• Title/Summary/Keyword: Sampled-data system

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A Study on Logistics Information Characteristic Influencing Logistics Performance (물류성과에 영향을 미치는 물류정보특성에 관한 연구)

  • Ha, Chang-Seung;Jung, Lee-Sang
    • Journal of Fisheries and Marine Sciences Education
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    • v.19 no.1
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    • pp.74-83
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    • 2007
  • These days business logistics has become one of the very important factors of logistics cost reduction and customer service satisfaction. In order to control business logistics more effectively, many companies must be concerned about logistics performance.This study aims at analyzing information system characteristic and logistics performance. The information system characteristic variables are considered IS resource, IS strategic role. The logistics performance variables are considered logistic cost, customer service.For data on the 301 sampled company, a mail survey using a questionnaire was conducted in this study. The following results were obtained.First, IS characteristic variables were significant for logistics performance. Specially, efficient management of IS manpower and IS planning, present IS were significant for logistics performance. Second, there also were IS manpower and IS planning, present IS that indentifing high logistics performance group and low logistics performance group.

Application of compressive sensing and variance considered machine to condition monitoring

  • Lee, Myung Jun;Jun, Jun Young;Park, Gyuhae;Kang, To;Han, Soon Woo
    • Smart Structures and Systems
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    • v.22 no.2
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    • pp.231-237
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    • 2018
  • A significant data problem is encountered with condition monitoring because the sensors need to measure vibration data at a continuous and sometimes high sampling rate. In this study, compressive sensing approaches for condition monitoring are proposed to demonstrate their efficiency in handling a large amount of data and to improve the damage detection capability of the current condition monitoring process. Compressive sensing is a novel sensing/sampling paradigm that takes much fewer data than traditional data sampling methods. This sensing paradigm is applied to condition monitoring with an improved machine learning algorithm in this study. For the experiments, a built-in rotating system was used, and all data were compressively sampled to obtain compressed data. The optimal signal features were then selected without the signal reconstruction process. For damage classification, we used the Variance Considered Machine, utilizing only the compressed data. The experimental results show that the proposed compressive sensing method could effectively improve the data processing speed and the accuracy of condition monitoring of rotating systems.

A Study on Korean Agricultural Extension Officers' Perception of Role Ambiguity According to Restructuring of Agricultural Administrative Systems (농촌지도조직체계의 변화에 따른 농촌지도공무원의 역할모호성에 대한 인식)

  • Ju, Dae-Jin;Kim, Jin-Mo
    • Journal of Agricultural Extension & Community Development
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    • v.19 no.2
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    • pp.211-240
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    • 2012
  • The purpose of this study was to identify korean agricultural extension workers' Perception of role ambiguity according to restructuring of Agricultural Administrative Systems. The target population of this study was selected from 21 centers out of 156 centers. The subjects for study were 728 agricultural extension officers by the cluster sampling drawn from the sampled 21 agricultural extension centers in four clusters. A survey questionnaire was utilized to measure variables of this study. It consisted of role ambiguity scale and demographic items. In this study, role ambiguity scale was translated from the existing scale. Through a pilot test and final survey, reliability and validity of these scales were examined. The data were collected by mail. A total 420 questionnaires out of 728 from 21 agricultural extension centers were returned. After data cleaning, 410 responses were used for analysis. Both descriptive and inferential statistics were applied for data analysis. Major findings of the study were as follows. There were significant differences of the degree of role ambiguity among the local extension workers divided by four clusters. Especially, the degree of role ambiguity of restructured local administrative system were more higher than other clusters, comparatively. Thus, the factors causing the role ambiguity to agricultural extension officers need to be measured it in-depth.

