• Journal of applied mathematics & informatics
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• 제23권1_2호
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• pp.141-152
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• 2007

In this paper a numerical method is presented to solve singularly perturbed two points boundary value problems for second order ordinary differential equations consisting a discontinuous source term. First, in this method, an asymptotic expansion approximation of the solution of the boundary value problem is constructed using the basic ideas of a well known perturbation method WKB. Then some initial value problems and terminal value problems are constructed such that their solutions are the terms of this asymptotic expansion. These initial value problems are happened to be singularly perturbed problems and therefore fitted mesh method (Shishkin mesh) are used to solve these problems. Necessary error estimates are derived and examples provided to illustrate the method.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.264-264
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• 2017

Legumes are good sources of various nutrients. Among legumes, soybean and its flour are accessible foods to consumers. However, in case of soybean flour, there is a disadvantage of easily going rancid. Thus, this study aimed to investigate how the quality of soybean flour changes during storage according to the packaging materials and storage temperatures. The raw and roasted soybean flours were packed in two types of packaging, polyethylene (PE) and polypropylene (PP) film bags respectively, and stored at three different storage temperatures (4, 20, and $45^{\circ}C$) for 1 year. The acid value, conjugated diene value, peroxide value, p-anisidine value, thiobarbituric acid (TBA) value, lipoxygenase activity, and fatty acid content of raw and roasted soybean flours were measured at the point of starting storing, and after 1, 2, 4, 8, and 12 weeks of storage. The acid value of soybean flour was increased for 4 weeks and thereafter significantly decreased (p < 0.0001). The conjugated diene value was significantly increased after 4 weeks storage at $45^{\circ}C$ with PE and PP film bags (p < 0.0001). The peroxide value had no changes during 4 weeks storage at $45^{\circ}C$ with PE and PP film bags, and then those was dramatically increased after 8 weeks (p < 0.0001). The p-anisidine values in all of storage conditions were decreased after 4 weeks. Lipoxygenase activity was decreased at 12 weeks storage at $20^{\circ}C$ and $45^{\circ}C$ with PP film bags. Acid value had positive correlations with p-anisidine value (r = 0.30 and p < 0.0001) and lipoxygenase activity (r = 0.36 and p < 0.0001), and had negative correlations with conjugated diene value (r = -0.45 and p < 0.0001) and peroxide value (r = -0.25 and p < 0.001). Conjugated diene value had a high positive correlation with peroxide value (r = 0.76 and p < 0.0001), but that had a negative correlation with lipoxygenase activity (r = -0.51 and p < 0.0001). Peroxide value had negative correlations with p-anisidine value (r = -0.20 and p < 0.01) and TBA value (r = -0.15 and p < 0.05). The degree of reduction in fatty acid content of raw soybean flour was higher than the roasted soybean flour during the storage. Total fatty acid content had positive correlations with acid value (r = 0.45 and p < 0.0001) and p-anisidine value (r = 0.58 and p < 0.0001), but had a weak negative correlation with conjugated diene value (r = -0.19 and p < 0.01). This study showed how the rancidity of the raw and roasted soybean flours progressed during storage. Thus, our findings can be used as base data to do a further study of finding and developing more stable storage conditions of the soybean flour.

• 수산해양기술연구
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• 제46권4호
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• pp.376-391
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• 2010

To investigate seasonal variation and species composition by depth layers in the deep sea ecosystem of the East Sea of Korea, bottom trawl survey was conducted at 4 depth layers during spring and autumn from 2007 to 2009. A total of 47 species were collected and were composed of 23 fish species, 9 crustacea, 6 cephalopoda and 9 gastropoda. The main dominant species at each depth layers were Chionoecetes opilio in 300m, Berryteuthis magister in 500m, Chionoecetes japonicus in 700m and 900m. In spring, richness indices (R) showed low value of 2.01 in 500m depth, and high value of 2.16 in 300m depth. Diversity indices (H') showed low value of 1.53 in 300m depth, and high value of 2.09 in 700m depth. Dominance indices (D) showed low value of 0.15 in 700m depth, and high value of 0.31 in 300m depth. In Autumn, richness indices showed low value of 1.48 in 900m depth, and high value of 2.69 in 300m depth. Diversity' indices (H') showed low value of 1.13 in 300m depth, and high value of 2.23 in 700m depth. Dominance indices (D) showed low value of 0.14 in 700m depth, and high value of 0.54 in 300m depth. In spring, similarity analysis in each depth layers showed the difference between 900m and othe depth layer, on the contrary 500m and 700m showed the similarity. In autumn, similarity analyssis in each depth layers showed the difference between 700m and other depth layers, on the contrary 300m and 500m showed the similarity.

