• 제목/요약/키워드: Engineering Practice

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Capacity Reservation for Due Date Promising : A Conceptual Framework

  • Seung J. Noh;Suk-Chul Rim
    • 산업경영시스템학회지
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    • 제24권64호
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    • pp.53-62
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    • 2001
  • In make-to-order manufacturing, if orders are processed and promise first-served base, then the urgent orders from important customers in .practice, orders are not confirmed upon receipt; and delayed as uncertainty of due date causes significant waste of cost and time. propose a new concept of reserved capacity as an alternative to accommodate the urgent orders from important customers, while the due dale of all of orders arrival; and suggest a flew operational policies.

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FUZZY CONTROLLER WITH MATRIX REPRESENTATION OPTIMIZED BY NEURAL NETWORKS

  • Nakatsuyama, Mikio;Kaminaga, Hiroaki;Song, Bei-Dong
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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    • pp.1133-1136
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    • 1993
  • Fuzzy algorithm is essentially nondeterministic, but to guarantee the stable control the fuzzy control program should be deterministic in practice. Fuzzy controllers with matrix representation is very simple in construction and very fast in computation. The value of the matrix is not adequate at the first place, but can be modified by using the neural networks. We apply the simple heuristic techniques to modify the matrix successfully.

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강구조 시스템의 에너지 흡수효율 (Energy Absorption Efficiency of Structural Steel System)

  • 김장훈
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2003년도 춘계 학술발표회논문집
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    • pp.294-301
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    • 2003
  • The energy concept has been applied to the reported experimental results of six different structural steel connections to investigate the characteristics of system-dependent energy curve and energy absorption efficiency. For this the concept o( static and kinematic energy absorption efficiency has been defined. The present paper closes with the implication of the necessity of further investigation to extend the energy concept to reach the engineering practice.

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Effects of Induction Heat Bending Process on Microstructure and Corrosion Properties of ASME SA312 Gr.TP304 Stainless Steel Pipes

  • Kim, Nam In;Kim, Young Sik;Kim, Kyung Soo;Chang, Hyun Young;Park, Heung Bae;Sung, Gi Ho
    • Corrosion Science and Technology
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    • 제14권3호
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    • pp.120-126
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    • 2015
  • The usage of bending products recently have increased since many industries such as automobile, aerospace, shipbuilding, and chemical plants need the application of pipings. Bending process is one of the inevitable steps to fabricate the facilities. Induction heat bending is composed of compressive bending process by local heating and cooling. This work focused on the effect of induction heat bending process on the properties of ASME SA312 Gr. TP304 stainless steel pipes. Tests were performed for base metal and bended area including extrados, intrados, crown up, and down parts. Microstructure was analyzed using an optical microscope and SEM. In order to determine intergranular corrosion resistance, Double Loop Electrochemical Potentiokinetic Reactivation (DL-EPR) test and ASTM A262 practice A and C tests were done. Every specimen revealed non-metallic inclusion free under the criteria of 1.5i of the standard and the induction heat bending process did not affect the non-metallic inclusion in the alloys. Also, all the bended specimens had finer grain size than ASTM grain size number 5 corresponding to the grain sizes of the base metal and thus the grain size of the pipe bended by induction heat bending process is acceptable. Hardness of transition start, bend, and transition end areas of ASME SA312 TP304 stainless steel was a little higher than that of base metal. Intergranular corrosion behavior was determined by ASTM A262 practice A and C and DL-EPR test, and respectively step structure, corrosion rate under 0.3 mm/y, and Degree of Sensitization (DOS) of 0.001~0.075% were obtained. That is, the induction heat bending process didn't affect the intergranular corrosion behavior of ASME SA312 TP304 stainless steel.

The Removal Efficacy of Heavy Metals and Total Petroleum Hydrocarbons from Contaminated Soils by Integrated Bio-phytoremediation

