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61.
Interim, centralized, engineered (dry cask) storage facilities for USA light water power reactor spent nuclear fuel (SNF) should be implemented to complement and to offer much needed flexibility while the Nuclear Regulatory Commission is funded to complete its evaluation of the Yucca Mountain License and to subject it to public hearings. The interim sites should use the credo reproduced in Table 1 [Bunn, M., 2001. Interim Storage of Spent Nuclear Fuel. Harvard University and University of Tokyo] and involve both the industry and government. The sites will help settle the 50 pending lawsuits against the government and the $11 billion of potential additional liabilities for SNF delay damages if Yucca Mountain does not being operation in 2020 [DOE, 2008a. Report to Congress on the Demonstration of the Interim Storage of Spent Nuclear Fuel from Decommissioned Nuclear Power Stations (December)].Under the developing consensus to proceed with closed fuel cycles, it will be necessary to develop SNF separation facilities with stringent requirements upon separation processes and upon generation of only highly resistant waste forms. The location of such facilities at the interim storage sites would offer great benefits to those sites and assure their long term viability by returning them to their original status.The switch from once-through to closed fuel cycle will require extensive time and development work as illustrated in “The Path to Sustainable Nuclear Energy” [DOE, 2005. The Path to Sustainable Nuclear Energy. Basic and Applied Research Opportunities for Advanced Fuel Cycles. DOE (September)]. A carefully crafted long term program, funded for at least 5 years, managed by a strong joint government–industry team, and subjected to regular independent reviews should be considered to assure the program stability and success.The new uncertainty about Yucca Mountain role raises two key issues: (a) what to do with the weapons and other high level government wastes committed to be moved to Yucca Mountain by specified dates? And (b) can the $13.6 billion invested at Yucca Mountain be salvaged if the NRC approves the license submittal and the opposition relents after contentious hearings? Or will it take contingent actions, or, a switch to a partial closed fuel cycle with its reduced risks and earlier timing of their peak risk value? Only time will tell if any of these alternates will be acceptable but, they all reinforce the need for interim storage for commercial SNF.If the decision is to go to a new repository one wonders whether the time has not come to change the safety evaluation process for geological repositories by characterizing two to three sites and subjecting them to an arbitrary release of the fission products in the HLW to be stored and considering the forms of some of the HLW to reduce their peak risks. It would allow the proper choice to be made among the selected sites and to have a basis for convincing the local committee to accept the repository location. It may even decide whether the CONFU fuel assembly [MIT, 2006. Implications of alternative strategies for transition to sustainable fuel cycles. Nucl. Sci. Eng., 154 (September)] for pressurized water reactors can be accommodated in a once-through fuel cycle as suggested by Levy [Levy, S., 2008. Yucca backup plan. Nucl. Eng. Int., 24–28]. A similar configuration is possible in boiling water reactors. 相似文献
62.
The aim of this study was to explore the long-term effects of affect-focused body psychotherapy (ABP) for patients with generalized anxiety disorder (GAD). A group of 61 consecutive patients, 21–55 years old, were randomized to ABP and psychiatric treatment as usual (TAU). The patients were assessed before treatment and followed up 1 and 2 years after inclusion. The ABP patients received one session of treatment per week during 1 year. Three self-report questionnaires were administered; Symptom Checklist—90, Beck Anxiety Inventory, and the WHO (Ten) Well-Being Index. In both groups, there was a significant improvement. On termination, the ABP group had improved significantly more on the SCL-90 Global Symptom Index than the TAU group, whereas the differences were short of significance on the other two scales. The integration of bodily techniques with a focus on affects in a psychodynamically informed treatment seems to be a viable treatment alternative for patients with GAD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
63.
This reply to the commentary by E. Staub and L. A. Pearlman (2009) revisits the field experimental results of E. L. Paluck (2009). It introduces further evidence and theoretical elaboration supporting Paluck's conclusion that exposure to a reconciliation-themed radio soap opera changed perceptions of social norms and behaviors, not beliefs. Experimental and longitudinal survey evidence reinforces the finding that the radio program affected socially shared perceptions of typical or prescribed behavior—that is, social norms. Specifically, measurements of perceptions of social norms called into question by Staub and Pearlman are shown to correlate with perceptions of public opinion and public, not private, behaviors. Although measurement issues and the mechanisms of the radio program's influence merit further testing, theory and evidence point to social interactions and emotional engagement, not individual education, as the likely mechanisms of change. The present exchange makes salient what is at stake in this debate: a model of change based on learning and personal beliefs versus a model based on group influence and social norms. These theoretical models recommend very different strategies for prejudice and conflict reduction. Future field experiments should attempt to adjudicate between these models by testing relevant policies in real-world settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
Unlike desktop PC or server applications, multicore devices used in embedded systems are many and diverse. There are many potential approaches to solving the numerous multicore-related issues. The articles in this issue on embedded multicore processors and systems represent a small sampling of these issues. 相似文献
65.
