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‣ Implantação de um sistema MRP em ambiente de produção enxuta com alta diversidade de componentes e sazonalidade; Deployment of MRP within an environment of lean production with high diversity of components and seasonality

Marques, Dani Marcelo Nonato
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 05/05/2008 Português
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Nenhum sistema ou lógica específica é a solução para todos os problemas de administração industrial. Desta forma as empresas estão adotando a integração entre lógicas e sistemas, no intuito de atingir melhores soluções. Entre outras miscigenações, as empresas estão buscando unir as lógicas dos MRP com os sistemas de produção enxuta. Portanto o objetivo deste trabalho é modelar a implantação de um sistema MRP (Material Requirement Planning), como parte da implantação de um ERP (Enterprise Resource Planning) em uma empresa produtora de implementos agrícolas, a qual possui o sistema de produção enxuta implantado desde 1998. Esta proposta está fundamentada na teoria da inovação, na teoria de redes, nos sistemas de produção enxuta, nos sistemas ERP (Enterprise Resource Planning) e nos sistemas híbridos de produção, os quais utilizam tanto componentes dos sistemas ERP, como o MRP neste caso, quanto conceitos de sistemas de produção enxuta. O recorte analítico de redes de inovação permite verificar as ligações e os relacionamentos entre empresas e entre os departamentos dentro da mesma corporação. A análise é realizada a partir do projeto de implantação do MRP, passando pela entrada do MRP no ar até a sua estabilização no ambiente produtivo. O ponto principal é que o sistema MRP auxilie as operações da empresa em agilidade no tempo de resposta sobre oscilações de demanda...

‣ Redução da instabilidade e melhoria de desempenho do sistema MRP

Godinho Filho,Moacir; Fernandes,Flavio Cesar Faria
Fonte: Associação Brasileira de Engenharia de Produção Publicador: Associação Brasileira de Engenharia de Produção
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2006 Português
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O artigo propõe um método para melhorar o desempenho do sistema MRP em um estudo de caso, uma grande empresa que produz materiais para escrita. O método é conseqüência de um levantamento bibliográfico e de características particulares do estudo de caso. Este método parte do princípio de que a melhoria de desempenho dos sistemas MRP é viabilizada pela redução no grau de instabilidade de tais sistemas e esta por sua vez só pode ser conseguida por meio de dois fatores-chave: i) uma correta parametrização do sistema e ii) um planejamento e programação da produção integrados voltados para a elaboração de um Plano Mestre de Produção (MPS) factível, respeitando as limitações de cálculo de capacidade do sistema. O método foi implementado e os resultados foram: uma redução drástica na instabilidade do sistema, com conseqüente redução nos custos dos estoques, melhoria no nível de serviço e aumento da satisfação e confiança das pessoas com relação ao sistema.

‣ Mutagenesis of SNM1, Which Encodes a Protein Component of the Yeast RNase MRP, Reveals a Role for This Ribonucleoprotein Endoribonuclease in Plasmid Segregation

Cai, Ti; Reilly, Tracey R.; Cerio, Michael; Schmitt, Mark E.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /11/1999 Português
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RNase MRP is a ribonucleoprotein endoribonuclease that has been shown to have roles in both mitochondrial DNA replication and nuclear 5.8S rRNA processing. SNM1 encodes an essential 22.5-kDa protein that is a component of yeast RNase MRP. It is an RNA binding protein that binds the MRP RNA specifically. This 198-amino-acid protein can be divided into three structural regions: a potential leucine zipper near the amino terminus, a binuclear zinc cluster in the middle region, and a serine- and lysine-rich region near the carboxy terminus. We have performed PCR mutagenesis of the SNM1 gene to produce 17 mutants that have a conditional phenotype for growth at different temperatures. Yeast strains carrying any of these mutations as the only copy of snm1 display an rRNA processing defect identical to that in MRP RNA mutants. We have characterized these mutant proteins for RNase MRP function by examining 5.8S rRNA processing, MRP RNA binding in vivo, and the stability of the RNase MRP RNA. The results indicate two separate functional domains of the protein, one responsible for binding the MRP RNA and a second that promotes substrate cleavage. The Snm1 protein appears not to be required for the stability of the MRP RNA, but very low levels of the protein are required for processing of the 5.8S rRNA. Surprisingly...

