• Title/Summary/Keyword: dual problems

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2-D Periodic Unsteady Flow Analysis Using a Partially Implicit Harmonic Balance Method (부분 내재적 조화 균형법을 이용한 주기적인 2차원 비정상 유동 해석)

  • Im, Dong-Kyun;Park, Soo-Hyung;Kwon, Jang-Hyuk
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.38 no.12
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    • pp.1153-1161
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    • 2010
  • An efficient solution method for harmonic balance techniques with Fourier transform is presented for periodic unsteady flow problems. The present partially-implicit harmonic balance treats the flux terms implicitly and the harmonic source term is solved explicitly. The convergence of the partially Implicit method is much faster than the explicit Runge-Kutta harmonic balance method. The method does not need to compute the additional flux Jacobian matrix from the implicit harmonic source term. Compared with fully implicit harmonic balance method, this partial approach turns out to have good convergence property. Oscillating flows over NACA0012 airfoil are considered to verify the method and to compare with results of explicit R-K(Runge-Kutta) and dual time stepping methods.

A Study on the Privatization of School Facilities Maintenance (학교시설유지관리의 민간위탁에 관한 연구)

  • Cho, Chang-Hee;Lee, Hwa-Ryong
    • Journal of the Korean Institute of Educational Facilities
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    • v.15 no.2
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    • pp.39-49
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    • 2008
  • School facilities maintenance is concerned about providing clean and safe environments for children. It is also about creating a physical setting that is appropriate and adequate for learning. But many of the school buildings in Korea have been maintained and operated by each school manger or pubic officers in the Educational Department. This system could not extend the life of building components, keep equipment functioning as designed or sustain a sage and healthful environment because of its non-professionality and the dual fiscal system. In order to improve such problems, it is proposed to privatize the maintenance of school building. It is sure that the new way to outsource services reduce costs and provide high quality services. Competitive contracting with the private sector can provide schools with expertise, flexibility and cost efficiencies as well as help school administrators focusing on educating the children. This study explores the maintaining status of existing schools, analyses the cases about BTL schools and the foreign country's policies and surveys the outsourcing cases of Kyungki-do schools. Finally it proposes more appropriate plans for privatizing the maintenance way of school building in Korea.

Consumer Segmentation of Clothing Products by Fashion Conformity/Innovativeness and Their Reference Groups (유행동조성과 혁신성에 따른 소비자 세분화 및 준거대상 연구)

  • 김한나;이은영
    • Journal of the Korean Society of Clothing and Textiles
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    • v.25 no.7
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    • pp.1341-1352
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    • 2001
  • When segmenting consumers according to their fashion adoption behavior, it has been assumed that consumers' fashion conformity and innovativeness characteritics are negatively correlated. The purpose of this study was to examine the relationship between conformity and innovativeness and that these two attributes exist independently. The research problems of this study were to segment consumers according to the degrees of conformity and innovativeness, and to identify differences in reference groups and clothing purchasing behavior among the segments. The results of the empirical study showed that the fashion conformity and innovativeness were in and innovativeness; High conformity/High innovativeness group(HC/HI), High conformity/Low innovativeness group (HC/LI), Low conformity/High innovativeness group(LC/HI?, and Low conformity/Low innovativeness group (LC/LI). When the groups were compared in their reference groups and purchasing behavior, it was found out that HC groups were more influenced by reference groups than LC groups. When HC/LI and HC/HI groups were compared, HC/LI group was more influenced by their parents and siblings, while HC/HI group was more influenced by upper class and celebrities. Both groups were mostly influenced by friends and desirable passengers on the street. Friends and passengers were most influential to LC groups also, even though they were less influenced than HC groups. In conclusion, the fashion conformity and innovativeness were found to exist in different dimensions consisting dual structure. Thus, retailers and marketers can make their strategies more successfully if they use these two characteristics separately when segmenting consumers.

