检索结果-内蒙古大学图书馆

2011 7th International Conference on Mobile Ad-hoc and Sensor Networks, MSN 2011

作者： Lu, Huang Li, Jie Dong, Zhongping Ji, Yusheng Department of Computer Science University of Tsukuba Tsukuba Science City Japan Information Systems Architecture Science Research Div. National Institute of Informatics Tokyo Japan

ISBN: (纸本)9780769546100

Directional antennas in wireless ad hoc networks (WANETs) offer great potential to reduce the radio interference, and improve the communication throughput. Using directional antennas, however, introduces a new problem in the wireless media access control (MAC), deafness, which may cause severe performance degradation. To solve the deafness problem, in this paper, we propose a novel CRDMAC protocol by using a sub-transmission channel and RTR (Ready To Receive) packets, which modifies the IEEE 802.11 distributed coordinated function. The sub-channel avoids collisions to other ongoing transmission and the RTR packets notify the neighbors that the mutual transmission has finished. The proposed MAC protocol decreases the binary exponential back off time of the waiting nodes. We evaluate our protocol through simulations. Simulation results show that the proposed protocol outperforms the existing DMAC (directional MAC) protocol and the CRCM (Circular RTS and CTS MAC) protocol in terms of throughput and packet drop rate. © 2011 IEEE.

关键词： Medium access control

来源：评论

学校读者我要写书评

暂无评论

Context-aware energy management for energy-self-sufficient network nodes in wireless mesh networks

Context-aware energy management for energy-self-sufficient n...

引用

International Conference on Ultra Modern Telecommunications and Workshops (ICUMT)

作者： Alexander Gladisch Robil Daher Philipp Lehsten Djamshid Tavangarian Computer Architecture Institute of Computer Science University of Rostock Germany

Wireless Mesh Networks (WMNs) are increasingly applied for various applications. Many advantages of WMNs are based on the autonomous operation of the mesh nodes. A main factor to achieve autonomy is energy-self-sufficiency. Here, the usage of renewable energy generators combined with energy storages is a common approach. However, an efficient mechanism is needed to manage the constrained energy resources as well as the amount of generated energy. Therefore, we propose in this paper a context-aware energy management system (CA-EMS) for energy-self-sufficient network nodes. In our CA-EMS, we determine an energy budget on basis of energy generation, energy consumption and available context information. Furthermore, we classify the available context, and we define context-based rules and actions to keep the energy budget of the nodes in balance. Our use case, that is a real-world system, shows more practically, that applying CA-EMS prolongs the runtime of the mesh node while keeping the energy budget in balance.

关键词： Energy consumption Energy management Context Manganese Energy storage computers Generators

来源：评论

学校读者我要写书评

暂无评论

New image de-noising method using Curvelet transform

New image de-noising method using Curvelet transform

引用

2011 International Conference on Consumer Electronics, Communications and Networks, CECNet 2011

作者： Ji, Jing Gai, Shan School of Mechanical and Electrical Engineering Anhui University of Architecture Anhui China School of Computer Science and Technology Harbin Institute of Technology Harbin China

ISBN: (纸本)9781612844572

The image de-noising method via USFFT Curvelet transform is proposed in this paper. The method can preserve the detail information of high frequency of noisy image, and to avoid the phenomenon of edge slant during the image reconstruction. The USFFT Curvelet transform is used to the noisy image, the global threshold value is estimated in the Curvelet domain. The window technique is used to compute the shrinkage factor corresponding to pixel value. The de-noised image signal is obtained by using inverse USFFT Curvelet transform. The experimental results show that the algorithm obtains a higher PSNR value for gray and color images. It acquires a good de-noisy effect and visual effect, and preserves image edge well. © 2011 IEEE.

