• 제목/요약/키워드: Technical change

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Predicting the high temperature effect on mortar compressive strength by neural network

  • Yuzer, N.;Akbas, B.;Kizilkanat, A.B.
    • Computers and Concrete
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    • 제8권5호
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    • pp.491-510
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    • 2011
  • Before deciding if structures exposed to high temperature are to be repaired or demolished, their final state should be carefully examined. Destructive and non-destructive testing methods are generally applied for this purpose. Compressive strength and color change in mortars are observed as a result of the effects of high temperature. In this study, ordinary and pozzolan-added mortar samples were produced using different aggregates, and exposed to 100, 200, 300, 600, 900 and $1200^{\circ}C$. The samples were divided into two groups and cooled to room temperature in water and air separately. Compression tests were carried out on these samples, and the color change was evaluated by the Munsell Color System. The relationships between the change in compressive strength and color of mortars were determined by using a multi-layered feed-forward Neural Network model trained with the back-propagation algorithm. The results showed that providing accurate estimates of compressive strength by using the color components and ultrasonic pulse velocity design parameters were possible using the approach adopted in this study.

공공병원과 민간병원의 생산성 격차 비교 (The Comparison of Productivity Change Gap of Public Hospitals and Private Hospitals in Korea)

  • 양동현
    • 디지털융복합연구
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    • 제11권10호
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    • pp.203-215
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    • 2013
  • 본 연구는 대한병원협회의 경영실적 통계자료에서 2007년부터 2011년까지 5년간 공공종합병원과 민간종합병원의 패널자료를 추출하여 공공종합병원과 민간종합병원의 부트스트랩 메타맘퀴스트 생산성 지수를 산출하고 이 지수를 분해하여 생산성 변화와 생산성 격차를 분석하였다. 분석한 결과와 시사점을 정리하면 다음과 같다. 첫째, 공공병원그룹의 메타효율성이 민간병원그룹에 비해 높으나 기술격차비율은 민간병원그룹이 공공병원그룹에 비해 높으며 프론티어에 가장 가까워 민간병원그룹의 소수 대형종합병원이 전체 종합병원의 선도적 역할을 수행하고 있었다. 둘째, 그룹별 생산성 증가는 민간병원그룹이 공공병원그룹에 비해 높았는데, 이는 프론티어의 이동효과($FCU^k$)보다는 기술추격에 기인하는 것으로 분석되었다. 그러나 민간병원그룹과 공공병원그룹 간 기술효율성, 생산성 변화와 생산성 격차가 통계적으로 의미 있는 차이를 보이지 않는 것으로 확인하였다. 따라서 공공병원이 환자 진료실적 측면에서 민간병원 수준의 기술효율성과 생산성 변화 및 생산성 격차를 보임에 따라 공공병원이 환자진료실적 측면에서 공공병원으로서 기능과 역할을 수행하는 것으로 판단된다. 그러므로 재정적 측면에서 어려움을 겪는 공공병원이 선두적인 민간병원과의 연계를 통하여 의료기술과 경영기술을 습득하고 공유하는 것이 필요하다는 시사점을 제공한다.

모수적․비모수적 기법을 활용한 베트남 공공종합병원의 규모수익과 생산효율성 변화 분석 (Analysis on RTS and the Change of Productivity Efficiency of Public General Hospitals in Vietnam using Parametric and Non-Parametric Approach)

  • 양동현
    • 한국산학기술학회논문지
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    • 제15권2호
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    • pp.767-776
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    • 2014
  • 본 연구는 베트남 호치민시 보건부 데이터베이스에서 추출한 20개 공공종합병원의 2006년부터 2010년까지 5년간 패널자료를 이용하여 비모수적 기법과 모수적 기법을 활용하여 규모수익과 생산성 변화를 측정하였다. 그 결과를 요약하면 다음과 같다. 첫째, 비모수 기법으로 측정된 생산성 증가율은 5년간 누적 증가율이 2.8%이며 이는 5.8%의 기술효율성 증가와 기술효율성 개선에 기인하고 있다. 반면 규모효율성은 5.2% 감소하고 있다. 둘째, 모수적 기법으로 측정한 생산성은 17.1% 감소를 보였으며 이는 17.1%의 기술 퇴보와 9.1%의 규모효율성 감소에 기인하고 있다. 두 기법에서의 공통적인 점은 베트남 공공종합병원에서 규모의 비효율성이 발생하고 있으며 규모의 비효율성 변화가 생산성 변화에 중요한 영향을 미치고 있었다. 즉 베트남 공공종합병원은 분석표본의 70%~80%가 규모의 체증상태에 있으며 이는 환자 수에 비해 공공병원의 규모가 과잉공급 상태에 있음을 시사하고 있다. 이 연구는 베트남 공공병원의 효율성과 생산성 변화를 측정한 국내 첫 연구이며 향후 베트남 병원산업 진출을 위한 기초 정보로 활용될 수 있다는 점에서 의미가 있다.

