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다변량 프로빗 모형을 이용한 가전제품 구매의 상관관계 분석 (Correlation among Ownership of Home Appliances Using Multivariate Probit Model)

  • 김창섭;신정우;이미숙;이종수
    • 마케팅과학연구
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    • 제19권2호
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    • pp.17-26
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    • 2009
  • As the lifestyle of consumers changes and the need for various products increases, new products are being developed in the market. Each household owns various home appliances which are purchased through the choice of a decision maker. These appliances include not only large-sized products such as TV, refrigerator, and washing machine, but also small-sized products such as microwave oven and air cleaner. There exists latent correlation among possession of home appliances, even though they are purchased independently. The purpose of this research is to analyze the effect of demographic factors on the purchase and possession of each home appliances, and to derive some relationships among various appliances. To achieve this purpose, the present status on the possession of each home appliances are investigated through consumer survey data on the electric and energy product. And a multivariate probit(MVP) model is applied for the empirical analysis. From the estimation results, some appliances show a substitutive or complementary pattern as expected, while others which look apparently unrelated have correlation by co-incidence. This research has several advantages compared to previous literatures on home appliances. First, this research focuses on the various products which are purchased by each household, while previous researches such as Matsukawa and Ito(1998) and Yoon(2007) focus just on a particular product. Second, the methodology of this research can consider a choice process of each product and correlation among products simultaneously. Lastly, this research can analyze not only a substitutive or complementary relationship in the same category, but also the correlation among products in the different categories. As the data on the possession of home appliances in each household has a characteristic of multiple choice, not a single choice, a MVP model are used for the empirical analysis. A MVP model is derived from a random utility model, and has an advantage compared to a multinomial logit model in that correlation among error terms can be derive(Manchanda et al., 1999; Edwards and Allenby, 2003). It is assumed that the error term has a normal distribution with zero mean and variance-covariance matrix ${\Omega}$. Hence, the sign and value of correlation coefficients means the relationship between two alternatives(Manchanda et al., 1999). This research uses the data of 'TEMEP Household ICT/Energy Survey (THIES) 2008' which is conducted by Technology Management, Economics and Policy Program in Seoul National University. The empirical analysis of this research is accomplished in two steps. First, a MVP model with demographic variables is estimated to analyze the effect of the characteristics of household on the purchase of each home appliances. In this research, some variables such as education level, region, size of family, average income, type of house are considered. Second, a MVP model excluding demographic variables is estimated to analyze the correlation among each home appliances. According to the estimation results of variance-covariance matrix, each households tend to own some appliances such as washing machine-refrigerator-cleaner-microwave oven, and air conditioner-dish washer-washing machine and so on. On the other hand, several products such as analog braun tube TV-digital braun tube TV and desktop PC-portable PC show a substitutive pattern. Lastly, the correlation map of home appliances are derived using multi-dimensional scaling(MDS) method based on the result of variance-covariance matrix. This research can provide significant implications for the firm's marketing strategies such as bundling, pricing, display and so on. In addition, this research can provide significant information for the development of convergence products and related technologies. A convergence product can decrease its market uncertainty, if two products which consumers tend to purchase together are integrated into it. The results of this research are more meaningful because it is based on the possession status of each household through the survey data.

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포텐셜 자료해석을 통한 화산칼데라 구조 해석 (Analysis of the Geological Structure of the Hwasan Caldera Using Potential Data)

