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Determinants of Nicotine Dependence in Chronic Obstructive Pulmonary Disease

  • Sim, Yun Su;Lee, Jin Hwa;Kim, Ki Uk;Ra, Seung Won;Park, Hye Yun;Lee, Chang-Hoon;Kim, Deog Kyeom;Shin, Kyeong-Cheol;Lee, Sang Haak;Hwang, Hun Gyu;Ahn, Joong Hyun;Park, Yong Bum;Kim, Yu-Il;Yoo, Kwang Ha;Jeong, Ina;Oh, Yeon-Mok;Lee, Sang-Do;KOLD Investigators
    • Tuberculosis and Respiratory Diseases
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    • v.80 no.3
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    • pp.277-283
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    • 2017
  • Background: Smoking cessation is the most powerful intervention to modify progress of chronic obstructive pulmonary disease (COPD), and nicotine dependence is one of the most important determinants of success or failure in smoking cessation. We evaluated nicotine dependence status and investigated factors associated with moderate to high nicotine dependence in patients with COPD. Methods: We included 53 current smokers with COPD in the Korean Obstructive Lung Disease II cohort enrolled between January 2014 and March 2016. Nicotine dependence was measured by using Fagerstrom test for nicotine dependence (FTND). Cognitive function was assessed by Korean version of Montreal Cognitive Assessment. Results: The median FTND score was 3, and 32 patients (60%) had moderate to high nicotine dependence. The median smoking amount was 44 pack-years, which was not related to nicotine dependence. Multiple logistic regression analysis revealed that high education status (odds ratio, 1.286; 95% confidence interval, 1.036-1.596; p=0.023), age <70 (odds ratio, 6.407; 95% confidence interval, 1.376-29.830; p=0.018), and mild to moderate airflow obstruction (odds ratio, 6.969; 95% confidence interval, 1.388-34.998; p=0.018) were related to moderate to high nicotine dependence. Conclusion: Nicotine dependence does not correlate with smoking amount, but with education level, age, and severity of airflow obstruction. Physicians should provide different strategies of smoking cessation intervention for current smokers with COPD according to their education levels, age, and severity of airflow obstruction.

A Reliable Protocol for transfection of mature primary hippocampal neurons using a neuron-glia co-culture system (신경세포-신경교세포 공동배양을 이용한 성숙한 해마신경세포의 효율적인 형질전환 방법)

  • Lee, Hyun-Sook;Cho, Sun-Jung;Jung, Yong-Wook;Jin, Ing-Nyol;Moon, Il-Soo
    • Journal of Life Science
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    • v.17 no.2 s.82
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    • pp.198-203
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    • 2007
  • DNA transfection is a powerful tool for studying gene functions. The $Ca^{2+}$-phosphate precipitation remains one of the most popular and cost-effective transfection techniques. Mature neurons are more resistant to transfection than young ones and most other cell types, and easy to die if microenvironment changes. Here, we report a transfection protocol for mature neurons. The critical modifications are inclusion of glial cells in culture and careful control of $Ca^{2+}$-phosphate precipitation under microscope. Cerebral glial cells were grown until ${\sim}70-80%$ confluence in DMEM/10% horse serum, which was thereafter replaced with serum-free Neurobasal/Ara-C, and 319 hippocampal neurons were plated onto the glial layer Formation of fine $DNA/Ca^{2+}$-phosphate precipitates was induced using Clontech $CalPhos^{TM}$ Mammalian Transfection Kit, and the size ($0.5-1\;{\mu}m$ in diameter) and density(about 10 particles/$100\;{\mu}m^2$) were carefully controlled by the time of incubation in the medium. This modified protocol can be reliably applied for transfection of mature neurons that are maintained longer than two weeks in vitro, resulting in 10-15 healthy transfected neurons per a well of 24-well plates. The efficacy of the protocol was verified by punctate expression of $pEGFP-CaMKII{\alpha}$, a synaptic protein, and diffuse expression of pDsRed2. Our protocol provides a reliable method for transfection of mature neurons in vitro.

