• 천문학회보
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• 제39권2호
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• pp.90-90
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• 2014

The Immersion Grating Infrared Spectrometer (IGRINS) is the first astronomical spectrograph that uses a silicon immersion grating as its dispersive element. IGRINS fully covers the H and K band atmospheric transmission windows in a single exposure. It is a compact high-resolution cross-dispersion spectrometer whose resolving power R is 40,000. An individual volume phase holographic grating serves as a secondary dispersing element for each of the H and K spectrograph arms. On the 2.7m Harlan J. Smith telescope at the McDonald Observatory, the slit size is $1^{{\prime}{\prime}}{\times}15^{{\prime}{\prime}}$. IGRINS has a plate scale of 0.27" pixel-1 on a $2048{\times}2048$ pixel Teledyne Scientific & Imaging HAWAII-2RG detector with a SIDECAR ASIC cryogenic controller. The instrument includes four subsystems; a calibration unit, an input relay optics module, a slit-viewing camera, and nearly identical H and K spectrograph modules. The use of a silicon immersion grating and a compact white pupil design allows the spectrograph collimated beam size to be 25mm, which permits the entire cryogenic system to be contained in a moderately sized ($0.96m{\times}0.6m{\times}0.38m$) rectangular Dewar. The fabrication and assembly of the optical and mechanical components were completed in 2013. From January to July of this year, we completed the system optical alignment and carried out commissioning observations on three runs to improve the efficiency of the instrument software and hardware. We describe the major design characteristics of the instrument including the system requirements and the technical strategy to meet them. We also present the instrumental performance test results derived from the commissioning runs at the McDonald Observatory.

• 대한치과보철학회지
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• 제51권3호
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• pp.147-152
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• 2013

연구 목적: 이 연구는 정상배열을 가지고 있는 한국 유치악 성인에서 얼굴형과 성별에 따라 절치유두를 기준으로 한 상악전치의 위치와 견치폭경 계측치를 제시한다. 연구 대상 및 방법: 전남대학교 치의학 전문대학원에 다니는 학생 중 crowding 및 spacing이 없으며, Angles Class I의 정상 교합관계를 가지고 있는 42명을 대상으로 조사하였다. 선정된 학생들의 두부 측면 방사선 사진을 찍고, posterior facial height (PFH)과 anterior facial height (AFH)을 측정하여 PFH / AFH%를 구하여 cephalic type을 나누었다. 그 후 42명의 상악 모형을 준비하여 버니어캘리퍼스로 상악 중절치 절단연에서 절치 유두 중앙까지의 수평거리(A)와 상악 견치간 거리(B)를 계측, 평균값을 구하였으며, SPSS version 15를 사용하여 통계분석 및 유의성을 검토하였다. 결과: Dolichocephalic type을지닌10명에서A의 평균값은 $8.43{\pm}0.61$, B의 평균값은 $36.73{\pm}2.17$으로 나타났다. Mesocephalic type과 brachycephalic type의경우각각A의평균값은 $8.51{\pm}1.27$, $8.76{\pm}1.03$, B의 평균값은 $35.91{\pm}1.86$, $37.34 {\pm}2.23$로 나타났다. 성별에 따른 계측 결과 남성에서A의 평균값은 $8.86{\pm}1.04$, B의 평균값은 $37.60{\pm}0.24$으로 나타났으며, 여성에서A의 평균값은 $8.41{\pm}0.93$, B의 평균값은 $36.18{\pm}2.01$로 나타났다. A값의 경우 남성이 여성보다 큰 값을 보였으나 그 차이는 통계적으로 유의하지 않았다(P>.05). B값의 경우 남성이 여성보다 큰 값을 보였으며, 통계적으로 유의성을 나타내었다 (P<.05). 결론:한국에서 정상 치열 및 교합을 가진 평균 연령 30세, 42명의 학생을 대상으로 조사하였을 때, 절치유두에서 상악 중절치 절단연까지의 수평 거리는 cephalic type이나 성별에 따른 차이가 없었고, 견치 교두정간 거리는 cephalic type에 따른 차이가 없었지만, 성별에 따라 유의한 차이를 보였으며 남성이 여성보다 큰 값을 나타냈다.

