ppxscal/embedding_network huggingface dataset:
Note: Points with large α-depth
Authors: Itay Ben-Dan, Rom Pinchasi, Ran Ziv
Venue: Journal of Combinatorial Theory Series A (2009)

We show that for every @e>0 there exists an angle @a=@a(@e) between 0 and @p, depending only on @e, with the following two properties: (1) For any continuous probability measure in the plane one can find two lines @?"1 and @?"2, crossing at an angle of (at least) @a, such that the measure of each of the two opposite quadrants of angle @p-@a, determined by @?"1 and @?"2, is at least 12-@e. (2) For any set P of n points in general position in the plane one can find two lines @?"1 and @?"2, crossing at an angle of (at least) @a and moreover at a point of P, such that in each of the two opposite quadrants of angle @p-@a, determined by @?"1 and @?"2, there are at least (12-@e)n-4 points of P.
FPCNA: a field programmable carbon nanotube array
Authors: Chen Dong, Scott Chilstedt, Deming Chen
Venue: Proceeding of the ACM/SIGDA international symposium on Field programmable gate arrays (2009)

Carbon nanotubes (CNTs), with their unique electronic properties, are promising materials for building nanoscale circuits. In this paper, we present a new CNT-based FPGA architecture known as FPCNA. We define novel CNT and nanoswitch based components and characterize these components considering nano-specific process variations, including the variation caused by the random mixture of metallic and semiconducting CNTs. To evaluate the architecture, we develop a variation-aware physical-design flow which can handle both Gaussian and non-Gaussian random variables using variation-aware placement and routing. When FPCNA is evaluated with this CAD flow, we see a 2.67× performance gain over a baseline CMOS FPGA at the same technology node (at a 95% performance yield). In addition, FPCNA offers a 4.5× footprint reduction compared to the baseline FPGA. These results demonstrate the potential of using CNTs and nanoswitches to build high performance FPGA circuits.
An Empirical Approach of Delta Hedging in GARCH Model
Authors: Qian Chen, Chengzhe Bai
Venue: Proceedings of the 2009 International Conference on Computer Engineering and Technology - Volume 01 (2009)

In this paper, we compare the costs and efficiency arising from the delta-neutral dynamic hedging of options, using two possible values for the delta of the option. The first one is the traditional Black-Scholes delta, while the second one is the GARCH option pricing delta, namely the delta of the option in the generalized Black-Scholes model with a volatility calibrated from GARCH model. Both our theoretical analysis and empirical results of S&P 500 index options showed that single-factor version of the GARCH delta showed better performance than B-S delta (1973), especially when the volatility are very high. We believe the improvement is due largely to the ability of the GARCH model to describe the correlation of volatility with spot returns. This allows the GARCH model to capture strike-price biases in the Black-Scholes model that give rise to the skew in implied volatilities in the index options market.
Proceedings of the 2009 symposium on Interactive 3D graphics and games
Venue: Symposium on Interactive 3D Graphics (2009)

These are the proceedings of the 2009 ACM SIGGRAPH Symposium on Interactive 3D Graphics and Games. I3D has been held thirteen times since the first symposium in 1986 and is now an annual event with a strong community. This year we return to the East coast and meet in Boston, Massachusetts, from February 27th to March 1st, 2009. I3D brings together researchers and practitioners in the field of interactive graphics, fostering an exchange of ideas and information. By focusing on a particular area of study, the symposium allows attendees to easily meet with their peers, something that can be more problematic at large conferences. During the symposium the technical papers enclosed are presented, along with a poster session and invited talks. The heart of the conference is the content of the proceedings. We thank and congratulate the authors whose papers are included, knowing that their ideas provide insights and value to the community. We encourage anyone who appreciates this content to consider submitting their research work to future symposia. These proceedings contain 28 papers that were accepted out of 87 submissions. A program committee of 82 members, along with 14 external reviewers, carefully reviewed the submissions, with all submissions receiving at least three reviews. All in all, well over 300 reviews were written. Each paper submitted was judged on its own merits; no quotas or goals were imposed on the number accepted.
Overlap-freeness in infinite partial words
Authors: Vesa Halava, Tero Harju, Tomi Kärki, Patrice Séébold
Venue: Theoretical Computer Science (2009)

We prove that there exist infinitely many infinite overlap-free binary partial words containing at least one hole. Moreover, we show that these words cannot contain more than one hole and the only hole must occur either in the first or in the second position. We define that a partial word is k-overlap-free if it does not contain a factor of the form xyxyx where the length of x is at least k. We prove that there exist infinitely many 2-overlap-free binary partial words containing an infinite number of holes.
Benders decomposition applied to multi-commodity, multi-mode distribution planning
Authors: Ozan Çakır
Venue: Expert Systems with Applications: An International Journal (2009)

