ppxscal/embedding_network huggingface dataset:
DDoS Detection and Traceback with Decision Tree and Grey Relational Analysis
Authors: Yi-Chi Wu, Huei-Ru Tseng, Wuu Yang, Rong-Hong Jan
Venue: Proceedings of the 2009 Third International Conference on Multimedia and Ubiquitous Engineering (2009)

As modern life becomes increasingly closely bound to the Internet, network security becomes increasingly important. Like it or not, we all live under the shadow of network threats. The threats could cause leakage of privacy and/or economic loss. Among network attacks, the DDoS (distributed denial-of-service) attack is one of the most frequent and serious. In a DDoS attack, an attacker first breaks into many innocent computers (called zombies) by taking advantages of known or unknown bugs and vulnerabilities in the software. Then the attacker sends a large number of packets from these already-captured zombies to a server. These packets either occupy a major portion of the server's network bandwidth or they consume much of theserver's time. The server is then prevented from conducting normal business operations.In order to mitigate the DDoS threat, we design a system to detect DDoS attacks based on a decision-tree techniqueand, after detecting an attack, to trace back to the approximate locations of the attacker with a traffic-flow pattern-matching technique. We conduct our experiment on the DETER system. According to our experiment results, our system could detect the DDoS attack with the false positive ratio about 1.2% - 2.4%, false negative ratio about 2% - 10% with different kind of attack, attack sending rate and find the attack path in trace back withthe false negative rate 8% - 12% and false positive rate 12% - 14%. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
Traffic Modeling with Bernoulli Shift Map
Authors: Fei Ge, Liansheng Tan, Yuanni Wang
Venue: Proceedings of the 2009 Fifth International Joint Conference on INC, IMS and IDC (2009)

Statistical properties of Internet traffic are complex and we apply Bernoulli shift map to generate packet traffic. The packet producing time is dependent on evaluation of Bernoulli shift map, which is a different mechanism from ON/OFF mechanism, called Time Bernoulli Shift (TBS). Packet traffic from TBS has a convergent average rate after enough iteration, inherent self similarity characteristic and chaotic characteristic which can be adjusted by parameters of Bernoulli shift map.
Asymptotic BEP and SEP of quadratic diversity combining receivers in correlated ricean fading, non-Gaussian noise, and interference
Authors: Ali Nezampour, Amir Nasri, Robert Schober, Yao Ma
Venue: IEEE Transactions on Communications (2009)

In this paper, we study the asymptotic behavior of the bit-error probability (BEP) and the symbol-error probability (SEP) of quadratic diversity combining schemes such as coherent maximum-ratio combining (MRC), differential equal-gain combining (EGC), and noncoherent combining (NC) in correlated Ricean fading and non-Gaussian noise, which in our definition also includes interference. We provide simple and easy-to-evaluate asymptotic BEP and SEP expressions which show that at high signal-to-noise ratios (SNRs) the performance of the considered combining schemes depends on certain moments of the noise and interference impairing the transmission. We derive general rules for calculation of these moments and we provide closed-form expressions for the moments of several practically important types of noise such as spatially dependent and spatially independent Gaussian mixture noise, correlated synchronous and asynchronous co-channel interference, and correlated Gaussian interference. From our asymptotic results we conclude that (a) the asymptotic performance loss of binary frequency-shift keying (BFSK) with NC compared to binary phase-shift keying (BPSK) withMRC is always 6 dB independent of the type of noise and the number of diversity branches, (b) the asymptotic performance loss of differential EGC compared to MRC is always 3 dB for additive white Gaussian noise but depends on the number of diversity branches and may be larger or smaller than 3 dB for other types of noise, and (c) not only fading correlation but also noise correlation negatively affects the performance of quadratic diversity combiners.
Shannon-Kotel'nikov mappings in joint source-channel coding
Authors: Fredrik Hekland, Pål Anders Floor, Tor A. Ramstad
Venue: IEEE Transactions on Communications (2009)

