• 제목/요약/키워드: effective-medium model

검색결과 304건 처리시간 0.027초

87C51을 이용한 분산처리 감시 및 제어 시스템의 설계에 관한 연구 (A Study on the Design of Monitoring and Control System Using 87C51 Microprocessor)

  • 홍순철;정경열
    • 연구논문집
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    • 통권24호
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    • pp.129-140
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    • 1994
  • Design and implementation of monitoring and control system using dual-microprocessor node is presented for real time process. The proposed system is implemented with 2 of the single chip microprocessors in tightly coupled mode and results in speed up of $s_p=1.74.$ Under the assumption that the nodes are interconnected in multidrop. the overall system performance such as average throughout-delay characteristics and effective throughput are analyzed using M/G/1 gueueing model, and results show that the proposed node can be used to medium sized distributed monitoring and control system.

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클라우드 환경에서의 비용 효율적인 맵리듀스 처리 (Cost-Effective MapReduce Processing in the Cloud)

  • 류우석
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2018년도 추계학술대회
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    • pp.114-115
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    • 2018
  • 본 논문에서는 클라우드 환경에서 빅데이터를 비용 효율적으로 분석하기 위한 기법을 연구한다. 전자의무기록의 클라우드 저장이 최근 가능해짐에 따라 중소병원에서의 클라우드 기반 빅데이터 분석 요구가 증가하고 있다. 이에 본 논문에서는 대중적으로 많이 사용되고 있는 아마존 EMR 프레임워크를 분석하고, EMR 환경에서 비용 효율적으로 빅데이터를 분석하기 위한 비용 모델을 제안한다. 제안한 기법을 적용하면 클러스터 비용 대비 처리시간이 가장 효율적인 클러스터 규모를 계산할 수 있으므로, 보다 적은 비용으로 빅데이터 분석을 효과적으로 처리할 수 있다.

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The Effect of Some Physical Parameters on Saturation and Velocity Profiles in a Porous Medium

  • Ghyym S. H.
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 1997년도 추계 학술대회논문집
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    • pp.120-125
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    • 1997
  • In the present work the influence of various physical parameters on the two-phase flow behavior in a self-heated porous medium has been studied using a numerical model, that is, the effects of heat generation rate, of porosity, of particle size, and of system pressure on the dryout process. To analyze the effect of these parameters, the variation of both liquid volumetric fraction (i.e., liquid saturation) and liquid axial velocity is evaluated at the steady state or at the onset of a first boiled-out region. The analysis of computational results indicate that a qualitative tendency exists between the parameters such as heat generation rate, porosity, effective particle diameter and the temporal development of the liquid volumetric fraction field up to dryout. In addition to these parameters, a variation of fluid properties such as phase density, phase viscosity due to a change of system pressure can be used for gaining insight into the nature of two-phase flow behavior up to dryout.

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Dynamic buckling response of temperature-dependent functionally graded-carbon nanotubes-reinforced sandwich microplates considering structural damping

  • Shokravi, Maryam;Jalili, Nader
    • Smart Structures and Systems
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    • 제20권5호
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    • pp.583-593
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    • 2017
  • This research deals with the nonlocal temperature-dependent dynamic buckling analysis of embedded sandwich micro plates reinforced by functionally graded carbon nanotubes (FG-CNTs). The material properties of structure are assumed viscoelastic based on Kelvin-Voigt model. The effective material properties of structure are considered based on mixture rule. The elastic medium is simulated by orthotropic visco-Pasternak medium. The motion equations are derived applying Sinusoidal shear deformation theory (SSDT) in which the size effects are considered using Eringen's nonlocal theory. The differential quadrature (DQ) method in conjunction with the Bolotin's methods is applied for calculating resonance frequency and dynamic instability region (DIR) of structure. The effects of different parameters such as volume percent of CNTs, distribution type of CNTs, temperature, nonlocal parameter and structural damping on the dynamic instability of visco-system are shown. The results are compared with other published works in the literature. Results indicate that the CNTs have an important role in dynamic stability of structure and FGX distribution type is the better choice.

