m$=5.5$^{\circ}C$) is capsulated in the core, coated with the melamine for their surface. The size of particles is well-controlled under 10$\mu$m in the process of in-situ polymerization with melamine-formaldehyde resin. For the experiment, the concentractions of slurries are prepared for 20 wt%, 30 wt%, and 40 wt%. The results are compared with those of water and 100% tetradecane oil. The pure water and tetradecane start solidifying within 20 minutes after introducing cooling water into the thermal storage tank whose flow rates are varied by 125 cc/min, 250 cc/min, and 500 cc/min. However, MPCM slurries are required relatively longer period of time for their phase change than pure phase change materials. That is, the entrained MPCM particles restrict their heat transfer in terms of natural convection and conduction to them.

• Review of KIISC
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• v.14 no.4
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• pp.68-77
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• 2004

국가 사회 각 분야(정부, 공공기관 및 민간기관)의 정보보호시스템에 의한 정보처리 의존도가 증가하고 있으며 정보보호 수준강화를 위한 평가업무의 수요 또한 늘어가고 있다. 이에 발맞추어 현재 정보보호시스템 평가에 대한 상호인증을 위해 공통평가기준(CC : Common Criteria)과 공통평가방법론(CEM : Common Evaluation Methodology)을 사용하고 있다. 본 논문에서는 정보보호시스템의 신뢰성의 확보와 상호인증을 위한 지침으로써 CC와 CEM에 대한 변화과정 및 특징을 분석하였으며 앞으로 이를 반영한 국제동향에 능동적인 대처와 효율적인 평가에 기여할 것으로 기대된다. 또한, 평가참여자(평가신청자, 개발자, 평가자, 감독자 등)의 역할도 변화의 흐름에 유연하게 대응해야 하며 이러한 지식을 토대로 객관적이며 체계적인 평가계획을 수립하는데 이용할 수 있을 것이다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.2
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• pp.80-87
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• 2001

Microencapsulated PCM particles are mixed with distilled water and utilized to evaluate its characteristics and performance as a thermal storage medium transporting heat. For the present study, tetradecane(C$_14H_30, T_m=5.5^{\circ}C$) is capsulated in the core with the melamine of its surface. The size of particles is well-controlled under 10${\mu}{\textrm}{m}$ in the way of in-situ polymerization with melamine-formaldehyde resin. For the experiment, the concentrations of slurries are prepared for 20wt%, 30wt%, and 40wt%. The results are compared with those of water and 100% tetradecane oil. The pure water and tetradecane start solidifying within 20 minutes after introducing cooling water into the thermal storage tank whose tank whose flow rates are varied by 125cc/min, 250cc/min, and 500cc/min. However, MicroPCM slurries are required relatively longer period of time for their phase change than pure phase change materials. That is, the entrained MicroPCM particles control its heat transfer in terms of natural convection and conducting to them.

• Journal of Digital Convergence
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• v.14 no.5
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• pp.341-348
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• 2016

Because VPN(Virtual Private Network) uses internet network, the security technique should support it and evaluation technique based on standard should support it. Therefore the method should be organized that can evaluate the security of VPN based on the related standard. In this study, we intended to construct the security evaluation model through combining CC(Common Criteria) which is a evaluation standard and a part of security(Confidentiality, Integrity, Non-repudiation, Accountability, Authenticity) evaluation of ISO which is the standard of software quality evaluation. For this, we analyzed the quality requirements about intra-technology and security of VPN and constructed the evaluation model related to the quality characteristics of two international standard. Through this, we are able to construct a convergence model for security evaluation of VPN. Through accumulating the evaluation practices for VPN in the future, the suitability and validity of the evaluation model must be improved.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3155-3158
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• 2013

Many published studies have concerned associations between the CYP1A2 -163 C>A polymorphism and risk of lung cancer, but the results have been inconsistent. Therefore, we performed a meta-analysis to obtain a more precise estimate. We searched the PubMed database up to March 1, 2013 for relevant cohort and case-control studies. Supplementary search was conducted manually by searching the references of the included studies and relevant meta-analyses. A meta-analysis was performed using RevMan 5.2 software for calculation of pooled odds ratios (ORs) and relevant 95% confidence intervals (CIs) after data extraction. Finally, seven case-control studies and one nested case-control study involving 1,675 lung cancer patients and 2,393 controls were included. The meta-analysis showed that there was no association of CYP1A2 -163 C>A polymorphism with risk of lung cancer overall [(OR=0.89, 95%CI= 0.74-1.07) for C vs. A; (OR=0.73, 95%CI= 0.50-1.07) for AA vs. CC ; (OR=0.82, 95%CI= 0.62-1.09) for AC vs. CC; (OR=0.79, 95%CI= 0.58-1.07) for (AC+AA) vs. CC; and (OR=0.87, 95%CI= 0.67-1.13) for AA vs. (CC+AC)]. Subgroup analysis indicated that there was an associationbetween CYP1A2 -163C>A polymorphism and lung cancer risk for population-based controls, a trend risk for SCCL (squamous cell carcinoma of lung) and Caucasians. These results suggested that -163 C>A polymorphism is likely to be associated with risk of lung cancer compared with population-based controls.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.14 no.2
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• pp.166-172
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• 2007

