• Tunnel and Underground Space
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• v.27 no.5
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• pp.333-342
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• 2017

In this study, the heterogeneity of internal structure of various igneous rocks acquired in Korea was quantified and correlated with the seismic velocity and the point load strength. Three-dimensional X-ray Computed Tomography (CT) was used to obtain information on the internal structure of the rock specimen, and the representative unit length (LR) was calculated by applying a statistical technique to the CT images. We also proposed an estimation equation to predict the mechanical properties of rocks from the relationship between LR, acoustic velocity and point load strength. In the proposed method, it is shown that the characterization of internal structure of rocks could be utilized as an indirect index to account for the mechanical behavior of rocks by substituting physical laboratory testing for non-destructive test.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.2
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• pp.783-787
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• 2011

This study was attempted to identify factors related to the health habit practice in stroke patients of some area. Data was surveyed using interview and questionnaires by 142 stroke patients who visited a general hospital which was located in Seoul from May 3 to June 3, 2010. The results were as follows ; First, there was significantly negative correlation between health information and unpredictability(r=-0.264, p<0.01), and positive correlation between uncertainty and stress(r=0.582, p<0.01). Secondly, as a result of multiple regression analysis,, health habit practice of stroke patients was significantly influenced by age($R^2$=0.62, p=0.000), unpredictability($R^2$=0.096, p=0.006), health information($R^2$=0.055, p=0.005), sex($R^2$=0.068, p=0.003), the usage of stroke therapy($R^2$=0.041, p=0.017). In conclusion, strategies for enhancing health information and reducing uncertainty are needed to promote health habit practice in patients with stroke.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.4
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• pp.293-305
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• 2010

Ovarian hyperstimulation syndrome (OHSS) is a life-threatening iatrogenic complication of ovulation induction. Before ovarian stimulation, identification of patients vulnerable to developing OHSS is necessary. And ovarian stimulation should be started with low doses of gonadotropin or GnRH antagonist protocol. During monitoring of ovarian stimulation with risk of OHSS, coasting, low doses hCG and GnRH agonist for triggering ovulation are considered. If severe OHSS is predicted, cycle cancellation and cryopreservation of all embryos should be considered to reduce late-onset OHSS and morbidity. And metformin and dopamine agonist for reducing OHSS are being proposed as a prophylactic treatment for OHSS.

• Journal of the Korean Solar Energy Society
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• v.23 no.1
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• pp.39-47
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• 2003

In order to test the predictability of the wind resource assessment computer code in our country a field experiment and prediction by WAsP has been compared. A field experiment has been performed in Songdang province, Jeju island, composed of sea, inland flat terrain, a high and a low slope craters. For this experiment, four meteorological towers have been installed at seashores, inland flat and on a crater. Wind resource at one site is predicted by WAsF with the meteorological data at the other three sites. The comparisons show that the WAsP preditions give better agreement with experimental data by adjusting the roughness descriptions.

• 한국IT서비스학회:학술대회논문집
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• 2002.11a
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• pp.286-292
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• 2002

국내기업에서 대부분의 정보시스템이 정보시스템 수명주기로 불 때 운영단계로 진입하고 조직의 정보시스템의존도 및 시스템규모가 점점 늘어남에 따라서 정보시스템의 운영과정에서 발생되는 소프트웨어 유지보수에 투입되는 비용도 증가되고 있다. 그러나 소프트웨어유지보수 프로젝트에 소요되는 투입인력 규모예측에 관련된 연구는 소프트웨어개발부문에 비해 적은 것이 사실이다. 본 연구에서는 유지보수프로젝트를 대상 소프트웨어의 규모는 IFPUG에서 개발된 기능점수기법(function point model)을 적용하여 산정하고, 특정 소프트웨어유지보수 프로젝트 생산성에 영향을 미치는 유지보수환경, 프로덕트, 투입인력 등 3개 영역에서 도출된 총 10개 특성을 보정요소로 설정한 후, 유지보수프로젝트의 소요인력 규모를 추정하기 위한 비선형회귀모형을 제시하고 있다. 실제 수행된 26개 유지보수프로젝트로부터 수집한 실적데이터를 이용하여 이 모형을 실증 분석한 결과 유의한 모형임이 밝혀졌다.

