• 한국연초학회지
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• 제20권1호
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• pp.124-130
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• 1998

This study was conducted to evaluate the ability of anion generating air cleaner to remove gases, vapor and particles from closed room contaminated with environmental tobacco smoke (ETS). The measurements covered particle sizes of 13.8-542.5nm, particle concentration, surface area, volumes UVPM, FPM, solanesol, and the following gases and vapor; carbon dioxide, carbon monoxide, nicotine, and 3-ethenylpyridine. Tobacco smoke was generated and mixed in a closed room in which the airflow rates were in the range of 0.00-0.04 m/s. The anion generating air cleaner was startedl and the decay rates for the gases, vapor and particles were measured, When the use of anion generating air cleaner, solid components of ETS, such as respirable suspended particle (RSP), utraviolet particulate matter (UVPM, fluorescent particulate matter (FPM) and solanesol was sharply decreased, and vapor phase components of ETS, such as nicotines 3-ethenylpyidine were modelately decreased by time elapse. Even the use of anion generation air cleaner, the decreasing rate of carbon dioxide concentration was similar with control, and the decreasing rate of carbon monoxide was slower than that of control. Our results indicated that the use of anion generting air cleaner had an effect on reduction of solid and vapor components from ETs, but it had no effect on gaseous components of ETS.

• 대한기계학회논문집A
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• 제25권7호
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• pp.1055-1063
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• 2001

When the interfacial crack of isotropic/orthotropic bi-materials is propagated with constant velocity along the interface, stress and displacement components are derived in this research. The dynamic photoelastic experimental hybrid method for the bimaterial is introduced. It is assured that stress components and dynamic photoelastic hybrid developed in this research are valid. Separating method of stress components is introduced from only dynamic photoelastic fringe patterns. Crack propagating velocity of interfacial crack is 69∼71% of Rayleigh wave velocity of epoxy resin. The near-field stress components of bonded interface of bimaterial are similar with those of pure isotopic material and two dissimilar isotropic bimaterials under static or dynamic loading, but very near-field stress components of bonded interface of bimaterial are different from those.

• Applied Biological Chemistry
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• 제23권2호
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• pp.89-105
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• 1980

Soysauce was made in the salt concentrations of 22.0% and 28.5%, and the changing aspects in nucleotides and their related compounds, free amino acids, free sugars and non-volatile amines which are related to the taste components during the fermentation process with a view to examining the taste components in the ordinary Korean soysauce were studied. And then artificial soysauce was prepared by applying the values derived from the analysis and measurement, and its sensory evaluation was performed. As the result of the sensory evaluation of artificial soysauce prepared according to the value of components analyzed from soysauce which had been fermented for fourty days in the salt concentration of 22.0%, it has been found that artificial soysauce was similar in taste to ordinary Korean soysauce. So, the following facts have been found: glutamic acid and aspartic acid have MSG-like taste, and IMP has a synergistic effect with these acids, which play great roles in ordinary Korean soysauce; both free sugars such as galactose and amino acids such as glycine, alanine and lysine have sweet taste; both amines such as tyramine and histamine, and amino acids such as valine, leucine, isoleucine, and phenylalanine have bitter taste; these components, combined with saline taste of salt and sour taste of organic acids, are assumed to form the unique taste in the ordinary Korean soysauce.

• Korea-Australia Rheology Journal
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• 제13권4호
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• pp.189-196
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• 2001

The phase morphology is an important factor in the rheology of immiscible polymer blends. Through its size and shape, the interface between the two phases determines how the components and the interface itself will contribute to the global stresses. Rheological measurements have been used successfully in the past to probe the morphological changes in model blends, particularly for dilute systems. For more concentrated blends only a limited amount of systematic rheological data is available. Here, viscosities and first normal stress differences are presented for a system with nearly Newtonian components, the whole concentration range is covered. The constituent polymers are PDMS and PIB, their viscosity ratio can be changed by varying the temperature. The data reported here have been obtained at 287 K where the viscosities of the two components are identical. By means of relaxation experiments the measured stresses are decomposed into component and interfacial contributions. The concentration dependence is quite different for the two types of contribution. Except for the component contributions to the shear stresses there is no clear indication of the phase inversion. Plotting either the interfacial shear or normal stresses as a function of composition produces in some cases two maxima. The relaxation times of these stresses display a similar concentration dependence. Although the components have the same viscosity, the stress-component curves are not symmetrical with respect to the 50/50 blend. A slight elasticity of one of the components seems to be the cause of this effect. The data for the more concentrated blends at higher shear rates are associated with a fibrillar morphology.

• 한국과학교육학회지
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• 제38권4호
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• pp.505-518
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• 2018

