• Title/Summary/Keyword: internal circulation

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Investigation on Freezing in the Freezing Compartment of a Side by Side Refrigerator (양문형 냉장고 냉동실 결빙원인해석 및 최소화 방안)

  • Kim, Y.K.;Jung, H.Y.;Choi, Y.H.;Lee, Y.W.
    • Journal of Power System Engineering
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    • v.14 no.1
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    • pp.34-39
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    • 2010
  • A side by side refrigerator is popularly used one among electric home appliances according to the rise of the customer's living standard. But the frost problem in freezing compartment comes out whenever we develop the high quality refrigerator. In this research, internal flow simulation and temperature measurement were carried out by using CFD and T-type thermocouple respectively in order to understand freezing mechanism. It was revealed that the amount of frost beneath the 1st and 2nd shelves is approximately 40% of total frost and the cause of frost generation is due to bad circulation of low speed cold flow. Using this analysis, the shapes of outlets under shelves are modified. So, the amount of frost in this modified model decreases 6% comparing to original one.

Pharmacognostical Studies on the Angelica species from Korea (한국산 Angelica속 식물의 생약학적 연구)

  • Ahn, Mi-Jeong;Bae, Ji-Yeong;Park, Jong-Hee
    • Korean Journal of Pharmacognosy
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    • v.42 no.2
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    • pp.103-106
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    • 2011
  • Angelica species from Korea has been used mainly as to promoting blood circulation, relieving pain and headache in common cold in Korea. To clarify the botanical origin of Angelica species from Korea, the anatomical characteristics of Angelica gigas, Angelica koreanum and Angelica purpuraefolia were studied. As a result, it was found the fact that the internal morphological patterns for the three Angelica species could discriminate from them by the secretory canal, xylem fiber and vascular bundle. According to these three criteria, Angelica species from Korea could be clearly distinguished so that the toxication by Angelica purpuraefolia can be prevented.

Anti-Alzheimer′s drug, taurine transport through the blood-brain barrier in mice and pharmacokinetics

  • Kim, You-Jung;Kang, Young-Sook
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1998.11a
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    • pp.193-194
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    • 1998
  • Recently, evaluation of brain transport of taurine which is possible to effect on Alzheimer's disease has investigated in rats. Also, internal carotid artery perfusion (ICAP) method is very useful for measuring of blood-brain barrier (BBB) permeability in rats. But ICAP has difficulties to evaluate of BBB permeability in mice especially. In the present study examines neuropharmaceutials permeability through the BBB in mice by common carotid artery perfusion (CCAP) method that modify ICAP method and require simple surgery. The external carotid artery (ECA) is cannulated with coagulating pterygopalatine artery (PPA) on ICAP method, while CCA is cannulated without coagulating PPA on CCAP method. The CCAP method require 4-5 fold higher infusion rate than ICAP method because an additional factor of 2 must be incorporated to adjust for fluid loss to the extracerebral circulation.

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Research on Vertical Space System of Mixed-Use Complex

  • Wang, Zhendong;Wang, Yinpu
    • International Journal of High-Rise Buildings
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    • v.4 no.2
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    • pp.153-160
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    • 2015
  • As the predominant mode of vertical urban development in China, mixed-use complexes provide the optimal case for the research of sustainable and vertical urbanism. This paper reviews three typical mixed-use complexes with various vertical space systems in Shanghai via the combination of field observation, questionnaires and software analysis. It then proceeds to determine which vertical space system is most effective for encouraging sustainable vertical urban development from the perspective of spatial efficiency. Finally, it concludes with an evaluation of the relative capabilities of the design features of a mixed-use complex: to create external dimensional-connections, to create multiple internal connections, and to organize overall composite functions.

A Simulation Study for Optimizing the Functionality of an Automated Storage and Retrieval System (자동창고 시스템의 최적안 도출을 위한 모의실험적 연구)

  • Kim, Moon Ki
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.23 no.5
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    • pp.505-511
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    • 2014
  • The functional role of warehouses in modern industry is changing from an established concept of storage to a concept of circulation. The target of this study is to improve the stacker crane's efficiency for the internal operations of the Automated Storage and Retrieval System (AS/RS). Eight operating schemes are proposed under the combination of three conditions, namely, the storing method, the layout type, and the sequence of command execution. The moving distance of the stacker crane is calculated using the same gateway data through a simulation based on a C# program. The optimal operating scheme is proposed based on the analyzed simulation results. In conclusion, the combination of conditions of random storage, two-way type warehouse, and dual command execution elicits optimum results in travel efficiency for the stacker crane.

블라인드 장착에 따른 실내 공기 순환 연구

  • Nam, Do-U;Hwang, Jae-Min
    • Proceeding of EDISON Challenge
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    • 2016.03a
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    • pp.625-627
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    • 2016
  • 본 논문은 EDISON CFD의 전처리기, eMEGA를 이용하여 격자를 생성하고, 2차원 정렬 격자 기반 비압축성 해석자를 이용하여 유동해석을 진행한 뒤 후처리기, eDAVA를 통해 유동선을 그려 블라인드 장착에 따른 실내 공기 순환에 대한 연구 내용을 담고 있다. 본 연구는 시중에 판매중인 사생활 보호용 블라인드를 포함, 여러 블라인드의 장착 여부에 따라 실내 내부 공기 순환의 양상을 확인하고 실제로 블라인드 장착 시 실내환기에 어떤 영향을 주는지 유동 선을 통해 확인해 보았다. 블라인드 미장착시, 실내 전체적으로 공기가 고루 순환되는 모습을 보였으며, 블라인드 장착 시 대체로 블라인드 형태에 따라 유동이 이동하는 것을 볼 수 있었다. 본 연구는 사생활 보호와 환기 효율성의 관점에서의 소비자 선택권에 영향을 미치는 효과를 가져 올 것으로 보인다.

