• Title/Summary/Keyword: Stagnation

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Icing Wind Tunnel Tests to Improve the Surface Roughness Model for Icing Simulations (착빙 해석의 표면 거칠기 모델 개선을 위한 착빙 풍동시험 연구)

  • Son, Chankyu;Min, Seungin;Kim, Taeseong;Kim, Sun-Tae;Yee, Kwanjung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.46 no.8
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    • pp.611-620
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    • 2018
  • For the past decades, the analytic model for distributed surface roughness has been developed to improve the accuracy of the icing simulation code. However, it remains limitations to validate the developed model and determine the empirical parameters due to the absence of the quantitative experimental data which were focused on the surface state. To this end, the experimental study conducted to analyze the ice covered surface state from a micro-perspective. Above all, the tendency of the smooth zone width which occurs near the stagnation point has been quantitatively analyzed. It is observed that the smooth zone width is increased as growing the ambient temperature and freestream velocity. Next, the characteristics of the ice covered surface under rime and glaze ice have been analyzed. For rime ice conditions, ice elements are developed as the opaque circular corn in the opposite direction of freestream. The height and interval of each circular corn are increased as rising the ambient temperature. For glaze ice conditions, numerous lumps of translucent ice can be observed. This is because the beads formed by gravity concentrate and froze on the lower surface.

Characteristics of Fluid Force Reduction for Two Different Square Prisms in a Tandem Arrangement (직렬배열에 놓인 크기가 다른 정방형주의 유체력 저감특성)

  • Ro, Ki Deok;Kang, Chang Whan;Park, Kwon Ho
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.41 no.7
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    • pp.435-443
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    • 2017
  • The Characteristics of the flowfields of a square prism having a small square prism were investigated by measuring of lift and drag on the square prism and visualizing the flowfield using PIV. The experimental parameters were the width ratios(H/B=0.2~0.6) of small square prisms to the prism width and the gap ratios (G/B=0~3) between the prism and the small square prism. The drag reduction rate of the square prism initially increased and then decreased with the G/B ratio for the same H/B ratio, and increased with the H/B ratio for the same G/B ratio. The maximum drag reduction rate of 98.0% was observed at H/B=0.6 and G/B=1.0. The lift reduction rate of the square prism was not affected by the width and gap ratios; the total average value was approximately 66.5%. In case of a square prism having a small square prism, the stagnation regions were represented in the upstream and downstream sides of the square prism.

A Case Report of Abdominal Pain with Pseudo-mass of the Gallbladder treated by Oriental Internal Medicine (가성담낭종물(假性膽囊腫物)을 동반한 복통(腹痛)환자 1례(例) 보고(報告))

  • Lim, Hee-Yong;Oh, Jung-Han;Kim, Dong-Woo;Choi, Bin-Hye;Park, Song-Ki;Byun, Joon-Seok;Shim, Yun-Seub;Kim, Guk-Bum;Han, Jong-Hyun;Kim, Sun-Hong;Kim, Eun-Gon;Kim, Sang-Uk;Seong, Ki-Won;Kim, Bong-Suk
    • The Journal of Internal Korean Medicine
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    • v.25 no.2
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    • pp.329-334
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    • 2004
  • There are different kinds of the pseudo-mass of the gallbladder(GB) such as GB stones, GB polyps, GB sludge, and these can be differentiated by simple-ultrasonogram(USG). The most common symptoms of GB polyps are abdominal pain(RUQ), dyspepsia, jaundice, but usually there are no symptoms. GB polyps are commonly treated with a cholecystectomy if 10 mm or more in diameter. Pseudo-mass of the GB is regarded as products of stagnation of the Liver Ki in Oriental Medicine. The patient suffered from mild fever. abdominal pain(RUQ), and jaundice. He was diagnosed with a GB polyp(10 mm), liver cyst(12 mm) by simple USG. We treated him with Acupuncture, Herbal Medicine(Hoinsamgum-tang). After three days of treatment, the symptoms improved, and after one month the GB polyp was removed on the follow up of USG.

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A Prospect and Tasks for Regional Development of Youngnam Area: (1) Development Process and the Quality of Life (영남지역 발전의 전망과 과제: (1) 발전과정과 삶의 질)

  • Choi, Byung-Doo
    • Journal of the Korean association of regional geographers
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    • v.1 no.1
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    • pp.23-43
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    • 1995
  • This paper is the first part of a research which looks into the regional development process and the quality of life of Youngnam area, and which suggests a prospect and tasks for the future development of the region. Youngnam region has grown rapidly on the basis of labor-intensive light industries and standardized Fordist lage-scale heavy industries through the industrialization and urbanization of South Korea from the 1960s; but recently it has shown a relatively downward trend. The recent economic stagnation of Youngnam region can be seen as a result of uneven regional development in the national scale, which has brought out the increasing subcontracting relation within the region, the geographically excessive concentration of firms, the lack of growth potentiality of high-tech industries, the weakness of producer service, and the shortage of financial activities for capital flows. In addition, construction of physical and social infrastructures and management of urban central functions could not meet properly the rapid economic and urban growth of the region. Because of these problematics inherent in the economy of Yougnam region, the occupational status of regional dwellers is more or less unstable, and the wage level of employee as a whole in Youngnam region is lower than those of Seoul, although the wage level of labourers in manufacturing is relatively high. Moreover, the quality of life of dwellers in the region has some difficulties in the use of resources and ecological environment as well as the unequal provision of means of living and welfare facilities, even though it has been improved materially.