이 연구에서는 구성주의적 수행평가 워크숍에 참여한 예비 화학교사가 수행평가 과제 개발 과정에서 고려하는 교과교육학 지식(PCK) 구성 요소와 구성 요소 사이 연계의 특징을 분석하였다. 8명의 예비교사가 연구에 참여하였고, 이들은 3주간의 구성주의적 수행평가 워크숍 후 수행평가 과제를 개발하였다. 예비교사의 수행평가 과제 개발 과정을 조사하기 위해 발성 사고법을 사용하였고, 활동을 녹음 및 녹화하였으며 반구조화된 면담을 통하여 자료를 수집하였다. 분석 결과, 개별 수행평가 과제 개발 과정의 구상 단계에서는 과학 평가, 교수 전략, 학생, 내용에 관한 지식이 거의 동일한 비율로 나타났고, 구체화 단계에서는 과학 평가에 관한 지식이 주로 나타났다. 조별 논의 과정에서는 과학 평가, 교수 전략, 학생에 관한 지식의 비율이 거의 같았다. 그러나 과학교육과정에 관한 지식과 하위 요소 중 과학 과정 지식을 고려한 경우는 드물었다. PCK 구성 요소 사이의 연계는 개별 수행평가 과제 개발 과정의 구상 단계에서 과학 교수 전략에 관한 지식을 중심으로 나타났고, 구체화 단계와 조별 논의 과정에서는 학생에 관한 지식을 중심으로 나타났다. 그러나 과학교육과정과 내용에 관한 지식이 다른 PCK 구성 요소와 연계되는 경우는 적었다. 연구 결과를 바탕으로 교육적 시사점에 관하여 논의하였다.

• Food Science and Biotechnology
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• 제17권3호
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• pp.669-674
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• 2008

Zanthoxylum schinifolium and Zanthoxylum piperitum A.P. DC. belong to the Rutaceae family and are perennial, aromatic, and medicinal herbaceous plants. In this study, their aroma compounds were isolated by steam distillation extraction using a Clevenger-type apparatus, and then further analyzed by gas chromatography (GC) and gas chromatograph/mass spectrometry (GC/MS). The yields of the essential oils from Z. schinifolium and Z. piperitum AP. DC. were 2.5 and 2.0%(w/w), respectively, and the color of their oils was quite similar, a pale yellow. From the distilled oil of Z. schinifolium, 60 volatile compounds which make up 87.24% of the total composition were tentatively identified, with monoterpenes predominating. $\beta$-Phellandrene (22.54%), citronellal (16.48%), and geranyl acetate (11.39%) were the predominantly abundant components of Z. schinifolium. In the essential oil of Z. piperitum AP. DC., 60 volatile flavor components constituted 94.78% of the total peak area were tentatively characterized. Limonene (18.04%), geranyl acetate (15.33%), and cryptone (8.52%) were the major volatile flavor compounds of Z. piperitum A.P. DC.

• International Journal of Internet, Broadcasting and Communication
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• 제12권1호
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• pp.111-115
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• 2020

In this paper, I proposed an effective technique for accurately predicting pixel values using edge components. Adjacent pixel values are similar to each other. That is, generally, similarity exists between adjacent pixels in an image. In the proposed algorithm, edge components are detected using the surrounding pixels in the first step, and pixel values are estimated using the edge components in the second step. Therefore, the prediction accuracy of the pixel value is improved and the prediction error is reduced. Pixel value prediction is a necessary technique for various applications such as image magnification and confidential data concealment. Experimental results show that the proposed method has higher prediction accuracy and fewer prediction error. Therefore, the proposed technique can be effectively used for applications such as image magnification and confidential data concealment.

• 한국신뢰성학회지:신뢰성응용연구
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• 제17권1호
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• pp.28-37
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• 2017

Purpose: This paper proposes a procedure that may infer and identify interaction failures in a module. Methods: In design FMEA, we defined an interaction model between components and proposed a method for selecting a single component by using the standard specification classification table and four methods for choosing the related components. We also introduced the function tree for function and requirement characteristic analysis and proposed utilization of standard stress lists and 1st and 2nd stress analysis tables to determine the effect the stress analysis has on interactions. Finally, the interaction mechanism diagram was proposed and used to infer the failure mechanism. Process FMEA also established procedures in a similar way. Results: We established a procedure for predicting the failure mode due to interaction between components based on Company A's multi-step FMEA procedure. Conclusion: By applying the proposed interaction FMEA procedure to the development model, we were able to confirm the effect of the new derivation on the failure mode of interaction, which was not predicted by the existing FMEA.

• 한국연초학회지
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• 제15권1호
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• pp.98-105
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• 1993

The chemical components of tobacco stalk, stems of tobacco caltivations, were analyzed and reconstituted tobacco sheet were made from the stalk and tobacco hyproducts by rolled and paper reconstitute tobacco sheet making process. The results were summarized as follow 1. In the viewpoint of chemical components, nicotine, total nitrogen and ash content of stalk were lower than those of stems, but crude fiber was two times higher than stems. 2. Reconstituted tobacco sheet of tobacco stalk blended were improved fragility and specific gravity than those of control. 3. Smoke components delivery of cigarette made from reconstituted tobacco sheet of tobacco stalk blended were similar to control cigarette. 4. According to the result of ranking preference test for control and sample cigarette, were not recognized significant at 5 percent level. 5. According to the result of areas test for control and sample cigarette, were not recognized significant at 5 percent level. 6. Optimum stalk blend ratio of reconstituted tobacco sheet manufacturing was from about 20 to 40% to the rolled sheet, and was from about 5 to 10% to the paper making process tobacco sheet.

• 한국자동차공학회논문집
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• 제11권2호
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• pp.31-39
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• 2003

Numerical analysis for valve train dynamics of an internal combustion engine is presented. The components of the valve train are modeled by finite element techniques, and the dynamic contacts between the components are analyzed by the solution strategies of differential algebraic equations. Also an iterative scheme similar to the augmented Lagrange multiplier method is employed to enforce the contact constraints. It is shown that the contact and separation between the components of the valve train can be computed by the finite element techniques, and the numerical examples are presented to demonstrate the efficiency of the solution.