  • 박계순;류희영;양준모;이희순;권병두;엄주영;김동오;박찬홍
    • 한국지구과학회지
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    • 제29권1호
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    • pp.1-12
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    • 2008
  • 본 연구에서는 한반도 남동부의 의성분지 내에 위치하는 화산칼데라 지역을 대상으로 지구물리학적 연구를 수행하였다. 기존 연구들의 한계를 극복하기 위해 원격탐사를 통한 전체적인 구조 특성을 분석한 후에 정밀한 3차원 포텐셜 해석을 수행하는 기법을 적용하였다. 첫 번째 단계로, 수치지질도 및 DEM 자료와 인공위성 영상을 이용하여 대상 지역의 선구조를 분석하였다. 선구조 분석 결과는 선행 연구결과와 상당히 잘 부합되었고, 남-북 방향과 남동-북서방향이 가장 우세함을 보여주었다. 두 번째 단계로, 선구조 분석 결과를 고려하여 의성분지 전체 지역에서 조밀한 중력탐사 자료를 획득하였고 항공자력탐사 자료와의 복합 해석을 통해 광역적인 칼데라의 구조를 조사하였다. 파워 스펙트럼 기법을 이용한 분석 결과, 의성 분지 하부는 개략적으로 2개의 밀도 불연속면 이 존재하는 것으로 해석되었다. 첫 번째 불연속면의 심도는 약 1 km로 칼데라 지역 내에 존재하는 화산쇄설성 퇴적암의 심도나 화산칼데라의 ring vent 위치에서 관입하고 있는 관입암의 심도로 판단되며, 두 번째 심도는 약 3-5 km로 분지기반암의 심도와 관련 있는 것으로 추정된다. 또한 3차원 중력역산을 실시한 결과 남서쪽의 백악기 팔공산 화강암과 북동쪽의 불국사 관입암류에 의한 저밀도체가 나타나고, 화산칼데라 중앙부 부근에는 화산쇄설성 퇴적암류 또는 칼데라 형성 과정에서 침강된 상부의 퇴적층으로 해석된 퇴적층이 주변보다 낮은 밀도를 가지며 하부로 약 1.5 km까지 연장되어 있는 것으로 분석되었다. 그러나 포텐셜 자료는 그 특성상 수직 분해능이 양호하지 못하므로, 수직적인 발달 특성을 갖는 칼데라의 구조를 정확히 파악하기는 어렵다. 본 연구에서는 이런 한계점을 극복하기 위해서 동일 지역에서 이루어졌던 자기지전류 탐사 결과와 비교 분석하여 효과적인 해석을 수행하였다.

임플란트 식립 초기 의원성 동요가 최종 골결합에 미치는 영향 (The influence of iatrogenic mobilization in the initial stage of implant installation on final osteointegration)

  • 곽명배;조진현;이두형;이청희
    • 대한치과보철학회지
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    • 제52권2호
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    • pp.105-112
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    • 2014
  • 연구 목적: 이 연구의 목적은 임플란트 식립 초기 수회의 의원성 동요가 최종 골결합에 미치는 영향을 확인하는 것이다. 연구 재료 및 방법: 순수한 티타늄(Grade IV) 으로 직경 3.75 mm, 길이 8 mm의 실험용 임플란트를 제작한 후, 하방 4 mm에 RBM 표면처리($MegaGen^{(R)}$: Ca-P)를 하였다. 임플란트의 하부만 골에 식립되었으며 비침하시켰다. 수술은 3.5 kg이상의 토끼의 좌우 경골의 단층 치밀골에 각각 2개씩 130개를 통상적인 방법으로 식립하였다(Female, New Zealand White). 비틀림 제거 간격에 따라, 다음과 같은 13개의 군으로 나누었다; Group I (1일), Group II (1일 + 2일), Group III (1일 + 2일 + 3일), Group IV (1일 + 2일 + 3일 + 4일), Group V (2일), Group VI (2일 + 4일), Group VII (2일 + 4일 + 6일), Group VIII (2일 + 4일 + 6일 + 8일), Group IX (4일), Group X (4일 + 7일), Group XI (4일 + 7일 + 10일), Group XII (4일 + 7일 + 10일 + 14일), 그리고 대조군. 대조군은 식립 후 8주의 치유기간을 준 후 최종 비틀림 제거력을 측정하였다(Mark-10, USA). 실험군은 각각의 조건에 맞추어 1회에서 4회에 걸쳐 비틀림 제거력을 측정하였다. 비틀림 제거력을 측정한 이후에 대체적으로 임플란트를 측정 전의 위치로 재위치시켰다. 모든 실험군에서 임플란트 식립 후 8주간의 치유기간을 준 다음 최종 비틀림 제거력을 측정하여 대조군, 각 실험군의 1, 2, 3, 4번째 비틀림 제거력과 비교하였다. 결과: 실험군 간에 최종 비틀림 제거력을 비교한 결과에서, XII군을 제외한 실험군의 비틀림 제거력은 대조군과 유의할만한 차이를 보이지는 않았다. 그리고 실험 I군과 II군의 값은 VI, VIII, X, XI, XII군의 값보다 유의하게 높게 나타났다. 그리고 III, IV, V군은 XI, XII군의 값보다 유의하게 높게 나타났다. 각 실험군간 비틀림 제거력 비교에서, 최종 비틀림 제거력은 VIII, X, XI, XII군을 제외한 모든 군에서 높게 나타났다. 결론: 충분한 치유기간이 주어진다면, 토끼에게 임플란트 식립 후 매우 이른 초기에 지대주에 가해지는 약간의 동요는 임플란트 골결합에 영향을 미치지 않았다.