The Limitations of the Privatization of Social Security Programs : the American Workers' Compensation Program Case (산재보험 민영화의 한계 : 미국 산재보험 사례)

  • Cho, Young-Hoon
    • Korean Journal of Social Welfare
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    • v.53
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    • pp.31-49
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    • 2003
  • Neo-liberalism, the most influential ideology in the current world, argues for the commercialization of social security programs and for the dissolution of the interventionist welfare state. From the neo-liberal viewpoint, social services become more efficient and more advantageous for recipients, when provided by the market, not by the state. It is also argued that the welfare of all social members is best secured when the market freely operates without any interference from the state. From the neo-liberal point of view, an argument was raised to commercialize the state-administered Workers' Compensation program of Korea in the mid-1990s. This argument was faced with strong resistances from labor unions and social welfare circles, and has disappeared since the economic breakdown and the restructuring of Korean society during the late 1990s. Butr, such an argument can emerge anytime as the nee-liberal ideology become more powerful. This article aims to examine the neo-liberal argument that the privatization of social security programs, through an increases in efficiency, improves the interests of the recipients as well as the whole society. For this, this article attempts to analyze the Workers' Compensation programs of the USA, which, from state to state, are administered by the state government or by private insurance companies. This study can serve as an effective critique for the neo-liberal argument, if it finds that state-administered Workers' Compensation programs are more efficient than those managed by insurance companies. This article's another aim is to assess the controversies over the privatization of the Workers' Compensation program of Korea during the mid to late 1990s. The controversies were more about which viewpoint is right and, in most cases, lacked empirical evidence. This study shall empirically criticize the argument for the privatization of the Workers' Compensation program.

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A Study on the Impact Factors of Contents Diffusion in Youtube using Integrated Content Network Analysis (일반영향요인과 댓글기반 콘텐츠 네트워크 분석을 통합한 유튜브(Youtube)상의 콘텐츠 확산 영향요인 연구)

  • Park, Byung Eun;Lim, Gyoo Gun
    • Journal of Intelligence and Information Systems
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    • v.21 no.3
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    • pp.19-36
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    • 2015
  • Social media is an emerging issue in content services and in current business environment. YouTube is the most representative social media service in the world. YouTube is different from other conventional content services in its open user participation and contents creation methods. To promote a content in YouTube, it is important to understand the diffusion phenomena of contents and the network structural characteristics. Most previous studies analyzed impact factors of contents diffusion from the view point of general behavioral factors. Currently some researchers use network structure factors. However, these two approaches have been used separately. However this study tries to analyze the general impact factors on the view count and content based network structures all together. In addition, when building a content based network, this study forms the network structure by analyzing user comments on 22,370 contents of YouTube not based on the individual user based network. From this study, we re-proved statistically the causal relations between view count and not only general factors but also network factors. Moreover by analyzing this integrated research model, we found that these factors affect the view count of YouTube according to the following order; Uploader Followers, Video Age, Betweenness Centrality, Comments, Closeness Centrality, Clustering Coefficient and Rating. However Degree Centrality and Eigenvector Centrality affect the view count negatively. From this research some strategic points for the utilizing of contents diffusion are as followings. First, it is needed to manage general factors such as the number of uploader followers or subscribers, the video age, the number of comments, average rating points, and etc. The impact of average rating points is not so much important as we thought before. However, it is needed to increase the number of uploader followers strategically and sustain the contents in the service as long as possible. Second, we need to pay attention to the impacts of betweenness centrality and closeness centrality among other network factors. Users seems to search the related subject or similar contents after watching a content. It is needed to shorten the distance between other popular contents in the service. Namely, this study showed that it is beneficial for increasing view counts by decreasing the number of search attempts and increasing similarity with many other contents. This is consistent with the result of the clustering coefficient impact analysis. Third, it is important to notice the negative impact of degree centrality and eigenvector centrality on the view count. If the number of connections with other contents is too much increased it means there are many similar contents and eventually it might distribute the view counts. Moreover, too high eigenvector centrality means that there are connections with popular contents around the content, and it might lose the view count because of the impact of the popular contents. It would be better to avoid connections with too powerful popular contents. From this study we analyzed the phenomenon and verified diffusion factors of Youtube contents by using an integrated model consisting of general factors and network structure factors. From the viewpoints of social contribution, this study might provide useful information to music or movie industry or other contents vendors for their effective contents services. This research provides basic schemes that can be applied strategically in online contents marketing. One of the limitations of this study is that this study formed a contents based network for the network structure analysis. It might be an indirect method to see the content network structure. We can use more various methods to establish direct content network. Further researches include more detailed researches like an analysis according to the types of contents or domains or characteristics of the contents or users, and etc.