‣ Effects of Nonpolar Mutations in Each of the Seven Bacillus subtilis mrp Genes Suggest Complex Interactions among the Gene Products in Support of Na+ and Alkali but Not Cholate Resistance

Ito, Masahiro; Guffanti, Arthur A.; Wang, Wei; Krulwich, Terry A.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /10/2000 Português
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The Bacillus subtilis mrp (multiple resistance and pH) operon supports Na+ and alkali resistance via an Na+/H+ antiport, as well as cholate efflux and resistance. Among the individual mutants with nonpolar mutations in each of the seven mrp genes, only the mrpF mutant exhibited cholate sensitivity and a cholate efflux defect that were complemented by expression of the deleted gene in trans. Expression of mrpF in the mrp null (VKN1) strain also restored cholate transport and increased Na+ efflux, indicating that MrpF does not require even low levels of other mrp gene expression for its own function. In contrast to MrpF, MrpA function had earlier seemed to depend upon at least modest expression of other mrp genes, i.e., mrpA restored Na+ resistance and efflux to strain VK6 (a polar mrpA mutant which expresses low levels of mrpB to -G) but not to the null strain VKN1. In a wild-type background, each nonpolar mutation in individual mrp genes caused profound Na+ sensitivity at both pH 7.0 and 8.3. The mrpA and mrpD mutants were particularly sensitive to alkaline pH even without added Na+. While transport assays in membrane vesicles from selected strains indicated that MrpA-dependent antiport can occur by a secondary, proton motive force-dependent mechanism...

‣ Myeloid Cell Function in MRP-14 (S100A9) Null Mice

Hobbs, Josie A. R.; May, Richard; Tanousis, Kiki; McNeill, Eileen; Mathies, Margaret; Gebhardt, Christoffer; Henderson, Robert; Robinson, Matthew J.; Hogg, Nancy
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /04/2003 Português
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Myeloid-related protein 14 (MRP-14) and its heterodimeric partner, MRP-8, are cytosolic calcium-binding proteins, highly expressed in neutrophils and monocytes. To understand the function of MRP-14, we performed targeted disruption of the MRP-14 gene in mice. MRP-14−/− mice showed no obvious phenotype and were fertile. MRP-8 mRNA but not protein is present in the myeloid cells of these mice, suggesting that the stability of MRP-8 protein is dependent on MRP-14 expression. A compensatory increase in other proteins was not detected in cells lacking MRP-8 and MRP-14. Although the morphology of MRP-14−/− myeloid cells was not altered, they were significantly less dense. When Ca2+ responses were investigated, there was no change in the maximal response to the chemokine MIP-2. At lower concentrations, however, there was reduced responsiveness in MRP-14−/− compared with MRP-14+/+ neutrophils. This alteration in the ability to flux Ca2+ did not impair the ability of the MRP-14−/− neutrophils to respond chemotactically to MIP-2. In addition, the myeloid cell functions of phagocytosis, superoxide burst, and apoptosis were unaffected in MRP-14−/− cells. In an in vivo model of peritonitis, MRP-14−/− mice showed no difference from wild-type mice in induced inflammatory response. The data indicate that MRP-14 and MRP-8 are dispensable for many myeloid cell functions.

‣ Inhibition of Human Papillomavirus Type 16 E7 Phosphorylation by the S100 MRP-8/14 Protein Complex