ARCUSdigma 2와 Checkbite를 사용하여 측정한 과로경사각 비교 (Comparison of condylar guidance using ARCUSdigma 2 and Checkbite)

  • 이동인;이창희;손미경;정재헌;강동완
    • 대한치과보철학회지
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    • 제51권3호
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    • pp.153-159
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    • 2013
  • 연구 목적: 근래에 들어 체크바이트 법뿐만 아니라 디지털 센서를 이용하여 하악의 운동을 기록, 분석하여 과로각을 계산하는 방법이 개발되어 사용되어져 오고 있으나 두 방법간의 비교하는 연구는 없었다. 이에 새로운 방법인 ARCUSdigma 2 system을 이용한 방법과 전통적인 방법인 체크바이트 법으로 과로각을 측정하여 두 방법 간의 차이를 비교해 보고자 하였다. 연구 대상 및 방법: 교정치료의 경험이 없고, 제3대구치를 제외한 치아의 결손이 없고, 교합평면의 변화를 수반한 광범위한 수복이 없으며, 악관절 질환이 없는 24세부터 34세 사이의 건강한 젊은 성인 남녀(남 10명, 여 10명)를 대상으로 하여 Camper's plane을 기준으로 하여 ARCUSdigma 2 system과 왁스를 사용한 체크바이트법을 각각 3번씩 측정하였으며 교합기는 KaVo Protar Evo 7 반조절성 교합기를 사용하여 각각의 방법으로 과로경사각을 측정하였다. 두 방법 간의 자료를 SPSS 20을 이용한 Mann-Whitney U Test를 사용하여 통계적으로 분석하였다. 결과: 1. ARCUSdigma 2 system에서 전방시상과로각은 좌우 각각 $26.97^{\circ}({\pm}7.38^{\circ})$, $29.80^{\circ}({\pm}8.19^{\circ})$로 측정되었으며, 측방과로경사각은 $5.75^{\circ}({\pm}3.47^{\circ})$$8.10^{\circ}({\pm}4.98^{\circ})$로 측정되었다. 2. 체크바이트법에서 전방시상과로각은 좌우 각각 $25.20^{\circ}({\pm}6.53^{\circ})$, $28.18^{\circ}({\pm}7.38^{\circ})$로 측정되었으며, 측방과로경사각은 $10.97^{\circ}({\pm}5.63^{\circ})$$12.03^{\circ}({\pm}5.22^{\circ})$로 측정되었다. 결론:두 방법 모두 남녀간 좌우간 유의적 차이는 나타나지 않았으며 두 방법 사이에서는 측방시상과로각에서 ARCUSdigma 2를 사용하여 측정한 값이 Checkbite를 사용하여 측정한 값보다 통계적으로 유의하게 작게 측정되었다(P<.05).

광중합기에 따른 복합레진 중합시 온도 변화와 미세경도에 관한 연구 (THERMAL CHANGE AND MICROHARDNESS IN CURING COMPOSITE RESIN ACCORDING TO VARIOUS CURING LIGHT SYSTEM)

