• 제목/요약/키워드: Unit Process

검색결과 3,659건 처리시간 0.043초

AE 감시 장치를 이용한 센터리스 연삭 공적의 감시 (Process Monitoring of Centerless Grinding Using an AE Monitoring Unit)

  • 김성렬;김화영;김선호;안중환
    • 한국정밀공학회지
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    • 제16권1호통권94호
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    • pp.108-115
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    • 1999
  • Since grinding is a more complicated process than any other machining process, it is hard for operators to setup a grinding machine properly and to find out correctly abnormal grinding states resulting in damages to products. Abnormalities would be caused by improper setup, improper dressing/grinding conditions which are likely to be occurred without skilled operators' attention. In this study, an AE monitoring unit is developed to help operators conduct with ease setup, and set properly dressing/grinding conditions. AErms(root-mean-square) signal being monitored, on-going process states during grinding and dressing is visualized for machine operators to judge whether the processes are in good condition. Evaluation tests are carried out on centerless grinding machines-both cylindrical and internal. The developed AE monitoring system is verified to be useful to check grinding/dressing states in process even in the centerless grinding of which process is most unknown among various grinding methods because of the complex structure.

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Roll out 알고리듬을 이용한 반복 작업을 하는 안전병렬기계 알고리듬 개발 (- Development of an Algorithm for a Re-entrant Safety Parallel Machine Problem Using Roll out Algorithm -)

  • 백종관;김형준
    • 대한안전경영과학회지
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    • 제6권4호
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    • pp.155-170
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    • 2004
  • Among the semiconductor If-chips, unlike memory chips, a majority of Application Specific IC(ASIC) products are produced by customer orders, and meeting the customer specified due date is a critical issue for the case. However, to the one who understands the nature of semiconductor manufacturing, it does not take much effort to realize the difficulty of meeting the given specific production due dates. Due to its multi-layered feature of products, to be completed, a semiconductor product(called device) enters into the fabrication manufacturing process(FAB) repeatedly as many times as the number of the product specified layers, and fabrication processes of individual layers are composed with similar but not identical unit processes. The unit process called photo-lithography is the only process where every layer must pass through. This re-entrant feature of FAB makes predicting and planning of due date of an ordered batch of devices difficult. Parallel machines problem in the photo process, which is bottleneck process, is solved with restricted roll out algorithm. Roll out algorithm is a method of solving the problem by embedding it within a dynamic programming framework. Restricted roll out algorithm Is roll out algorithm that restricted alternative states to decrease the solving time and improve the result. Results of simulation test in condition as same as real FAB facilities show the effectiveness of the developed algorithm.

이중 스테이지를 이용한 대면적 3차원 광/유체 마이크로 디바이스 제작에 관한 연구 (Fabrication of Three-Dimensional Micro Optical and Fluidic System Using Dual Stage Nanostereolithography Process)

  • 임태우;양동열
    • 설비공학논문집
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    • 제27권10호
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    • pp.552-557
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    • 2015
  • The nanostereolithography process using a femtosecond laser has been shown to have strong merits for the direct fabrication of 2D/3D micro structures. In addition, a femtosecond laser provides efficient tools for precise micromachining owing to the advantages of a small and feeble heat effect zone. In this paper, we report an effective fabrication process of 3D micro optical and fluidic devices using nanostereolithography process composed of a dual stage system. Process conditions for additive and subtractive fabrication are examined. The Piezo stage scanning system is used for 3D micro-fabrication in unit area of sub-mm scale, and the motor stage is employed in fabrication on the scale of several mm. The misalignment between the pizeo- and motor- stages is revised through rotational transformation of CAD data in the unit domain. Here, the effectiveness of the proposed process is demonstrated through examples using 3D optical and microfluidic structures.

