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排序方式: 共有10000条查询结果,搜索用时 484 毫秒
981.
根据OSEK/VDX规范,以及μC/OS-Ⅱ内核的特点,分析二者的差异,通过修改μC/OS-Ⅱ内核,设计出一种符合OSEK/VDX规范的车载嵌入式操作系统.并从任务管理与调度、资源管理、警报与计数器管理、事件管理和中断管理等多方面,详细地介绍了该系统的主要设计思想. 相似文献
982.
983.
Yu-Jin ChenAuthor Vitae Gang XiaoAuthor VitaeTie-Shi WangAuthor Vitae Fan ZhangAuthor VitaeYang MaAuthor Vitae Peng GaoAuthor Vitae Chun-Ling ZhuAuthor VitaeEndi ZhangAuthor Vitae Zhi XuAuthor VitaeQiu-hong LiAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(1):270-277
Crystalline α-MoO3/TiO2 core/shell nanorods are fabricated by a hydrothermal method and subsequent annealing processes under H2/Ar flow and in the ambient atmosphere. The shell layer is composed of crystalline TiO2 particles with a diameter of 2-6 nm, and its thickness can be easily controlled in the range of 15-45 nm. The core/shell nanorods show enhanced sensing properties to ethanol vapor compared to bare α-MoO3 nanorods. The sensing mechanism is different from that of other one-dimensional metal oxide core/shell nanostructures due to very weak response of TiO2 nanoparticles to ethanol. The enhanced sensing properties can be explained by the change of type II heterojunction barrier formed at the interface between α-MoO3 and TiO2 in the different gas atmosphere. The present results demonstrate a novel sensing mechanism available for gas sensors with high performance. 相似文献
984.
Theoretical and experimental study of capacitance considering fabrication process and edge effect for MEMS comb actuator 总被引:1,自引:1,他引:0
This paper introduces a new theoretical model of plate capacitor for MEMS comb actuator. In this model, bulk fabrication process
and edge effect are both considered using integration method and conformal transformation theory. In order to verify the correctness
of the model, FEM software is used to calculate the value of the capacitance of the MEMS comb actuator. The simulated result
is 1.441 pF. Relative errors to the model calculated result 1.401 pF and ideal model calculated result 1.267 pF are 2.78 and
12.07% respectively. Then, high precision capacitance measuring device is used to measure the micro-fabricated comb actuator.
The tested result is 1.517 pF. Its relative error to the rectified value is 7.65%, much less than the relative error to ideal
result 16.48%. This further indicates the correctness of the rectified model. 相似文献
985.
现有的语义Web服务匹配算法没有考虑到本体概念间的多元关系,导致概念的语义不能被完整地反映出来,从而影响了算法的匹配性能。利用本体概念间的多元关系定义了一种语义距离,并通过该语义距离给出了概念间的语义相似度计算方法,在此基础上提出基于语义相似度的Web服务匹配算法。该算法通过本体概念间的语义相似度来反映Web服务的匹配程度。最后,通过对比实验验证了该算法的可行性和有效性。 相似文献
986.
987.
Zhe Fan Yu-Chuan Kuo Ye Zhao Feng Qiu Arie Kaufman William Arcieri 《The Visual computer》2009,25(11):985-996
We present a simulation and visualization system for a critical application—analysis of the thermal fluid dynamics inside
a pressurized water reactor of a nuclear power plant when cold water is injected into the reactor vessel. We employ a hybrid
thermal lattice Boltzmann method (HTLBM), which has the advantages of ease of parallelization and ease of handling complex
simulation boundaries. For efficient computation and storage of the irregular-shaped simulation domain, we classify the domain
into nonempty and empty cells and apply a novel packing technique to organize the nonempty cells. This method is implemented
on a GPU cluster for acceleration. We demonstrate the formation of cold-water plumes in the reactor vessel. A set of interactive
visualization tools, such as side-view slices, 3D volume rendering, thermal layers rendering, and panorama rendering, are
provided to collectively visualize the structure and dynamics of the temperature field in the vessel. To the best of our knowledge,
this is the first system that combines 3D simulation and visualization for analyzing thermal shock risk in a pressurized water
reactor. 相似文献
988.
A distributed approach to enabling privacy-preserving model-based classifier training 总被引:4,自引:4,他引:0
Hangzai Luo Jianping Fan Xiaodong Lin Aoying Zhou Elisa Bertino 《Knowledge and Information Systems》2009,20(2):157-185
This paper proposes a novel approach for privacy-preserving distributed model-based classifier training. Our approach is an
important step towards supporting customizable privacy modeling and protection. It consists of three major steps. First, each
data site independently learns a weak concept model (i.e., local classifier) for a given data pattern or concept by using
its own training samples. An adaptive EM algorithm is proposed to select the model structure and estimate the model parameters simultaneously. The second step deals with combined classifier training by integrating the weak concept models that are shared from multiple data sites. To reduce the data transmission costs and
the potential privacy breaches, only the weak concept models are sent to the central site and synthetic samples are directly generated from these shared weak concept models at the central site. Both the shared weak concept models and
the synthetic samples are then incorporated to learn a reliable and complete global concept model. A computational approach is developed to automatically achieve a good trade off between the privacy disclosure risk, the
sharing benefit and the data utility. The third step deals with validating the combined classifier by distributing the global
concept model to all these data sites in the collaboration network while at the same time limiting the potential privacy breaches.
Our approach has been validated through extensive experiments carried out on four UCI machine learning data sets and two image
data sets.
相似文献
Jianping FanEmail: |
989.
模乘运算是公钥密码算法中的关键运算,本文基于全字运算的Montgomery模乘算法,设计了具有可伸缩硬件结构的模乘器。该模乘器可以基于固定的数据路径宽度对任意长度的数据进行运算,并且能够支持两个有限域上的运算。最后用Verilog硬件描述语言对该乘法器的硬件结构进行代码设计,并用Synopsys公司的Design Complier在Artisan SIMC 0.18μm typical工艺库下综合。实验结果表明,相对于其他模乘器设计,本文设计具有较高的时钟频率,并且由于大大减少了运算所需的时钟周期数,模乘运算速度较快。 相似文献
990.