This paper deals with lossy joint source-channel coding for transmitting memoryless sources over AWGN channels. The scheme is based on the geometrical interpretation of communication by Kotel'nikov and Shannon where amplitude-continuous, time-discrete source samples are mapped directly onto the channel using curves or planes. The source and channel spaces can have different dimensions and thereby achieving either compression or error control, depending on whether the source bandwidth is smaller or larger than the channel bandwidth. We present a general theory for 1:N and M:1 dimension changing mappings, and provide two examples for a Gaussian source and channel where we optimize both a 2:1 bandwidth-reducing and a 1:2 bandwidth-expanding mapping. Both examples show high spectral efficiency and provide both graceful degradation and improvement for imperfect channel state information at the transmitter.
Capacity region of the linear four-node half-duplex wireless relay network
Authors: Chi Wan Sung, Qi Wang, Kenneth W. Shum
Venue: IEEE Communications Letters (2009)

A three-phase transmission scheme for the linear four-node half-duplex wireless relay network is proposed. In each of its two cooperative phases, the setting is equivalent to the broadcast channel with cognitive receiver, whose capacity region is determined. Based on that result, the three-phase scheme is shown to be capacity achieving. Its performance is compared with two suboptimal schemes.
An Efficient Coding of Intra Picture Prediction Modes for H.264/AVC
Authors: Jie Jia, Daeil Yoon, Hae Kwang Kim
Venue: Proceedings of the 2009 Third International Conference on Multimedia and Ubiquitous Engineering (2009)

Video coding standard H.264/AVC employs nine-mode directional spatial prediction for intra picture coding. It predicts pixels to be encoded from previously decoded neighboring pixels within current picture. This paper presents an efficient coding method for H.264 intra picture prediction modes to enhance coding efficiency performance. The proposed method improves prediction of intra picture most probable mode (MPM), and applies Huffman coding to encode MPM pattern for every four 4x4 blocks. In addition, a combined intra picture prediction mode is discussed. Simulation results report that the proposed method yields an average of 1.28% bit rate reduction over the H.264 baseline profile. The ACM Portal is published by the Association for Computing Machinery. Copyright © 2010 ACM, Inc. Terms of Usage Privacy Policy Code of Ethics Contact Us Useful downloads: Adobe Acrobat QuickTime Windows Media Player Real Player
A high-performance and energy-efficient TCAM design for IP-address lookup
Authors: Yen-Jen Chang
Venue: IEEE Transactions on Circuits and Systems II: Express Briefs (2009)

In this brief, we propose a two-level don't-care gating (DCG) scheme that aims to reduce the ternary content-addressable memory (TCAM) power dissipated in the search-line switching activity. By exploiting the vertically continuous "don't-care" feature, the two-level DCG scheme can largely reduce the average search-line power consumption during a switch pattern. In addition, we also use the search enable technique to eliminate the unnecessary search-line switching activity in the quiet pattern. By reducing both the search-line switching activity and average switching power, the proposed design can minimize the TCAM search-line power consumption. For a 128 × 32 TCAM, the best configuration We examined shows that when the first-level and second-level gating granularities are 16 and 8, respectively, with a 9% search performance improvement, the two-level DCG scheme can achieve 70% search-line energy reduction.
Cutting planes and beyond
Authors: Michael Clifton, Alex Pang
Venue: Computers and Graphics (1997)

We present extensions to the traditional cutting plane that become practical with the availability of virtual reality devices. These extensions take advantage of the intuitive ease of use associated with the cutting metaphor. Using their hands as the cutting tool, users interact directly with the data to generate arbitrarily oriented planar surfaces, linear surfaces, and curved surfaces. We find that this type of interaction is particularly suited for exploratory scientific visualization where features need to be quickly identified and precise positioning is not required. We also document our investigation on other intuitive metaphors for use with scientific visualization.
e-learning from the technical university students point of view
Authors: Alena Vališová, Jiří Šubrt, Pavel Andres
Venue: Proceedings of the 10th IASTED International Conference on Computers and Advanced Technology in Education (2007)

