• Title/Summary/Keyword: distributional analysis

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Distributional Patterns of Understory Vegetation at Mt. Geumdae's Protected Area for Forest Genetic Resources (금대봉 산림유전자원보호림의 하층식생 분포양상)

  • Chun, Seung-Hoon;Lee, Hyung-Sook;Lim, Jong-Hwan
    • Journal of Korean Society of Forest Science
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    • v.98 no.3
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    • pp.339-350
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    • 2009
  • This study was carried out to investigate distributional condition of rare plants and useful plant resources, and to verify distributional patterns of understory vegetation associated with the upper layer's vegetation structure. Total 59 families, 160 genera, 218 kinds of vascular plants were identified at the study site including 6 rare plants designated by Korea Forest Service (Lloydia triflora Bak., Trillium kamtschaticum Pall., Lilium distichum Nakai, Anemone koraiensis Nakai, Iris odaesanensis Y.N. Lee, Viola diamantica Nakai). Twenty three species of useful plant resources were also identified at the site; 8 of them showed clustered distributions and the others were prone to scatter. Actual vegetation of this study area consisted of one natural community dominated by Quercus mongolica Fisch. and three disturbed communities of Larix kaempferi (Lamb.) Carriere, Abies holophylla Max. and/or a herbaceous vegetation resulting from forest removal and strong wind of mountain top. This classification was strongly supported by cluster analysis based on the surveyed plot data. Distributional patterns of understory vegetation within forest stand were somewhat related to overstory vegetation structure, but showed a different tendency according to site condition, species composition, and competitive pressure among understory vegetation. Therefore, in order to protect the important understory components as forest genetic resources, forest treatments such as density control of overstory should be implanted based on understanding of impact on understory's dynamics and growing condition.

Quantification of Entire Change of Distributions Based on Normalized Metric Distance for Use in PSAs

  • Han, Seok-Jung;Chun, Moon-Hyun;Tak, Nam-Il
    • Nuclear Engineering and Technology
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    • v.33 no.3
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    • pp.270-282
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    • 2001
  • A simple measure of uncertainty importance based on normalized metric distance to quantify the entire change of cumulative distribution functions (CDFs) has been developed for use in probability safety assessments (PSAs). The metric distance measure developed in this study reflects the relative impact of distributional changes of inputs on the change of an output distribution, white most of the existing uncertainty importance measures reflect the magnitude of relative contribution of input uncertainties to the output uncertainty. Normalization is made to make the metric distance measure a dimensionless quantity. The present measure has been evaluated analytically for various analytical distributions to examine its characteristics. To illustrate the applicability and strength of the present measure, two examples are provided. The first example is an application of the present measure to a typical problem of a system fault tree analysis and the second one is for a hypothetical non-linear model. Comparisons of the present result with those obtained by existing uncertainty importance measures show that the metric distance measure is a useful tool to express the measure of uncertainty importance in terms of the relative impact of distributional changes of inputs on the change of an output distribution.

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Distributional Characteristics of Coastal Mantle Communities in Korean Peninsula (한반도 해안임연군락의 분포특성)

  • Jung, Yong-Kyoo;Kim, Woen
    • The Korean Journal of Ecology
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    • v.23 no.3
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    • pp.193-199
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    • 2000
  • The research about distributional characteristics of coastal mantle communities in South Korea was accomplished. This study was carried out by direct analysis of the latitude and temperatures of each releve site on the basis of syntaxonomy and hierarchical system of coastal mantle communities which was already obtained from Zurich-Montpellier School's method. The distribution of coastal mantle communities in South Korea appeared from North to South in the order of Rosa rugosa community, Vitex rotundifolia community, the Linario-Viticetum rotundifoliae, the Roso-Viticetum rotundifoliae and the Imperato-Viticetum rotundifoliae, and it was recognized that tendencies of continuous and overlapped distribution pattern in adjacent syntaxa. Consequently, It is suggested that the syntaxonomical, geographical and bioclimatic informations of Japan, North Korea and China are essential to determine the distributional patterns of coastal mantle communities in Korean Peninsula.

