• Title/Summary/Keyword: Limits Cycle

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A Study of the PDCA and CAPD Economic Designs of the $\bar{x}$ Control Chart

  • Sun, Jing;Tsubaki, Michiko;Matsui, Masayuki
    • Industrial Engineering and Management Systems
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    • v.6 no.1
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    • pp.11-21
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    • 2007
  • The PDCA (Plan, Do, Check and Act) cycle is often used in the field of quality management. Recently, business environments have become more competitive, and the due time of products has shortened. In a short production run process, to increase efficiency of management, the necessity for distinguishing the PDCA design that starts with PLAN and the CAPD design that starts with CHECK has been clarified. Starting from Duncan (1956), there have been a number of papers dealing with the economic design of control charts from the viewpoint of production run. Some authors (Gibra, 1971; Ladany and Bedi, 1976; etc.) have studied the economic design for finite-length runs; other authors (Crowder, 1992; Del Castillo and Montgomery, 1996; etc.) have studied the economic design for short runs. However, neither the PDCA nor the CAPD design of control charts has been considered. In this paper, both the PDCA and CAPD designs of the $\bar{\x}$ chart are defined based on Del Castillo and Montgomery's design (1996), and their mathematical formulations are shown. Then from an economic viewpoint, the optimal values of the sample size per each sampling, control limits width, and the sampling interval of the two designs are studied. Finally, by numerically analyzing the relations between the key parameters and the total expected cost per unit time, the comparisons between the two designs are considered in detail.

The problems of spatial modernization of the economy and new approaches to way out from crisis: Kazakhstan's experience

  • Kireyeva, Anel A.;Nurlanova, Nailya K.
    • Journal of Distribution Science
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    • v.11 no.3
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    • pp.39-48
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    • 2013
  • Purpose - This study aims to analyze the main problems of spatial modernization of the economy, and to develop new approaches to way out from crisis, to accelerate of innovations process from the cities-centers to the underdeveloped regions. Research design, data, methodology - The application of scientific methods in this research will allow to systematize the available data, from both a theoretical and empirical perspective. The study employs the method of ranking regions, the rate of innovation activity and comparative evaluation of R&D indicator. In addition, the authors proposed the method of modeling of innovation diffusion in the regions. Results - This study confirms that the need help for the underdeveloped regions, but we should clearly understand the limits of opportunities and to choose the right mechanisms. Further, this study shows it's important to maintain the regions with high innovation activity, as they are growth poles, which are play the role of translator's innovations to the periphery. Conclusions - According to the results of this theoretical and empirical study proved that modernization of the economy is realized faster in the regions with the best conditions for the diffusion of innovations, the higher the concentration of the population, a more developed infrastructure and reduced of administrative barriers.

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In Vivo Evaluation of Curcumin-loaded Nanoparticles in a A549 Xenograft Mice Model

  • Yin, Hai-Tao;Zhang, De-Geng;Wu, Xiao-Li;Huang, Xin-En;Chen, Gang
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.1
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    • pp.409-412
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    • 2013
  • Curcumin (Cum) has been reported to have potential chemo-preventive and chemotherapeutic activity through influencing various processes, inducing cell cycle arrest, differentiation and apoptosis in a series of cancers. However, the poor solubility of Cum limits its further applications in the treatment of cancer. We have previously reported Cum-loaded nanoparticles (Cum-NPs) prepared with amphilic methoxy poly(ethylene glycol)-polycaprolactone (mPEG-PCL) block copolymers. The current study demonstrated superior antitumor efficacy of Cum-NPs over free Cum in the treatment of lung cancer. In vivo evaluation further demonstrated superior anticancer effects of Cum-NPs by delaying tumor growth compared to free Cum in an established A549 transplanted mice model. Moreover, Cum-NPs showed little toxicity to normal tissues including bone marrow, liver and kidney at a therapeutic dose. These results suggest that Cum-NPs are effective to inhibit the growth of human lung cancer with little toxicity to normal tissues, and could provide a clinically useful therapeutic regimen. They thus merit more research to evaluate the feasibility of clinical application.

