• Title/Summary/Keyword: national statistical system

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Thermodynamic Properties of the Polymer Solutions

  • Lee, Woong-Ki;Pak, Hyung- Suk
    • Bulletin of the Korean Chemical Society
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    • v.6 no.6
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    • pp.337-343
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    • 1985
  • A statistical mechanical approach to elucidate the solvent effects on the high polymer solutions has been carried out on the basis of the simple model of liquids improved by Pak. In our works, the partition function of the polymer solutions is formulated by the lattice model and our simple treatment of liquid structures. For the ideal polymer solutions proposed by Flory, thermodynamic functions of the polymer solutions are obtained and equations of mixing properties and partial molar quantities are derived from the presented partition function of the polymer solutions. Partial molar quantities are calculated for the rubber solutions in carbon disulfide, benzene and carbon tetrachloride. Comparisons have been made between our equations and those of Flory's original paper for partial molar properties of the rubber-benzene system. Comparing the experimental data of the osmotic pressure of polystyrene-cyclohexane system with our calculated values and those of Flory's, our values fit to the agreeable degrees better than those of Flory's.

The KMA Global Seasonal Forecasting System (GloSea6) - Part 1: Operational System and Improvements (기상청 기후예측시스템(GloSea6) - Part 1: 운영 체계 및 개선 사항)

  • Kim, Hyeri;Lee, Johan;Hyun, Yu-Kyung;Hwang, Seung-On
    • Atmosphere
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    • v.31 no.3
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    • pp.341-359
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    • 2021
  • This technical note introduces the new Korea Meteorological Administration (KMA) Global Seasonal forecasting system version 6 (GloSea6) to provide a reference for future scientific works on GloSea6. We describe the main areas of progress and improvements to the current GloSea5 in the scientific and technical aspects of all the GloSea6 components - atmosphere, land, ocean, and sea-ice models. Also, the operational architectures of GloSea6 installed on the new KMA supercomputer are presented. It includes (1) pre-processes for atmospheric and ocean initial conditions with the quasi-real-time land surface initialization system, (2) the configurations for model runs to produce sets of forecasts and hindcasts, (3) the ensemble statistical prediction system, and (4) the verification system. The changes of operational frameworks and computing systems are also reported, including Rose/Cylc - a new framework equipped with suite configurations and workflows for operationally managing and running Glosea6. In addition, we conduct the first-ever run with GloSea6 and evaluate the potential of GloSea6 compared to GloSea5 in terms of verification against reanalysis and observations, using a one-month case of June 2020. The GloSea6 yields improvements in model performance for some variables in some regions; for example, the root mean squared error of 500 hPa geopotential height over the tropics is reduced by about 52%. These experimental results show that GloSea6 is a promising system for improved seasonal forecasts.

Performance Analysis of Auto Body Manufacturing System using ARENA Simulation (ARENA 시뮬레이션을 이용한 차제공장 수행도 분석)

  • Jung, Jae-Ho;Kim, Hyun-Gun;Kim, Hyang-He;Jeon, Tae-Bo
    • Journal of Industrial Technology
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    • v.20 no.A
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    • pp.229-238
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    • 2000
  • Simulation analysis for an auto body manufacturing system has been performed in this study. The major goal is to figure out the condition yielding the production rate, 70 per hour. It is, however, very difficult to maintain this rate due to inherent system factors such as machine failure rates, machine repair rates, number of carriers between manufacturing lines(shops), carrier speed etc. We first carefully examined the system and developed a simulation model using ARENA. We then applied statistical experimental design concepts for performance analysis. Our results indicate that the buffer size of 30 and quick repair of failed robots are required for the desired production rate. Other factors, on the other hand, are seen to have minor effects on the throughput. The approach taken in this study and the results obtained may provide a practical guideline for performance analysis and thus be applied without trepidation for similar cases.

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Reliability Estimation in Bivariate Pareto Model with Bivariate Type I Censored Data

  • Cho, Jang-Sik;Cho, Kil-Ho;Kang, Sang-Gil
    • 한국데이터정보과학회:학술대회논문집
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    • 2003.10a
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    • pp.31-38
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    • 2003
  • In this paper, we obtain the estimator of system reliability for the bivariate Pareto model with bivariate type 1 censored data. We obtain the estimators and approximated confidence intervals of the reliability for the parallel system based on likelihood function and the relative frequency, respectively. Also we present a numerical example by giving a data set which is generated by computer.