• Asia pacific journal of information systems
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• 제19권3호
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• pp.99-124
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• 2009

Many firms in Korea have adopted and used advanced information technology in an effort to boost efficiency. The process of adapting to the new technology, at the same time, can vary from one firm to another. As such, this research focuses on several relevant factors, especially the roles of social interaction as a key variable that influences the technology adaptation process and the outcomes. Thus far, how a firm goes through the adaptation process to the new technology has not been yet fully explored. Previous studies on changes undergone by a firm or an organization due to information technology have been pursued from various theoretical points of views, evolved from technological and institutional views to an integrated social technology views. The technology adaptation process has been understood to be something that evolves over time and has been regarded as cycles between misalignments and alignments, gradually approaching the stable aligned state. The adaptation process of the new technology was defined as "appropriation" process according to Poole and DeSanctis (1994). They suggested that this process is not automatically determined by the technology design itself. Rather, people actively select how technology structures should be used; accordingly, adoption practices vary. But concepts of the appropriation process in these studies are not accurate while suggested propositions are not clear enough to apply in practice. Furthermore, these studies do not substantially suggest which factors are changed during the appropriation process and what should be done to bring about effective outcomes. Therefore, research objectives of this study lie in finding causes for the difference in ways in which advanced information technology has been used and adopted among organizations. The study also aims to explore how a firm's interaction with social as well as technological factors affects differently in resulting organizational changes. Detail objectives of this study are as follows. First, this paper primarily focuses on the appropriation process of advanced information technology in the long run, and we look into reasons for the diverse types of the usage. Second, this study is to categorize each phases in the appropriation process and make clear what changes occur and how they are evolved during each phase. Third, this study is to suggest the guidelines to determine which strategies are needed in an individual, group and organizational level. For this, a substantially grounded theory that can be applied to organizational practice has been developed from a longitudinal comparative case study. For these objectives, the technology appropriation process was explored based on Structuration Theory by Giddens (1984), Orlikoski and Robey (1991) and Adaptive Structuration Theory by Poole and DeSanctis (1994), which are examples of social technology views on organizational change by technology. Data have been obtained from interviews, observations of medical treatment task, and questionnaires administered to group members who use the technology. Data coding was executed in three steps following the grounded theory approach. First of all, concepts and categories were developed from interviews and observation data in open coding. Next, in axial coding, we related categories to subcategorize along the lines of their properties and dimensions through the paradigm model. Finally, the grounded theory about the appropriation process was developed through the conditional/consequential matrix in selective coding. In this study eight hypotheses about the adaptation process have been clearly articulated. Also, we found that the appropriation process involves through three phases, namely, "direct appropriation," "cooperate with related structures," and "interpret and make judgments." The higher phases of appropriation move, the more users represent various types of instrumental use and attitude. Moreover, the previous structures like "knowledge and experience," "belief that other members know and accept the use of technology," "horizontal communication," and "embodiment of opinion collection process" are evolved to higher degrees in their dimensions of property. Furthermore, users continuously create new spirits and structures, while removing some of the previous ones at the same time. Thus, from longitudinal view, faithful and unfaithful appropriation methods appear recursively, but gradually faithful appropriation takes over the other. In other words, the concept of spirits and structures has been changed in the adaptation process over time for the purpose of alignment between the task and other structures. These findings call for a revised or extended model of structural adaptation in IS (Information Systems) literature now that the vague adaptation process in previous studies has been clarified through the in-depth qualitative study, identifying each phrase with accuracy. In addition, based on these results some guidelines can be set up to help determine which strategies are needed in an individual, group, and organizational level for the purpose of effective technology appropriation. In practice, managers can focus on the changes of spirits and elevation of the structural dimension to achieve effective technology use.

• 한국의학물리학회지:의학물리
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• 제26권4호
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• pp.215-222
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• 2015