모델예측제어 기법을 이용한 제지공정에서의 지종교체 제어 (Control of Grade Change Operations in Paper Plants Using Model Predictive Control Method)

  • 김도훈;여영구;박시한;강홍
    • 펄프종이기술
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    • 제35권4호
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    • pp.48-56
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    • 2003
  • In this work an integrated model for paper plants combining wet-end and dry section is developed and a model predictive control scheme based on the plant model is proposed. Closed-loop process identification method is employed to produce a state-space model. Thick stock, filler flow, machine speed and steam pressure are selected as input variables and basis weight, ash content and moisture content are considered as output variables. The desired output trajectory is constructed in the form of 1st-order dynamics. Results of simulations for control of grade change operations are compared with plant operation data collected during the grade change operations under the same conditions as in simulations. From the comparison, we can see that the proposed model predictive control scheme reduces the grade change time and achieves stable steady-state.

중소기업 기술혁신이 기술개발과 생산단계에 미치는 영향 실태분석 (Effect upon The Technical Development and Production Stage of Technical Innovation in Small and Medium Industry)

  • 장태종;김능수;유영복
    • 정보관리연구
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    • 제38권4호
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    • pp.166-180
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    • 2007
  • 본 논문에서는 직무발명보상제도가 기업의 기술혁신에 얼마나 도움이 된다고 생각하느냐는 질문에 54.0%가 "많은 도움이 된다", 23%가 "기술개발에 중추적인 역할을 한다"라는 결과였다. 직무발명제도상에서 기술혁신이 발생하여 170개 기업들이 기술개발단계, 138개 기업이 아이디어 형성단계로 나타났다. 기술혁신이 기술개발단계와 아이디어 형성단계에서 집중하게 된 이유는 신제품 개발의 첫 단계인 신제품을 아이디어 창출단계에서는 가장 많은 아이디어를 창출하는데 역점을 두어야 하기 때문에 소비자, 경쟁자, 전문가 등의 다양한 원천에서 아이디어를 수집하면서 발명을 착상하게 된 것과 제품화되었을 때의 잠재적 가치가 평가기준으로 활용한다.

Isolated Boost Converter with Bidirectional Operation for Supercapacitor Applications

  • Hernandez, Juan C.;Mira, Maria C.;Sen, Gokhan;Thomsen, Ole C.;Andersen, Michael A.E.
    • Journal of Power Electronics
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    • 제13권4호
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    • pp.507-515
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    • 2013
  • This paper presents an isolated bidirectional dc/dc converter based on primary parallel isolated boost converter (PPIBC). This topology is an efficient solution in low voltage high power applications due to its ability to handle high currents in the low voltage side. In this paper, the converter has been modeled using non-ideal components and operated without any additional circuitry for startup using a digital soft-start procedure. Simulated and measured loop gains have been compared for the validity of the model. On-the-fly current direction change has been achieved with a prototype interconnecting two battery banks. A second prototype has been constructed and tested for supercapacitor operation in constant power charge mode.

Functional Surface Coating Technologies of Steel Industry

  • Choi, Chang-Hoon;Park, Sung-Ho;Kim, Jong-Sang
    • Corrosion Science and Technology
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    • 제9권6호
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    • pp.270-275
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    • 2010
  • Technical issues of steel industry change along with other industrial progresses. Traditionally, steel protection from corrosion environment was the major issue and galvanic metal coatings were mainly used to extend the lifetime of steel products. Nowadays, requirements for steel have become more diversified. More various surface and material properties are required from different field of applications. Naturally, functional surface coating has become one of the most studied areas in steel industry. For functional surface coating, various process technologies and coating products are investigated. In this article, recent trends of functional coating technologies and products are introduced with brief technical descriptions of representative coating products.

