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51.
We compared the data from four growth hormone (GH) immunoassays for analyzing 24-h GH profiles in four apparently normal subjects and four obese subjects (508 serum samples). The detection limit was 0.02 microgram/L for one immunochemiluminometric assay (ICMA), 0.1 microgram/L for two IRMAs, and 0.4 microgram/L for one RIA. All GH pulses with a peak ICMA value > 1 microgram/L were detected by each of the other methods. Overall, the correlation coefficient between the values obtained with all four assays exceeded 0.90. However, for GH concentrations < or = 0.25 microgram/L, acceptable concordance (r2 > or = 0.80) was reached only between the ICMA and one IRMA; between the ICMA and the RIA, concordance was acceptable only for GH concentrations > or = 10 micrograms/L. In the normal subjects, the percentage of undetectable values was 0% with the ICMA but 29% with one of the IRMAs; in obese subjects, the corresponding values were 12% and 38%. 相似文献
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The abrasion characteristics of Tencel fabrics were evaluated by Martindale abrasion and laundering, and the breakdown mechanism of fibers was surveyed by scanning electron microscopy. The fabric was subjected to pad‐dry‐cure treatment with two different types of modified dimethyloldihydroxyethylene urea resins (Reaktant DH and Reaktant FC). Although the degree of dry abrasion varied with different resins, the damage exhibited by individual fibers differed little from untreated to resin‐treated; the major mechanism of abrasion was through friction, and the mechanism of fiber failure was multiple splitting and transverse cracking. In untreated Tencel, the characteristic feature of wet abrasion was massive fibrillation, and in crosslinked fabrics, the wet abrasion mechanism was through fiber slippage and slicing action, although in the Reaktant FC‐treated fabric, the wet abrasion mechanism was more through slicing than through fiber splitting. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1391–1398, 2006 相似文献
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The introduction of Personal Computers has enabled Industrial Engineers to automate many aspects of their responsibilities, thus becoming significantly more productive. One aspect which clearly benefits from automation is the creation, implementation, and periodic maintenance of Pay-for-Performance Reward Systems. However, selecting the correct software package is not easy. Industrial Engineers currently have a variety of fully automated software packages to choose from which can range from $2,000 – $100,000. The initial cost alone may make it difficult to Justify for a small plant. Furthermore, if you have a variety of reward systems (Gainsharing - Small Group - One for One) finding a single program to handle all of them may be impossible.
This was a problem Norton Company faced five years ago. We are a fortune 500 company with manufacturing plants located throughout the world, using a variety of reward systems. To remain cost competitive in all aspects of our business, we had to find a way to reduce the on-going maintenance costs of our incentive systems.
Investigating alternatives uncovered a low cost, flexible solution to our problem. The use of off-the-shelf spreadsheet and data base software enabled us to fully automate all aspects of our reward systems. 相似文献
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Richard Zarr 《电子产品世界》2002,(24):52-52,58
系统设计师设计光纤通信系统时经常会遇到一个问题,那就是如何确保激光系统可在某一温度范围内保持其特性。若温度改变,激光系统的中心频率也会随着改变。为了确保频率保持稳定,新一代的固态激光模块都内置一个热电致冷器(Thermoelectric Cooler, TEC),以便将热能泵入模块或将热能释出,以调节温度。热电致冷器按照佩尔蒂埃效应(Peltier effect) 的原理运作。每当直流电流经热电致冷器时,热能便会由热电致冷器的一边传送至另一边,令热电致冷器的一边转“热”,另一边则转“冷”。若直流电被逆转,原先热的一边会转冷,冷的一边则会… 相似文献
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A concept is proposed for utilizing artificial neural networks to enhance the high-speed tracking accuracy of robotic manipulators. Tracking accuracy is a function of the controller's ability to compensate for disturbances produced by dynamical interactions between the links. A model-based control algorithm uses a nominal model of those dynamical interactions to reduce the disturbances. The problem is how to provide accurate dynamics information to the controller in the presence of payload uncertainty and modeling error. Neural network payload estimation uses a series of artificial neural networks to recognize the payload variation associated with a degradation in tracking performance. The network outputs are combined with a knowledge of nominal dynamics to produce a computationally efficient direct form of adaptive control. The concept is validated through experimentation and analysis on the first three links of a PUMA-560 manipulator. A multilayer perceptron architecture with two hidden layers is used. Integration of the principles of neural network pattern recognition and model-based control produces a tracking algorithm with enhanced robustness to incomplete dynamic information. Tracking efficacy and applicability to robust control algorithms are discussed. 相似文献
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Correction to Construction of Panoramic Image Mosaics with Global and Local Alignment 总被引:2,自引:1,他引:1
International Journal of Computer Vision - 相似文献