  • 이동진;김대업;양영숙;이광희
    • 대한소아치과학회지
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    • 제31권3호
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    • pp.391-399
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    • 2004
  • 현재 복합레진의 중합에 사용되는 광원으로 할로겐광 중합기, 플라즈마 아크 중합기, 레이저, LED 등이 사용되고 있으나 광조사에 따른 온도 증가와 중합 깊이 등이 수복치과학의 오랜 관심이었다. 본 연구의 목적은 광원에 따라 얼마나 온도 증가가 일어나는지, 그리고 중합 깊이에 따른 표면경도를 측정함으로써 전통적인 할로겐광 중합기에 대해 새로 개발된 중합기의 중합능력을 비교 평가하는 것이다. 기존의 할로겐광 중합기(Optilux 360)에 대해 최근 시판되는 플라즈마 아크 중합기(Flipo), 열 발생을 감소시킨 플라즈마 아크 중합기(Aurys), LED(Starlight), 그리고 중합시간을 감소시킨 고강도 LED(Freelight 2) 등을 광원으로 사용하였다. 우선 상온$(23^{\circ}C)$에서 각 중합기 표면의 온도를 측정한 후 각각 2, 3, 4mm의 테플론 mold에 레진(Z-100, $A_2\;Shade$)을 충전하고 하면에서 중합시 최고 온도를 측정하였으며 각 시편 상, 하면의 미세경도를 측정하여 다음과 같은 결론을 얻었다. 1. 중합기 표면의 온도를 측정한 결과 Flipo가 평균 $52.4^{\circ}C$로 가장 높았고 Freelight $2(37.86^{\circ}C),\;Optilux\;360(32.68^{\circ}C),\;Aurys(32.34^{\circ}C),\;Starlight(26.14^{\circ}C)$ 순으로 낮게 나타났다. 2. 복합레진을 2, 3, 4mm 테플론 mold에 채우고 중합시 온도 변화를 측정한 결과 Flipo와 Freelight 2가 유사하게 가장 높았고 Optilux 360과 Aurys가 유사하게 그 다음이었으며 Starlight가 가장 낮게 나타났다. 3. 복합레진 상면의 미세경도는 전반적으로 유사하였으나 Aurys로 중합한 군에서 약간 낮게 측정되었다. 4. 복합레진 하면의 미세경도는 2, 3, 4mm모두에서 Optilux 360과 Freelight 2로 중합한 군에서 유사하게 가장 높았고 그 다음이 Flipo, Starlight 순이었으며 Aurys로 중합한 군에서 가장 낮게 측정되었다. 연구 결과에서 볼 때 Flipo와 Freelight 2를 주의깊게 사용한다면 중합도와 시간면에서 임상적으로 유용하게 사용될 수 있으리라 사료된다.

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인터넷 커뮤니티에서 사용자 참여가 밀착도와 지속적 이용의도에 미치는 영향 (A Study on the Effects of User Participation on Stickiness and Continued Use on Internet Community)

  • 고미현;권순동
    • Asia pacific journal of information systems
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    • 제18권2호
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    • pp.41-72
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    • 2008
  • The purpose of this study is the investigation of the effects of user participation, network effect, social influence, and usefulness on stickiness and continued use on Internet communities. In this research, stickiness refers to repeat visit and visit duration to an Internet community. Continued use means the willingness to continue to use an Internet community in the future. Internet community-based companies can earn money through selling the digital contents such as game, music, and avatar, advertizing on internet site, or offering an affiliate marketing. For such money making, stickiness and continued use of Internet users is much more important than the number of Internet users. We tried to answer following three questions. Fist, what is the effects of user participation on stickiness and continued use on Internet communities? Second, by what is user participation formed? Third, are network effect, social influence, and usefulness that was significant at prior research about technology acceptance model(TAM) still significant on internet communities? In this study, user participation, network effect, social influence, and usefulness are independent variables, stickiness is mediating variable, and continued use is dependent variable. Among independent variables, we are focused on user participation. User participation means that Internet user participates in the development of Internet community site (called mini-hompy or blog in Korea). User participation was studied from 1970 to 1997 at the research area of information system. But since 1997 when Internet started to spread to the public, user participation has hardly been studied. Given the importance of user participation at the success of Internet-based companies, it is very meaningful to study the research topic of user participation. To test the proposed model, we used a data set generated from the survey. The survey instrument was designed on the basis of a comprehensive literature review and interviews of experts, and was refined through several rounds of pretests, revisions, and pilot tests. The respondents of survey were the undergraduates and the graduate students who mainly used Internet communities. Data analysis was conducted using 217 respondents(response rate, 97.7 percent). We used structural equation modeling(SEM) implemented in partial least square(PLS). We chose PLS for two reason. First, our model has formative constructs. PLS uses components-based algorithm and can estimated formative constructs. Second, PLS is more appropriate when the research model is in an early stage of development. A review of the literature suggests that empirical tests of user participation is still sparse. The test of model was executed in the order of three research questions. First user participation had the direct effects on stickiness(${\beta}$=0.150, p<0.01) and continued use (${\beta}$=0.119, p<0.05). And user participation, as a partial mediation model, had a indirect effect on continued use mediated through stickiness (${\beta}$=0.007, p<0.05). Second, optional participation and prosuming participation significantly formed user participation. Optional participation, with a path magnitude as high as 0.986 (p<0.001), is a key determinant for the strength of user participation. Third, Network effect (${\beta}$=0.236, p<0.001). social influence (${\beta}$=0.135, p<0.05), and usefulness (${\beta}$=0.343, p<0.001) had directly significant impacts on stickiness. But network effect and social influence, as a full mediation model, had both indirectly significant impacts on continued use mediated through stickiness (${\beta}$=0.11, p<0.001, and ${\beta}$=0.063, p<0.05, respectively). Compared with this result, usefulness, as a partial mediation model, had a direct impact on continued use and a indirect impact on continued use mediated through stickiness. This study has three contributions. First this is the first empirical study showing that user participation is the significant driver of continued use. The researchers of information system have hardly studies user participation since late 1990s. And the researchers of marketing have studied a few lately. Second, this study enhanced the understanding of user participation. Up to recently, user participation has been studied from the bipolar viewpoint of participation v.s non-participation. Also, even the study on participation has been studied from the point of limited optional participation. But, this study proved the existence of prosuming participation to design and produce products or services, besides optional participation. And this study empirically proved that optional participation and prosuming participation were the key determinant for user participation. Third, our study compliments traditional studies of TAM. According prior literature about of TAM, the constructs of network effect, social influence, and usefulness had effects on the technology adoption. This study proved that these constructs still are significant on Internet communities.

