• Korean Journal of Biological Psychiatry
• /
• v.5 no.1
• /
• pp.3-16
• /
• 1998

The neurophysiological study has been widely used in search of the relationship between brain and behavior. The basic techniques for the animal experiments of this kind such as stereotaxic techniques, lesioning methods, the methods of electrical stimulation and recording, and confirmation of histological location were briefly reviewed. Nevertheless, the importance of complementary neurochemical, neuroanatomical and behavioral studies can not be neglected.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.37 no.6
• /
• pp.1-11
• /
• 2010

The purpose of this research is to identify satisfaction levels of the arboretum which will be provided in the Multifunctional Administrative City and to estimate the economic value of using choice experiments. The attributes were "Preservation", "Education", "Recreation", "Facility", "Accessibility" and the entrance fee. The main effects model was utilized to construct hypothetical alternatives. Calibration of the conjoint choice model revealed that 'wetlands' and 'forest trails' in "Preservation" and the "Recreation", respectively, were significant variables. This result indicates that respondents are willing to pay more for these if they are provided in the arboretum. Also, 'variety seeking' tendency, age, and income level positively influenced the provision of the arboretum. Involvement in preservation of natural environment, however, had a negative influence on the establishment of the arboretum. Because this study is the first attempt to estimate the economic valuation of an urban arboretum using choice experiment, there are several suggestions for future research in terms of determining the base level and inclusion of salient attribute levels.

• Proceedings of KOSOMES biannual meeting
• /
• 2017.11a
• /
• pp.127-127
• /
• 2017

• Proceedings of the Korea Water Resources Association Conference
• /
• 2007.05a
• /
• pp.1640-1644
• /
• 2007

본 연구에서는 안양천 유역에 대해 왜곡된 물순환을 건전화시키기 위한 유역통합관리 계획을 수립하였다. 대안의 효과분석은 HSPF 모형을 사용하였으며 평가지수는 건천화 방지와 수질개선 효과 요소로 구성되며 각각은 유역통합관리 6단계 결과를 모두 사용할 수 있도록 복합계획법과 지속가능성 개념(압력-상태-반응)을 활용하여 개발되었다. 특히 수량과 수질에 대한 가중치는 유역주민의 의견을 반영하기 위해 실험선택법으로 정량화하여 유역의 속성별로 달리 적용하였다. 대안은 평가지수에 따라 세 등급(Good, Acceptable, Poor)으로 나누어 제시하였다.

• Proceedings of the Korean Statistical Society Conference
• /
• 2003.10a
• /
• pp.263-268
• /
• 2003

Breiman, Friedman, Olshen and Stone(1984)의 전체탐색법에 의한 회귀나무는 상대적으로 많은 분리가 가능한 변수로 분리기준이 정해지는 편의 현상을 갖고 있다. 본 연구에서는 이런 문제점을 해결할 수 있는 알고리즘을 제안하여 변수선택편의가 없는 회귀나무를 만들고자 한다. 제안하는 알고리즘은 노드의 분리변수를 선택하는 단계와 그 선택된 변수에 의해 이진분리를 위한 분리점을 찾는 단계로 구성되어 있다. 예측변수 중에서 목표변수와 가장 밀접하게 연관된 예측변수는 예측변수의 자료의 종류에 따라 스피어만의 순위상관계수에 의한 검정 혹은 크루스칼-왈리스의 통계량에 의한 검정을 수행하여 가장 통계적으로 유의한 변수로 선택하였고, 선택된 변수에만 Breiman et al.(1984)의 전체선택법을 적용하여 분리점을 결정하였다. 모의실험을 통해 변수선택편의, 변수선택력 , 그리고 평균제곱오차 측면에서 Breiman et al. (1984)의 CART(Classification and Regression Trees)와 제안한 알고리즘을 서로 비교하였다. 또한, 두 알고리즘을 실제 자료에 적용하여 효율을 서로 비교하였다.

• The Korean Journal of Applied Statistics
• /
• v.28 no.5
• /
• pp.1035-1046
• /
• 2015

Variance components models incorporate various random factors in the form of linear models. There are two experimental Layouts for the classification of factors under variance components models: nested classification and crossed classification. We consider two-way variance components models and investigate the effect of experimental Layout on the performance of model selection criteria AIC and BIC. The effect of experimental Layout is studied through a simulation study with various combinations of parameters in a systematic fashion. The simulation study shows differences in performance of model selection methods between the two classification. There is a particular tendency to prefer the smaller model than the true model when the variance component of a nested factor becomes relatively larger than a nesting factor that is persistent even when the sample size is not small.