  • Lai, Wen-Liang;Lee, Fang-Yin;Chen, Colin S.;Hseu, Zeng-Yei;Kuo, Yau-Lun
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제19권5호
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    • pp.35-44
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    • 2014
  • In this study, the bio-phytoremediation and phytoremediation technologies were applied to the soils contaminated with total petroleum hydrocarbons (TPH) and heavy metals to evaluate the remediation efficacy from May 2012 to December 2013. Poplar (Populus bonatii Levl.) and Sun Hemp (Crotalaria juncea L.) were selected and planted in phytoremediation practice. These plants were also utilized in the bio-phytoremediation practice, with the addition of earthworm (Eisenia fetida) and petroleum-degrading bacteria (Pseudomonos sp. NKNU01). Furthermore, physiological characteristics, such as photosynthesis rate and maximal photochemical yield, of all testing plants were also measured in order to assess their health conditions and tolerance levels in adverse environment. After 20 months of remedial practice, the results showed that bio-phytoremediation practice had a higher rate of TPH removal efficacy at 30-60 cm depth soil than that of phytoremediation. However, inconsistent results were discovered while analyzing the soil at 100 cm depth. The study also showed that the removal efficiency of heavy metals was lower than that of TPH after remediation treatment. The results from test field tissue sample analysis revealed that more Zinc than Chromium was absorbed and accumulated by the tested plants. Plant height measurements of Poplar and Sun Hemp showed that there were insignificant differences of growth between the plants in remediation plots and those in the control plot. Physiological data of Poplar also suggested it has higher tolerance level toward the contaminated soils. These results indicated that the two testing plants were healthy and suitable for this remediation study.

보건관리전문기관의 작업환경관리 지도에 따른 일부 지역 사업장 보건업무담당자와 근로자의 실천도 (Practice of Health Managers and Workers according to Guidance of Work Environment Management of Specialized Health Management Institution)

  • 김윤희
    • 한국산업보건학회지
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    • 제26권2호
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    • pp.198-209
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    • 2016
  • Objectives: This study aimed to provide basic data for the improvement of the guidance services for the management of the workplace environment of the specialized health management institution, by making inquiries on the perception and extent of practice by health managers and workers in the workplace. Methods: Workplaces with officially noted environmental hazards of noise, organic compounds and/or dust-metals were selected in a South Korean metropolitan city in 2015. The workplace health managers(hereinafter referred to as 'manager') and workers at 97 workplace were interviewed. Managers are those who are in charge of health management at the corresponding workplace and the workers were subjected to in-depth interviews by sampling one worker for each of the workplace. Results: The majority of the managers acknowledged the guidance services of the specialized health management institution affirmatively. Regarding the extent of practice in accordance with the guidance on engineering improvement, only 23 managers(37.1%) responded. With respect to education, 40 managers(41.2%) responded that it was implemented along with 35 workers(36.1%) who responded that they received education, showing no significant difference between manager and worker. Regarding the actual wearing of the protective equipment, however, 83 of the manager(85.6%) insisted that workers wore the protective devices while only 44 workers(49.5%) responded that they actually wore the devices, thereby illustrating a significant difference between managers and workers. Conclusions: These results suggest the urgent necessity of improvement in the mechanism of guidance services of the specialized health management institution for the workplace environment management.

병원 의사결정지원시스템의 서비스 품질이 경영성과에 미치는 영향 : K대병원 사례 중심으로 (A Study on the Effects of the Service Quality of Hospital's Decision Support System on Management Performance : the Case of K-University Hospital)

  • 박진희;권두순;이미영
    • Journal of Information Technology Applications and Management
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    • 제21권2호
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    • pp.81-98
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    • 2014
  • Recently, due to external environment like the changes in health policy and various healthcare accreditations, along with hospital's internal efforts to improve the quality of medical services, demands for the development of medical information systems are increasing. Some examples are clinical information like DUR (Drug Utilization Review), CVR (Critical Value Report), and automatic benefit processing by treatment purposes, or hospital DSS (Decision Support System) on overall medical practice. Such systems act as a guide in making clinic judgments during practice or in other medical practice, and their effects on the medical treatment improvements are being proven by previous studies. In the reality of increasing attention in the effects of medical treatment improvement, studies related to hospital DDS were mostly focused on clinical, technical, and engineering points of view, and studies focusing on the user viewpoint are very limited. In order to verify the effects of DSS on practice improvements and hospital's management performance, this study used a research model constructed to verify how SERVQUAL of hospital DSS affects hospital management performance in BSC (Balanced Score Card) point of view. To empirically verify the research model, a questionnaire was conducted on the basis of "K-University Hospital's DSS" on clinicians and hospital employees related to system development, and the relationships between the factors were analyzed through path analysis. As a result of path analysis, excluding reactivity, tangibility, confidence, reliability, empathy among service qualities, had partially significant effects on management performance factors (learning and growth, internal process, financial affairs). This study is to prepare the theoretical ground on the management performance analysis of hospital DSS, and suggest the service quality of the system that should be considered in the planning and development stages for improved system.

