• 제목/요약/키워드: Non-parametric statistical analysis

검색결과 94건 처리시간 0.03초

경포호에서 수질변수들의 장기적인 변화 (Long-term Variations of Water Quality Parameters in Lake Kyoungpo)

  • 곽성진;발데브;최광순;허우명
    • 생태와환경
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    • 제48권2호
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    • pp.95-107
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    • 2015
  • 경포호에서 수질 변수들의 장기적인 경향을 파악하기 위하여 1998년부터 2013년까지 매년 3월부터 11월까지 2개월에 1회씩 3개 지점에서 조사된 15가지 수질변수들과 강우량자료를 이용하였으며, Mann-Kendall test, Sen's slope estimator 및 linear regression을 적용 분석하였다. 계절 변화 분석에는 Mann-Kendall test 및 Sen's slope estimator만 이용하였다. 분석결과 염분, 투명도 및 영양염류 (총인, 용존무기인, 총질소, 질산성 질소, 암모니아성 질소)의 변수들만 통계학적으로 유의적인 경향을 보였다. 선형회귀 분석에서는 염분 (표층과 심층의 전 지점)과 투명도 (지점 1)만이 통계학적으로 유의적인 증가 경향을 나타냈으나, 비모수법에 의한 분석에서는 염분과 투명도 모두 전 지점에서 통계학적으로 유의적인 증가 경향을 보였다. 통계학적으로 유의적인 감소 경향을 보인 수질변수들은 선형회귀분석에서는 용존산소 (표층 지점 1, 심층 지점 2와 3), 총인(지점 1과 2), 용존무기인, 총질소, 질산성 질소 및 암모니아성 질소, 비모수법에 의한 분석에서는 용존산소 (심층 전지점), 총인, 용존무기인, 총질소, 질산성 질소 및 암모니아성 질소였다. 계절적인 경향을 분석한 결과 봄에는 염분, 탁도, 투명도 및 부유물질 (SS), 여름에는 염분, 투명도, 질산성 질소 및 부유물질, 가을에는 수온, 염분, 투명도 및 부유물질 만이 증가하는 경향을 보였으며 이들 변수들이 계절에 따라 다소 차이를 보이는 것으로 나타났다. 특히 봄과 여름에 비해서 가을철에 Mann-Kendall test 및 Sen's Slope estimator에 의해 유의적인 경향을 나타낸 수질변수들이 많았다. 가장 강한 증가 경향을 보인 것은 염분이었으며 봄보다는 여름과 가을에 뚜렷하였다. 투명도도 염분과 유사한 특성을 보였다. 강우량은 조사기간 동안 전체적으로 감소하는 경향을 보였다. 경포호에서 영양염류의 유의적인 감소경향은 그동안 강릉시에서 추진해온 석호 복원사업 및 해수유통 (수중 보철거) 등과 관련이 있는 것으로 판단되나 정확한 원인 규명을 위해서는 보다 면밀한 조사가 수반되어야 할 것으로 사료된다.

장기 조위자료를 이용한 한반도 권역별 미래 해수면 상승 추정 (Estimation of the Regional Future Sea Level Rise Using Long-term Tidal Data in the Korean Peninsula)

  • 이철응;김상욱;이영섭
    • 한국수자원학회논문집
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    • 제47권9호
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    • pp.753-766
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    • 2014
  • 본 논문에서는 기후변화로 인한 한반도 주요 권역에서의 미래 평균해수면 상승을 장기 조위자료를 사용하여 통계적으로 추정하는 연구를 수행하였다. 먼저 5개 조위 관측소로부터 얻어진 장기 조위자료에 대한 비모수적 경향성 검정인 Mann-Kendall 검정을 통해 관측된 자료의 경향성을 검정하였으며, 이를 보다 정량적으로 분석하기 위하여 Bayesian 변동점 분석 기법을 적용하였다. 특히 이 연구에서는 4개의 미래 평균해수면 상승 시나리오와 5개 관측소의 지역별 평균해수면 상승 자료를 결합시키기 위하여 변동점 분석결과를 활용하였다. 제안된 절차는 미래 평균해수면 상승 시나리오의 시작년도를 결정함에 있어 18.6년의 주기를 사용하지 않고 변동점 분석결과를 사용함으로써, 지역적 특성을 효과적으로 반영할 수 있도록 개선되었다. 변동점 분석결과를 사용하여 한반도의 권역별 미래 해수면상승을 분석한 결과, 제주 권역(제주 조위관측소)이 가장 뚜렷한 해수면 상승을 나타냈다. 서해안 권역(보령 조위관측소)과 남해안 권역(부산 조위관측소)에서는 두 번째로 높은 해수면 상승의 증가가 추정되었으며, 마지막으로 남해안 권역(여수 조위관측소)와 동해안 권역(속초 조위관측소)에서 가장 낮은 해수면 상승의 증가가 추정되었다.