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A Case of Progressive Pigmented Purpuric Dermatosis (진행성 색소성 자반병 한방 치험 1례)

  • Choi, In-Hwa
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.14 no.2
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    • pp.194-197
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    • 2001
  • Progressive pigmented purpuric dermatosis(Schamberg's disease, purpura simplex) is an uncommon eruption characterized by petechiae and patches of brownish pigmentation, particularly on the lower extremities. Lesions remain for months or years and present only a cosmetic problem. there is no hematologic disease, venous insufficiency, or associated internal disease. The most characteristic feature is orange brown, pinhead-sized "cayenne pepper" spots. It is hard to find similar disease in Oriental Medicine, however it could be though related with 瘀血. We observed and treated a 25 old female with progressive pigmented purpuric dermatosis on her lower extremities, without pain and itching sign. About 1 year after our treatment, herb-medication. acupuncture treatment, negative therapy and applied aroma oil in order to remove the 瘀血(a kind of congestion) & inner heat and promote the circulation of her blood, the area of pigmented purpuric dermatosis was decreased remarkably and the colour was lighter. She is been treated continuously now and satisfied with the efficacy of treatment.

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The Effectiveness of the Municipal Libraries in Seoul (서울특별시립도서관의 유효성에 관한 연구)

  • Kim Hyang-shin
    • Journal of the Korean Society for Library and Information Science
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    • v.16
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    • pp.243-279
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    • 1989
  • Public library effectiveness is determined by a complexity of the internal and external environments of the library. The purpose of this article is to investigate community environments and library resources as determinants of the output measures of the 15 municipal libraries in Seoul and to cope with changes in the environments for the improvement of their performance. This study is based on the hypotheses that the library's output would be proportioned to the size of budget and library collection, and to the relationships between the characteristics of the library and of the community in which the library develops. The variables identified in this .study are population density, family size, institutions (social, cultural, financial and educational), presence of the mass media, size of service area, and economic level of the community. The output measures employed for analysis are: number of professional staff, expenditures, number of books in the collection, number of books added annually, total circulation, number of library visits, circullation per capita, library visits per capita, .and registration as a percentage of population. The recommendation made in this study is the innovation of the 15 libraries in organization.

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Functional Implications of HMG-CoA Reductase Inhibition on Glucose Metabolism

  • Han, Ki Hoon
    • Korean Circulation Journal
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    • v.48 no.11
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    • pp.951-963
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    • 2018
  • HMG-CoA reductase inhibitors, i.e. statins, are effective in reducing cardiovascular disease events but also in cardiac-related and overall mortality. Statins are in general well-tolerated, but currently the concerns are raised if statins may increase the risk of new-onset diabetes mellitus (NOD). In this review, the possible effects of statins on organs/tissues being involved in glucose metabolism, i.e. liver, pancreas, adipose tissue, and muscles, had been discussed. The net outcome seems to be inconsistent and often contradictory, which may be largely affected by in vitro experimental settings or/and in vivo animal conditions. The majority of studies point out statin-induced changes of regulations of isoprenoid metabolites and cellassociated cholesterol contents as predisposing factors related to the statin-induced NOD. On the other hand, it should be considered that dysfunctions of isoprenoid pathway and mitochondrial ATP production and the cholesterol homeostasis are already developed under (pre)diabetic and hypercholesterolemic conditions. In order to connect the basic findings with the clinical manifestation more clearly, further research efforts are needed.

Thermal-hydraulic behavior simulations of the reactor cavity cooling system (RCCS) experimental facility using Flownex

  • Marcos S. Sena;Yassin A. Hassan
    • Nuclear Engineering and Technology
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    • v.55 no.9
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    • pp.3320-3325
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    • 2023
  • The scaled water-cooled Reactor Cavity Cooling System (RCCS) experimental facility reproduces a passive safety feature to be implemented in Generation IV nuclear reactors. It keeps the reactor cavity and other internal structures in operational conditions by removing heat leakage from the reactor pressure vessel. The present work uses Flownex one-dimensional thermal-fluid code to model the facility and predict the experimental thermal-hydraulic behavior. Two representative steady-state cases defined by the bulk volumetric flow rate are simulated (Re = 2,409 and Re = 11,524). Results of the cavity outlet temperature, risers' temperature profile, and volumetric flow split in the cooling panel are also compared with the experimental data and RELAP system code simulations. The comparisons are in reasonable agreement with the previous studies, demonstrating the ability of Flownex to simulate the RCCS behavior. It is found that the low Re case of 2,409, temperature and flow split are evenly distributed across the risers. On the contrary, there's an asymmetry trend in both temperature and flow split distributions for the high Re case of 11,524.