• Title/Summary/Keyword: Re-sampling

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Recent progress in studies of the Cladocera (Crustacea: Branchiopoda) of South Korea with seven new records for the Korean Peninsula

  • Kotov, Alexey A.;Sinev, Artem Y.;Garibian, Petr G.;Neretina, Anna N.;Jeong, Hyun Gi;Lee, Wonchoel;Chae, Kyu-Seok;Min, Gi-Sik
    • Journal of Species Research
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    • v.6 no.spc
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    • pp.227-246
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    • 2017
  • A study of the Cladocera (Crustacea: Branchiopoda) from the Korean Peninsula resulted in the checklist of Jeong et al. (2014). Several sampling campaigns conducted by our team since 2014, with the framework of the programs supported by the National Institute of Biological Resources (NIBR), have resulted in a considerable increase in the number of water bodies studied in South Korea. In this report, seven new records for the Korean Peninsula are provided: (1) Macrothrix vietnamensis Silva-Briano, Dieu and Dumont, 1999; (2) Disparalona chappuisi (Brehm, 1931); (3) Pleuroxus(Picripleuroxus) quasidenticulatus (Smirnov, 1996); (4) Acroperus africanus Neretina and Kotov, 2015; (5) Alona ossiani herricki Sinev, 2013; (6) Coronatella trachystriata (Chen, Zhang and Liu, 1994); (7) Leydigia louisi Jenkin, 1934. Most of these taxa belong to the southern thermophilic complex. In addition several populations of Pleuroxus (Picripleuroxus) denticulatus Birge, 1879 and Pseudochydorus globosus (Baird, 1843) were re-studied, and their presence in Korea is confirmed. Through increased collection efforts and the application of molecular methods we are confident that more new records of Korean fauna will be published in the near future.

Review of Exposure Assessment to Obtain Exposure Factors of Consumer Products (소비 생활용품의 노출계수 조사 방법의 고찰)

  • Park, Ji Young;Lee, Kiyoung;Shin, Ho-Sang;Yang, Wonho
    • Journal of Environmental Health Sciences
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    • v.39 no.6
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    • pp.532-540
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    • 2013
  • Background: Exposure factors for consumer products have been developed since the 1980s. Such exposure factors are important in risk assessment. Since the exposure/use patterns of consumer products in a country may reflect its respective cultural, meteorological, and socio-economic circumstances, unique Korean exposure factors for consumer products are needed. Such exposure factors are required for newly-enacted chemical regulations in Korea. For this review, published papers and survey reports on exposure factors of consumer products were examined for their assessment methodologies. Results: Investigation into exposure factors for consumer products used a variety of methods: home visit, online, telephone, and mail surveys using questionnaires; face to face interviews; modeling using a constructed database; and direct measurement. To collect more accurate exposure information or to check the reliability of the sampling method, some studies were repeated using the same questionnaire, in-home observation, direct measurement of usage, and videotaping. In Korea, nationwide exposure surveys were conducted five times over five years to obtain Korean exposure factors. However, with the exception of the $5^{th}$-year study, the surveys were online questionnaires and only the $5^{th}$-year study validated the accuracy of exposure information by re-visits and direct measurement. Conclusion: Accurate exposure factors are an essential part of risk assessment to assure safe use of consumer products. For better and safer management of consumer products, accurate exposure factors in Korea should be assessed for various exposure pathways.

Characteristics of the Electric and Magnetic Field Waveforms Radiated by Lightning Discharges (뇌방전에 의해 방사되는 전계와 자계파형의 특성)

  • 이복희;이경옥
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.7 no.4
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    • pp.300-309
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    • 1996
  • The electric and magnetic fields radiated by lightning discharges are significantly changeable in amplitude and time, one of the topics concerning electromagnetic compatibility of modern electronic systems is the efficient and economic protection against transient voltages caused by not only by direct but also by nearly lightning strokes. In this paper, in order to obtain the detailed informations about lightning electromagnetic impulse waveforms, the electric and magnetic fields radiated by lightning discharges in the summer of 1995 were measured by a fast electric antenna and a loop-type magnetic field sensor, and their charac- teristics were presented and analyzed. The signals of the electric and magnetic fields were re- corded continuously by a transient digitizer having a resolution of 12 bit and a memory capacity of 5000 point and using a sampling time of 200 ns. The electric and magnetic field waveforms associated with lightning return strokes are significantly different with those of intracloud discharges. The magnetic fields radiated by intracloud lightning discharges have essentially the same waveforms as the electric field when the lightning discharhes are at distance of 50 km or more. Also the main frequency components of the electric and magnetic fields radiated by lightning discharges range from a few kHz to several hundred kHz.

