• 제목/요약/키워드: K-Mean

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임상적으로 진단된 수근관증후군 환자에서 F파 분석 (F-Wave Analysis in Patients with Clinically Diagnosed Carpal Tunnel Syndrome)

  • 김성희;유봉구;김광수;유경무
    • Annals of Clinical Neurophysiology
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    • 제4권2호
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    • pp.108-113
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    • 2002
  • Background and Objective : Carpal tunnel syndrome (CTS) is the most common mononeuropathy encountered in clinical practice. No single procedure or group of procedures has demonstrated adequate sensitivity. F-wave study in CTS is very rarely reported. To determine the diagnostic usefulness of new parameters of F-wave and comparative study of F-wave parameters of median and ulnar nerves in patients with CTS. Methods : F-wave responses of median and ulnar nerves were analyzed from 27 patients with clinically diagnosed CTS and 22 age and gender-matched normal control. Conventional F-wave parameters were studied. Also, the usefulness of new parameters such as mean and maximal ulnar-median F-wave latency differences, ulnar-median F-wave persistence and chronodispersion differences, median/ulnar F-wave amplitude ratio, and F-wave conduction velocity (FCV) using mean and maximal latency were assessed. Results : Compared with controls, median F-wave minimal, maximal and mean latencies, mean F-wave amplitude/M-wave amplitude, minimal, mean and maximal ulnar-median F-wave latency differences, and FCVs using minimal, maximal and mean latency were significant (P<0.05~0.001). Median F-wave minimal, maximal and mean latencies, mean ulnar-median F-wave latency difference, and FCVs using minimal, maximal and mean latency showed high sensitivity and specificity. Mean ulnar-median F-wave latency difference and FCVs using maximal and mean latency were new parameters. Conclusion : New F-wave parameter including mean ulnar- median F-wave latency difference and FCVs using maximal and mean latency may be a useful to assess the CTS. Also, median F-wave minimal, maximal and mean latencies, and FCV using minimal latency may be included in routine diagnostic tests in CTS.

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Relationship Between the Mean and Median in a Skewed Frequency Distribution

  • Shin, Mi-Young;Cho, Tae Kyoung
    • Communications for Statistical Applications and Methods
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    • 제11권3호
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    • pp.513-518
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    • 2004
  • The well-known mode-mean-median inequality for the unimodal population distribution does not always hold for the frequency distribution. But many elementary statistics text books just mention that the relative location of the mean and median can be used to determine whether a distribution is positively or negatively skewed. In this paper we introduce the method generating data that is positively skewed but mean

중소도시지역 비점오염물질의 유출 특성 (Runoff Characteristics of Nonpoint Pollutants Source in Urban Area)

  • 이건직;성진욱;박주현;조규수;박제철
    • 한국환경과학회지
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    • 제19권7호
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    • pp.819-827
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    • 2010
  • This study was conducted to investigate runoff characteristics of non-point pollutants source at the urban area in boeun area, Chungbuk Province. The monitoring site covering the watershed of $2.11\;km^2$ contains about 40.3 % of total watershed with the urban area. The monitoring was conducted with six events for five months and Event Mean Concentration(EMC) and Site Mean Concentration(SMC) of SS, BOD, CODMn, T-N, T-P were calculated on the result of the water quality parameters. As a result of the comparion between Arithmetic Mean Concentration and Event Mean Concentration, it showed that over all Event Mean Concentration was higher than Arithmetic Mean Concentration. And it showed that SS, BOD, T-P featured the first-flushing effect, showing relatively high concentration in early-stage storm event.

수종 근관형성방법에 따른 레진모형상의 근관형태의 변화 (EFFECTS OF DIFFERENT PREPARATION METHODS ON THE MORPHOLOGIC CHANGE OF SIMULATED ROOT CANALS IN RESIN BLOCK)

  • 박미희;홍찬의
    • Restorative Dentistry and Endodontics
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    • 제19권1호
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    • pp.85-96
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    • 1994
  • In this study, 24 curved resin blocks were prepared by one of the following four methods: 1) Conventional technique using K-flexo files 2) Step-back technique using K-flexo files 3) Crown-down technique using K-flexo files 4) Canal Master instrumentation using Canal Master Resin blocks were sectioned, photographed, and evaluated the mean centering ratio and the mean area of dentin removed before and after the instrumentation. The results were as follows : I. the mean centering ratio 1. In the level 1 and level 3, there was no significant difference in the mean centering ratio. 2. In the level 2, Step-back technique showed the worst mean centering ratio among the tested groups(p<0.001) and there was no significant difference between the other three groups. 3. In the level 4, Canal Master instrumentation and Step-back technique showed better mean centering ratio than the other two techniques(p<0.001) and there was no significant difference between the two techniques. II. the mean area of dentin removed 1. In the level l and level 3, there was no significant difference in the mean area of dentin removed. 2. In the level 2, Canal Master instrumentation removed less dentin than the other three techniques(P<0.01). 3. In the level 4, Crown-down technique removed less dentin than the other three techniques(P<0.05).

