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951.
The paper covers the main principles of setting up and the function of the Russian system of metrological assurance of analytical
measurements for the production of light alloys and superalloys.
Received: 20 October 1998 / Accepted: 9 November 1998 相似文献
952.
Due to the complexity of the scene, target detection in forward-looking infrared (FLIR) imagery is a challenging problem, especially for occluded target. The main contribution of this paper is to propose an indirect detection method for improving the recognition probability and effectiveness of target detection method in FLIR image sequences under complex conditions. The proposed method mainly includes four steps: preparation of forward-looking reference image of landmark, extraction of the real-time scene image, template matching and target location, in which some key technologies are proposed, such as perspective transformation used to solve projective problems, position prediction for improving real-time performance, and target location used for identifying the target’s position. Experimental results are shown to demonstrate the robustness and efficiency of proposed method in FLIR image sequences. 相似文献
953.
We formulate a model for the optimal location of switches in ATM communications networks. The networks are designed in such
a way that, at their arrival to the switches, ATM cells find free space in a buffer of length b, with a probability α. The
model avoids the impairment to the communication caused by both cell loss (because of shorter buffers) and cell-delay variations
(because of longer buffers). It is also shown how to transform a non-linear, probabilistic, constraint into a linear form.
Computational experience is provided for the model.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
954.
We present a region of interest (ROI) generation method specialized for nighttime pedestrian detection using far-infrared (FIR) images. Because pedestrians typically appear brighter than background in FIR images, previous research efforts primarily attempted to extract ROIs based on the intensity threshold. However this approach has problems resulting from the intensity variances of pedestrians due to their clothing and, especially in urban scenarios, and other heat sources that emit more heat than the pedestrians. In this paper, we propose a novel ROI generation method that is based on combining image segments instead of using the intensity threshold. In order to minimize dependence on brightness, we utilize the low-frequency characteristics of FIR images. As a result, our proposed method generates a small number of ROIs at an acceptable miss rate and the generated ROIs provide advantages for classification because the pedestrians are satisfactorily arranged within a bounding box. Experiments conducted indicate that our proposed method performs reliably in urban scenarios. 相似文献
955.
离子色谱荧光检测法测定废水中痕量2-氨基联苯和4-氨基联苯 总被引:2,自引:0,他引:2
采用离子色谱荧光检测法测定废水中的2-氨基联苯(2-ADP)和4-氨基联苯(4-ADP),流动相为1.0mL/min的0.06mol/L NaCl,0.08mol/L HCl,40%(V/V)ACN,分离柱为Dinoex OmniPac PCX-500,该法具有良好的重现性和线性关系,2-ADP和4-ADP的回收率分别为98.5%-101.4%和102.2%-104.0%,检测限分别为0.006mg/L和0.10mg/L。 相似文献
956.
DMAIC流程在自动焊接质量改进中的应用 总被引:1,自引:0,他引:1
本文按照六西格玛DMIAC流程对A企业自动焊接质量进行改进.按照DMAIC流程对问题进行定义,明确改进目标。然后测定导致自动焊质量问题的可能原因,并对相关测量系统的能力进行评定和改进.在此基础上进一步分析导致质量问题的根本原因,并设计了一个2~((-2))试验方案,找出影响焊接缺陷的显著因素并进行优化,使得自动焊过程的缺陷水平降为DPHU低于0.05,超过了预期目标,成本节省显著。最后,为了保持改进成果,对过程建立了适当的在控制方法. 相似文献
957.
《Journal of separation science》2003,26(18):1635-1642
Capillary electrochromatography using a monolithic matrix was employed to develop a rapid and highly efficient separation methodology for the analyses of mixtures of agrochemical importance. Using this method, ppm‐ppb detection limits for urea, carbamate, and phenoxy acid herbicides were achieved without a preconcentration technique. The detection limits were further decreased to low‐ppb levels for the same class of compounds using an on‐column preconcentration technique. 相似文献
958.
A continuous sampling plan is a set of rules that provide a given Average Outgoing Quality (AOQ), ideally with the minimum of effort (as measured by the Average Fraction Inspected, or AFI). Most such plans are based on the assumption that the quality (either defective or not) of successive production units is uncorrelated. In this paper, we explore the impact of correlation in the production process on the design of a sampling plan when it is not possible to inspect long runs of production unit-by-unit. We shall generalize Dodge's continuous sampling plan on two counts, replacing Level 1 100% inspection by 100fo% inspection, and considering the production process to be Markov dependent instead of consisting of independent Bernoulli trials. We derive formulae for the AOQ and AFI, and consider how best to choose the sampling plan parameters in the presence of nonzero correlation. 相似文献
959.
960.
For more than three decades the International Atomic Energy Agency (IAEA) has supported projects on food, nutrition and environment
for strengthening the analytical capabilities in developing countries (DCs). Over time, such efforts have led to the development
of proper study designs, harmonization of sampling protocols, adequate contamination control and evaluation of the suitability
of competing analytical techniques for the determination of specific analytes. Collectively, these consistent IAEA initiatives
have promoted harmonization of chemical measurements thus facilitating comparability of results of filed investigations. Importantly,
the Agency's efforts have infused a measure of metrological awareness in measurements carried out in field studies, including
physiological measurements. Nuclear and isotopic techniques have played an important role in reaching these goals by establishing
reliable measurement processes for application in health care studies. 相似文献