• 제목/요약/키워드: Part Release

검색결과 355건 처리시간 0.022초

FMS에서 공구 일정계획을 고려한 부품투입 방법 (A Part Release Method Considering Tool Scheduling in FMS)

  • 이충수;최정상
    • 한국경영과학회지
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    • 제28권1호
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    • pp.1-10
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    • 2003
  • A recent trend In flexible manufacturing systems (FMS) Is to utilize the Identical versatile machines with fast tool delivery devices. Unlike a conventional FMS where parts are fed to the machines with the required tools, tools are acquired from other machines using a tool delivery system and parts can be finished on the same machine In these FMS. Therefore it Is more important problem 4o plan tool flow using tool delivery system In these FMS rather than part flow In conventional FMS. According to the existing study, In FMS 20∼30 percent of the total management cost Is the cost related with tools and It Is possible to reduce the tool Inventory by 40 percent using efficient tool allocation. In this study, In FMS under dynamic tool allocation strategy, a new method of part release considering tool flow at the stage of part release Is proposed. In order to prove the efficiency of the proposed part release It is compared with other part release through simulation experiments. Performance measures in these experiments are the throughput and the number of tardy parts.

FMS에서 공구 상태를 고려한 부품투입 방법 (A Part Release considering Status of Tool in FMS)

  • 이충수;오형술;박경종
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2001년도 춘계학술대회 논문집
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    • pp.377-380
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    • 2001
  • A recent trend in flexible manufacturing systems(FMS) is to compose of the identical versatile-machines and to use dynamic tool allocation strategy, sharing tools between machines with fast tool delivery system. Unlike a conventional FMS where parts are fed to the machines with the required tools, tools are acquired from other machines using a tool delivery system and parts can be finished on the same machine in these FMS. Therefore it is more important problem to plan tool flow using tool delivery system in these FMS rather than part flow in conventional FMS. According to existing study, in FMS 20~30 percent of the total management cost is the cost related with tools and it is possible to reduce the tool inventory by 40 percent using efficient tool allocation. In this study, in FMS under dynamic tool allocation strategy, a new method of part release considering tool flow at the stage of part release is proposed. In order to prove the efficiency of the proposed part release it is compared with other part release through simulation experiments. Performance measures in these experiments are the throughput and the number of tardy parts.

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Glucose/Oxygen Deprivation Induces Release of $[^3H]5-hydroxytryptamine$ Associated with Synapsin 1 Expression in Rat Hippocampal Slices

  • Park, Eun-Mi;Chu, Sang-Hui;Lee, Kyung-Eun
    • The Korean Journal of Physiology and Pharmacology
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    • 제4권5호
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    • pp.347-353
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    • 2000
  • It has been well documented that a massive release of not only glutamate but also other neurotransmitters may modulate the final responses of nerve cells to the ischemic neuronal injury. But there is no information regarding whether the release of monoamines is directly associated with synaptic vesicular proteins under ischemia. In the present study, it was investigated whether synapsin 1, syntaxin and SNAP-25 are involved in the release of 5-hydroxytryptamine $([^3H]5-HT)$ in glucose/oxygen deprived (GOD) rat hippocampal slices. And, the effect of NMDA receptor using DL-2-amino-5-phosphonovaleric acid (APV) on ischemia- induced release of 5-HT and the changes of the above proteins were also investigated. GOD for 20 minutes enhanced release of $[^3H]5-HT,$ which was in part blocked by the NMDA receptor antagonist, APV. The augmented expression of synapsin 1 during GOD for 20 minutes, which was also in part prevented by APV. In contrast, the expression of syntaxin and SNAP-25 were not altered during GOD. These results suggest that ischemic insult induces release of $[^3H]5-HT$ associated with synapsin 1, synaptic vesicular protein, via activation of NMDA receptor in part.

