• Proceedings of the Korea Water Resources Association Conference
• /
• 2017.05a
• /
• pp.404-404
• /
• 2017

이상기후현상으로 인해 극치 수문 사상들이 빈번히 발생함에 따라 상대적으로 높은 재현기간에 해당하는 극치 수문 사상해석에 대한 관심이 높아지고 있다. 그러나 우리나라의 경우 이러한 극치 수문 사상을 추정하기 위한 표본의 수가 부족한 실정이다. 지역빈도해석은 지점의 표본 수가 적거나 수문자료의 수집이 불가능한 미계측지점인 경우, 해당 지점과 수문학적으로 동질하다고 여겨지는 주변 지점들의 자료를 확보하여 확률수문량을 추정함으로써 상대적으로 지점빈도해석 보다 roubst한 추정값을 얻을 수 있다는 장점을 가지고 있다. 따라서 최근 확률수문량 산정 기법으로 지역빈도해석 방법에 관한 관심이 높아지고 있다. 지역구분은 지역빈도해석이 지점빈도해석과 구분될 수 있는 큰 특징이고 지역구분 결과 따라 지역의 표본 크기가 결정되기 때문에 수문학적으로 동질한 지역을 나누는 방법은 매우 중요하다고 볼 수 있다. 인공신경망은 인간의 뇌가 학습하는 방식을 모사한 통계적 모델링 기법이다. 즉, 인간의 뇌가 일정한 반복 학습을 통해 어떠한 문제의 해법을 추론하거나 예측, 또는 패턴을 인식하는 일련의 과정을 알고리즘화 하여 목적함수의 해를 찾는 방식이다. 특히, 주어진 자료들로 부터 특징을 추출하고 그 특징을 학습하여 전체 자료의 분류나 군집화를 이루는데 널리 이용되고 있다. 본 연구에서는 낙동강유역을 대상으로 인공신경망을 이용한 군집분석을 수행하고 구분된 지역을 이용하여 지역빈도해석을 수행하였다.

• The KIPS Transactions:PartB
• /
• v.13B no.4 s.107
• /
• pp.393-400
• /
• 2006

There are many feature extraction methods for face recognition. We need a new method to overcome the small sample problem that the number of feature variables is larger than the sample size for face image data. The paper considers partial least squares(PLS) as a new dimension reduction technique for feature vector. Principal Component Analysis(PCA), a conventional dimension reduction method, selects the components with maximum variability, irrespective of the class information. So, PCA does not necessarily extract features that are important for the discrimination of classes. PLS, on the other hand, constructs the components so that the correlation between the class variable and themselves is maximized. Therefore PLS components are more predictive than PCA components in classification. The experimental results on Manchester and ORL databases shows that PLS is to be preferred over PCA when classification is the goal and dimension reduction is needed.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.20 no.1
• /
• pp.55-61
• /
• 2017

This study conducted a survey to evaluate the disaster response capability of coastal residents and analyzed the characteristics. For the sampling process, nonrandom sampling method was used. Sample size is 4,520 and sample error is ${\pm}1.5%p$ at 95% confidence level. As a result of the survey, 72% and 68% of the respondents said that they recognized the emergency contact network and listened to the disaster broadcast. On the other hand, 17% and 18% said that they organized the local voluntary disaster prevention teams and participated in disaster preparedness training. In addition, male's disaster response capability was higher than female's, and first aid techniques and participation in disaster preparedness training were higher in teens and twenties. By occupation, public official possess the highest response capability. By region, it was high in the East coast and low in the South coast. It is necessary that the authorities improve the national disaster preparedness training and publicity to enhance the coastal disaster response capability of coastal residents.

• The Journal of the Korea Contents Association
• /
• v.12 no.11
• /
• pp.145-154
• /
• 2012

The major purpose of this study is to examine how the support for dance education of dance majors affects the instructor' trust and dance attachment. This research was executed as the subjects who are currently the student of dance majors of a college in Seoul, Kyonggi, Daejeon and Chungchungnam-do, one college were selected from each district. And by using purposive sampling method, total of 262 peoples that were used in final analysis was extracted. In this study, adequacy and reliability of the questionnaire were verified by factor analysis, reliability analysis, regression analysis and course analysis by using SPSS18.0. The conclusion is as follows. First, instructor's support for dance education influences on instructor' trust. Secondly, support for dance education partly influences on dance attachment. Thirdly, instructor' trust influences on dance attachment. Lastly, support for dance education influences dance attachment throughout instructor' trust. Especially, support for dance education' influence for dance attachment throughout instructor' trust is more influential than support for dance education' influence for dance attachment directly. Now it is obvious that instructor' trust is the important variable that intermediate support for dance education and dance attachment.

