• Journal of Forest and Environmental Science
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• 제34권6호
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• pp.419-428
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• 2018

Spatial point-patterns analyses were conducted to provide insight into the ecological process behind competition and mortality in two lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm.) stands, one in the Lower Foothills, and the other in the Upper Foothills natural subregions in the boreal forest of Alberta, Canada. Spatial statistical tests were applied to live and dead trees and included Clark-Evans nearest neighbor statistic (R), nearest neighbor distribution function (G(r)), and a variant of Ripley's K function (L(r)). In both lodgepole pine plots, the results indicated that there was significant regularity in the spatial point-pattern of the surviving trees which indicates that competition has been a key driver of mortality and forest dynamics in these plots. Dead trees generally showed a clumping pattern in higher density patches. There were also significant bivariate relationships between live and dead trees, but the relationships differed by natural subregion. In the Lower Foothills plot there was significant attraction between live and dead tees which suggests mainly one-sided competition for light. In contrast, in the Upper Foothills plot, there was significant repulsion between live and dead trees which suggests two-sided competition for soil nutrients and soil moisture.

• 영미문화
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• 제9권1호
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• pp.163-184
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• 2009

Sherman Alexie deals with reservation realism in The Lone Ranger and Tonto Fistfight in Heaven and Smoke Signals. By reservation realism he means American Indian traditions and its problems like alcoholism, violence, unemployment, depression, and poverty on the reservation. It cannot be denied that the traditional ceremonies have played significant roles in making it possible for American Indians to keep their own ethnic identities. It is, however, also true that the same traditions have prevented them from embracing modernity. Alexie believes that it is high time that Indians living on the reservation discarded the old tradition of racial exclusiveness for a gradual crossing of cultural borders. What is seriously needed on today's reservation is not the historic figure of Crazy Horse, a stoic and masculine warrior in the late 19th century, but Sacagawea, a Shoshoni Indian who helped Meriwether Lewis and William Clark to explore the American West in the early 19th century. When asked to be more specific about cross cultural examples, Alexie proposes successful Indian doctors and lawyers as role models on the reservation.

• 정보보호학회논문지
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• 제10권2호
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• pp.79-92
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• 2000

기업환경에서 정보의 무결성은 중요한 보안 요구사항이다 의무분리 정책의 목적은 정보의 무결성을 필요로 하는 연산들을 여러 역할이나 사용자에게 분산시킴으로써 조직 내에서 관리하는 무결성 침해 가능성을 최소화하는 것이며 이것은 상업적 응용분야에서 중요하다. 전통적인 임의적 접근제어와 강제적 접근제어 정책의 대안인 역할 기반의 접근제어 기법은 응용에 따라 보호 객체들에 대한 접근을 역할들로 분류하여 단순한 권한 관리를 제공하며 의무분리 정책을 시행하기에 적합하다. 본 논문에서는 역할 기반의 접근제어에서 기존의 의무분리 안전성 조건의 취약성을 보완하여 응용 프로그램의 실행단위인 클래스에 기반한 개선된 동적 의무분리 기법을 제안하고 상호 배타적인 부트랜잭션들을 포함하고 있는 중첩-트랜잭션을 대상으로 이를 적용한다. 또한 여러 작업들이 동시에 실행되는 환경에서 감염된 트로이언 목마에 의해 발생될수 있는 정보의 유출 문제를 해결하고자 작업간 정보의 비밀성을 보장하는 동적의무분리 모델을 제시한다. 제안한 모델은 기존의 무결성 보장을 위해 제시되었던 Clark-Wilson 모델과 다른 의무분리 모델에 비해 관리가 용이하며, 동적으로 유지 관리되어야 하는 데이터의 양이 적고 객체 접근 확인 절차가 단순하여 구현방법이 용이한 장점이 있다 그리고 기존 의무분리 모델에서 고려되지 않은 병렬 수행 환경에서 작업 사이의 정보 유출 문제를 해결한다.