Investigation of light stimulated mouse brain activation in high magnetic field fMRI using image segmentation methods

  • Kim, Wook;Woo, Sang-Keun;Kang, Joo Hyun;Lim, Sang Moo
    • 한국컴퓨터정보학회논문지
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    • 제21권12호
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    • pp.11-18
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    • 2016
  • Magnetic resonance image (MRI) is widely used in brain research field and medical image. Especially, non-invasive brain activation acquired image technique, which is functional magnetic resonance image (fMRI) is used in brain study. In this study, we investigate brain activation occurred by LED light stimulation. For investigate of brain activation in experimental small animal, we used high magnetic field 9.4T MRI. Experimental small animal is Balb/c mouse, method of fMRI is using echo planar image (EPI). EPI method spend more less time than any other MRI method. For this reason, however, EPI data has low contrast. Due to the low contrast, image pre-processing is very hard and inaccuracy. In this study, we planned the study protocol, which is called block design in fMRI research field. The block designed has 8 LED light stimulation session and 8 rest session. All block is consist of 6 EPI images and acquired 1 slice of EPI image is 16 second. During the light session, we occurred LED light stimulation for 1 minutes 36 seconds. During the rest session, we do not occurred light stimulation and remain the light off state for 1 minutes 36 seconds. This session repeat the all over the EPI scan time, so the total spend time of EPI scan has almost 26 minutes. After acquired EPI data, we performed the analysis of this image data. In this study, we analysis of EPI data using statistical parametric map (SPM) software and performed image pre-processing such as realignment, co-registration, normalization, smoothing of EPI data. The pre-processing of fMRI data have to segmented using this software. However this method has 3 different method which is Gaussian nonparametric, warped modulate, and tissue probability map. In this study we performed the this 3 different method and compared how they can change the result of fMRI analysis results. The result of this study show that LED light stimulation was activate superior colliculus region in mouse brain. And the most higher activated value of segmentation method was using tissue probability map. this study may help to improve brain activation study using EPI and SPM analysis.

大韓眼耳鼻咽喉皮膚科學會誌에 揭載된 硏究論文들의 傾向性 考察 (The Study on the Trends of Resecarch Papers Published in the Journal of Oriental Medical Surgery?phthalmology & Otolaryngology Society.)

