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81.
Fenglei Niu Haihua Zhao Per F. Peterson Joel Woodcock Robert E. Henry 《Nuclear Engineering and Design》2007,237(10):1025-1032
This experimental research investigates mixed convection and heat transfer augmentation by gaseous forced jets in a large enclosure, at conditions simulating those of passive containment cooling systems for Gen III+ passively safe reactors. The experiment is designed to measure the key parameters governing heat transfer augmentation by forced jets, and to investigate the effects of geometric factors, including the jet diameter, jet injection orientation, interior structures, and enclosure aspect ratio. The tests cover a variety of injection modes leading to flow configurations of interest for mixing and stratification phenomena in containments under accident conditions. Correlations for heat transfer augmentation by forced jets are developed and compared with experimental data. The characteristic recirculation speed inside the enclosure is introduced and analyzed. Steady stratified temperature distributions are compared with model simulations of the BMIX++ code. 相似文献
82.
Oil Spill Detection in Radarsat and Envisat SAR Images 总被引:8,自引:0,他引:8
Anne H. S. Solberg Camilla Brekke Per Ove Husoy 《Geoscience and Remote Sensing, IEEE Transactions on》2007,45(3):746-755
We present algorithms for automatic detection of oil spills in synthetic aperture radar (SAR) images. The algorithms consist of three main parts, namely: 1) detection of dark spots; 2) feature extraction from the dark spot candidates; and 3) classification of dark spots as oil spills or look-alikes. The algorithms have been trained on a large number of Radarsat and Envisat Advanced Synthetic Aperture Radar (ASAR) images. The performance of the algorithm is compared to manual and semiautomatic approaches in a benchmark study using 59 Radarsat and Envisat images. The algorithms can be considered to be a good alternative to manual inspection when large ocean areas are to be inspected 相似文献
83.
Dealing with conflicting and target-specific requirements is an important issue in multisensor and multitarget tracking. This paper aims to allocate sensing resources among various targets in reaction to individual information requests. The proposed approach is to introduce agents for every relevant target responsible for its tracking. Such agents are expected to bargain with each other for a division of resources. A bilateral negotiation model is established for resource allocation in two-target tracking. The applications of agent negotiation to target covariance tuning are illustrated together with simulation results presented. Moreover, we suggest a way of organizing simultaneous one-to-one negotiations, making our negotiation model still applicable in scenarios of tracking more than two targets. 相似文献
84.
Based on results from eigenspace and residual assignment a closed-form parameterization of all transfer function matrices obtainable by state feedback is given. 相似文献
85.
Per Brinch Hansen 《Software》1989,19(6):553-578
This paper defines a programming language for distributed processing called Joyce. Joyce is based on CSP and Pascal. A Joyce program defines concurrent agents which communicate through synchronous channels. The agents may be recursive. 相似文献
86.
Two coupling agents based on trichloro-s-triazine with different terminal unsaturated groups were synthesized in order to improve the bonding between cellulose fibers and an unsaturated polyester matrix. The products of the reactions between hydroxyl groups of cellulose and reactive species of coupling agents were analysed by Fourier-transform infrared spectroscopy (FTIR) and by elemental microanalyses. ESCA was used for surface characterization of treated fibers. The coupling agents were found to be concentrated on the fiber surface. Polymerization of styrene was carried out in the presence of treated fibers. That the unsaturated groups of the treated fibers were able to copolymrize with styrene was shown by FTIR. Further evidence of the presence of grafted polystyrene on the surfaces of the cellulose fibers was provided by ESCA measurements. 相似文献
87.
Although effective therapies for pathological gambling exist, their uptake is limited to 10% of the target population. To lower the barriers for help seeking, the authors tested an online alternative in a randomized trial (N = 66). The participants were pathological gamblers not presenting with severe comorbid depression. A wait-list control was compared with an 8-week Internet-based cognitive behavior therapy program with minimal therapist contact via e-mail and weekly telephone calls of less than 15 min. Average time spent on each participant, including phone conversations, e-mail, and administration, was 4 hr. The Internet-based intervention resulted in favorable changes in pathological gambling, anxiety, depression, and quality of life. Composite between-group effect size (Cohen's d) at posttreatment was 0.83. Follow-ups carried out in the treatment group at 6, 18, and 36 months indicated that treatment effects were sustained (ds = 2.58, 1.96, and 1.98). This evidence is in support of Internet-delivered treatment for pathological gamblers. However, it is not clear how effective the treatment is for more severely depressed individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
Observed parental interactive patterns in the presence (a triadic setting) and in the absence (a dyadic setting) of the spouse in 44 families with 16 female and 28 male early adolescents (approximately 13 yrs old). Findings indicate that in accordance with hypotheses, the presence of the father enhanced the quality of mother–son relations, whereas the presence of the mother reduced the quality of father–son relations. The presence of the spouse influenced the extent to which parents treated girls and boys differently: Mothers differentiated more between girls and boys in the presence of the spouse, whereas fathers differentiated more between girls and boys in the absence of the spouse. Relative to the dyad, parental role differentiation increased in the triad but only in families of boys. In demonstrating interdependencies among family relationships and the responsivity of parental behaviors to the interpersonal structure of interaction settings, the results support a systems model of family processes. Implications for the study of family relations and sex typing at early adolescence are discussed. (60 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
90.
We propose a new approach for catalyst development that combines different scientific disciplines: experimental design, surface
science, reaction kinetics and simulations with the objective of accelerating catalyst development. In this paper we present
a study of the possibilities of using small data sets in microkinetic modeling, and studies of the required precision of temperature
measurement. 相似文献