• 대한수학회보
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• 제45권1호
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• pp.23-31
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• 2008

In this paper, we investigate nonoscillatory solutions of a class of higher order neutral nonlinear difference equations with positive and negative coefficients $\Delta^m(x(n)+p(n)x(\tau(n)))+f_1(n,x(\sigma_1(n)))-f_2(n,x(\sigma_2(n)))=0,\;n{\geq}n_0$. Some sufficient conditions for the existence of nonoscillatory solutions are obtained.

• Journal of applied mathematics & informatics
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• 제31권1_2호
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• pp.199-209
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• 2013

In this paper, we study the oscillation problem of the following higher-order neutral differential equation with positive and negative coefficients and mixed arguments $$z^{(n)}(t)+q_1(t)|x(t-{\sigma}_1)|^{\alpha-1}x(t-{\sigma}_1)+q_2(t)|x(t-{\sigma}_2)|^{\beta-1}x(t-{\sigma}_2)=e(t)$$, where $t{\geq}t_0$, $z(t)=x(t)-p(t)x(t-{\tau})$ with $p(t)$ > 0, ${\beta}>1>{\alpha}>0$, ${\tau}$, ${\sigma}_1$ and ${\sigma}_2$ are real numbers. Without imposing any restriction on ${\tau}$, we establish several oscillation criteria for the above equation in two cases: (i) $q_1(t){\leq}0$, $q_2(t)>0$, ${\sigma}_1{\geq}0$ and ${\sigma}_2{\leq}{\tau}$; (ii) $q_1(t){\geq}0$, $q_2(t)<0$, ${\sigma}_1{\geq}{\tau}$ and ${\sigma}_2{\leq}0$. As an interesting application, our results can also be applied to the following higher-order differential equation with positive and negative coefficients and mixed arguments $$x^{(n)}(t)+q_1(t)|x(t-{\sigma}_1)|^{\alpha-1}x(t-{\sigma}_1)+q_2(t)|x(t-{\sigma}_2)|^{\beta-1}x(t-{\sigma}_2)=e(t)$$. Two numerical examples are also given to illustrate the main results.

• Kyungpook Mathematical Journal
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• 제47권1호
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• pp.1-20
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• 2007

In this paper, oscillation and nonoscillation criteria are established for nonlinear neutral delay differential equations with several positive and negative coefficients $$[x(t)-R(t)x(t-r)]^{\prime}+\sum_{i=1}^{m}Pi(t)H_i(x(t-{\tau}_i))-\sum_{j=1}^{n}Q_j(t)H_j(x(t-{\sigma}_j))=0$$. Our criteria improve and extend many results known in the literature. In addition we prove that under appropriate hypotheses, if every solution of the associated linear equation with constant coefficients, $$y^{\prime}(t)+\sum_{i=1}^{m}(p_i-\sum_{k{\in}J_i}qk)y(t-{\tau}_i)=0$$, oscillates, then every solution of the nonlinear equation also oscillates.

• 한국의류산업학회지
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• 제7권5호
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• pp.509-518
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• 2005

In recent years retail competition has intensified, generally as a consequence of technologies, more sophisticated management practices and industry consolidation. An understanding of current customers' loyalty intentions and their determinants is an important basis for the identification of optimal retailer actions. The focus of this study is to examine the links between patronage intention and the effects of various antecedents of current customers' store loyalty intentions in fashion store. 340 female universities students living in Seoul were analyzed by utilizing multiple regressions to investigate the predictability of each of the 4 different sets of variables(consumer value, source of information, clothing benefits, importance of store attributes) on four patronage intentions of apparel shopping(discount store, speciality store, conventional market, Fashion shopping mall). Four factors were significant in predicting conventional market patronage intention. Brand had a negative coefficient, while price, social affiliation, store fashion service/promotion had positive coefficients. Fashion shopping mall were predicted by five factors:brand had a negative coefficient, while media, social affiliation, price, uniqueness had positive coefficients. For specialty store, four factors were significant: brand had a negative coefficient, while store fashion service/promotion, personal sources, uniqueness had positive coefficients. Four factors were significant in predicting discount store patronage intention :price, store fashion service/promotion, social affiliation, variety of price & product had positive coefficients. Despite the relatively low $r^2s$, all four variables appeared to have, to some degree, predictability of choosing among four different types of store for apparel shopping. Based on the results, patronage intention profiles for four retail stores were developed. Marketing implications are discussed.

• 지역사회간호학회지
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• 제30권4호
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• pp.571-580
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• 2019

Purpose: The purpose of this study is to examine the mediating effects of emotional venting via instant messaging (IM) and positive emotion in the relationship between negative emotion and depression. Methods: Online survey was conducted in Korea between 2 April and 7 April 2019. To obtain samples with representativeness, data were gathered by the professional research firm. A total of 250 Koreans were participated in this study. The collected data were analyzed using descriptive statistics, Pearson's correlation coefficients, and SPSS PROCESS macro to test the mediating effects. Results: This study analyzed the direct/indirect effects of negative emotion on emotional venting via IM, in the relationship between positive emotion and depression. Negative emotion had indirect effects on depression through emotional venting via IM and positive emotion. Both emotional venting via IM and positive emotion had dual mediating effects in the influence of negative emotion on depression. Conclusion: These results suggest that it is important to manage negative emotion to prevent depression. Also, this study confirmed that emotional venting via IM is a powerful factor influencing emotional recovery.