  • 권강;서형식
    • 한방안이비인후피부과학회지
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    • 제16권1호
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    • pp.1-32
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    • 2003
  • Objectives: This study was carried out to analyze and understand the trends of research papers published In the Journal of Oriental Medical Surgery?phthalmology & Otolaryngology Society(JOMSOOS). Methods: We studied the 308 research papers that had been published in JOMSOOS from 1988 Vol. 1. No. 1. to 2002 Vol. 15. No. 2. Our study was developed through the four stages in order to analyze the papers; 1) we analyzed all the papers overall to classify them into three categories; original article. review article and case report. 2) we classified the original articles in terms of methodology. 3) we also analyzed the case reports according to the sort of disease each paper dealt with. 4) we had another statistical approach to each paper to figure out the distribution of diagnoses in detail. Results: We have got the following outcomes from our analysis of the papers in terms of the four stages. 1. Overall Analysis. 1) Classification of 308 research papers between 1988 and 2002: 137 original articles(44.48$\%$), 111 review articles(36.04$\%$), 56 case reports(18.18$\%$). 2) Used language: Korean(99.03$\%$). English(0.97$\%$). 3) The Number of Authors: 2 persons(42.86$\%$). 3 persons(29.87$\%$), 1 person(14.61$\%$). 2. Original Article Analysis 1) Classification of 137 original articles in terms of methodology: 90 experimental studies(65.69$\%$)46 descriptive studies(33.58$\%$), 1 analytic study(0.73$\%$). 2) Classification of the original articles according to the use of statistical methods: No statistical methods(36.42$\%$), Descriptive methods only(1.99$\%$), Not defined(23.18$\%$), t-test(24.50$\%$), ANOVA(3.97$\%$), Multiple comparison(2.65$\%$), Non-parametric test(2.65$\%$), Other methods(1.32$\%$). 3) Classification of 46 descriptive articles in terms of diseases: otorhinolaryngology(43.48$\%$), dermatology(23.91$\%$), ophthalmology(13.04$\%$), facial palsy(13.04$\%$). 4) Classification of descriptive articles in terms of the number of patients: the highest was 'more than 26 but less than 50 persons'(19 articles - 41.30$\%$). 5) Classification of descriptive articles in terms of the period for patients observation: the highest was the time 'more than 9 but less than 12 months(34.78$\%$)' Out of the 34.78$\%$, the number of articles with the patients observed for more than 12 months was 13(28.26$\%$). 3. Case Report Analysis 1) Classification of 56 case reports in terms of the sort of disease: dermatology(44.64$\%$), ophthalmology(19.64$\%$), otorhinolaryngology(14.29$\%$), facial palsy(8.93$\%$). 2) Classification in terms of the number of patients: 1 person(50$\%$), 3 persons(16.07$\%$), 2 persons(14.29$\%$). 4. Diagnosis Distribution of Each Disease. 1) Studies regarding ophthalmology : the percentage of 'strabismus' cases was the highest(33.33$\%$). 2) Studies regarding otorhinolaryngology : nasal inflammation(34.48$\%$), tinnitus(20.69$\%$). 3) Studies regarding dermatology: the percentage of 'allergic skin disease' was the highest(33.33$\%$). Conclusions: We analyzed the trends of research papers that have been published in JOMSOOS in detail. We came to understand the trends of the research through this study. However, we acknowledge that we only adopted the quantitative method out of various possible analysis methods. For further studies, we strongly urge to adopt the qualitative methods as well.

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확률 뇌 지도를 이용한 뇌 영역의 위치 정보 추출 (Probabilistic Anatomical Labeling of Brain Structures Using Statistical Probabilistic Anatomical Maps)

  • 김진수;이동수;이병일;이재성;신희원;정준기;이명철
    • 대한핵의학회지
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    • 제36권6호
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    • pp.317-324
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    • 2002
  • 목적: SPM 기법을 이용하여 뇌 영상을 분석할 때 Talairach 뇌 지도를 찾아 해부학적 정보를 추측함으로 생기는 문제점들을 해결하기 위하여 통계적 확률 뇌지도(SPAM)을 이용하여 뇌 영역에 대한 해부학적 위치와 확률을 추출하는 프로그램을 개발하였다. 대상 및 방법: 몬트리얼 신경과학연구소에서 개발한 MNI152 표준지도에 기반한 SPAM을 이용하였다. SPM 분석 결과로 주어진 x, y, z 좌표 값을 입력하면 SPAM의 해당 좌표에서 0이 아닌 확률 값을 갖는 영역의 이름 및 확률을 추출하여 출력하게 하였으며 가장 높은 확률을 갖는 영역의 SPAM을 표준지도 위에 표시하도록 하였다. IDL 및 자바를 기반으로 프로그램을 개발하였으며 향후 인터넷 기반 프로그램으로 확장이 용이하게 하였다. 이 프로그램의 유용성을 보이고자 기존의 SPM 결과보고 형식과 이 프로그램의 결과 형식을 비교하였다. 또한 이 프로그램에 대한 예비적인 검증을 위하여 활성화되는 영역이 국소화되고 또한 그 영역이 잘 알려져 있는 기억 활성화 PET 실험 분석에 이 프로그램을 이용하여 보았다. 결과: 기존의 SPM 분석한 결과는 MNI 좌표계에서의 좌표 값만을 보여주나 이 프로그램을 이용하여 그 좌표에 대한 확률적 해부학적 정보를 얻을 수 있었다. 기억 실험 결과 유의한 활성화를 보인 영역에 대해서 이 프로그램을 적용한 결과 좌측해마구성체일 확률이 80% 이상임을 알 수 있었으며 이는 이 영역이 기억기능을 담당한다는 기존의 널리 알려진 사실과 잘 부합되었다. 결론: 이 연구에서 개발한 프로그램을 이용하여 MNI 좌표에 대한 해부학적 위치와 확률을 빠르고 정확하게 찾을 수 있어서 뇌영상 분석에 유용할 것이다.

