• Title/Summary/Keyword: performance based

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A Study on the Method of Producing the 1 km Resolution Seasonal Prediction of Temperature Over South Korea for Boreal Winter Using Genetic Algorithm and Global Elevation Data Based on Remote Sensing (위성고도자료와 유전자 알고리즘을 이용한 남한의 겨울철 기온의 1 km 격자형 계절예측자료 생산 기법 연구)

  • Lee, Joonlee;Ahn, Joong-Bae;Jung, Myung-Pyo;Shim, Kyo-Moon
    • Korean Journal of Remote Sensing
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    • v.33 no.5_2
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    • pp.661-676
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    • 2017
  • This study suggests a new method not only to produce the 1 km-resolution seasonal prediction but also to improve the seasonal prediction skill of temperature over South Korea. This method consists of four stages of experiments. The first stage, EXP1, is a low-resolution seasonal prediction of temperature obtained from Pusan National University Coupled General Circulation Model, and EXP2 is to produce 1 km-resolution seasonal prediction of temperature over South Korea by applying statistical downscaling to the results of EXP1. EXP3 is a seasonal prediction which considers the effect of temperature changes according to the altitude on the result of EXP2. Here, we use altitude information from ASTER GDEM, satellite observation. EXP4 is a bias corrected seasonal prediction using genetic algorithm in EXP3. EXP1 and EXP2 show poorer prediction skill than other experiments because the topographical characteristic of South Korea is not considered at all. Especially, the prediction skills of two experiments are lower at the high altitude observation site. On the other hand, EXP3 and EXP4 applying the high resolution elevation data based on remote sensing have higher prediction skill than other experiments by effectively reflecting the topographical characteristics such as temperature decrease as altitude increases. In addition, EXP4 reduced the systematic bias of seasonal prediction using genetic algorithm shows the superior performance for temporal variability such as temporal correlation, normalized standard deviation, hit rate and false alarm rate. It means that the method proposed in this study can produces high-resolution and high-quality seasonal prediction effectively.

A Study on the Attributes determining the Extent of Autonomy in Decision Making for Korean Subsidiaries of Multinational Corporations - Focused on Semiconductor Industry Related Companies - (다국적기업 한국자회사의 의사결정 자율성에 영향을 미치는 요인에 관한 연구 -반도체산업 관련기업체를 중심으로-)

  • Chung, Nak-Kyung;Kim, Hong
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.3 no.4
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    • pp.1-41
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    • 2008
  • The Korean semiconductor industry has made a great contribution to growth of Korean economy for the last decades by maintaining a top position in terms of Korean total annual export volume. However, the advanced semiconductor equipment and materials that are used for the production of semiconductor devices still depend on the suppliers from Europe, Japan, and America who have an influential position in the Korean semiconductor industry. The objective of this study is to empirically investigate the attributes determining the extent of autonomy in decision making for the Korean subsidiaries of multinational corporations in the semiconductor industry. This study found there were differences in the extent of autonomy in decision making in terms of the global strategies the multinational corporations pursue. This study surveyed employees at the Korean subsidiaries and joint venture companies of semiconductor multinational corporations and collected 726 survey questionnaires. Several statistical analyses including frequency analysis, reliability analysis, factor analysis, multiple regression analysis and ANOVA were performed using the collected sample data. Based on the analyses, this study found as follows: Firstly, from the factor analysis, this study found Korean subsidiaries faced three sources of uncertainties stemmed from political conditions, competent conditions, demand and supply conditions. The internal resources were characterized by the independencies of production capability, financial capability, marketing capability and human resource management capability. The operational performance was determined by total revenue, net profit and market share growth. Secondly, it was found the uncertainties from political condition and competent condition and the independencies of financial capability and marketing capability partially influenced the extent of autonomy in decision making. The independencies of production capability and human resource management capability significantly influenced the autonomy of decision making in the most areas. It was also found an increase of total revenue, net profit and market share growth partially affected the extent of autonomy in decision making of the Korean subsidiaries. Finally, it was found that the polycentrism of global management by multinational corporations seemed to bring a higher extent of autonomy in decision making than ethnocentrism or geocentrism of global management. Based on the results, this study provided managerial implications regarding the extent of autonomy in decision making for Korean subsidiaries of multinational corporations in order to help management to enhance their business capabilities.