본 연구에서는 단일 비산란 그리드 및 다색광 x-선원을 이용하여 위상대조 x-선 영상을 용이하게 구현할 수 있는 새로운 방법을 제안한다. 제안된 신기법의 개념 입증을 위해 집속형 선형 그리드(200 lines/inch 선 밀도), 마이크로 초점 x-선관(${\sim}5{\mu}m$ 초점크기), CMOS형 평판형 검출기($48{\mu}m$ 픽셀 크기)로 실험장치를 구성하였으며, 한 번의 x-선 촬영($90kV_p$, 0.1 mAs)으로 감약대조 x-선 영상과 향상된 가시성을 지진 산란 x-선 영상 및 차분 위상대조 x-선 영상을 Fourier변조복원 기법을 적용하여 성공적으로 분리 획득하였다. 더 나아가, 감약대조 x-선 영상과 산란 x-선 영상을 합성함으로써 일반 감약대조 x-선 영상에서는 명확하게 볼 수 없는 샘플의 미세 구조를 보다 선명하게 나타냄을 확인하였다. 본 논문에서 제안한 단일 비산란 그리드 기반 위상대조 x-선 영상화 기법은 실험 구성 및 절차가 단순하고 새로운 대조도에 기반한 산란 및 위상대조 x-선 영상을 동시에 제공하기 때문에 차세대 x-선 영상화 신기법으로 다양한 응용분야에서 용이하게 적용될 수 있을 것으로 전망한다.

• Asia pacific journal of information systems
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• 제20권3호
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• pp.191-204
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• 2010

Recently, the CO2 emission and energy consumption have become critical global issues to decide the future of nations. Especially, the spread of IT products and the increased use of internet and web applications result in the energy consumption and CO2 emission of IT industry though information technologies drive global economic growth. EU, the United States, Japan and other developed countries are using IT related environmental regulations such as WEEE(Waste Electrical and Electronic Equipment), RoHS(Restriction of the use of Certain Hazardous Substance), REACH(Registration, Evaluation, Authorization and Restriction of CHemicals) and EuP(Energy using Product), and have established systematic green business/IT strategies to enhance the competitiveness of IT industry. For example, the Japan government proposed the "Green IT initiative" for being compatible with economic growth and environmental protection. Not only energy saving technologies but energy saving systems have been developed for accomplishing sustainable development. Korea's CO2 emission and energy consumption continuously have grown at comparatively high rates. They are related to its industrial structure depending on high energy-consuming industries such as iron and steel Industry, automotive industry, shipbuilding industry, semiconductor industry, and so on. In particular, export proportion of IT manufacturing is quite high in Korea. For example, the global market share of the semiconductor such as DRAM was about 80% in 2008. Accordingly, Korea needs to establish a systematic strategy to respond to the global environmental regulations and to maintain competitiveness in the IT industry. However, green competitiveness of Korea ranked 11th among 15 major countries and R&D budget for green technology is not large enough to develop energy-saving technologies for infrastructure and value chain of low-carbon society though that grows at high rates. Moreover, there are no concrete action plans in Korea. This research aims to deduce the priorities of the Korean green business/IT strategies to use multi attribute weighted average method. We selected a panel of 19 experts who work at the green business related firms such as HP, IBM, Fujitsu and so on, and selected six assessment indices such as the urgency of the technology development, the technology gap between Korea and the developed countries, the effect of import substitution, the spillover effect of technology, the market growth, and the export potential of the package or stand-alone products by existing literature review. We submitted questionnaires at approximately weekly intervals to them for priorities of the green business/IT strategies. The strategies broadly classify as follows. The first strategy which consists of the green business/IT policy and standardization, process and performance management and IT industry and legislative alignment relates to government's role in the green economy. The second strategy relates to IT to support environment sustainability such as the travel and ways of working management, printer output and recycling, intelligent building, printer rationalization and collaboration and connectivity. The last strategy relates to green IT systems, services and usage such as the data center consolidation and energy management, hardware recycle decommission, server and storage virtualization, device power management, and service supplier management. All the questionnaires were assessed via a five-point Likert scale ranging from "very little" to "very large." Our findings show that the IT to support environment sustainability is prior to the other strategies. In detail, the green business /IT policy and standardization is the most important in the government's role. The strategies of intelligent building and the travel and ways of working management are prior to the others for supporting environment sustainability. Finally, the strategies for the data center consolidation and energy management and server and storage virtualization have the huge influence for green IT systems, services and usage This research results the following implications. The amount of energy consumption and CO2 emissions of IT equipment including electrical business equipment will need to be clearly indicated in order to manage the effect of green business/IT strategy. And it is necessary to develop tools that measure the performance of green business/IT by each step. Additionally, intelligent building could grow up in energy-saving, growth of low carbon and related industries together. It is necessary to expand the affect of virtualization though adjusting and controlling the relationship between the management teams.

