ppxscal/embedding_network huggingface dataset:
Optimal guard time length determination for mobile WiMAX over multipath fading channel
Authors: Waiel Elsayed Osman, Tharek Abd Rahman
Venue: Proceedings of the 8th conference on Applied informatics and communications (2008)

Guard time length (GT) is one of the key OFDM parameters. It is implemented as Cyclic Prefix (CP) to completely alleviate Intersymbol Interference (ISI) and to preserve orthogonality among OFDM subcarriers as long as the guard time length is sufficiently greater than channel delay spread. Conventional OFDM system uses a large GT length to tolerate worst case channel condition irrespective of its current state. This technique, however, degrades the overall spectral efficiency as well as consumes transmitter energy proportional to the length of the guard time. In this paper, we determine the optimal guard time length for mobile WiMAX system over ITU-R M.1225 multipath fading channel. The results show that the optimum values of the GT approximately dependant on the maximum delay spread.
Train-Ground Communication in CBTC Based on 802.11b: Design and Performance Research
Authors: Li Zhu, Yan Zhang, Bin Ning, Hailin Jiang
Venue: Proceedings of the 2009 WRI International Conference on Communications and Mobile Computing - Volume 02 (2009)

The 802.11b physical protocols applied in Communication Based Train Control (CBTC) Train-Ground communication system are simulated in this paper, and the simulation result is used to determine the AP distance. The train speed impact on physical FER is also studied by the simulation result. As a protocol used in a fully mobile outdoor environment, the packet delay and packets loss rate performance of 802.11 DCF is analyzed at last.
An augmented tabletop video game with pinching gesture recognition
Authors: Toshiki Sato, Haruko Mamiya, Hideki Koike, Kentaro Fukuchi
Venue: ACM SIGGRAPH ASIA 2008 artgallery: emerging technologies (2008)

A novel interaction technique for multi-player tabletop entertainment systems. The proposed technique achieves high-response bi-manual interaction by multiple users, and it simultaneously recognises the positions and orientations of the users' hands and pinching gestures.
Searching for Multimedia on the World Wide Web
Authors: Michael J. Swain
Venue: Proceedings of the IEEE International Conference on Multimedia Computing and Systems - Volume 2 (1999)

The proliferation of multimedia on the World Wide Web has led to the introduction of Web search engines for images, video, and audio. On the Web, multimedia is typically embedded within documents that provide a wealth of indexing information. Harsh computational constraints imposed by the economics of advertising-supported searches restrict the complexity of analysis that can be performed at query time. And users may be unwilling to do much more than type a keyword or two to input a query. Therefore, the primary sources of information for indexing multimedia documents are text cues extracted from HTML pages and multimedia document headers. Off-line analysis of the content of multimedia documents can be successfully employed in Web search engines when combined with these other information sources. Content analysis can be used to categorize and summarize multimedia, in addition to providing cues for finding similar documents.
Recognition of Trade Barrier Based on General RBF Neural Network
Authors: Yu Zhao, Miaomiao Yang, Chunjie Qi
Venue: Proceedings of the 2009 International Conference on Computer Engineering and Technology - Volume 01 (2009)

Trade barriers correct externalities, but distort trade as well, which brings negative effect on international distribution of resources. Study on how to recognize there are trade barriers or would-be threat of trade barriers in international trade is of great necessity. Based on previous studies, taking horticultural products as an example, this paper designs a general RBF neural network model to detect whether there are trade barriers among the main destinations of Chinese horticultural products. The study shows that general RBF neural network can identify trade barriers correctly with an error probability about 10%, so it is a helpful tool for identification of trade barriers.
What can we measure?
Authors: Peter Schröder
Venue: ACM SIGGRAPH ASIA 2008 courses (2008)