• 한국콘텐츠학회논문지
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• 제21권3호
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• pp.552-560
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• 2021

본 연구의 목적은 고혈압 및 당뇨병 환자의 건강 관련 의사결정에 대한 참여경험을 탐색하는 것이다. 당뇨병 또는 고혈압의 만성질환을 진단받고 1년 이상 보건소에 정기적으로 방문하였던 장년기 환자 11명이 참여하였다. 자료의 수집은 개별 인터뷰를 통해 시행되었으며, Braun과 Clark 가 제시한 주제 분석법을 적용하여 분석되었다. 연구 결과 6개의 하위주제와 3개의 주제가 도출되었다. 각각의 주제는 '짧은 면담시간을 효율적으로 활용하기 위해 노력함', '의료인에게 한정된 영역 안에서 응답함', '건강관리에 대한 지속적인 동기부여가 결여됨'이었다. 본 연구 결과는 만성질환자의 의사결정에 대한 참여를 독려하기 위해 정확하고 충분한 건강정보를 제공하고 지지적인 태도로 환자의 동기를 부여해야 할 필요성을 제시하였다.

• Nuclear Engineering and Technology
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• 제55권2호
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• pp.432-442
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• 2023

Characterizing the behavior of nuclear reactor plate fuels is vital to the progression of advanced fuel systems. The states of pre- and post-irradiation plates need to be determined effectively and efficiently prior to and following irradiation. Due to the hostile post-irradiation environment, characterization must be completed remotely. Laser-based characterization techniques enable the ability to make robust measurements inside a hot-cell environment. The Laser Shock (LS) technique generates high energy shockwaves that propagate through the plate and mechanically characterizes cladding-cladding interfaces. During an irradiation campaign, two Idaho National Laboratory (INL) fabricated MP-1 plates had a fuel breach in the cladding-cladding interface and trace amounts of fission products were released. The objective of this report is to characterize the cladding-cladding interface strengths in three plates fabricated using different fabrication processes. The goal is to assess the risk in irradiating future developmental and production fuel plates. Prior LS testing has shown weaker and more variability in bond strengths within INL MP-1 reference plates than in commercially produced vendor plates. Three fuel plates fabricated with different fabrication processes will be used to bound the bond strength threshold for plate irradiation insertion and assess the confidence of this threshold value.

• Nuclear Engineering and Technology
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• 제55권6호
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• pp.2195-2205
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• 2023

One of the salient nuclear fuel performance parameters for new fuel types under development is changes in fuel thickness. To test the new commercially fabricated U-10Mo monolithic plate-type fuel, an irradiation experiment was designed that consisted of multiple mini-plate capsules distributed within the Advanced Test Reactor (ATR) core, the mini-plate 1 (MP-1) experiment. Each capsule contains eight mini-plates that were either fueled or "dummy" plates. Fuel thickness changes within a fuel assembly can be characterized by measuring the gaps between the plates ultrasonically. The channel gap probe (CGP) system is designed to measure the gaps between the plates and will provide information that supports qualification of U-10Mo monolithic fuel. This study will discuss the design and the results from the use of a custom-designed CGP system for characterizing the gaps between mini-plates within the MP-1 capsules. To ensure accurate and repeatable data, acceptance and calibration procedures have been developed. Unfortunately, there is no "gold" standard measurement to compare to CGP measurements. An effort was made to use plate thickness obtained from post-irradiation measurements to derive channel gap estimates for comparison with the CGP characterization.

• Journal of Astronomy and Space Sciences
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• 제40권4호
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• pp.149-171
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• 2023

ShadowCam is a National Aeronautics and Space Administration Advanced Exploration Systems funded instrument hosted onboard the Korea Aerospace Research Institute (KARI) Korea Pathfinder Lunar Orbiter (KPLO) satellite. By collecting high-resolution images of permanently shadowed regions (PSRs), ShadowCam will provide critical information about the distribution and accessibility of water ice and other volatiles at spatial scales (1.7 m/pixel) required to mitigate risks and maximize the results of future exploration activities. The PSRs never see direct sunlight and are illuminated only by light reflected from nearby topographic highs. Since secondary illumination is very dim, ShadowCam was designed to be over 200 times more sensitive than previous imagers like the Lunar Reconnaissance Orbiter Camera Narrow Angle Camera (LROC NAC). ShadowCam images thus allow for unprecedented views into the shadows, but saturate while imaging sunlit terrain.

