• 대한기계학회논문집B
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• 제28권1호
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• pp.81-88
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• 2004

In this study, heat and mass transfer characteristics of five components solution (LiBr＋Lil＋LiNO$_3$＋LiCl＋$H_2O$) which could be substituted for commonly used LiBr solution are tested using a helical absorber. The arrangement of helical-typed heat exchangers allows to make the system more compact as compared to conventional one. The effects of experimental parameters, such as the solution flow rate, cooling water, solution temperature, solution concentration and surfactant have been investigated in view of the heat and mass transfer. The results of the experiment of heat and mass transfer performance show that five components solution should have 2％ higher concentration fur equal absorption capacity of LiBr solution. But considering that five components solution have higher solubility than LiBr solution about 4％ high concentration, five components solution could be applied to a small sized water cooled or air cooled absorption chiller/heater. The increase of heat and mass transfer coefficient by surfactant addition is about 25∼30％ and 23∼40％ respectively.

• Archives of Pharmacal Research
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• 제2권1호
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• pp.25-33
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• 1979

In order to find out nutritional effects of Korean edible mushrooms on the multiplication of tissue cells, the alcohol extracts and acid bydrolysates of eleven species of mushrooms were added to Earle's ESS. A comparison of the respective multiplications of HeLa cells in this solution and in control solution of TC=199. Yielded the following result: The alcohol extracts and acid hydrolysates of a Coprinus comatur, Agaricus campestris, Agaricus bisporus, Lentinus edodes, Tricholoma matsutake, Pleurotus ostretus, Ramaria botrytis and Pholiota nameko influenced favorably the maintenance of the normal form and monolayer of HeLa cells. The growth curves of HeLa cells in the cultures containing, respectively, the alcohol extracts and acid hydrolysates of these eight mushrooms showed that five species, i.e., Coprinus comatus, Agaricus compestris, Agaricus bisporus, Lentinus edodes and Tricholoma matsutake effected an excellent multiplication and that the other three species were less effective than those five species. As to the effects on the cell multiplication, no marked difference was observed between the alcohol extracts and the acid hydrolysates of the mushrooms tested.

• ETRI Journal
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• 제31권6호
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• pp.647-652
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• 2009

Solution-processable organic semiconductors have been investigated not only for flexible and large-area electronics but also in the field of biotechnology. In this paper, we report the design and fabrication of biosensors based on completely organic thin-film transistors (OTFTs). The active material of the OTFTs is poly(9,9-dioctylfluorene-co-bithiophene) (F8T2) polymer functionalized with biotin hydrazide. The relationship between the chemoresistive change and the binding of avidin-biotin moieties in the polymer is observed in the output and on/off characteristics of the OTFTs. The exposure of the OTFTs to avidin causes a lowering of ID at $V_D$ = -40 V and $V_G$ = -40 V of nearly five orders of magnitude.

• 한국균학회지
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• 제9권1호
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• pp.25-29
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• 1981

To investigate antitumor components of Korean higher fungi, the carpophores of Schizophyllum commune and Auricularia auricula-judae collected in Kyeong Buk Province were extracted with hot water or 0.1N-NaOH solution. The concentrated extracts were precipitated by addition of ethanol, and the precipitates were purified by dialyzing through visking tube and polysaccharide fractions were obtained. They were found to show antitumor activity against sarcoma 180 implanted in mice. Especially, the inhibition ratio of the extract of Auricularia adicula-judae was 90.8% in the doses of 100mg/kg/day for the period of ten days. The tumor in five of the eight mice was completely regressed. The components of these aqueous extracts were found to be polysaccharide and protein. The hydrolysis of the respective polysaccharide yielded four monosaccharides. After hydrolysis of the protein fraction, 15 amino acids were identified in the respective fraction of S. commune and A. auricula-judae.

• 한국균학회지
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• 제8권2호
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• pp.107-113
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• 1980

To investigate antitumor components of Korean higher fungi, the carpophores of Ganoderma lucidum (Fr.)Karst. were collected at Gal-mae-ri in Gyeong-gi Province and extracted with 0.1N sodium hydroxide solution. The extract was purified by dialyzing through Visking tube and a dark brownish power was obtained. The antitumor activity of the fraction was tested against sarcoma 180 implanted in mice. The tumor inhibition ratio of the fraction against the tumor was 87.6% in doses of 50 mg/kg/day for the period of ten days. The tumor in five of 15 mice was completely regressed. The antitumor fraction was chemically analyzed and found to be a complex of polysaccharide and protein, from which four monosaccharides and eighteen amino acids were identified.

