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排序方式: 共有78条查询结果,搜索用时 312 毫秒
1.
Electrocatalysts: Guided Evolution of Bulk Metallic Glass Nanostructures: A Platform for Designing 3D Electrocatalytic Surfaces (Adv. Mater. 10/2016) 下载免费PDF全文
Gustavo Doubek Ryan C. Sekol Jinyang Li Won‐Hee Ryu Forrest S. Gittleson Siamak Nejati Eric Moy Candy Reid Marcelo Carmo Marcelo Linardi Punnathat Bordeenithikasem Emily Kinser Yanhui Liu Xiao Tong Chinedum O. Osuji Jan Schroers Sundeep Mukherjee André D. Taylor 《Advanced materials (Deerfield Beach, Fla.)》2016,28(10):1902-1902
2.
Yipeng LiuAuthor VitaeHsing Kenneth ChengAuthor Vitae Qian Candy TangAuthor VitaeEnes EryarsoyAuthor Vitae 《Decision Support Systems》2011,51(1):99-107
We develop an analytical model that embeds empirical findings on software diffusion to examine optimal pricing strategies for a spreadsheet software product under coalescing effects of piracy and word-of-mouth through its entire life cycle. We find that the demand of the innovators has the most significant impact on the firm's pricing decision. Our research recommends market skimming pricing strategy if innovators' demand is high and the market penetration pricing strategy is preferred otherwise. Surprisingly, the increase of conversion rate of imitators to buyers never significantly alters the pricing strategy pre-determined by the demand of innovators. Most interestingly, the optimal profit from instituting a two prices policy for a software product with five years lifespan outperforms that from a one price policy by no more than 4%, a finding that corroborates the common one price policy observed in reality. 相似文献
3.
Jean-Pierre Candy Pierre Fouilloux Michel Keddam Hisasi Takenouti 《Electrochimica acta》1981,26(8):1029-1034
Impedances of a gold-powder and a Raney-gold electrode were measured over a wide frequency range, and were found to be very similar to those of cylindrical pore of finite depth. The simulation calculation for sphere-packed electrode impedance was performed. It was observed that even though each sphere-layer shows the impedance related to an occluded pore-shape, the overall impedance is similar to that of a cylindrical pore electrode. When the penetration depth approaches the pore depth, the shape of the pore wall has little influence on the impedance. Thus, impedance measurement techniques can be applied to porous electrodes of more intricate pore-texture, and evaluate the radius, depth and pore number of its equivalent cylindrical pore electrode. These values determined for a Raney-gold electrode are in very good agreement with those determined by other methods. The case of a more realistic fuel cell electrode such as Raney-nickel with a metal-electrolyte-gas system, was also tentatively examined. 相似文献
4.
High quality analog-to-digital conversions are obtained using simple and inexpensive circuits that require no high-precision components. Samples of the analog signal are cycled rapidly through a coarse quantizer while the roundoff error is fed back and subtracted from the input. By means of this feedback, the coarse quantizations are caused to oscillate between levels, keeping their running average representative of the input. A binary coding of the quantized values, summed over Nyquist intervals, provides a high resolution PCM output. The precision is determined by a product of the cycle rate and the spacing of the coarse quantization levels. The system is surprisingly tolerant of inaccuracies in gains and threshold settings; indeed, it has many of the desirable properties of classical feedback servomechanisms. An 8-bit limit cycling converter intended for 1-MHz signal bandwidths has been fabricated of standard components that, in total, cost less than $150. 相似文献
5.
6.
This paper describes a companded analog-to-digital (A/D) converter for voiceband signals that is simple and potentially inexpensive. The converter uses only 18 coarsely spaced analog levels. Fine resolution is obtained by oscillating between these levels at an increased speed and averaging the result over a Nyquist interval. The companding used in the converter is effectively the same as that of μ-255 pulse-code modulation (PCM). In the encoding process a one-bit code is generated at 256 000 samples/s. This 1-bit per sample signal can be transmitted and decoded directly, or a simple digital circuit will produce a 13-bit, 8-kHz linear PCM signal that can be compressed to 8-bit companded PCM format. In this paper the basic operation of the 1-bit coder is described and its performance when connected to a 1-bit decoder is illustrated. Methods for obtaining both linear and compressed PCM are then presented, and the properties of these PCM signals with respect to noise, gain tracking, and harmonic content are described. Relative insensitivity to circuit component variations, absence of analog gates, along with the need to generate only a few analog levels, make the coder especially well suited to integrated circuit realization. 相似文献
7.
Wang J Candy TR Teel DF Jacobs RJ 《Journal of the Optical Society of America. A, Optics, image science, and vision》2008,25(9):2263-2270
Although the longitudinal chromatic aberration (LCA) of the adult eye has been studied, there are no data collected from the human infant eye. A chromatic retinoscope was used to measure cyclopleged infant and adult refractions with four pseudomonochromatic sources (centered at 472, 538, 589, and 652 nm) and with polychromatic light. The LCA of the infant eyes between 472 and 652 nm was a factor of 1.7 greater than the LCA found in the adult group: infant mean=1.62 D, SD+/- 0.14 D; adult mean=0.96 D, SD+/- 0.17 D. The elevated level of LCA in infant eyes is consistent with the greater optical power of the immature eye and indicates similar chromatic dispersion in infant and adult eyes. The implications for visual performance, defocus detection, and measurement of refraction are discussed. 相似文献
8.
Florina Stefanoiu Laure Candy Carlos Vaca‐Garcia Elisabeth Borredon 《European Journal of Lipid Science and Technology》2008,110(5):441-447
Alkenyl succinic anhydrides (ASA) were obtained by reaction between maleic anhydride and high‐oleic sunflower oil (HOSO) esters. A kinetics study of the maleinization of alkyl esters indicated that the maleinization reaction was second order overall and first order with respect to the individual reactants, and the activation energy was 77.2 ± 3.3 kJ/mol in the investigated temperature range (185–225 °C). These results showed that the cis configuration and the central position of the double bond in HOSO esters facilitate the maleinization of the latter. On the contrary, the length of the linear ester moiety had no influence on the course of the maleinization reaction. Moreover, new evidence demonstrates that there are two different reaction mechanisms: ene‐reaction and addition in allylic position with a 2 : 1 ratio, respectively. This ratio was constant throughout the reaction, thus indicating that these mechanisms are independent. 相似文献
9.
S. L. Tang Raymond T. M. Aoieong Candy S. L. Tsui 《Canadian Metallurgical Quarterly》2009,25(4):204-213
Design is one of the most important aspects in the engineering project cycle. To improve the quality of engineering consulting firms, various quality techniques and practices have been proposed by researchers. Most researchers agree that the successful implementation of such quality practices depends on the quality culture of the consultant organization. Therefore, a thorough understanding of the overall quality culture that exists in a consultant organization is essential. The purpose of this paper is to develop a pragmatic tool, a quality culture auditing (QCA) questionnaire, which enables engineering consulting firms to measure the quality culture quantitatively through a scoring system. The responses obtained from 30 engineering consulting firms that participated in the QCA show that the scores obtained can be a good indicator of a consultant organization’s current quality culture. Using these results as the basis, benchmarking exercises and parametric studies can also be conducted. Through the use of QCA, an engineering consultant can pinpoint areas of weakness so that more effort can be put into these areas for future improvement. 相似文献
10.
Guided Evolution of Bulk Metallic Glass Nanostructures: A Platform for Designing 3D Electrocatalytic Surfaces 下载免费PDF全文