• Annual Conference of KIPS
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• 2005.11a
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• pp.345-348
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• 2005

소프트웨어 개발 후 인도 전 테스트 단계중에 발생되는 테스트 노력 소요량을 고려한 소프트웨어 신뢰도 성장 모델을 제시하여 테스트 노력소요량 동태를 시간함수인 로지스틱 곡선으로 설명한다. 테스트 단계중에 소요되는 테스트노력의 양에 대한 결함 검출비를 현재의 결함 내용에 비례하는 것으로 가정하여 소프트웨어 신뢰도 성장 모델을 비동차 포아송 프로세스(NHPP)로 공식화하여, 이 모델을 이용하여 소프트웨어 신뢰도 척도에 대한 데이터 분석기법을 개발한다. 그간 여러 문헌에서 소프트웨어 신뢰도 향상 모델을 연구할 때 소프트웨어 테스트 중에 소요되는 테스트노력의 양으로서 지수함수 곡선, 레일레이 곡선, 웨이불 곡선을 사용해 왔다. 그러나, 모든 소프트웨어 개발 환경에서 지금까지 제시된 그러한 곡선중 하나에 의해서 테스트노력 소요 곡선을 표현하는 것은 적절하지 못하다는 것이 밝혀지고 있다. 본 논문에서는 로지스틱 테스트노력 곡선이 소프트웨어의 개발/테스트 노력곡선으로 적절하게 표현될 수 있다는 것과 실제 데이터를 근거로 하여 적용하여서 예측성이 매우 좋은 능력을 가지고 있다는 것을 보이고자 한다.

• Journal of the Korean Solar Energy Society
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• v.23 no.4
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• pp.21-27
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• 2003

The comparative performance of the WAsP in calculating the wind climate in complex terrain has been examined in order to test the predictability of the wind resource assessment computer code in our country. An analysis was carried out of predicted and experimental 10-min averaged wind data collected over 8 months at four monitoring sites in SongDang province, Jeju island, composed of sea, inland flat terrain, a high and a low slope craters. The comparisons show that the WAsP preditions give better agreement with experimental data by adjusting the roughness descriptions, the obstacle list.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.2
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• pp.86-102
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• 2012

For predictive flooded area susceptibility mapping, this study applied and verified probability model and the frequency ratio using a geographic information system (GIS) and frequency raio. Flooded areas were identified in the study area of field surveys, For predictive flooded area susceptibility mapping, this study applied and verified probability model and the frequency ratio using a geographic information system (GIS) and frequency raio. Flooded areas were identified in the study area of field surveys, and maps of the topography, geology, landcover and green infrastructure were constructed for a spatial database. The factors that influence flooded areas occurrence, such as slope gradient, slope, aspect and curvature of topography and distance from darinage, were calculated from the topographic database. Lithology and distance from fault were extracted and calculated from the geology database. The frequency ratio coefficient is overlaid for flooded areas susceptibility mapping as each factor's ratings. Then the flooded areas susceptibility map was verified and compared using the existing flooded areas. As the verification results, the frequency ratio model showed 82% in prediction accuracy. The method can be used to reduce hazards associated with flooded areas and to plan land use.

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.203-208
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• 2011

This study was to evaluate the efficacy of sanitizer concentrations and treatment time against two major toad-borne pathogenic microorganisms such as Escherichia coli and Staphylococcus aureus on a stainless steel surface. As a result, stainless steel, treated with 100 ppm of chlorine showed reduction of E. coli(1.56, 1.49, 1.95 log cfu/25 $cm^2$) and S. aureus(0.49, 0.88, 1.27 log cfu/25 $cm^2$) after 0, 5 and 10 min, but none was not detected in treatment with 200 ppm. The population of E. coli(0.73, 0.90, 1.55 log cfu/25 $cm^2$) and S. aureus(0.37, 1.00, 1.45 log cfu/25 $cm^2$) reduced in 35.5% ethanol treated group, but none was not detected in treatment with 70%. The population was reduced E coli(0.28, 0.64, 1.07 cfu/25 $cm^2$) and S. aureus(0.53, 0.87, 0.99 log cfu/25 $cm^2$) by treatment with 45.5 ppm of hydrogen peroxide, but none was not detected in treatment with 91 ppm. Quarternary ammonium compound with 100 ppm was reduced E. coli(0.82, 1.62, 1.71 log cfu/25 $cm^2$) and S. aureus(0.46, 0.93, 1.38 log cfu/25 $cm^2$), but none was not detected in treatment with 200 ppm. Predictive models of sterilization for all 4 disinfectants were suitable to use with $r^2$ value of higher than 0.94. These models may be of use to food services and manufacture of safe products by controlling E. coli and S. aureus without the need for further detection of the organisms.

• The Korean Journal of Applied Statistics
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• v.24 no.1
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• pp.83-92
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• 2011

This paper examines empirically Durham's (2008) asset pricing models to the KOSPI200 index. This model Incorporates the VKOSPI index as a proxy for 1 month integrated volatility. This approach uses option prices to back out implied volatility states with an explicitly speci ed risk-neutral measure and risk premia estimated from the data. The application uses daily observations of the KOSPI200 and VKOSPI indices from January 2, 2003 to September 24, 2010. The empirical results show that non-affine model perform better than affine model.