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81.
D. J. White 《OR Spectrum》1994,15(4):225-230
In this paper we present three algorithms for solving a problem in which it is required to get an optimal compromise between the average expected reward per unit time and the variance of the reward per unit time. The algorithms lead to an-optimal solution, where>0 is arbitrary. 相似文献
82.
Tatsuki Oda Masafumi Shirai Naoshi Suzuki Kazuko Motizuki 《Journal of Superconductivity》1994,7(3):555-558
The lattice dynamics of an oxide spinel LiTi2O4 is studied by taking account of the electron-phonon (EP) interaction derived on the basis of the realistic tight-binding bands fitted to the first-principles bands. Due to the characteristic dependences of the EP interaction on wavevectors and vibrational modes, a remarkable frequency renormalization of the O vibrational modes, which hybridize with the Ti vibrational modes, is obtained over a wide region of the Brillouin zone. The overall features of the calculated phonon density of states are in agreement with those observed by the inelastic neutron scattering measurements. By using the EP interaction and the renormalized phonon frequencies we have calculated the EP spectral function
2
F(). The superconducting transition temperature, gap function, and tunneling spectra are calculated by solving the Éliashberg equation. The results agree well with the observations. 相似文献
83.
84.
Yubao Li Jingchao Xiao Xinqi Cao Zhiwei Gu Wei Zhang 《Advanced functional materials》2023,33(17):2213385
Here an IR-heating chemical vapor deposition (CVD) approach enabling fast 2D-growth of WSe2 thin films is reported, and the great potential of metal contact doping in building CVD-grown WSe2-based lateral homojunction is demonstrated by contacting with TiN/Ni metals in favor of holes/electrons injection. Shortening nanosheet channel to ≈2 µm leads to pronounced enhancement in the performance of diode. The fabricated WSe2-based diode exhibits high rectification ratios without the need of gate modulation and can work efficiently as photovoltaic cell, with maximum open circuit voltage reaching up to 620 mV and a high power conversion efficiency over 15%, empowering it as superb self-powered photodetector for visible to near-infrared lights, with photoresponsivity over 0.5 A W−1 and a fast photoresponse speed of 10 µs under 520 nm illumination. It is of practical significance to achieve well-performed photovoltaic devices with CVD-grown WSe2 using fab-friendly metals and simple processing, which will help pave the way toward future mass production of optoelectronic chips. 相似文献
85.
High Conductivity in Molecularly p‐Doped Diketopyrrolopyrrole‐Based Polymer: The Impact of a High Dopant Strength and Good Structural Order
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Yevhen Karpov Tim Erdmann Ivan Raguzin Mahmoud Al‐Hussein Marcus Binner Uwe Lappan Manfred Stamm Kirill L. Gerasimov Tetyana Beryozkina Vasiliy Bakulev Denis V. Anokhin Dimitri A. Ivanov Florian Günther Sibylle Gemming Gotthard Seifert Brigitte Voit Riccardo Di Pietro Anton Kiriy 《Advanced materials (Deerfield Beach, Fla.)》2016,28(28):6003-6010
86.
The principal behaviorally active volatile component (ca. 90% +) of the sex pheromone glands ofLutzomyia longipalpis from Jacobina. Brazil, has been isolated and characterized as a novel homosesquiterpene with the structure 3-methyl--himachalene (C16H26). A minor component (ca. 10%) of the gland extract has also been identified as the sesquiterpene-himachalene (C15H24). This work confirms that there are at least 3 members of theL. longipalpis species complex. 相似文献
87.
非线性延迟积分微分方程单支方法的散逸性 总被引:1,自引:0,他引:1
本文研究了非线性延迟积分微分方程单支方法的散逸性.把G(c3P30)-代数稳定的单支方法应用到以上方程中,得到了在有限维空间和无限维空间的散逸性结果.文章最后,数值试验验证了本文的结论. 相似文献
88.
S. Nath 《Computer Physics Communications》2009,180(11):2392-2393
89.
A novel square ring printed antenna has been suggested for dual‐band circular polarization (CP). The geometry contains a square patch and a square ring structure for dual‐band operation. Circular polarization is achieved using triangular cut at the boundary and right angle bend with inner perturbation. The suggested antenna is excited from the lower layer through electromagnetic (EM) coupling technique. The antenna shows good impedance bandwidths of 90 MHz (2.43‐2.52 GHz) and 800 MHz (5.7‐6.5 GHz, respectively. The antenna shows 3 dB axial ratio bandwidth of 20 MHz at lower band and 120 MHz at upper band with improved gain > 6 dBi. The simulated and measured results are well agreed with each other. The antenna is promising wideband operation at the upper band. This antenna was implemented on fiberglass reinforcement laminated Arlon substrate with dielectric constant (?r = 2.55), and the overall physical dimension of 30 × 30 × 3.048 mm3. The designed antenna can be extensibly applicable in WLAN/Wi‐MAX communication. The presented antenna is designed using hyperlynx IE3D and the simulated results are presented. 相似文献
90.
BoD协议中 可以 通过充分利用按需分配后剩余的带宽来降低时延。首先针对如何高效地利用剩余带宽及其对反馈控制的影响,提出了一种新型的基于预测和星上反馈控制的BoD带宽请求分配算法。其次根据网络流量同时呈现长相关和短相关特性,提出采用ARFIMA(p,d,q)模型进行流量建模与预测,该模型根据参数d的取值不同既能表示长相关又能表示短相关。最后利用OPNET软件建立仿真系统。仿真结果表明,对于长相关和短相关业务流,基于ARFIMA(p,d,q)模型预测和星上反馈控制的BoD带宽请求分配方案能够最高效地利用剩余带宽来降低时延。 相似文献