Significance of Dissolved Nucleic Acids in Dissolved Organic Phosphorus (DOP) Pool and Their Dynamics in oceanic Phosphorus Cycle (용존 유기인 종 용존 핸산의 중요성 및 대양 인 순환에서의 의미)

  • CHO, BYUNG C.
    • 한국해양학회지
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    • v.25 no.3
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    • pp.145-150
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    • 1990
  • An analysis of collected data on components of dissolved organic phosphorus (DOP) and DOP is made to search for important components of DOP pool and their implications in phosphorus (P) cycling. The significance of dissolved nucleic acids (D-NA) apparently tends to increase with increasing trophic status of oceanic waters. Interestingly the sum of all 5-nucleotide and D-NA seems to dominate the DOP pool. Thus, materialization of D-NA could be a significant pathway of P cycling in surface oceanic waters and it might be of great importance in lakes where P limits primary production. Processes related to death of Microbes are responsible for D-NA and DOP production in surface waters, and incomplete digestion of preys by grazers seems to be an important mechanism in D-NA production.

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Design and Simulation Technologies of Flat Transformer with High Power Current (대전류 출력형 Flat Transformer 설계 및 해석 기술)

  • Han, Se-Won;Cho, Han-Goo;Woo, Bung-Chul
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.05c
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    • pp.15-17
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    • 2002
  • Leakage inductance and temperature rise are two of the more impotent problems facing the magnetic core technology of today's high frequency transformers. Excessive leakage inductance increases the stress on the switching transistors and limits the duty-cycle, and excessive temperature rise can lead the design limitation of high frequency transformer with high current. The flat transformer technology provides a very good solution to the problems of leakage inductance and thermal management for high frequency power. The critical magnetic components and windings are optimized and packaged within a completely assembled module. The turns ratio in a flat transformer is determined as the product of the number of elements or modules times the number of primary turns. The leakage inductance increase proportionately to the number of elements, but since it is reduced as the square of the turns, the net reduction can be very significant. The flat transformer modules use cores which have no gap. This eliminates fringing fluxes and stray flux outside of the core. The secondary windings are formed of flat metal and are bonded to the inside surface of the core. The secondary winding thus surrounds the primary winding, so nearly all of the flux is captured.

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Radiation Dose Assessment of ACP Hotcell for Spent Fuel Treatment in Normal Operation & Accident Case (사용후핵연료 처리를 위한 ACP 핫셀의 정상운영 및 사고시 방사선 환경영향평가)

  • 국동학;정원명;구정회;조일제;이은표;유길성
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.2 no.3
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    • pp.155-164
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    • 2004
  • Advanced spent fuel Conditioning Process(ACP) project which is under development for efficient spent fuel management has finished process feasibility study and is preparing $\alpha$-${\gamma}$ type hot cell construction for process experimentation. Radiation dose evaluation for the radioactive nuclides were preliminarily performed for normal operation and accident case with the basic concept design report, the meteorological data and the recent site specific data. According to the production and release rate of nuclides, dose evaluations for residents around facility were performed. The evaluation result shows a safe margin for regulation limits and SAR(Safety Analysis Report) limit of IMEF(Irradiated Material Examination Facility) where this facility will be constructed.

