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With the pressure of intensive global competition and the trend of shortening product life-cycle, the procedure for new product development (NPD) has become the focus of business concerns and investment of large corporations and the key strategy to upgrade competitiveness of corporations. An effective NPD procedure can meet the demands on quality, time-to-delivery and cost limitations of a corporation. Measuring and analysing the performance of the existing NPD procedure and pinpointing and resolving the problems of the existing NPD procedure is the key to improve the NPD performance to meet a corporation's demands. Six Sigma is a systemic procedure commonly used to improve product quality. This paper proposes a model to evaluate and improve the performance of NPD procedures by following the systemic procedure of Six Sigma and applying criteria defined by application of performance matrix, factor analysis, and theory of constraints. The resulting model is then verified with real life NPD procedures from a certain semi-conductor equipment manufacturer such that corporative competitiveness can be enhanced through the elevating cycle of performance evaluation, problem excavation, causes analysis, and countermeasure determination and execution proposed by this paper.  相似文献   

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The effect of Ni on the thermal conductivity and fluidity of a low Si-added Al–Si casting alloy was investigated. The room temperature thermal conductivity of an Al–2 wt%Si alloy instantly dropped when adding 0.5 wt%Ni, whereas further additions of Ni up to 3 wt% had little influence on the thermal conductivity, which was in the range of 180–185 W/mK. The thermal conductivity was also estimated for the alloys cast at various cooling rates by measuring the electrical conductivity using the Wiedemann–Franz law and increased nearly linearly with an increase in the cooling rates. At such a low level of 2 wt%Si, the castability of the Al–Si alloys, which was evaluated by a fluidity spiral test, was enhanced by the Ni additions, exhibiting the maximum fluidity length at 0.5 wt%Ni.  相似文献   

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Since the 1990s, the scope of research evaluation has widened to encompass the societal products (outputs), societal use (societal references) and societal benefits (changes in society) of research. Research evaluation has been extended to include measures of the (1) social, (2) cultural, (3) environmental and (4) economic returns from publicly funded research. Even though no robust or reliable methods for measuring societal impact have yet been developed. In this study, we would like to introduce an approach which, unlike the currently common case study approach (and others), is relatively simple, can be used in almost every subject area and delivers results regarding societal impact which can be compared between disciplines. Our approach to societal impact starts with the actual function of science in society: to generate reliable knowledge. That is why a study (which we would like to refer to as an assessment report) summarising the status of the research on a certain subject represents knowledge which is available for society to access. Societal impact is given when the content of a report is addressed outside of science (in a government document, for example).  相似文献   

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Abstract

We make a semi-classical steady state analysis of the influence of mirror motion on the quantum phase transition for an optomechanical Dicke model in the thermodynamic limit. An additional external mechanical pump is shown to modify the critical value of atom–photon coupling needed to observe the quantum phase transition. We further show how to choose the mechanical pump frequency and cavity–laser detuning to produce extremely cold condensates. The present system can be used as a quantum device to measure weak forces.  相似文献   

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Analysis and design of a Ka‐band (20‐GHz) satellite offset‐fed shaped reflector antenna with a single feed for producing a contoured beam to cover the Taiwan region is presented. The design of this shaped reflector antenna is for future geostationary (GEO) satellite communication or DBS (direct broadcasting satellite) applications to serve the Taiwan region. The geometrical optics (GO)/aperture field (AF) method and aperture phase optimization procedures are employed for reflector surface shaping to produce the desired contoured beam. The physical optics (PO) method is used to accurately calculate the far‐field radiation pattern. Numerical simulation results show that the designed shaped reflector produces a Taiwan region converge beam and effectively reduces the antenna gain level in the nearby area of mainland China. Further reduction of the antenna gain level can be achieved by shifting the boresight direction of the satellite antenna for a certain small angle.  相似文献   