• 한국융합학회논문지
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• 제11권3호
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• pp.219-226
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• 2020

본 연구는 K항공사를 이용하는 고객을 대상으로 고객가치가 브랜드 동일시 및 충성도에 미치는 영향관계를 분석하고자 연구모형을 설정하였다. 이론연구의 고찰을 통해 변수를 추출하였으며 각 변수간의 관계를 살펴보기 위해 구조방정식 모형을 활용하였다. 실증분석 결과는 아래와 같다. 첫째, 고객가치 중 기능적 가치와 감성적 가치가 브랜드 동일시에 모두 유의한 영향을 미치는 것으로 나타나 가설 1은 채택되었다. 둘째, 현재의 소비자는 제품이나 서비스의 선택에 있어 감성적인 면을 더 추구한다는 것을 확인하였다. 즉 자아 이미지와 동일하거나 자신의 가치관 혹은 라이프 스타일에 일치한다고 생각하는 항공사 브랜드를 이용함으로써 항공사와의 브랜드 동일시를 추구하고 있다. 셋째, 고객 가치 중 기능적 가치와 감성적 가치 모두 브랜드 충성도에 영향을 미치지 않는 것으로 나타나 고객가치는 브랜드 동일시를 통해 충성도가 강화됨을 알 수 있다. K항공은 소비자들의 브랜드 충성도를 상승시키기 위해서는 다른 매개변수의 역할도 고려되어야 하겠지만 고객의 브랜드 동일시 제고에 관심을 가져야 할 것으로 사료된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.49-50
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• 2011

본 논문에서는 WT(Wavelet Transform)와 SVD(Singular Value Decomposition)를 함께 사용한 WSVD(Wavelet Singular Value Decomposition)를 이용하여 발전기 탈락 시의 전압 변동 특성을 분석하였다. WSVD 특성 분석을 위해 부산 지역의 345kV급 송전계통을 EMTP-RV로 모델링하였으며, 이 계통모델에서 발전기 탈락을 모의하였다. MATLAB을 통해 이 때 측정된 전압의 WSVD를 계산하여 발전기 탈락에 따른 특성을 분석하였다.

• 한국의류학회지
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• 제34권2호
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• pp.226-241
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• 2010

This study details the history and characteristics of consumption values, text style analyses, and appeal types expressed in magazine commercials from 1955 to 2008. This study analyzes the level of the social structure of commercial expression for each period. Consumption values based on the categories of consumption values by Sheth (1991) were classified through a total commercials analysis. Analyses on closing types of sentences, types of sentences, and rhetorical figures were executed focusing on headline text and text style. Appealing types were composed of rational, emotional, and ethical appeals. For analysis, the crosstab analysis and chi-square test of SPSS are used. The results are as follow. Seven values were constructed, functional value, social value, emotional value, conditional value, epistemic value, fashionable value, and indistinct value. The ratio of emotional value was the highest and functional value, epistemic value conditional value, fashionable value, social value, and indistinct value followed. The emotional value social value, conditional value, fashionable value, and epistemic value that focused on the emotion of consumers increased, while the functional value decreased. Sentences that use narrative styles, hyperboles, and metaphors that increased the interest of readers were dominantly used in the headline texts. For sentence expression, a declarative sentence in a sentence type, exciting curiosity in the expression method where hyperbole and figures of speech in rhetorical expressions are used most often. Emotional appeal was used almost twice more than the reasonable appeal for appeal types of the total commercial. The lower level of reasonable appeal is information that provides the product function. Interest and expression (such as pleasure and achievement) were used most often for emotional appeal. These results show that the most important issue is the emotional value in consumption in understanding the consumer. Marketing managers should also be aware of the functional value as well as an emotional value.