Noise Reduction Method for Particle Measurement System using Beta-ray Absorption Method (베타선 흡수법을 이용하는 미세먼지 측정시스템을 위한 잡음제거 방법)

  • Choi, Hun;Sohn, Sang-Wook;Bae, Hyeon-Deok
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.11
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    • pp.1706-1712
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    • 2012
  • The Beta-ray absorption method (BAM) gives a good solution for measuring the mass concentration of atmospheric particles(PM10 and PM2.5). To determine particular matters (PM) concentration, a ratio of the number of detected beta-ray intensity passing through the clean filter and the dust-sampled filter is used. These intensity data measured in air pollution monitoring such as PM10 and PM2.5 usually contained the additive noise(thermal noise, power supply noise and etc.). Therefore, the estimation performance of mass concentration can be deteriorated by these noises. In this paper, we present a new noise reduction method that is essentially required to develope an automatic continuous PM monitoring system using beta-ray absorption method. By combining the block data averaging technique and curve fitting, in the proposed method, the additive noise can be reduced in the measured data. To evaluate the performance of the proposed method, computer simulations were performed with computer generated signals as the input.

Investigations of the Potential Fisheries Resources in the Southern Waters of Korea - Hydroacoustic Investigations of Abundance and Distributing of Fish - (한국 남해안의 잠재어업자원 조사연구 - 어업생물자원의 음향학적 조사 -)

  • Lee, Dae-Jae;Kim, Jin-Geon;Sin, Hyeong-Ho
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.34 no.3
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    • pp.259-273
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    • 1998
  • The hydroacoustic surveys to provide the essential information for the assessment, management and utilization of fishery resources in the southern waters of Korea were carried out during five research cruises between October 1996 and October 1997 by the training ship KAYA of Pukyong National University. These hydroacoustic investigations were designed to obtain more precise estimates of the geographic distribution, absolute abundance and biological characteristics of the fishery resources, and the vertically integrated densities of fish in terms of volume backscattering strength(SV) by survey region and depth bins, such as the entire water column and the 0~ 10 m from bottom fraction, were measured separately. Hydroacoustic data were collected by using a Simrad EK 500 Scientific echo sounder operating at two frequencies of 38kHz and 120kHz and the data stored in field were later processed on a HP PC using a Simrad EP 500 echo integration and target strength analysis system. The biological compositions of echo signal were identified and sampled using a demersal trawl during daylight hours. The mean target strength to scale the echo integration data for hydroacoustic surveys was derived from the relationship between the SV and the weight of trawl catch per unit volume of the water column sampled by demersal trawls. The results obtained can be summarized as follow : 1. The mean volume backscattering strength for the entire water column in the southern waters of Korea between 1996 and 1997 were -67.2 dB and -70.9 dB at two frequencies of 38 kHz and 120 kHz , respectively, and for the bottom layer of the 0-10 m from bottom friction were -68.8 dB, -70.2 dB, respectively. That is, the volume backscattering strength for the entire water column at low frequency was higher than that at high frequency. 2. The relationship between the mean backscattering strength (〈SV〉, dB) for the depth strata of trawl hauls and the weight (C, kg/m3) per cubic meter of the catch sampled by bottom trawling in the southern waters of Korea in January and July 1997 were expressed by the following equations: 38 kHz : 〈SV〉= -28.2 + 10 log(C), 120 kHz : 〈SV〉= -32.4 + 10 log(C). The mean weight -normalized target strengths derived from these equitions were -28.2 dB/ kg, -32.4 dB/ kg at 38 kHz and 120 kHz , respectively. That is, the mean weight -normalized target strength at 38 kHz was 4.2 dB higher than that at 120 kHz. 3. The distribution density of fish in terms of biomass per unit volume in the southern waters of Korea were estimated to be 125.9 $\times$ 10-6 kg/m3 and 141.3 $\times$ 10-6 kg/m3 at 38 kHz and 120 kHz , respectively.

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A Study on Feature Information Parsing System of Video Image for Multimedia Service (멀티미디어 서비스를 위한 동영상 이미지의 특징정보 분석 시스템에 관한 연구)

  • 이창수;지정규
    • Journal of Information Technology Applications and Management
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    • v.9 no.3
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    • pp.1-12
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    • 2002
  • Due to the fast development in computer and communication technologies, a video is now being more widely used than ever in many areas. The current information analyzing systems are originally built to process text-based data. Thus, it has little bits problems when it needs to correctly represent the ambiguity of a video, when it has to process a large amount of comments, or when it lacks the objectivity that the jobs require. We would like to purpose an algorithm that is capable of analyze a large amount of video efficiently. In a video, divided areas use a region growing and region merging techniques. To sample the color, we translate the color from RGB to HSI and use the information that matches with the representative colors. To sample the shape information, we use improved moment invariants(IMI) so that we can solve many problems of histogram intersection caused by current IMI and Jain. Sampled information on characteristics of the streaming media will be used to find similar frames.