A Novel Volumetric Method for Quantitation of Titanium Dioxide in Cosmetics (용량분석법을 이용한 화장품 중 티타늄옥사이드의 정량)

  • Kim, Young-So;Kim, Boo-Min;Park, Sang-Chul;Jeong, Hye-Jin;Chang, Ih-Seop
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.31 no.4 s.54
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    • pp.289-293
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    • 2005
  • Nowadays there are many sun protection cosmetics including organic or inorganic UV filter as an active ingredient. Chemically stable inorganic sunsEreen agents, usually metal oxides, we widely employed in high SPF products. Titanium dioxide is one of the most frequently used inorganic UV filters. It has been used as pigments for a long period of cosmetic history. With the development of micronization techniques, it becomes possible to incorporate titanium dioxide in sunscreen formulations without whitening effect and it becomes an important research topic. However, there are very few works related to quantitations of titanium dioxide in sunscreen products. In this research, we analyzed amounts of titanium dioxide in sunscreen cosmetics by adapting redof titration, reduction of Ti(IV) to Ti(III) and reoxidation to Ti(IV). After calcification of other organic ingredients of cosmetics, titanium dioxide is dissolved by hot sulfuric acid. The dissolved Ti(IV) is reduced to the Ti(III) by adding aluminum metals. The reduced Ti(III) is titrated against a standard oxidizing agent, Fe(III) (ammonium iron(III) sulfate), with potassium thiocyanate as an indicator In order to test accuracy and applicability of the proposed method, we analyzed the amounts of titanium dioxide in four types of sunscreen cosmetics, such as cream, make-up base, foundation and powder, after adding known amounts of titanium dioxide $(1{\sim}25w/w%)$. The percent recoveries of the titanium dioxide in four types of formulations were in the range between 96 and 105%. We also analyzed 7 commercial cosmetic products labeled titanium dioxide as an ingredient and compared the results with those of obtained from ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry), one of the most powerful atomic analysis techniques. The results showed that the titrated amounts were well coincided with the analyzed amounts of titanium dioxide by ICP-AES. Although instrumental analytical methods, ICP-MS (Inductively Coupled Plasma-Mass Spectrometry) and ICP-AES, are the best for the analysis of titanium, it is hard to adopt because of their high prices for small cosmetic companies. It was found that the volumetric method presented here gat e quantitative and reliable results with routine lab-wares and chemicals.

Development and Testing of the Model of Health Promotion Behavior in Predicting Exercise Behavior