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SSMS에서 동적 공구할당을 고려한 부품투입 알고리즘의 시뮬레이션 분석 (Simulation Analysis of Part Release Algorithm under Dynamic Tool Allocation in SSMS)

  • 이충수
    • 한국시뮬레이션학회논문지
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    • 제8권1호
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    • pp.63-76
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    • 1999
  • Recently in manufacturing environment, manufacturing order is characterized by unstable market demand, shorter product life cycle, a variety of product and shorter production lead time. In order to adapt this manufacturing order, flexible manufacturing systems(FMS) in manufacturing technology advances into the direction that machines become further versatile functionally and that tools are controlled by fast tool delivery device. Unlike conventional FMS to mainly focus on part flow, it is important to control tool flow in single-stage multimachine systems(SSMS), consisting of versatile machines and fast tool delivery device. This research is motivated by the thought that exact estimation of tool competition at part release in SSMS enhances the system performance. In this paper, in SSMS under dynamic tool allocation strategy to share tools among machines, we propose real-time part release and tool allocation algorithms which can apply real factory and which can improve system performance.

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ATP-Induced Histamine Release Is in Part Related to Phospholipase $A_2$-Mediated Arachidonic Acid Metabolism in Rat Peritoneal Mast Cells

  • Lee, Yun-Hye;Lee, Seung-Jun;Seo, Moo-Hyun;Kim, Chang-Jong;Sim, Sang-Soo
    • Archives of Pharmacal Research
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    • 제24권6호
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    • pp.552-556
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    • 2001
  • Histamine and arachidonic acid (AA) release was measured using the P2-purinoceptor antaongists, phospholipase $A_2{\;}(PLA_2)$ and cyclooxygenase (COX)/lipoxygenase (LOX) inhibitors to determine whether or not ATP-induced histamine release is associated with arachidonic acid (AA) release in rat peritoneal mast cells. ATP increased histamine release in a dose dependent manner, whereas adenosine did not. PPADS (a selective P2X-purinoceptor antagonist) and suramin (a nonselective P2X,2Y-purinoceptor antagonist) inhibited ATP-induced histamine release in a dose dependent manner. However, RB-2 (a P2Y-purinoceptor antagonist) did not block ATP-induced histamine release. Manoalide and oleyloxyethyl phosphorylcholine (OPC), secretory PLA$_2$ inhibitors, also inhibited ATP-induced histamine release dose-dependently. Both COX inhibitors (ibuprofen and indomethacin) and LOX inhibitors (baicalein and caffeic acid) inhibited ATP-induced histamine in a dose dependent manner. ATP significantly increased [$^3H$]AA release by 54%. PPADS and suramin significantly inhibited ATP-induced [3H]Ph release by 81% and 39%, respectively. ATP-induced histamine release was significantly inhibited by a variety of protein kinase inhibitors, such as bisindolmaleimide, genistein, methyl 2,5-dihydroxycinnamate, W-7 and trifluoperazine. Overall, the results suggest that ATP-induced histamine release is in part related to the PLA2-mediated AA metabolism and P2X-purinoceptors.

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Involvement of phospholipase $A_2$ in ATP-induced mucin release from cultured Hamster Tracheal Surface Epithelial cells

  • Jo, M.;Ko, K.H.;Kim, K.C.
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1996년도 춘계학술대회
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    • pp.219-219
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    • 1996
  • Mucin release from hamster tracheal surface epithelial(HTSE) cells can be stimulated by extracellular ATP via activation of P$_2$ purinoceptors located on the cell surface which appears to be coupled to phospholipase C via G proteins. However, our preliminary data indicate that the ATP-induced mucin release involves, in part, activation of PKC, but not an increase in the intracellular Ca++ level, suggesting the presence of another pathway which is separate from the PLC-PKC pathway, In this study, we intended to confirm the previous observation and subsequently identify an additional mechanism. Confluent HTSE cells were metabolically labeled with either $^3$H-glucosamine or $^3$H-arachidonic acid(AA), and release of either $^3$H-mucin or $^3$H-AA was quantified following various treatments. $^3$H-mucin was assayed using the sepharose CL-4B gel-filtration method, whereas $^3$H-AA liberation was measured by counting $^3$H-radioactivity in the chase medium. We found that: (1)Desensitization of PKC by pretreatment with PMA completely abolished the mucin releasing effect of PMA but partially inhibited the ATP-induced mucin release; (2) ATP increases release of $^3$H-AA in a dose-dependent fashion; (3) mepacrine, an inhibitor of PLA$_2$, attenuates ATP-induced mucin release in a dose-dependent fashion. These results confirm our previous notion that the PLC-PKC pathway is responsible, in part, for ATP-induced mucin release. Furthermore, activation of PLA$_2$ appears to be an additional pathway which is involved in ATP-induced mucin release.