몰입감 있는 맞춤형 가상 모델하우스 (Immersive Virtual Custom-made Model House)

  • 황선욱;김영미;서용원;고광희;류제하;이관행;이용구
    • 한국CDE학회논문집
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    • 제13권1호
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    • pp.8-17
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    • 2008
  • Putting a high value on individual preferences is a modern trend that more and more companies are considering for their product design and development and the apartment design is not an exception. Most apartments today are built using similar design with no room for customization. People in general want their tastes to be reflected in the design of their apartment. However, delivering what customers like to the construction company may not be an easy task in practice. For this reason, an intuitive and effective medium between the company and customers for effective communication is needed to ameliorate such a difficulty and in response to this necessity, we developed a test platform for the virtual model house which provides a user with the customization of the apartment using haptic interactions. In our virtual environment, a user can explore an apartment and change the interior based on their taste and feel through intuitive haptic interactions.

BPR 방법론에 기반한 중소 PCB 제조업체의 MES 구축 전략과 효과분석 (Implementation Strategy and Effect Analysis of MES for a Small and Medium PCB Production Company based on BPR Methodology)

  • 김건연;진유의;노상도;최상수;조용주;최석우
    • 산업공학
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    • 제24권3호
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    • pp.231-240
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    • 2011
  • Manufacturing enterprises have been doing their best endeavors to obtain competitiveness using various methodologies, such as information technology. In order to achieve competitiveness, they are adopting manufacturing execution system (MES). MES is a total management system that manages from the beginning of the production by product order until the quality inspection of the finished product. And MES is an inter-mediator for supplementation of information gap between ERP and inspection machine and equipment. This paper describes on establishment of effective strategy based on BPR methodology and implementation of MES small and medium PCB manufacturing company with multiple-types of products and mixed process flows. And then we proposed evaluation model based on balanced score card (BSC) for considering non-finance elements as well as finance elements. With evaluation model, we analyzed benefits and effects of MES.

ERP시스템을 이용한 자동차부품 제조업의 효율적인 가용재고관리 프로세스에 대한 표준화 모델 개발 및 효과분석 (Standardization Model Development and its Effect Analysis for Effective Available Stock Management Process of Automobile Parts Manufacturing Industry using the ERP System)

  • 윤경배
    • 한국컴퓨터정보학회논문지
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    • 제16권2호
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    • pp.279-288
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    • 2011
  • 본 연구는 자동차부품제조업의 전사적 자원관리(ERP : Enterprise Resource Planning)시스템 전체 모듈중 가용재고관리 프로세스에 대한 표준화 모델을 개발한다. 표준화 모델은 중소기업청 및 중소기업기술정보진흥원에서 제시한 정보화구축 개발 방법론에 준하여 단계별 방법론에 따라 시스템이 구축되게 된다. 표준화 모델은 가용 재고관리 프로세스를 위한 발주관리, 입고관리, 출고관리, 재고관리의 프로세스를 표준화 시키고 표준모듈을 개발한다. 본 연구로 ERP시스템 하에서 가용재고관리 프로세스를 구축하고자 하는 제조기업 및 관련 전문 IT업체 들이 표준화된 모듈을 적용하여 시스템을 보다 효과적으로 구축 할 수 있으며, 시스템에 대한 구축 용이성과 신뢰성을 제공한다. 본 연구 결과를 적용함으로써 기업의 원자재 및 제품의 과다보유를 방지하고 적정, 안전재고를 항시 보유할 수 있으며 실시간 재고파악, 고객납기 준수, 과다제품 생산 방지 및 재고비용 절감 등이 가능하다.