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The Purpose and Evaluation of the Korea Broadcasting System's Globalization Project "Insight Asia" (KBS 다큐멘터리의 세계화 프로젝트 '인사이트아시아', 그 의미와 평가)

Study on the Effect of Yipahnsan(立安散) on Angiogenic Inhibition Mechanism (입안산(立安散)이 Angiogenesis 억제기전(抑制棋戰)에 미치는 영향(影響))

  • Lee, Gi-Ryong;Choi, Seung-Hoon;Ahn, Kyoo-Seok
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.4 no.1
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    • pp.177-197
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    • 1998
  • This experimental study was carried out to evaluate the effect of Yipahnsan on angiogenic inhibition mechanism. This study investigates the effects of Yipahnsan on angiogenic inhibition mechanism evaluate cell adhesive inhibition effect, DNA fragmantaion analysis, nuclear condensation assay, FACScan analysis, angiogenic lumen formation assay, immunocytochemistry analysis, RT-PCR for mRNA expression, western blot analysis, confocal analysis for $Ca^{2+}influx$. The results were summarized as follows : 1. The cell adhesive inhibition ability was strongly increased from $5{\mu}g/ml$ on ECV304 cell line and ECVPAR cell line. 2. YY water extract caused $G_0/G_1$ arrest peak to existed on the ECV304 cell line. 3. YY water extract caused inhibition of proliferation and inducement of apoptosis on the collagen coated plate in ECV304 cell line. 4. YY water extract inhibited the lumen formation on the matrigel coated plate in ECV304 cell line. 5. YY water extract inhibited the expressions of LFA-1 and ELAM-1 on ECV304 cell line and ECVPAR cell line. 6. YY water extract inhibited the expressions of MMP-9 and uPA on ECV304 cell line and ECVPAR cell line. 7. YY water extract inhibited the expression of integrin ${\alpha}_v{\beta}_3$ on ECV304 cell line and ECVPAR cell line. 8. YY water extract decreased the change of $Ca^{2+}$ in intracellular on ECV304 cell line and ECVPAR cell line. According to the results, Yipahnsan showed to be a key antagonist of integrin ${\alpha}_v{\beta}_3$, and to be induction of apoptosis by p53 through flow cytometry. This report also demonstrated that expressions of MMP-9 and uPA were blocked under the angiogenesis model. Thus, we suggested that Yipahnsan blocks angiogenesis by inducing apoptosis in ECV304 and ECVPAR cell lines, and another oriental herbal medicine that treats qi-stagnation and blood-stasis type also has angiogenic inhibition effects.

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Consumers' preference about the attributes of 3rd generation device (3세대 디바이스의 속성별 소비자 선호 분석)

  • Jung, Jae-Young;Lee, Joo-Suk;Kwak, Seung-Jun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.3
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    • pp.703-710
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    • 2017
  • Third-generation (3G) devicesare next-generation devices that allow the use of intelligent services and applications through the Internet of Things (IoT). As the market forexisting smart devices like smartphones and tablet PCs enters the stage of stagnation, the world is now focusing on 3G devices, parts, and services. This study is intended to measure the user's benefits from the various attributes of 3G devices by applying an economic valuation method. For this purpose, the conjoint analysis method was applied, which is one of the representative valuation methods. To apply conjoint analysis, the following attributes of 3G devicesare considered: mode of use, power efficiency, life care, and price. By applying the mixed logit model, the marginal willingness-to-pay(WTP) for each attribute was derived. The results are statistically significant. Respondents showed a high preference or complete flexibility in the mode of use attribute. And they were also found to have WTP for improvements in the life care attribute. The implications and quantitative results of this study are expected to be useful for policies and strategies in the 3G device market.

The Progress Report of Weight and Waist Circumference through the Oriental Obesity Treatment (한방비만프로그램을 통한 체중과 부위별 복부둘레의 경과 관찰 및 상관성 연구)

