• Title/Summary/Keyword: Level sets

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Experimental Study for Influence of Summertime Heat Sources and Basic States on Rossby Wave Propagation (여름철 열원과 기본장이 로스비 파동전파에 미치는 영향에 대한 실험 연구)

  • Kim, Seong-Yeol;Ha, Kyung-Ja;Yun, Kyung-Sook
    • Atmosphere
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    • v.20 no.4
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    • pp.505-518
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    • 2010
  • We investigated the impacts of the diabatic heating location, vertical profile and basic state on the Rossby wave propagation. To examine the dynamical process of individual responses on the regional heat source, a dry version of the linear baroclinic model was used with climatological summertime (JJA) mean basic state and vertical structure of the diabatic heating for 1979-2008. Two sets of diabatic heating were constructed of those positioned in the mid-latitudes (Tibetan Plateau, eastern Mediterranean Sea, and the west-central Asia) and the tropics (the southern India, Bay of Bengal, and western Pacific). It was found that using the principal component analysis, atmospheric response to diabatic heating reaches to the steady state in 19th days in time. The prescribed mid-latitude forcing forms equivalent barotropic Rossby wave propagation along the westerly Asia jets, whereas the tropical forcing generates the Rossby wave train extending from the tropics to mid-latitudes. In relation to the maximum vertical profile, the mid-level forcing reveals a stronger response than the lower-level forcing, which may be caused by more effective Rossby wave response by the upper-level divergent flow. Under the different sub-seasonal mean state, both of the tropical and mid-latitude forcing induce the different sub-seasonal response intensity, due to the different basic-state wind.

Classification of Imbalanced Data Using Multilayer Perceptrons (다층퍼셉트론에 의한 불균현 데이터의 학습 방법)

  • Oh, Sang-Hoon
    • The Journal of the Korea Contents Association
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    • v.9 no.7
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    • pp.141-148
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    • 2009
  • Recently there have been many research efforts focused on imbalanced data classification problems, since they are pervasive but hard to be solved. Approaches to the imbalanced data problems can be categorized into data level approach using re-sampling, algorithmic level one using cost functions, and ensembles of basic classifiers for performance improvement. As an algorithmic level approach, this paper proposes to use multilayer perceptrons with higher-order error functions. The error functions intensify the training of minority class patterns and weaken the training of majority class patterns. Mammography and thyroid data-sets are used to verify the superiority of the proposed method over the other methods such as mean-squared error, two-phase, and threshold moving methods.

A Comparison between Home Care Nursing Interventions for Hospice and General Patients (가정 호스피스 대상자와 일반 가정간호 대상자에게 제공된 간호중재 비교)

  • 용진선;노유자;한성숙;김명자
    • Journal of Korean Academy of Nursing
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    • v.31 no.5
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    • pp.897-911
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    • 2001
  • The purpose of the study was to compare home care nursing intervention activities analyzed by the Nursing Intervention Classification (NIC) system for hospice and general patients. Method: For the descriptive survey study, data was collected by reviewing charts of 151 hospice patients and 421 general patients who registered in the department of home health care nursing at K Hospital. Results: According to the NIC system application, there were 2380 total nursing interventions used for the hospice patients and 8725 for the general home care patients. For both sets of patients (hospice vs. general), the most frequently used nursing intervention in level 1 was the Physiological: Complex domain (40.13 vs. 31.06 percent), followed by the Safety domain; in level 2, the Risk Management class (28.4 vs. 27.70 percent), followed by Tissue Perfusion Management; and in level 3, Vital Sign Monitoring (6.18 vs. 4.84 percent), followed by Health Screening. Conclusion: The study showed that there was a lack of specialized hospice nursing interventions such as emotional, family and spiritual support, and care for dying hospice patients.