关键词： Wavelet transforms

来源：评论

学校读者我要写书评

暂无评论

33 High-resolution cryo-EM structure of theTrypanosoma brucei80S: a unique eukaryotic ribosome

引用

Journal of Biomolecular Structure and Dynamics 2013年第SUPP 1期31卷 20页

作者： Amy Jobe[a][*] Yaser Hashem[a] Amedee des Georges[a] Jie Fu[b] Sarah N. Buss[c] Fabrice Jossinet[d] Qin Zhang[e] Hstau Y. Liao[b] Bob Grassucci[c] Chandrajit Bajaj[e] Susan Madison-Antenucci[c] Eric Westhof[d] & Joachim Frank[a][b][f] [a] HHMI Department of Biochemistry and Molecular Biophysics Columbia University New York NY USA [b] Department of Biochemistry and Molecular Biophysics Columbia University New York NY USA [c] Division of Infectious Diseases Wadsworth Center New York State Department of Health Albany NY USA [d] Architecture et Réactivité de l’ARN Université de Strasbourg Institut de Biologie Moléculaire et Cellulaire (CNRS) Strasbourg France [e] Department of Computer Science Institute for Computational Engineering and Sciences University of Texas Austin TX USA [f] Department of Biological Sciences Columbia University New York NY USA

Eukaryotic 80S ribosomes of known structure are far more complex than their 70S bacterial counterparts. Those fromSaccharomyces cerevisiae,Tetrahymena thermophila, andTriticum aestivum, for example, bear insertions of ribosomal RNA (rRNA) called expansion segments (ES) and additional ribosomal proteins. The ribosomes of the kinetoplastidTrypanosoma brucei, though, are especially fascinating: structurally and their other kinetoplastids’ ribosomes bear very large ESs, as well as smaller ESs, and protein extensions. Additionally,T. bruceiribosomes require novel protein factors for maturation, although they do not require several eukaryotic initiation factors or a recycling factor. As a species,T. bruceiis fascinating not only in terms of structure, but also in terms of gene expression and even public health: the species is responsible for the incurable, terminal human African Trypanosomiasis (sleeping sickness); and during post-transcriptional regulation, a single common RNA segment called a splice leader is trans-spliced onto the 5′ ends of many ofT. brucei’s mRNAs. The purpose of this splice event in translation is unknown. Here, we present a high-resolution structure of theT. bruceiribosome which contributes a great deal to addressing the above unknowns. We have employed map segmentation, homology modeling, ab initio rRNA modeling, and Molecular Dynamics Flexible Fitting (MDFF) to model the ribosome’s atomic structure. The positions and structures of the ribosome’s novel ESs and protein extensions were previously unknown, but our structure reveals the precise spatial contexts of these components. With this information in hand, we can begin to decipherT. brucei’s unusual translational requirements.

关键词：

来源：评论

学校读者我要写书评

暂无评论

An ultra-fast hybrid simulation framework for ASIP

An ultra-fast hybrid simulation framework for ASIP

引用

2011 18th IEEE International Conference on Electronics, Circuits and Systems, ICECS 2011

作者： Qiu, Ji Gao, Xiang Jiang, Yifei Xiao, Xu Key Laboratory of Computer System and Architecture Institute of Computing Technology Graduate University of Chinese Academy of Science Beijing 100190 China Department of Electrical and Computer Engineering University of Illinois at Urbana-Champaign Urbana IL United States

ISBN: (纸本)9781457718458

ISS (Instruction Set Simulator) plays an important role in pre-silicon software development for ASIP. However, the speed of traditional simulation is too slow to effectively support full-scale software development. In this paper, we propose a hybrid simulation framework which further improves the previous simulation methods by aggressively utilizing the host machine resources. The utilization is achieved by categorizing instructions of ASIP application into two types, namely custom and basic instructions, via binary instrumentation. Then in a way of hybrid simulation, only custom instructions are simulated on the ISS and basic instructions are executed fast and natively on the host machine. We implement this framework for an industrial ASIP to validate our approach. Experimental results show that when the implemented ISS, namely GS-Sim, is applied to practical multimedia decoders, an average simulation speed up to 1058.5MIPS can be achieved, which is 34.7 times of the state-of-art dynamic binary translation simulator and is the fastest to the best of our knowledge. © 2011 IEEE.