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The Effect of Environmental Class with Animistic Viewpoint on Elementary Students' Environmental Awareness (물활론적 관점의 환경수업이 초등학생들의 환경인식에 미치는 영향)

  • Kim, Soon-Shik
    • Journal of Environmental Science International
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    • v.20 no.12
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    • pp.1625-1634
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    • 2011
  • The aim of this study is to clarify what influence has on elementary school children's environmental awareness in time of teaching environmental problems from an animistic viewpoint and from non-animistic viewpoint. For this purpose, this study carried out its research targeting 126 students in fourth grade at M elementary school located in U Metropolitan City. This study suggested the environmental problems by re-edifying the already suggested environmental problems from an animistic viewpoint to 62 students for two classes which were classified as an experimental group after sampling 10 cases of the representative environmental problems that might derive from the earth system, and conducted the class on 10 main topics relevant to the problematic situation of environment with an animistic viewpoint excluded targeting the remaining 64 students forming a comparison group. The results of this study were as follows: First, there appeared an ex-ante ex-post statistically significant difference in the awareness of environmental problems from the experimental group which received an environmental class from an animistic viewpoint. However, there didn't appear a statistically significant difference from the comparison group. This study interprets this result to mean that elementary students' awareness of environmental problems increase because they think about the environmental problems by associating them with a problem of life when the students receive the environmental class from an animistic viewpoint. Second, there appeared an ex-ante ex-post statistically significant difference in the awareness of environmental problems from the experimental group which received an environmental class from an animistic viewpoint. However, there didn't appear a statistically significant difference from the comparison group. Regarding this aspect, this study believes that the experimental group shows much higher willingness to environmental act in comparison with the comparison group because elementary school students think of inanimate objects as living things.

Determination of Optimal Cluster Size Using Bootstrap and Genetic Algorithm (붓스트랩 기법과 유전자 알고리즘을 이용한 최적 군집 수 결정)

  • Park, Min-Jae;Jun, Sung-Hae;Oh, Kyung-Whan
    • Journal of the Korean Institute of Intelligent Systems
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    • v.13 no.1
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    • pp.12-17
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    • 2003
  • Optimal determination of cluster size has an effect on the result of clustering. In K-means algorithm, the difference of clustering performance is large by initial K. But the initial cluster size is determined by prior knowledge or subjectivity in most clustering process. This subjective determination may not be optimal. In this Paper, the genetic algorithm based optimal determination approach of cluster size is proposed for automatic determination of cluster size and performance upgrading of its result. The initial population based on attribution is generated for searching optimal cluster size. The fitness value is defined the inverse of dissimilarity summation. So this is converged to upgraded total performance. The mutation operation is used for local minima problem. Finally, the re-sampling of bootstrapping is used for computational time cost.

The Study on the Comparative Analysis of the Aquaculture Production Efficiency Regarding Methods and Species (양식업의 양식방법별 어종별 생산효율성 비교분석에 관한 연구)

  • Park, Cheol-Hyung
    • The Journal of Fisheries Business Administration
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    • v.43 no.2
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    • pp.79-94
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    • 2012
  • The purpose of this study is to investigate the production efficiencies of the Korean aquaculture fishery with respect to species and methods using a Data Envelopment Analysis. The study extracted the 8 fishes in each of the sea cage culture, aquarium basin, and enclosed aquaculture for the analytical purposes. First, the study estimated the technical, pure technical, and scale efficiencies of the total of 24 aquaculture fishes based on the traditional DEA under the assumptions of both CRS and VRS. 2 fishes were identified as the efficient DMUs under the CCR-model, and 6 fishes under the BCC-model. Second, we tested to see if there was any difference in production efficiencies regarding those three different methods of aquaculture. we could not find any evidence of the differences in efficiency using a rank sum test based on the traditional DEA. However, we could do find that the pure technical efficiency in the sea cage culture was lower than others at 1% level of significance and the pure technical efficiency in enclosed aquaculture was also lower than others at 5% level of significance using Bilateral-DEA, which could explicitly consider the heterogeneity in the 3 production methods of aquaculture. Finally, the study obtained the 95% confidence intervals of the efficiency scores for the 24 fishes under our study using the smoothed bootstraping method in the process of the re-sampling in cooperation with both a kernel density estimation and a reflection method. At the same time, we could estimate the bias-corrected efficiency scores while the traditionally estimated efficiency scores suffered from the biases in the process of solving a linear programming with the deterministic nature of a production frontier. And hence, we could distinguish the differences in production efficiencies of the 8 fishes with respect to those 3 methods of aquaculture.

