• 설비공학논문집
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• 제13권7호
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• pp.595-601
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• 2001

We applied PIV method to obtain instantaneous and ensemble averaged velocity fields from the first row to the fifth row of a staggered tube bundle. The Reynolds number based on the tube diameter and the maximum velocity was set to be 4,000. Remarkably different natures are observed in the developing bundle flow. Such differences are depicted in the mean recirculating bubble length and the vorticity distributions. The jet-like flow seems to be a dominant feature after the second row and usually skew. However, the ensemble averaged fields show symmetric profiles and the flow characteristics between the third and fourth measuring planes are not so different. comparison between the PIV data and the RANS simulation yields severe disagreement in spite of the same Reynolds number. It can be explained that the distinct jet-like unsteady motions are not to be accounted in th steady numerical analysis.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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• pp.405-424
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• 2001

Many simulation models have been built to facilitate simulation technique in designing, evaluating, and optimizing supply chains. Simulation is preferred to deal with stochastic natures existing in the supply chain. Moreover simulation has a capability to find local optimum value within each component through entire supply chain. Most of supply chain simulation models have been developed on the basis of discrete-event simulation. Since supply chain systems are neither completely discrete nor continuous, the need of constructing a model with aspects of both discrete-event and continuous simulation is provoked, resulting in a combined discrete-continuous simulation. In this paper, an architecture of combined modeling for supply chain simulation is proposed, which includes the equation of continuous portion in supply chain and how these equations are used in the supply chain simulation models. A simple example of supply chain model dealing with the strategic level of supply chain presented in this paper shows the possibility and the prospect of this approach.

• Journal of Korean Neurosurgical Society
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• 제49권2호
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• pp.116-119
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• 2011

The surgical as well as endovascular treatment of blood-blister-like aneursysms (BBAs) is extremely difficult because of these pathological natures, such as small and the fragile necks. The optimal treatment of BBAs has remained uncertain. Stents are known to divert blood flow and induce thrombosis of intracranial aneurysms. We report 3 cases of successful obliteration of BBAs after multiple stents placement.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.427-430
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• 2005

The purpose of this study is to choose the right chemical admixture to reduce slump loss of lightweight aggregate concrete. So we compare 3 types of chemical admixture as measuring slump loss from mixing to 60 minutes. The lightweight aggregate of this study is made by clayt and dust from lots of industry. To save natures, we will use many types of industrial wastes and try to spend much making artificial aggregate.

• Journal of Acupuncture Research
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• 제24권1호
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• pp.217-225
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• 2007

Objectives: This sutdy aims to research the trend of the studies related with acupuncture treatment of asthma. Methods: We searched the electronic database and reviewed ReT studies comparing the effect of sham and real acupuncture published after 2000 Results: We selected eight articles. Effectiveness of asthma acupuncture treatment was generally insufficient. Three articles reported acupuncture to be effective in subjective symptoms and quality of life. Other three articles reported that acupucture treatment was moderately effective but, insignificant compared to sham acupuncture treatment. Some articles reported that acupucture treatment was significant in the decrease of drug dosage and immunologic regulation. Conclusion : For the study on acupuncture treatments in asthma, it is necessary that we conduct research on the various natures of acupuncture. More clinical data would be needed to prove the effects of acupuncture treatment in asthma.

• 천문학회지
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• 제29권spc1호
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• pp.303-305
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• 1996

The evolution of solar magnetic arcades is investigated with the use of MHD simulations imposing resistivity on sheared magnetic fields. It is found that there is a critical amount of shear, over which magnetic reconnection can take place ill an arcade-like field geometry to create a magnetic island. The process leading to reconnect ion cannot. be solely attributed to a tearing instability, but rather to a reactive evolution of the magnetic arcade under resistivity. The natures of the arcade reconnection are governed by the spatial pattern of resistivity. A fast reconnection with a small shock angle can only be achieved when the diffusion region is localized. In this case. a highly collimated reconnect ion outflow can tear the plasmoid into a pair, and most of principal features in solar eruptive processes are reproduced.

• 복식
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• 제25권
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• pp.215-231
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• 1995

Semiotics is an external expression for show-ing internal meaning, and the signs express the internal meaning. The architects and the designers are very similar each other in using semiotics for expressing their desires. Histori-cally, the design similarity exists between the architecture and the fashion. In this study, the fashion designs are interpreted by using semiotics of architectural design, especially emphasizing external expression methods for representing internal desires. To express the human body's character-istics, the volume, weight support, structural simplicity, controllability and beauty of fashion were used for the fashion designs, and those characters could be found at the architec-tural patterns. Balenciaga's fashion emphasized the volume, the weigh support, the structural simplicity and the controllability, while Roberto Capucci rejected the approach of using women's body curves, but used the volume and simplicity of natures in addition to Balenciaga's heavy weight design patterns. The control and the modern dedication were used to make the simple patterns by Courreges, and then brought the Modernism to the fashion. Courreges used the cutting characters to func-tional design for expressing the structural sim-plicity.

• Toxicological Research
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• 제21권4호
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• pp.319-323
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• 2005

The aim of the present study was to evaluate systemic bioavailability of surfactin and to determine its pharmacokinetic profiles. The stability of surfactin to pH, temperature and protease was evaluated. Surfactin was resistant to high temperature, a wide range of pH and the action of hydrolytic enzymes. The pharmacokinetic natures of surfactin which were shown the short half-life, rapid clearance and poor bioavailability. The results of study should provide preliminary data of surfactin for further dose-finding studies and for the design of application forms. It is also be important to a context of the safety of surfactin.

• 한국과학교육학회지
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• 제16권3호
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• pp.239-248
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• 1996

Many science teaching models have been devised and published for the students' conceptual change by researchers. However, the science teachers have been confused with so many models to be used in teaching science. Since the models are composed of ambiguous statements, it seems to be difficult for the teachers to understand their characteristics and natures. Therefore, the models were difficult to be adopted in science instructions. In this study, the researcher developed two checklists which were devised especially for the teachers who apply the Cognitive Conflict Process Model (the Procedural Teaching Model using Cognitive Conflict Strategy) in Science Concept Instruction. One is for planning instructions using the model, the other is for examining or analysing them. Each of them consisted of 20 items and 33 items, respectively. Using these checklists, the Cognitive Conflict Process Model can be checked whether it was applied properly in actual instruction or not.

• Progress in Superconductivity
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• 제3권2호
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• pp.168-171
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• 2002

We have demonstrated ramp-edge Josephson junctions using high temperature superconductors without depositing artificial barriers. We fabricated a surface barrier formed naturally during an ion beam etching process and the annealing under the oxygen atmosphere. The experimental results imply that the barrier natures such as the resistivity are varied by the annealing conditions and the ion milling conditions including the beam voltages. Thus, the ann eating and etching conditions should be optimized to obtain excellent junction properties. In optimizing the fabricating factors, the interface-controlled junctions showed resistively shunted junctions like current-voltage characteristics and an excellent uniformity. These junctions exhibited a spread ($1\sigma$) of $I_{c}$ is 10% fur chips containing 7 junctions at 50K.K.