Using Practice Context Models to Knowledge Management in Proof-of-Concept Activities: A Contribution of Knowledge Networks and Percolation Theory

  • Neto, Antonio Jose Rodrigues;Borges, Maria Manuel;Roque, Licinio
    • Journal of Information Science Theory and Practice
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    • 제9권1호
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    • pp.1-23
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    • 2021
  • This study introduces novel research using Practice Context Models supported by Knowledge Networks and Percolation Theory with the aim to contribute to knowledge management in Proof-of-Concept (PoC) activities. The authors envision this proposal as a potential instrument to identify network structures based on a percolation (propagation) threshold and to analyze the importance of nodes (e.g., practitioners, practices, competencies, movements, and scenarios) during the percolation of knowledge in PoC activities. After thirty months immersed in the natural PoC habitat, acting as observers and practitioners, and supported by an ethnographic exercise and a designer-research mindset, the authors identified the production of meaning in PoC activities occurring in a hermeneutic circle characterized by the presence of several knowledge networks; thus, discovering the 'natural knowledge' in PoC as a spectrum of cognitive development spread throughout its network, as each node could produce and disseminate certain knowledge that flows and influences other nodes. Therefore, this research presents the use of Practice Context Models 'connected' to Knowledge Networks and Percolation Theory as a potential and feasible proposal to be built using the attribution of values (weights) to the nodes (e.g., practitioners, practices, competencies, movements, scenarios, and also knowledge) in the context of PoC with the aim to allow the players (e.g., PoC practitioners) to have more flexibility in building alliances with other players (new nodes); that is, focusing on those nodes with higher value (focus on quality) in collaboration networks, i.e., alliances (connections) with the aim to contribute to knowledge management in the context of PoC.

도플러효과를 이용한 오케스트라 지휘 연습 툴 연구 (Study on Orchestra Conducting Practice Tool using Doppler Effect)

  • 임양규;박진완
    • 한국과학예술포럼
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    • 제30권
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    • pp.367-376
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    • 2017
  • 본 연구는 지휘전공자와 지휘자가 언제, 어디서나 지휘 연습을 할 수 있는 지휘 연습 프로그램을 만든 것을 목표로 한다. 그동안 다양한 종류의 관련 연구들이 있었지만, 대부분 지휘 전공자를 위해 최적화 되어 있지 않았다. 게다가 장소와 공간에 제약을 받지 않는 지휘 연습을 위해서는 악기 연주자들처럼 휴대가 가능한 수준의 도구가 되어야 한다. 특히 오케스트라 지휘자가 지휘 박자 젓기만을 하는 메트로놈과 같은 사람이 아니라 연주자와 소통하면서 큐잉(Cueing)을 통해 악단을 진두지휘해 나간다는 대중에겐 잘 알려져 있지는 않지만 연습이 필요한 부분에 대해 좀 더 보강을 하고자 노력하였다. 본 연구에서 제시한 연습 툴은 기존에 시행된 관련 연구들의 한계를 극복하기 위해 도플러 효과를 사용한다. 호환성이 좋고, 간편하며, 정확도가 높은 도플러 방식은 기존에 존재하는 센서들을 활용한 동작감지 방법보다 우수하다는 결론을 얻었다. 향후 추가 연구를 통해 좀 더 발전하게 되면 지휘 뿐 아니라 다양한 매체의 인터랙션 도구로 쓰일 것으로 예상된다.

I형 프리스트레스트 콘크리트 거더교의 활하중 분배 (Live Load Distribution in Prestressed Concrete I-Girder Bridges)

  • 김광양;강대희;이환우
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2008년도 정기 학술대회
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    • pp.288-293
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    • 2008
  • The standard prestressed concrete I-girder bridge (PSC I-girder bridge) is one of the most prevalent types for small and medium bridges in Korea. When determining the member forces in a section to assess the safety of girder in this type of bridge, the general practice is to use the simplified practical equations or the live load distribution factors proposed in design standards rather than the precise analysis through the finite element method or so. Meanwhile, the live load distribution factors currently used in Korean design practice are just a reflection of overseas research results or design standards without alterations. Therefore, it is necessary to develop an equation of the live load distribution factors fit for the design conditions of Korea, considering the standardized section of standard PSC I-girder bridges and the design strength of concrete. In this study, to develop an equation of the live load distribution factors, a parametric analysis and sensitivity analysis were carried out on the parameters such as width of bridge, span length, girder spacing, width of traffic lane, etc. Then, an equation of live load distribution factors was developed through the multiple linear regression analysis on the results of parametric analysis. When the actual practice engineers design a bridge with the equation of live load distribution factors developed here, they will determine the design of member forces ensuring the appropriate safety rate more easily. Moreover, in the preliminary design, this model is expected to save much time for the repetitive design to improve the structural efficiency of PSC I-girder bridges.

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