• The Korean Journal of Food And Nutrition
• /
• v.22 no.4
• /
• pp.696-700
• /
• 2009

The adaptability of dry rehydratable film for the qualitative evaluation of coliform bacteria and Escherichia coli was tested. In general, culture methods that employ lactose broth or desoxycholate lactose agar are used for qualitative tests of coliform bacteria. Culture using lactose broth showed a high detection yield and low selectivity when compared to the dry rehydratable film. However, culture methods that employ lactose broth required a long time(48 hrs) for qualitative tests of coliform bacteria and complicated procedures were required to prepare the medium. The detection of coliforms using desoxycholate lactose agar had a slightly higher selectivity than the dry rehydratable film method, but this difference was not statistically significant. However, the preparation of the desoxycholate lactose agar was complicated. EC broth for the detection of E. coli showed the highest detection yield and lowest selectivity; however, this method required complicated procedures for preparation of the medium as well. Overall, the dry rehydratable film had a slightly lower detection yield than the other methods. The detection yield of dry rehydratable film method was over 37.1% at a concentration of 1 cfu/$m{\ell}$. Additionally, the dry rehydratable film method showed high selectivity and did not require preparation. However, because the selectivity of the dry rehydratable film was high, it took a long time(36 hrs) to detect E. coli. Overall, these findings indicate that dry rehydratable film can be used for qualitative detection of coliforms and E. coli.

• Environmental and Resource Economics Review
• /
• v.27 no.3
• /
• pp.421-461
• /
• 2018

Windpower turbines have positive values for visitors with regard to tourism and learning. On the other hand, it is clear that windpower turbines have negative impact on the landscape, particularly when the level of landscape is high. The impact of windpower turbines on the visitor's value is composed of two elements: the viewingvalue which is independent of the level of landscape and the landscape value which varies with the level of landscape. The net visitor's value of windpower turbines is the sum of these two values with opposite signs. This study used a choice experimentation method to value the impact of windpower turbine construction in the mountainous area in Korea. This study estimated the viewing value, the landscape value and the visit value as the sum of the two values. The estimated results demonstrated a significantly positive viewing value, a significantly negative landscape value, and weakly negative net visit value in average.

• Journal of the Korean Data and Information Science Society
• /
• v.9 no.2
• /
• pp.179-188
• /
• 1998

Local polynomial regression estimation is the most popular one among kernel type regression estimator. In local polynomial regression function esimation bandwidth selection is crucial problem like the kernel estimation. When the regression curve has complicated structure variable bandwidth selection will be appropriate. In this paper, we propose a variable bandwidth selection method fully data driven. We will choose the bandwdith by selecting minimising estiamted MSE which is estimated by the pilot bandwidth study via croos-validation method. Monte carlo simulation was conducted in order to show the superiority of proposed bandwidth selection method.

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.06a
• /
• pp.228.1-228.1
• /
• 2010

선택적 CO 산화반응(PrOx)을 위한 Ru이 고분산 담지된 $Ru/{\alpha}-Al_2O_3$ 촉매를 증착-침전법(deposition-precipitation)으로 제조하였다. 용액의 pH와 aging 시간에 따른 Ru 입자의 크기 변화와 분산도의 영향을 살펴보았으며 함침법(impregnation)으로 비교 촉매를 제조하였다. 촉매의 특성분석은 BET, TPR, CO-Chemisorption분석을 수행하여 촉매의 비표면적, 환원특성, 분산도를 알 수 있었다. 특성분석결과, 증착-침전법으로 제조한 $Ru/{\alpha}-Al_2O_3$ 촉매가 함침법으로 제조한 촉매에 비해 분산도가 높았으며, pH별 촉매 제조에서는 pH6.5로 제조한 촉매가 22.06%로 가장 높은 분산도를 보였다. 또한, 담체의 비표면적 영향에 따른 Ru 입자의 분산도를 살펴보기 위해 ${\gamma}-Al_2O_3$와 ${\alpha}-Al_2O_3$ 담체를 적용한 결과, 비표면적이 작은 ${\alpha}-Al_2O_3$ 담체 표면에서 Ru 분산도가 ${\gamma}-Al_2O_3$ 담체에 비해 높았다. 이는 기공이 발달하여 비표면적이 넓은 ${\gamma}-Al_2O_3$ 담체는 소량의 Ru을 고분산 담지 시 담체 표면보다는 기공 내에 담지 되는 양이 많아 실제 반응 시 반응에 참여하는 표면 활성 금속양이 적음을 알 수 있다. 특히, 선택적 산화반응과 같이 표면에서 빠른 반응이 일어나는 경우, 기공 내부의 활성금속이 반응에 참여하기 어려워 반응 활성이 낮음을 PrOx 반응실험을 통해 확인할 수 있었다. PrOx test 조건은 GHSV 250000~60000, 온도는 80~200도, 람다값은 2~4로 성능 비교하여 실험 하였다. PrOx의 성능평가 결과 담체를 ${\alpha}-Al_2O_3$를 사용하여 deposition-precipitation방법으로 제조한 pH6.5 촉매에서 $100{\sim}160^{\circ}C$에서 90%의 가장 높은 CO conversion을 가지고 18%의 선택도를 가졌다.