Purpose: The purpose of this study was to examine the factors influencing glass particle contamination in single dose glass ampules upon opening. Method: The study was single case experimental design. Different methods of opening ampule (hand, wooden stick), different sizes of ampules(1cc, 2cc) and different sizes of needles(17gauge, 23gauge, $5{\mu}m$ filter) were evaluated. Eighteen ampules were randomly assigned in each group. The number of glass ampule particles ${\ge}10{\mu}m$ was counted by microscope. Results: There was no significant difference in the number of particles aspirated by opening methods. But number of glass particles was much lower when using 1cc ampules rather than 2cc ampules and was also much lower when using smaller size needles and needles which include a $5{\mu}m$ filter rather than larger size of needles. Conclusion: We suggest that larger bore or unfiltered needles increase the risk of aspirating more glass particles than smaller bore or filter needles. In addition, these data show that a wooden stick can be used as a method opening glass ampules.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.685-690
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• 1999

The insulin like growth factors(IGFs) are bound to several binding proteins(IGFBPs) that appear to regulate IGF transfort, receptor binding, and its action. The concentrations of these peptides are regulated by quantity and nutritional quality of dietary proteins. The aim of this study was to compare the effects of two diets, which differed in their protein source, Carassius carassius(CC), Carassius carassius hot water extract(CCHE), for 4 weeks. Body weight was significantly increased in the CC group(74.14$\pm$12.00 to 266.31$\pm$36.62g; p<0.01). Likewise, IGF I concentration of CC group(101.76$\pm$15.90 ng/ml) was significantly higher than that of CCHE group(38.50$\pm$ 11.20ng/ml; p<0.05). By western immunoblot analysis, especially IGFBP 1, 2 levels are increased, whereas IGFBP 3 level was de creased in CCHE group. After extraction of browning material from each samples, the extractive was filtered and absorbance at 420nm was measured. The absorbance of CCHE group was significantly higher than that of CC group. These results suggest that IGF I can be employed as an index of protein metabolism, particulary as a simple index in the assessing the status of protein nutrition.

• Progress in Superconductivity and Cryogenics
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• v.23 no.1
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• pp.12-16
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• 2021

The magnetic properties of heat treated O-series high temperature superconducting (HTS) GdBCO coated conductor (CC) tapes which were formed of Ag/GdBCO/Buffer-layers/Stainless Steel (SS), were investigated by employing a Quantum Design PPMS-14. Using a modified Bean model, the critical current density J_c values have been estimated from the 𝚫m_irr(H) data, which are obtained by measuring the magnetic moment m(H) loops. For a range of intermediate fields, which are interacting or collective flux pinning area, the magnetic flux behaviors were investigated from the relationship J_c ∝ H^-β. In addition, the changes of irreversibility magnetic field H_irr line of heat-treated O-series HTS GdBCO CC tapes were analyzed, according as the annealing temperature under oxygen flowing increases. Both weak and strong break-downs were found by examining the changes of irreversibility magnetic field H_irr lines.

• Journal of Power Electronics
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• v.14 no.2
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• pp.302-314
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• 2014

Due to advancements in power electronics and inverter topologies, the current controlled multilevel voltage-source pulse width modulated (PWM) inverter is usually preferred for accurate control, quick response and high dynamic performance. A multilevel topology approach is found to be best suited for overcoming many problems arising from the use of high power converters. This paper presents a comprehensive review and comparative study of several current control (CC) techniques for multilevel inverters with a special emphasis on various approaches of the hysteresis current controller. Since the hysteresis CC technique poses a problem of variable switching frequency, a ramp-comparator controller and a predictive controller to attain constant switching frequency are described along with its quantitative comparison. Furthermore, various methods have been reviewed to achieve hysteresis current control PWM with constant switching frequency operation. This paper complies various guidelines to choose a particular method suitable for application at a given power level, switching frequency and dynamic response.

• Asia-Pacific Journal of Business
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• v.14 no.1
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• pp.21-39
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• 2023

Purpose - The purpose of this study is to confirm that five different working positions show different Organizational Commitment (OC) and factors influencing OC levels in the Chinese MNCs. Design/methodology/approach - The study collected data of 326 employees in different positions in Chinese MNCs abroad and in domestic country. To test hypotheses, ANOVA analysis and linearity regression are used with SPSS 26 and AMOS 26 software on the collected data. Findings - Results shows that different working groups do not show significant difference of AC and CC level. However, there are significant difference of NC among the five groups in the Chinese MNCs. Employee's position and marital status are positively related to CC and NC. Tenure is positively related to AC. Research implications or Originality - Our research offers insight for further research direction on OC difference research. It provides implication for Chinese MNCs to consider more about strategies how to stimulate host country employee's normative commitment.