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1.
Production planning and control (PPC) systems that employ aspects from both make-to-order (MTO) and make-to-stock (MTS) production control are known as hybrid MTS/MTO systems. While both MTO and MTS separately have been studied extensively, their combined use has received less attention. However, the literature on this topic is growing and this paper shows that the review performed in this paper is an important addition to the field. We categorise relevant literature according to a novel taxonomy and show that hybrid MTS/MTO production control can be used in different contexts. In addition, an overview of the modelling techniques and methods used in these papers is provided. Based on the reviewed literature, relevant research questions and directions for future research are identified. Finally, it is shown that hybrid MTS/MTO production control is prevalent in practice by discussing research with industrial applications. The paper contains an overview of research on hybrid MTS/MTO production control to be used as reference for researchers active in the field, and provides managerial insights and directions for future research on this topic. 相似文献
2.
Frank te Beest Ad Peeters Kees van Berkel Hans Kerkhoff 《Journal of Electronic Testing》2003,19(4):397-406
Handshake circuits form a special class of asynchronous circuits that has enabled the industrial exploitation of the asynchronous potential such as low power, low electromagnetic emission, and increased cryptographic security. In this paper we present a test solution for handshake circuits that brings synchronous test-quality to asynchronous circuits. We add a synchronous mode of operation to handshake circuits that allows full controllability and observability during test. This technique is demonstrated on some industrial examples and gives over 99% stuck-at fault coverage, using test-pattern generators developed for synchronous circuits. The paper describes how such a full-scan mode can be achieved, including an approach to minimize the number of dummy latches in case latches are used in the data path of the handshake circuit. 相似文献
3.
The aim of this work was to develop sustained local release systems for radioiodinated iodo-2'-deoxyuridine (125IUdR) from biodegradable polymeric microspheres to facilitate the controlled delivery of 125IUdR to brain tumours. The selective uptake of IUdR into the cell nucleus results in cell disruption over the short range of the low energy Auger electrons. The biodegradable microspheres can be precisely implanted in the brain by stereotactic techniques and the IUdR within the microspheres is protected from degradation and thus a sustained source of radiolabelled IUdR is available in the vicinity of the residual tumour cells. Poly(lactic-co-glycolic acid), PLGA (85:15), microspheres containing cold IUdR and the Auger-electron emitter 125I, as 125IUdR were prepared using the O/W, O/O and W/O/W emulsion-solvent evaporation methods. The W/O/W emulsion method was most effective in achieving good drug loading with the use of bovine plasma in the internal water phase. Also effective in improving the drug loading was the use of 20% acetone in the dichloromethane and the presence of Span 40 in the organic phase. Electrolytes (NaCl and IUdR) in the external aqueous phase also improved drug loading. After an initial rapid release from the microspheres, a sustained release was observed over 15 days for the 'cold' IUdR. The sustained release portions of the release curves showed Higuchi (t1/2), diffusion controlled release kinetics. The radiolabelled IUdR microspheres showed a burst release effect of 30-40% followed by a sustained release over 35 days. 相似文献
4.
MF Chen YY Jan CS Wang TL Hwang LB Jeng SC Chen TC Chao 《Canadian Metallurgical Quarterly》1997,84(9):1229-1232
The effect of phenylephrine-induced reflex parasympathetic stimulation on QT interval and its dispersion was studied in 16 healthy subjects with a history of paroxysmal supraventricular tachycardia, both during sinus rhythm and during atrial pacing. Results demonstrate that rapid reflex parasympathetic stimulation does not influence QT interval duration or QT dispersion, and also emphasize the inappropriateness of Bazett's formula, the need for comparison of QT intervals during identical heart rates, and the importance of analyzing all 12 leads of a standard electrocardiogram when assessing the effects of various interventions on the QT interval. 相似文献
5.