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A Study on the Effects of Customers' Roles in the Service Recovery Process (서비스 실패와 회복과정에서 고객의 역할에 관한 연구)

  • Lee, Choong-Ryul;Ahn, Jinwoo
    • Management & Information Systems Review
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    • v.33 no.3
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    • pp.105-128
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    • 2014
  • This study attempted to examine the role of customers in service recovery process. There have been an argument regarding whether the role of customer in service failure situation 'buffer' or 'deteriorate'. Thus, the role of customer such as relationship quality and customer participation was discussed in this research. According to the result of study, (1) customers' perceived recovery have positive effect on positive emotion significantly. (2) customers' perceived distributional justice and interactional justice positively affected encounter satisfaction in the of recovery justice variable. However, whereas procedure justice has no effect on encounter satisfaction directly, there was indirect effect through customers' positive emotion. (3) As a result of the analysis for the effect of perception of recovery justice on recovery satisfaction, the effect of interactional justice was significant only. Distributional and procedural justice have indirect effect on recovery satisfaction through positive emotion or encounter satisfaction. (4) Customers' positive emotion positively affected encounter satisfaction and recovery satisfaction. (5) Relationship quality negatively moderated the relationship between procedural justice and positive emotion while customer participation positively moderated two paths that distributional justice to encounter satisfaction and interactional justice to recovery satisfaction.

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ON THE ADMISSIBILITY OF HIERARCHICAL BAYES ESTIMATORS

  • Kim Byung-Hwee;Chang In-Hong
    • Journal of the Korean Statistical Society
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    • v.35 no.3
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    • pp.317-329
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    • 2006
  • In the problem of estimating the error variance in the balanced fixed- effects one-way analysis of variance (ANOVA) model, Ghosh (1994) proposed hierarchical Bayes estimators and raised a conjecture for which all of his hierarchical Bayes estimators are admissible. In this paper we prove this conjecture is true by representing one-way ANOVA model to the distributional form of a multiparameter exponential family.

Vegetation Structure and Distributional Characteristics of Abies koreana Forests in Mt. Halla (한라산 구상나무림의 식생구조와 분포 특성)

  • Song, Kuk-Man;Kim, Chan-Soo;Koh, Jung-Goon;Kang, Chang-Hun;Kim, Moon-Hong
    • Journal of Environmental Science International
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    • v.19 no.4
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    • pp.415-425
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    • 2010
  • The purpose of the present study was to analyze the vegetation structure and distributional characteristics of Abies koreana forests in Mt. Halla, and to provide basicdata for an ecological study on Abies koreana in Mt. Halla. The results of the analysis showed that the mean importance percentage(M.I.P,) of Abies koreana in the Youngsil and Bangaeoreum and the Azalea field were 28.3%, 23.6%, and 46.4%, respectively. The ratios of DBH (diameter at breast height) to height were similar in all region, except in the Azalea field, where Abies koreana of various ages, both young and old, were found. The species diversity (H) of the upper and lower layers in the Youngsil and Bangaeoreum and in the Azalea field were 0.625 and 0.810, 0.731 and 0.848, and 0.342 and 0.757, respectively. A total of 52 community were distributed at locations higher than 1,300m above sea level. The proportions of each community in the whole Abies koreana forest were 56.5%(Azalea field), 11.0% (Youngsil trail at 1,550-1,650 m above sea level), and 8.1%(Janggumok and Kundurewat region). The total area of the Abies koreana forest was calculated to be 795.3ha by combining all the areas of each community. An Abies koreana forest with the largest area was found at locations 1,500-1,600 m above sea level, taking up 38.8% of the total Abies koreana forest area. For the slopes of the distributional area of Abies koreana, 46.1%(highest proportion) of the total area was $10\sim25^{\circ}$, and for the azimuth of the distributional area, 17.4%(the highest proportion) of the total area was $0-45^{\circ}$. The vegetation structure showed large differences between areas. It was found, however, that the distribution was mostly in the areas with a relatively gentle slope. It is suggested that research be done to forecast the possible changes in the differences in the vegetation structures between different areas caused by climate changes. In addition, there is a need to monitor the Abies koreana and alpine plants in the subalpine zones of Mt. Halla, which are sensitive to climate change, to obtain the basic data that are necessary for the protection and maintenance of the ecosystem.

Issues of Workplace in Korea: How to Inspire Temporary Workers?

  • Yang, Hoe-Chang;Khan, Tasnuva
    • Asian Journal of Business Environment
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    • v.3 no.1
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    • pp.23-27
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    • 2013
  • Purpose - This study will focus on motivation of temporary workers working in distributors as well as generic companies, especially MPS (motivating potential score) proposed by job characteristics model. We think that temporary workers required intrinsic motivation in order to commit with their organization because they are difficult switch-regular workers due to glass ceiling. Research design, data, methodology - This study operates a survey targeting temporary workers, specifically, we used 144 copies except uncollected copies and dishonesty response of total 165 copies on analysis. We used multiple regression and 3 step regression to investigate the proposed model. Results - The high level of perceived distributional justice and procedural justice was increased the level of organizational commitment, respectively. And, MPS was increased the level of organizational commitment, too. Finally, this study showed that both justice and Job characteristics were very important to increase organizational commitment. Conclusions - In order to inspire temporary workers, the company provides placing enough considering job characteristics as well as fairness of the procedure and distribution. Also, to more fully understand the underlying processes between HRM (Human Resource Management) concepts, new fundamental methods may be required such as switch full-time opportunities.