업무성과에 영향을 주는 업무용 모바일 어플리케이션의 주요 요인에 관한 연구 (An Empirical Study on the Influencing Factors of Perceived Job Performance in the Context of Enterprise Mobile Applications)

  • 정성훈;김기민
    • Asia pacific journal of information systems
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    • 제24권1호
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    • pp.31-50
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    • 2014
  • The ubiquitous accessibility of information through mobile devices has led to an increased mobility of workers from their fixed workplaces. Market researchers estimate that by 2016, 350 million workers will be using their smartphones for business purposes, and the use of smartphones will offer new business benefits. Enterprises are now adopting mobile technologies for numerous applications to increase their operational efficiency, improve their responsiveness and competitiveness, and cultivate their innovativeness. For these reasons, various organizational aspects concerning "mobile work" have received a great deal of recent attention. Moreover, many CIOs plan to allocate a considerable amount of their budgets mobile work environments. In particular, with the consumerization of information technology, enterprise mobile applications (EMA) have played a significant role in the explosive growth of mobile computing in the workplace, and even in improving sales for firms in this field. EMA can be defined as mobile technologies and role-based applications, as companies design them for specific roles and functions in organizations. Technically, EMA can be defined as business enterprise systems, including critical business functions that enable users to access enterprise systems via wireless mobile devices, such as smartphones or tablets. Specifically, EMA enables employees to have greater access to real-time information, and provides them with simple features and functionalities that are easy for them to complete specific tasks. While the impact of EMA on organizational workers' productivity has been given considerable attention in various literatures, relatively little research effort has been made to examine how EMA actually lead to users' job performance. In particular, we have a limited understanding of what the key antecedents are of such an EMA usage outcome. In this paper, we focus on employees' perceived job performance as the outcome of EMA use, which indicates the successful role of EMA with regard to employees' tasks. Thus, to develop a deeper understanding of the relationship among EMA, its environment, and employees' perceived job performance, we develop a comprehensive model that considers the perceived-fit between EMA and employees' tasks, satisfaction on EMA, and the organizational environment. With this model, we try to examine EMA to explain how job performance through EMA is revealed from both the task-technology fit for EMA and satisfaction on EMA, while also considering the antecedent factors for these constructs. The objectives of this study are to address the following research questions: (1) How can employees successfully manage EMA in order to enhance their perceived job performance? (2) What internal and/or external factors are important antecedents in increasing EMA users' satisfaction on MES and task-technology fit for EMA? (3) What are the impacts of organizational (e.g. organizational agility), and task-related antecedents (e.g., task mobility) on task-technology fit for EMA? (4) What are the impacts of internal (e.g., self-efficacy) and external antecedents (e.g., system reputation) for the habitual use of EMA? Based on a survey from 254 actual employees who use EMA in their workplace across industries, our results indicate that task-technology fit for EMA and satisfaction on EMA are positively associated with job performance. We also identify task mobility, organizational agility, and system accessibility that are found to be positively associated with task-technology fit for EMA. Further, we find that external factor, such as the reputation of EMA, and internal factor, such as self-efficacy for EMA that are found to be positively associated with the satisfaction of EMA. The present findings enable researchers and practitioners to understand the role of EMA, which facilitates organizational workers' efficient work processes, as well as the importance of task-technology fit for EMA. Our model provides a new set of antecedents and consequence variables for a TAM involving mobile applications. The research model also provides empirical evidence that EMA are important mobile services that positively influence individuals' performance. Our findings suggest that perceived organizational agility and task mobility do have a significant influence on task-technology fit for EMA usage through positive beliefs about EMA, that self-efficacy and system reputation can also influence individuals' satisfaction on EMA, and that these factors are important contingent factors for the impact of system satisfaction and perceived job performance. Our findings can help managers gauge the impact of EMA in terms of its contribution to job performance. Our results provide an explanation as to why many firms have recently adopted EMA for efficient business processes and productivity support. Our findings additionally suggest that the cognitive fit between task and technology can be an important requirement for the productivity support of EMA. Further, our study findings can help managers in formulating their strategies and building organizational culture that can affect employees perceived job performance. Managers, thus, can tailor their dependence on EMA as high or low, depending on their task's characteristics, to maximize the job performance in the workplace. Overall, this study strengthens our knowledge regarding the impact of mobile applications in organizational contexts, technology acceptance and the role of task characteristics. To conclude, we hope that our research inspires future studies exploring digital productivity in the workplace and/or taking the role of EMA into account for employee job performance.