PI Lobo C Spencer MT Douglas WC Stevenson TL Pruett 《Canadian Metallurgical Quarterly》1993,55(5):1063-1066
Recent reports indicate a higher incidence of both acute and chronic liver allograft rejection when, at the time of transplantation, the recipients serum contains donor-specific anti-HLA antibodies. From 9/89 to 5/91, 133 liver allografts were performed at our institution. Thirteen liver recipients had donor-specific IgG anti-HLA antibodies (complement-fixing) at the time of transplantation. In eleven patients, antibodies reacted to donor class I antigens while in 1 patient the donor-specific antibody had class II reactivity. Twelve patients have been followed for a minimum of 12 months (median 18 months, range 28-12 months). No hyperacute rejection was seen in any of the cases and four patients had acute rejections. Thus far only one of the twelve patients has biopsy evidence suggestive of chronic liver injury. The remaining have normal liver enzymes and bilirubin. Three of these twelve patients died (one from a myocardial infarction and the others from sepsis) accounting for a one-year graft survival of 75%. There was no significant statistical difference in the one-year graft survival in those recipients without donor-specific antibodies (i.e., 80.5%). In eight of the twelve patients, pretransplant preformed antibody level (PRA) was > 50%. In six of the thirteen patients donor-specific antibody was present at dilutions greater than 1:64. As previously reported, the donor-specific antibody disappeared from the serum posttransplant within hours and did not reappear. In vitro studies demonstrated no factor in portal or hepatic artery blood that could inhibit rabbit complement mediated lysis of anti-HLA antibodies. We conclude that it is not a contraindication to do liver transplants in the presence of donor-specific anti-HLA antibodies. 相似文献
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BACKGROUND: Despite recognition of the high prevalence of alcoholism among patients with head and neck cancer, the prognostic importance of alcoholism has not been evaluated adequately. Previous investigators have speculated that alcoholic patients may have a poorer prognosis than nonalcoholic patients because of more advanced stage of cancer, the immunosuppressive effects of alcohol, and an increased rate of death due to other alcohol-related diseases. PURPOSE: The goal of this population-based study was to identify the features of alcoholism that are associated with survival for patients with head and neck cancer and to develop an alcoholic severity staging system from a composite of the independent features of alcoholism. METHODS: This prospective study included 649 patients who were diagnosed with cancer of the oral cavity, oropharynx, hypopharynx, or larynx during the period from September 1, 1983, through February 28, 1987, in a three-county area of western Washington state that participates in the Surveillance, Epidemiology, and End Results Program of the U.S. National Cancer Institute. Details on lifetime alcohol consumption, treatment for alcoholism, abstinence from alcohol prior to the diagnosis of cancer, and alcohol-related health problems were ascertained through in-person interviews near the time of diagnosis. Patients were classified as either nonalcoholics or alcoholics according to their responses to questions from the Michigan Alcoholism Screening Test. The measures of alcohol consumption and abuse that were found to be independently associated with 5-year survival by logistic regression analysis were combined using conjunctive consolidation to create a final composite variable, called an alcoholic severity stage. Cox proportional hazards regression analysis was done to estimate the relative risk (R) of death within 5 years due to specific causes of death for each of the alcoholic severity stages. RESULTS: Alcoholism (RR = 2.06; 95% confidence interval [CI] = 1.43-2.98) and a history of alcohol-related systemic health problems (i.e., liver disease, pancreatitis, delirium tremens, or seizures) (RR = 2.76; 95% CI = 1.69-4.49) were associated with an increased risk of death, whereas abstinence (i.e., the consumption of fewer than one drink per week at 1 year prior to the diagnosis of cancer) (RR = 0.62; 95% CI = 0.39-0.97) was associated with a decreased risk of death. These associations were independent of age, site of cancer, anatomical stage, histopathologic grade, smoking, and type of antineoplastic treatment. Patients in the two worst alcoholic severity stages had an increased risk of dying not only of head and neck cancer but also of cardiovascular disease, pulmonary disease, and other alcohol-related causes. CONCLUSIONS: Alcohol abuse, measured by alcohol consumption, functional impairment, a history of alcohol-related health problems, or abstinence, can provide important prognostic information for patients with head and neck cancer. Our results suggest that sobriety among alcoholic patients can lead to prolonged survival. 相似文献
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9.
PURPOSE: To demonstrate a superselective intraarterial chemotherapy as a therapeutic alternative in the treatment of previously treated recurrent lymph node metastases in breast cancer. METHODS: 14 patients with recurrent lymph node metastases in cases of breast cancer were presented to be treated by intraarterial chemotherapy of 25 mg mitoxantrone/m2 over a period of 24 hours. In two patients with superclavicular lymph node involvement an intraarterial therapy could not be carried out because of a vascular connection to the anterior spinal artery. Involved lymph stations could be reached in superselective technique by side branches of the subclavian artery. Heparin coverage was given intravenously. Every patient had had surgery, radiation, systemic chemo- and hormonal therapy before and was now graded as inoperable. Therapy indication was given by local tumour-induced symptoms. RESULTS: In the 12 treated cases complete remission was seen in three, partial remission in 4, a steady state in two and a progressive disease in three. There were no complications or severe side effects. CONCLUSION: Intraarterial chemotherapy is an effective and well tolerated treatment in recurrent lymph node metastases in cases of breast cancer even if conventional therapies can no longer be used. 相似文献
10.
TL Holyoake MG Freshney L McNair AN Parker PJ McKay WP Steward E Fitzsimons GJ Graham IB Pragnell 《Canadian Metallurgical Quarterly》1996,87(11):4589-4595
The characterization of many cytokines involved in the control of hematopoiesis has led to intense investigation into their potential use in ex vivo culture to expand progenitor numbers. We have established the optimum ex vivo culture conditions that allow substantial amplification of transient engrafting murine stem cells and which, simultaneously, augment the ability to sustain serial bone marrow transplantation (BMT). Short-term incubation of unfractionated BM cells in liquid culture with stem cell factor (SCF) and interleukin-11 (IL-11) produced a 50-fold amplification of clonogenic multipotential progenitors (CFU-A). Following such ex vivo expansion, substantially fewer cells were required to rescue lethally irradiated mice. When transplanted in cell doses above threshold for engraftment, BM cells expanded ex vivo resulted in significantly more rapid hematopoietic recovery. In a serial transplantation model, unmanipulated BM was only able to consistently sustain secondary BMT recipients, but BM expanded ex vivo has sustained quaternary BMT recipients that remain alive and well more than 140 days after 4th degree BMT. These results show augmentation of both short-term recovery posttransplant and the ability to serially transplant marrow by preincubation in culture with SCF and IL-11. 相似文献