Tugizov, Sharof; Berline, Jennifer; Herrera, Rossana; Penaranda, Maria Elena; Nakagawa, Mayumi; Palefsky, Joel
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /01/2005 Português
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The human papillomavirus type 16 (HPV16) E7 is a major viral oncoprotein that is phosphorylated by casein kinase II (CKII). Two S100 family calcium-binding proteins, macrophage inhibitory-related factor protein 8 (MRP-8) and MRP-14, form a protein complex, MRP-8/14, that inactivates CKII. The MRP-8/14 protein complex may inhibit CKII-mediated E7 phosphorylation and therefore may alter its interaction with cellular ligands and reduce E7 oncogenic activity. We examined the inhibitory effect of the MRP-8/14 complex on CKII activity and HPV16 E7 phosphorylation. We have shown that CKII activity and HPV16 E7 phosphorylation were inhibited by uptake of exogenous MRP-8/14 and activation of endogenous MRP-8/14. MRP-8/14-mediated inhibition of E7 phosphorylation occurred at the G1 phase of the cell cycle. Analysis of MRP expression in primary keratinocytes and in HPV16- and 18-transformed cervical and foreskin epithelial cell lines showed that expression of MRP-8, MRP-14, and the MRP-8/14 complex was detected only in primary untransformed keratinocytes and not in the HPV-infected immortalized epithelial cells. CKII activity in HPV-immortalized keratinocytes was approximately fourfold higher than in HPV-negative primary keratinocytes. Treatment of HPV-positive immortalized epithelial cells with exogenous MRP-8/14 resulted in E7 hypophosphorylation and complete inhibition of cell growth within 2 weeks...

‣ Expression of the MRP gene-encoded conjugate export pump in liver and its selective absence from the canalicular membrane in transport- deficient mutant hepatocytes

Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 01/10/1995 Português
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We have previously shown that the multi-drug resistance protein (MRP) mediates the ATP-dependent membrane transport of glutathione S- conjugates and additional amphiphilic organic anions. In the present study we demonstrate the expression of MRP in hepatocytes where it functions in hepatobiliary excretion. Analysis by reverse transcription- PCR of human and normal rat liver mRNA resulted in two expected cDNA fragments of MRP. Four different antibodies against MRP reacted on immunoblots with the glycoprotein of about 190 kD from human canalicular as well as basolateral hepatocyte membrane preparations. A polyclonal antibody directed against the carboxy-terminal sequence of MRP detected the rat homolog of MRP in liver. Double immunofluorescence microscopy and confocal laser scanning microscopy showed the presence of human MRP and rat Mrp in the canalicular as well as in the lateral membrane domains of hepatocytes. The transport function of the mrp gene- encoded conjugate export pump was assayed in plasma membrane vesicles with leukotriene C4 as a high-affinity glutathione S-conjugate substrate. The deficient ATP-dependent conjugate transport in canalicular membranes from TR- mutant rat hepatocytes was associated with a lack of amplification of one of the mrp cDNA fragments and with a selective loss of Mrp on immunoblots of canalicular membranes. Double immunofluorescence microscopy of livers from transport-deficient TR- mutant rats localized Mrp only to the lateral but not to the canalicular membrane. Our results indicate that the absence of Mrp or an isoform of Mrp from the canalicular membrane is the basis for the hereditary defect of the hepatobiliary excretion of anionic conjugates by the transport-deficient hepatocyte.

‣ Suppression of cell motility and metastasis by transfection with human motility-related protein (MRP-1/CD9) DNA

Fonte: The Rockefeller University Press Publicador: The Rockefeller University Press
Tipo: Artigo de Revista Científica
Publicado em 01/05/1993 Português
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Previously we showed that motility-related protein (MRP-1) is an antigen recognized by monoclonal antibody (mAb) M31-15 inhibiting cell motility and that the sequence of MRP-1 coincides with that of CD9. In the present study, plasmid was constructed in which human MRP-1/CD9 cDNA is expressed under the control of the Abelson murine leukemia virus promoter sequence. The expression plasmid for MRP-1/CD9 was introduced into Chinese hamster ovary cells, human lung adenocarcinoma cell line MAC10 (MRP-1 positive), and human myeloma cell line ARH77 (MRP-1 negative). All of the MRP-1/CD9 (over)expressing clones obtained from these transfected cells showed suppressed cell motility (penetration and phagokinetic track assays) depending on the degree of expression of MRP-1/CD9. Overexpression of MRP-1/CD9 by MAC10 cells resulted in the suppression of cell motility (maximally 73%) associated with considerable inhibition of the cell growth (maximally 48%). However, the inhibition of the growth of MAC10 cells by mAb M31-15 was < 17% at an antibody concentration of 1-5 micrograms/ml, which inhibits cell motility by > 90%. These results suggest that MRP-1/CD9 directly regulates cell motility and may also affect cell growth. Effects on metastasis by the expression of MRP-1 CD9 were investigated with mouse melanoma BL6 cells-BALB/c nu/nu mouse system. Metastatic potential of all transformants expressing MRP-1/CD9 was lower than that of parent BL6 cells.

