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Two experiments examined the effects of blocking of word lists (grouped by semantic category membership or randomly ordered) on the dichotic listening performances of 48 2nd and 48 5th graders. For Exp I, shadowing and retention scores were obtained for groups of Ss representing the 4 combinations of blocked and random word lists for targets and distractors. Blocking of distractor lists led to better shadowing scores for 2nd graders. When word pairs were matched by categories in Exp II, 2nd graders who heard blocked lists recognized fewer target words (in retention tests) than did those who heard randomly ordered word lists. Results are interpreted in the context of variables that affect the shadowing performances of younger children and developmental differences in encoding strategies. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Alarcon-Rodriguez A. Haesen E. Ault G. Driesen J. Belmans R. 《Renewable Power Generation, IET》2009,3(2):227-238
The amount of distributed energy resources (DER) in the grid is continually increasing, and the potential benefits and drawbacks are becoming clearer. However, there is still a lack of clarity in how these multiple effects interact and which trade-offs should be made in the integration of new DER. There is a clear need for appropriate DER planning tools in the current market environment, in which both DER operators and distribution system operators (DSOs) may have multiple, often conflicting objectives and where uncertainty remains present as to which targets can be reached with a high amount of DER in the grid. A novel multi-objective planning framework is presented for the integration of stochastic and controllable DER in the distribution grid. A case study that illustrates the proposed framework is presented. Active DER management in terms of curtailment as well as dispatch of units is studied using the proposed multi-objective approach. Additionally, the extent to which active DER can be used as an alternative for grid reinforcements is analysed. The results show that the proposed multi-objective approach permits a better evaluation of the potential of active DER to support system operation. 相似文献
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Dominik Saner Ronnie Juraske Markus Kübert Philipp Blum Stefanie Hellweg Peter Bayer 《Renewable & Sustainable Energy Reviews》2010,14(7):1798-1813
Shallow geothermal systems such as open and closed geothermal heat pump (GHP) systems are considered to be an efficient and renewable energy technology for cooling and heating of buildings and other facilities. The numbers of installed ground source heat pump (GSHP) systems, for example, is continuously increasing worldwide. The objective of the current study is not only to discuss the net energy consumption and greenhouse gas (GHG) emissions or savings by GHP operation, but also to fully examine environmental burdens and benefits related to applications of such shallow geothermal systems by employing a state-of the-art life cycle assessment (LCA). The latter enables us to assess the entire energy flows and resources use for any product or service that is involved in the life cycle of such a technology. The applied life cycle impact assessment methodology (ReCiPe 2008) shows the relative contributions of resources depletion (34%), human health (43%) and ecosystem quality (23%) of such GSHP systems to the overall environmental damage. Climate change, as one impact category among 18 others, contributes 55.4% to the total environmental impacts. The life cycle impact assessment also demonstrates that the supplied electricity for the operation of the heat pump is the primary contributor to the environmental impact of GSHP systems, followed by the heat pump refrigerant, production of the heat pump, transport, heat carrier liquid, borehole and borehole heat exchanger (BHE). GHG emissions related to the use of such GSHP systems are carefully reviewed; an average of 63 t CO2 equivalent emissions is calculated for a life cycle of 20 years using the Continental European electricity mix with 0.599 kg CO2 eq/kWh. However, resulting CO2 eq savings for Europe, which are between ?31% and 88% in comparison to conventional heating systems such as oil fired boilers and gas furnaces, largely depend on the primary resource of the supplied electricity for the heat pump, the climatic conditions and the inclusion of passive cooling capabilities. Factors such as degradation of coefficient of performance, as well as total leakage of the heat carrier fluid into the soil and aquifer are also carefully assessed, but show only minor environmental impacts. 相似文献
25.
Determination of the rheological properties of thermoplastic composites for compression flow molding
The influence of the fiber mat structure and the matrix rheology on the squeeze flow behavior of thermoplastic composites for compression flow molding has been investigated. An analytical model for isothermal squeeze flow has been developed and experimentally confirmed. The model is based on the role of the matrix at local fiber interaction points. The squeeze flow rheology of the composite can be evaluated from the shear flow of the pure matrix as expressed by a Carreau equation, using two micromechanical‐based shift factors. It was found that the fiber mat structure influences the yield stress of the composite, but has a minor influence on the squeeze flow in comparison to the influence of the matrix. 相似文献
26.
Object relations theory and subsequent empirical investigations have established the characteristic ways in which children aged 2–6 yrs utilize transitional objects (e.g., teddy bears or blankets). Three of these characteristics—spontaneity, specificity, and intensity—were used as the primary criteria to investigate the genuineness of hypnotic age regression when Ss were regressed to age 3 and placed in emotional situations typical of those reported clinically. Two groups of college students (16 highly susceptible, as "reals," and 15 low susceptible, as simulators; Ss were administered the Harvard Group Scale of Hypnotic Susceptibility and a version of the Stanford Profile Scales of Hypnotic Susceptibility) behaved differentially on all 3 measures, with reals behaving in a generally more childlike manner, thus suggesting an effect attributable to the hypnotic condition. Further, the behavior of these Ss was compared to that of 77 children aged 1–6 yrs; reals and children were statistically indistinguishable on the 2 criteria on which they were compared, but simulators differed significantly from both groups. This pattern of results, along with real–simulator differences, suggests a more complete reproduction of an earlier affective process as a function of meaningful hypnotic age regression. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
27.
In Europe, market coupling stands for a further integration of wholesale trading arrangements across country borders. More specifically, it refers to the implicit auctioning of cross-border physical transmission rights via the hourly auctions for electric energy organized by power exchanges (PEXs) one day ahead of delivery. It therefore implies that the PEXs can optimize the clearing of their day-ahead auctions. Due to verticals in the aggregated order curves, the optimal solution can be settled at different prices. In order for prices to give correct locational signals for network development, generation and consumption, price coordination between exchanges is necessary. The paper illustrates this issue, its relevance and discusses how to deal with it. 相似文献
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Jiarong Zhou Ashley V. Kroll Maya Holay Ronnie H. Fang Liangfang Zhang 《Advanced materials (Deerfield Beach, Fla.)》2020,32(13):1901255
While traditional approaches for disease management in the era of modern medicine have saved countless lives and enhanced patient well-being, it is clear that there is significant room to improve upon the current status quo. For infectious diseases, the steady rise of antibiotic resistance has resulted in super pathogens that do not respond to most approved drugs. In the field of cancer treatment, the idea of a cure-all silver bullet has long been abandoned. As a result of the challenges facing current treatment and prevention paradigms in the clinic, there is an increasing push for personalized therapeutics, where plans for medical care are established on a patient-by-patient basis. Along these lines, vaccines, both against bacteria and tumors, are a clinical modality that could benefit significantly from personalization. Effective vaccination strategies could help to address many challenging disease conditions, but current vaccines are limited by factors such as a lack of potency and antigenic breadth. Recently, researchers have turned toward the use of biomimetic nanotechnology as a means of addressing these hurdles. Recent progress in the development of biomimetic nanovaccines for antibacterial and anticancer applications is discussed, with an emphasis on their potential for personalized medicine. 相似文献