• Journal of Photoscience
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• 제1권1호
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• pp.15-23
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• 1994

The absorption and fluorescence spectral properties of piroxicam (PRX) in the hydrogenbonding solvents show the most sensitive dependence on the concentration ranging from 8 x 10$^{_5}$ to 2 x10$^{_5}$ M. These are attributed to both the solvent-mediated ground-state intermolecular proton transfer (GSIerPT) leading to formation of the ground state anion and the excited-state intmmolecular proton transfer (ESIraPT). The concentration dependences of the time-resolved emission kinetics at both room temperature and 77 K have also been investigated. It is shown that in the excited state, the ESIraPT of PRX is the dominant process to form a keto tautomer at the high concentration, whereas at the low concentration the excited-state conformational change of the anion is an additional process leading to formation of a zwitterion. The ESI~PT of PRX in the hydrogenbonding solvent is coupled with the ultrafast excited-state solvent reorganization.

• Journal of Mechanical Science and Technology
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• 제18권6호
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• pp.1042-1051
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• 2004

The vortex flow characteristics of a sharp-edged delta wing at high angles of attack were studied using a computational technique. Three dimensional, compressible Reynolds-averaged Navier-Stokes equations were solved to understand the effects of the angle of yaw, angle of attack, and free stream velocity on the development and interaction of vortices and the relationship between suction pressure distributions and vortex flow characteristics. The present computations gave qualitatively reasonable predictions of vortical flows over a delta wing, compared with past wind tunnel measurements. With an increase in the angle of yaw, the symmetry of the pair of leading edge vortices was broken and the vortex strength was decreased on both windward and leeward sides. An increase in the free stream velocity resulted in stronger leading edge vortices with an outboard movement.

• 한국응용과학기술학회지
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• 제17권2호
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• pp.89-93
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• 2000

The oxidation of methane was carried out in six different configurations of plasma reactors in order to study the radical reactions inside and outside of the plasma zone and to explore the method to control them. Various radicals and reactive molecules, such as CH, $CH_{2}$, $CH_{3}$, H, and O(from $O_{2}$) were generated in the plasma. A variety of products were produced through many competing reaction pathways. Among them. partial oxidation products were usually not favored, because the intermediates leading to the partial oxidation products could be oxidized further to carbon dioxides easily. It is important to control the free radical reactions in the plasma reactor by controlling the experimental conditions so that the reactions leading to the desired products are the major pathways.

• The Korean Journal of Physiology and Pharmacology
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• 제17권1호
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• pp.1-8
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• 2013

Understanding the cellular and molecular mechanisms involved in the development and progression of pulmonary hypertension (PH) remains imperative if we are to successfully improve the quality of life and life span of patients with the disease. A whole plethora of mechanisms are associated with the development and progression of PH. Such complexity makes it difficult to isolate one particular pathway to target clinically. Changes in intracellular free calcium concentration, the most common intracellular second messenger, can have significant impact in defining the pathogenic mechanisms leading to its development and persistence. Signaling pathways leading to the elevation of $[Ca^{2+}]_{cyt}$ contribute to pulmonary vasoconstriction, excessive proliferation of smooth muscle cells and ultimately pulmonary vascular remodeling. This current review serves to summarize the some of the most recent advances in the regulation of calcium during pulmonary hypertension.

• 기술혁신학회지
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• 제1권3호
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• pp.402-418
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• 1998

This study attempts to analysis of the 1'ole and B/C(Benefict/Cost)of National Supported Supercomputing Center in process of the promotion for informatization in Korea. ETRI Supercomputing Center, as National Supported Supercomputing Center, was established in 1967 as a laboratory of KIST(Korea Institute of Science and Technology). ETRI Supercomputer Center have acted a leading role as National HPCC(High Performance Computing and Communication) in Korea. The result of B/C analysis of En Supercomputer Center showed that it is twenty times benefit as many as cost for the last 30 years. As soon as possible, it was Suggested that ETRI Supercomputer Center must be developed as National Supercomputing Center(NSC).