‣ Single Gene Deletions of mrpA to mrpG and mrpE Point Mutations Affect Activity of the Mrp Na+/H+ Antiporter of Alkaliphilic Bacillus and Formation of Hetero-Oligomeric Mrp Complexes▿ †

Morino, Masato; Natsui, Shinsuke; Swartz, Talia H.; Krulwich, Terry A.; Ito, Masahiro
Fonte: American Society for Microbiology (ASM) Publicador: American Society for Microbiology (ASM)
Tipo: Artigo de Revista Científica
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Mrp antiporters catalyze secondary Na+(Li+)/H+ antiport and/or K+/H+ antiport that is physiologically important in diverse bacteria. An additional capacity for anion flux has been observed for a few systems. Mrp is unique among antiporters in that it requires all six or seven hydrophobic gene products (MrpA to MrpG) of the mrp operon for full antiporter activity, but MrpE has been reported to be dispensable. Here, the membrane complexes formed by Mrp proteins were examined using a cloned mrp operon from alkaliphilic Bacillus pseudofirmus OF4. The operon was engineered so that the seven Mrp proteins could be detected in single samples. Membrane extracts of an antiporter-deficient Escherichia coli strain expressing this construct were analyzed by blue native-sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Mrp complexes of two sizes were identified containing all seven Mrp proteins. Studies of the single nonpolar mrp gene deletions in the construct showed that a subcomplex of MrpA, MrpB, MrpC, and MrpD was formed in the absence of MrpE, MrpF, or MrpG. By contrast, MrpE, MrpF, and MrpG were not observed in membranes lacking MrpA, MrpB, MrpC, or MrpD. Although MrpA and MrpD have been hypothesized to be the antiporter proteins...

‣ Single Site Mutations in the Hetero-oligomeric Mrp Antiporter from Alkaliphilic Bacillus pseudofirmus OF4 That Affect Na+/H+ Antiport Activity, Sodium Exclusion, Individual Mrp Protein Levels, or Mrp Complex Formation*

Morino, Masato; Natsui, Shinsuke; Ono, Tomohiro; Swartz, Talia H.; Krulwich, Terry A.; Ito, Masahiro
Fonte: American Society for Biochemistry and Molecular Biology Publicador: American Society for Biochemistry and Molecular Biology
Tipo: Artigo de Revista Científica
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Mrp systems are widely distributed and structurally complex cation/proton antiporters. Antiport activity requires hetero-oligomeric complexes of all six or seven hydrophobic Mrp proteins (MrpA–MrpG). Here, a panel of site-directed mutants in conserved or proposed motif residues was made in the Mrp Na+(Li+)/H+ antiporter from an alkaliphilic Bacillus. The mutant operons were expressed in antiporter-deficient Escherichia coli KNabc and assessed for antiport properties, support of sodium resistance, membrane levels of each Mrp protein, and presence of monomeric and dimeric Mrp complexes. Antiport did not depend on a VFF motif or a conserved tyrosine pair, but a role for a conserved histidine in a potential quinone binding site of MrpA was supported. The importance of several acidic residues for antiport was confirmed, and the importance of additional residues was demonstrated (e.g. three lysine residues conserved across MrpA, MrpD, and membrane-bound respiratory Complex I subunits (NuoL/M/N)). The results extended indications that MrpE is required for normal membrane levels of other Mrp proteins and for complex formation. Moreover, mutations in several other Mrp proteins lead to greatly reduced membrane levels of MrpE. Thus, changes in either of the two Mrp modules...

