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排序方式: 共有538条查询结果,搜索用时 24 毫秒
11.
Fumiaki Shiraishi 《程序员》2006,(9):34-39
对于如何提供补丁下载,单机PC游戏开发人员已经是轻车熟路了,这些补丁包里通常包含玩家需要手动更新的数据和二进制文件.但基本上.他们很少会为了补丁下载而创建一个“更新系统”。 相似文献
12.
Crystals of ethyl p-chloro α-cyano-β-methyl-cis-cinnamate, C13H12NO2Cl, are orthorhombic, space group Pbcn, with eight molecules per unit cell, a = 17.31, b = 8.68 and c = 17.20 Å. The structure was solved by direct methods and refined subsequently by Fourier techniques. The benzene ring makes a dihedral angle of 60.0° with the ethylenic group. This suggests significant steric effects of the β-methyl group and of the carbonyl group on the orientation of the benzene ring. The conformation of the ethylene bond and the carbonyl group around the Cα? C bond is roughly cisoid and the angle of twist is 16.5°. Nearest-neighbour >C = C <groups make contact across a two-fold axis at a center-to-center distance of 4.33 Å. 相似文献
13.
Fumiaki Kobayashi Toru Ogawa Mitsuo Akabori Yoshio Kato 《Journal of the American Ceramic Society》1995,78(8):2279-2281
Uranium-plutonium nitride is a candidate fuel for fast reactors, but its major drawback is 14 C formation from natural nitrogen. One would probably have to use highly 15 N-enriched nitrogen. A pyrochemical process with molten-salt electroreflning has been proposed as a means to increase the nuclear proliferation resistance of the fuel cycle. Molten-salt electroreflning could also be applied to nitride fuels to make possible the recycling of 15 N. The anodic dissolution behavior of UN in LiCI-KCI melt was studied to provide the basis for a feasibility study of electroreflning of irradiated nitride fuels. 相似文献
14.
This article describes the development and use of broken probes: prompted processes of degradation that produce unique identifiers with which to associate and retrieve digitally recorded histories. We offer our design and deployment of Broken Probes as a methodology for eliciting insights into how broken objects and acts of breakage may be given new life through their integration with ubiquitous computing technologies. Based on these developments, we introduce the genre of worn media—a variety of computational material with which to frame and critically examine the manifestation of wear among digital things. We end by discussing how the genre of worn media sensitizes designers and Ubicomp researchers to issues of incompleteness, impermanence, and imperfection to help account for the ethical, material, and historical terms of endurance in a digital age. 相似文献
15.
Electro-rheological (ER) effect of a blend composed of two liquid crystalline materials with different molecular weights is described in this article. The results indicated that ER effect of the blend was observed at the temperature range where each neat sample did not show ER effect. Furthermore, both storage modulus (G′) and loss modulus (G″) decreased drastically at the temperature range for the blend in dynamic viscoelastic measurements. We show that steady ER effect could be obtained by using a blend made up of two liquid crystalline components, whereas remarkable increment in shear stress was not observed for each component under applied electric field. 相似文献
16.
17.
Attempts were made to estimate the fibre axial compressive strength of pitch-based graphitized and polyarylate fibres, and the relationship between the compressive strength and fibre diameter was investigated. The estimated compressive strength of fibres decreases with increasing temperature. This decrease in compressive strength may be accounted for by a decrease in the radial compressing force. There is a linear relationship between the estimated compressive strength and radial compressing force in a temperature range from room temperature to 80°C. The real compressive strength of the fibres, determined by extrapolating this straight line until the radial compressing force is zero, increases with decreasing fibre diameter, but remains almost unchanged at a diameter range smaller than 10 m. In order to obtain reinforcing fibres having a higher compressive strength, it will be necessary to prepare fibres having a diameter smaller than 10 m. 相似文献
18.
Marc Karle Johannes W?hrle Junichi Miwa Nils Paust G��nter Roth Roland Zengerle Felix von Stetten 《Microfluidics and nanofluidics》2011,10(4):935-939
We demonstrate controlled transport of superparamagnetic beads in the opposite direction of a laminar flow. A permanent magnet
assembles 200 nm magnetic particles into about 200 μm long bead chains that are aligned in parallel to the magnetic field
lines. Due to a magnetic field gradient, the bead chains are attracted towards the wall of a microfluidic channel. A rotation
of the permanent magnet results in a rotation of the bead chains in the opposite direction to the magnet. Due to friction
on the surface, the bead chains roll along the channel wall, even in counter-flow direction, up to at a maximum counter-flow
velocity of 8 mm s−1. Based on this approach, magnetic beads can be accurately manoeuvred within microfluidic channels. This counter-flow motion
can be efficiently be used in Lab-on-a-Chip systems, e.g. for implementing washing steps in DNA purification. 相似文献
19.
Fumiaki Okushi Allen Van Gelder 《Annals of Mathematics and Artificial Intelligence》2004,40(3-4):373-401
Model elimination is a back-chaining strategy to search for and construct resolution refutations. Recent extensions to model elimination, implemented in Modoc, have made it a practical tool for satisfiability checking, particularly for problems with known goals. Many formulas can be refuted more succinctly by recording certain derived clauses, called lemmas. Lemmas can be used where a clause of the original formula would normally be required. However, recording too many lemmas overwhelms the proof search. Lemma management has a significant effect on the performance of Modoc. Earlier research studied pure persistent (global) strategies, and pure unit-lemma (local) strategies. This paper describes and evaluates a hybrid strategy to control the lifetime of lemmas, as well as a new technique for deriving certain lemmas efficiently, using a lazy strategy. Unit lemmas are recorded locally as in previous practice, but certain lemmas that are considered valuable are asserted globally. A range of functions for estimating value is studied experimentally. Criteria are reported that appear to be suitable for a wide range of application-derived formulas. 相似文献
20.
Damping characteristics and frequency characteristics of ferro fluid bearing (FFB) spindles were measured using a high-frequency vibration base driven by a piezo actuator. Using the high-frequency vibration base, high-frequency excitation was added to ferro fluid bearing spindles mounted on the vibration base, and it was proved that ferro fluid bearing spindles have effective damping. And the damping effect became larger with higher spindle rotational speed. Also we have measured spindle runout of a ferro fluid bearing spindle using a lock-in amplifier to increase S/N ratio and succeeded to measure nano meter order displacements. 相似文献