The Dpt. of Engineering Pedagogy, Masaryk Institute of Advanced Studies (MIAS), CTU in Prague prepares students for the profession of technical teacher in the Bachelor study program "Technical Teacher Education". At the Dpt. of Engineering Pedagogy, we carried out an investigation focused on the students' opinions and views on the modern teaching tools and how they perceive the concept of e-learning. For this purpose, 68 freshman students both in-class and distance form of study were asked to write an essay the goal of which was to identify the previous experience of the respondents, educational benefits, shortcomings, and to define their conception of possible future development at our department. We are interested in students' opinions continuously, of course, so as to have very important feedback of the quality of education. Besides results that will be presented, we performed some exploratory studies recently. They were focused especially on the questionnaire survey discussing the benefits of model teaching presentation as a method of role playing, quality of videos as a teaching aid (a project called "Representative classes") and efficiency of work with these videos in the seminars during the subject Teaching Methodology, etc. We have still been collecting valuable information that can be helpful for improving the quality of technical teacher education.
A web enhanced calling-the-roll support system
Authors: Chao Zeng
Venue: Proceedings of the 10th IASTED International Conference on Computers and Advanced Technology in Education (2007)

This paper presents the development of a system which supports teacher to manage his/her students' studying information including records of attendance for every student and their examination results. For teacher, in order to grasp every student's studying situation, calling the roll is an old but important means to help achieve the purpose. In our system teacher's activity of calling the roll is strongly supported by adding some multimedia data such as student's face photo to be shown in the process of calling the roll. The system manages attendance data up to now and shows statistics compiled from the data to teacher's window when a new calling the roll is under execution. The digitized records of student's attendance can be easily and rapidly shared with the college administration office and related teachers and then timely measures can be taken to deal with the student's studying troubles.
A geometric approach for turbo decoding of Reed-Solomon codes in QAM modulation schemes
Authors: Cristhof J. Roosen Runge, José Roberto C. Piqueira
Venue: IEEE Communications Letters (2009)

This work studies the turbo decoding of Reed-Solomon codes in QAM modulation schemes for additive white Gaussian noise channels (AWGN) by using a geometric approach. Considering the relations between the Galois field elements of the Reed-Solomon code and the symbols combined with their geometric dispositions in the QAM constellation, a turbo decoding algorithm, based on the work of Chase and Pyndiah, is developed. Simulation results show that the performance achieved is similar to the one obtained with the pragmatic approach with binary decomposition and analysis.
Financial valuation in the banking industry
Authors: C. H. Fouche, M. A. Petersen, J. Mukuddem-Petersen
Venue: Proceedings of the Fourth IASTED International Conference on Financial Engineering and Applications (2007)

Our aim is do a bank valuation by considering its cash flow that is, in turn, calculated via banking profit and depreciation. The Basel II capital accord permits a modeling approach to capital adequacy, by which banks are allowed to use their internal Value-at-Risk (VaR) models to help determine their capital requirements. In this regard, we investigate a risk model for the value of a bank that is able to invest in loans and Treasuries. The loan price process and the total depreciation is modeled via an exponential L&eacute;vy process and a compound Poisson process, respectively. These models lead to the formulation of a bank value maximization problem subject to a risk constraint on the VaR. Our investigation concludes with a brief analysis of the main banking valuation issues.
Face recognition under occlusions and variant expressions with partial similarity
Authors: Xiaoyang Tan, Songcan Chen, Zhi-Hua Zhou, Jun Liu
Venue: IEEE Transactions on Information Forensics and Security (2009)

