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31.
Design and implementation of a vehicle interface protocol using an IEEE 1394 network 总被引:1,自引:0,他引:1
A wide variety of in-vehicle devices such as camera sensors, navigation systems, telematics and communication equipments have been incorporated into a vehicle to realize Intelligent Transport Systems (ITS) applications. Because an efficient standardized network is required, ITS Data Bus (IDB) has been discussed to carry high-speed multimedia data for audio, video and other real-time ITS applications. For connecting devices in a standardized manner, the IDB network has architecture with a gateway called vehicle interface which is located between automaker’s proprietary network and the standardized IDB network. IEEE 1394 (also known as iLink or FireWire), which can transport multimedia data for consumer electronics, is a good candidate for IDB network. In this paper, we analyze the issues for existing AV/C protocol (application layer protocol over IEEE 1394) to comprise the IDB network. In addition, we designed and implemented the vehicle interface protocol as a higher layer of IEEE 1394 to address the AV/C protocol issues for realizing the whole IDB network architecture. 相似文献
32.
A quantum-inspired evolutionary algorithm (QEA) is proposed as a stochastic algorithm to perform combinatorial optimization
problems. The QEA is evolutionary computation that uses quantum bits and superposition states in quantum computation. Although
the QEA is a coarse-grained parallel algorithm, it involves many parameters that must be adjusted manually. This paper proposes
a new method, named pair swap, which exchanges each best solution information between two individuals instead of migration
in the QEA. Experimental results show that our proposed method is a simpler algorithm and can find a high quality solution
in the 0-1 knapsack problem.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
33.
In this study, thermomechanical properties of titanium-nickel (Ti-Ni) shape memory alloy (SMA) films are investigated in order to derive constitutive relations. Ti-Ni SMA films, deposited by DC magnetron sputtering under controlled film composition, are characterized by uniaxial tensile tests. At room temperature (R.T.), Ti-Ni films having Ti contents less than 50 at% exhibit superelastic behavior, and those having Ti contents greater than 50 at% exhibit shape memory behavior. However, the Ni—53.2 at% Ti film fractured at a tensile strain of 0.8% because of an increase in brittleness with increasing Ti content. At elevated temperatures, Ti-Ni films having Ti contents of 50.2 to 52.6 at% undergo phase change from martensite to austenite. The Young's modulus of the Ti-Ni films depends on temperature at each phase, regardless of film composition. Film composition does, however, affect the measured material constants bA, bM, cA, and cM. Stress-strain curves calculated from the constructed constitutive equation closely agree with those obtained from tensile tests, for both the martensite and austenite phases. The constitutive equations are expected to find great utility in the design of Ti-Ni film-actuated microelectromechanical systems (MEMS). 相似文献
34.
Ceramics (alumina) coating on sevaral materials has been successfully achieved at room temperature by gas - assisted deposition ( GAD) technique. In the GAD process the alumina powder was accelerated by jet flow with velocity of - 1000 m/s and impaeted to a substrate, thereby a fiat and dense film was deposited up to 10 μm on the substrate without arty additional heating. The crystal structttre of the alumina in an obtained GAD films seemed as amorphous like. The crystalline phase was recovered by post nnnenling at 1 300 ℃ , however, the matrix resulted in a hollow structure. 相似文献
35.
Summary A simplified analysis of crack growth of piezoelectric ceramics was performed by using the double cantilever beam (DCB) model.
The analysis was intended for the crack growth in a steady state by using some assumptions to simplify the analysis. In the
present paper, damage within piezoelectric ceramics was represented by a damage variable based on the continuum damage mechanics,
and the effect of the damage on material properties was taken into account in a constitutive equation of the piezoelectric
ceramics. The constitutive equation and an evolution equation of the damage variable were applied to the DCB model. Then,
the crack growth in the DCB model was dealt with within the framework of the continuum damage mechanics. As a result of the
analysis, a constant crack growth rate and distribution of stress, strain and damage variable in front of the crack tip were
elucidated, and the effects of the applied electric field on the crack growth were discussed in particular. 相似文献
36.
Baku Katagiri Tetsuya Miyashita Takahiro Ishinabe Tatsuo Uchida 《Journal of the Society for Information Display》2003,11(3):585-590
Abstract— One problem with front‐projection displays is that the screen contrast ratio decreases in bright ambient light. In this paper, we propose a new front‐projection display system that incorporates the control of reflection of ambient light in the screen design, providing a high contrast ratio even in a brightly lit room. 相似文献
37.
Hurfin M. Mizuno M. Raynal M. Singhal M. 《IEEE transactions on pattern analysis and machine intelligence》1998,24(8):664-677
Global predicate detection is a fundamental problem in distributed systems and finds applications in many domains such as testing and debugging distributed programs. This paper presents an efficient distributed algorithm to detect conjunctive-form global predicates in distributed systems. The algorithm detects the first consistent global state that satisfies the predicate even if the predicate is unstable. Unlike previously proposed run-time predicate detection algorithms, our algorithm does not require the exchange of control messages during the normal computation. All the necessary information to detect predicates is piggybacked on computation messages of application programs. The algorithm is distributed because the predicate detection efforts as well as the necessary information are equally distributed among the processes. We prove the correctness of the algorithm and compare its performance with respect to message, storage and computational complexities with that of the previously proposed run-time predicate detection algorithms 相似文献
38.
Human behaviors consist of both voluntary and involuntary motions. Almost all behaviors of task-oriented robots, however, consist solely of voluntary motions. Involuntary motions are important for generating natural motions like those of humans. Thus, we propose a natural behavior generation method for humanoid robots that is a hybrid generation between voluntary and involuntary motions. The key idea of our method is to control robots with a hybrid controller that combines the functions of a communication behavior controller and body balancing controllers. We also develop a wheeled inverted pendulum type of humanoid robot, named “Robovie-III”, in order to generate involuntary motions like oscillation. By applying our method to this robot and conducting preliminary experiments, we verify its validity. Experimental results show that the robot generates both voluntary and involuntary motions. 相似文献
39.
Abstract— Viewing‐angle dependences of the contrast ratio and color shift of LCDs have been radically improved as evidenced by the increasing application of LCDs in high‐quality television. This paper describes the concept of optical compensation and the fundamental characteristics of the viewing‐angle property for various LC modes. 相似文献
40.
薄板矩形盒拉深试验及应力分析 总被引:2,自引:0,他引:2
利用法兰曲边当量半径的简化方法对矩形盒拉深中的直边和曲边侧壁部拉入方向的应力分布进行了分析和计算,其结果与试验和有限元计算结果基本吻合。指出矩形盒短边侧壁拉深方向的应力值较大,沿凹模入口线上,角部拉入应力最大,直边部径向应力在零上下波动,凹模入口线附近局部区域存在法向压缩变形倾向。 相似文献