  • O'Donnell, Michael P.
    • Korean Journal of Health Education and Promotion
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    • v.2 no.1
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    • pp.31-61
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    • 2000
  • Introduction. Despite the fact that half of premature deaths are caused by unhealthy lifestyles such as smoking tobacco, sedentary lifestyle, alcohol and drug abuse and poor nutrition, there are no theoretical models which accurately explain these health promotion related behaviors. This study tests a new model of health behavior called the Model of Health Promotion Behavior. This model draws on elements and frameworks suggested by the Health Belief Model, Social Cognitive Theory, the Theory of Planned Action and the Health Promotion Model. This model is intended as a general model of behavior but this first test of the model uses amount of exercise as the outcome behavior. Design. This study utilized a cross sectional mail-out, mail-back survey design to determine the elements within the model that best explained intentions to exercise and those that best explained amount of exercise. A follow-up questionnaire was mailed to all respondents to the first questionnaire about 10 months after the initial survey. A pretest was conducted to refine the questionnaire and a pilot study to test the protocols and assumptions used to calculate the required sample size. Sample. The sample was drawn from 2000 eligible participants at two blue collar (utility company and part of a hospital) and two white collar (bank and pharmaceutical) companies located in Southeastern Michigan. Both white collar site had employee fitness centers and all four sites offered health promotion programs. In the first survey, 982 responses were received (49.1%) after two mailings to non-respondents and one additional mailing to secure answers to missing data, with 845 usable cases for the analyzing current intentions and 918 usable cases for the explaining of amount of current exercise analysis. In the follow-up survey, questionnaires were mailed to the 982 employees who responded to the initial survey. After one follow-up mailing to non-respondents, and one mailing to secure answers to missing data, 697 (71.0%) responses were received, with 627 (63.8%) usable cases to predict intentions and 673 (68.5%) usable cases to predict amount of exercise. Measures. The questionnaire in the initial survey had 15 scales and 134 items; these scales measured each of the variables in the model. Thirteen of the scales were drawn from the literature, all had Cronbach's alpha scores above .74 and all but three had scores above .80. The questionnaire in the second mailing had only 10 items, and measured only outcome variables. Analysis. The analysis included calculation of scale scores, Cronbach's alpha, zero order correlations, and factor analysis, ordinary least square analysis, hierarchical tests of interaction terms and path analysis, and comparisons of results based on a random split of the data and splits based on gender and employer site. The power of the regression analysis was .99 at the .01 significance level for the model as a whole. Results. Self efficacy and Non-Health Benefits emerged as the most powerful predictors of Intentions to exercise, together explaining approximately 19% of the variance in future Intentions. Intentions, and the interaction of Intentions with Barriers, with Support of Friends, and with Self Efficacy were the most consistent predictors of amount of future exercise, together explaining 38% of the variance. With the inclusion of Prior Exercise History the model explained 52% of the variance in amount of exercise 10 months later. There were very few differences in the variables that emerged as important predictors of intentions or exercise in the different employer sites or between males and females. Discussion. This new model is viable in predicting intentions to exercise and amount of exercise, both in absolute terms and when compared to existing models.

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Longitudinal analysis of the influence of parent-child relationship on adolescents' academic achievement: With specific focus on the mediating role of self-efficacy and achievement motivation (한국 청소년의 부모자녀관계와 성취에 대한 종단연구: 자기효능감과 성취동기를 중심으로)

  • Young-Shin Park ;Uichol Kim ;Kabsoon Chung
    • Korean Journal of Culture and Social Issue
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    • v.10 no.3
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    • pp.37-59
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    • 2004
  • This study examines longitudinally influences that parents have on their children's academic achievement and the mediating role of various psychological factors. In terms of parents-child relationship, the following variables are examined: Social support from parents, achievement pressure, parental expectation, sense of indebtedness to parents, and respect for parents. For adolescents functioning, the following variables are examined: Efficacy for self-regulated learning, achievement motivation, studying time, and academic achievement. In the first phase of the longitudinal study, a total of 961 Grade 6 students completed a questionnaire. In the second phrase, a total of 856 students completed a questionnaire when they were Grade 7. In the third phrase, a total of 830 students completed a questionnaire when they were Grade 9. In the third phase, a matched sample of 722 fathers and 767 mothers of the adolescents completed a questionnaire. From the sample, 694 matched sample of adolescents, mothers, and fathers have been selected for the following analysis. The results of the path analysis indicate that adolescents' past academic grade was the most powerful predictor of adolescents' current academic achievement. Second, a sense of indebtedness felt towards the parents increased adolescents' achievement motivation, which increased their studying time and which in turn positively affected their academic achievement. Third, adolescents' respect for their parents increased their efficacy for self-regulated learning, which had a positive effect on their academic achievement. Fourth, parental social support increased adolescents' efficacy for self-regulated learning and parental achievement pressure increased adolescents' achievement motivation. Fifth, parental expectation had positive influence on adolescents' academic achievement. Sixth, efficacy for self-regulated learning had direct positive influence on academic achievement. These results indicate that the past achievement is the most important predictor of adolescents' current academic achievement and parent-child relationship and efficacy for self-regulated learning are also important variables that influence adolescents' achievement.