Business Process Evaluation and Case Study for Sequential Application of BPM

  • Song, Young-Woong;Lim, Hyung-Chul;Choi, Yoon-Ki
    • Journal of Construction Engineering and Project Management
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    • 제2권2호
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    • pp.36-44
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    • 2012
  • Adoption and practical application of BPM yet remains at a theoretic and methodological level for many industrial sectors. As for construction industry, adapting BPM into enterprise resource across all business processes could cause problems due to rapid change in corporate operation systems. Furthermore, it is unable to predict potential risks of business process while BPM are being applied. Therefore, applying BPM model to core strategy and individual task seems more effective than applying BPM model to the entire enterprise resource planning. In this paper, we define BPM and suggest a BPM model by analyzing each business unit in order to evaluate each business unit which is included in the business process architecture based on quantitative standards. This paper also presents a sequential application plan for business process model. Finally, a case study is demonstrated for the application of BPM system, focusing on cost management business, which turned out to be a top priority in the aspect of efficiency and ease based on priority analysis.

조직문화가 의료사회사업서비스의 질에 미치는 영향에 관한 연구 (A study on the quality of medical social work influenced by organizational culture of hospital)

  • 강흥구
    • 보건행정학회지
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    • 제12권4호
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    • pp.34-55
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    • 2002
  • In this study, the impact of organizational culture on the quality of social work services in hospitals were empirically analysed. A mailed questionnaire survey was conducted between February 19 and April 10, 2001. A sample of total 70 hospitals, including general hospitals with one social worker at least and single-department hospital with two social workers or more, were identified nationwide through the registry of Korean Association of Medical Social Workers and Korean Association of Hospitals. According to coping strategy and reacting pattern with the environmental changes, four types of organizational culture in each hospital, classified as group culture, developmental culture, hierarchial culture, and rational culture, were adopted for the independent variables. Three dimensional aspects of quality of social work service - structure, process, and outcome were selected as dependent variables in this study. Also the quality of social work service was distributed into provider-perceiving quality and consumer-perceiving quality The major findings were as following in summary; First, most social workers reported that the characteristic of culture in their hospitals are group culture the first, hierarchial culture the second, developmental culture the third, and rational culture finally in order of comparing the level of quality perceived between social worker's recognition. Second, service provider and consumer, The provider-perceiving quality showed less score than that of consumer, especially the lowest was the score of quality of outcome perceived by provider. Third, according to the types of organizational culture, there were significantly different levels of quality in total social work services, structure dimension and process dimension. The quality of outcome dimension did not show significant differences among the type of organizational culture. Finally, the most influential variables to the quality of social work service ice proved departmental form of social work unit, leader of social work unit, and developmental culture of hospital To assure quality services, accordingly, social work unit in hospital is required to be organized as a single unit, that means to be an independent department of which qualified social worker is supposed to control the unit. It is strongly recommended to develop leadership for the leaders of social work unit.

Sepsis induces variation of intestinal barrier function in different phase through nuclear factor kappa B signaling

  • Cao, Ying-Ya;Wang, Zhong-Han;Xu, Qian-Cheng;Chen, Qun;Wang, Zhen;Lu, Wei-Hua
    • The Korean Journal of Physiology and Pharmacology
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    • 제25권4호
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    • pp.375-383
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    • 2021
  • The intestinal barrier function disrupted in sepsis, while little is known about the variation in different phases of sepsis. In this study, mouse models of sepsis were established by caecal ligation and puncture (CLP). The H&E staining of sections and serum diamine oxidase concentration were evaluated at different timepoint after CLP. TUNEL assay and EdU staining were performed to evaluate the apoptosis and proliferation of intestinal epithelium. Relative protein expression was assessed by Western blotting and serum concentrations of pro-inflammatory cytokines was measured by ELISA. The disruption of intestinal barrier worsened in the first 24 h after the onset of sepsis and gradually recovered over the next 24 h. The percentage of apoptotic cell increased in the first 24 h and dropped at 48 h, accompanied with the proliferative rate of intestinal epithelium inhibited in the first 6 h and regained in the later period. Furthermore, the activity of nuclear factor kappa B (NF-κB) presented similar trend with the intestinal barrier function, shared positive correction with apoptosis of intestinal epithelium. These findings reveal the conversion process of intestinal barrier function in sepsis and this process is closely correlated with the activity of NF-κB signaling.