Study on the Relation between Servicescape recognized by Sports Center, Customer Satisfaction, Customer Trust, and Customer's Intention to Reenroll (스포츠센터 이용고객이 인식하는 서비스스케이프가 고객만족, 고객신뢰 및 재등록의도와의 관계)

  • Kim, Soon-Hee
    • The Journal of the Korea Contents Association
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    • v.14 no.10
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    • pp.287-297
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    • 2014
  • The purpose of this study was to find out the relation between servicescape recognized by sports center and customer satisfaction, customer trust and customer's intention to reenroll. For the subject of this study, we selected 363 persons among customers who used 5 sports centers located at 'B' Metropolitan city & 'K' do (prefecture) through the Convenient Sampling Method. For the analysis, we used SPSS 18.0 Statistics Package as a research tool and have carried out Factor Analysis, Reliability Analysis, Co-relation Analysis, Frequency Analysis, and Regression Analysis. The results were as follows: First, the servicescape has a positive effect on the customer satisfaction. Second, the customer satisfaction has a positive effect on the customer trust. Third, the customer satisfaction has a positive effect on the customer's intention to re-enroll. Fourth, the customer trust has a positive effect on the customer's intention to reenroll.

Correlation between Customer Orientation and Job Stress due to Degree of Emotional Labor on Security Agents (시큐리티 요원의 감정노동 수준에 따른 직무스트레스와 고객지향성의 관계)

  • Kim, Eui-Young;Lee, Jong-Hwan;Cho, Sung-Jin
    • Convergence Security Journal
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    • v.14 no.3_2
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    • pp.23-35
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    • 2014
  • This study aims to verify the relationship between customer orientation and job stress due to the degree of emotional labor on security agents. Objects of study are from 10 security companies, randomly selected from those registered on the Regional Police Agencies in Daejeon and Chungnam, from November 10th to 20th, 2013; thirty agents from each company, or three-hundred in total, were selected as research subjects by random sampling method. Twenty-five subjects were excluded for poor response contents and/or low reliability. Thus, only 275 subjects were included in actual analysis. The research tool was the questionnaire which was re-composed on the basis of domestic/overseas preliminary studies, while the data was processed through the frequency analysis, the reliability analysis, the confirmatory factor analysis and structure model analysis, using SPSS version 19.0 and AMOS 17.0 statistics package. Through the data analysis following the research methods above, the conclusion was acquired as follows. First, as job stress of security agents decreased, customer orientation increased. Second, the group of security agents with lower level of emotional labor positively affected job stress and customer orientation.

Analysis of Geometric Calibration Accuracy using the Results from IR Channel Nominal Radiometric Calibration (적외채널 기본 복사보정 결과를 이용한 기하보정 처리의 정확도 분석)

  • Seo, Seok-Bae;Kwon, Eun-Joo;Jin, Kyoung-Wook
    • Aerospace Engineering and Technology
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    • v.12 no.2
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    • pp.147-155
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    • 2013
  • The nominal radiometric calibration equation and additional five algorithms are applied in the infrared channel radiometric calibration for the COMS (Communication, Ocean, Meteorological Satellite) MI (Meteorological Imager). The processing end time of the radiometric calibration is directly related with the start time of geometric calibration processing since the geometric calibration processing is followed by that of the radiometric calibration. This paper describes comparison and analysis results for geometric calibration processing using two types of the radiometric calibration results, outputs from only the nominal radiometric calibration equation and outputs from the complete one (the nominal radiometric calibration equation with additional five algorithms), to propose a method with the earlier start time of the geometric calibration processing. Experimental results show that both of radiometric calibration results, from the nominal radiometric calibration equation with a fast processing speed and from the complete one with accurate radiometric values, can be used in the geometric calibration as the appropriate inputs because those processing results satisfied the requirements of geometric calibration processing accuracy. Thus the radiometric calibration results from the nominal radiometric calibration equation can be used to improve geometric calibration processing time.

Analysis on Digital Image Composite Using Interpolation (보간을 이용한 디지털 이미지 합성 분석)

  • Song, Geun-Sil;Yun, Yong-In;Lee, Won-Hyung
    • Journal of Korea Multimedia Society
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    • v.13 no.3
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    • pp.457-466
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    • 2010
  • In this paper, we propose a new method for detecting digital forgery that identify interpolated region between digital composited images. For detecting the interpolation factor and the tampered regions, we perform two algorithms: The first algorithm is to estimate the interpolation factors using the differential equation for forgery image along the horizontal, vertical, and diagonal directions, respectively; The second algorithm is to scan the interpolation factors along each direction for detection areas as the mask of the optical window size($64{\times}64$) in order to find out the forgery region. A detection map of the forgery is classified with the magnitude of estimated interpolation factors into colors. This detection map can be used to find out interpolated regions from the tampered image. Experimental results demonstrate the proposed algorithms are proven on several examples. We also show the proposed approach is to accurately detect interpolated regions from digital composite images.