방사선 종양학과에서 CR System을 이용한 PACS 유용성 평가 (Using CR System at the Department of Radiation Oncology PACS Evaluation)

  • 홍성일;김영재
    • 한국방사선학회논문지
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    • 제6권2호
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    • pp.143-149
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    • 2012
  • 오늘날 의료영상매체의 획기적인 발전으로 각 병원에서 최신 의료장비를 도입함으로써 첨단화, 디지털화로 급변하는 추세이다. 이러한 움직임에 발맞추어 방사선 종양학과에서도 CR system을 도입하여 film system의 단점을 보완하고 병원에서 사용하고 있는 Picture Archiving and Communication System(PACS)과 Electronic Medical Record (EMR) , 그리고 Radiation therapy Treatment Planning system(RTP)의 network를 원활히 하여 업무효율 증대 및 환자에 대한 의료의 질 개선과 서비스 향상을 이루고자 하고 있는데, 방사선 종양학과의 Computed Radiography system(CR system)을 이용하여 PACS에 통합한 사례를 소개하고 그 유용성을 평가하고자 한다. 의료용 선형가속기인 MEVATRON-MX를 이용하여 현재 시행하고 있는 정도관리 중 Gantry, Collimator Star Shot, Light vs. Radiation Field Accuracy, HDR QA(Dwell position accuracy)를 시행하여 PACS 상에 구현하였고 모니터 상에서 디지털 영상을 통한 QA가 가능한지 확인하였다. 또한, 현재 S병원에서 사용 중인 Operation Control System(OCS)과 연동하여 치료에 필요한 코드를 각각의 치료에 부과하여 네트워크로 연결, CR상에 입력한 order가 나타나도록 하였으며, Planning System인 Pinacle과 PACS상의 지원 data 오류를 해결하여 PACS 상에서도 Planning 영상을 볼 수 있도록 하였다. CR system을 이용하여 L-gram, simulation image, planning image를 병원 내 어느 곳에서나 영상을 조회하고 볼 수 있게 PACS에 통합 구축되어있다. Filmless 환경에서 Dosimetry용 IP를 이용하여 Light/Radition field size 일치, gantry rotation axis의 정확성, collimator rotation axis의 정확성, brachy therapy의 Dwell position check등 QA의 시행이 가능하였다. CR system을 이용하여 방사선 종양학과에서 얻어지는 영상을 PACS에 통합함으로써 작업시간 단축과 그에 따른 불필요한 인력소모의 감소 등으로 인하여 업무효율이 증대되었지만 향후 환자정보에 대한 보안을 필요로 한다.