Recognition in uncontrolled situations is one of the most important bottlenecks for practical face recognition systems. In particular, few researchers have addressed the challenge to recognize noncooperative or even uncooperative subjects who try to cheat the recognition system by deliberately changing their facial appearance through such tricks as variant expressions or disguise (e.g., by partial occlusions). This paper addresses these problems within the framework of similarity matching. A novel perceptionin-spired nonmetric partial similarity measure is introduced, which is potentially useful in dealing with the concerned problems because it can help capture the prominent partial similarities that are dominant in human perception. Two methods, based on the general golden section rule and the maximum margin criterion, respectively, are proposed to automatically set the similarity threshold. The effectiveness of the proposed method in handling large expressions, partial occlusions, and other distortions is demonstrated on several well-known face databases.
Towards deeper learning through creativity within online communities in primary education
Authors: Keith Turvey
Venue: Computers Education (2006)

Despite recent British government moves to equip all Primary Schools with fast broadband connections to the Internet, it would seem that many schools as yet make little use of the increased capacity this affords other than to incorporate more and more rich multimedia in the form of interactive games or animated presentations to illustrate particular concepts or practise specific skills. Whilst not wanting to deny the potential and value of such activities, this paper will focus on the potential use of online communities to reverse this rather unidirectional relationship children often experience with the Internet. That is, the potential within online communities to facilitate a more reciprocal relationship as children become benefactors as well as recipients of the wealth of web-based information, and the quality of learning that may ensue. A small-scale comparative case study was undertaken in two Primary Schools where children were given access to online tools allowing them to communicate and participate - in and out of school - within an online community. Methodological tools used included content analysis of children's websites and semi-structured interviews with the students and their teachers. The type of learning that online communities may yield, I will argue, is one that is based upon a deep understanding of what it means to both be a learner, and to take responsibility for one's learning. Furthermore, the findings appear to imply that the participation and role played by the teacher within the virtual community is vital to the quality of learning.
Formal modeling and verification of shop floor controller logics
Authors: Devinder Thapa, C. M. Park, S. C. Park, Gi-Nam Wang
Venue: Proceedings of the IASTED Asian Conference on Modelling and Simulation (2007)

In this paper, we proposed an approach to formally model, and verify the shop floor controller logics. The verification process starts with modeling the targeted system using t-MPSG (an extended communicating finite state automaton). Thereafter, textual format of the t-MPSG is translated to native code of model checker, SMV. Afterwards, it can be combined with temporal logic to describe the required properties. Finally, model checking tool automatically verifies the model of the shop floor controller logic as per specified properties. In case of failure to satisfy the given properties, it produces counter examples. An illustration of the formal modeling and verification process is presented, in this paper, to clarify the approach, with a suitable example of shop floor control system.
Performance Evaluation of Real-Time Indoor Positioning with Active-RFID and CSS-Based Nano Lock System
Authors: Allen Y. Chang, Dwen-Ren Tsai, Tsung-Chi Liu, Chun-Jung Chen, I-Horng Jeng
Venue: Proceedings of the 2009 Fifth International Joint Conference on INC, IMS and IDC (2009)

Various indoor positioning methods have been proposed both in theory and practice. Each method has different degree of accuracy. Due to the smaller indoor venues, the torrent for error is also smaller. Therefore, indoor positioning system requires more precise measurement than outdoor. We use active RFID and real-time nano-precision positioning devices to assess the feasibility of indoor positioning system. This study is to conduct experimental study of the distance measure using RSSI and TDOA, and analysis the experimental results.
The problem arena of researching computer supported collaborative learning: Introduction to the special section
Authors: Martin Valcke, Rob Martens
Venue: Computers Education (2006)

In this introduction to the special section, research in relation to asynchronous discussions in computer supported collaborative learning (CSCL) environments is analysed from a methodological perspective. The discussion centres on three quality issues that are considered as critical in recent content analysis approaches: (1) the accuracy of the research methodology applied to gather data in CSCL-settings, (2) the low reliability of the research instruments and procedures, and (3) questions about the validity of the research instruments. Finally, the four contributions in the special are positioned in relation to these three critical topics.
An enhanced cooperative spectrum sensing scheme based on evidence theory and reliability source evaluation in cognitive radio context
Authors: Nhan Nguyen-Thanh, Insoo Koo
Venue: IEEE Communications Letters (2009)