When characterizing a shape or changes in shape we must first ask, what can we measure about a shape? For example, for a region in R3 we may ask for its volume or its surface area. If the object at hand undergoes deformation due to forces acting on it we may need to formulate the laws governing the change in shape in terms of measurable quantities and their change over time. Usually such measurable quantities for a shape are defined with the help of integral calculus and often require some amount of smoothness on the object to be well defined. In this chapter we will take a more abstract approach to the question of measurable quantities which will allow us to define notions such as mean curvature integrals and the curvature tensor for piecewise linear meshes without having to worry about the meaning of second derivatives in settings in which they do not exist. In fact in this chapter we will give an account of a classical result due to Hadwiger, which shows that for a convex, compact set in Rn there are only n + 1 unique measurements if we require that the measurements be invariant under Euclidian motions (and satisfy certain "sanity" conditions). We will see how these measurements are constructed in a very straightforward and elementary manner and that they can be read off from a characteristic polynomial due to Steiner. This polynomial describes the volume of a family of shapes which arise when we "grow" a given shape. As a practical tool arising from these consideration we will see that there is a well defined notion of the curvature tensor for piece-wise linear meshes and we will see very simple formulas for quantities needed in physical simulation with piecewise linear meshes. Much of the treatment here will initially be limited to convex bodies to keep things simple. This limitation that will be removed at the very end.
Programming wireless sensor networks with the TeenyLime middleware
Authors: Paolo Costa, Luca Mottola, Amy L. Murphy, Gian Pietro Picco
Venue: Proceedings of the ACM/IFIP/USENIX 2007 International Conference on Middleware (2007)

Wireless sensor networks (WSNs) are evolving to support sense-and-react applications, where actuators are physically interspersed with the sensors that trigger them. This solution maximizes localized interactions, improving resource utilization and reducing latency w.r.t. solutions with a centralized sink. Nevertheless, application development becomes more complex: the control logic must be embedded in the network, and coordination among multiple tasks is needed to achieve the application goals. This paper presents TeenyLime, a WSN middleware designed to address the above challenges. TeenyLime provides programmers with the high-level abstraction of a tuple space, enabling data sharing among neighboring devices. These and other WSN-specific constructs simplify the development of a wide range of applications, including sense-and-react ones. TeenyLime yields simpler, cleaner, and more reusable implementations, at the cost of only a very limited decrease in performance. We support these claims through a source-level, quantitative comparison between implementations based on TeenyLime and on mainstream approaches, and by analyzing measures of processing overhead and power consumption obtained through cycle-accurate emulation.
Lie Groups and Lie Algebras
Authors: Nicolas Bourbaki
Venue: Elements Of Mathematics (2008)

From the reviews of the French edition "This is a rich and useful volume. The material it treats has relevance well beyond the theory of Lie groups and algebras, ranging from the geometry of regular polytopes and paving problems to current work on finite simple groups having a (B,N)-pair structure, or "Tits systems". A historical note provides a survey of the contexts in which groups generated by reflections have arisen. A brief introduction includes almost the only other mention of Lie groups and algebras to be found in the volume. Thus the presentation here is really quite independent of Lie theory. The choice of such an approach makes for an elegant, self-contained treatment of some highly interesting mathematics, which can be read with profit and with relative ease by a very wide circle of readers (and with delight by many, if the reviewer is at all representative)." (G.B. Seligman in MathReviews)
An Introduction to Digital Multimedia, 1 edition
Authors: T. M. Savage, K.E. Vogel
Venue:  (2008)

Digital multimedia is a new form of literacy and a powerful tool of creative expression available to nearly everyone. Introduction to Digital Multimedia presents the concepts needed to fully understand multimedia as well as create it. Throughout the text, the authors encourage readers to think critically about the nature of the tools and media they use in order to be more effective, efficient, and creative in their own project development. The text also provides a clear introduction to all the basic concepts and tools of digital multimedia, including the fundamentals of digital data and computer hardware and software, making it appropriate for a first course in computing as well as courses in specific multimedia topics. A multimedia timeline as well as a historical overview of the evolution of multimedia thought and technologies provide background on early visions and possible future innovations. Introduction to Digital Multimedia is the ideal text for those interested in delving into the vast world of multimedia computing.
Microfluidic devices for sample pretreatment and applications
Authors: Xing Chen, Da-Fu Cui
Venue: Microsystem Technologies (2009)