시맨틱 웹 기술혁신의 채택과 확산: 질적연구접근법 (The Adoption and Diffusion of Semantic Web Technology Innovation: Qualitative Research Approach)

  • 주재훈
    • Asia pacific journal of information systems
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    • 제19권1호
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    • pp.33-62
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    • 2009
  • Internet computing is a disruptive IT innovation. Semantic Web can be considered as an IT innovation because the Semantic Web technology possesses the potential to reduce information overload and enable semantic integration, using capabilities such as semantics and machine-processability. How should organizations adopt the Semantic Web? What factors affect the adoption and diffusion of Semantic Web innovation? Most studies on adoption and diffusion of innovation use empirical analysis as a quantitative research methodology in the post-implementation stage. There is criticism that the positivist requiring theoretical rigor can sacrifice relevance to practice. Rapid advances in technology require studies relevant to practice. In particular, it is realistically impossible to conduct quantitative approach for factors affecting adoption of the Semantic Web because the Semantic Web is in its infancy. However, in an early stage of introduction of the Semantic Web, it is necessary to give a model and some guidelines and for adoption and diffusion of the technology innovation to practitioners and researchers. Thus, the purpose of this study is to present a model of adoption and diffusion of the Semantic Web and to offer propositions as guidelines for successful adoption through a qualitative research method including multiple case studies and in-depth interviews. The researcher conducted interviews with 15 people based on face-to face and 2 interviews by telephone and e-mail to collect data to saturate the categories. Nine interviews including 2 telephone interviews were from nine user organizations adopting the technology innovation and the others were from three supply organizations. Semi-structured interviews were used to collect data. The interviews were recorded on digital voice recorder memory and subsequently transcribed verbatim. 196 pages of transcripts were obtained from about 12 hours interviews. Triangulation of evidence was achieved by examining each organization website and various documents, such as brochures and white papers. The researcher read the transcripts several times and underlined core words, phrases, or sentences. Then, data analysis used the procedure of open coding, in which the researcher forms initial categories of information about the phenomenon being studied by segmenting information. QSR NVivo version 8.0 was used to categorize sentences including similar concepts. 47 categories derived from interview data were grouped into 21 categories from which six factors were named. Five factors affecting adoption of the Semantic Web were identified. The first factor is demand pull including requirements for improving search and integration services of the existing systems and for creating new services. Second, environmental conduciveness, reference models, uncertainty, technology maturity, potential business value, government sponsorship programs, promising prospects for technology demand, complexity and trialability affect the adoption of the Semantic Web from the perspective of technology push. Third, absorptive capacity is an important role of the adoption. Fourth, suppler's competence includes communication with and training for users, and absorptive capacity of supply organization. Fifth, over-expectance which results in the gap between user's expectation level and perceived benefits has a negative impact on the adoption of the Semantic Web. Finally, the factor including critical mass of ontology, budget. visible effects is identified as a determinant affecting routinization and infusion. The researcher suggested a model of adoption and diffusion of the Semantic Web, representing relationships between six factors and adoption/diffusion as dependent variables. Six propositions are derived from the adoption/diffusion model to offer some guidelines to practitioners and a research model to further studies. Proposition 1 : Demand pull has an influence on the adoption of the Semantic Web. Proposition 1-1 : The stronger the degree of requirements for improving existing services, the more successfully the Semantic Web is adopted. Proposition 1-2 : The stronger the degree of requirements for new services, the more successfully the Semantic Web is adopted. Proposition 2 : Technology push has an influence on the adoption of the Semantic Web. Proposition 2-1 : From the perceptive of user organizations, the technology push forces such as environmental conduciveness, reference models, potential business value, and government sponsorship programs have a positive impact on the adoption of the Semantic Web while uncertainty and lower technology maturity have a negative impact on its adoption. Proposition 2-2 : From the perceptive of suppliers, the technology push forces such as environmental conduciveness, reference models, potential business value, government sponsorship programs, and promising prospects for technology demand have a positive impact on the adoption of the Semantic Web while uncertainty, lower technology maturity, complexity and lower trialability have a negative impact on its adoption. Proposition 3 : The absorptive capacities such as organizational formal support systems, officer's or manager's competency analyzing technology characteristics, their passion or willingness, and top management support are positively associated with successful adoption of the Semantic Web innovation from the perceptive of user organizations. Proposition 4 : Supplier's competence has a positive impact on the absorptive capacities of user organizations and technology push forces. Proposition 5 : The greater the gap of expectation between users and suppliers, the later the Semantic Web is adopted. Proposition 6 : The post-adoption activities such as budget allocation, reaching critical mass, and sharing ontology to offer sustainable services are positively associated with successful routinization and infusion of the Semantic Web innovation from the perceptive of user organizations.