• The Journal of Asian Finance, Economics and Business
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• 제8권4호
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• pp.455-463
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• 2021

The purpose of this study is to identify the relationship between firm's green marketing approach and firm's reputation improvement among customers. To investigate the object of the current study and provides adequate material to fill a gap in the literature, the current author collected abundant textual data from numerous extant literature. Because the author needed to augment about reliability and validity, textual data from trusted peer-reviewed sources was obtained from numerous databases. Based on a large body of literature, this study suggests that companies have to declare their stand based on their positioning to safeguard their reputation as an entity and that of its products and services. The five components of a company adopting a recognized environmental marketing strategy include product strategy, demand strategy, pricing strategy, distribution strategy, and labeling strategy Thus, firms' environmental marketing strategies have to be designed with the complete intent of transformation as a solution to enhance their reputation. The current study concludes that the comparison of environmental marketing strategies does not correctly help in ranking the concern in an effective way, and describe the exact details needed in each of the five categories for a company to carry its operations in a sustainable fashion.

• Steel and Composite Structures
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• 제34권4호
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• pp.511-524
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• 2020

In this research, a simple four-variable trigonometric integral shear deformation model is proposed for the static behavior of advanced functionally graded (AFG) ceramic-metal plates supported by a two-parameter elastic foundation and subjected to a nonlinear hygro-thermo-mechanical load. The elastic properties, including both the thermal expansion and moisture coefficients of the plate, are also supposed to be varied within thickness direction by following a power law distribution in terms of volume fractions of the components of the material. The interest of the current theory is seen in its kinematics that use only four independent unknowns, while first-order plate theory and other higher-order plate theories require at least five unknowns. The "in-plane displacement field" of the proposed theory utilizes cosine functions in terms of thickness coordinates to calculate out-of-plane shear deformations. The vertical displacement includes flexural and shear components. The elastic foundation is introduced in mathematical modeling as a two-parameter Winkler-Pasternak foundation. The virtual displacement principle is applied to obtain the basic equations and a Navier solution technique is used to determine an analytical solution. The numerical results predicted by the proposed formulation are compared with results already published in the literature to demonstrate the accuracy and efficiency of the proposed theory. The influences of "moisture concentration", temperature, stiffness of foundation, shear deformation, geometric ratios and volume fraction variation on the mechanical behavior of AFG plates are examined and discussed in detail.

• 한국시뮬레이션학회논문지
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• 제3권2호
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• pp.57-67
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• 1994

For many practical and industrial optimization problems where some or all of the system components are stochastic, the objective functions cannot be represented analytically. Therefore, modeling by computer simulation is one of the most effective means of studying such complex systems. In this paper, with discussion of simulation optimization techniques, a case study in machining process for application of simulation optimization is presented. Most of optimization techniques can be classified as single-or multiple-response techniques. The optimization of single-response category, these strategies are gradient based search methods, stochastic approximate method, response surface method, and heuristic search methods. In the multiple-response category, there are basically five distinct strategies for treating the responses and finding the optimum solution. These strategies are graphical method, direct search method, constrained optimization, unconstrained optimization, and goal programming methods. The choice of the procedure to employ in simulation optimization depends on the analyst and the problem to be solved.

• Journal of Electrical Engineering and Technology
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• 제8권2호
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• pp.316-325
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• 2013

Multilevel inverters produce a staircase output voltage from DC voltage sources. Requiring great number of semiconductor switches is main disadvantage of multilevel inverters. The multilevel inverters can be divided in two groups: symmetric and asymmetric converters. The asymmetric multilevel inverters provide a large number of output steps without increasing the number of DC voltage sources and components. In this paper, a novel topology for multilevel converters is proposed using cascaded sub-multilevel Cells. This sub-multilevel converters can produce five levels of voltage. Four algorithms for determining the DC voltage sources magnitudes have been presented. Finally, in order to verify the theoretical issues, simulation is presented.

• 한국컴퓨터그래픽스학회논문지
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• 제20권2호
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• pp.25-32
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• 2014

본 논문은 물리 시뮬레이션 환경에서 일련의 강체요소가 인과사슬에 따라 연쇄적으로 구동되는 가상의 루브 골드버그 기계를 합성하기 위한 예제 기반 접근방법을 제안한다. 일련의 요소 집합이 주어졌을 때, 본 논문의 목표는 사용자가 명시한 이동의 시작 및 종료위치, 그리고 경계 영역 조건을 만족하는 범위에서 이들 요소로만 구성된 루브 골드버그 기계를 자동으로 구축하는 것이다. 이를 위하여, 먼저 적은 개수의 요소로 구성된 소규모 컴포넌트들을 무작위로 추출한 후 모든 컴포넌트 쌍에 대한 결합 가능성을 하나의 그래프 구조로 표현한다. 이 그래프 위에서의 경로 탐색을 통하여 공간 상에 펼쳤을 때 사용자가 지정한 요구 조건을 만족시키는 경로를 찾고, 해당 경로에 따라 순차적으로 컴포넌트를 조립함으로써 기계를 구축한다. 완성된 기계가 물리 시뮬레이션 환경에서 정확히 동작함을 보장하기 위하여, 끝으로 간단한 그리디 알고리즘을 적용하여 조립된 컴포넌트들의 위치를 정교하게 조절한다. 다섯 종류의 요소만을 이용하여 만든 다양한 구조의 루브 골드버그 기계를 보임으로써 본 논문에서 제안한 방법의 유용성을 보인다.