• Journal of Korean Society for Quality Management
• /
• v.13 no.1
• /
• pp.77-83
• /
• 1985

This paper deals with a normality test to determine whether the data are sampled from normal population or not. In this paper the property that the mean and variance are independently distributed only for the normal distribution is used as a basis for developing a new test using the simple regression analysis. Considering the redan and variance of a random sample as independent and dependent variables, if it has not the regression relationship we conclude that the data were sampled from the normal distribution. The Monte-Carlo power study shows that the new test using the simple regression analysis has good power property relative to 6 well-known test methods for 11 distributions.

• Proceedings of the Korean Association for Survey Research Conference
• /
• 2002.06a
• /
• pp.137-156
• /
• 2002

인터넷 조사는 전통적인 조사방법에 비해 신속하고 저렴하며 멀티미디어를 이용한 고도화된 설문을 사용할 수 있다는 장점이 있는 반면 표본을 확률 추출하는 것이 어렵고, 대표성, 무응답 등의 비표본 오차가 심각하다. 본 연구에서는 비표본 오차 중 무응답 오차를 사례와 함께 정리하고, 인터넷 조사가 새로운 조사 방법으로서 활용될 수 있는 대안을 제시한다.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.44 no.2 s.314
• /
• pp.12-18
• /
• 2007

The three dimensional interpolation is widely used for many kinds of color signal transformation such as real-time color gamut mapping. Given input color signal, the output color signal is approximately calculated by the interpolation with the input point and extracted values from a lookup table which is constructed by storing the values of transformation at regularly packed sample points. Apparently, errors of the interpolated approximation heavily depend on the selection of the lookup table. In this paper, a least square method is applied to assigning values of the lookup table with fixed size in order to minimize error of three-dimensional interpolation. The experimental result shows that the proposed method has better interpolation performance.

• The Korean Journal of Applied Statistics
• /
• v.26 no.6
• /
• pp.933-942
• /
• 2013

Common factor analysis and principal component analysis represent two technically distinctive approaches to exploratory factor analysis. Much of the psychometric literature recommends the use of common factor analysis instead of principal component analysis. Nonetheless, factor analysts use principal component analysis more frequently because they believe that principal component analysis could yield (relatively) less accurate estimates of factor loadings compared to common factor analysis but most often produce similar pattern of factor loadings, leading to essentially the same factor interpretations. A simulation study is conducted to evaluate the relative performance of these two approaches in terms of factor pattern recovery under different experimental conditions of sample size, overdetermination, and communality.The results show that principal component analysis performs better in factor recovery with small sample sizes (below 200). It was further shown that this tendency is more prominent when there are a small number of variables per factor. The present results are of practical use for factor analysts in the field of marketing and the social sciences.

• Survey Research
• /
• v.10 no.1
• /
• pp.33-56
• /
• 2009

Landline telephone surveys of the population of households or individuals in Korea often use telephone directories as sampling frames. Recently, the frequency of unlisted numbers in the directories has been increased and the number of households without landline phones has become larger with a spread of mobile phones. Landline telephone coverage has currently reached to a level that raises concerns about the currently due to a coverage bias on the statistics in question. In this paper, we first present the distribution of telephone ownership in Korea and make a comparison with some selected countries. Second, we describe the characteristics of telephone directories. Next, we directly or indirectly estimate the telephone coverage rates of the frames, and show that it may nationally be lower than 65.6% based on additional information. We conclude with remarks about future studies to reduce coverage bias, including the developments of efficient random digit dialing sampling methods.

• Korean Security Journal
• /
• no.37
• /
• pp.109-135
• /
• 2013

The purpose of the study was to analyze how organizational learning of police officers affects empowerment components as this learning method works as a way to maximize the police organization. In order to achieve the research goal, the study selected a total of 170 police officers on duty in Gwangju Metropolitan Police Agency as a research subject for a month from July 14, 2013 to August 15. The subjects were selected via the random sampling method and were told to participate in a survey of a self-administrated method. A total of 163 (95.5%) references were used for the final analysis. The collected data was processed with SPSS for Win Version 18.0 and the variables were went through Pearson's Correlation Analysis and Multiple Regression Analysis. The results are summarized as follows. First, a hypothesis of "how social demographic characteristics have a different influence on organizational learning and empowerment" was partially confirmed. Second, another hypothesis of "how organizational learning affects empowerment of the members" was adopted.