• 한국패류학회지
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• 제25권2호
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• pp.153-160
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• 2009

Pisidium (Neopisidium) coreanum의 metallothionein 유전자는 염기서열 315개로 이루어져있으며 105개의 아미노산으로 이루어져 있었다. 연체동물의 metallothionein 서열의 공식[C-x-C-x(3)-C-T-G-x(3)-C-x-C-x(3)-C-x-C-K] 에 맞춰본 결과 알려진 공식과 상당히 일치하는 것을 확인할 수 있었으며 아미노산의 조성도 시스테인 (Cys) 이 약 1/3 정도 함유하는 사실을 확인 할 수 있었다. BLAST 결과를 토대로 선정 되어진 80개의 참고 서열 중 아미노산 레벨에서 가장 높은 스코어로 align 되는 서열들은 담수패인 Dreissena polymorpha (zebra mussel), Unio tumidus (swollen river mussel) and Crassostrea ariakensis (suminoe oyster) 등으로 나타났다. ClustalX 를 통해 multiple align 한 후 Neighbor-Joining 방법에 따라 phylodendrogram을 그려본 결과 Pisidium (Neopisidium)coreanum의 MT는 Dreissena polymorpha (Dp), Crassostrea gigas (Cg4), Crassostrea virginica (Cv7) 등의 생물들과 같은 군으로 묶이는 것을 관찰 할 수 있었다. Psipred 소프트웨어를 통해 2D 구조를 비교 분석 한 결과도 multiple align 및 phylodendrogram 결과와 밀접한 관계가 있음을 알 수 있었다. 이러한 결과를 통해 EST를 통해 밝혀진 Pisidium (Neopisidium) coreanum의 MT 서열은 근연종 들의 서열과 일치함을 알 수 있었으며 이러한 결과에 기인하여 MT 서열은 분류에 사용 될 수 있다고 사료된다.

• 한국항만경제학회지
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• 제30권3호
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• pp.163-185
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• 2014

도시가 발전하기 위해서는 다양한 자원과 성장에 필요한 제반조건과 총체적인 환경을 요구하고 있다. 도시의 성장과 발전은 역사 문화 경제 사회 공간 제도적 요인들이 서로 영향을 주면서 다양한 변화를 통하여 발전하고 있다. 그러나 항만이 입지하고 있는 배후지역의 도시개발계획이나 지역경제 활성화에 있어서는 원활한 경제활동이나 도시성장에 많은 도움을 주지 못하고 있다. 중앙정부나 지방자치단체의 행정환경 추세는 성숙한 분권형 국가운영시스템을 요구하고 있는 시대적 변화에 부응하지 못한 채 현실을 간과하고 있다. 이러한 이유에서 평택항과 광양항이 입지하고 있는 항만도시를 대상으로 배후지역 도시성장에 어떻게 영향을 주고 있는지에 대한 명확한 관계를 살펴보는 것은 의미가 있다. 본 연구의 목적은 항만의 입지가 배후지역 도시성장에 어떠한 영향을 미치고 있는지에 대한 분석을 통하여 항만과 배후도시와의 관계를 확인하고, 향후 항만개발과 운영방향에 대한 정책적 시사점을 탐색하는데 있다. 본 연구는 항만이 입지함에 따른 항만입지와 관련된 특정 요인이 평택항과 광양항에 어떠한 영향을 주고 있는지를 비교분석하였다. 분석결과 항만입지특성이 도시성장에 미치는 요인 중 수출입물동량이 평택항과 광양항 모두에 영향을 주고 있는 것으로 분석되었다. 이러한 맥락에서 항만당국인 중앙정부와 지방자치단체 간의 적극적인 계획과 협조가 반드시 병행되어야 한다. 또한 국가적 이미지 개선에 보탬이 되고 인적 물적 유인효과를 제고하는 지역적 특성이 반영된 정책을 수립하여 실행하는 전략을 추진할 필요가 있다. 따라서 본 연구의 결과는 중앙정부 주도의 항만정책 추진에 대한 대안을 제시하고 항만입지 특성과 배후도시 성장에 영향을 주는 다양한 추진 전략을 실행해야 하는 중앙정부와 지방자치단체의 협력적 관계를 모색할 수 있는 중요한 시사점을 제공할 수 있을 것으로 기대하고 있다.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2004년도 정기총회 및 제6최 특별 심포지움
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• pp.70-83
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• 2004