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Measuring Consumer-Brand Relationship Quality (소비자-브랜드 관계 품질 측정에 관한 연구)

  • Kang, Myung-Soo;Kim, Byoung-Jai;Shin, Jong-Chil
    • Journal of Global Scholars of Marketing Science
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    • v.17 no.2
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    • pp.111-131
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    • 2007
  • As a brand becomes a core asset in creating a corporation's value, brand marketing has become one of core strategies that corporations pursue. Recently, for customer relationship management, possession and consumption of goods were centered on brand for the management. Thus, management related to this matter was developed. The main reason of the increased interest on the relationship between the brand and the consumer is due to acquisition of individual consumers and development of relationship with those consumers. Along with the development of relationship, a corporation is able to establish long-term relationships. This has become a competitive advantage for the corporation. All of these processes became the strategic assets of corporations. The importance and the increase of interest of a brand have also become a big issue academically. Brand equity, brand extension, brand identity, brand relationship, and brand community are the results derived from the interest of a brand. More specifically, in marketing, the study of brands has been led to the study of factors related to building of powerful brands and the process of building the brand. Recently, studies concentrated primarily on the consumer-brand relationship. The reason is that brand loyalty can not explain the dynamic quality aspects of loyalty, the consumer-brand relationship building process, and especially interactions between the brands and the consumers. In the studies of consumer-brand relationship, a brand is not just limited to possession or consumption objectives, but rather conceptualized as partners. Most of the studies from the past concentrated on the results of qualitative analysis of consumer-brand relationship to show the depth and width of the performance of consumer-brand relationship. Studies in Korea have been the same. Recently, studies of consumer-brand relationship started to concentrate on quantitative analysis rather than qualitative analysis or even go further with quantitative analysis to show effecting factors of consumer-brand relationship. Studies of new quantitative approaches show the possibilities of using the results as a new concept of viewing consumer-brand relationship and possibilities of applying these new concepts on marketing. Studies of consumer-brand relationship with quantitative approach already exist, but none of them include sub-dimensions of consumer-brand relationship, which presents theoretical proofs for measurement. In other words, most studies add up or average out the sub-dimensions of consumer-brand relationship. However, to do these kind of studies, precondition of sub-dimensions being in identical constructs is necessary. Therefore, most of the studies from the past do not meet conditions of sub-dimensions being as one dimension construct. From this, we question the validity of past studies and their limits. The main purpose of this paper is to overcome the limits shown from the past studies by practical use of previous studies on sub-dimensions in a one-dimensional construct (Naver & Slater, 1990; Cronin & Taylor, 1992; Chang & Chen, 1998). In this study, two arbitrary groups were classified to evaluate reliability of the measurements and reliability analyses were pursued on each group. For convergent validity, correlations, Cronbach's, one-factor solution exploratory analysis were used. For discriminant validity correlation of consumer-brand relationship was compared with that of an involvement, which is a similar concept with consumer-based relationship. It also indicated dependent correlations by Cohen and Cohen (1975, p.35) and results showed that it was different constructs from 6 sub-dimensions of consumer-brand relationship. Through the results of studies mentioned above, we were able to finalize that sub-dimensions of consumer-brand relationship can viewed from one-dimensional constructs. This means that the one-dimensional construct of consumer-brand relationship can be viewed with reliability and validity. The result of this research is theoretically meaningful in that it assumes consumer-brand relationship in a one-dimensional construct and provides the basis of methodologies which are previously preformed. It is thought that this research also provides the possibility of new research on consumer-brand relationship in that it gives root to the fact that it is possible to manipulate one-dimensional constructs consisting of consumer-brand relationship. In the case of previous research on consumer-brand relationship, consumer-brand relationship is classified into several types on the basis of components consisting of consumer-brand relationship and a number of studies have been performed with priority given to the types. However, as we can possibly manipulate a one-dimensional construct through this research, it is expected that various studies which make the level or strength of consumer-brand relationship practical application of construct will be performed, and not research focused on separate types of consumer-brand relationship. Additionally, we have the theoretical basis of probability in which to manipulate the consumer-brand relationship with one-dimensional constructs. It is anticipated that studies using this construct, which is consumer-brand relationship, practical use of dependent variables, parameters, mediators, and so on, will be performed.

