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51.
52.
低成本MEMS陀螺实时滤波方法 总被引:1,自引:0,他引:1
为找到一种普遍适合低成本MEMS陀螺仪的随机误差实时处理方法,利用Allan方差分析法首先对MEMS陀螺仪进行分析,根据其误差特性进而设计了平均滤波算法以剔除粗大误差,然后使用最小二乘法,通过拟合前一段历史结果得到下一时刻输出的预测值,基于以上工作最终设计出Kalman滤波器对所输出进行滤波。由于将最小二乘法的推测作为预测过程,避免了系统状态模型难以准确建立的问题。该方法动态性能好,具有普适性。实验结果证明,该方法在静态和动态下均能有效工作,滤波后常值漂移被有效补偿,角度随机游走不再占误差的主要成分,均方差小于滤波前的十分之一。 相似文献
53.
Xue Dou 《International journal of human-computer interaction》2016,32(4):352-362
Horizontal swiping has become a common interaction technique on smartphones, yet many mobile websites do not incorporate this functionality, instead requiring users to scroll down or click on buttons, arrow keys, and other hotspots. This is perhaps because user studies comparing swiping with other interaction techniques are scarce. An experiment was conducted (N = 252) to inform this issue by investigating whether and how adding the swiping functionality to a tap-only mobile website influences users’ intentions to use the website. The data revealed that the addition of swiping technique positively affected behavioral intentions to use the website. Perceived enjoyment was a key variable that explained this effect. These findings have design implications for mobile websites. 相似文献
54.
Internet Data Center (IDC) is one of important emerging cyber-physical systems. To guarantee the quality of service for their worldwide users, large Internet service providers usually operate multiple geographically distributed IDCs. The enormous power consumption of these data centers may lead to both huge electricity bills and considerable carbon emissions. To mitigate these problems, on-site renewable energy plants are emerging in recent years. Since the renewable energy is intermittent, greening geographical load balancing (GGLB for short) has been proposed to reduce both the electricity bills and carbon emissions by following the renewables. However, GGLB is not able to well deal with the wildly fluctuating wind power when applied into IDCs with on-site wind energy plants. It may either fail to minimize the total electricity bills or incur the costly frequent on–off switching of servers. In order to minimize the total electricity bills of geographically distributed IDCs with on-site wind energy plants, we formulate the total electricity bills minimization problem and propose a novel two-time-scale load balancing framework TLB to solve it. First, TLB models the runtime cooling efficiency for each IDC. Then it predicts the future fine-grained (e.g., 10-min) on-site wind power output at the beginning of each scheduling period (e.g., an hour). After that, TLB transforms the primal optimization problem into a typical mixed-integer linear programming problem and solves it to finally obtain the optimal scheduling policy including the open server number as well as the request routing policy. It is worth noting that the open server number of each IDC will remain the same during each scheduling period. As an application instance of TLB, we also design a two-time-scale load balancing algorithm TLB-ARMA for our experimental scenario. Evaluation results based on real-life traces show that TLB-ARMA is able to reduce the total electricity bills by as much as 12.58 % compared with the hourly executed GGLB without incurring the costly repeated on–off switching of servers. 相似文献
55.
Xiaotong Wu Meng Liu WanChun Dou Longxiang Gao Shui Yu 《Peer-to-Peer Networking and Applications》2016,9(1):28-41
Taking advantage of the huge potential of consumers’ untapped computing power, self-organizing cloud is a novel computing paradigm where the consumers are able to contribute/sell their computing resources. Meanwhile, host machines held by the consumers are connected by a peer-to-peer (P2P) overlay network on the Internet. In this new architecture, due to large and varying multitudes of resources and prices, it is inefficient and tedious for consumers to select the proper resource manually. Thus, there is a high demand for a scalable and automatic mechanism to accomplish resource allocation. In view of this challenge, this paper proposes two novel economic strategies based on mechanism design. Concretely, we apply the Modified Vickrey Auction (MVA) mechanism to the case where the resource is sufficient; and the Continuous Double Auction (CDA) mechanism is employed when the resource is insufficient. We also prove that aforementioned mechanisms have dominant strategy incentive compatibility. Finally, extensive experiment results are conducted to verify the performance of the proposed strategies in terms of procurement cost and execution efficiency. 相似文献
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The formal specification of design patterns is central to pattern research and is the foundation of solving various pattern-related problems.In this paper,we propose a metamodeling approach for pattern specification,in which a pattern is modeled as a meta-level class and its participants are meta-level references.Instead of defining a new metamodel,we reuse the Unified Modeling Language(UML)metamodel and incorporate the concepts of Variable and Set into our approach,which are unavailable in the UML but essential for pattern specification.Our approach provides straightforward solutions for pattern-related problems,such as pattern instantiation,evolution,and implementation.By integrating the solutions into a single framework,we can construct a pattern management system,in which patterns can be instantiated,evolved,and implemented in a correct and manageable way. 相似文献
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P2P作为一种崭新的传输模式,不仅能提供隐私保护与匿名通信,还能提高网络的健壮性和抗毁性。然而,P2P技术也由于其自身存在的一些缺陷。文章在对P2P技术简要论述的基础上,重点分析目前P2P系统安全的各种威胁以及防御体系的建设。 相似文献
60.
为了把移动雷达实时数据传输到北京市气象局,通过对比多种无线通信方式以及卫星通信的优缺点等方法建立了一套卫星通信系统。结果表明:本系统在应急、网络速率、安全等方面都能满足移动雷达系统对数据通信的要求。这套系统的设计将对应急系统的建立具有一定的指导意义。 相似文献