• Archives of Plastic Surgery
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• 제34권5호
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• pp.557-561
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• 2007

Purpose: Malignant melanoma is a fatal tumor arising in the melanocytic systems of the skin. The incidence of malignant melanoma, formerly considered a rare tumor in Korea, is observed to increase. The aim of this study is to analyze the clinical and histopathological pattern of malignant melanoma in one institute. Methods: Thirty patients with ages ranging from 33 to 80 years, diagnosed as malignant melanoma at our skin tumor department, were enrolled in a retrospective study over a 6 year period(2000. 9-2006. 7). The analyzed data included age, sex, location, duration before diagnosis, clinical type, level of invasion, and stage. Results: The cases were identified and analyzed by clinical and histopathologic study. The male to female ratio was 1:1.7. Lower extremities(especially, feet) were favored sites. The majority of cases were acral lentiginous melanoma(40%), followed by nodular melanoma (36.7%), superficial spreading melanoma(20%) in this study. Clark level IV was predominant in histopathologic study. There was merely narrow gap among each stage by AJCC. Conclusion: The clinicopathological characteristic of melanoma in our patients is quite different with that in the West. In this retrospective study, primary lesions of the foot were predominant with melanoma, and a high percentage of these were classified pathologically as acral lentiginous melanomas. Patients had a more advanced stage of disease at first presentation and a more deeply invasive primary lesion than Western patients. These suggest that malignant melanoma has a worse prognosis in our patients than in the West. So, further organized prospective studies are needed to approach the prudent and accurate diagnosis and management of melanoma in Korea.

• The Korean Journal of Physiology
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• 제15권1호
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• pp.3-8
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• 1981

Studies have been conducted to test the effect of Ginseng alcohol extract on the membrane potentials of frog skeletal muscle. The gastrocnemius muscle was isolated and placed in a chamber containing the Clark-frog Ringer solution. Membrane potentials were recorded using microelectrodes filled with 3 M KCI and muscle was electrically stimulated to obtain action potential. Changes in both the action potential and the resting membrane potential were observed after adding an appropriate amount of Ginseng alcohol extract in the perfusing Ringer solution. The results obtained from 346 muscle cells are summarized as follows : 1) The average resting membrane potential of the normal frog gastrocnemius muscle cell was -92.8 mV and the peak of the action potential reached at 29.8 mV. 2) Both the resting membrane potential and the peak of the action potential decreased by Ginseng alcohol extract, the effect being proportional to the dose of Ginseng alcohol extract. 3) The resting membrane potential and the peak of the action potential continuously decreased until about 40 min after Ginseng addition and leveled off thereafter. The potentials recovered to its original value after Ginseng was washed out. 4) The resting membrane potential was more sensitive to the Ginseng alcohol extract than was the action potential. These results strongly suggest that Ginseng alcohol extract increases both the $Na^+$ and $K^+$ permeability in the skeletal muscle cell membrane.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8161-8169
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• 2014

Background: Cancer stem cells (CSC) are populations of cells responsible for tumor initiation, progression and therapeutic resistance in many cancers. In the present study, we aimed to investigate the expression pattern and clinical significance of two CSC markers, CD133 and Nestin, in a series of skin tumors. Materials and Methods: One hundred and thirteen paraffin blocks from skin cancers including 16 (14%) cases of melanoma, 37 (33%) of squamous cell cancer (SCC) and 60 (53%) of basal cell cancer (BCC) were collected and assembled in a tissue microarray (TMA). The samples were immunohistochemically examined for the expression of CD133 and Nestin. Expression of these markers was also correlated with clinicopathological parameters. Results: A significant difference was observed in the expression of CD133 and Nestin in melanomas, SCC and BCC (p value=0.001). Furthermore, the level of expression was significantly higher in the melanomas compared to the SCC and BCC tumors. Expression of CD133 in the melanoma was significantly associated with increased tumor invasiveness (p value=0.05), a higher rate of metastasis (p value=0.04) and the presence of ulceration (p value=0.02). Increased expression of Nestin was observed in metastatic melanoma (p value=0.04), while no statistically significant correlation was found with other clinicopathological parameters including Breslow thickness, Clark level and ulceration. Conclusions: Elevated expression levels of CD133 and Nestin in the melanomas are associated with advanced disease, with more aggressive and metastatic skin tumors. Therefore, these markers could be potential therapeutic targets for malignant tumors of the skin.