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Contrast Image Enhancement Using Multi-Histogram Equalization

  • Phanthuna, Nattapong;cheevasuwit, Fusak
    • International Journal of Advanced Culture Technology
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    • 제3권2호
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    • pp.161-170
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    • 2015
  • Mean separated histogram equalization in order to preserve the original mean brightness has been proposed. To provide the minimum mean brightness error after the histogram modification, the input image's histogram is successively divided by the factor of 2 until the mean brightness error is satisfied the defined threshold. Then each divided group or sub-histogram will be independently equalized based on the proportional input mean. To provide the overall minimum mean brightness error, each group will be controlled by adding some certain pixels from the adjacent grey level of the next group for giving its mean near by the corresponding the divided mean. However, it still exists some little error which will be put into the next adjacent group. By successive dividing the original histogram, we found that the absolute mean brightness error is gradually decreased when the number of group is increased. Therefore, the error threshold is assigned in order to automatically dividing the original histogram for obtaining the desired absolute mean brightness error (AMBE). This process will be applied to the color image by treating each color independently.

작물모형 평가를 위한 통계적 방법들에 대한 비교 (Comparison of Statistic Methods for Evaluating Crop Model Performance)

  • 김준환;이충근;손지영;최경진;윤영환
    • 한국농림기상학회지
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    • 제14권4호
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    • pp.269-276
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    • 2012
  • 작물모형 평가에 사용되거나 사용할 수 있는 9가지 지표를 소개하였으며 이들의 특징은 다음과 같다. efficiency of model (EF)와 index of agreement (d)은 dimension이 없고 관측수(n)에 의존적이지 않았으며, dimension에 대해서만 자유로운 것은 relative root mean square error (RRMSE), bias factor (Bf)와 accuracy factor (Af)이다. Root mean sqruar, mean error, mean absolute error들은 관측수와 dimension에 영향을 받기 때문에 판단 시 주의가 필요하다. 따라서 이들의 특징을 파악하여 목적에 맞게 모형의 성능을 파악하여야 한다.

Weighted Carlson Mean of Positive Definite Matrices

  • Lee, Hosoo
    • Kyungpook Mathematical Journal
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    • 제53권3호
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    • pp.479-495
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    • 2013
  • Taking the weighted geometric mean [11] on the cone of positive definite matrix, we propose an iterative mean algorithm involving weighted arithmetic and geometric means of $n$-positive definite matrices which is a weighted version of Carlson mean presented by Lee and Lim [13]. We show that each sequence of the weigthed Carlson iterative mean algorithm has a common limit and the common limit of satisfies weighted multidimensional versions of all properties like permutation symmetry, concavity, monotonicity, homogeneity, congruence invariancy, duality, mean inequalities.

Estimation of Geometric Mean for k Exponential Parameters Using a Probability Matching Prior

  • Kim, Hea-Jung;Kim, Dae Hwang
    • Communications for Statistical Applications and Methods
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    • 제10권1호
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    • pp.1-9
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    • 2003
  • In this article, we consider a Bayesian estimation method for the geometric mean of $textsc{k}$ exponential parameters, Using the Tibshirani's orthogonal parameterization, we suggest an invariant prior distribution of the $textsc{k}$ parameters. It is seen that the prior, probability matching prior, is better than the uniform prior in the sense of correct frequentist coverage probability of the posterior quantile. Then a weighted Monte Carlo method is developed to approximate the posterior distribution of the mean. The method is easily implemented and provides posterior mean and HPD(Highest Posterior Density) interval for the geometric mean. A simulation study is given to illustrates the efficiency of the method.

간호학생의 보건교육 수행정도와 간호전문직 만족도와의 관계연구 (The Relationship between Health Education Competency and Satisfaction of Professional Nursing in Nursing Students)

  • 주혜경
    • 한국간호교육학회지
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    • 제5권1호
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    • pp.106-117
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    • 1999
  • A study was conducted to identify the perceptions about health education competence and satisfaction of nursing profession, and the relationship between health education competency and satisfaction of nursing profession in nursing students. The subjects were 118 nursing students who were third year at a diploma course. The results of this study are as follows : 1) In domain of health education process, the highest level of competency was the need assessment of the individual health education(mean : 3.62) and the lowest level of competency was the evaluation of heath education program(mean : 2.93. 2) In domain of health education method, the level of competency was estimated ordered as counselling and interview (mean : 3.53), health campaign(mean : 3.42), demonstration(mean : 3.30), role play (mean : 3.28), group discussion (mean : 3.25), lecture(mean : 3.10). 3) In domain of health education place, the level of competency was estimated ordered as of patient education while giving individually care(mean : 3.68), at home(mean : 3.67), in the classrom(mean : 3.67), in the community(mean : 3.35), while teaching with group patients at hosital(mean : 3.30). 4) In domain of activities of health educator, the level of competency was ordered as collaborator(mean : 3.59), coordinator(mean : 3.31), material developer(mean 3.14), program evaluator(mean : 3.13), program designer(mean 3.10). 5) Health education competency was found to be significantly related to satisfaction of professional nursing.

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