문화유산의 안전진단에 대한 가장 중요한 전제는 비파괴에 있다. 석조문화재에 대하여서도 비파괴진단과 보존을 위한 연구는 필수적이며 주요한 기술적 핵심이다. 비파괴진단 기술로서 지구물리탐사는 석조문화재 지반의 특징을 밝히는 중요한 역할을 하는데, 그 이유는 지반의 특성을 이해하는 것이 안전진단에 필수적이기 때문이다. 탐사사례로 국보급문화재인 경주 불국사의 다보탑(높이 10.4m, 기단폭 7.4m, 하중 123.2 ton)과 석가탑(높이 10.8m, 기단폭 4.4m, 하중 82.3ton)에 대한 지구물리탐사가 이루어졌다. 현재 석탑에서는 풍화는 물론 탑의 기울임 및 지대석의 어긋남 현상들이 관찰된다. 두 탐을 구성하는 석재의 역학적 성질을 위해 초음파 속도 측정을 실시하였고 천부지하구조를 위해 탄성파, 전기비저항, 지하레이더 등의 비파괴 복합 지구물리탐사를 석탑 주변에서 수행하였다. 초음파 속도범위는 석가탑에서는 1217${\~}$4403 m/s이며, 다보탑에서는 584${\~}$5845 m/s이며 이로부터 추정한 일축강도 평균치는 각각 463 kg/$cm^2$, 409 kg/$cm^2$이다. 탄성파 속도 분포에서는 다보탑 지반이 더 큰 속도를 보여 상대적으로 석가탑 지반보다 견고함을 보여준다. 대체로 석탑지반의 전기비저항은 최대 2200 $\Omega$m이며 200 $\Omega$m내외의 외부지반보다 더 높은 값을 보인다. 복합 지구물리탐사 결과를 종합하면 다보탑지반의 형태는 팔각형(한 변은 6 m)으로 그 깊이는 약 4 m 이나, 석가탑지반은 약 8${\times}$10 m의 직사각형 형태로 깊이는 약 3 m 이다. 이는 석탑 건립 당시 약 $8ton/m^2$의 탑 하중을 견디기 위해 구축한 기초구조로 해석한다. 대체로 두 석탑의 북서쪽 부분이 주변지역보다 낮은 탄성파 속도와 낮은 비저항 값이 관찰되는데 이 부분은 연약한 지반으로 판단하며 각 석탑이 북북서쪽 방향으로 기우는 원인으로 판단한다.

• Asia pacific journal of information systems
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• 제19권2호
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• pp.1-42
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• 2009

In a knowledge-based society, a firm's intellectual capital represents the wealth of ideas and ability to innovate, which are indispensable elements for the future growth. Therefore, the intellectual capital is evidently recognized as the most valuable asset in the organization. Considered as intangible asset, intellectual capital is the basis based on which firms can foster their sustainable competitive advantage. One of the essential components of the intellectual capital is a social capital, indicating the firm's individual members' ability to build a firm's social networks. As such, social capital is a powerful concept necessary for understanding the emergence, growth, and functioning of network linkages. The more social capital a firm is equipped with, the more successfully it can establish new social networks. By providing a shared context for social interactions, social capital facilitates the creation of new linkages in the organizational setting. This concept of "person-environment fit" has long been prevalent in the management literature. The fit is grounded in the interaction theory of behavior. The interaction perspective has a fairly long theoretical tradition, beginning with proposition that behavior is a function of the person and environment. This view asserts that neither personal characteristics nor the situation alone adequately explains the variance in behavioral and attitudinal variables. Instead, the interaction of personal and situational variables accounts for the greatest variance. Accordingly, the person-environment fit is defined as the degree of congruence or match between personal and situational variables in producing significant selected outcomes. In addition, information systems acceptance factors enable organizations to build large electronic communities with huge knowledge resources. For example, the Intranet helps to build knowledge-based communities, which in turn increases employee communication and collaboration. It is vital since through active communication and collaborative efforts can employees build common basis for shared understandings that evolve into stronger relationships embedded with trust. To this aim, the electronic communication network allows the formation of social network to be more viable to rapid mobilization and assimilation of knowledge assets in the organizations. The purpose of this study is to investigate: (1) the impact of person-environment fit(person-job fit, person-person fit, person-group fit, person-organization fit) on social capital(network ties, trust, norm, shared language); (2) the impact of information systems acceptance factors(availability, perceived usefulness, perceived ease of use) on social capital; (3) the impact of social capital on personal performance(work performance, work satisfaction); and (4) the mediating role of social capital between person-environment fit and personal performance. In general, social capital is defined as the aggregated actual or collective potential resources which lead to the possession of a durable network. The concept of social capital was originally developed by sociologists for their analysis in social context. Recently, it has become an increasingly popular jargon used in the management literature in describing organizational phenomena outside the realm of transaction costs. Since both environmental factors and information systems acceptance factors affect the network of employee's relationships, this study proposes that these two factors have significant influence on the social capital of employees. The person-environment fit basically refers to the alignment between characteristics of people and their environments, thereby resulting in positive outcomes for both individuals and organizations. In addition, the information systems acceptance factors have rather direct influences on the social network of employees. Based on such theoretical framework, namely person-environment fit and social capital theory, we develop our research model and hypotheses. The results of data analysis, based on 458 employee cases are as follow: Firstly, both person-environment fit(person-job fit, person-person fit, person-group fit, person-organization fit) and information systems acceptance factors(availability perceived usefulness, perceived ease of use) significantly influence social capital(network ties, norm, shared language). In addition, person-environment fit is a stronger factor influencing social capital than information systems acceptance factors. Secondly, social capital is a significant factor in both work satisfaction and work performance. Finally, social capital partly plays a mediating role between person-environment fit and personal performance. Our findings suggest that it is vital for firms to understand the importance of environmental factors affecting social capital of employees and accordingly identify the importance of information systems acceptance factors in building formal and informal relationships of employees. Firms also need to reflect their recognition of the importance of social capital's mediating role in boosting personal performance. Some limitations arisen in the course of the research and suggestions for future research directions are also discussed.

