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31.
32.
We present rules for the unsupervised learning of coincidence between excitatory postsynaptic potentials (EPSPs) by the adjustment of postsynaptic delays between the transmitter binding and the opening of ion channels. Starting from a gradient descent scheme, we develop a robust and more biological threshold rule by which EPSPs from different synapses can be gradually pulled into coincidence. The synaptic delay changes are determined from the summed potential--at the site where the coincidence is to be established--and from postulated synaptic learning functions that accompany the individual EPSPs. According to our scheme, templates for the detection of spatiotemporal patterns of synaptic activation can be learned, which is demonstrated by computer simulation. Finally, we discuss possible relations to biological mechanisms. 相似文献
33.
Leonard L. Gelb Waldo C. Ault William E. Palm Lee P. Witnauer William S. Port 《Journal of the American Oil Chemists' Society》1959,36(7):283-286
Summary and Conclusion Epoxy resins were made from phthalic anhydride and the following expoxidized fatty glycerides: neats-foot oil, lard oil, triolein,
soybean oil, perilla oil, and trilinolein. Some physical properties of these resins were measured and tabulated.
It has been shown that heat-distortion temperature, tensile strength, and modulus of elasticity increase with the unsaturation
of the glyceride precursor of the epoxy intermediate.
Presented at the fall meeting, American Oil Chemists' Society, Chicago, Ill., October 20–22, 1958.
Eastern Regional Research and Development Division, Agricultural Research Service, United States Department of Agriculture. 相似文献
34.
Edmund F. Jordan Jr. William E. Palm William S. Port 《Journal of the American Oil Chemists' Society》1961,38(5):231-233
Coplymers of acrylonitrile containing 5 to 28 mole % (11 to 70 weight %) of three alkyl acrylates (butyl, octyl, and octadecyl)
were prepared in t-butanol solution. The copolymers were capable of being molded at about 300–400°F. under a pressure of about
2,000 p.s.i. The magnitude of both the tensile strength and the characteristic low temperature of the copolymers varied inversely
with the weight percentage of the acrylate present without regard to its alkyl type. The copolymers were oriented with an
accompanying three-fold increase in the tensile strength. Good resistance to several selected reagents was shown by all the
copolymers.
This paper was presented, in part, at the fall meeting. American Oil Chemists' Society, New York, October 1960.
Eastern Utilization Research and Development Division, Agricultural Research Service, U.S. Department of Agriculture. 相似文献
35.
Paulter N.G. Palm R.H. Barry D.D. 《Electronics Packaging Manufacturing, IEEE Transactions on》2008,31(2):150-158
The design, fabrication, and test of a wide-bandwidth (3-dB attenuation bandwidth ges 30 GHz), 50 Omega, passive coaxial probe for the electrical characterization of printed wiring board (PWB) transmission lines is described. The probe can make thousands of repeated contacts, using spring-loaded interconnects, without affecting probe performance. The probe contains an internal mechanism for dissipating static charge on the signal line of the PWB transmission line and is long enough (approximately 10 cm) to act as a transfer standard for characteristic impedance testing, as per the time-domain reflectometry test method described in IPC TM 2.5.5.7. 相似文献
36.
Environmental problems in the energy system often originate from everyday activities and choices. Everyday activities in the home are part of the private sphere that can be contested in relation to energy policies. This article discusses the public–private divide in energy policies and how Swedish municipal energy consultants understand the divide. By analyzing the actions of energy consultants and their efforts to influence households, as well as how households perceive this guidance, I will discuss the public–private discourse in relation to energy policy and how this discourse can be a restriction for the energy consultants to reach their full potential. 相似文献
37.
Experimental results of two-phase pressure drop in a horizontal circular microchannel are reported in this paper. A test tube was made of fused silica having an internal diameter of 781 μm with a total length of 261 mm and a heated length of 191 mm. The outer surface of the test tube was coated with an electrically conductive thin layer of ITO (indium tin oxide) for direct heating of the test section. Refrigerants R134a and R245fa were used as the working fluids, and mass flux during the experiments was varied between 100 and 650 kg/m2-s. Experiments were performed at two different system pressures corresponding to saturation temperatures of 25°C and 30°C for R134a and at three different system pressures corresponding to saturation temperatures of 30°C, 35°C, and 40°C for R245fa. Two-phase frictional pressure drop characteristics with variation of mass flux, vapor fraction, saturation temperature, and heat flux were explored in detail. Finally, the prediction capability of some well-known correlations available in the literature, some developed for macrochannels and others especially developed for microchannels, was assessed. 相似文献
38.
This paper combines engineering and social science approaches to enhance our understanding of industrial energy efficiency and broaden our perspective on policy making in Europe. Sustainable development demands new strategies, solutions, and policy-making approaches. Numerous studies of energy efficiency potential state that cost-effective energy efficiency technologies in industry are not always implemented for various reasons, such as lack of information, procedural impediments, and routines not favoring energy efficiency. Another reason for the efficiency gap is the existence of particular values, unsupportive of energy efficiency, in the dominant networks of a branch of trade. Analysis indicates that different sectors of rather closed communities have established their own tacit knowledge, perceived truths, and routines concerning energy efficiency measures. Actors in different industrial sectors highlight different barriers to energy efficiency and why cost-effective energy efficiency measures are not being implemented. The identified barriers can be problematized in relation to the social context to understand their existence and how to resolve them. 相似文献
39.
40.
Jenny Palm 《突发事故与危机管理杂志》2009,17(1):55-63
This article focuses on households' action space and perceived responsibilities during power outages, and on how municipalities and grid companies understand their own and the households' responsibilities and action space. Results from a case study in the county of Östergötland showed that household responsibilities in terms of preparedness for outages were unclear to the actors. Both municipalities and grid companies expected households to be somewhat prepared. Households, however, believed that they were not responsible for being prepared for power outages, even though they need to be prepared to survive. Often the preparedness concerns material factors, such as investment in auxiliary generating capacity for use in case of outages. How the households perceive outages is important for their capacity to handle and feel comfortable in such situations. 相似文献