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101.
102.
Jeffrey J. Richardson Kurt A. Spies Steve Rigdon Sara YorkValerie Lieu Lloyd NackleyBetzaida Batella Garcia Rodney Cawston Daniel T. Schwartz 《Biomass & bioenergy》2011,35(8):3698-3707
The increasing demand for bioenergy in the United States necessitates detailed case studies of cost and supply to assess its feasibility. We have developed supply curves based on six feedstocks in five counties surrounding the Yakama Nation in central Washington using spatially explicit estimates of supply and transportation cost. The supply curves were used to examine a base case supply for a bioenergy plant, to analyze the effects of land ownership, and examine the impacts of uncertainty in parameters used to determine cost and supply. The results show that existing industries produce the cheapest supply of feedstock as a byproduct of their operations, while supplies harvested specifically for bioenergy are considerably more expensive. Fragmented land ownerships lead to the necessity of cooperation between owners and highlight the importance of a strong anchor supply close to the plant. Lastly, uncertainty in supply and cost parameters leads to larger ranges in available biomass, leading to reluctant investment in large plants. 相似文献
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Levine Brian; Dawson Deirdre; Boutet Isabelle; Schwartz Michael L.; Stuss Donald T. 《Canadian Metallurgical Quarterly》2000,14(4):491
Standard neuropsychological tests administered in a constrained and artificial laboratory environment are often insensitive to the real-life deficits faced by patients with traumatic brain injury (TBI). The Revised Strategy Application Test (R-SAT) creates an unstructured environment in the laboratory in which environmental cues and internal habits oppose the most efficient strategy, thus mimicking the real-life situations that are problematic for patients with TBI. In this study, R-SAT performance was related both to severity of TBI (i.e., depth of coma) sustained 2–3 years earlier and to quality of life outcome as assessed by the Sickness Impact Profile. This relationship held after accounting for variance attributable to TBI-related slowing and inattention. These findings support the validity of the R-SAT and suggest that behavioral correlates of quality of life outcome in TBI can be assessed in the laboratory with unstructured tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
Viviane Schwartz Hong Xie Harry M. Meyer III Steven H. Overbury Chengdu Liang 《Carbon》2011,(2):659-668
Graphitic mesoporous carbon was modified with phosphorous heteroatoms in order to tune the catalytic selectivity and to investigate the roles of different oxygen species for the oxidative dehydrogenation reaction of isobutane to isobutene. Small changes in the isobutane apparent activation energy are consistent with the notion that the phosphorous groups do not change the nature of the active sites but they interfere with the availability of the sites. Our results show that the improvement on selectivity is not proportional to the amount of phosphorous added. Small phosphorous content improved the selectivity by suppressing the combustion of isobutane. However, a higher amount of phosphorous groups lead to coverage of selective quinone sites and/or creation of active sites favorable to total oxidation. 相似文献
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FIRE: flexible intra-AS routing environment 总被引:2,自引:0,他引:2
Partridge C. Snoeren A.C. Strayer W.T. Schwartz B. Condell M. Castineyra I. 《Selected Areas in Communications, IEEE Journal on》2001,19(3):410-425
Current routing protocols are monolithic, specifying the algorithm used to construct forwarding tables, the metric used by the algorithm (generally some form of hop count), and the protocol used to distribute these metrics as an integrated package. The flexible intra-AS routing environment (FIRE) is a link-state, intradomain routing protocol that decouples these components. FIRE supports run-time-programmable algorithms and metrics over a secure link-state distribution protocol. By allowing the network operator to dynamically reprogram both the properties being advertised and the routing algorithms used to construct forwarding tables, FIRE enables the development and deployment of novel routing algorithms without the need for a new protocol to distribute state. FIRE supports multiple concurrent routing algorithms and metrics, each constructing separate forwarding tables. By using operator-specified packet filters, separate classes of traffic may be routed using completely different routing algorithms, all supported by a single routing protocol. This paper presents an overview of FIRE, focusing particularly on FIRE's novel aspects with respect to traditional routing protocols. We consider deploying several current unicast and multicast routing algorithms in FIRE, and describe our Java-based implementation 相似文献
108.
Investigated the stability of Minnesota Multiphasic Personality Inventory (MMPI) code types. Ss were 405 psychiatric patients (mean age 37 yrs) who had completed 2 valid MMPIs and some of whom had been rated twice on the Brief Psychiatric Rating Scale. Test–retest agreements for high-point, low-point, and 2-point codes were 42.72%, 43.95%, and 27.65%, respectively. Code types were somewhat more stable when scales in the codes had more extreme scores initially and when scores on the scales in the codes were considerably different from other scales in the profile. When MMPIs were classified as neurotic, psychotic, or characterological according to 2-point codes, many of the 2-point codes that changed from test to retest remained within the same diagnostic categories. For a subsample of 72 Ss, behavioral ratings of psychosis were compared with stability and change in 2-point code types. Results suggest that at least some changes in code types over time may be associated with meaningful behavioral changes. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
Schwartz Gary S.; Friedlander Myrna L.; Tedeschi James T. 《Canadian Metallurgical Quarterly》1986,33(1):90
On the basis of an impression-management view of the counseling interaction, the effects of clients' initial self-presentations on counselors' impressions were investigated. It was predicted that a client offering personal attributional explanations (claiming responsibility for his/her problematic behavior) would be seen in a more favorable light than would one who attributed his/her predicament to others or to the situation. It was also expected that the client who expressed an intrinsic (self-improvement) reason for seeking help would make a better impression than would one who offered an extrinsic (nontherapeutic) reason. Ratings by 77 graduate psychology or social work students of stimulus tapes that manipulated these variables supported the hypotheses. The client who expressed personal attributions was viewed as more motivated and attractive than was the client who made situational attributions. When the reason for seeking help was intrinsic, Ss perceived the client to be more motivated and as having a better prognosis for change. There were, however, no uniquely significant effects on specific outcome expectancies or on judgments of problem severity. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Schwartz M. Bruck J. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2008,54(5):2179-2195
We address the well-known problem of determining the capacity of constrained coding systems. While the one-dimensional case is well understood to the extent that there are techniques for rigorously deriving the exact capacity, in contrast, computing the exact capacity of a two-dimensional constrained coding system is still an elusive research challenge. The only known exception in the two-dimensional case is an exact (however, not rigorous) solution to the -run-length limited (RLL) system on the hexagonal lattice. Furthermore, only exponential-time algorithms are known for the related problem of counting the exact number of constrained two-dimensional information arrays. We present the first known rigorous technique that yields an exact capacity of a two-dimensional constrained coding system. In addition, we devise an efficient (polynomial time) algorithm for counting the exact number of constrained arrays of any given size. Our approach is a composition of a number of ideas and techniques: describing the capacity problem as a solution to a counting problem in networks of relations, graph-theoretic tools originally developed in the field of statistical mechanics, techniques for efficiently simulating quantum circuits, as well as ideas from the theory related to the spectral distribution of Toeplitz matrices. Using our technique, we derive a closed-form solution to the capacity related to the Path-Cover constraint in a two-dimensional triangular array (the resulting calculated capacity is ). Path-Cover is a generalization of the well known one-dimensional -RLL constraint for which the capacity is known to be . 相似文献