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Eurasian Naval Power on Display: Sino-Russian Naval Exercises under Presidents Xi and Putin (유라시아 지역의 해군 전력 과시: 시진핑 주석과 푸틴 대통령 체제 하에 펼쳐지는 중러 해상합동훈련)

  • Richard Weitz
    • Maritime Security
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    • v.5 no.1
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    • pp.1-53
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    • 2022
  • One manifestation of the contemporary era of renewed great power competition has been the deepening relationship between China and Russia. Their strengthening military ties, notwithstanding their lack of a formal defense alliance, have been especially striking. Since China and Russia deploy two of the world's most powerful navies, their growing maritime cooperation has been one of the most significant international security developments of recent years. The Sino-Russian naval exercises, involving varying platforms and locations, have built on years of high-level personnel exchanges, large Russian weapons sales to China, the Sino-Russia Treaty of Friendship, and other forms of cooperation. Though the joint Sino-Russian naval drills began soon after Beijing and Moscow ended their Cold War confrontation, these exercises have become much more important during the last decade, essentially becoming a core pillar of their expanding defense partnership. China and Russia now conduct more naval exercises in more places and with more types of weapons systems than ever before. In the future, Chinese and Russian maritime drills will likely encompass new locations, capabilities, and partners-including possibly the Arctic, hypersonic delivery systems, and novel African, Asian, and Middle East partners-as well as continue such recent innovations as conducting joint naval patrols and combined arms maritime drills. China and Russia pursue several objectives through their bilateral naval cooperation. The Treaty of Good-Neighborliness and Friendly Cooperation Between the People's Republic of China and the Russian Federation lacks a mutual defense clause, but does provide for consultations about common threats. The naval exercises, which rehearse non-traditional along with traditional missions (e.g., counter-piracy and humanitarian relief as well as with high-end warfighting), provide a means to enhance their response to such mutual challenges through coordinated military activities. Though the exercises may not realize substantial interoperability gains regarding combat capabilities, the drills do highlight to foreign audiences the Sino-Russian capacity to project coordinated naval power globally. This messaging is important given the reliance of China and Russia on the world's oceans for trade and the two countries' maritime territorial disputes with other countries. The exercises can also improve their national military capabilities as well as help them learn more about the tactics, techniques, and procedures of each other. The rising Chinese Navy especially benefits from working with the Russian armed forces, which have more experience conducting maritime missions, particularly in combat operations involving multiple combat arms, than the People's Liberation Army (PLA). On the negative side, these exercises, by enhancing their combat capabilities, may make Chinese and Russian policymakers more willing to employ military force or run escalatory risks in confrontations with other states. All these impacts are amplified in Northeast Asia, where the Chinese and Russian navies conduct most of their joint exercises. Northeast Asia has become an area of intensifying maritime confrontations involving China and Russia against the United States and Japan, with South Korea situated uneasily between them. The growing ties between the Chinese and Russian navies have complicated South Korean-U.S. military planning, diverted resources from concentrating against North Korea, and worsened the regional security environment. Naval planners in the United States, South Korea, and Japan will increasingly need to consider scenarios involving both the Chinese and Russian navies. For example, South Korean and U.S. policymakers need to prepare for situations in which coordinated Chinese and Russian military aggression overtaxes the Pentagon, obligating the South Korean Navy to rapidly backfill for any U.S.-allied security gaps that arise on the Korean Peninsula. Potentially reinforcing Chinese and Russian naval support to North Korea in a maritime confrontation with South Korea and its allies would present another serious challenge. Building on the commitment of Japan and South Korea to strengthen security ties, future exercises involving Japan, South Korea, and the United States should expand to consider these potential contingencies.