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Speech Emotion Recognition using Feature Selection and Fusion Method (특징 선택과 융합 방법을 이용한 음성 감정 인식)

  • Kim, Weon-Goo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.66 no.8
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    • pp.1265-1271
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    • 2017
  • In this paper, the speech parameter fusion method is studied to improve the performance of the conventional emotion recognition system. For this purpose, the combination of the parameters that show the best performance by combining the cepstrum parameters and the various pitch parameters used in the conventional emotion recognition system are selected. Various pitch parameters were generated using numerical and statistical methods using pitch of speech. Performance evaluation was performed on the emotion recognition system using Gaussian mixture model(GMM) to select the pitch parameters that showed the best performance in combination with cepstrum parameters. As a parameter selection method, sequential feature selection method was used. In the experiment to distinguish the four emotions of normal, joy, sadness and angry, fifteen of the total 56 pitch parameters were selected and showed the best recognition performance when fused with cepstrum and delta cepstrum coefficients. This is a 48.9% reduction in the error of emotion recognition system using only pitch parameters.

Defect Recognition with Statistical Distributions of PD in Solid Insulation (고체절연 시스템에서 부분방전의 통계적 분포를 이용한 결함의 인식)

  • Park, J.N.;Kim, J.P.;Park, Y.G.;Jang, D.U.;Lim, K,J.
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.1930-1932
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    • 2000
  • PD in defects of solid insulation system is very harmful since it leads to deteriorate insulation system by. the discharge electrons and ions bombarding the insulation surface and the action of chemical products that are formed by discharges. PD is used to detect and recognize defects and degradation of insulation system However, there are still marked difficulties to recognize defects by PD methode. In this paper, we investigated properties of PD of defects in solid insulation by using statical methods and classified PD patterns of surface discharge, electrical tree and void discharge with source of discharge, we used specific distributions such as $H_n(q)$, $H_{an}(\phi)$, $H_n(\phi)$, $H_a(\phi)$ to recognize defects of solid insulation system.

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Effective Manufacturing Operation based on Simulation (시뮬레이션을 이용한 공정운영 효율화)

  • Jeon, Tae Bo;Jin, Min-Ji
    • Journal of Industrial Technology
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    • v.31 no.A
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    • pp.3-9
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    • 2011
  • Simulation plays an important role for system analysis. In this study, a manufacturing system has been analyzed through computer simulation. We first briefly explain the considered system with prevailing problems. We then build a simulation model using ARENA simulation language. Based on two selected performance measures, material transporter load and hourly throughput, explicit system analyses have been performed. We addressed four parameters - variation of the processing time, number of raw material transporters, quality failure rate, and machine failures - as the input parameters affecting the output measures selected. We adopted Taguchi's orthogonal array in statistical experimental design and drew meaningful results from the analysis. The results given in the study may provide a good guidance for practical applications.

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An Investigation of Classification and Management of Emergency Restoration Equipment (응급복구장비의 분류와 운용방안 연구)

  • Kim, Jung-Soo;Yoon, Young-Noh;Kim, Nak-Seok;Yoon, Sei-Eui
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.605-608
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    • 2008
  • Storm and flood damage management systems in national disaster management system(NDMS) were organized into three operation systems. They are prevention, preparation, response, and recovery systems. Disaster resources in each system must be promptly and exactly applied to minimize casualties and loss of properties. However, the disaster resources in current management system can not be immediately used in calamity situation due to the lack of efficiency in statistical data. Therefore, it is necessary to classify the emergency restoration equipment for efficient management and mobilization of disaster resources in disaster situation. In this study, field survey was executed to appropriately classify the emergency restoration equipment. Problems and reformation points of the disaster resources system were also presented to improve the classification technique and to construct the data base.

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WEB FRONT-END COMPUTING RELATIONAL DATABASE SYSTEM FOR ITEM-LEVEL PRELIMINARY HIGHWAY COST ESTIMATES

  • Jui-Sheng Chou ;James T. O'Connor ;Khali R. Persad ;Wai Kiong Chong
    • International conference on construction engineering and project management
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    • 2005.10a
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    • pp.509-514
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    • 2005
  • In recent years, use of the web technologies and on-line process has immensely swapped single-user platform practice. This study attempted to develop preliminary cost estimating program by means of Web technologies based on statistical modeling results. A prototype Web-based Preliminary Item-Level Cost Estimating System (WBPILCES) using open source software was developed as an on-line estimating tool in this research. The primary objective is to study the possible flexibility of implementing a centralized information system that will be maintained by the Texas Department of Transportation (TxDOT) IT division. The full-scale deployment of proposed information architecture is expected to seamlessly integrate with legacy database system currently used by TxDOT so as to streamline data storage, cost growth tracking and estimates documentation.

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Large Sample Test for Independence in the Bivariate Pareto Model with Censored Data

  • Cho, Jang-Sik;Lee, Jea-Man;Lee, Woo-Dong
    • Journal of the Korean Data and Information Science Society
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    • v.14 no.2
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    • pp.377-383
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    • 2003
  • In this paper, we consider two components system in which the lifetimes follow the bivariate Pareto model with random censored data. We assume that the censoring time is independent of the lifetimes of the two components. We develop large sample tests for testing independence between two components. Also we present simulated study which is the test based on asymptotic normal distribution in testing independence.

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