‣ Mutagenesis of the putative nucleotide-binding domains of the multidrug resistance associated protein (MRP). Analysis of the effect of these mutations on MRP mediated drug resistance and transport

Center, Melvin S.; Zhu, Qichao; Sun, Hongwei
Fonte: Kluwer Academic Publishers Publicador: Kluwer Academic Publishers
Tipo: Artigo de Revista Científica
Publicado em /09/1998 Português
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Studies were conducted to examine the functional role of the nucleotide-binding domains of MRP in drug resistance and drug transport in isolated membrane vesicles. In vivo studies were conducted by preparing stable transfectants of HeLa cells with wild-type MRP cDNA or MRP cDNAs which had been mutated at certain nucleotide binding domains (NBD). Stable transfectants producing equivalent amounts of the MRP encoded protein P190 were used in this study. The results demonstrated that deletions in the C-motif of NBD1 or the A-motif of NBD2 have a pronounced effect in reducing resistance levels to chemotherapeutic agents. Certain single-site mutations in lysines in these same motifs also reduce IC50 values. It has also been observed that mutation of the MRP NBDs results in an increase in drug accumulation and a reduction in drug efflux. Additional studies have been carried out in which recombinant baculovirus containing either wild-type MRP or MRP containing mutated NBDs was prepared and used to infect SF21 insect cells. Using this system we have analyzed the effects of these mutations on in vitro transport of leukotriene C4 (LTC4) 17 β-estradiol 17 (β-D-glucuronide)(E217βG) and daunomycin in membrane vesicles prepared from baculovirus infected cells. The results demonstrate that deletions and site-specific mutations in MRP NBDs greatly reduce the ATP dependent transport of all three substrates. The results of these studies conducted both in vivo and in vitro demonstrate that the NBDs of MRP function in a cooperative manner and are critical for the transport activity of the MRP encoded protein P190. These studies also identify specific lysines in NBD1 and NBD2 which are important for optimal MRP activity.

‣ Previs??o em mrp usando a transforma????o de box-cox atrav??s do aplicativo glim, com aplica????o

Ramos, Edson Marcos Leal Soares; Konrath, Andr??a Cristina; Samohyl, Robert Wayne
Fonte: Universidade Federal do Rio Grande Publicador: Universidade Federal do Rio Grande
Tipo: Artigo de Revista Científica
Português
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The principal objective of this paper is to offer a quantitative methodology for making forecasts to be used as an essential ingredient for MRP. The forecasts are for an individual product and for the very short-term, which is usually one or two weeks before the delivery date. The forecasting equation is estimated through regression analysis, transforming the dependent variable through a Box-Cox transformation and taking into account tendency and several kinds of seasonality, in the week, the month and the year. The resulting equation is shown to be easy to program and place directly within the MRP computational software.

‣ Closed Loop Integration of MRP, Scheduling and Shop Floor Control

Karmarkar, Uday S. ; Shivdasani, Indur M.
Fonte: William E. Simon Graduate School of Business Administration, University of Rochester Publicador: William E. Simon Graduate School of Business Administration, University of Rochester
Tipo: Trabalho em Andamento
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True closed loop performance in an MRP system would imply that the component level releases produced by the system are realistic. In dynamic shops, this requires a finite capacity scheduling system. Such systems are becoming available; however, at present, there appears to be no commonly understood way of integrating them with MRP. In this paper we discuss the different approaches that are emerging. In particular, we discuss the approach taken with the scheduling system CLASS, which was specifically designed to co-ordinate with MRP systems. Integration of this system with existing MRP systems is described with examples.

‣ Análisis, implementación y documentación de la planificación de requerimientos de material MRP de los insumos asociados con el proceso de acuñación en la fábrica de moneda del Banco de la Republica

Lancheros Acevedo, Víctor Fabián; Herrera Castellanos, José Alejandro
Fonte: Pontifícia Universidade Javeriana Publicador: Pontifícia Universidade Javeriana
Tipo: bachelorThesis; Trabajo de Grado Pregrado Formato: Pdf
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En la Fábrica de la Moneda del Banco de la República se presenta una problemática en la actual planificación empírica de requerimientos de materiales, lo cual genera incertidumbre en el cumplimiento oportuno del abastecimiento de insumos, y por ende un incremento del riesgo de desabastecimiento y sobre stock. Para solucionar esto se desarrolla el modelo MRP (Material Requirements Planning), con el fin de mejorar el seguimiento de materiales e insumos a lo largo del proceso, obteniendo así un plan de compras acorde a los requerimientos de producción. Con la gestión correcta del inventario en el almacén de la Fábrica de la Moneda mediante un manejo apropiado de la información en SAP, se busca lograr la correcta adquisición de los insumos y materias primas en los tiempos y cantidades requeridas.; In the Central Bank of Colombia´s Factory of currency a problem in the current empirical materials requirements is taking place. This generates uncertainty in the appropriate materials supply compliance, causing an increase in the shortage and overstock risk. To solve the problem, the MRP (Material Requirements Planning) model is developed. Its task is to improve the materials and supplies monitoring along the process, in order to obtain a purchase plan according to the production requirements. A right inventory administration in the Factory of currency´s wharehouse by means of an appropriate usage of the SAP information...