This letter proposes an enhanced scheme for co-operative spectrum sensing which utilizes the signal to noise ratios to evaluate the degree of reliability of each local spectrum sensing terminal on a distributed Cognitive Radio network. The terminals' reliability weight is applied to adjust its sensing data more accuratly before making fusion by Dempter-Shafer theory of evidence. Simulation results show that significant improvement of the cooperative spectrum sensing gain is achieved by our scheme.
Proceedings of the 1st ACM International Workshop on Hot Topics of Planet-Scale Mobility Measurements
Venue: International Conference On Mobile Systems, Applications And Services (2009)

It is well-known that successfully researching, designing and building mobile systems and algorithms requires access to large-scale mobility data. Unfortunately, the wireless and mobile research communities lack such data. For instance, the largest publicly available human contact traces contain only 100 very sparsely connected nodes, a limitation of the experimental setup. We believe that large-scale datasets are important, not only in communication network design, but also for fundamental study in other academic disciplines, e.g., epidemiology, urban planning, and social science. An analogy can be made to the field of complex networks research, which flourished since 1989 when the first large datasets from the Internet (and subsequently the World Wide Web) became available. To achieve similar improvements in mobile networking and other related fields, relevant large-scale datasets must be made available.
Risk Assessment of Thermal Power Plant Project Based on Fuzzy Analytic Hierarchy Process in the Early Operation
Authors: Duan Lidong, Niu Dongxiao, Lv Haitao, Kou Bingen
Venue: Proceedings of the 2009 Second International Workshop on Computer Science and Engineering - Volume 01 (2009)

As the development of technology, the enterprises of our country have came into the stage of all-round risk management. But there are still many problems in the initial stage of risk management about thermal power plant projects. This paper brings forward the concept of initial risk evaluation about constructive projects in thermal power plant, puts forward and builds the evaluation index system for the first time. Besides we develop traditional Analytic Hierarchy Process(AHP) using triangular fuzzy numbers according to the subjective fuzziness of experts’ judging, so to solve the weight of index in each level. Integrated with the idiographic thermal power units, the risk level of the thermal project is evaluated according to the membership degree of risk.
A CMOS ultra low-power and highly efficient UWB-IR transmitter for WPAN applications
Authors: Shengxi Diao, Yuanjin Zheng, Chun-Huat Heng
Venue: IEEE Transactions on Circuits and Systems II: Express Briefs (2009)

This brief presents an on-off LC oscillator-based ultrawideband impulse radio (UWB-IR) transmitter for long-range application. A thorough theoretical analysis of the pulse generation is provided. Implemented in a O.18-µm CMOS, the transmitter works in the UWB lower band of 3-5 GHz and consumes an ultralow average power of 236 µW at 1.8-V power supply. UWB pulses with a bandwidth of 2 GHz and 10-dB sidelobe suppression are generated. The transmitter can deliver a large differential output swing of 4.9 V under 100-Ω load with the highest power efficiency of 25.4% to date. It is targeted for wireless sensor network (WSNs) and wireless personal area network (WPAN) applications.
Minimizing makespan in a two-stage system with flowshop and open shop
Authors: Ling-Huey Su, Fuh-Der Chou, Wei-Ching Ting
Venue: Computers and Industrial Engineering (2005)

This paper studies two models of two-stage processing with flowshop at the first stage followed by open shop at the second stage. The first model involves multiple machines at the first stage and two machines at the second stage, and the other involves multiple machines at both stages. In both models, the objective is to minimize the makespan. This problem is NP-complete, for which an efficient heuristic solution algorithm is constructed and its worst-case performance guarantee is analyzed for both models. An integer programming model and a branch and bound algorithm are proposed for model 1 and a lower bound is developed for model 2 as benchmarks for the heuristic algorithms. Computational experiences show that the heuristic algorithms consistently generate good schedule and the branch and bound algorithm is much efficient than the integer-programming model.