Participation and Influencing Factors in the Decision-Making of Life-Sustaining Treatment: A Focus on Deceased Patients with Hematologic Neoplasms

  • Jae Eun Jang;Jeong Moon Ryu;Min Hee Heo;Do Eun Kwon;Ji Yeon Seo;Dong Yeon Kim
    • Journal of Hospice and Palliative Care
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    • 제26권2호
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    • pp.69-79
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    • 2023
  • Purpose: This study aimed to investigate the involvement of patients who died from hematologic neoplasms in the decision-making process surrounding the withdrawal of life-sustaining treatment (LST). Methods: A total of 255 patients diagnosed with hematologic neoplasms who ultimately died following decisions related to LST during their end-of-life period at a university hospital were included in the study. Data were retrospectively obtained from electronic medical records and analyzed utilizing the chi-square test, independent t-test, and logistic regression. Results: In total, 42.0% of patients participated in the decision-making process regarding LST for their hematologic neoplasms, while 58.0% of decisions were made with family involvement. Among these patients, 65.1% died in general wards and 34.9% in intensive care units (ICUs) as a result of decisions such as the suspension of LST. The period from the LST decision to death was longer when the decision was made by the patient (average, 27.15 days) than when it was made by the family (average, 7.48 days). Most decisions were made by doctors and family members in the ICU, where only 20.6% of patients exercised their right to make decisions regarding LST, a rate considerably lower than 79.4% observed in general wards. Decisions to withhold or withdraw LST were more commonly made by patients themselves than by their families. Conclusion: The key to discussing the decision to suspend hospice care and LST is respecting the patient's self-determination. If a patient is lucid prior to admission to the ICU, considerations about suspending LST should involve the patient input.

시뮬레이션을 이용한 다층 P.C.B. 생산공정의 운영분석 (Analysisi of Multi-Layer P.C.B. Manufacturing Process by Simulation)

  • 김만식
    • 한국시뮬레이션학회논문지
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    • 제1권1호
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    • pp.17-24
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    • 1992
  • The capacity of the drilling process in Multi-Layer PCB fabrication can be affected by various process parameters determining material flows in the unit operations. The ratio of mass-lamination to pin lamination and the number of stacks as the most critical paramaters, among them, were chosen on the basis of exhaustive field evaluation to study their effects on the capacity of the process. The best alternative condition for maximum capacity of the process was selected by simulation of process.

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무산소-산소 공정에서 생물학적 질소 제거 모델의 검증 (Verification of biological nitrogen removal model in anoxic-oxic process)

  • 이병대;정경훈
    • 한국환경과학회지
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    • 제14권12호
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    • pp.1155-1161
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    • 2005
  • Anoxic-oxic process were analyzed numerically for the each unit and final TN effluent by Water Quality Management(WQM) model and the results were compared data from these sewage or wastewater treatment plants. No bugs and logic error were occurred during simulation work. All of the simulation results tried to two times were obtained and both results were almost same thus this model has good reappearance. A few of simulation results were deviated with measured data because lack of influent water qualities are reported however simulation results have wholly good relationship with measured data. Also each unit of simulation result was kept good relationship with that of measured data therefore this WQM model has good reliance. Finally, WQM model predicts final TN effluent within ${\pm}4.1\;mg/{\ell}$

TFT-LCD BLU용 고압 케이블의 재료특성 및 제조공정 개선을 통한 성능 향상 (Evaluation in Performance of High Voltage Cable for BLU of TFT-LCD by Improvement for Material and Manufactured Process)

  • 정진도;김재훈;구경완;황승민
    • 전기학회논문지P
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    • 제58권4호
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    • pp.495-498
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    • 2009
  • To improve the efficiency of the high voltage cable for BLU(backlight unit) of TFT-LCD(Thin Film Transistor-Liquid Crystal Display), the analysis for the trial products(UL3239, UL3633) is conducted by using SEM(scanning electron microscope) and EDX(Energy Dispersive X-ray Spectroscopy). The result that it is possible to accumulate the know-how to about stranding pitch through effective improvement of stranding process. The troubles which are the badness of withstanding voltage and tensile strength etc. are solved by development of excellent material. Furthermore, phenomenon of conductor unfasten in the harness work is solved by improvement of the stranding wire process.