지능 저하를 동반한 두부외상 환자에서 뇌혈류 및 혈류예비능의 변화 (Alterations of Cerebral Blood Flow and Cerebrovascular Reserve in Patients with Chronic Traumatic Brain Injury Accompanying Deteriorated Intelligence)

  • 송호천;범희승
    • 대한핵의학회지
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    • 제34권3호
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    • pp.183-198
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    • 2000
  • 목적: 두부외상을 받은 후 뇌실질의 해부학적인 병변이 없음에도 불구하고 인지 및 정신운동성 기능장애 등을 호소하는 환자가 많지만 아직 그 병태 생리가 밝혀지지 않고 있다. 연구자는 두부외상 후 해부학적 뇌 병변이 없으면서도 지능저하를 보인 환자에서 국소 뇌혈류(regional cerebral blood flow, CBF) 및 국소 혈류예비능(regional cerebrovascular reserve, CVR) 이상이 있는 지를 알아보고, 지능저하와 관련된 뇌영역을 분석하고자 하였다. 대상 및 방법: 두부외상을 받은 후 지능저하를 호소하고, 만성기에 시행한 뇌 MRI에서 유의한 대뇌피질의 이상소견이 없었던 30명으로 남자 16명과 여자 14명이었으며, 평균연령은 $34{\pm}12$세였다. 대조군을 19명으로 남자 9명과 여자 10명이었으며, 평균연령은 $44{\pm}17$세였다. 휴식기에 Tc-99m HMPAO 925 MHq를 주사하고 5분째 뇌혈류 SPECT를 촬영하였으며, 촬영 도중 아세타졸아미드 1 g을 3분간 주사하였다. 첫 촬영이 끝난 직후 다시 Tc-99m HMPAO 925 MBq를 주사하여 같은 방법으로 뇌부위를 촬영하였다. 지능검사는 한국판-웩슬러 성인용 지능검사(K-WAIS)를 사용하여 언어성과 동작성에 관련된 11가지 소검사를 시행하였다. 각 소검사 별 비정상 점수를 보인 환자군과 정상 대조군간 유의한 CBF 차이를 윈도우용 SPM'97로 비교분석하여 다음과 같은 결과를 얻었다. 결과: 1) 모든 언어성 소검사는 좌측 대뇌반구에서 CBF 감소를 보였고, Wernicke 영역과 모두 관련이 있었고 Broca 영역과 관련을 보인 어휘문제를 포함하여 기본지식문제와 숫자외우기는 전두엽, 측두엽 그리고 두정엽과도 관련이 있었다. 우측 대뇌반구에 추가로 CBF 감소를 보인 경우는 기본지식문제, 숫자외우기, 어휘문제와 공통성문제로 전두엽, 측두엽 그리고 두정엽에서 CBF가 감소를 보였다. 2) 동작성 검사에서 CBF 감소는 주로 우측 대뇌반구에서 관찰되었다. 우측 상측두회 후면과 상연회, 운동전 피질, 그리고 일차적 체운동피질과, 우측 전두전야 일부에서 관련이 있었고, 좌측 전두엽과 상연회 일부에서 CBF 감소가 있었다. 3) CVR 감소는 전체적으로 총 64개 뇌영역에서 관찰되었다. 언어성 검사에서 주로 양측 전두엽과 측두엽에서 관찰되었다. 기본지식문제만 양측 하두정회와 후두엽에서 추가로 CVR 감소가 관찰되었다. 동작성 검사에서 주로 양측 전두전야와 상, 중측두회와 관련이 있었다. 결론: 두부외상 후 대뇌피질의 형태학적 손상을 발견할 수 없었던 경미한 손상에서도 CBF 뿐만 아니라 CVR의 감소를 초래되며, 지능 저하와 관련이 있음을 알 수 있었다. 이러한 지능 저하는 특정한 뇌영역과 관련되어 있음을 밝혔다.

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