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Bearing fault detection through multiscale wavelet scalogram-based SPC

  • Jung, Uk;Koh, Bong-Hwan
    • Smart Structures and Systems
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    • v.14 no.3
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    • pp.377-395
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    • 2014
  • Vibration-based fault detection and condition monitoring of rotating machinery, using statistical process control (SPC) combined with statistical pattern recognition methodology, has been widely investigated by many researchers. In particular, the discrete wavelet transform (DWT) is considered as a powerful tool for feature extraction in detecting fault on rotating machinery. Although DWT significantly reduces the dimensionality of the data, the number of retained wavelet features can still be significantly large. Then, the use of standard multivariate SPC techniques is not advised, because the sample covariance matrix is likely to be singular, so that the common multivariate statistics cannot be calculated. Even though many feature-based SPC methods have been introduced to tackle this deficiency, most methods require a parametric distributional assumption that restricts their feasibility to specific problems of process control, and thus limit their application. This study proposes a nonparametric multivariate control chart method, based on multiscale wavelet scalogram (MWS) features, that overcomes the limitation posed by the parametric assumption in existing SPC methods. The presented approach takes advantage of multi-resolution analysis using DWT, and obtains MWS features with significantly low dimensionality. We calculate Hotelling's $T^2$-type monitoring statistic using MWS, which has enough damage-discrimination ability. A bootstrap approach is used to determine the upper control limit of the monitoring statistic, without any distributional assumption. Numerical simulations demonstrate the performance of the proposed control charting method, under various damage-level scenarios for a bearing system.

Characterizing Social Welfare Index between Urban and Rural Regions in China: An Application of Principal Component Analysis (중국의 도농 간 사회후생지표 특성에 관한 연구: 주성분분석에 의한 접근)

  • Rhee, Hyun-Jae
    • The Journal of the Korea Contents Association
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    • v.17 no.7
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    • pp.371-383
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    • 2017
  • The aim of this paper is to investigate adjusting process of trade-off relationship between economic growth and income distribution in China which is established by mixed with social and market-oriented economic systems. The characteristic nature of social welfare index in urban and rural regions in China is examined by employing principal component analysis. Empirical evidences reveal that unlike national wide or urban region, the increases of income contribute to improve social well-being in rural region, but not social welfare index. Accordingly, it can be said that although social well-being in rural region seems to be harmful because of weakly organized social welfare index, the potentiality exists to improve social well-being by increased income. Taken all together, the results signifies that the mixed economic system such as China might distribute its increased income appropriately, however, the distributional system is hardly operated to improve social welfare index. And thus the distributional system has to be amended to enhance social well-being in China.

Effect of Job Autonomy of Local Government Officials on Organizational Citizenship Behavior: Mediating Effect of Organizational Justice Perception and Moderating Effect of Self-Efficacy (지방공무원의 직무자율성이 조직시민행동에 미치는 영향: 조직공정성의 매개효과와 자기효능감의 조절효과 분석)

  • Jin, Yoon-Hee
    • The Journal of the Korea Contents Association
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    • v.21 no.10
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    • pp.494-507
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    • 2021
  • This study conducted a regression analysis on 312 local government officials in Gyeonggi-do to verify the hypothesis on the relationship between job autonomy and organizational citizenship behavior. Path analysis was conducted to analyze the mediating effect of organizational fairness recognition and the moderating effect of self-efficacy. Looking at the analysis results, first, it was confirmed that the higher the degree of job autonomy perceived by the members of the organization, the more positive (+) organizational citizenship behavior was. Second, the partial mediating effect of procedural justice was confirmed in the relationship between autonomy and organizational citizenship behavior. On the other hand, the mediating effect of distributional justice was rejected in the relationship between autonomy and organizational citizenship behavior. Third, self-efficacy controlled the mediating role between job autonomy and organizational citizenship behavior in recognition of procedural justice. Fourth, it was analyzed that self-efficacy plays a controlling role between job autonomy and organizational citizenship behavior. The results of this study are expected to contribute to the development of organizational behavior theory through preceding factors of organizational citizenship behavior to improve the organizational performance of local public officials.