• Korean Journal of Radiology
• /
• 제22권9호
• /
• pp.1514-1524
• /
• 2021

Objective: To develop a radiomics risk score based on dynamic contrast-enhanced (DCE) MRI for prognosis prediction in patients with glioblastoma. Materials and Methods: One hundred and fifty patients (92 male [61.3%]; mean age ± standard deviation, 60.5 ± 13.5 years) with glioblastoma who underwent preoperative MRI were enrolled in the study. Six hundred and forty-two radiomic features were extracted from volume transfer constant (K^trans), fractional volume of vascular plasma space (V_p), and fractional volume of extravascular extracellular space (V_e) maps of DCE MRI, wherein the regions of interest were based on both T1-weighted contrast-enhancing areas and non-enhancing T2 hyperintense areas. Using feature selection algorithms, salient radiomic features were selected from the 642 features. Next, a radiomics risk score was developed using a weighted combination of the selected features in the discovery set (n = 105); the risk score was validated in the validation set (n = 45) by investigating the difference in prognosis between the "radiomics risk score" groups. Finally, multivariable Cox regression analysis for progression-free survival was performed using the radiomics risk score and clinical variables as covariates. Results: 16 radiomic features obtained from non-enhancing T2 hyperintense areas were selected among the 642 features identified. The radiomics risk score was used to stratify high- and low-risk groups in both the discovery and validation sets (both p < 0.001 by the log-rank test). The radiomics risk score and presence of isocitrate dehydrogenase (IDH) mutation showed independent associations with progression-free survival in opposite directions (hazard ratio, 3.56; p = 0.004 and hazard ratio, 0.34; p = 0.022, respectively). Conclusion: We developed and validated the "radiomics risk score" from the features of DCE MRI based on non-enhancing T2 hyperintense areas for risk stratification of patients with glioblastoma. It was associated with progression-free survival independently of IDH mutation status.

• 한국조경학회지
• /
• 제14권3호
• /
• pp.3-19
• /
• 1987

The purpose of this study was to investigate desirable width / height ratio of enclosed space and to offer basic information for the design of enclosed spaces. The data of this study were gathered from the experiment through simulation. Photographic sampling of 7 campus sites located in Kwanak campus of Seoul National University and slides of perspective drawings of enclosed spaces with various D/H ratio (12, 1, 2, 4, 6, 9, 12)were used for simulation. A response format was made using the method of paired comparison and students from various departments were randomly selected for evaluation. In the method of analysis of data Thurstone's equation of Comparative Judgement was used for calculating preference score. A1so non-linear regression analysis was used for finding out relations between preference and D/H ratio. The other method of data analysis were correlation, Chi - test. And the results were summarized as follows. 1. In sketch simulation the ratio of D/H 4 got the highest preference store. This result suggests that desirable D/H ratio of enclosed space is D/H 4. And at the lower range of D/H ratio, as ratio increases, the preference score increases. At the higher range of D/H ratio, however, as ratio increases, the preference score starts to decrease from the cardinal point of D/H 4. 2. In campus photograph simulation preference is influenced by slope, elevation change of floor, trees, lawn area, familiarity, space arrangement, and exterior shape of building besides D/H ratio. 3. The preference virtue was not significantly affected by order effect. This result suggests that order effect can be ignored in the study of visual preference. 4. There are so many factors related to preference that it is difficult to explore those factors without scientific information based on scientific method. We must carry out study for scientific approach of planning and design based on precise, complete simulation technique.

• 한국항공우주학회지
• /
• 제41권11호
• /
• pp.883-890
• /
• 2013

군용 항공기의 개발과정 중 전투 생존성 분석은 반드시 거쳐야 할 필수 과정이다. 군용 항공기의 전투 생존성 분석을 위한 방법은 M&S 기법 적용이 일반적이며 필요시 최종단계에서 Live Fire Test를 거친다. 본 연구에서는 비용대비 효과도를 고려하여 M&S기법을 통해 개념설계단계에서 신속하게 정성적으로 전투 생존성을 분석할 수 있는 연구를 수행하였다. 본 연구를 위하여 필수사건 및 필수요소 분석기법, 몬테카를로 시뮬레이션 등 확률, 통계기법들을 이용한 '확률변수 가중치 환산법' 알고리즘을 고안하여 제시하였다.