‣ Multidrug Resistance-Proteine in humanen malignen Gliomen. Expression, funktionelle Aktivität und Regulation durch p53; Multidrug resistance proteins in human malignant gliomas. Expression, functional activity and modulation by p53

Bähr, Roy Oliver
Fonte: Universidade de Tubinga Publicador: Universidade de Tubinga
Tipo: Dissertação
Português
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Die molekularen Mechanismen der Resistenz maligner Gliome gegenüber Chemotherapie sind nicht geklärt. Bisher wurde kein Parameter gefunden, der die Subgruppe an Patienten identifiziert, die von der Chemotherapie profitieren. Trotz vieler Jahre der Forschung zur Bedeutung des MDR-Mechanismus bei der Therapieresistenz maligner Hirntumoren ist diese Frage nur ungenügend beantwortet. Die vorliegende Arbeit liefert eine systematische Analyse des MDR-Phänomens in einer großen repräsentativen Gruppe humaner maligner Gliomzellinien. Die Expression von mdr-1/P-gp und mrp-1/MRP1 wurde auf mRNA- und Proteinebene mitttels RT-PCR und Durchflußzytometrie und auf funktioneller Ebene mittels Fluoreszenz-Transport untersucht. Außerdem wurde mittels P-gp/MRP-Inhibitoren die Möglichkeit untersucht, in vitro die Chemosensitivität maligner Gliomzellen zu verstärken. Es hat sich gezeigt, dass die meisten Gliomzellinien entweder über P-gp- oder MRP-Aktivität oder beides verfügen und auf die Hemmung der P-gp/MRP-Aktivität mit erhöhter Sensitivität für spezifische Zytostatika reagieren. Das Spektrum der Zytostatika, deren Wirkung durch P-gp- oder MRP-Inhibitoren potenziert wird, bestätigte frühere Arbeiten an nicht-glialen Zellen. Frühere Untersuchungen...

‣ MRP OPTIMIZATION MODEL FOR A PRODUCTION SYSTEM WITH REMANUFACTURING

Raupp,Fernanda M.P.; Angeli,Katharine De; Alzamora,Guina G.S.; Maculan,Nelson
Fonte: Sociedade Brasileira de Pesquisa Operacional Publicador: Sociedade Brasileira de Pesquisa Operacional
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2015 Português
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Science and technology practitioners have been studying how to take economical, social and environmental advantage of industrial residuals and discarded products. In this sense, this paper presents a Material Requirements Planning (MRP) optimization model for a particular production system that, besides manufacturing a final product and its main assembling component, it recovers units of the component from units of the returned product as well. It is assumed that the demand for the final product is independent of the amount of the returned product available, and that the market for the final product is not segmented. Considering that all parameters of the MRP mathematical model have deterministic nature, we prove that this production planning problem is NP-hard. We also show computational experiments with the model using an optimization solver and analyze some possible industrial scenarios, as well.

‣ Suitability of MRP II to material planning for component repair at Naval Aviation Depot, North Island.

O'Brien, Timothy J.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: x, 115 p.;28 cm.
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Approved for public release; distribution is unlimited; Manufacturing Resource Planning (MRP II) is being implemented at Naval Aviation Depot, North Island (NADEP NI) to combat chronic material deficiencies. MRP II is a planning tool designed for scheduling manufacturing activities with known demand. NADEP NI is a job shop component repair facility with component forecast error ranging up to 800 percent, making the suitability of MRP II questionable. This research studies material planning at NADEP NI to identify forecast error, probability of part replacement error, and material lead-time variability in order to make recommendations for success in implementing MRP II. Fifteen percent of requisitions for work-in-process components are between one and two years old. If lead-times are reduced to a maximum of one year, the planning horizon can be reduced. Work-in-process inventories can also be reduced by 2.3 million dollars based on 26 components sampled from the top revenue generators. Currently material is ordered five weeks prior to the repair quarter. Ordering material when the forecast is generated can reduce work-in-process inventories by 6.2 million dollars for the sample components; http://www.archive.org/details/suitabilityofmrp00obri; Lieutenant Commander...