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A Study for Strategy of On-line Shopping Mall: Based on Customer Purchasing and Re-purchasing Pattern (시스템 다이내믹스 기법을 활용한 온라인 쇼핑몰의 전략에 관한 연구 : 소비자의 구매 및 재구매 행동을 중심으로)

  • Lee, Sang-Gun;Min, Suk-Ki;Kang, Min-Cheol
    • Asia pacific journal of information systems
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    • v.18 no.3
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    • pp.91-121
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    • 2008
  • Electronic commerce, commonly known as e-commerce or eCommerce, has become a major business trend in these days. The amount of trade conducted electronically has grown extraordinarily by developing the Internet technology. Most electronic commerce has being conducted between businesses to customers; therefore, the researches with respect to e-commerce are to find customer's needs, behaviors through statistical methods. However, the statistical researches, mostly based on a questionnaire, are the static researches, They can tell us the dynamic relationships between initial purchasing and repurchasing. Therefore, this study proposes dynamic research model for analyzing the cause of initial purchasing and repurchasing. This paper is based on the System-Dynamic theory, using the powerful simulation model with some restriction, The restrictions are based on the theory TAM(Technology Acceptance Model), PAM, and TPB(Theory of Planned Behavior). This article investigates not only the customer's purchasing and repurchasing behavior by passing of time but also the interactive effects to one another. This research model has six scenarios and three steps for analyzing customer behaviors. The first step is the research of purchasing situations. The second step is the research of repurchasing situations. Finally, the third step is to study the relationship between initial purchasing and repurchasing. The purpose of six scenarios is to find the customer's purchasing patterns according to the environmental changes. We set six variables in these scenarios by (1) changing the number of products; (2) changing the number of contents in on-line shopping malls; (3) having multimedia files or not in the shopping mall web sites; (4) grading on-line communities; (5) changing the qualities of products; (6) changing the customer's degree of confidence on products. First three variables are applied to study customer's purchasing behavior, and the other variables are applied to repurchasing behavior study. Through the simulation study, this paper presents some inter-relational result about customer purchasing behaviors, For example, Active community actions are not the increasing factor of purchasing but the increasing factor of word of mouth effect, Additionally. The higher products' quality, the more word of mouth effects increase. The number of products and contents on the web sites have same influence on people's buying behaviors. All simulation methods in this paper is not only display the result of each scenario but also find how to affect each other. Hence, electronic commerce firm can make more realistic marketing strategy about consumer behavior through this dynamic simulation research. Moreover, dynamic analysis method can predict the results which help the decision of marketing strategy by using the time-line graph. Consequently, this dynamic simulation analysis could be a useful research model to make firm's competitive advantage. However, this simulation model needs more further study. With respect to reality, this simulation model has some limitations. There are some missing factors which affect customer's buying behaviors in this model. The first missing factor is the customer's degree of recognition of brands. The second factor is the degree of customer satisfaction. The third factor is the power of word of mouth in the specific region. Generally, word of mouth affects significantly on a region's culture, even people's buying behaviors. The last missing factor is the user interface environment in the internet or other on-line shopping tools. In order to get more realistic result, these factors might be essential matters to make better research in the future studies.