• 우주기술과 응용
• /
• 제1권3호
• /
• pp.337-355
• /
• 2021

본 논문은 SAR 위성 기술의 현황을 조사하여 향후 우리나라 HRWS SAR (High Resolution Wide Swath Synthetic Aperture Radar) 위성을 개발하기 위한 전략을 제안하기 위해 만들어졌다. 현황조사를 통해, 최신 SAR 기술 동향은 SAR 위성 영상을 보다 적극적으로 활용하기 위해 DBF(Digital Beam-Forming), SCORE(SCan-On-REceive), DPCA(Displaced Phase Center Antenna), 간섭계, 그리고 편파 기술을 사용하는 것이라는 것을 알 수 있었다. 이와 같은 최신 SAR 기술 동향 및 해외 HRWS SAR 개발 사례를 기반으로, 수년 내로 발사가 예정된 KOMPSAT-6(KOrea Multi-Purpose SATellite-6)를 사용하여 DPCA 및 SCORE 기술을 개발하고, 결국에는 전지구를 일주일 간격으로 관측할 수 있는 HRWS SAR 위성을 개발하는 것을 향후 우리나라 HRWS SAR 위성 개발을 위한 전략으로 제안하였다.

• 교육시설
• /
• 제16권4호
• /
• pp.79-88
• /
• 2009

To enhance the administrational efficiency and for university facility and space management to be public, this research suggests a competent and an objective evaluation system and index. The study will assist national and university finances to contribute towards advanced education. Furthermore, figure out the space management condition of national university by utilizing the evaluation system, and through that suggesting efficient special management method. According to the result of this study, evaluation system for university facility can be widely divided into seven categories; system preparation, members conference, propriety of space allocation, propriety of management system, space use ratio, time control of space use, imposition index of surplus use. Based on these subdivisions, the space management category contains 19 evaluation items and the marking system allows perfect score of 100 points. In result of examining space management condition using the evaluation system, space management was well enforced in research focused university group where as in education centered university group, it shows relatively low enforcement. It also illustrated that efforts of evaluation items were required in categories of imposition index of surplus use and special use ratio in order for efficient space management.

• 한국농촌건축학회논문집
• /
• 제18권4호
• /
• pp.33-40
• /
• 2016

The campus outdoor space in each city is a very important space for students and local residents. Especially, for students, indoor space such as classroom is the main place to learn knowledge. But the outdoor space provides an opportunity to interact with people in other sectors and it also gives an opportunity that can make students sense the flow of the times. Moreover, students have the opportunity to integrate knowledge of the other fields in the outdoor space. The campus also provides an important resting place for residents. Therefore the campus should be convenient for both local residents and students, and should be designed to let students and local residents communicate with each other in outdoor space. This study attempts to identify the problems of the outdoor space in such a point. The high scores of campus evaluation indexes are as follows: First, the lighting in the favorite space and installing seats in a green space of the vestibule get the highest score. Also, separation of a sidewalk and a roadway, the ease of holding events, simple food and beverage near the entrance, the interacting place of people, the resting place near the porch in cold winter, the lighting in a bus stop and parking lot also get good evaluations.

• 한국주거학회논문집
• /
• 제18권6호
• /
• pp.93-101
• /
• 2007

This study was to find out users' satisfaction on the dormitory of high school in Jeonju City and to propose it's physical environmental improvement directions. This was performed by a questionnaire survey method, and the questionnaire was designed by researchers considering relative literatures. Data were collected from 200 students, who had been dwelling 4 high school dormitories in Jeonju City. By analyzing those data, findings were as follows: 1) Users of students were satisfied the whole of their dormitory; facilities, spaces, and living. 2) They were highly concerned about a library and a personal unit space in their dormitory. 3) They needed their personal unit space to be designed bedroom+bathroom type with 2 persons' sharing and be equipped one story bed and desk furniture. Also, they needed improvement on heating & cooling, small space and indoor air quality of unit space. 4) The users' satisfaction on unit space were 2.88, and their satisfaction of the technical factor was 2.71 that was the lowest score in them. And The functional factor was highly effected their satisfaction. 5) The space utility and the space size of functional factor, the soundproof, the heating/ventilation and the indoor quality of technical factor, and the privacy of behavior factor were highly correlative to their satisfaction of unit space.