With the fundamentals of microscale flow and species transport well developed, the recent trend in microfluidics has been to work towards the devices capable of dealing with &#x2018;real&#x2019; crude samples directly. Before the real samples reaching the analytical step, it nearly requires significant pre-treated steps. Development of these microdevices that perform sample preprocessing steps is now underway for a broad range of application areas from on-chip DNA analysis, immunoassays to cytometry. This article provides an overview of the latest developments in microfluidic devices for sample pretreatment. Many of the microchips are being designed for individual preprocessing steps, but integration of multiple sample preparation steps has been shown, along with integration of sample preprocessing and analytical procedures on single microchips.
A switchable PLL frequency synthesizer and hot carrier effects
Authors: Yang Liu, Ashok Srivastava, Yao Xu
Venue: Proceedings of the 19th ACM Great Lakes symposium on VLSI (2009)

In this paper, a new strategy of switchable CMOS phase-locked loop frequency synthesizer is proposed, designed and fabricated in 0.5 μm n-well CMOS process. Cadence/Spectre simulation results show that the frequency range of the switchable PLL is between 320 MHz to 1.15 GHz. The experimental results show that the RMS jitter of the PLL changes from 26 ps to 123 ps as output frequency varies. For 700 MHz carrier frequency, the phase noise of PLL reaches as low as -61 dBc/Hz at 10 kHz offset frequency and -104 dBc/Hz at 1 MHz offset frequency. A device degradation model due to hot carrier effects has been used to analyze the jitter and phase noise performance in open loop voltage-controlled oscillator (VCO). The VCO oscillation frequency decreases by approximately 100 to 200 MHz versus the bias voltage and the RMS jitter increases by 40 ps under different PLL output frequencies after 4 hours of stress time.
Cryptographic Hash Functions from Expander Graphs
Authors: Denis X. Charles, Kristin E. Lauter, Eyal Z. Goren
Venue: Journal of Cryptology (2008)

We propose constructing provable collision resistant hash functions from expander graphs in which finding cycles is hard. As examples, we investigate two specific families of optimal expander graphs for provable collision resistant hash function constructions: the families of Ramanujan graphs constructed by Lubotzky-Phillips-Sarnak and Pizer respectively. When the hash function is constructed from one of Pizers Ramanujan graphs, (the set of supersingular elliptic curves over with ℓ-isogenies, ℓ a prime different from p), then collision resistance follows from hardness of computing isogenies between supersingular elliptic curves. For the LPS graphs, the underlying hard problem is a representation problem in group theory. Constructing our hash functions from optimal expander graphs implies that the outputs closely approximate the uniform distribution. This property is useful for arguing that the output is indistinguishable from random sequences of bits. We estimate the cost per bit to compute these hash functions, and we implement our hash function for several members of the Pizer and LPS graph families and give actual timings.
Guidelines for the Analysis of IT Business Models and Strategic Positioning of IT-Products
Authors: Georg Herzwurm, Wolfram Pietsch
Venue: Proceedings of the 2008 Second International Workshop on Software Product Management (2008)

Depending on the perspectives and the stage within the life cycle IT Product are viewed and managed differently. A model is presented that integrates different perspectives and stages serving as an aid for the analysis of business models purposeful and focused positioning of IT-products. Four generic business models are analysed with regard to the product management function in general and the positioning field for IT-products specifically: off-the-shelf, license plus service, project, and system service.
Approximate object location and spam filtering on peer-to-peer systems
Authors: Feng Zhou, Li Zhuang, Ben Y. Zhao, Ling Huang, Anthony D. Joseph, John Kubiatowicz
Venue: Proceedings of the ACM/IFIP/USENIX 2003 International Conference on Middleware (2003)