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Inedible Vegetable Oil as Substitute Fuel in Compression Ignition Engines-Jatropha Oil

  • No, Soo-Young
    • Journal of ILASS-Korea
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    • v.14 no.4
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    • pp.153-162
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    • 2009
  • The use of inedible vegetable oils as substitute for diesel fuel in compression ignition engine is of significance because of the great need for edible oil as food, and the reduction of biodiesel production cost etc. Jatropha curcas oil which is a leading candidate for the commercialization of inedible vegetable oils is selected in this study for reviewing the application in CI engine as an alternative fuel. The important properties of jatropha oil (JO) and JO biodiesel are summarized from the various sources in the literature. It is found that five different types of alternative fuel from JO such as neat JO, JO blends with diesel or other fuel, neat JO biodiesel, JO biodiesel blends with diesel or other fuel and degummed JO were extensively examined in the diesel engine. Two different application types of alternative fuels from JO such as preheating and dual fuelling were also tested, It should be pointed out that most of these applications are limited to single cylinder conditions. The systematic study for the selection of effective application method is required. It is clear that the blends of JOME and diesel can replace diesel fuel up to 10% by volume for running the existing common rail direct injection systems without any durability problems. The systematic assessment of spray characteristics of different types of JO and its derivatives for use as diesel engine fuel is also required.

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A Study on Actual Footwear-wearing Conditions of College Students in Kwangju & Jeonam (광주, 전남지역 대학생의 신발착용 실태에 관한 연구)

  • Jeong, Young-Ok
    • The Korean Journal of Community Living Science
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    • v.22 no.3
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    • pp.365-377
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    • 2011
  • The dual purposes of this study were to investigate footwear worn by college students who have become spoilt for choice in apparel & shoes, and point out the problems of their shoe-wearing habbits. The survey was administered in October, 2010 to 600 college residents in Kwangju-Jeonnam area and the results are as follows. Firstly, the most frequently worn footware by males were sneakers, followed by dress shoes and oxford shoes. Females followed a similar trend with sneakers being the most frequently worn, followed by high heeled shoes, flat shoes, wedge high heeled shoes and chucker boots. Secondly, both male and female students thought that the most comfortable and favorable shoes for them were sneakers and the most uncomfortable ones were high-heeled shoes and sandals. They thought chucker boots were both fashionable and comfortable. Thirdly, the degree of unsatisfaction for shoes was relatively high and the influencing factors for unsatisfaction were uncomfortable soles, aches around the toes and a frontward leaning posture of the body, etc. Finally, 87% of the female subjects who had experience wearing high-heeled(over 7cm height) shoes showed a significant increase in foot disorders than those who had never worn high-heeled shoes. According to the results, it is necessary to educate proper selection and wearing of footwear in order to prevent foot disorders and maintain overall health of the body.

The Derailment Safety Estimation of DMT Freight for Real Track Condition (실제 선로조건에 따른 DMT 화차의 탈선안전도 평가)

  • Son, Myoung-Sun;Eom, Beom-Gyu;Lee, Hi-Sung
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.21 no.7
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    • pp.637-642
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    • 2011
  • The DMT freight is judged that economic performance is good because can increase cargoes than existing freight. However, the existing freight cars, each with a different balance to the body structure is bogie because the vibrations may occur. Thus, by minimizing vibration over the existing freight securing the safety of the driving if you will not have major problems in cargoes. In this study, multi-body dynamic analysis tool, VI-Rail using the actually Gyeongbu Railroad line and an empty, full freight condition include curve radius, track irregularity, The DMT freight of the derailed wagons were assessed for safety analysis. Full and empty freight conditions for parity in the Gyeongbu Railroad line(Dongdaegoo${\leftrightarrow}$Kyungsan) derailment safety analysis, such as derailment coefficient and the wheel unloaded, echoing the curve and the orbit is affected by the irregularity was found. Full freight condition than the empty conditions showed a significant derailment safety. Overall, the limits of derailment coefficient(Q/P = 0.8) and wheel unload decrement limits(${\triangle}P/P$ = 0.6) is less safe with me confirmed that the derailment safety.

Combined Effects of Multiple Endoplasmic Reticulum Stresses on Cytokine Secretion in Macrophage

  • Kim, Hye-Min;Do, Chang-Hee;Lee, Dong-Hee
    • Biomolecules & Therapeutics
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    • v.20 no.3
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    • pp.346-351
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    • 2012
  • Cells show various stress signs when they are challenged with severe physiological problems. Majority of such cellular stresses are conveyed to endoplasmic reticulum (ER) and unfolded protein response (UPR) serves as typical defense mechanism against ER stress. This study investigated an interaction between ER stress agents using macropage cell line Raw 264.7. When activated by lipopolysaccharide (LPS), the cell lines showed typical indicators of ER stress. Along with molecular chaperones, the activation process leads to the production of additional inflammatory mediators. Following activation, the macrophage cell line was further treated with TUN and characterized in terms of chaperone expression and cytokine secretion. When treated with TUN, the activated macrophage cell leads to increased secretion of IL-6 although expression of ER stress markers, GRP94 and GRP78 increased. The secretion of cytokines continued until the addition of BFA which inhibits protein targeting from ER to Golgi. However, secretion of cytokines was ceased upon dual treatments with BFA and TG. This result strongly implies that cells may differently deal with various polypeptides depending on the urgency in cellular function under ER stress. Considering IL-6 is one of the most important signal molecules in macrophage, the molecule might be able to circumvent ER stress and UPR to reach its targeting site.