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Development of a Real-Time Mobile GIS using the HBR-Tree (HBR-Tree를 이용한 실시간 모바일 GIS의 개발)

  • Lee, Ki-Yamg;Yun, Jae-Kwan;Han, Ki-Joon
    • Journal of Korea Spatial Information System Society
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    • v.6 no.1 s.11
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    • pp.73-85
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    • 2004
  • Recently, as the growth of the wireless Internet, PDA and HPC, the focus of research and development related with GIS(Geographic Information System) has been changed to the Real-Time Mobile GIS to service LBS. To offer LBS efficiently, there must be the Real-Time GIS platform that can deal with dynamic status of moving objects and a location index which can deal with the characteristics of location data. Location data can use the same data type(e.g., point) of GIS, but the management of location data is very different. Therefore, in this paper, we studied the Real-Time Mobile GIS using the HBR-tree to manage mass of location data efficiently. The Real-Time Mobile GIS which is developed in this paper consists of the HBR-tree and the Real-Time GIS Platform HBR-tree. we proposed in this paper, is a combined index type of the R-tree and the spatial hash Although location data are updated frequently, update operations are done within the same hash table in the HBR-tree, so it costs less than other tree-based indexes Since the HBR-tree uses the same search mechanism of the R-tree, it is possible to search location data quickly. The Real-Time GIS platform consists of a Real-Time GIS engine that is extended from a main memory database system. a middleware which can transfer spatial, aspatial data to clients and receive location data from clients, and a mobile client which operates on the mobile devices. Especially, this paper described the performance evaluation conducted with practical tests if the HBR-tree and the Real-Time GIS engine respectively.

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Genetic Parameters of Pre-adjusted Body Weight Growth and Ultrasound Measures of Body Tissue Development in Three Seedstock Pig Breed Populations in Korea

  • Choy, Yun Ho;Mahboob, Alam;Cho, Chung Il;Choi, Jae Gwan;Choi, Im Soo;Choi, Tae Jeong;Cho, Kwang Hyun;Park, Byoung Ho
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.12
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    • pp.1696-1702
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    • 2015
  • The objective of this study was to compare the effects of body weight growth adjustment methods on genetic parameters of body growth and tissue among three pig breeds. Data collected on 101,820 Landrace, 281,411 Yorkshire, and 78,068 Duroc pigs, born in Korean swine breeder farms since 2000, were analyzed. Records included body weights on test day and amplitude (A)-mode ultrasound carcass measures of backfat thickness (BF), eye muscle area (EMA), and retail cut percentage (RCP). Days to 90 kg body weight (DAYS90), through an adjustment of the age based on the body weight at the test day, were obtained. Ultrasound measures were also pre-adjusted (ABF, EMA, AEMA, ARCP) based on their test day measures. The (co)variance components were obtained with 3 multi-trait animal models using the REMLF90 software package. Model I included DAYS90 and ultrasound traits, whereas model II and III accounted DAYS90 and pre-adjusted ultrasound traits. Fixed factors were sex (sex) and contemporary groups (herd-year-month of birth) for all traits among the models. Additionally, model I and II considered a linear covariate of final weight on the ultrasound measure traits. Heritability ($h^2$) estimates for DAYS90, BF, EMA, and RCP ranged from 0.36 to 0.42, 0.34 to 0.43, 0.20 to 0.22, and 0.39 to 0.45, respectively, among the models. The $h^2$ estimates of DAYS90 from model II and III were also somewhat similar. The $h^2$ for ABF, AEMA, and ARCP were 0.35 to 0.44, 0.20 to 0.25, and 0.41 to 0.46, respectively. Our heritability estimates varied mostly among the breeds. The genetic correlations ($r_G$) were moderately negative between DAYS90 and BF (-0.29 to -0.38), and between DAYS90 and EMA (-0.16 to -0.26). BF had strong $r_G$ with RCP (-0.87 to -0.93). Moderately positive $r_G$ existed between DAYS90 and RCP (0.20 to 0.28) and between EMA and RCP (0.35 to 0.44) among the breeds. For DAYS90, model II and III, its correlations with ABF, AEMA, and ARCP were mostly low or negligible except the $r_G$ between DAYS90 and AEMA from model III (0.27 to 0.30). The $r_G$ between AEMA and ABF and between AEMA and ARCP were moderate but with negative and positive signs, respectively; also reflected influence of pre-adjustments. However, the $r_G$ between BF and RCP remained non-influential to trait pre-adjustments or covariable fits. Therefore, we conclude that ultrasound measures taken at a body weight of about 90 kg as the test final should be adjusted for body weight growth. Our adjustment formulas, particularly those for BF and EMA, should be revised further to accommodate the added variation due to different performance testing endpoints with regard to differential growth in body composition.

