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991.
The paper is a review of recent developments in light sources for filming and projection in both the amateur and the professional fields. Three recent major technical advances are described, namely: Halogen Lamps, Sealed Beam Lamps and Dichroic coating, as applied to lamps, are dealt with in some detail. The most important lamp designs for each particular application are also reviewed 相似文献
992.
993.
Susan M. Fluegel Terry D. Shultz Joseph R. Powers Stephanie Clark Celestina Barbosa-Leiker Bruce R. Wright Timothy S. Freson Heidi A. Fluegel Jonathan D. Minch Lance K. Schwarzkopf Ashley J. Miller Michael M. Di Filippo 《International Dairy Journal》2010,20(11):753-760
Whey protein beverages reduced blood pressure in young men and women in a six week controlled intervention. There were no differences in systolic blood pressure (SBP), diastolic blood pressure (DBP), or mean arterial pressure (MAP) observed between groups consuming 28 g per day of either hydrolyzed or non-hydrolyzed whey protein in a beverage. However, in young adults with elevated DBP and SBP, whey beverage consumption significantly decreased SBP, DBP, and MAP by 8.0, 8.6, and 6.4 mm Hg, respectively (P ≤ 0.001 for all comparisons). In subjects with elevated SBP only, SBP significantly decreased by 3.8 mm Hg (P ≤ 0.04) after the whey beverage intervention. Subjects with normal blood pressure had no change in SBP, DBP, and MAP. Whey beverages also significantly decreased total and low-density lipoprotein cholesterol concentrations (P ≤ 0.001 and 0.05, respectively). Whey protein beverages may be useful for the dietary treatment of prehypertension and/or stage 1 hypertension. 相似文献
994.
Suitable positioning of temperature probes improves the accuracy of thermal-diffusivity measurements in thermo-optical tests. The optimal positions depend on the unknown diffusivity, making the positions unknown a priori. One solution is to measure the temperature field and choose the optimal positions after the experiment. D-optimality is used here to choose the best positions for temperature measurement to determine the principal components of thermal diffusivity for transversely isotropic materials in a flash-type experiment. Two D-optimality parameters are examined: one uses all available information; the other neglects nuisance parameters. The slab specimens are heated over a central region while temperatures are measured on the opposite face. Increasing the duration of the heating pulse provides more information, within the limit of the imposed boundary conditions. Experiments using a metal plate showed that measurements made near the optimal positions improve the accuracy of the estimated diffusivity. These results support using IR thermography to provide flexibility in positioning measurements. This method of optimization shows promise in optimizing measurement of specimens having transverse isotropy. 相似文献
995.
997.
A neuro-fuzzy approach for robot system safety 总被引:1,自引:0,他引:1
Zurada J. Wright A.L. Graham J.H. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2001,31(1):49-64
Robot safety is a critical and largely unsolved problem involving the interaction of man and machine. The paper presents a new approach to robot safety which uses an integrated sensing architecture for monitoring the robot workspace, and a new detection and decision logic for regulating the safe operation of the robot. Sensory information is fused through a trained neural network to produce a map of the hazards. Using this combined map, and information about the robot's current position and velocity, a set of fuzzy logic rules has been implemented to regulate robot activity. Simulation results presented in the paper indicate that this method is both effective in detection of potentially hazardous situations and computationally feasible 相似文献
998.
999.
C. Wright E. J. Davenport D. Kan-King-Yu D. Jefferies R. Cubberley S. P. D. Lalljie 《Food Additives & Contaminants》2005,22(8):716-725
Bleaching earth (dried, powdered, bentonite-montmorillonite clay) is commonly used as a processing aid in edible oil refinement. Used bleaching earth may be incorporated into animal feed indirectly, for example because it is included into seed meal, or directly (e.g., as a binding agent). Control must be demonstrated to ensure that the levels of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in feed ingredients do not infringe European Community regulations. The low legislative action level assigned is analytically challenging and may be at or below the limits of quantification achievable by many laboratories. A statistical comparison (following the IUPAC/ISO/AOAC protocol) was made of analyses of PCDDs and PCDFs in selected bleaching earth samples by laboratories from Europe and the USA to assess the comparability of data. Of 19 sets of results submitted by laboratories for replicate samples, 11 demonstrated acceptable agreement. 相似文献
1000.
Andy Turudic 《电子设计应用》2005,(9):24-24,26
在整个行业降低芯片引脚数量、减少EMI及消除5V容限信令的呼声中,SATA(串行ATA)磁盘驱动器接口应用最近在企业及台式机系统中明显增多。SATA接口在硬盘驱动器、DVD/CDR播放器/刻录机、主板和独立磁盘冗余陈列(RAID)控制器中的应用给大容量存储设备的传统连接及使用方式带来了挑 相似文献