도서관조직의 기술혁신 및 행정혁신에 관한 조직상황론적 연구 (A Study on the Technical and Administrative Innovation of Library Organization in the Perspective of the Contingency Theory)

  • 홍현진
    • 한국문헌정보학회지
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    • 제25권
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    • pp.343-388
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    • 1993
  • The ability of any organization to innovate itself in a rapid change of environment means the existence of the organization. Innovative activity is achieved in different ways according to the objectives of organization. the characteristics of external environmental factors. and various attributes in organization. In the present study. all the existing approaches to the innovative nature of organization were synthetically compared to each other and evaluated: then. for a more rational approach. a research model was built and suggested by establishing the inclusive variables of the innovative nature of library organization and categorizing the types of such nature. Additionally. an empirical. analytical study on such a model was done. That is. paying regard to the fact that innovation has basically a close relation with the circumstantial factors of organization. synthetic, circumstantial relations were clarified. considering the external environmental factors and internal characteristics of organization. In the study. the innovation of library organization was seen in two parts i.e .. the feasible degree of technical innovation and the feasible degree of administrative innovation. Regarding the types of innovative implementation. according to the feasible degree of innovation, four types such as a stationary type. technic-oriented type, organization-oriented type. and technical-socio systematic type were classified. There were nine independent variables-i.e., the scale of organization. available resources of the organization, formalization, differentiation, specialization. decentralization, recognizant degree of the technical attribute. degree of response to the change of technical environment, and professional activities. There were three subordinate variables - i.e., technical innovation, administrative innovation. and the performance of organization. Through establishment of such variables, the factors which might influence the innovation of library organization were understood, and with the types of the innovative implementation of library organization being classified according to the feasible degree of innovation. the characteristics of library organization were reviewed in the light of each type. Also. the performance of library organization according to the types of the innovative implementation of library organization was analyzed. and the relations between the types of innovative implementation according to circumstantial variables and the performance of library organization were clarified. In order to clarify the adequacy of the research model in the methodology of empirical study, data were collected from 72 university libraries and 38 special libraries. and for a hypothetical test of the research model. an analysis of correlations, a stepwise regression analysis. and One Way ANOVA were utilized. The following are the major results or findings from the study 1) It appeared there is a trend that the bigger the scale of organization and available resources are, the more active the professional activity of the managerial class is, and the higher the recognizant degree of technical environment (recognizant degree of technical attributes and the degree of response t9 the change of technical environment) is, the higher the feasible degree of innovation becomes. 2) It appeared that among the variables influencing the feasible degree of technical innovation, the order from the variable influencing most was first, the recognizant degree of technical innovation: second, the available resources of organization: and third, professional activity. Regarding the variables influencing the feasible degree of administrative innovation from the most influential variable, it appeared they were the available resources of organization, the differentiation of organization. and the degree of response to the change of technical environment. 3) It appeared that the higher the educational level of the managerial class is, the more active the professional activity becomes. It seemed there is a trend that the group of library managers whose experience as a librarian was at the middle level(three years to six years of experience) was more active in research activity than the group of library managers whose experience as a librarian was at a higher level(more than ten years). Also, it appeared there is a trend that the lower the age of library managers is, the higher the recognizant degree of technical attributes becomes. and the group of library managers whose experience as a librarian was at the middle level (three years to six years of experience) recognized more affirmatively the technical aspect than the group of library managers whose experience as a librarian was at a higher level(more than 10 years). Also, it appeared that, when the activity of the professional association and research activity are active, the recognizant degree of technology becomes higher, and as a result. it influences the innovative nature of organization(the feasible degree of technical innovation and the feasible degree of administrative innovation). 4) As a result of the comparison and analysis of the characteristics of library organization according to the types of innovative implementation of library organization. it was indicated there is a trend that the larger the available resources of library organization, the higher the organic nature of organization such as differentiation. decentralization, etc., and the higher the level of the operation of system development, the more the type of the innovative implementation of library organization becomes the technical-socio systematic type which is higher both in the practical degrees of technical innovation and administrative innovation. 5) As a result of the comparison and analysis of the relations between the types of innovative implementation and the performance of organization, it appeared that the order from the highest performance of organization is the technical-socio systematic type, then the technic-oriented type, the organization­oriented type, and finally the stationary type which is lowest in such performance. That is, it demonstrated that, since the performance of library organization is highest in the library of the technical-socio systematic type while it is lowest in the library whose practical degrees in both technical innovation and administrative innovation are low, the performance of library organization differs significantly according to the types of innovative implementation of library organization. The present study has extracted the factors influencing innovation, classified systematically the types of innovative implementation, and inferred the synthetical, circumstantial correlations between the types and the performance of organization, and empirically inspected those factors. However, due to the present study's restrictive matters and the limit of the research design, results from the study should be more prudently interpreted. Also, the present study, as an investigative study of the types of innovative implementation, with few preceding studies, requires more complete hypothetical inference based on the results of the present study. In other words, if more systematical studies are given to understanding the relations, it will devote the suggestion and demonstration of a more useful theory.

