• Journal of applied mathematics & informatics
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• 제26권1_2호
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• pp.355-364
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• 2008

Under pathological stress stimuli, dynamics of a biological system can be changed by alteration of several components such as functional proteins, ultimately leading to disease state. These dynamics in disease state can be modeled using differential equations in which kinetic or system parameters can be obtained from experimental data. One of the most effective ways to restore a particular disease state of biology system (i.e., cell, organ and organism) into the normal state makes optimization of the altered components usually represented by system parameters in the differential equations. There has been no such approach as far as we know. Here we show this approach with a cardiac hypertrophy model in which we obtain the existence of the optimal parameters and construct an optimal system which can be used to find the optimal parameters.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.82-87
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• 1994

Signal transduction through G protein-coupled receptors comprises three functional components, a receptor, a G protcin and a effector protein. Work over the last sevcral ycars has led to the characterization or virtually all of the components or these systems. what has come out or those studies is that these mechanisms of signal transduction are pervasive in nature being found in mammalian and avian species, as well as lower organisms such as yeast and slime mold. It is known that G protein-coupled receptors mediate the action of such diverse molecules such as small hormones and neurotransmitters, small peptide molecules as well as glycoprotein hormones and various sensory perceptions such as light, olfaction and most likely taste.

• Journal of Mechanical Science and Technology
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• 제18권4호
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• pp.573-581
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• 2004

A self-contained wall climbing robot, called MRWALLSPECT (Multi-functional Robot for WALL inSPECTion) II, is developed. It is designed for scanning external surfaces of gas or oil tanks with small curvature in order to find defects. The robot contains all the components for navigation in itself without any external tether cable. Although it takes the basic structure of the sliding body mechanism, the robot has its original characteristic features in the kinematic design with closed link mechanism, which is enabled by adopting a simple and robust gait pattern mimicking a biological system. By employing the proposed link mechanism, the number of actuators is reduced and high force-to-weight ratio is achieved. This paper describes its mechanism design and the overall features including hardware and software components. Also, the preliminary results of experiments are given for evaluating its performances.

• 한국인쇄학회지
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• 제15권2호
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• pp.25-40
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• 1997

This research was carried out to investigated the effect of base paper and latex binder on printability and obtical properties of coated paper. Especially, it examined the effect of th pH of vase paper surface and functional groups of latices on the interactions between coating color components and on the structure of coated layer. It was found that the behavior of coating color containing amphoeric latex depends on the pH in the boundary region between coating color and base paper. Thus, the coating color formulated with amphoteric latex formed bulky coating layer by inducing stronger interaction between paper surface and coating components than the coating color with anionic latex. The coated paper with amphoteric latex showed better optical properties (i.e.gloss and optical) and printability (i.e. ink receptivity, wet ink receptivity, and ink set off) than the conventional anionic latex in the acidic and alkaline paper. However, dry pick strength of the coated paper was less decreased. This result indicated that amphoteric latex could also be applied practically to the alkaline paper.

• 대한핵의학회지
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• 제36권1호
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• pp.80-86
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• 2002

Presently, PET is widely used in oncology, but suffers from limitations of poor anatomical information. To compensate for this weakness, a combined PET/CT has been developed by Professor Townsend at the University of Pittsburgh Medical Center. The prototype was designed as PET and CT components combined serially in a gantry. The CT images provide not only accurate anatomical location of the lesions but also transmission map for attenuation correction. More than 300 cancer patients have been studied with the prototype of PET/CT since July, 1998. The PET/CT studies affected the managements in about $20{\sim}30%$ of cancer patients. These changes are a consequence of the more accurate localization of functional abnormalities, and the distinction of pathological from normal physiological uptake. Now a variety of combined PET/CT scanners with high-end PET and high-end CT components are commercially available. With the high speed of multi-slice helical CT, throughput of patient's increases compared to conventional PET. Although some problems (such as a discrepancy in breathing state between the two modalities) still remain, the role of PET/CT in oncology is very promising.

• Preventive Nutrition and Food Science
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• 제22권2호
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• pp.67-80
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• 2017

Cholesterol is a vital component of the human body. It stabilizes cell membranes and is the precursor of bile acids, vitamin D and steroid hormones. However, cholesterol accumulation in the bloodstream (hypercholesterolemia) can cause atherosclerotic plaques within artery walls, leading to heart attacks and strokes. The efficiency of cholesterol absorption in the small intestine is of great interest because human and animal studies have linked cholesterol absorption with plasma concentration of total and low density lipoprotein cholesterol. Cholesterol absorption is highly regulated and influenced by particular compounds in the food supply. Therefore, it is desirable to learn more about natural food components that inhibit cholesterol absorption so that food ingredients and dietary supplements can be developed for consumers who wish to manage their plasma cholesterol levels by non-pharmacological means. Food components thus far identified as inhibitors of cholesterol absorption include phytosterols, soluble fibers, phospholipids, and stearic acid.

• Preventive Nutrition and Food Science
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• 제7권2호
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• pp.119-122
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• 2002

Oryza sativa cv. Mihyangbyo is one of several recently developed varieties of rice; characterized by high levels of aromatic components, which may increase its sensory and nutritional properties. In conjunction with our continuing investigation of bioactive components of improved grain varieties, a quinolone alkaloid was isolated from the n-butanol soluble fraction of the aleurone layer of Oryza sativa cv. Mihyangbyo (Gramineae) through activity-guided fractionation and isolation. The compound exhibited moderate antineoplastic activity in a human leukemia cell line (U937) with an $IC_{50}$/ value of 118.1 ug/mL, based on the MTT(3-[4, 5]dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide) cell proliferation assay. The chemical structure of the functional compound was determined, based on physical and spectroscopic characteristics.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2004년도 품질경영모델을 통한 가치 창출
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• pp.261-265
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• 2004

As a car is a combination of a lot of components, it is necessary to consider safety and durability. Even there are lots of components for a car, the connector is one of the most important one since it connects functional electric signal. Usually automotive connector is tested under each car maker's test specification, which should have dependability characteristic. In this paper, we aim to review the current test specifications in view of dependability, and propose an accelerated life test for the automotive connector.

• Molecules and Cells
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• 제25권4호
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• pp.553-558
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• 2008

Essential aspects of the innate immune response to microbial infection appear to be conserved between insects and mammals. In order to identify new Drosophila melanogaster genes involved in the immune response, we performed gene expression profiling of Drosophila SL2 cells stimulated with bacterial (LPS/PGN) or fungal (curdlan) components using a cDNA microarray that contained 5,405 Drosophila cDNAs. We found that some genes were similarly regulated by LPS/PGN and curdlan. However, a large number, belonging to the functional classes of cell organization, development, signal transduction, morphogenesis, cell cycle, and DNA replication, displayed significant differences in their transcription profiles between the two treatments, demonstrating that bacterial and fungal components induce different immune response even in an in vitro cell system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
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• pp.242-244
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• 2003

The functional test of protection relays is divided into two kind of test types; the steady-state test and dynamic test. Because the steady-state test is comparatively easy, this test is used to test the characteristics of the relaying elements, operating values, resetting values and etc. using equipment such as Doble. But the dynamic test has to be performed on the test environment with RTDS(real time digital simulator) because of the dynamic characteristics of real protection relays. Therefore, it is not usually easy to perform dynamic test of relays using power system simulation tool based on PC(personal computer) such as PSCAD/EMTDC. This paper discusses how to develop and implement a test model and user-defined components that can be performed dynamic test using PSCAD/EMTDC.