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961.
Seskar Ivan Pedersen Klaus I. Kolding Troels E. Holtzman Jack M. 《Wireless Networks》1998,4(6):447-452
This paper addresses the practical implementation of Successive Interference Cancellation (SIC) for DS/CDMA systems. The practical
aspects of such an implementation are discussed and a convenient pipelined architecture is presented. An important aspect
is the integration of power control (PC) and interference cancellation which has synergistic effects of optimizing the SIC,
reducing intercell interference, and facilitating the implementation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
962.
This note responds to the arguments and evidence adduced by Kagan (1987) in his reply to the Block, Gjerde, and Block (1986) study questioning the validity of the Matching Familiar Figures Test (MFFT) as a measure of "reflection–impulsivity." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
963.
964.
It has been the goal of this article to provide the reader with a brief background of fMRI, a basic understanding of the techniques of fMRI, and, more importantly, the potential for clinical and experimental studies using fMRI. In contrast to the limited number of installed PET and MEG units, the large installed base of MR imaging scanners (over 1000 installed at least at 1.5 T in the United States) makes fMRI potentially widely available. Initial studies (both clinical and experimental) have been validated and are reproducible in mapping the sensorimotor and visual cortices. The areas of language lateralization and memory are still preliminary at best. As methods to reduce the effects of head motion (due to both bulk head motion and physiologically induced motion) arise, the reliability of fMRI should improve, allowing for more definitive identification of task activation. 相似文献
965.
Self-with-other processing and construction play an important role in human adjustment, development, and change. This idea is critical for an adequate understanding of psychotherapy and psychotherapeutic change. A theory of psychotherapeutic change that combines elements of both social constructionist and cognitive constructivist thought is presented briefly. After reviewing salient examples of both forms of thought as these have manifested in theorizing about psychotherapeutic change, a sampling of original empirical demonstrations is offered in support of the theory. Psychotherapeutic change is described as a process of appropriation and practical application through which clients internalize therapeutic conversations and activities, which they then use as psychological tools to restructure personal theories, experiences, and actions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
966.
John S. Sampalis Hala Tamim Andreas Nikolis André Lavoie Jack I. Williams 《Accident; analysis and prevention》1996,28(6):675-684
Physiological measures of injury are used as triage tools to identify patients that require treatment in trauma centres. The Pre-Hospital Index (PHI) is based on systolic blood pressure, pulse, respiratory rate, (level of) consciousness, and presence of penetrating injury. The present study evaluated the validity and internal consistency of the PHI. The study was based on 628 patients assessed by physicians at the scene. Mean age was 38.7 years (SD = 24.8), and 65% were male. Motor vehicle collisions caused the injury for 45%. The majority had head/neck (56%) and extremity (45%) injuries. Mean PHI was 4.62 (SD = 5.77), 40% had a PHI of zero, 6% between 1 and 3, 32% between 4 and 7, and 21% greater than 7. The associations between PHI and rates of hospital admission, surgery, ICU treatment, mortality, duration of hospitalization, and length of ICU stay were significant (p < 0.001). A total of 260 (41.4%) patients had major trauma requiring treatment at a trauma centre. A PHI> 3 had 83% sensitivity and 67% specificity for identifying these patients. Internal consistency of the PHI variables was above the acceptable limits. This study has shown that the PHI is a valid and reliable physiological measure of injury severity and field triage tool. 相似文献
967.
Jack Chen Zhifang Fan Jun Zou Jonathan Engel Chang Liu 《Canadian Metallurgical Quarterly》2003,16(2):85-97
We discuss two types of micromachined flow sensors realized by using novel microfabrication processes—a hot-wire anemometer (based on thermal transfer) and a biologically inspired flow sensor (based on momentum transfer). Both sensors are enabled by a new, efficient three-dimensional assembly technique called the plastic deformation magnetic assembly method. The sensors can be packaged in high-density, two-dimensional arrays efficiently, with each sensor node capable of performing two-component or three-component flow sensing. We first discuss the development of new hot-wire anemometers (HWA). The HWA uses a thermal element (hot wire) that is made of Pt/Ni/Pt film with a measured temperature coefficient of resistance of 2,700 ppm/°C. The thermal element is elevated out of plane by using support beams made of polyimide, a polymer material. Both steady-state and transient characteristics of the sensor have been experimentally obtained. The second type of flow sensor is based on momentum transfer principles and inspired by fish lateral line sensors. Each sensor consists of a vertical cilium attached to a horizontal cantilever. Fluid flow imparts moment on the vertical cilium, and causes the horizontal cantilever to bend. The fabrication process and preliminary measurement data are presented. 相似文献
968.
The Thematic Mapper (TM) is a second-generation Earth resources sensor built by Hughes Aircraft Company for NASA for the LANDSAT series of spacecraft. The TM was placed in orbit aboard the LANDSAT-D spacecraft in July of 1982. Its predecessor, the Multispectral Scanner (MSS) has flown on LANDSAT's 1 through 3 and accompanies the TM on LANDSAT-D. The need for improved performance was recognized prior to the launch of the first MSS on LANDSAT-1 in 1972. The performance specifications for the TM were formulated to produce performance improvements in the next generation sensor. This paper will provide an overview of TM and will briefly discuss the LANDSAT-D mission and orbit, TM design, instrument performance, and program status. 相似文献
969.
Development and application of a fire station placement model 总被引:1,自引:0,他引:1
This paper describes the development and application of a fire station placement model. The model is formulated as a mathematical programming model which locates p sites out of m candidate sites such that some function of the travel times of the first and second arriving fire units is maximized subject to several constraints. Among these constraints are limitations in the maximum allowable travel time to points in a region, requirements that certain sites be included or excluded, and a specification that a given number of existing sites be included.The model uses as an objective function a utility function based on the subjective preferences of fire department officials to travel times of the first and second arriving fire units. A modification of the Teitz and Bart node substitution heuristic is used to find the solution to the model.The model is applied to fire station locational decisions in Albany, NY. The model was run a number of times to provide insights into how some strategic decisions might be made.
Reference: Jack M. Reilly and Pitu B. Mirchandani, Development and Application of a Fire Station Placement Model,Fire Technology, Vol. 21, No. 3, August 1985, p. 181. 相似文献
970.
Jack R Wallin Neil W Widstrom Bruce A Fortnum 《Journal of the science of food and agriculture》1991,54(2):235-238
Maize (Zea mays L) germplasm is needed with resistance to infection by Aspergillus flavus and/or subsequent contamination by aflatoxin B1 (AFB1). A select group of maize populations were evaluated for their resistance to AFB1 contamination at three locations. Four populations (Ibadan B and three others derived from crosses between Corn Belt inbreds and diploid perennial teosinte. Zea diploperennis) were compared with a susceptible hybrid check in a randomised complete block experiment with 10 replicates in Georgia, Missouri and South Carolina for two years. Ears were not inoculated, and naturally occurring concentrations of AFB1 in harvested grain were analysed for population differences. Ibadan B and Mo2 W × Z diploperennis had significantly lower average amounts of AFB1, 19 μg kg?1 and 18 μg kg?1, respectively, than other test entries. Backcrossing to susceptible Corn Belt inbreds produced populations as susceptible as the check when resistance was measured as the concentrations of AFB1 in the grain. The consistency and significance of low AFB1 concentrations for Ibadan B and Mo20W × Z diploperennis suggest that these may be useful sources of resistance. 相似文献