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Evaluation of Robust Classifier Algorithm for Tissue Classification under Various Noise Levels

  • Youn, Su Hyun;Shin, Ki Young;Choi, Ahnryul;Mun, Joung Hwan
    • ETRI Journal
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    • v.39 no.1
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    • pp.87-96
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    • 2017
  • Ultrasonic surgical devices are routinely used for surgical procedures. The incision and coagulation of tissue generate a temperature of $40^{\circ}C-150^{\circ}C$ and depend on the controllable output power level of the surgical device. Recently, research on the classification of grasped tissues to automatically control the power level was published. However, this research did not consider the specific characteristics of the surgical device, tissue denaturalization, and so on. Therefore, this research proposes a robust algorithm that simulates noise to resemble real situations and classifies tissue using conventional classifier algorithms. In this research, the bioimpedance spectrum for six tissues (liver, large intestine, kidney, lung, muscle, and fat) is measured, and five classifier algorithms are used. A signal-to-noise ratio of additive white Gaussian noise diversifies the testing sets, and as a result, each classifier's performance exhibits a difference. The k-nearest neighbors algorithm shows the highest classification rate of 92.09% (p < 0.01) and a standard deviation of 1.92%, which confirms high reproducibility.

Dynamic Capabilities, Environmental Dynamism and Small and Medium Enterprises' Internationalization Level

  • ALI, Hazem;HAO, Yunhong;AIJUAN, Chen
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.9
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    • pp.527-536
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    • 2020
  • International business research presents a broad consensus on the importance of dynamic capabilities in the internationalization of SMEs. However, there is a lack of research on assessing the impact of dynamic capabilities and the level of SMEs' internationalization operating in a turbulent and dynamic business environment. This study examines the impact of environmental dynamism and three sets of dynamic capabilities, namely, sensing, seizing, and reconfiguring capabilities on internationalized SMEs' geographic scope. In addition, this research examines the association between internationalized SMEs' characteristics: SME's age, size, and SME owner/manager's international experience and SMEs' geographic scope. This study used a quantitative research and employed survey questionnaires to collect data from 305 internationalized Malaysian manufacturing SMEs. Anova tests and Chi Square tests were employed to analyze data collected from respondents using SPSS. Research findings revealed that environmental dynamism and dynamic capabilities have a significant impact on internationalized SMEs' geographic scope, however, none of the internationalized SMEs' characteristics had a significant relationship with their geographic scope. The result of this research suggest internationalized SMEs owner/managers need to possess sensing, seizing and reconfiguring capabilities, and monitor business environmental dynamism to increase their geographic scope. This paper ends with drawing a set of concluding remarks and recommendations.

Consumer shopping orientation and perceived value according to the level of use of mobile fashion shopping (모바일 패션 쇼핑 이용정도에 따른 소비자의 쇼핑성향과 지각된 가치)

  • Chae, Jin Mie
    • The Research Journal of the Costume Culture
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    • v.24 no.1
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    • pp.79-92
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    • 2016
  • The purpose of this study is to investigate the differences in fashion shopping orientation and perceived value according to the level of use of mobile fashion shopping. Furthermore, the effect of fashion shopping orientation on perceived value was analyzed. To estimate the level of use of mobile fashion shopping, respondents were classified into four different groups in terms of their frequency of buying fashion products and the period for which they had bought fashion products. The survey was limited to adults aged 20-40 years who had purchased fashion products in a mobile shopping mall. The questionnaire was carried out from April 15, 2015 to April 22, 2015 and 430 sets of useful response data were analyzed using SPSS 17.0. The results of this study were as follows: First, fashion shopping orientation for mobile shopping consumers was divided into four factors as follows: convenience/economic shopping, ostentation/trend shopping, enjoyment shopping, and impulse shopping. Second, there was a significant difference in all the fashion shopping orientation factors except for convenience/economic shopping according to each classified group: short/few, long/few, short/many, and long/many. In addition, there was a significant difference in perceived value according to each group. Third, all the fashion shopping orientation factors except for impulse shopping had a significant influence on perceived value. Fourth, fashion shopping orientation factors had a slightly significant influence on the perceived value according to each group.

Optimization of Several Environmental Factors to Human Performance by Using Taguchi Method

  • Ismail, A.R.;Haniff, M.H.M.;Yusof, M.Y.M.;Rahman, M.N.A.;Ghani, J.A.
    • Industrial Engineering and Management Systems
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    • v.9 no.2
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    • pp.157-164
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    • 2010
  • The objective of this study is to determine the dominance effects of environmental factors such as Illuminance, humidity and Wet Bulb Globe Temperature (WBGT) on the operators' productivity at Malaysian electronic industry. A case study was carried out at an electronic components assembly factory. The environmental factors examined were the Illuminance (lux), humidity and WBGT of the surrounding workstation area. Two sets of representative data including the illuminance, humidity and WBGT level and production rate were collected during the study. The production rate data were collected through observations and survey questionnaires while the illuminance level was measured using photometer model RS 180-7133, the humidity and WBGT level were measured by using Quest Temp apparatus and humidity. Taguchi Method was utilized to find the sequence of dominant factors that contributed to the productivity of operator at that specified production workstation. The study reveals that the dominant factor contributed to the productivity was WBGT, followed by illuminance and humidity.