• 생물환경조절학회지
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• 제1권1호
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• pp.28-36
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• 1992

The wind pressure distributions were analyzed to provide fundamental criteria for the structural design on e single-span arched house according to the wind directions through the wind tunnel experiment. In order to investigate the wind force distributions, the variation of the wind force coefficients, the mean wind force coefficients, the drag force coefficients and the lift force coefficients were estimated by using the experimental data. The results obtained are as follows: 1. When the wind direction was normal to the wall, the maximum positive wind pressure along the height of the wall occurred approximately at two-thirds of the wall height because of the effects of boundary layer flow. 2. When the wind direction was 30$^{\circ}$ to the wall, the maximum positive wind force occurred at the windward edge of the wall. When the wind direction was parallel to the wall, the maximum negative wind force occurred at the windward edge of the wall. 3. The maximum negative wind force along the width of the roof appeared around the width ratio, 0.4, and that along the length of the roof appeared around the length ratio, 0.5. 4. According to the results of the mean wind force coefficients analysis, the maximum negative wind force occurred on the roof at the wind direction of 30$^{\circ}$. 5. The wind forces at the wind direction of 30$^{\circ}$ instead of 0$^{\circ}$ are recommended in the structural design of supports for a house. 6. To prevent partial damage of a house structure by wind forces, the local wind forces should be considered to the structural design of a house.

• Korean Membrane Journal
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• 제7권1호
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• pp.67-70
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• 2005

It is well known as the role of ion exchange membrane with functional group in membrane matrix. Recently, we were reported that the charged mosaic membrane within parallel array of negative and positive charge groups. In this study we are reported the properties for the various transport coefficients of metal and heavy metal ions across charged mosaic membrane based on non-equilibrium thermodynamics is not based on equilibrium state.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2003년도 춘계학술대회 논문집
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• pp.120-122
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• 2003

In this study, an experiment was conducted in order to investigate the feasibility and effectiveness of and on-line subjective assessment (OLSA) system. The present study compared Galvanic Skin Response (GSR) with the OLSA by presenting 28 subjects in their 20s with pictures arousing either positive or negative sensibility. According to the correlation coefficients, changes in subjective sensibility caused by the positive visual stimulus were related more closely to GSR, from the positive visual stimulus, and changes in subjective sensibility caused by the negative visual stimulus were related more closely to GSR from the negative visual stimulus. In conclusion, the most remarkable characteristic of the present system is that it not only assesses the average sensibility when stimuli are presented, but also shows the changing strength of sensibility over time.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권5호
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• pp.2484-2498
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• 2017

Various types of social media make the people share their personal experience in different ways. In some social networking sites. Some users post their reviews, some users can support these reviews with comments, and some users just rate the reviews as kind of support or not. Unfortunately, there is rare explicit negative comments towards other reviews. This means if there is a link between two users, it must be positive link. Apparently, the negative link is invisible in these social network. Or in other word, the negative links are redundant to positive links. In this work, we first discuss the feature extraction from social media data and propose new method to compute the distance between each pair of comments or reviews on social media. Then we investigate whether we can predict negative links via regression analysis when only positive links are manifested from social media data. In particular, we provide a principled way to mathematically incorporate multi-facet data in a novel framework, Constructing Negative Links, CsNL to predict negative links for discovering the hidden information. Additionally, we investigate the ways of solution to general negative link predication problems with CsNL and its extension. Experiments are performed on real-world data and results show that negative links is predictable with multi-facet of social media data by the proposed framework CsNL. Essentially, high prediction accuracy suggests that negative links are redundant to positive links. Further experiments are performed to evaluate coefficients on different kernels. The results show that user generated content dominates the prediction performance of CsNL.

• 한국가금학회지
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• 제50권1호
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• pp.15-22
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• 2023

본 연구는 토종 종계의 육성기 체중과 산란 능력 간의 연관성을 규명하고자 성숙 이전 주령별 체중과 이들의 초산일령, 산란율 및 난중과의 상관 관계를 분석하였다. 공시계는 (주)한협원종이 보유한 신품종 토종 종계 1,384수로써 발생부터 20주령까지의 체중과 초산일령, 초산이후 50주령까지의 일계 산란율 및 산란지수, 32주령 및 50주령 난중을 분석 대상으로 하였다. 분석 결과, 육성 초기 체중과 초산일령 간에는 정(positive)의 상관이, 육성 후기 체중과 초산일령 간에는 부(negative)의 상관이 나타났다. 육성기 체중과 일계 산란율 및 산란지수 간에는 비슷한 상관계수를 보이고, 육성전기 체중과 산란율 간에는 부의 상관이, 육성 후기 체중과는 정의 상관을 보였다. 육성기 체중과 32주령 난중 간에는 거의 상관 관계가 없는 것으로 나타났고, 50주령 난중과는 낮은 정의 상관을 보였다. 결론적으로 토종 종계에 있어서 8주령 이전까지의 육성 초기 체중과 산란 능력 간에는 거의 연관성이 없는 것으로 보여지고, 12주령 이후 육성 후기 체중과 산란 능력 간에는 정의 상관이 있는 것으로 나타났다. 이는 육성 후기 때 병아리의 체중이 증가할수록 성 성숙이 빠르고, 산란율도 높고 난중도 증가함을 시사한다. 따라서 토종 종계 모계의 경우 육성 후기 병아리의 체중 관리가 매우 중요하고, 이때 종계들의 체중이 표준 체중 이상이 되도록 유지하여야 한다.