다분류 SVM을 이용한 DEA기반 벤처기업 효율성등급 예측모형 (The Prediction of DEA based Efficiency Rating for Venture Business Using Multi-class SVM)

  • 박지영;홍태호
    • Asia pacific journal of information systems
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    • 제19권2호
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    • pp.139-155
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    • 2009
  • For the last few decades, many studies have tried to explore and unveil venture companies' success factors and unique features in order to identify the sources of such companies' competitive advantages over their rivals. Such venture companies have shown tendency to give high returns for investors generally making the best use of information technology. For this reason, many venture companies are keen on attracting avid investors' attention. Investors generally make their investment decisions by carefully examining the evaluation criteria of the alternatives. To them, credit rating information provided by international rating agencies, such as Standard and Poor's, Moody's and Fitch is crucial source as to such pivotal concerns as companies stability, growth, and risk status. But these types of information are generated only for the companies issuing corporate bonds, not venture companies. Therefore, this study proposes a method for evaluating venture businesses by presenting our recent empirical results using financial data of Korean venture companies listed on KOSDAQ in Korea exchange. In addition, this paper used multi-class SVM for the prediction of DEA-based efficiency rating for venture businesses, which was derived from our proposed method. Our approach sheds light on ways to locate efficient companies generating high level of profits. Above all, in determining effective ways to evaluate a venture firm's efficiency, it is important to understand the major contributing factors of such efficiency. Therefore, this paper is constructed on the basis of following two ideas to classify which companies are more efficient venture companies: i) making DEA based multi-class rating for sample companies and ii) developing multi-class SVM-based efficiency prediction model for classifying all companies. First, the Data Envelopment Analysis(DEA) is a non-parametric multiple input-output efficiency technique that measures the relative efficiency of decision making units(DMUs) using a linear programming based model. It is non-parametric because it requires no assumption on the shape or parameters of the underlying production function. DEA has been already widely applied for evaluating the relative efficiency of DMUs. Recently, a number of DEA based studies have evaluated the efficiency of various types of companies, such as internet companies and venture companies. It has been also applied to corporate credit ratings. In this study we utilized DEA for sorting venture companies by efficiency based ratings. The Support Vector Machine(SVM), on the other hand, is a popular technique for solving data classification problems. In this paper, we employed SVM to classify the efficiency ratings in IT venture companies according to the results of DEA. The SVM method was first developed by Vapnik (1995). As one of many machine learning techniques, SVM is based on a statistical theory. Thus far, the method has shown good performances especially in generalizing capacity in classification tasks, resulting in numerous applications in many areas of business, SVM is basically the algorithm that finds the maximum margin hyperplane, which is the maximum separation between classes. According to this method, support vectors are the closest to the maximum margin hyperplane. If it is impossible to classify, we can use the kernel function. In the case of nonlinear class boundaries, we can transform the inputs into a high-dimensional feature space, This is the original input space and is mapped into a high-dimensional dot-product space. Many studies applied SVM to the prediction of bankruptcy, the forecast a financial time series, and the problem of estimating credit rating, In this study we employed SVM for developing data mining-based efficiency prediction model. We used the Gaussian radial function as a kernel function of SVM. In multi-class SVM, we adopted one-against-one approach between binary classification method and two all-together methods, proposed by Weston and Watkins(1999) and Crammer and Singer(2000), respectively. In this research, we used corporate information of 154 companies listed on KOSDAQ market in Korea exchange. We obtained companies' financial information of 2005 from the KIS(Korea Information Service, Inc.). Using this data, we made multi-class rating with DEA efficiency and built multi-class prediction model based data mining. Among three manners of multi-classification, the hit ratio of the Weston and Watkins method is the best in the test data set. In multi classification problems as efficiency ratings of venture business, it is very useful for investors to know the class with errors, one class difference, when it is difficult to find out the accurate class in the actual market. So we presented accuracy results within 1-class errors, and the Weston and Watkins method showed 85.7% accuracy in our test samples. We conclude that the DEA based multi-class approach in venture business generates more information than the binary classification problem, notwithstanding its efficiency level. We believe this model can help investors in decision making as it provides a reliably tool to evaluate venture companies in the financial domain. For the future research, we perceive the need to enhance such areas as the variable selection process, the parameter selection of kernel function, the generalization, and the sample size of multi-class.