• 한국통신학회논문지
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• 제21권5호
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• pp.1345-1359
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• 1996

This paper presents a floating point arithmetic unit (FPAU) for supescalar microprocessor that executes fifteen operations such as addition, subtraction, data format converting, and compare operation using two pipelined arithmetic paths and new rounding and normalization scheme. By using two pipelined arithmetic paths, each aritchmetic operation can be assigned into appropriate arithmetic path which high speed operation is possible. The proposed normalization an rouding scheme enables the FPAU to execute roundig operation in parallel with normalization and to reduce timing delay of post-normalization. And by predicting leading one position of results using input operands, leading one detection(LOD) operation to normalize results in the conventional arithmetic unit can be eliminated. Because the FPAU can execuate fifteen single-precision or double-precision floating-point arithmetic operations through three-stage pipelined datapath and support IEEE standard 754, it has appropriate structure which can be ingegrated into superscalar microprocessor.

• 제어로봇시스템학회논문지
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• 제9권12호
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• pp.994-1000
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• 2003

A new relative motion control methodology for a following system to an independent leading system is proposed for controlling relative position, velocity, and tension etc. It is based on maintaining minimum relative error between two independent systems. The control command of the following system to a leading system is generated by adding the current command and the output of the relative error compensation. The proposed control method is implemented on the experimental equipment which is a wire winding-unwinding system to control the tension of the line. The results show the unwinding system(follower) following the independent motion of the winding system(leader) to control the constant tension of the line in order to keep the roller dancer in reference position. The relative motion control method proposed in this paper can be applied to high precision equipment for unwinding and winding fine wire, fine fiber, and tape etc.

• 농업과학연구
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• 제43권2호
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• pp.153-162
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• 2016

Chilli is a widely consumed crop throughout the world. However, chilli anthracnose is a major constraint in chilli production leading to huge economic losses worldwide. Colletotrichum is a large genus of Ascomycete fungi, containing species that cause anthracnose diseases on a wide range of crops of economic value. This review is aimed at critically and accurately examining the taxonomic identification of Colletotrichum species by morphological and molecular approaches as well as assessing their management options. The use of appropriate integrated management practices, such as cultural, mechanical, chemical, and biological control, are important in chilli anthracnose disease prevention and control. Emphasis is laid on the use of biological control because it is cost effective and eco-friendly, and is an appropriate approach for disease management. The use of resistant cultivars is the cheapest, easiest, safest, and most effective means of controlling crop diseases. But, since no resistant cultivars of chilli have been developed and commercialized, it is very important to develop biological management strategies. Further studies leading to integrated disease management strategies need to be carried out.

• 한국의류학회지
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• 제27권11호
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• pp.1219-1228
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• 2003

This research was conducted to find out what the general globalization trends of Korean fashion enterprises are, and what the factors required the Korean fashion enterprises to improve the global competitiveness under the globalized circumstances are. The data were collected from the survey by questionnaire on Korean leading fashion enterprises and the Directory of Companies Branching out abroad in 2000/2001(Korea Trade-Investment Promotion Agency, 2000). The Results of the research are as follows: first, Korean fashion enterprises expanded evenly worldwide in the sales and distribution functions while relying heavily on Asian countries for manufacturing functions; Secondly, the globalization of Korean leading fashion enterprises was progressed, but still remains at the stage of the sales of manufacturing capability or the sales of low costs products rather than at the stage of manufacturing products of high added-value or the sales of design or marketing capability. Thirdly, the factors for the global competitiveness of the Korean fashion enterprises are related to capability of low cost, quick response, product development, marketing, internationalization and high value added.

• Journal of Chest Surgery
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• 제22권1호
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• pp.50-58
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• 1989

The emergence and expansion of cardiac surgery over the past decade has resulted in an increasing number of patients undergoing cardiac operations but many kinds of heart surgery was realized only palliative, resulting in increasing numbers of secondary cardiac procedures. From 1978 to 1988, 10 cases of various congenital heart diseases and 17 cases of acquired heart diseases were reoperated at Hanyang University Hospital. The leading indication of second operation was residual shunt or valvular malfunction due to technical failure in congenital heart disease and primary valve failure, endocarditis, paravalvular leakage were for acquired heart disease. The mortality of reoperation was 0% for congenital heart disease and 11.7%[2 death among the 17 patients] for acquired heart disease. The leading causes of death were myocardial failure, sepsis with endocarditis, acute renal failure and congestive heart failure.