Effects of the Early Sensorimotor Training on Vastus Medialis Oblique Muscle Activation in Patients after Partial Medial Meniscectomy

  • Jeong, Dawoon;Hwangbo, Gak
    • Journal of International Academy of Physical Therapy Research
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    • v.11 no.1
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    • pp.1969-1974
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    • 2020
  • Background: Early rehabilitation after partial meniscectomy is important to recover the balance of the vastus medialis oblique and vastus lateralis and prevent pathological problems in the lower extremities and the whole body. Objective: To compare muscle activations for patients after partial meniscectomy. Design: Dual-group Pretest-Posttest Design from the Quasi-Experimental Research. Methods: Twenty participants after partial meniscectomy were recruited and were randomly divided into a Q-setting sensorimotor training group (QSMTG) and Q-setting exercise group (QSEG). Muscle activity of the vastus medialis oblique and vastus lateralis was measured before and after intervention. Results: In the two groups, the vastus medialis oblique and vastus lateralis activations increased significantly (P<.05). The Q-setting sensorimotor training group showed more increases than the Q-setting exercise group, and there were significant differences between the groups (P<.05). The activation ratio of the vastus medialis oblique and vastus lateralis had increasingly significant differences in the Q-setting sensorimotor training group (P<.05), and there were no significant differences between the groups (P>.05). Conclusion: Q-setting exercise with sensorimotor training was a useful method that improved the balance of vastus medialis oblique (VMO) and vastus lateralis (VL) activity after meniscectomy.

A study on Language Environment and Korean Language Education problems in Sakhalin, Russia (러시아 사할린 지역의 언어 환경과 한국어교육 문제 연구)

  • Cho, Hyun Yong;Lee, Sang Hyeok
    • Journal of Korean language education
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    • v.23 no.1
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    • pp.257-282
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    • 2012
  • Sakhalin, Russia is a very specific area for Korean language education. The imposed separation and isolation in this region means the language in Sakhalin is mixed with South Korean, North Korean, Gyeongsang Province dialect, Japanese, and Russian. Scrutiny of the use of the actual language of Sakhalin Koreans is needed, and it is required in supporting Korean language education. In this study, I will cover: 1. Approach should differ depending on the situation of Korean, foreigners, Korean Language School(Hangeul Hakgyo) and Korean classes in local Schools. 2. Tailor-made textbooks for Sakhalin are required. 3. Korean textbooks to match local circumstances are needed. There should be a basic writing text written by a local Korean department professor and supervision or modification, supplements from Korean language education researchers in Korea. 4. Enlarged Korean training programs are needed. Furthermore, if Korean and Russian university students are to study in Korea, there should be programs offering a dual degree among other things. 5. Methodical, overall examination of overseas Korean regions like Sakhalin is necessary. Also in the case of far east Russia, connectivity between Vladivostok, Khabarovsk and Sakhalin needs to be strengthened.

A Study on the Architectural Status and Improvement of Korean Used Car Trade Facility - based on Benchmarking of Japanese Used Car Trade Facilities - (한국 중고차 거래소 건축 현황과 개선방안 연구 - 일본 중고차 거래소의 벤치마킹을 중심으로 -)

  • Song, Kyuman
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.35 no.6
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    • pp.47-58
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    • 2019
  • According to the Korea Ministry of Transportation report in 2015, domestic used car trade (3.66million) is twice the number of new car sales (1.84million). However, contrary to the quantitative growth of the used car trading volume, chaotic used-car market practice has not been improved and also, space that holds these markets (facilities) has remained at a very low level of quality. Lemon Market, asymmetry of information, false bait, tout, dual contracts, negative words that qualify the used car market information are still in place. The aim of this study was to understand the unique circumstances of the used car sales market distinguished from new cars, and to analyse the problems of recent domestic used car market facilities and afterwards to draw guidelines for new used car facility architecture. Through literature review, surveys, the characteristics of domestic used car market have been organised and field research and competitive analysis of the Korea used car market architecture is followed. As a result, empirical guideline for Korea used-car market facility is introduced.