Assessment of LCD Color Display Performance Based on AAPM TG 18 Protocol : Decision of Quality Control and Calibration Period (판독용 LCD 컬러 모니터 장치의 성능 평가 - 성능 평가 및 Calibration 주기 결정을 중심으로 -)

  • Lee, Won-Hong;Son, Soon-Yong;Noh, Sung-Soon;Lee, In-Hwa;Kang, Sung-Ho;Lee, Yong-Moon;Park, Jae-Soo;Yoon, Seok-Hwan
    • Journal of radiological science and technology
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    • v.31 no.1
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    • pp.55-60
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    • 2008
  • Purpose: This study is to decide a quality control and calibration period of LCD display devices used for reading diagnostic images. Materias and Methods: The assessment test of 20 flat panel LCD color display devices used for reading diagnostic images were performed based on AAPM TG 18 protocol over the total six sessions at one month intervals from three months after primary calibration, in terms of geometric distortion, reflection test, luminance response evaluation, luminance uniformity, resolution, noise, veiling glare and chromaticity test. Results: The results of geometric distortion, reflection test, luminance uniformity, resolution, noise, veiling glare and chromaticity test were within the criteria recommended by AAPM TG 18, except for luminance response evaluation. In the measured luminance deviation of luminance response evaluation, 4(25%) of 20 display devices were passed a criterion from four months after calibration, and 11 (55%) were passed from eight months. Also in the contrast response of the luminance response evaluation, 1(5%) display device was passed a criterion from four months after calibration, and 3(15%) were passed from eight months. Conclusion: Considering the passing deviation after calibration, the time required and a manpower, the quality control and calibration period of LCD display devices used for reading diagnostic images should be a three months and six months after calibration.

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Effects of Mixture and Systematic Application of Herbicides on Weed Control and Yield in Transplanted Rice (이앙답(移秧畓)에서 제초제(除草劑)의 혼합(混合), 조합처리(組合處理)가 제초효과(除草效果) 및 벼 수량(收量)에 미치는 영향)

  • Kim, J.K.;Ku, Y.C.;Lee, J.H.
    • Korean Journal of Weed Science
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    • v.2 no.1
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    • pp.20-30
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    • 1982
  • A field experiment was conducted in 1981 at the Crop Experiment Station, Suweon, Korea, in machine transplanted paddy rice field, to study the effectiveness of single herbicide, mixture, and systematic application of herbicides on diversity of weed control spectrum. The rice variety planted was Taebaegbyeo, Indica ${\times}$ Japonica cross bred. Experimental field was dominated by Echinochtoa crusgalli, Eleocharis kuroguwai, and Scirpus hotarui, and importance values based on dry weight of these weeds were 89%, 5%, and 3%, respectively. The mixture or systematic treatments of herbicide were generally more effective than single herbicide applications on weed control. Coefficients of similarity based on floristic composition after herbicide application between Perfluidone (5G) and Chloromethoxynil (7G), and between Pertluidone (5G) and Bifenox (7G), and between Perfluidone (5G) and three types of Butachlor (6G) were low, and these sets seemed to be a good mixture herbicide in paddy fields. While, Perfluidone (5G) had low coefficient of similarity with other single herbicides tested. The information on coefficient of similarity could be used as parameter for selecting herbicides to increase the efficiency of herbicidal performance. Simpson's indices from Butachlor (3.5G)/SL-49 (7G), Butachlor (3.5G)/Pyrazolate (6G), and Perfluidone (5G) treatments were high, and these herbicide treatments tended to the weed community type simplified, while the indices from Perfluidone (5G) + Chloromethoxynil (7G), Butachlor (6G) fb Perftuidone (5G), and Butachlor (4G)/Naproanilide (6G) treatments were low, and these herbicide treatments caused to the community type diversified in terms of floristic composition.