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A recent review article critically assessed the effectiveness of published research articles in nanotoxicology to meaningfully address health and safety issues for workers and consumers. The main conclusions were that, based on a number of flaws in study designs, the potential risk from exposures to nanomaterials is highly exaggerated, and that no ‘nano-specific’ adverse effects, different from exposures to bulk particles, have been convincingly demonstrated. In this brief editorial we focus on a related tangential issue which potentially compromises the integrity of basic risk science. We note that some single investigation studies report specious toxicity findings, which make the conclusions more alarming and attractive and publication worthy. In contrast, the standardized, carefully conducted, ‘guideline study results’ are often ignored because they can frequently report no adverse effects; and as a consequence are not considered as novel findings for publication purposes, and therefore they are never considered as newsworthy in the popular press. Yet it is the Organization for Economic Cooperation and Development (OECD) type test guideline studies that are the most reliable for conducting risk assessments. To contrast these styles and approaches, we present the results of a single study which reports high toxicological effects in rats following low-dose, short-term oral exposures to nanoscale titanium dioxide particles concomitant with selective investigative analyses. Alternatively, the findings of OECD test guideline 408, standardized guideline oral toxicity studies conducted for 90 days at much higher doses (1000 mg kg−1) in male and female rats demonstrated no adverse effects following a very thorough and complete clinical chemical, as well as histopathological evaluation of all of the relevant organs in the body. This discrepancy in study findings is not reconciled by the fact that several biokinetic studies in rats and humans demonstrate little or no uptake of nanoscale or pigment-grade TiO2 particles following oral exposures. We conclude that to develop a competent risk assessment profile, results derived from standardized, guideline-type studies, and even ‘no effect’ study findings provide critically useful input for assessing safe levels of exposure; and should, in principle, be readily acceptable for publication in peer-reviewed toxicology journals. This is a necessary prerequisite for developing a complete dataset for risk assessment determinations.  相似文献   

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An experimental method is presented for the determination of the total efficiency and the response function of a γ-ray detector in the range 0.5–10 MeV. It consists of observing (p, γ) resonance reactions with two detectors: the one to be calibrated, in this case a cylindrical deuterated hexabenzene liquid scintillator, and a Ge detector used to select and resolve the main two-step cascades of the reaction. Efficiencies and response functions were obtained for thirteen γ-rays via the coincidence method, using targets of 26Mg at proton energies of 1001 and 2220 keV, of 30Si at 1398 keV and of 34S at 1211 keV.The weighting function derived from these data was used to determine the capture area of the 1.15 keV neutron resonance in 56Fe. By normalizing the data to the 5.2 eV resonance in 109Ag, a value (nΓγ/Γ) = 57.1 ± 2.1 meV was obtained, in excellent agreement with the result of recent transmission measurements.  相似文献   

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The steroidal pig pheromones androstenone (5α-androst-16-en-3-one), 3α-androstenol (5α-androst-16-en-3α-ol), and 3β-androstenol (5α-androst-16-en-3β-ol) as well as the heterocyclic aromatic amines skatole and indole, originating from microbial degradation of tryptophan in the intestine of pigs, are frequently recognized as the major compounds responsible for boar taint. A new procedure, applying stable isotope dilution analysis (SIDA) and headspace solid-phase microextraction-gas chromatography/mass spectrometry (HS-SPME-GC/MS) for the simultaneous quantitation of these boar taint compounds in pig fat was developed and validated. The deuterated compounds androstenone-d(3), 3β-androstenol-d(3), skatole-d(3), and indole-d(6) were synthesized and successfully employed as internal standards for SIDA. The new procedure is characterized by a fast, simple, and economic sample preparation: methanolic extraction of the melted fat followed by a freezing and an evaporation step allows for extraction and enrichment of all five analytes. Additional time-consuming cleanup steps were not necessary, as HS-SPME sampling overcomes fat-associated injector and column contamination. The method has been validated by determining intra- and interday precision and accuracy as well as the limit of detection (LOD) and limit of quantitation (LOQ). Additionally, a cross-validation for androstenone, skatole, and indole was carried out comparing the results of 25 back fat samples obtained simultaneously by the new SIDA-HS-SPME-GC/MS procedure with those obtained in separate GC/MS and high-performance liquid chromatography fluorescence detection (HPLC-FD) measurements. The cross-validation revealed comparable results and confirms the feasibility of the new SIDA-HS-SPME-GC/MS procedure.  相似文献   

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