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131.
Dongsoo Kang Chen Liu Jean-Luc Gaudiot 《International journal of parallel programming》2008,36(4):361-385
By executing two or more threads concurrently, Simultaneous MultiThreading (SMT) architectures are able to exploit both Instruction-Level
Parallelism (ILP) and Thread-Level Parallelism (TLP) from the increased number of in-flight instructions that are fetched
from multiple threads. However, due to incorrect control speculations, a significant number of these in-flight instructions
are discarded from the pipelines of SMT processors (which is a direct consequence of these pipelines getting wider and deeper).
Although increasing the accuracy of branch predictors may reduce the number of instructions so discarded from the pipelines,
the prediction accuracy cannot be easily scaled up since aggressive branch prediction schemes strongly depend on the particular
predictability inherently to the application programs. In this paper, we present an efficient thread scheduling mechanism
for SMT processors, called SAFE-T (Speculation-Aware Front-End Throttling): it is easy to implement and allows an SMT processor
to selectively perform speculative execution of threads according to the confidence level on branch predictions, hence preventing
wrong-path instructions from being fetched. SAFE-T provides an average reduction of 57.9% in the number of discarded instructions
and improves the instructions per cycle (IPC) performance by 14.7% on average over the ICOUNT policy across the multi-programmed
workloads we simulate.
This paper is an extended version of the paper, “Speculation Control for Simultaneous Multithreading,” which appeared in the
Proceedings of the 18th International Parallel and Distributed Processing Symposium, Santa Fe, New Mexico, April 2004. 相似文献
132.
XinLong Huang Gang Liu Xiong Ying Jun Wang Yuhua Guo Chunlei Kang Yangchao Tian 《Microsystem Technologies》2008,14(9-11):1257-1261
Sacrificial-Layer technology is widely used in the microfabrication field of SLIGA. In this paper, thick sacrificial layers of zinc techniques are studied. A movable structure with aspect ratio of 25 has been fabricated by using zinc sacrificial layer through LIGA technique. Compared with conventional metal sacrificial layers of titanium or copper, the thickness of zinc layer can grow up to more than 10 μm. The adhesion of different seed layers and the physiognomy of sacrificial layer are also focused in this paper. 相似文献
133.
针对模糊控制表达能力强,但学习能力、适应性差的特点,提出在聚合釜温度控制过程中使用模糊控制与神经网络相结合的控制方案.给出了神经模糊网络结构和学习算法,仿真研究表明,神经模糊网络可以直接从经验中获取知识,自动建立模糊规则和隶属函数,无需查表,具有较强的适应和联想能力,比单纯的模糊控制具有更大的优势. 相似文献
134.
流行的Segmenter分词算法是开放的java源代码,它是一个很好的分词工具。但是,在全文检索系统中对分词有特殊的要求,例如歧义包客、专业词典等。所以在这里将Segmenter词典和算法都进行了改选,建立了树状词典,在匹配算法中使用了歧义包容法则、分支处理、动态规划和词库预载入。以适应电子商务案例全文检索系统。 相似文献
135.
LiQiang Zhang ZhiFeng Guo ZhiZhong Kang LiXin Zhang XingMing Zhang Ling Yang 《中国科学F辑(英文版)》2009,52(9):1588-1597
Adaptive rendering large and complex spatial data has become an important research issue in a 3DGIS application. In order to transmit the data to the client efficiently,this paper proposes a node-layer data model to manage the 3D scene. Because the large spatial data and limited network bandwidth are the main bottlenecks of web-based 3DGIS,a client/server architecture including progressive transmission methods and multiresolution representations,together with the spatial index,are developed to improve the p... 相似文献
136.
137.
Graph drawing and visualization represent structural information as diagrams of abstract graphs and networks. An important subset of graphs is directed acyclic graphs (DAGs). This paper presents a new E-Spring algorithm, extended from the popular spring embedder model, which eliminates node overlaps in clustered DAGs. In this framework, nodes are modeled as non-uniform charged particles with weights, and a final drawing is derived by adjusting the positions of the nodes according to a combination of spring forces and repulsive forces derived from electrostatic forces between the nodes. The drawing process needs to reach a stable state when the average distances of separation between nodes are near optimal. We introduce a stopping condition for such a stable state, which reduces equilibrium distances between nodes and therefore results in a significantly reduced area for DAG visualization. It imposes an upper bound on the repulsive forces between nodes based on graph geometry. The algorithm employs node interleaving to eliminate any residual node overlaps. These new techniques have been validated by visualizing eBay buyer–seller relationships and has resulted in overall area reductions in the range of 45–79%. 相似文献
138.
Youn‐Gyoung Chang Seong‐Hee Nam Nam‐Kook Kim Yun‐Ho Kook Jinook Kim Soon‐Sung Yoo Chang‐Dong Kim In‐Byeong Kang In‐Jae Chung 《Journal of the Society for Information Display》2009,17(4):301-307
Abstract— Recently, potential breakthrough technologies for low‐cost processing of TFT‐LCDs and new process developments for flexible‐display fabrication have been widely studied. A roll‐printing process using etch‐resist material as a replacement for photolithographic patterning was investigated. The characterization of the properties of patterns formed in roll printing, a method to fabricate cliché plates for fine patterns, and the design of a new formulation for resist printing ink is reported. The pattern position accuracy, which is one of the most important issues for the successful application of printing processes in display manufacturing was studied and how it can be improved by optimizing the blanket roll structure is explained. New design rules for the layout of the thin‐film‐transistor array was derived to improve the compatibility of roll printing. As a result, a prototype 15‐in.‐XGA TFT‐LCD panel was fabricated by using printing processes to replace all the photolithographic patterning steps conventionally used. 相似文献
139.
The maximum entropy principle (MEP) is used to generate a natural probability distribution among the many possible that have
the same moment conditions. The MEP can accommodate higher order moment information and therefore facilitate a higher quality
PDF model. The performance of the MEP for PDF estimation is studied by using more than four moments. For the case with four
moments, the results are compared with those by the Pearson system. It is observed that as accommodating higher order moment,
the estimated PDF converges to the original one. A sensitivity analysis formulation of the failure probability based on the
MEP is derived for reliability-based design optimization (RBDO) and the accuracy is compared with that by finite difference
method (FDM). Two RBDO examples including a realistic three-dimensional wing design are solved by using the derived sensitivity
formula and the MEP-based moment method. The results are compared with other methods such as TR-SQP, FAMM + Pearson system,
FFMM + Pearson system in terms of accuracy and efficiency. It is also shown that an improvement in the accuracy by including
more moment terms can increase numerical efficiency of optimization for the three-dimensional wing design. The moment method
equipped with the MEP is found flexible and well adoptable for reliability analysis and design. 相似文献
140.
军事Web信息系统要求用户权限必须严格控制、统一管理、维护简便.基于RBAC的访问控制模型能有效弥补DAC和MAC的不足.针对著名的RBAC96模型的缺陷,提出数据资源以业务功能表示、预设角色与用户临时权限的改进角色权限控制模型.该改进方法已经在某军事Web信息系统中得到了应用. 相似文献