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Aminoglycosides의 취효소 분비항진기전에 관한 연구 (Studies on the Enzyme-releasing Mechanism of Aminoglycosides from Pancreas)

  • 심호식;김경환;홍사석
    • 대한약리학회지
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    • 제19권1호
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    • pp.71-76
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    • 1983
  • Aminoglycoside antibiotics are reported to enhance the amylase release from isolated slices of pancreas in vitro and the mode of action of aminoglycosides on amylase release is considered different from those of acetylcholine or cholecystokinin(CCK), i.e., electronmicroscopically intact zymogen granules are appeared in the lumen of pancreatic acini by treatment of aminoglycosides. It is known that atropine blocks the secretagogue effect of acetylcholine, and phenoxybenzamine is reported to block the effects of CCK or its analogue caerulein. Present study was undertaken to investigate the mode of action of aminoglycosides on the amylase release using atropine, phenoxybenzamine and propranolol as a membrane stabilizing agent in slices of chicken pancreas. The results are summarized as follows : 1) Streptomycin and kanamycin increased the amylase release significantly from slices of chicken pancreas. 2) The effect of streptomycin was inhibited by atropine but not by phenoxybenzamine or propranolol. 3) The amylase release by acetylcholine was blocked by atropine tut the effect of cholecystokinin octapeptide(CCK-8) was not influenced by atropine, phenoxybenzamine or propranolol. 4) Pretreatment of streptomycin enhanced the secretagogue effect of acetylcholine or CCK-8. From these results it is suggested that amylase releasing effects of aminoglycosides are mediated in part by cholinergic stimulation and in part by membrane alteration and these effects are enhanced by acetylcholine or cholecystokinin.

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Hollywood Film Industry and the Changes in the Theatrical Release

  • Joo, Jeongsuk
    • International Journal of Advanced Culture Technology
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    • 제10권2호
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    • pp.181-186
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    • 2022
  • In this paper, we examine the shortening of the theatrical window whereby films play at theaters for 90 days as one of the most portentous issues that could reshape the Hollywood film industry. We first examine the windows system that protected the status of movie theaters and the studios' attempt to shorten the theatrical release to create a premium VOD window in response to the declining revenue of DVDs after 2007 and the rise of streaming services. We then look at some of the major disruptions in distribution COVID-19 brought about. We also explore the shortening of the theatrical release in the wake of the pandemic and shows the changes in the theatrical release, along with the expansion of streaming services, raise questions over the long-held primacy of the theatrical release and the definition of film with the theatrical release as its part. From this, we highlight Hollywood at the crossroads of major changes with its future less certain than ever before.

압축코팅법에 의한 3단계 약물방출형 지속성제제의 제조 및 용출특성 (Preparation and Dissolution Characteristics of the Compression-Coated Controlled Release Tablet Exhibiting Three-step Release)

  • 김철수;권혁노;차봉진;권종원;양중익;민신홍
    • Journal of Pharmaceutical Investigation
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    • 제22권2호
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    • pp.133-137
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    • 1992
  • A novel oral controlled release tablet which may offer more uniform drug level in the body than simple zero-order was developed. The tablet is composed of three layers; outer film layer, middle part compression-coated hydroxypropylmethylcellulose (HPMC) matrix layer, and inner core layer. Each layer contains nicardipine HCl as a model drug. In vitro dissolution test showed that the tablet released the drug in clear three steps; a rapid initial release, followed by a constant rate of release, and then a second phase of fast release of drug. The dissolution characteristics could be modified easily by changing the grade of HPMC, thickness of matrix layer, content of methylcellulose in matrix layer, content of active ingredient in each layer. The pH of dissolution medium did not affect the release profile. This three-step release system is expected to raise the blood concentration rapidly to effective level and to maintain effective blood level longer than simple slow-release systems.

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