• 한국축산시설환경학회지
• /
• 제18권3호
• /
• pp.157-164
• /
• 2012

동물복지관점에서 많은 비난을 받아왔던 관행적 분만틀의 사용을 배제하고 넓은 분만시설의 면적의 제공이 모돈의 생산성 및 자돈의 성장능력에 미치는 영향을 좁은 분만시설로서 분만틀을 이용하여 비교하였다. 1. 좁은 분만시설과 넓은 분만시설에서 모돈의 사료섭취량, 등지방 두께, 그리고 체평점에는 아무런 차이가 없었다. 하지만 이유시와 분만시 등지방 두께와 체평점의 차이는 넓은 분만시설에서 유의적으로 감소하였다. 또한 모돈의 재귀발정일도 좁은 분만시설보다 넓은 분만시설에서 유의적으로 감소하였다. 2. 모돈의 분만능력은 분만시설의 면적에 의한 영향은 없었다. 하지만 넓은 분만시설 에서 분만전 모돈의 행동 자유가 분만시 신생자돈의 생존율에 영향하는 것으로 나타났다. 3. 분만시설 면적에 따른 차이는 이유자돈수, 자돈의 증체량에는 아무런 영향이 없었으나 넓은 분만시설에서 자돈의 폐사율이 증가하는 것으로 나타났다. 이상의 결과로부터, 모돈의 복지를 위해 넓은 분만시설은 모돈의 번식능력에는 효과가 있었으나 자돈의 폐사율 증가라는 생산성의 관점에서는 다소 불리한 것으로 판단되며 또한 자돈의 폐사율 증가에 대한 원인을 모돈과 자돈의 행동학적 관점에서 면밀히 연구할 필요가 있을 것으로 판단된다.

• 대한감각통합치료학회지
• /
• 제4권1호
• /
• pp.47-55
• /
• 2006

Objective : The purpose of this study was to evaluate the correlation between visual perception ability and activities of daily living(ADL) in the children with spastic diplegia who were treated at developmental disabilities children salutary institute. Method : The subject were consisted of 8 children with spastic diplegia(mean age, 10). The visual perception ability was measured by the Developmental Test of Visual Perception(DTVP) and by the Functional Independence Measure for Children(WeeFIM) to evaluate activities of daily living. Collected data analysis were completed by using correlation analysis. Results : Visual perception ability of children with spastic diplegia is the highest in Position in Space(PS) score, and is the lowest in Visual-Motor coordination(VM) score. Average visual perception performance of children with spastic diplegia is the highest in SR(Spatial relationship) score, and is the lowest in VM score. In activities of daily living, eating component were significantly correlated with Visual-Motor coordination. Conclusions : Therefore, accurate evaluation of visual perception ability and visual perception training for children with spastic diplegia will be important to improve patient's activities of daily living skill.

• Journal of Korean Neurosurgical Society
• /
• 제57권3호
• /
• pp.167-173
• /
• 2015

Objective : Removal of blood from subarachnoid space with a lumbar drainage (LD) may decrease development of cerebral vasospasm. We evaluated the effectiveness of a LD for a clinical vasospasm and outcomes after clipping of aneurysmal subarachnoid hemorrhage (SAH). Methods : Between July 2008 and July 2013, 234 patients were included in this study. The LD group consisted of 126 patients, 108 patients in the non LD group. We investigated outcomes as follow : 1) clinical vasospasm, 2) angioplasty, 3) cerebral infarction, 4) Glasgow outcome scale (GOS) score at discharge, 5) GOS score at 6-month follow-up, and 6) mortality. Results : Clinical vasospasm occurred in 19% of the LD group and 42% of the non LD group (p<0.001). Angioplasty was performed in 17% of the LD group and 38% of the non LD group (p=0.001). Cerebral infarctions were detected in 29% and 54% of each group respectively (p<0.001). The proportion of GOS score 5 at 6 month follow-up in the LD group was 69%, and it was 58% in the non LD group (p=0.001). Mortality rate showed 5% and 10% in each group respectively. But, there was no difference in shunt between the two groups. Conclusion : LD after aneurysmal SAH shows marked reduction of clinical vasospasm and need for angioplasty. With this technique we have shown favorable GOS score at 6 month follow-up.