关键词： Software design

来源：评论

学校读者我要写书评

暂无评论

Performance comparison of designated preprocessing white light interferometry algorithms on emerging multi- and many-core architectures

引用

Procedia computer science 2011年 4卷 2037-2046页

作者： Max Schneider Dietmar Fey Daniel Kapusi Torsten Machleidt Chair of Computer Science 3 (Computer Architecture) Friedrich-Alexander-University of Erlangen-Nuremberg ZBS e.V. Ilmenau Computer Graphics Group Technical University of Ilmenau GBS mbH Ilmenau

Parallel computing has been a niche for scientific research in academia for decades. However, as common industrial applications become more and more performance demanding and raising the clock frequency of conventional single-core systems is hardly an option due to reaching technological limitations, efficient use of multi-core CPUs has become imperative. 3D surface analysis of objects using the white light interferometry presents one of such computationally challenging applications. In this article three established preprocessing methods of white light interferometry data analysis are used to evaluate the suitability of three modern multi-core architectures - generic multi-core CPUs, GPGPUs and IBM's Cell BE. The results show that function offloading to GPGPUs, which offer independent memory and many hundreds of threads running in parallel, yields the highest performance compared to other systems. Furthermore, by outsourcing computational tasks to GPUs, the workload of other system resources, such as CPU or system memory, is reduced. This allows accelerated execution of other tasks, e.g. acquisition of images with higher frame rates.

关键词： White light interferometry Preprocessing Algorithms OpenMP IBM Cell BE CUDA GPGPU

来源：评论

学校读者我要写书评

暂无评论

Optimizing web browser on many-core architectures

Optimizing web browser on many-core architectures

引用

2011 12th International Conference on Parallel and Distributed Computing, Applications and Technologies, PDCAT 2011

作者： Fan, Lingjun Shi, Weisong Tang, Shibin Yan, Chenggang Fan, Dongrui Key Laboratory of Computer System and Architecture Institute of Computing Technology Chinese Academy of Sciences Beijing China Academy of Sciences Graduate University Beijing China Department of Computer Science Wayne State University Detroit United States

ISBN: (纸本)9780769545646

As more and more Web applications emerging on sever end today, the Web browser on client end has become a host of a variety of applications other than just rendering static Web pages. This leads to more and more performance requirements of a Web browser, for which user experience is very important. This situation may become more urgency when on handheld devices. Some efforts like redesign a new Web browser have been made to overcome this problem. In this paper, we address this issue by optimizing the main processes of the Web browser on a state-of-the-art 64-core architecture, Godson-T, which was developed at Chinese Academy of sciences, as multi-/many-core architecture to be the mainstream processor in the upcoming years. We start a new core to process a new tab when facing up to intensive URL requests, and we use scratch-pad memory (SPM) of each core as a local buffer to store the HTML source data to be processed to reduce off-chip memory access and exploit more data locality, otherwise, we use DTA to transfer HTML data for backup. Experiments conducted on the cycle-accurate simulator show that, starting each tab process by a new core could obtain 5.7% to 50% speedup with different number of cores used to process corresponding URL requests, with onchip scratchpad memory of each core used to store the HTML data, more speedup could be achieved when number of cores increase. Also, as Data Transfer Agent (DTA) used to transfer the HTML data, the backup of HTML data can get 2X to 5X speedups according to different data amount. © 2011 IEEE.

关键词： Data transfer

来源：评论

学校读者我要写书评

暂无评论

Robust embedded software design through early analysis of quality faults 11

Robust embedded software design through early analysis of qu...