  • Heo, Su-Jeong;Ie, Jae-Eun;Kim, Hyun-Jin;Cho, Hyun-Ju;Myoung, Sung-Min
    • Journal of Korean Medicine for Obesity Research
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    • v.9 no.2
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    • pp.47-56
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    • 2009
  • Objectives The purpose of this study was to investigate the progress of weight and waist circumference(WC) through oriental obesity treatment and clarify the correlation between weight loss and WC change. Methods The subjects were treated from January 2007 to September 2009 in J Oriental Medical Center. Herbal medicine, electroacupuncture, oriental obesity physiotherapy were performed for a month. We checked the change of weight and WC at every treatment. We classified the WC into upper, middle, lower parts specifically and measured them individually. Measurements were analyzed by using one-way repeated measures ANOVA and we also investigated correlation between weight loss and WC change. Results (1) During the first and second treatment sessions, the weight loss was the highest, $0.96{\pm}0.86\;kg$($1.46{\pm}1.32\;%$) and during the 5th and 6th treatment sessions, the lowest $0.37{\pm}0.616\;kg$. The final weight loss was $3.71{\pm}1.476\;kg$($5.51{\pm}2.12\;%$). (2) After 8 treatment sessions, the reductions of upper, middle and lower WC were $3.59{\pm}2.26\;%$, $5.93{\pm}2.75\;%$, $5.51{\pm}3.22\;%$, respectively. As the patients received more treatment, there was a progressive decline in the variation of weight and middle WC. However, the decline rate of upper and middle WC fluctuated during the treatments, forming a W-shaped curve. (3) Analysis of the correlation between the weight loss and WC change shows that the reduction of middle WC was most closely associated with the weight loss. Conclusions This study indicated that the rate of weight loss and WC reduction showed stagnation during the 5th and 6th treatment sessions, and the reduction of middle WC was most closely associated with the weight loss. Since the progress of weight and WC change is an important field of research on obesity, further systemic studies would be needed for the foundation of a clinical guideline.

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Colonial Tourism and Modernism in Korean Modern Architecture - Focused on Railroad Station during Japanese Ruling Era - (한국근대건축에서 식민지관광주의와 모더니즘에 관한 연구 - 일제강점기 철도역사 건축을 중심으로 -)

  • Ahn, Chang-Mo
    • Journal of architectural history
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    • v.11 no.2 s.30
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    • pp.7-22
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    • 2002
  • Architectural style is said to be product reflecting political, social and cultural condition. Especially, in colony, architectural style is strongly related to political condition or policy. After colonization in 1910, public buildings with western historical architectural style in Japanese version were widely built by Japanese colonial government in Korea. And in the late 1920s, modernism style in architecture became dominant in Korea as like other countries. In this situation, curious buildings in strange architectural styles came out. One example is railroad station buildings with traditional Korean architectural style and timber house station having a steep roof which is widely used in North Europe such as Alps area with good sights and mountains. Generally, the colonizer says that colonization is the only way to save the colony at crisis defined by colonizer and they insist that they can help the colony modernize. To justify colonization, the colonizer attributes the colonization to the characteristics of the nation and stagnation of the traditional culture etc.. Accordingly, the colonizer tries to depreciate colony's traditional value and culture. In case of colony which has similar cultural background historically (in this case, economical exploitation is less important than other Asian colony by European power), this depreciation of traditional value and culture in Korea was done more strongly than others. At this time, we should understand special relation between Korea and Japan historically. Even though, colony's locality is adopted by the colonizer in public fields, which is based on political purpose or exotic taste etc.. In early days of Japanese ruling period, Japan never use the Korean traditional facts in public. Therefore there is no use of Korean traditional architectural style in public field. In late 1920s, some railroad station buildings were constructed in new styles without precedence in modern Korea. One is railroad station buildings in Korean traditional architectural style, the other is railroad station buildings in timber house stations having a steep roof which is different form western historical architectural style. It was mystery that Japan had constructed railroad stations in Korean traditional style which Japan had tried to destroy together with Western style railroad station buildings. This paper is made to solve the mystery why the colonizer(Japan) constructed entirely different types of railroad stations at the same time in the late 1920s and 1930s. The key point to solve this mystery is tourism. In this paper, to solve this mystery, I try to use terminology' 'Colonial Tourism' in architecture why colonial power had constructed railroad stations with colony's traditional architectural style and Western style having a steep roof which can be seen north European region.

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A Study on the Application of Zero Rate of V.A.T. to National Housing Supply and Construction Service (국민주택 공급 및 건설용역에 대한 부가가치세 영세율 적용에 관한 연구)

  • Noh, Kye-Won;Hwang, Uk-Sun;Lee, Jong-Gwang;Kim, Yong-Su
    • Korean Journal of Construction Engineering and Management
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    • v.11 no.2
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    • pp.64-73
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    • 2010
  • The stagnation of unsold houses is recently aggravated due to domestic and overseas crisis of finance and real-sector economy and domestic housing construction is in serious difficulty. Thus, tax support is necessary for national housing construction. Due to the current tax exemption system of national housing, V.A.T. paid in the construction of national housing is not deducted. Namely, it is ascribed to consumer as it is reflected in the construction cost. This research intends to analyze the limit of V.A.T. tax exemption system, to present the necessity of applying zero rate and to calculate the scale of non-deduction of V.A.T. purchase tax amount for national housing by analyzing the construction site of apartment house of house constructor in order to analyze the effect of zero rate when it is applied on the basis of above ground. In the zero rate system, V.A.T. is not collected from the consumers like the present tax exemption system. However, the purchase tax amount borne in the construction of national housing is deducted totally. As purchase tax is deducted, constructor will promote supplying national housing thanks to the effect of solving financial difficulties and improving liquidity. Since the architecture cost and parceling-out price can be lowered due to the improved liquidity of constructor, the policy will actually help the people without house.