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Design and Implementation of Game Server using the Efficient Load Balancing Technology based on CPU Utilization (게임서버의 CPU 사용율 기반 효율적인 부하균등화 기술의 설계 및 구현)

  • Myung, Won-Shig;Han, Jun-Tak
    • Journal of Korea Game Society
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    • v.4 no.4
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    • pp.11-18
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    • 2004
  • The on-line games in the past were played by only two persons exchanging data based on one-to-one connections, whereas recent ones (e.g. MMORPG: Massively Multi-player Online Role-playings Game) enable tens of thousands of people to be connected simultaneously. Specifically, Korea has established an excellent network infrastructure that can't be found anywhere in the world. Almost every household has a high-speed Internet access. What made this possible was, in part, high density of population that has accelerated the formation of good Internet infrastructure. However, this rapid increase in the use of on-line games may lead to surging traffics exceeding the limited Internet communication capacity so that the connection to the games is unstable or the server fails. expanding the servers though this measure is very costly could solve this problem. To deal with this problem, the present study proposes the load distribution technology that connects in the form of local clustering the game servers divided by their contents used in each on-line game reduces the loads of specific servers using the load balancer, and enhances performance of sewer for their efficient operation. In this paper, a cluster system is proposed where each Game server in the system has different contents service and loads are distributed efficiently using the game server resource information such as CPU utilization. Game sewers having different contents are mutually connected and managed with a network file system to maintain information consistency required to support resource information updates, deletions, and additions. Simulation studies show that our method performs better than other traditional methods. In terms of response time, our method shows shorter latency than RR (Round Robin) and LC (Least Connection) by about 12%, 10% respectively.

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Training Needs Analysis for the Roles and Competency of Field Representatives in Electric Work (전기공사 현장대리인의 역할 및 역량에 대한 교육요구분석)

  • Yun, Hyeon Woo;Yoon, Gwan Sik
    • 대한공업교육학회지
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    • v.40 no.1
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    • pp.142-162
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    • 2015
  • The purpose of this study are to provide the basic data materials and implementations for successful performance of electric-work field representatives of South Korean firms by identifying their roles and competency and examining their educational need. For this research purposes, three phased analysis was followed on: (1) the roles of electric-work field representatives, (2) competency of electric-work field representatives and (3) educational need for their competency. This research method was to conduct a focus group interview for 10 expert field representatives along with survey. The collected data materials were processed by MS Excel and SPSS 21.0 for statistical analysis including average, standard deviation and other basic statistics; the gap in awareness of field representatives; and need values. For the needs analysis, the difference between significance of field representatives' competency and current status was examined by t test. And the awareness gap between competency importance and current status was identified based on the Borich equation. The Locus for Focus model was employed herein to identify the kinds of competency with high importance and high inconsistency to prioritize. As a result, this research has found as follows: first, the roles of field representatives were found to be in 13 different kinds of roles. Second, electric-work field representatives were found to need to have 16 different skills. Third, regarding the 16 abilities, the gap between current status and significance was analyzed herein. The results showed statistically significant differences in all cases. The Borich needs analysis found the first required ability was communication ability followed by power of execution, conflict management ability, analytical thinking and time management ability. Also, the results of Locus for Focus model analysis displayed that the first quadrant(HH) included 7 highly-demanded abilities of communication ability, analytical thinking, decision making ability, specialty, time management ability, power of execution and drive for work implementation. The top-priority group was found to have 5 items of communication ability, analytical thinking, time management ability, power of execution and drive for work implementation which were commonly seen in the Locus for Focus model outcomes. Based on these findings, this research could identify the roles and competency of electric-work field representatives and provide the basic data materials applicable to future personal management of electricity companies including recruitment, division of work, job description, evaluation, etc. Also this research offered guidelines on demanded abilities in the field and where to place priority. The kinds of abilities with high educational demand as found in this research must be considered in designing educational programs for the competency building of field representatives. This research is expected to provide useful information in developing such educational programs for field representatives.