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Neuro-Fuzzy Diagnostic Technique for Performance Evaluation of a Chiller (뉴로 퍼지를 이용한 냉동기 성능 진단 기법)

  • Shin, Young-Gy;Chang, Young-Soo;Kim, Young-Il
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.27 no.5
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    • pp.553-560
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    • 2003
  • On-site diagnosis of chiller performance is an essential step fur energy saving business. The main purpose of the on-site diagnosis is to predict the COP of a target chiller. Many models based on thermodynamics background have been proposed for this purpose. However, they have to be modified from chiller to chiller and require deep insight into thermodynamics that most of field engineers are often lacking in. This study focuses on developing an easy-to-use diagnostic technique that is based on adaptive neuro-fuzzy inference system (ANFIS). Quality of the training data for ANFIS, sampled over June through September, is assessed by checking COP prediction errors. The architecture of the ANFIS, its error bounds, and collection of training data are described in detail.

Prediction of Vapor-Compressed Chiller Performance Using ANFIS Model (냉동기 성능 진단을 위한 적응형 뉴로퍼지(ANFIS) 모델 개발)

  • Shin, Young-Gy;Chang, Young-Soo;Kim, Young-Il
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.89-95
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    • 2001
  • On-site diagnosis of chiller performance is an essential step for energy saving business. The main purpose of the on-site diagnosis is to predict the COP of a target chiller. Many models based on thermodynamics background have been proposed for the purpose. However, they have to be modified from chiller to chiller and require deep insight into thermodynamics that most of field engineers are often lacking in. This study focuses on developing an easy-to-use diagnostic technique that is based on adaptive neuro-fuzzy inference system (ANFIS). Quality of the training data for ANFIS, sampled over June through September, is assessed by checking COP prediction errors. The architecture of the ANFIS, its error bounds, and collection of training data are described in detail.

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A Study on the Speech Recognition using Advanced Competitive Learning (개선된 경쟁학습을 이용한 음성인식)

  • Song, Joon-Gyu;Lee, Dong-Wook;Kim, Young-T.
    • Proceedings of the KIEE Conference
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    • 1997.11a
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    • pp.594-596
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    • 1997
  • This paper presents the speaker-dependent Korean isolated digit recognition system using advanced competitive learning. Since competitive learning algorithms are easy and simple to implement, they are used in various fields. The proposed recognition algorithm consists of three procedures: comparing winning number of codebook vectors, selecting the representative vector out of codebook vectors, and generating a new codebook with the representative vectors. In this paper, we use a sound blaster 16 for obtaining speech data. Speech data are sampled by 16 bits and 11 kHz sampling rate.

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A study on the microcomputer aided pressure progress measurement and combustion analysis in engine cylinder (Micro-Computer를 이용한 기관 실린더 내의 압력측정 및 연소해석에 관한 연구)

  • 김희년;김시범;하종율
    • Journal of the korean Society of Automotive Engineers
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    • v.10 no.3
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    • pp.45-50
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    • 1988
  • The measurement system of the pressure in engine cylinder is developed with the aids of the microcomputer, A/D converter and simple electrical circuits. The experiment is performed in 4 cycle single cylinder Gasoline engine. When data for the pressure progress is sampled, clock signal or signal from the crank angle is used as trigger. The variation of the pressure during the cycles can be well obtained experimentally. So, the informations which are necessary in the combustion analysis, i.e. expansion pressure, indicated mean effective pressure, the magnitude and time of the maximum pressure ignition time, the rate of pressure rise and heat release and combustion rates can be obtained by the calculation using experimental data. Also, the informations about the after-burning process, the existence of the detonation waves and end time of combustion can be investigated from this study.

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