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961.
Points out that the creation and use of rituals is found in various aspects of the human experience. In strategic psychotherapy, rites of separation are used to aid clients in taking leave of the past. These rituals have a common structure, but their form and content vary according to the personality, needs, and experiences of clients. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
962.
This paper presents a method for extracting, in the digital domain, the main characteristic parameters of an analog sine-wave signal. It is based on a double-modulation, square-wave and sigma-delta, together with a simple Digital Processing Algorithm. It leads to an efficient and robust approach very suitable for BIST applications. In this line, some considerations for on-chip implementation are addressed together with simulation results that validate the feasibility of the proposed approach.Diego Vázquez was born in El Coronil, Sevilla, Spain, in 1966. He received the Licenciado en Física degree in 1989 and the Doctor en Ciencias Físicas degree in 1995, both from the University of Sevilla, Spain. Since 1990, he has been with the Departamento de Electrónica y Electromagnetismo, University of Sevilla, where he is a Associate Professor, and also with the Instituto de Microelectrónica de Sevilla, Centro Nacional de Microelectrónica (IMSE-CNM-CSIC), Sevilla, Spain. He has published about 100 papers in international journals, books and major conferences. In 1992 he won the Best Paper Award of the 10th IEEE VLSI Test Symposium. His research interests are in the fields of design, fault tolerance, test, and design for testability of analog and mixed-signal circuits.Gloria Huertas was born in Sevilla, Spain, in 1974. She received the Licenciado en Física degree in 1997 and the Ph.D. in 2004, both from the University of Sevilla, Spain. Since then, she has been with the Departamento de Electrónica y Electromagnetismo, University of Sevilla, where she is Assistant Professor, and also with the Instituto de Microelectrónica de Sevilla, Centro Nacional de Microelectrónica (IMSE-CNM-CSIC), Sevilla, Spain. Her research focuses on designing electronic mixed-signal circuits and systems including techniques for testability.África Luque was born in Zamora (Spain) in 1977. She received the Licenciado en Física degree in 2000 from the University of Sevilla, Sevilla, Spain. She is with the Departamento de Electrónica y Electromagnetismo, University of Sevilla, and also with the Instituto de Microelectrónica de Sevilla, Centro Nacional de Microelectrónica (IMSE-CNM-CSIC), Sevilla, Spain, where she is currently pursuing the Ph.D. degree. Her research focuses on the design and test of mixed-signal circuits including Silicon-On-Insulator technologies.Manuel J. Barragan was born in Sevilla, Spain, in 1980. He received the Licenciado en Física degree in 2003 from the University of Sevilla, Sevilla, Spain. He is currently pursuing the Ph.D. degree from the Instituto de Microelectrónica de Sevilla (IMSE, CNM) on the topics of test and design for testability of analog and mixed-signal circuits.Gildas Leger was born in St. Brieuc, Côtes dArmor, France, in 1976. He received the Ingénieur en Physique degree in 1999 from the National Institute of Applied Sciences (INSA) of Rennes, France.He is currently pursuing the Ph.D. degree from the Instituto de Microelectrónica de Sevilla (IMSE, CNM). His research focuses on designing electronic mixed-signal circuits and systems including techniques for testability, specially in the domain of analog to digital conversion.Adoración Rueda joined the Department of Electronics and Electromagnetism at the University of Seville in 1976 as Assistant Professor, and obtained the Ph.D. degree in 1982. From 1984 to 1996 she was Associate Professor in that Department, where now holds the position of Full Professor in Electronics. In 1989 she became researcher at the Department of Analog Design of the National Microelectronics Center (CNM), now Institute of Microelectronics at Seville (IMSE).She has participated in several research projects financed by the Spanish CICYT and by different programs of the European Community. She has published about 135 papers in international journals, books and major conferences. In 1992 she won the Best Paper Award of the 10th IEEE VLSI Test Symposium. Her research interests are currently focused on the topics of Design and Test of Analog and Mixed-signal Circuits, Behavioral Modeling of Mixed-signal Circuits, and development of CAD tools.Jose Luis Huertas received the Licenciado en Física degree nd the Doctor en Ciencias Físicas degrees in 1969 and 1973, respectively, both from the University of Sevilla, Spain.From 1970 to 1971, he was with the Philips International Institute, Eindhoven, The Netherlands, as a postgraduate student. Since 1971, he has been with the Departamento de Electrónica y Electromagnetismo, University of Sevilla, Spain, where he is a Full Professor. He is also the Director of the Instituto de Microelectrónica de Sevilla, Centro Nacional de Microelectrónica de Sevilla, Seville, Spain. His current interests include the design and testing of analog/digital integrated circuits, computer-aided IC analysis and design, fuzzy logic, nonlinear microelectronics, and neural networks.  相似文献   
963.
Irreversible adsorbed bismuth can be used to determine the fraction of (111) domains on a given platinum sample. On Pt(111) electrodes, the surface redox process of adsorbed bismuth takes place at 0.63 V in a well-defined peak. The behavior of this redox process on the Pt(111) vicinal surfaces indicates that the bismuth atoms involved in the redox process are only those deposited on the (111) terrace sites and that the charge under the peak at 0.63 V is directly proportional to the number of sites on (111) ordered domains (terraces). The good linear relationship obtained between the charge for the bismuth redox process and the number of (111) terrace sites on the vicinal surfaces allows construction of a calibration curve. This calibration curve has been used to directly estimate the amount of (111) ordered domain terrace sites on polycrystalline platinum samples with different surface ordered domains. The results agree with what we would expect from our knowledge of these surfaces.  相似文献   
964.