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An Evaluation of Fatigue Properties on Dissimilar Friction Weld of Heat-Resisting Steels Used in Vehicle Valves (차량 밸브용 내열강재 이종 마찰용접부의 피로특성 평가)

  • 이동길;이상열;정재강
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.2
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    • pp.186-192
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    • 2002
  • The fatigue crack propagation characteristics were investigated on dissimilar friction weld of two kind of heat-resisting steels (STR3 and STR35) commonly used in valve materials for vehicles. A small circular artificial defect was machined to induce fatigue crack at bonded line, heat affected zone and base metal of the weld on the surface of the specimens. From the results of the experiment, the fatigue limits of the materials STR3 and STR35 were obtained to be 429.0MPa and 409.4MPa respectably. The STR35 base metal and 1.0mm HAZ specimens showed 190% and 82% higher fatigue life than STR3 base metal. And the fatigue life of 1.0mm HAZ specimen was shown 99% on STR3 and 29% on STR35 higher than that of their base metal. But the fatigue life of weld interface specimen was shown 18% on STR3 and 72% on STR35 lower than that of their base metal because of the weld interface separation.

A Mathematical Model to Evaluate the Radiological Risks for the Reuse of Decommissioning Site (원자력시설 해체부지의 재이용을 위한 방사선학적 리스크 평가모델)

  • Cheong, Jae-Hak
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.4 no.4
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    • pp.353-363
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    • 2006
  • In order to evaluate the potential radiological risks for the reuse of the site after decommissioning of nuclear facilities, a mathematical model was developed and materialized into the Microsoft $Excel{\circledR}$ spreadsheets frame. A set of input parameter values was proposed, which is useful in the preliminary risk screening step before the detailed evaluation with the site-specific data. It appeared that the screening levels calculated by the present model was agreed with the derived concentration guideline limits resulted from RESRAD Ver.6.2 and the German dose criteria for releasing a nuclear site from regulatory control.

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Investigation of Cooling Effect of Flow Velocity and Cooler Location in Thermal Nanoimprint Lithography

  • Lee, Woo-Young;Lee, Ki Yeon;Kim, Kug Weon
    • Journal of the Semiconductor & Display Technology
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    • v.11 no.4
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    • pp.37-42
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    • 2012
  • Nanoimprint lithography (NIL) has attracted broad interest as a low cost method to define nanometer scale patterns in recent years. A major disadvantage of thermal NIL is the thermal cycle, that is, heating over glass transition temperature and then cooling below it, which requires a significant amount of processing time and limits the throughput. One of the methods to overcome this disadvantage is to improve the cooling performance in NIL process. In this paper, the performance of the cooling system of thermal NIL is numerically investigated by SolidWorks Flow Simulation program. The calculated temperatures of nanoimprint device were verified by the measurements. By using the analysis model, the effects of the change of flow velocity and cooler location on the cooling performance are investigated. For the 6 cases (0.1 m/s, 0.5 m/s, 1 m/s, 3 m/s, 5 m/s, 10 m/s) of flow velocity and for the 6 cases of distances (50 mm, 40 mm, 30 mm, 20 mm, 10 mm, 1 mm) of cooler location, the heat conjugated flow analyses are performed and discussed.

Predictive aeration control based on the respirometric method in a sequencing batch reactor (연속회분식반응조에서 호흡률에 기반한 포기공정의 예측제어)

  • Kim, Donghan
    • Journal of Korean Society of Water and Wastewater
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    • v.33 no.6
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    • pp.481-489
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    • 2019
  • As aeration is an energy-intensive process, its control has become more important to save energy and to meet strict effluent limits. In this study, predictive aeration control based on the respirometric method has been applied to the sequencing batch reactor (SBR) process. The variation of the respiration rate by nitrification was great and obvious, so it could be a very useful parameter for the predictive aeration control. The maximum respiration rate due to nitrification was about 60 mg O2/L·h and the maximum specific nitrification rate was about 7.5 mg N/g MLVSS·h. The aeration time of the following cycle of the SBR was daily adjusted in proportion to that which was previously determined based on the sudden decrease of respiration rate at the end of nitrification in the respirometer. The aeration time required for nitrification could be effectively predicted and it was closely related to influent nitrogen loadings. By the predictive aeration control the aerobic period of the SBR has been optimized, and energy saving and enhanced nitrogen removal could be obtained.