‣ Analysis of historical Materiel Return Program (MRP) credits at the 1st Marine Logistics Group Reparable Issue Point (RIP)

Caricato, Edward M.; Draper, John D.
Fonte: Monterey, California. Naval Postgraduate School Publicador: Monterey, California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xx, 91 p. : col. ill. ; 28 cm.
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Approved for public release; distribution is unlimited; Materiel Returns Program (MRP) credits have increased 1st Marine Logistics Group's (1st MLG) total obligation authority by an average of 27% annually since 2008. However, 1st MLG has been unable to leverage the MRP in budget execution due to an inability to forecast future credits. The purpose of this research is to determine whether analysis of historical MRP credits at 1st MLG could enable the comptroller to forecast future credits, which would enable 1st MLG to leverage MRP credits and budget more efficiently in a constrained fiscal environment. This research utilized descriptive analysis of historical credits to identify systemic patterns or trends associated with MRP. The analysis of MRP credits focused on two specific areas: (1) the accuracy of credit estimates provided by the sources of supply (SOSs), and (2) the amount of time it took for 1st MLG to receive the actual credit. The primary finding of this research was that 1st MLG should be able to forecast MRP credits. The research showed that historically over a two-year period, SOSs accurately estimated credits 88.3% of the time and SOSs issued 95% of all actual credits within 90 days of 1st MLG submitting an item into MRP.; Outstanding Thesis; US Marine Corps (USMC) authors

‣ Reference model for implementing an MRP system in a highly diverse component and seasonal lean production environment

Marques, Dani Marcelo Nonato; Guerrini, Fabio Muller
Fonte: TAYLOR & FRANCIS LTD; ABINGDON Publicador: TAYLOR & FRANCIS LTD; ABINGDON
Tipo: Artigo de Revista Científica
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Companies are currently choosing to integrate logics and systems to achieve better solutions. These combinations also include companies striving to join the logic of material requirement planning (MRP) system with the systems of lean production. The purpose of this article was to design an MRP as part of the implementation of an enterprise resource planning (ERP) in a company that produces agricultural implements, which has used the lean production system since 1998. This proposal is based on the innovation theory, theory networks, lean production systems, ERP systems and the hybrid production systems, which use both components and MRP systems, as concepts of lean production systems. The analytical approach of innovation networks enables verification of the links and relationships among the companies and departments of the same corporation. The analysis begins with the MRP implementation project carried out in a Brazilian metallurgical company and follows through the operationalisation of the MRP project, until its production stabilisation. The main point is that the MRP system should help the company's operations with regard to its effective agility to respond in time to demand fluctuations, facilitating the creation process and controlling the branch offices in other countries that use components produced in the matrix...

‣ Programación matemática difusa aplicada en la planeación de requerimientos de material (MRP)

Arango Serna,Martín Darío; Urán Serna,Conrado Augusto; Pérez Ortega,Giovanni
Fonte: Facultad de Ingeniería, Universidad del Zulia Publicador: Facultad de Ingeniería, Universidad del Zulia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/04/2010 Português
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Un enfoque racional para la toma de decisiones debe tener en cuenta la subjetividad humana, en lugar de emplear sólo medidas con distribución de probabilidad. Esta actitud hacia la incertidumbre del comportamiento humano ha llevado al estudio de un relativamente nuevo campo de análisis de decisión como es, la toma de decisiones difusas, la cual incorpora la subjetividad y la imprecisión en la formulación de modelos y procesos de solución y representa una atractiva herramienta de ayuda a la investigación en ingeniería industrial cuando la dinámica de las decisiones están limitadas por imprecisiones en los modelos formulados. El presente artículo hace un resumen de las aplicaciones que ha tenido la lógica difusa en el campo industrial y presenta un modelo MRP al cual se aplican algunos de estos conceptos