Methods for Operations Planning in Airport Decision Support Systems   总被引:2,自引:0,他引:2  
Simulation and decision support tools can help airport ground controllers to improve surface operations and safety, leading to enhancements in the process of traffic flow management. In this paper, two planning approaches for automatically finding the best routes and sequences for demanded operations are proposed and analyzed. These approaches are integrated into a general decision support system architecture. The problem addressed is the global management of departure operations, moving aircraft along airport taxiways between gate positions and runways. Two global optimization approaches have been developed together with a suitable problem representation: a modified time-space flow algorithm and a genetic algorithm, both aimed at minimizing the total ground delay. The capability and performance of these planning techniques have been illustrated on simulated samples of ground operations at Madrid Barajas International Airport.This work was funded by CICYT (TIC2002-04491-C02-02) and CAM (07T/0034/2003 1)  相似文献   
965.
The use of two additional reservoirs to accommodate the electrodes of the power source is proposed to improve the stability of the running electrolyte in capillary electrophoresis. The basic idea is to use salt bridges to connect those reservoirs to the ones containing the capillary ends. Although simple, there are several issues that can be considered in the design and implementation of such system in order to prevent undesired transference of material between the electrolysis and the main reservoirs. The use of a sealed electrolysis reservoir without a gas phase, the use of materials that ensure volume stability, and the use of bridges as long as possible are three basic directions. A compromise is involved in the dimensions of the sectional area of the bridge, because a small area diminishes the amount of a species transferred by diffusion but leads to an undesirable increase of the electrical field during the electrophoretic running. Thus, a bridge composed of a main wide-bore tube connected to a small-bore capillary seems to give the best performance for practical use. A simple electrolysis-separated system was adapted to a preexisting capillary electrophoresis system, and its performance was evaluated with a mixture of tartaric, malic, and succinic acids that was separated in sodium benzoate solution (pH 5.5) using the original equipment and the modified one. Due to the water electrolysis and the small buffering capacity of the electrolyte, there was a significant pH change and consequently changes in the effective mobilities of the analytes and loss of resolution after a few runs using the original equipment. Using the electrolysis-separated system, no significant change in the migration time and resolution was observed even after 15 runs. Besides the freedom to prepare running electrolytes with electroactive species or unbuffered solution, high throughput and the use of small reservoirs, such as the ones used in microfluidic devices, are the main advantages of the system.  相似文献   
966.
To achieve the wavefront phase-recovery stage of an adaptive-optics loop computed in real time for 32 x 32 or a greater number of subpupils in a Shack-Hartmann sensor, we present here, for what is to our knowledge the first time, preliminary results that we obtained by using innovative techniques: graphical processing units (GPUs) and field-programmable gate arrays (FPGAs). We describe the stream-computing paradigm of the GPU and adapt a zonal algorithm to take advantage of the parallel computational power of the GPU. We also present preliminary results we obtained by use of FPGAs on the same algorithm. GPUs have proved to be a promising technique, but FPGAs are already a feasible solution to adaptive-optics real-time requirements, even for a large number of subpupils.  相似文献   
967.
We experimentally study the effect of ionizing radiation on the properties of long-period gratings fabricated in two pure-silica-core fibers with the arc-discharge technique. It is observed that the spectra of the gratings remain almost unchanged after being subjected to doses in excess of 0.5 MGy. The results also show that the gratings' temperature and strain sensitivities are not affected by gamma radiation.  相似文献   
968.
In this paper, a multiservice transmission scheme which joints voice, video, interactive game and signaling is evaluated for the dedicated channel of the Universal Mobile Telecommunications System. The transmission rate for each service is determined by means of an adaptive transport format selection. In the UMTS standard, this selection is based on power allocation provided by radio resource controller, trying to match the Eb/No requirements of the individual services. An appropriate selection of the individual rates of each multiplexed service, taking into account its particular QoS requirements, will provide a more efficient resource management than the transmission only restricted to power allocation. For this purpose, we propose and evaluate a new selection strategy based on buffer occupation, delay requirements and target bit rate keeping power constraints that intends to improve the basic operation trying to minimize the impact of the whole network. Video and game services are multiplexed in upper layers (logical channels) sharing a common transmission rate (transport channel). In this paper, it is proposed a new strategy to share the transmission rate set for this transport channel between both services taking into account their particular requirements. Results show that considering delay constraints provides a more balanced performance of the multiplexed services.  相似文献   
969.
970.
We develop a semiclassical theory to explain the rapid ripple fluctuations in the extinction efficiency of light scattering by a transparent prolate spheroid. The theory is based on uniform asymptotic expansion of spheroidal radial functions. We have calculated the extinction efficiency for normal and oblique incidence. Our results suggest that the excitation of resonant electromagnetic modes inside a spheroidal particle is an important factor in the ripple structure. To verify this assumption and based on a Breit-Wigner formula, we develop a method to fit the peaks that appear in the spheroid's extinction cross section when some scattering parameters vary. In other words, our calculations suggest that narrow resonances are related to ripple fluctuations, whereas broad resonances contribute to extinction cross-sectional background.  相似文献   
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