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101.
An Lu Wenbin Fang Chang Xu Shing-Chi Cheung Yu Liu 《Frontiers of Computer Science in China》2010,4(3):354-364
A radio-frequency identification (RFID) system including hardware and software may be updated from time to time after first
time deployment. To ensure the reliability of the system, extensive tests are required. However, enumerating all test cases
is infeasible, especially when the tests involve time-consuming hardware operations. To solve this problem, we propose a testing
methodology for RFID systems which does not enumerate all test cases but rather those which are representative. A clustering
method is adopted in selecting representative test cases. Although a small number of selected test cases are run, we can still
obtain a relatively high bug detection rate compared with running the enumerated test cases. Our extensive experiments show
the efficiency and effectiveness of our testing methodology. 相似文献
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An increasing interest has been shown in microfluidic systems due to their properties including low consumption of reagents, short analysis time and easy integration. However, despite of these advantages over conventional methods, some limitations in sensitivity and selectivity still exist in microfluidic systems. Recently advancements in nanotechnology offer some new approaches for the detection of target analytes with high sensitivity and selectivity. As a result, it is an appropriate method to enhance the detection sensitivity through a combination between microfluidic system and nanotechnology. Optical detection is a dominant technique in microfluidics because of its noninvasive nature and easy coupling. Numerous studies that integrate optical microfluidic system with nanotechnology have been reported in recent years. Therefore, optical microfluidic systems in combination with nanomaterials (NMs) are reviewed in our work. We illustrate the functions of different NMs in optical microfluidic systems and the efforts of different researchers to improve the performance of devices. After the introduction of different nanoparticle-based optical detection methods, challenges and future directions in the development of nanoparticle-based optical detection schemes in microfluidics have also been discussed. 相似文献
104.
为研究列车碰撞性能,用Adams创建由车体、车钩缓冲装置、端部吸能结构、防爬器、转向架和轮轨力等组成的单节车厢三维动力学模型,并创建6节车厢列车的三维动力学模型,模拟列车以15 m/s的速度与2节静止车厢碰撞的过程.通过分析各节车厢的速度、加速度和每个车钩缓冲装置的相对偏移量在碰撞过程中的变化情况,重现列车碰撞过程,进而分析影响列车垂向爬车和横向屈曲稳定性的因素.仿真结果表明,碰撞过程中每个车钩缓冲装置的相对偏移量和列车各节车厢的加速度最大值均沿列车运行向不断变小;列车前三节车厢的垂向爬车和横向屈曲最严重,转向架发生出轨现象. 相似文献
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108.
On optimization of expertise matching with various constraints 总被引:1,自引:0,他引:1
Wenbin TangAuthor Vitae Jie TangAuthor VitaeTao LeiAuthor Vitae Chenhao TanAuthor VitaeBo GaoAuthor Vitae Tian LiAuthor Vitae 《Neurocomputing》2012,76(1):71-83
This paper studies the problem of expertise matching with various constraints. Expertise matching, which aims to find the alignment between experts and queries, is a common problem in many applications such as conference paper-reviewer assignment, product-reviewer alignment, and product-endorser matching. Most existing methods formalize this problem as an information-retrieval problem and focus on finding a set of experts for each query independently. However, in real-world systems, various constraints are often needed to be considered. For example, in order to review a paper, it is desirable that there is at least one senior reviewer to guide the reviewing process. An important question is: “Can we design a framework to efficiently find the optimal solution for expertise matching under various constraints?” This paper explores such an approach by formulating the expertise matching problem in a constraint-based optimization framework. In the proposed framework, the problem of expertise matching is linked to a convex cost flow problem, which guarantees an optimal solution under various constraints. We also present an online matching algorithm to support incorporating user feedbacks in real time. The proposed approach has been evaluated on two different genres of expertise matching problems, namely conference paper-reviewer assignment and teacher-course assignment. Experimental results validate the effectiveness of the proposed approach. Based on the proposed method, we have also developed an online system for paper-reviewer suggestions, which has been used for paper-reviewer assignment in a top conference and feedbacks from the conference organizers are very positive. 相似文献
109.
在无阻尼的假定下,建立并求解了不对称引水系统双调压井涌波的二元二阶微分方程组.研究表明:双调压井涌波存在两个波动频率,任意一个调压井涌波波动为两个波函数之和,而涌波波幅与引水系统水力参数、涌波方程的初始条件有关.以某电站为例,采用两机组导叶瞬间关闭的假定处理初始条件,研究调压井涌波波幅与引水系统水力参数的关系,揭示了不对称双调压井引水系统控制工况下,小机组对应的小调压井涌波波幅在一定范围内并不随着调压井面积的增加而减少的特殊现象.提出不对称引水系统双调压井的面积设计还应根据涌波波幅与调压井面积的变化曲线、避开使得调压井涌波波幅较大的区域的观点. 相似文献
110.
以管网年费用折算值为目标函数,以管网布置形式及管径为优化参数,建立了树状供水管网的优化设计模型.利用基于整数编码的粒子群算法对这一模型进行了求解,该方法以某一管网连接状态及各管段管径作为粒子群个体,采用整数编码,通过不断地更新粒子的位置来搜索最优的管网结构及管径值,实现了对管网布置形式及管径的同时优化.优化过程中,对进化过程中产生的不可行解进行处理,提高了优化效率.实例表明,将粒子群算法应用于树状管网优化设计中可以获得更好的优化结果和效率. 相似文献