• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -2
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• pp.743-746
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• 2002

This paper proposes the design of a current-mode CCII-based 2$\^$nd/ _order bandpass biquad filter from a grounded series capacitor and frequency-dependent negative conductor ( C-D ) immittance function simulator using the macro model of a commercial available CCII+, AD844, from Analog Devices, Inc. The results are compared with the other results those are designed using ideal model of CCII-. The gain and phase deviations; due to the effects of passive sensitivity, active sensitivity, gain sensitivity and component variability; are considered using Monte-Carlo analysis of PSpice program.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1997년도 춘계학술대회논문집
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• pp.159-164
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• 1997

The optimal conditions were investigated in order to manufacture the light automotive body parts using the semi-solid forging process by the finite element nalysis. Considering about macro-segregation cause to difference of relative velocity between solid phase and liquid phase, solidificational phenomenon cause to heat transfer from die and export of the latent heat, so solid fraction updating algorithm can be proposed. The rigid thermo-viscoplastic finite element analysis was carried out according to die temperature with proposed algorithm, so availability of forming part were understood. The finite element program can be used to the analysis of semi solid forging process.

• 통상정보연구
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• 제12권4호
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• pp.25-45
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• 2010

The objective of this paper is to review the mechanics of how global e-trade practices can affect a firm's performance. It is well known that the introduction of global e-trade systems can save transaction costs at the macro level. However this study is extended at micro level by determining whether global trade transaction costs influence positively or negatively in exporting firms performances at firm level. A theoretical framework is suggested for determining the usage and performance of global e-trade with the global e-trade barriers. An empirical analysis of South Korean exporting firms has been undertaken. This paper concludes that the global e-trade has yet to overcome the barriers resulting from the transaction costs and asset specificity. In this regard, appropriate action like intensive education and training program should be implemented in order to make South Korea's global e-trade more matured.

• 한국식품위생안전성학회지
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• 제12권3호
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• pp.210-216
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• 1997

The prevention of oxidative degradation in fats and oils is largely controlled by the use of synthetic phenolic antioxidants. Antioxidants, BHA: 2-&-3-tert-butyl-4-hydroxyanisol, BHT: 3,5-di-tert-butyl-4-hydroxytoluene, TBHQ: tert-butylhydroquinone, PG: propyl gallate, PTG: pentyl gallate, OG:octyl gallate, were extracted from fatty foods with hexane and from hexane layer to presaturated acetonitrile with hexane. The polar phenolic hydroxyl groups of antioxidants were silylated with MSTFA and injected to Gas Chromatography/Mass Spectrometry. The calibration plots were linear in the investigated range, 0.1~10.0 $\mu\textrm{g}$/g. The limit of detection for 6 phenolic antioxidants was 0.1 $\mu\textrm{g}$/g. Recoveries and reproducibilities from samples fortified at 1.0 $\mu\textrm{g}$/g were in the range of 70~90% and 0.5~13%, respectively. The simultaneous determination of phenolic antioxidants in fatty foods using GC/MS-SIM mode and macro program was described.

• 한국식품위생안전성학회지
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• 제14권2호
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• pp.140-145
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• 1999

Analytical method for preservatives in food was developed using gas chromatography/mass spectrometry (GC/MS). Propionic acid, sorbic acid, benzoic acid, ethyl salicylate, ethyl p-hydroxy benzoate, iso-propyl p-hydroxy benzoate, n-propyl p-hydroxy benzoate, iso-butyl p-hydroxy benzoate, n-butyl p-hydroxy benzoate, p-hydroxy benzoic acid and dehydro acetic acid were extracted from cooling beverage with diethyl ether. The polar hydroxyl and carboxyl groups of food preservatives were derivatized with N-methyl-N-tert-butyldimethylisilyl-trifluoroscetamide (MTBSTFA) to form the corresponding tert-bytyldimethyl-silylated derivatives, and submitted to GC/MS analysis. The mass spectra of the derivatives were investigated for the selection of monitoring ions for multi-residue analysis of 11 preservatives by GC/MS. The macro program was also developed for the qualitative analysis of these preservatives in food.

