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71.
A bibliography is presented on the subject of power system analysis from a probabilistic point of view. Comprising 269 references, this bibliography focuses on probabilistic loadflow, probabilistic short circuit, and probabilistic dynamic analysis (probabilistic security). An additional section covering general topics (analysis and engineering) and a list of previous bibliographies are also presented.<>  相似文献   
72.
73.
This longitudinal study predicted marital outcome from communication skills gained from participation in the Prevention and Relationship Enhancement Program (PREP; H. J. Markman, S. L. Blumberg & S. M. Stanley, 1989; Stanley et al., 2001) by 39 women and 38 men. Results were in the expected direction for men but not for women. Men's pre- to posttest decrease in negative communication and increase in positive communication predicted decreased risk of marital distress onset in men. Women's pre- to posttest increase in positive communication, which was related to self-reported avoidance of problem solving, predicted an increased risk of male and female distress onset. Couples with men relatively high on premarital risk factors demonstrated a greater benefit from men's positive communication skills acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
74.
Modern Internet and multimedia techniques enable experiments with remote hardware. This way engineering students can gather practical experience even in areas where their own university does not have the related equipment in place. The focus of this paper is on an experiment to develop a motor controller for a remote mobile robot. Implementation details of such an experiment are addressed with emphasis placed on the subject of tuning a PID controller for steering and speed adaptation of a rover. The complete experiment is conceived as a self‐explaining learning unit on the web. The learning unit comprises material on theory, exercises to provide feedback to the student about his learning progress, simulations to study motor control effects, and finally the experiment with remote robot hardware. This paper presents software techniques to realize a robust system implementation, the educational considerations necessary to present the experiment material properly for the tele‐education context, and experiences obtained during the use of this remote experiment in previously taught classes. © 2005 Wiley Periodicals, Inc.  相似文献   
75.
The authors present new results on extended electrical tuning, fast spatial switching, and optically controlled wavelength conversion characteristics for the recently developed InP-based Y-laser structure. The devices have a 80 nm thick bulk InGaAsP active layer and are completely grown by metalorganic vapor phase epitaxy. The facets at both ends of the chip are as-cleaved without antireflective coating. The addressable range for electrically controlled wavelength switching was extended to the record value of 28 nm. When operated as a lossless 1:2 optical space switch, fiber-to-fiber gain >0 dB, extinction ratio >50 dB and high speed operation up to 1 Gb/s were shown. Optically triggered tunable wavelength conversion including dynamic operation was also demonstrated  相似文献   
76.
The use of spread-spectrum techniques to achieve more efficient utilization of available frequency spectra is examined. The two main spread-spectrum techniques, direct sequence and frequency hopping, are explained. In frequency hopping, the transmitter repeatedly changes (hops) the carrier frequency from one frequency to another. Direct-sequence transmission spreads the spectrum not by periodically changing the frequency but by modulating the original (information) baseband signal with a very wide-baseband digital signal. The wideband modulating signal's amplitude changes continually between two states, high and low, arbitrarily called +1 and -1, respectively, with the sequence of highs and lows being pseudorandom. Applying spread spectrum to code-division multiaccess (CDMA) communication, in which each user is assigned an identification code (a distinct sequence of frequencies for frequency hopping or +1 s and -1 s for direct-sequence modulation) is discussed. The use of CDMA for cellular radio, where it promises a capacity of over 1000 users per cell, by the authors' calculations, is considered. The potential of spread spectrum for relieving spectrum congestion is addressed  相似文献   
77.
This paper reviews the work carried out in the ACTS KEOPS (Keys to Optical Packet Switching) project, describing the results obtained to date. The main objective of the project is the definition, development, and assessment of optical packet switching and routing networks, capable of providing transparency to the payload bit rate, using optical packets of fixed duration and low bit rate headers in order to enable easier processing at the network/node interfaces. The feasibility of the KEOPS concept is assessed by modeling, laboratory experiments, and testbed implementation of optical packet switching nodes and network/node interfacing blocks, including a fully equipped demonstrator. The demonstration relies on advanced optoelectronic components, developed within the project, which are described  相似文献   
78.
DVD检测概要     
DVD光盘生产相对于传统的CD生产而言对品质控制的依赖更加紧密,丰富的过程控制经验可以使生产合格率不断增加,离线检测和在线检测的合理配合对于整个生产过程是十分重要的,这是一个获得好的收益率的前提。  相似文献   
79.
Bogdan AG  Boss ES 《Applied optics》2011,50(21):3758-3772
Seawater inherent optical properties (IOPs) are key parameters in a wide range of applications in environmental studies and oceanographic research. In particular, the absorption coefficient (a) is the typical IOP used to obtain the concentration of chlorophyll-a in the water-a critical parameter in biological oceanography studies and the backscattering coefficient (b(b)) is used as a measure of turbidity. In this study, we test a novel instrument concept designed to obtain both the absorption and backscattering coefficients. The instrument would emit a collimated monochromatic light beam into the water retrieving the backscattered light intensity as a function of distance from the center of illumination. We use Monte Carlo modeling of light propagation to create an inversion algorithm that translates the signal from such an instrument into values of a and b(b). Our results, based on simulations spanning the bulk of natural values of seawater IOP combinations, indicate that a 6.2 cm diameter instrument with a radial resolution of 1 cm would be capable of predicting b(b) within less than 13.4% relative difference and a within less than 57% relative difference (for 90% of the inverted a values, the relative errors fall below 29.7%). Additionally, these errors could be further reduced by constraining the inversion algorithm with information from concurrent measurements of other IOPs. Such a compact and relatively simple device could have multiple applications for in situ optical measurements, including a and b(b) retrievals from instrumentation mounted on autonomous underwater vehicles. Furthermore, the same methodology could possibly be used for an out-of-water sensor.  相似文献   
80.
Non‐invasive imaging holds significant potential for implementation in tissue engineering. It can be used to monitor the localization and function of tissue‐engineered implants, as well as their resorption and remodelling. Thus far, however, the vast majority of effort in this area of research have focused on the use of ultrasmall super‐paramagnetic iron oxide (USPIO) nanoparticle‐labeled cells, colonizing the scaffolds, to indirectly image the implant material. Reasoning that directly labeling scaffold materials might be more beneficial (enabling imaging also in the case of non‐cellularized implants), more informative (enabling the non‐invasive visualization and quantification of scaffold degradation), and easier to translate into the clinic (cell‐free materials are less complex from a regulatory point‐of‐view), three different types of USPIO nanoparticles are prepared and incorporated both passively and actively (via chemical conjugation; during collagen crosslinking) into collagen‐based scaffold materials. The amount of USPIO incorporated into the scaffolds is optimized, and correlated with MR signal intensity, showing that the labeled scaffolds are highly biocompatible, and that scaffold degradation can be visualized using MRI. This provides an initial proof‐of‐principle for the in vivo visualization of the scaffolds. Consequently, USPIO‐labeled scaffold materials seem to be highly suitable for image‐guided tissue engineering applications.  相似文献   
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