$^{99m}Tc-HMPAO$ 뇌 SPECT에서 시각자극에 의한 국소 뇌 혈류변화의 정량적 검증 (Quantitative Evaluation of Regional Cerebral Blood Flow by Visual Stimulation in $^{99m}Tc-HMPAO$ Brain SPECT)

  • 주라형;서태석;곽철은;최보영;이형구;정용안;김성훈;정수교
    • 대한핵의학회지
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    • 제36권3호
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    • pp.166-176
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    • 2002
  • 목적: 이 연구의 목적은 시각 활성 자극에 의한 뇌 활성영역을 확인하고 국소 뇌 혈류량을 정량적으로 분석하는데 그 목적이 있다. $^8F-fluoro-2-deoxy\;glucose\;(FDG)\;PET$$^{15}O-water\;PET$에서 시각 자극을 가하는 동안 시각피질에서의 기전이 확인되었으며 PET에 비해 적은 비용으로 널리 사용되고 있는 $^{99m}Tc-HMPAO$ Brain SPECT를 이용하여 시각자극을 주었을 때 대뇌 후두엽의 일차시각피질과 시각 연합 피질에서의 국소 뇌 혈류 변화율을 정량적으로 분석하고자 하였다. 대상 및 방법: 오른손을 주로 사용하는 25세에서 33세의 나이 분포를 갖는 남자 3, 여자 3명(평균나이 26.7세)의 정상인을 대상으로 $^{99m}Tc-HMPAO$ Brain SPECT (925 MBq)를 시행하였고 8 Hz의 발광다이오드를 이용하여 $4{\sim}5$분 동안 시각활성 자극을 주었을 때와 대조군으로 자극을 가하지 않은 비 활성상태에서의 경우로 나누어 스캔하고 해부학적 기준정보를 제공하기 위해 MR 영상과 융합하였으며 관심영역을 설정하여 혈류량을 정량적으로 분석하였다. 결과: 정량적인 분석을 위해 대뇌의 전체 용적과 계수율을 계산하고 관심 영역을 설정하여 관심영역에 대한 복셀 당 평균 계수율을 측정하여 각 대상의 시각 활성자극을 가한 영상에서 정상 상태의 영상을 픽셀 당 픽셀로 감산하여 통계적 파라미터를 이용한 뇌 지도를 구성하였으며 뇌 활성이 Brodmann 영역의 시각피질(Ba 17)과 시각연합피질(Ba 18,19)에서 활성화되어 있음을 Talairach 좌표를 통해 확인하였고 regional index를 계산하여 국소 뇌혈류 변화율을 측정하였다. 결론: $^{99m}Tc-HMPAO$ Brain SPECT에서 8 Hz의 발광 다이오드로 시각 자극을 주었을 때 후두엽의 일차 시각피질과 시각 연합 피질에서 뇌 활성화를 확인하였고 통계적 파라미터를 이용한 SPM99에서 뇌 지도를 작성하여 시각자극에 의한 활성영역을 Talairach 좌표와 Brodmann 분류에 의해 확인하여 T1 강조 MR 영상에 융합하였다. 후두엽의 일차시각피질에서 시각 활성자극에 의해 국소 뇌 혈류량이 $32.50{\pm}5.67%$ 증가하고 있음을 정량적으로 분석하였다.