• 한국환경복원기술학회지
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• 제21권1호
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• pp.31-40
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• 2018

Since the Millennium Ecosystem Assessment Report was published in 2005, the conflict between development and the preservation of the ecological environment has turned to paying attention to value assessments in rational decision-making. In recent years, the concept of ecosystem services has been recognized as a viable one for making significant decisions. However, a trade-off between increase and decrease occurs between the ecosystem services sub-categories (cultural service, regulating service, supporting service, and provisioning service), for which research centering on target sites is needed. To this end, the present study aims to investigate the trade-off relationship between service categories to search for reasonable decision-making strategies. As the research method, a survey was conducted using the translated version of SoIVES(Social Value for Ecosystem Services) 3.0 questionnaire of the United States Geological Survey. The research findings demonstrate the economic value, based on the derived monetary value of each service category, the economic value of the target site was compared among landscape aesthetic value 8,050,000 won, recreation value 6,750,000 won, biodiversity value 4,610,000 won, healing value 3,970,000 won, life-sustaining value 2,090,000 won, and productive value 220,000 won. And then the primarily recognized value criteria of the Tancheon ecosystem services illustrate landscape aesthetic and recreation value. Besides, this study illustrates visualized trade-off relationships based on user perception, and the derived relations illustrate the trade-off relationship between the cultural service, regulating service, supporting service, and provisioning service, as well as relationships between the components of the sub-categories.

• 가족자원경영과 정책
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• 제13권2호
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• pp.129-151
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• 2009

The first purpose of this study was to reveal the types of shopping value of college students. The second purpose was to examine the change in the perception and management behaviors related to credit cards according to the types of shopping value. The third purpose was to examine the effects of shopping value on perception and management behaviors on credit cards. The data were collected from 392 college students in Seoul by a self-administered questionnaire. Analyses including frequency, mean, factor analysis, Cronbach's alpha, Pearson's correlation analysis, Crosstabulation analysis, analysis of variance, K-means Cluster analysis and Multiple linear regression were conducted using SPSS WIN12.0. The major findings were as follows. First, college students can be categorized into 3 types of shopping values by K-means Cluster analysis of 14 items. The groups were entitled the hedonistic shopping value, the utilitarian shopping value, and the saving shopping value. Second, positive perception and management behaviors related to credit cards were different depending on the types of shopping value. The hedonistic shopping value group had a higher level of positive perception of credit cards and a lower level of credit card management, compared with the other groups. The saving shopping value group had higher levels of both positive perception and management of credit cards. Among the three groups, the utilitarian shopping group had the lowest level of positive perception of credit cards, despite having ahigher level of credit card management. Lastly, the most effective variance on credit card management was the utilitarian shopping value. These results suggest that a healthy shopping value is very important for having a healthy perception and management of credit cards, because shopping value is a critical variance to affect perception and management of credit cards.

• 품질경영학회지
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• 제31권4호
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• pp.203-218
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• 2003

The ongoing debate over IT productivity has revealed paradoxical effects of IT. This study proposes that IT business value is paradoxical structured. IT impacts are not easy to generalize according to one perspective or paradigm. This study assumes multiplicity in the phenomenon of IT value and explores effects of these multiple interpretations. The study seeks to understand organizational performance. Hypotheses are developed to test the relationship between competing interpretations of IT value and organizational performance. The purpose of this study is to determine whether or not senior managers perceive IT value on the basis of divergent managerial value frames.

• Journal of Communications and Networks
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• 제12권5호
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• pp.475-479
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• 2010

The clipping value, defined as the log-likelihood ratio (LLR) in the case wherein all the list of candidates have the same binary value, is investigated, and an effective method to estimate it is presented for iterative tree search detection. The basic principle behind the method is that the clipping value of a channel bit is equal to the LLR of the maximum probability of correct decision of the bit to the corresponding probability of erroneous decision. In conjunction with multilevel bit mappings, the clipping value can be calculated with the parameters of the number of transmit antennas, $N_t$; number of bits per constellation point, $M_c$; and variance of the channel noise, $\sigma^2$, per real dimension in the Rayleigh fading channel. Analyses and simulations show that the bit error performance of the proposed method is better than that of the conventional fixed-value method.