14597615
Priority assignment optimization for minimization of current surge in high performance power efficient clock-gated microprocessor
We propose an integrated architectural/physical-planning approach named priority assignment optimization to minimize the current surge in high performance power efficient clock-gated microprocessors. The proposed approach balances the current demands across the floorplan by assigning optimized priorities to the functional units (FUs). Two complementary methods -- physical planning with soft modules and issue pattern management - to enhance our proposed approach are also discussed for various applications. Experimental results show that the proposed approach reduces the peak noise by 11.75% and consequently, the decoupling capacitance (Decap) requirement by 24.22% without any degradation in IPC (Instruction Per Cycle). We also show that our approach does not increase the clock period for the 0.18μm technology and beyond.
54815196
Cascaded carry-select adder (C2SA): a new structure for low-power CSA design
In this paper we propose a novel low-power Carry-Select Adder (CSA) design called Cascaded CSA (CSA). Based on the prediction of the critical path delay of current operation, CSA can automatically work with one or two clock-cycle latency and a scaled supply voltage to achieve power improvement. Post-layout simulations of a 64-bit CSA in 180nm Technology show that CSA can operate at a lower supply voltage, attaining 40.7% energy saving, while maintaining a similar (average) Latency Per Operation (LPO) compared to standard CSA.
207717559
Associative Clustering for Clusters of Arbitrary Distribution Shapes
A novel neural network, named Associative Clustering Neural Network (ACNN), is developed for clustering data whose underlying distribution shapes are arbitrary. ACNN is a dynamic model that collectively measures and updates the similarity of any two patterns through the interaction of a group of patterns. Such a new measure of similarity helps to achieve more robust clustering performance than using the existing measures that are staticly and individually based on the distances among the isolated pairwise data. The efficience of ACNN has been verified through the performance study.
18093029
The Robustness of Localization Algorithms to Signal Strength Attacks: A Comparative Study
In this paper, we examine several localization algorithms and evaluate their robustness to attacks where an adversary attenuates or amplifies the signal strength at one or more landmarks. We propose several performance metrics that quantify the estimator's precision and error, including Holder metrics, which quantify the variability in position space for a given variability in signal strength space. We then conduct a trace-driven evaluation of several point-based and area-based algorithms, where we measured their performance as we applied attacks on real data from two different buildings. We found the median error degraded gracefully, with a linear response as a function of the attack strength. We also found that area-based algorithms experienced a decrease and a spatial-shift in the returned area under attack, implying that precision increases though bias is introduced for these schemes. We observed both strong experimental and theoretic evidence that all the algorithms have similar average responses to signal strength attacks.
5650965
L-Tree: A Dynamic Labeling Structure for Ordered XML Data
With the ever growing use of XML as a data representation format, we see an increasing need for robust, high performance XML database systems While most of the recent work focuses on efficient XML query processing, XML databases also need to support efficient updates To speed up query processing, various labeling schemes have been proposed However, the vast majority of these schemes have poor update performance In this paper, we introduce a dynamic labeling structure for XML data: L-Tree and its order-preserving labeling scheme with O(log n) amortized update cost and O(log n) bits per label L-Tree has good performance on updates without compromising the performance of query processing We present the update algorithm for L-Tree and analyze its complexity.
2308649
Subgoal ordering and granularity control for incremental planning
In this paper, we study strategies in incremental planning for ordering and grouping subproblems partitioned by the subgoals of a planning problem when each sub-problem is solved by a basic planner. To generate a rich set of partial orders for ordering subproblems, we propose a new ordering algorithm based on a relaxed plan built from the initial state to the goal state. The new algorithm considers both the initial and the goal states and can effectively order subgoals in such a way that greatly reduces the number of invalidations during incremental planning. We have also considered trade-offs between the granularity of the subgoal sets and the complexity of solving the overall planning problem. We show an optimal region of grain size that minimizes the total complexity of incremental planning. We propose an efficient strategy to dynamically adjust the grain size in partitioning in order to operate in this optimal region. We further evaluate a redundant-execution scheme that uses two different subgoal orders in order to improve the quality of the plans generated without greatly sacrificing run-time efficiency. Experimental results on using three basic planners (metric-FF, YAHSP, and LPG-TD-speed) show that our strategies are general for improving the time and quality of each of these planners across various benchmarks
18849054
An enhanced buffer management scheme for fast handover protocol
The integration of IEEE 802.11 wireless LAN and mobile IP technologies offers an affordable and high bandwidth solution for host mobility. When applying the hierarchical mobile IP for fast handover, the performance bottleneck on mobile IP and potential disconnection during handoff period can be greatly improved. However, the fast handover protocol suffers several problems such as scalability and QoS support for lacking a buffer management mechanism. We propose an enhanced buffer management scheme for fast handover. By means of the proposed scheme, we are able to improve the buffer utilization on routers as well as to support QoS services during a handoff process. Using the ns-2 simulator, we have demonstrated the significance and effectiveness of our proposed scheme.