뇌혈관 질환 환자 사정에 대한 의료인간의 일치도 및 가정간호사업 대상자 선정에 관한 연구 (A Study on Client Selection Criteria for Home Health Care in Patients with Cerebral Vascular Disease)

  • 추수경;정복례
    • 한국보건간호학회지
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    • 제7권2호
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    • pp.39-52
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    • 1993
  • The primary purpose of this study is to promote and establish the development of home health care in Korea. It focuses on identifying and classifying the nursing activities that were provided by health professionals for patients who were admitted to two hospitals with cerebral vascular disease. And also. the study was conducted for comparison of client selection criteria between health professionals, and identifying patients who needed home health care The subjects of this study were 38 patients with cerebral vascular disease who were admitted to neuro-surgery wards at 2 hospitals with more than 500 beds in Daegu from November 1. through 30. 1991. Survey instruments were questionnaires to identify nursing activities and classify patients who needed home health care. Data was collelected by 1 doctor and 2 nurses per patient independently. They checked the same patient with the questionnaire on the same day and never communicated their information about patients with each other. All the questionnaires checked by doctor and nurses completely were 90. Statistical methods for analyzing data were non-parametric tests (Kruskal Wallice test and sign test). Correlation and percentages were used for further analysis. From this study. the following summarized conclusions have been drawn. 1. 10. 2 kinds of treatment and nursing activities were provided by health professionals for patients with cerebral vascular disease in hospital. 2. The points of nursing needs were between 32-37 out of a total of 500 as a result of the assessment about the health status of patients who were admitted to neuro-surgery ward with cerebral vascular disease. The points of Barthel Index of Functional Status Assessing Devices were between 24-34. Client Selection Criteria for Home Health Care was congruent between the Health professionals because the difference were not found to be statistically significant. 3. Patients classfied as home health care clients were $70-80\%$ of all patients who were admitted in hospital. There was not significant difference in patient selection criteria for home health care between health professionals statistically. As a result. the validity of different tools used in classifying home health care client were found to be congruent. 4. $80-85\%$ patients who could be discharged and sent to their homes early were identified as home health care clients. This study using client selection criteria. for home health care contributed to tool development because the validity of tools was verified. And also, this research represented that there was congruency in patient selection criteria for home health care between different health professionals. As a result, this study represented that many patients who were admitted to hospitals could be classified as a home health care clients. On the basis of the findings. further studies are required to develop client selection criteria using universal tools for classifying home health care clients in other chronic diseases. It is also recommended that comparative studies for client selection criteria between health professionals treating in other chronic diseases are necessary.

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글로벌 금융위기 이후 한국 주식유통시장의 위험가격에 관한 연구 (The Price of Risk in the Korean Stock Distribution Market after the Global Financial Crisis)