장기만연속수수량추정모형의 실용화 연구 -우리나라 중소유역을 대상으로- (A Generalized Model on the Estimation of the Long - term Run - off Volume - with Special Reference to small and Medium Sized Catchment Areas-)

  • 임병현
    • 한국농공학회지
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    • 제32권4호
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    • pp.27-43
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    • 1990
  • This study aimed at developing a generalized model on the estimation of the long - term run - off volume for practical purpose. During the research period of last 3 years( 1986-1988), 3 types of estimation model on the long - term run - off volume(Effective rainfall model, unit hydrograph model and barne's model for dry season) had been developed by the author. In this study, through regressional analysis between determinant factors (bi of effective rainfall model, ai of unit hydrograph model and Wi of barne's model) and catchment characteris- tics(catchment area, distance round the catchment area, massing degree coefficient, river - exte- nsion, river - slope, river - density, infiltration of Watershed) of 11 test case areas by multiple regressional method, a new methodology on the derivation of determinant factors from catchment characteristics in the watershed areas having no hydrological station was developed. Therefore, in the resulting step, estimation equations on run - off volume for practical purpose of which input facor is only rainfall were developed. In the next stage, the derived equations were applied on the Kang - and Namgye - river catchment areas for checking of their goodness. The test results were as follows ; 1. In Kang - river area, average relative estimation errors of 72 hydrographs and of continuous daily run - off volume for 245 days( 1/5/1982 - 31/12) were calculated as 6.09%, 9.58% respectively. 2. In Namgye - river area, average relative estimation errors of 65 hydrographs and of conti- nuous daily run - off volume for 2fl days(5/4/1980-31/12) were 5.68%, 10.5% respectively. In both cases, relative estimation error was averaged as 7.96%, and so, the methodology in this study might be hetter organized than Kaziyama's formula when comparing with the relative error of the latter, 24~54%. However, two case studies cannot be the base materials enough for the full generalization of the model. So, in the future studies, many test case studies of this model should he carries out in the various catchment areas for making its generalization.

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중소기업의 소셜미디어에 대한 인식이 활용의도 및 실제 활용에 미치는 영향 - 기업특성의 조절효과를 중심으로 - (Impacts of Small and Medium Enterprises' Recognition of Social Media on Their Behavioral Intention and Use Behavior)

  • 이정우;김은홍
    • 한국IT서비스학회지
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    • 제14권1호
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    • pp.195-215
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    • 2015
  • Recently, as the number of smart-phone users has been rapidly increased, enterprise managers have a keen interest in business application of social media. Most previous studies have focused on perspective of the individual unit of analysis instead of enterprise level unit. The study is focused on the relationship between the enterprises' recognition and behavioral intention (and use) about social media application. The purpose of this study is to develop the model of small and medium enterprises' social media application, and to find the factors affecting their behavioral intention or use behavior. The moderating effects of four corporate characteristics on the relationship between the enterprises' recognition and behavioral intention are also examined. We surveyed 900 corporate staffs and received 203 responses. After questionnaires with unreliable responses had been excluded, 182 effective samples were used in the final analysis. The findings suggest that Performance Expectation, Social Influence, Facilitating Conditions significantly affect Behavioral Intention of social medea, and Behavioral Intention affects USE. Furthermore, some corporate characteristics have moderating effect on the relationship between recognition of social media and Behavioral Intention.

Effect of Managerial Skills on the Performance of Small- and Medium-Sized Enterprises: A Case Study in Pakistan

  • AHMAD, Israr;AHMAD, Shuhymee Bin
    • The Journal of Asian Finance, Economics and Business
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    • 제8권4호
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    • pp.161-170
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    • 2021
  • The study aims to investigate the mediating effect of strategic planning on the relationship between managerial skills and the performance of small- and medium-sized enterprises (SMEs) in Punjab, Pakistan. Stratified proportionate probability sample method was used to select the 265 SMEs. The study applied a structural equation model (SEM) to analyze the proposed research hypotheses by using PLS-SEM. This research examines the direct and indirect effects of strategic planning on the performance of SMEs using the SEM test. The results indicate the positive effect of managerial skills on SMEs' performance and also suggested that strategic planning mediates the relationship between managerial skills and SMEs' performance. In addition, the role of managerial skills on the usage of the company's resources is highly influential through strategic planning. Strategic planning has been found to impact significantly and positively on the relationship between managerial skills and performance of SMEs in Punjab, Pakistan. The findings suggested that, in devising appropriate strategies for SMEs, the effect of managerial skills on the utilization of the firm's resources can be more effective to the firm's performance. In short, the utilization of a firm's resources through a proper planning is more essential for the sustainability of SMEs.