• Radiation Oncology Journal
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• 제14권1호
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• pp.77-85
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• 1996

목적 : 다엽콜리메이터를 이용하여 부정형의 치료부위를 편리하고 정확히 차폐하며 삼차원 입체조형치료를 원활히 수행하기 위하여 다엽콜리메이터의 차폐특성을 계측하고 치료계획을 위한 최적방법을 확정한다. 대상 및 방법 : 차폐폭이 1cm이고 길이가 15cm인 52개의 금속차폐엽들이 양방향 각각 26개로 구성되어 컴퓨터계획에 의거 여러모양의 차폐면을 구사할 수 있는 다엽콜리메이터(Multileaf collimator)를 대상으로 방사선 치료에 요구되는 고에너지 방사선의 출력선량율, 차폐 및 투과효과, 반음영, 조직내 선량분포등을 전리함측정기와 열형광측정기 및 필름 선량측정방법을 이용하여 계측하였다. 다엽콜리메이터의 계단식 반음영 측정은 고체팬텀과 비디오밀도측정기를 이용하여 실효반음영(Effective penumbra)과 일반적반음영(General penumbra)으로 구분 평가하였다. 결과 : 다엽콜리메이터의 출력선량율은 표준차폐조리개에 비교하여 출력 선량율이 $1-2\%$ 증가 되었으며 치료오차 이내로 평가되었다. 다엽콜리메이터의 방사선투라 선량율은 6-10MV X선에서 평균 $2\%$로 표준차폐조리개보다 컸지만 혼합차폐벽돌보다 적었다. 원형으로 형성된 차폐엽 끝면의 조사선량은 약 $20\%$증가 되었으며 엽과 엽사이의 선량은 6mm 폭의 $5\%$증가로 심부치료에 영향이 없었다. 다엽콜리메이터의 실효반음영($20-80\%$)은 약 6mm로서 혼합차폐벽돌과 거의 같았으나 중심선에서 벗어날수록 $2-3\%$증가되었다. 다엽콜리메이터에 의한 계단식 모양의 반음영은 6-10MV x-선에서 차폐면 경사각이 45도일 때 약 11mm로 가장 컸으며 방사선속에 평행히 절단된 차폐벽돌보다 약 5mm 더 증가되었다. 결론 : 다엽콜리메이터는 1cm폭의 차폐엽들로 구성되어 계단식 차폐면에 대한 반음영이 다소 증가되고 있지만 조직내부의 다문조사 경우 반음영이 완화되므로 부정형 조사면 차폐에 적당하며 방사선 입체조형치료를 수행할 수 있는 가장 적당한 차폐기구로 생각된다.