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민들레 추출액을 첨가한 돈육패티의 냉장저장 중 품질변화 (Changes in Physicochemical Properties of Pork Patty with Dandelion Extract during Refrigerated Storage)

  • 최영준;박현숙;이재상;박경숙;박성숙;정인철
    • 한국식품조리과학회지
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    • 제31권4호
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    • pp.423-430
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    • 2015
  • This study was carried out to investigate the effects of dandelion leaf, root and whole part extracts on the physicochemical characteristics of pork patties stored at $4^{\circ}C$ for 10 days. Four types of pork patties were evaluated: ice-water-added (T0), dandelion leaf extract (T1), dandelion root extract (T2) and dandelion whole part extract (T3). The pH decreased significantly during storage, but increased after 10 days of storage. The pH was highest in T0 during storage. The L value of T0 increased whereas T1, T2 and T3 did not significantly changed during storage. The a value decreased with a longer storage period, and the a values for T1, T2 and T3 were higher than that of T0 during storage. The b value did not change significantly during storage. The TBARS increased with a longer storage period, and the values for T0, T1, T2 and T3 were 0.87, 0.29, 0.47 and 0.31 mg MA/kg, respectively, after 10 days of storage. The VBN content value of T0 increased, but those of T1, T2 and T3 did not significantly change during storage. The water holding capacity of T0 decreased, but those of T1, T2 and T3 did not significantly change during storage. Cooking loss increased during storage and that of T0 was higher than those of T1, T2 and T3. Hardness and chewiness decreased while springiness and cohesiveness increased during storage.

Useful and Effective Diagnosis and Evaluation Tools for Eenvironmental Change in Increased Mill Water System Closure

  • Linda R. Robertson;Lee, Byung-Tae;Kim, Tae-Joon
    • 펄프종이기술
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    • 제33권5호
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    • pp.1-11
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    • 2001
  • In the past, abundant and clean water was available for paper mills'use. However, the growth of population and industry made water less available nowadays. Also, environmental regulation limits wastewater discharge, which affects mill operation cost. Therefore, paper mills are under pressure to use more recycled water and mill system closure. As a result, chemical and physical parameters of water are changing and new environment if being created for microorganisms in paper mill system as well. The more soluble or suspended organic materials are increased as more water is recycled and less or scarce dissolved oxygen is available, depending on the degree of recycled water usage. Microorganism flora ill paper mill system will be a1so shifted according to the environmental change of mill system. Anaerobic bacteria, including sulfate reducing bacteria (SRB), will be dominant in the system as very low or almost no oxygen available in the system. Nevertheless, it is common in domestic paper mills that employ the same and old biocides as a means of microbial control, and microbiological control is often less recognized or even neglected. The right biocide selection for increased reductive environment of mills is critical for operation and estimated loss from paper quality defects such as sheet break, holes due to microbiological cause is tremendous compared to the microbiological control cost. It is imperative to investigate and diagnosis the environmental change of mills for right control of cumbersome microorganisms. Several useful diagnosis tools, including new technology employing OFM(Optical Fouling Monitor) in situ, are illustrated.

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