引用

Proceedings of the 4th India Software Engineering Conference

作者： Das, Dipankar Chakrabarti, P.P. Sinha, Purnendu Electrical and Software Architecture Group GM India Science Lab. Bangalore 560066 India Department of Computer Science and Engineering Indian Institute of Technology Kharagpur Kharagpur 721302 India

ISBN: (纸本)9781450305594

While providing correct functionality has been the thrust of most software design efforts, embedded software poses several additional challenges. Among them is designing robust software which can tolerate inaccurate inputs (coming from degraded sensors), failure of software components, and wearing-out of electro-mechanical parts it controls. For this, a design space exploration is performed and several design options are evaluated for their ability to tolerate quality (or accuracy degradation) faults. While a model-based approach enables an early analysis of quality faults, modeling and analyzing the effects of quality faults is a challenge. In this work we propose a quality fault-tolerance analysis framework which is used on operation-level models of embedded software, and an abstraction of quality-faults suitable for this analysis. The proposed method consists of characterizing individual components of the model, and then using the pre-characterized behaviors to quickly evaluate the software design. Characterization is a one-time effort and results of the same can be reused when a new design is evaluated. This results in additional speedup of upto 6-10× faster evaluation of designs, thereby facilitating a quick early evaluation of design options.

关键词： Software design

来源：评论

学校读者我要写书评

暂无评论

Social attribute based web service information publication mechanism in delay tolerant network

Social attribute based web service information publication m...

引用

14th IEEE Int. Conf. on Computational science and Engineering, CSE 2011, the 11th International Symposium on Pervasive Systems, Algorithms, and Networks, I-SPAN 2011, and the 10th IEEE Int. Conf. on Ubiquitous Computing and Communications, IUCC 2011

作者： Cao, Jiuxin Yang, Liu Zheng, Xiao Liu, Bo Zhao, Lei Ni, Xudong Dong, Fang Mao, Bo Southeast University School of Computer Science and Engineering Nanjing China Royal Institute of Technology School of Architecture and the Built Environment Stockholm SE-100 44 Sweden

ISBN: (纸本)9780769544779

The intermittence of the connection between nodes and limited resources greatly impair the effectiveness of service information publication in Delay Tolerant Network (DTN). To overcome this problem, a multi-layer service information cooperative publication mechanism is proposed in this paper. Firstly, the social interaction network and service overlay network is established in the form of abstract weight graph. Then, the community division algorithm is used to analysis the social characteristics of service interaction and the social attribute based DTN model-S-DTN is constructed. Finally, the carrier nodes of the information publication is selected from neighbor set by computing utilization function based node context, and a multi-layer cooperative mechanism is proposed to achieve effective service information publication in DTN. The experiment results indicate that the proposed publication mechanism brings nearly the same success ratio as Epidemic Routing with lower delay and network loads. Additionally, it shows better performance in overall metrics than Prophet Routing. © 2011 IEEE.

关键词： Delay tolerant networks

来源：评论

学校读者我要写书评

暂无评论

A model for assessing the degree of formalization and support of learning scenarios

A model for assessing the degree of formalization and suppor...

引用

International Conference on Interactive Collaborative Learning (ICL)

作者： Mario Donick Christian Schönfeldt Anja Thomanek Djamshid Tavangarian Research Group Computer Architecture Institute of Computer Science University of Rostock Rostock Germany

Technical developments and a more flexible relation between working and private life lead to the inclusion of both formal and informal aspects in learning concepts, as well as supported and unsupported phases, with a flexible role of learners, tutors, and teachers. While formal and non-formal learning is mostly carried out in instructional programs, informal learning takes place in everyday life situations [10]. The complexity of learning concepts with different degrees of formalization and support can cause difficulties in the preparation, because didactical and methodical decisions have to be made where, when, and how learners, tutors, and teachers should work together. Thus, in this paper we present a structured approach for categorizing learning scenarios, fields, and activities on the two dimensions formalization (formal/informal) and support (supported/unsupported). The examples of Media-based Junior Studies (MbJS) and DAAD project “IT, Culture, and Gender” - both projects with very heterogeneous learners and contents - show that the suggested dimensions are useful in the preparation of these learning concepts.

关键词： Educational institutions Cultural differences Conferences Communities Qualifications Collaborative work

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：