Recent work in P2P overlay networks allow for decentralized object location and routing (DOLR) across networks based on unique IDs. In this paper, we propose an extension to DOLR systems to publish objects using generic feature vectors instead of content-hashed GUIDs, which enables the systems to locate similar objects. We discuss the design of a distributed text similarity engine, named Approximate Text Addressing (ATA), built on top of this extension that locates objects by their text descriptions. We then outline the design and implementation of a motivating application on ATA, a decentralized spam-"ltering service. We evaluate this system with 30,000 real spam email messages and 10,000 non-spam messages, and "nd a spam identi" cation ratio of over 97% with zero false positives.
Effective inference control mechanisms for securing statistical databases
Authors: Vangalur S. Alagar, Bernard Blanchard, David Glaser
Venue: Proceedings of the May 4-7, 1981, national computer conference (1981)

A database that provides statistical summaries for the purpose of research, planning, and decision making must remain rich, functionally useful, and protected from fraudulent usage. Unless restrictions are placed on the types of queries and responses, protecting an individual's information in the database is impossible. Some effective inference control mechanisms that make it extremely hard for any user to control and compromise a database are discussed. For each method it is argued why the method is effective, supported by some test results.
A Leadership Challenge in 2009
Authors: Susan K. (Kathy) Land
Venue: Computer (2009)

The IEEE Computer Society Board of Governors remains focused on continuing the transformation of the Society so that we can provide increasing value to our membership.
Modeling and development of an ARENA&reg; interface for Petri Nets: a case study in a Colombian cosmetics company
Authors: Gonzalo Mejía, Diego Martínez, Fidel Torres
Venue: Proceedings of the 40th Conference on Winter Simulation (2008)

This paper presents an ARENA&reg;-based library for the development of Timed Colored Petri Net (TCPN) models. In this way, the strengths of Petri Nets and Discrete Event Simulation (DES) are combined in a powerful tool for modeling and analysis of systems. The use of the library is illustrated on a cosmetics manufacturing facility in Bogot&aacute; (Colombia). This facility was modeled via both TCPNs and a classical DES methodology. Extensive analysis shows the advantages and disadvantages of each approach.
Towards a scalable model for location privacy
Authors: Nayot Poolsappasit, Indrakshi Ray
Venue: Proceedings of the SIGSPATIAL ACM GIS 2008 International Workshop on Security and Privacy in GIS and LBS (2008)

With the growth of wireless and mobile technologies, we are witnessing an increase in location-based services (LBS). Although LBS provide enhanced functionalities, they open up new vulnerabilities that can be exploited to cause security and privacy breaches. Specifically, location data of individuals that are used by such services must be protected from security and privacy breaches. Such services will require new models for expressing privacy preferences for location data and mechanisms for enforcing them. We identify the factors on which location privacy depends and propose a scalable model for expressing privacy that can be used for LBS and other applications where the privacy of location information must be protected.
A new-trend model-based to solve the peak power problems in OFDM systems
Authors: Ashraf A. Eltholth, Adel R. Mekhail, A. Elshirbini, M. I. Dessouki, A. I. Abdelfattah
Venue: Modelling and Simulation in Engineering (2008)

The high peak to average power ration (PAR) levels of orthogonal frequency division multiplexing (OFDM) signals attracts the attention of many researchers during the past decade. Existing approaches that attack this PAR issue are abundant, but no systematic framework or comparison between them exist to date. They sometimes even differ in the problem definition itself and consequently in the basic approach to follow. In this paper, we propose a new trend in mitigating the peak power problem in OFDM system based on modeling the effects of clipping and amplifier nonlinearities in an OFDM system. We showed that the distortion due to these effects is highly related to the dynamic range itself rather than the clipping level or the saturation level of the nonlinear amplifier, and thus we propose two criteria to reduce the dynamic range of the OFDM, namely, the use of MSK modulation and the use of Hadamard transform. Computer simulations of the OFDM system using Matlab are completely matched with the deduced model in terms of OFDM signal quality metrics such as BER, ACPR, and EVM. Also simulation results show that even the reduction of PAR using the two proposed criteria is not significat, the reduction in the amount of distortion due to HPA is truley delightful.
Implementation of a Fast Reassembly Methodology for Polygon Fragment
Authors: Gang Xu, Yi Xian
Venue: Proceedings of the 2009 International Asia Conference on Informatics in Control, Automation and Robotics (2009)