Improvements for Atmospheric Motion Vectors Algorithm Using First Guess by Optical Flow Method (옵티컬 플로우 방법으로 계산된 초기 바람 추정치에 따른 대기운동벡터 알고리즘 개선 연구)

  • Oh, Yurim;Park, Hyungmin;Kim, Jae Hwan;Kim, Somyoung
    • Korean Journal of Remote Sensing
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    • v.36 no.5_1
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    • pp.763-774
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    • 2020
  • Wind data forecasted from the numerical weather prediction (NWP) model is generally used as the first-guess of the target tracking process to obtain the atmospheric motion vectors(AMVs) because it increases tracking accuracy and reduce computational time. However, there is a contradiction that the NWP model used as the first-guess is used again as the reference in the AMVs verification process. To overcome this problem, model-independent first guesses are required. In this study, we propose the AMVs derivation from Lucas and Kanade optical flow method and then using it as the first guess. To retrieve AMVs, Himawari-8/AHI geostationary satellite level-1B data were used at 00, 06, 12, and 18 UTC from August 19 to September 5, 2015. To evaluate the impact of applying the optical flow method on the AMV derivation, cross-validation has been conducted in three ways as follows. (1) Without the first-guess, (2) NWP (KMA/UM) forecasted wind as the first-guess, and (3) Optical flow method based wind as the first-guess. As the results of verification using ECMWF ERA-Interim reanalysis data, the highest precision (RMSVD: 5.296-5.804 ms-1) was obtained using optical flow based winds as the first-guess. In addition, the computation speed for AMVs derivation was the slowest without the first-guess test, but the other two had similar performance. Thus, applying the optical flow method in the target tracking process of AMVs algorithm, this study showed that the optical flow method is very effective as a first guess for model-independent AMVs derivation.

A Study on the Attributes determining the Extent of Autonomy in Decision Making for Korean Subsidiaries of Multinational Corporations - Focused on Semiconductor Industry Related Companies - (다국적기업 한국자회사의 의사결정 자율성에 영향을 미치는 요인에 관한 연구 -반도체산업 관련기업체를 중심으로-)

  • Chung, Nak-Kyung;Kim, Hong
    • 한국벤처창업학회:학술대회논문집
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    • 2008.11a
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    • pp.135-168
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    • 2008
  • The Korean semiconductor industry has made a great contribution to growth of Korean economy for the last decades by maintaining a top position in terms of Korean total annual export volume. However, the advanced semiconductor equipment and materials that are used for the production of semiconductor devices still depend on the suppliers from Europe, Japan, and America who have an influential position in the Korean semiconductor industry. The objective of this study is to empirically investigate the attributes determining the extent of autonomy in decision making for the Korean subsidiaries of multinational corporations in the semiconductor industry. This study found there were differences in the extent of autonomy in decision making in terms of the global strategies the multinational corporations pursue. This study surveyed employees at the Korean subsidiaries and joint venture companies of semiconductor multinational corporations and collected 726 survey questionnaires. Several statistical analyses including frequency analysis, reliability analysis, factor analysis, multiple regression analysis and ANOVA were performed using the collected sample data. Based on the analyses, this study found as follow: Firstly, from the factor analysis, this study found Korean subsidiaries faced three sources of uncertainties stemmed from political conditions, competent conditions, demand and supply conditions. The internal resources were characterized by the independencies of production capability, financial capability, marketing capability and human resource management capability. The operational performance was determined by total revenue, net profit and market share growth. Secondly, it was found the uncertainties from political condition and competent condition and the independencies of financial capability and marketing capability partially influenced the extent of autonomy in decision making. The independencies of production capability and human resource management capability significantly influenced the autonomy of decision making in the most areas. It was also found an increase of total revenue, net profit and market share growth partially affected the extent of autonomy in decision making of the Korean subsidiaries. Finally, it was found that the polycentrism of global management by multinational corporations seemed to bring a higher extent of autonomy in decision making than ethnocentrism or geocentrism of global management. Based on the results, this study provided managerial implications regarding the extent of autonomy in decision making for Korean subsidiaries of multinational corporations in order to help management to enhance their business capabilities.

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