Moshe Gavrielov 《电子产品世界》2009,16(1)
赛灵思(Xilinx)公司总裁兼CEO Moshe Gavrielov现在依然相信,FPGA应用将有许多机会在2009年得到增长。例如,无线基础设备制造商将会在2009年继续开发下一代无线服务设备。从全球角度来看,这就意味着制造商将继续采用FPGA开发创新的3GPPLTE(长期演进技术)和WiMax基站。对于中国来说,这意味着制造商将继续采用FPGA桔术开发创新的TD—SCDMA基站。 相似文献
66.
Aitera:依靠40nm与灵活性突围 谈及未来FPGA的发展趋势,Altera亚太区副总裁兼董事总经理Erhaan Shaikh认为对于面向全球市场采用了单芯片方案的新产品,在不同地区市场上推出时需要提供各种各样的型号产品. 相似文献
67.
The energy interaction curves of a number of diatomic and polyatomic dication systems were calculated in order to study their energy-trapping properties. Generally, the ab initio complete active space multiconfiguration self-consistent field method was used in an extended valence + polarization basis set, with compact effective potentials replacing the core electrons. The diatomic dications include all ten possible binary combinations of oxygen, sulphur, selenium, and tellurium. O22+ shows the largest exothermicity, measured from equilibrium to the monocation combination asymptote, and highest barrier to dissociation. The calculated equilibrium bond length and harmonic vibrational frequency agree very well with experiment. The O22+, SO2+, SeO2+, and TeO2+ series show progressively decreasing exothermicities but similar barrier heights. The non-oxides, in contrast, show similar exothermicities but decreasing barriers with increasing size of the atom constituents. These trends are interpreted in terms of both valence bond curve-crossing and molecular orbital bonding models. The ozone dication, O32+, is found to have a number of low-lying singlet and triplet stationary state structures spanning near-linear to D3h2+ symmetries. Although the calculated exothermicity is even larger than for O22+, the barrier to O2+ + O+ dissociation is predicted to be low in each case. O22+ surrounded by six argon atoms to model an isolating environment shows increased equilibrium O–O bond length, decreased exothermicity, and increased barrier to dissociation, relative to the bare dication. O22+ flanked at each end by a perpendicularly oriented H2 molecule in a staggered conformation is obstructed from direct conversion to the water dimer dication by a high barrier. However, [(H2O)2]2+ dissociates smoothly from equilibrium to two water monocations with a large exothermicity but a small barrier. 相似文献
68.
Conducted 2 experiments to examine developmental changes from middle childhood to adolescence in metaretrieval plans offered to solve different retrieval problems. In each experiment, 80 children in Grades 3, 5, 7, and 9 made judgments about 2 problems that were more or less external or internal . The spontaneous responses from Exp I revealed an age increase in the number of different ideas generated for the internal problem and an age increase in the number of children who recommended the highly general strategy of retracing one's steps for retrieval. The forced-choice judgments in Exp II revealed the perception that the internal problem is more difficult than the external one and some discrepancy between the "best" strategy most often chosen for each retrieval problem (Exp II) and the strategy most frequently mentioned (Exp I). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
The intestine is the organ that contributes the majority of circulating alimentary lipoproteins. Intestinal epithelial cells have the unique ability to elaborate chylomicrons, the largest triglyceride-rich lipoproteins and the main vehicle for the transport of dietary lipids. The final intracellular assembly and exocytosis of chylomicrons require enterocyte-derived apolipoproteins (apo). As research on lipoprotein metabolism evolved, it has become increasingly evident that apo B is a crucial protein for the normal packaging of triglyceride-rich lipoproteins. Immunocytochemical techniques have successfully been used to demonstrate the presence of two types of apo B, the B-100 and the B-48, in different subcellular compartments of the human enterocyte. Confirmation was obtained by biochemically analyzing human lymph and intestine from pediatric patients. In addition, the immunoelectron microscopic approach revealed the location of apo A-I in the rough endoplasmic reticulum (ER) and predominantly in the Golgi apparatus and the basolateral membrane, which confirms the rapid transport of apo A-I documented by other studies. Proven utility and experimental conditions were defined to demonstrate the ability of Caco-2 cells, a colon carcinoma cell line, to esterify lipids, synthesize apo, and assemble lipoproteins. Thus, immunocytochemical and biochemical techniques can be combined with in vivo and in vitro intestinal models for the study of the intestinal lipid transport. 相似文献
70.
Enhanced correction of thermally induced birefringence in the presence of strong single-pass, azimuthally dependent bipolar focusing was achieved in single-rod laser oscillators by use of an adaptive optic rear mirror with image relay and aberration correction capabilities. Together with a Faraday rotator, the imaging variable radius mirror was successfully tested in stable and unstable Nd:Cr:GSGG power oscillators under variable pump power conditions from 0 to 800 W. Birefringence correction in the absence of ray retracing was achieved. 相似文献