• 터널과지하공간
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• 제8권4호
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• pp.342-350
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• 1998

시추공 텔레뷰어에 의해 획득된 시추공벽 영상을 이용하여 암반내 절리 구조 특성을 해석하고자 하였다. 절리구조의 특성으로서 발달된 절리군의 방향성 및 거칠기의 산정은 영상분석을 통한 절리궤적의 추적에 의하였으며, 산정된 절리군의 JRC 값과 추정된 역학적 상수들로부터 Barton-Bandis 모델에 의해 절리강성을 추정하고 자료들을 종합하여 암반 수치해석 모델링용 절리구조도를 작성하였다. 시추공벽 절리궤적의 추적 효율성을 높이기 위하여 영상 분석기에 내장된 함수를 이용한 최적의 매크로 프로그램과 걸칠기 산정 프로그램, 절리구조도 작성용 프로그램을 완성하였다.

• Computers and Concrete
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• 제23권1호
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• pp.25-36
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• 2019

In this paper, an algorithm is presented to simulate numerically the reinforced concrete (RC) columns having any geometric form of section, loaded eccentrically along one or two axes. To apply the algorithm, the columns are discretized into two macro-elements (MEs) globally and the critical sections of columns are discretized into fixed rectangular finite elements locally. A proposed triple simultaneous dichotomy convergence method is applied to find the equilibrium state in the critical section of the column considering the three strains at three corners of the critical section as the main characteristic variables. Based on the proposed algorithm a computer program has been developed for simulation of the nonlinear behavior of the eccentrically-loaded columns. A good agreement has been witnessed between the results obtained applying the proposed algorithm and the experimental test results. The simulated results indicate that the ultimate strength and stiffness of the RC columns increase with the increase in axial force value, but large axial loads reduce the ductility of the column, make it brittle, impose great loss of material, and cause early failure.

• Human Ecology Research
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• 제57권2호
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• pp.213-224
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• 2019

This study investigates the effect of depressive vulnerability on the interpersonal problems of university students. We explore the moderating effects of ego-resilience on the relation between depressive vulnerability and interpersonal problems. We selected 380 university students as participants from Daegu and Gyeongsan cities. Collected data was analyzed by descriptive statistics, Pearson's correlation, moderating effect with SPSS 23.0. PROCESS, a SPSS macro program developed by Hayes (2013). The findings are as follows. First, there were significant correlations between non-sociability and dependency, self-criticism, non-self-assertiveness, over-consideration, dominance, personal relations, emotion control, and optimism. Second, ego-resilience was found to moderate the relationship between depressive vulnerability and non-self- assertiveness, over-consideration, and dominance among university students. This study suggests that intervention to address ego-resilience are important to resolve the interpersonal problems of university students.

• International Journal of Advanced Culture Technology
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• 제10권4호
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• pp.245-254
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• 2022

This study is a study to empirically verify the mediating effect on college life adaptation and career preparation behavior of college students. The purpose of this study is to empirically analyze the multi-mediated effects of major satisfaction, job stress, and self-directed learning. For this study, 216 university students were enrolled. For the collected data, SPSS Process macro was used. The result is as follows. First, there were multiple parallel mediating effects and multiple serial mediating effects on major satisfaction, job stress, and self-directed learning between college life adaptability and career preparation behavior. Second, the path of simple mediation and double mediation effect was found between college life adaptation and career preparation behavior. Based on the research, the necessity of revitalizing the program for revitalization of teaching activities and industry-academic cooperation activities in the major field and improvement of career preparation behavior and university life adaptation ability and follow-up research were suggested.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2023년도 제68차 하계학술대회논문집 31권2호
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• pp.675-678
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• 2023

본 연구는 팀기반학습을 활용한 교과목을 수강한 간호대학생 56명을 대상으로 동료평가와 학업성취도와의 관계에서 수업몰입의 매개효과를 검정하였다. 매개효과 분석은 PROCESS macro Program의 model 4를 부트스트래핑(bootstrapping)을 이용하여 검정하였다. 분석 결과는 첫째, 동료평가, 수업몰입과 학업성취도 간에 유의한 정적 상관이 있는 것으로 나타났다. 둘째, 수업몰입은 동료평가가 학업성취도에 미치는 영향을 부분매개 하는 것으로 확인되었다. 동료평가가 간호대학생을 위한 TBL 과정에서 수업몰입과 팀워크를 촉진하고 궁극적으로 학업성취도를 향상시키는 효과적인 도구가 될 수 있음을 시사하며, 교수자가 학생의 학습성과를 개선할 수 있는 보다 효과적인 교육 전략 및 개입을 개발하는 데 도움이 될 수 있다.