  • 손경우;유원석
    • 유통과학연구
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    • 제13권5호
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    • pp.71-82
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    • 2015
  • Purpose - The purpose of this study is to investigate risk price implied from the pricing kernel of Korean stock distribution market. Recently, it is considered that the quantitative easing programs of major developed countries are contributing to a reduction in global uncertainty caused by the 2007~2009 financial crisis. If true, the risk premium as compensation for global systemic risk or economic uncertainty should show a decrease. We examine whether the risk price in the Korean stock distribution market has declined in recent years, and attempt to provide practical implications for investors to manage their portfolios more efficiently, as well as academic implications. Research design, data and methodology - To estimate the risk price, we adopt a non-parametric method; the minimum norm pricing kernel method under the LOP (Law of One Price) constraint. For the estimation, we use 17 industry sorted portfolios provided by the KRX (Korea Exchange). Additionally, the monthly returns of the 17 industry sorted portfolios, from July 2000 to June 2014, are utilized as data samples. We set 120 months (10 years) as the estimation window, and estimate the risk prices from July 2010 to June 2014 by month. Moreover, we analyze correlation between any of the two industry portfolios within the 17 industry portfolios to suggest further economic implications of the risk price we estimate. Results - According to our results, the risk price in the Korean stock distribution market shows a decline over the period of July 2010 to June 2014 with statistical significance. During the period of the declining risk price, the average correlation level between any of the two industry portfolios also shows a decrease, whereas the standard deviation of the average correlation shows an increase. The results imply that the amount of systematic risk in the Korea stock distribution market has decreased, whereas the amount of industry-specific risk has increased. It is one of the well known empirical results that correlation and uncertainty are positively correlated, therefore, the declining correlation may be the result of decreased global economic uncertainty. Meanwhile, less asset correlation enables investors to build portfolios with less systematic risk, therefore the investors require lower risk premiums for the efficient portfolio, resulting in the declining risk price. Conclusions - Our results may provide evidence of reduction in global systemic risk or economic uncertainty in the Korean stock distribution market. However, to defend the argument, further analysis should be done. For instance, the change of global uncertainty could be measured with funding costs in the global money market; subsequently, the relation between global uncertainty and the price of risk might be directly observable. In addition, as time goes by, observations of the risk price could be extended, enabling us to confirm the relation between the global uncertainty and the effect of quantitative easing. These topics are beyond our scope here, therefore we reserve them for future research.

개인보호구 실습교육의 반복학습 효과와 만족도에 미치는 영향 (Effects of Personal Protective Equipment Practice Education on the Effectiveness of Repeated Learning and Satisfaction )

  • 조대진;어원석
    • 한국산업보건학회지
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    • 제33권2호
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    • pp.156-170
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    • 2023
  • Objectives: This study conducted practical training to improve the proper usage of personal protective equipment(PPE), which greatly impacts workplace safety and health management. Personal protective equipment education was conducted through active participation, without theoretical modules, and aimed to identify the effects of repeated practical education and determine ways to increase participant satisfaction. Methods: Study data were analyzed using the IBM SPSS Statistics ver.29 software. First, participants' general characteristics were analyzed with frequency analysis. Second, the normality and equality of variances (Leven's test) were tested for the dependent variables prior to statistical analyses to determine the use of parametric tests. In general, normality is assumed when the sample size is 30 or more per the central limit theorem (Park et al., 2014). As our sample size of health management workers was 43, normality can be assumed. However, to ensure rigor of the study, we examined skewness and kurtosis. The results confirmed that the data were normally distributed. Third, the effects of repeated PPE training were analyzed using paired t-tests. Fourth, differences in satisfaction with PPE training according to the safety and health job position and safety and health certification were analyzed with t-test and Welch's t-test. For parameters that did not meet the assumption of equal variances, the Welch's t-test was performed. Results: Repeated PPE training improved the educational outcomes, and the improvements were significant in the 1st and 2nd respiratory PPE and safety and hygiene PPE training evaluations (p<.001). In terms of safety and health job position, repeated training led to improvements in educational outcomes, with significant improvements observed among supervisors and specialized health management institution workers in the 1st and 2nd training evaluations (p<.005). In terms of safety certification, repeated training led to improvements in educational outcomes, with significant improvements observed among both certified and non-certified individuals (p<.005). Regarding satisfaction with PPE training according to safety and health job positions, specialized health management institution workers showed greater satisfaction than supervisors, with significant differences in the satisfaction for expertise of lecture, work relevance, and lecturer's attitude (p<.001). Regarding satisfaction with PPE training according to safety and health certification, satisfaction was higher among certified individuals, with significant differences in satisfaction for work relevance and lecture attitude (p<.05) Conclusions: PPE education should be recommended to be provided as practical training. Repeated training can enhance educational outcomes for individuals with inadequate knowledge and understanding of PPE prior to education. For individuals with high levels of pre-existing knowledge and understanding of PPE, the results show that various training experiences should be provided to enhance their satisfaction. Therefore, it suggests that the workplace should actively seek educational media and methods to acquire expertise and skills in wearing personal protective equipment and improve the ability to use