The polygon image fragment is a special fragment type, whose sides is composed of straight line segment, and it has seldom been researched. In this paper, a new image fragment reassembly methodology based on corner detection and gray correlation is proposed for polygon fragments. The experimentation indicates the reassembly methodology based on corner detection and gray correlation can get good result, although there are rotation, translation and noise between image fragments.
Proceedings of the 3rd ACM Workshop on System-level Virtualization for High Performance Computing
Venue: European Conference on Computer Systems (2009)

The emergence of virtualization enabled hardware, such as the latest generation AMD and Intel processors, has raised significant interest in High Performance Computing (HPC) community. In particular, system-level virtualization provides an opportunity to advance the design and development of operating systems, programming environments, administration practices, and resource management tools. This leads to some potential research topics for HPC, such as failure tolerance, system management, and solution for application porting to new HPC platforms. The workshop on System-level Virtualization for HPC (HPCVirt 2009) is intended to be a forum for the exchange of ideas and experiences on the use of virtualization technologies for HPC, the challenges and opportunities offered by the development of system-level virtualization solutions themselves, as well as case studies in the application of system-level virtualization in HPC.
Properties of Generalized Polynomial Spaces in Three Variables
Authors: Dana Simian
Venue: Numerical Analysis and Its Applications: 4th International Conference, NAA 2008, Lozenetz, Bulgaria, June 16-20, 2008. Revised Selected Papers (2009)

Multivariate interpolation is a topic which often appears in practical modeling problems. Different type of spaces of functions are used for solving interpolation problems. When the interpolation conditions are of different kind, by example, spacial and temporal, one possibility for modeling the problem is to use a generalize degree, in which the monomials exponents are weighted with a weight vector with integer components. In order to use such a generalize polynomial space as interpolation space, it is necessary to know the dimension and a basis of it. The aim of this article is to study and prove many properties of the generalize polynomial spaces in three variables.
Resource optimization in distributed biometric recognition using wireless sensor network
Authors: Rajani Muraleedharan, Lisa Ann Osadciw, Yanjun Yan
Venue: Multidimensional Systems and Signal Processing (2009)

Distributed, autonomous and energy efficient protocols are best suited for wireless sensor networks, where network needs and events are dynamic. In this paper, a wireless face recognition system with limited resources such as energy, memory and bandwidth is analyzed. The performance of the applications is influenced by the protocol adaptability and quality of information. Performance comparisons are completed using 1. In-network image compression using Contourlet and Wavelet transforms versus raw image data transmission, 2. longevity of sensors versus network throughput. Balancing resource constraints, maintaining network lifetime and throughput is a non-deterministic polynomial computation time problem. Thus a meta-heuristic combinatorial algorithm, based on swarm intelligence, forms the cognitive routing protocol. The network efficiency considers energy consumption, response time, probability of correct acceptance, processing and computation time for wireless image transmission.
Super-high speed fiber optical communication system design and simulation
Authors: Kaikai Xu, David Cheng, Kaicheng Li
Venue: Proceedings of the 2008 International Conference on Advanced Infocomm Technology (2008)

WDM is the most classic techniques in optical networks. WDM technology allows the capacity of a fiber by the multi-wavelengths transmission increases to several dozens times, and even several hundred times by comparing with the single-wavelength transmission capacity. In view of the broad prospects of WDM communication systems, this essay has done an in-depth study and research on WDM. Then, design an 80 Gbps dense-WDM communication system and analyze the performance of this communication system by BER standard. And the simulation results show that: the design is feasible.