Indexing Considering Video Rating of Scenes in Video (동영상의 장면별 비디오 등급을 고려한 색인)

  • Kim Young-Bong
    • Journal of Game and Entertainment
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    • v.2 no.2
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    • pp.51-60
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    • 2006
  • Recently, many streaming videos including drama, music videos, and movies have been extensively given on the web. Such video services are on negative lines in any service restriction depending on the age of users and then whole part of a video have been restricted considering the age of users. Therefore, in this paper, we will present a new method that provides the access depending on the ages of users and also sets the video rating of each scene in a video. To get this restricted access for video, we will first divide a streaming video into many scenes using histogram techniques. Each scene gets an access control depending on the nudity level. Finally, we will make the video indexing including the access level depending on its nudity level and then hide restricted scenes using several masks in playing that streaming video.

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Internal Event Level 1 Probabilistic Safety Assessment for Korea Research Reactor (국내 연구용원자로 전출력 내부사건 1단계 확률론적안전성평가)

  • Lee, Yoon-Hwan;Jang, Seung-Cheol
    • Journal of the Korean Society of Safety
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    • v.36 no.3
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    • pp.66-73
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    • 2021
  • This report documents the results of an at-power internal events Level 1 Probabilistic Safety Assessment (PSA) for a Korea research reactor (KRR). The aim of the study is to determine the accident sequences, construct an internal level 1 PSA model, and estimate the core damage frequency (CDF). The accident quantification is performed using the AIMS-PSA software version 1.2c along with a fault tree reliability evaluation expert (FTREX) quantification engine. The KRR PSA model is quantified using a cut-off value of 1.0E-15/yr to eliminate the non-effective minimal cut sets (MCSs). The final result indicates a point estimate of 4.55E-06/yr for the overall CDF attributable to internal initiating events in the core damage state for the KRR. Loss of Electric Power (LOEP) is the predominant contributor to the total CDF via a single initiating event (3.68E-6/yr), providing 80.9% of the CDF. The second largest contributor is the beam tube loss of coolant accident (LOCA), which accounts for 9.9% (4.49E-07/yr) of the CDF.

Joint Characteristics in Sedimentary Rocks of Gyeongsang Supergroup (경상누층군 퇴적암의 절리 특성 연구)

  • Chang, Tae-Woo;Son, Byeong-Kook
    • The Journal of Engineering Geology
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    • v.19 no.3
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    • pp.351-363
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    • 2009
  • Two orthogonal joint sets develop well only in sandstone beds in the sandstone-mudstone sequences of Gumi and Dasa outcrops within Cretaceous Gyeongsang Basin. And various joint data are similar in the beds of the same thickness in both outcrops, meaning that the joint sets were homogeneously produced by extensional deformation in the same regional stress field. Most of joints in the sandstone beds are orthogonal to, and confined by bed boundaries, which are believed to be formed by hydrofracturing during consolidation after burial. Two orthogonal joint sets are considered to be almost coeval on the basis of mutual abutting relationship which makes up fracture grid-lock and a product of rapid switching of ${\sigma}_2$ and ${\sigma}_3$ axes with constant ${\sigma}_1$ direction oriented to vertical. The joint sets in the sandstone beds show planar surfaces, parallel orientations and regular spacing, with joint spacing linearly proportional to bed thickness. The spacing distributions of the joints seem to correspond to log-normal to almost normal distribution in most of the beds. But multilayer joints do not display regular spacing and dominant size. Either joint set in this study is characterized by a high level of joint density and a saturated spacing distribution as indicated by the mode/mean ratio values and the Cv(coefficient of variance) values. Joint aperture tends to increase with the vertical length of the joints controlled by bed thickness.