We discuss the solution of a multi-commodity, multi-mode distribution planning problem arising in tactical level supply chain decisions, with using a primal decomposition algorithm, namely, the Benders decomposition. We provide a detailed Benders reformulation of the problem and illustrate the procedure on an example scenario. Benders algorithm, when experimented on this scenario converged to the original MIP solution showing the Benders reformulation of the problem is valid.
Scalable server system based on virtual machine duplication in wide area
Authors: Yuko Kamiya, Toshihiko Shimokawa, Norihiko Yoshida
Venue: Proceedings of the 3rd International Conference on Ubiquitous Information Management and Communication (2009)

In the Internet world, server systems play a crucial role in continuously supporting the 24/7 operation of the network. However, some problem issues have been identified with the current server systems on the Internet. In this research, we tackle two of these problems, i.e., the processing power and network bandwidths, and proposed solutions on these issues. In this research, we use virtual machines to solve the above-mentioned problems. Generally, a virtual machine consists of some files which are easy to increase. By duplicating a virtual machine, we can increase processing power of the servers. Likewise, by tapping the wide bandwidth of a high-performance processing server, we can increase the network bandwidth. We call this idea, Server Proliferation. We designed the Virtual Machine Control Protocol (VMCP) to implement Server Proliferation. VMCP has six basic functions; namely, to authenticate users, to get information, to apply information to a virtual machine, to transfer virtual machine, to control virtual machine, and to provide help functions. We implemented a prototype system of VMCP, called PIYO (ProlIferate and Yield Objects). PIYO is a server-client system. Lastly, we evaluated Server Proliferation by using PIYO.
The structure of modular walking robot MERO displacement systems, support of the heavy load transportation
Authors: Ion Ion, Luige Vladareanu, Ion Simionescu, Aurelian Vasile
Venue: WSEAS Transactions on Systems and Control (2009)

The modular constructions of the walking robots led to a more suppleness and very good adaptation to any terrain surface. Some of the most significant components of the walking robots are the mechanisms of the displacement systems. The design of the leg mechanisms implies the solving of several problems regarding the static stability, the forces distribution, balancing of the gravitational forces in order to diminish the power consumption, optimization of the foot sole shape, optimization of the kinematic dimensions of the leg etc The advantages of legged system for off-road have been gradually recognised. One of the most important advantages is mobility. The Modular walking robots represent a special category of robots, characterized by having the power source embarked on the platform. The weight of this source is an important part of the total charge that the walking robot must transport. That is the reason why the walking system must be designed so that the mechanical work necessary for displacement, or the highest power necessary for act it, should be minimal A modular walking robot can traverses most natural terrain. Walking robots better protect the environment, as their contact to the ground is discrete, which considerably diminishes the area underwent to crushing; the robot's weight can be optimally distributed all over the supporting surface, by controlling the forces. Altering the distance to the ground, the robot can pass over young trees or other vegetation, growing in the passage area.
Visualizing Occluded Physical Objects in Unfamiliar Outdoor Augmented Reality Environments
Authors: Benjamin Avery, Wayne Piekarski, Bruce H. Thomas
Venue: Proceedings of the 2007 6th IEEE and ACM International Symposium on Mixed and Augmented Reality (2007)

This paper describes techniques to allow both the visualization of hidden objects, and removal of real objects, for a mobile augmented reality user. A gesture based technique is also described which allows the user to select when to view occluded objects. By using the real-time modeling techniques of the Tinmith system, the user is able to create the required geometry to allow image based rendering techniques to be used to render corrected images on the user's display. The images of the hidden objects are captured by a mobile robot platform that is controlled by the mobile user.
On the Linear Span of a Binary Sequence Family with Optimal Correlation Properties
Authors: Xiangyong Zeng, John Q. Liu, Lei Hu, Desmond P. Taylor
Venue: IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences (2008)

A new subfamily of sequences with optimal correlation properties is constructed for the generalized Kasami set. A lower bound on the linear span is established. It is proved that with suitable choices of parameters, this subfamily has exponentially larger linear spans than either No sequences or TN sequences. A class of sequences with ideal autocorrelation is also proved to have large linear span.
Inferring player engagement in a pervasive experience
Authors: Joel E. Fischer, Steve Benford
Venue: Proceedings of the 27th international conference on Human factors in computing systems (2009)

We investigate the prediction of player engagement to address temporal issues arising from the long-term character of pervasive experiences such as interruptibility, mutual player state awareness, disengagement and synchronization on re-engagement. We introduce a model that operationalizes engagement in terms of the elapsed and response time in game messages. We designed and conducted an experiment based on the experience-sampling method to evaluate our model on the basis of a long-term SMS-based game called Day of the Figurines. Statistical analysis supports the hypothesis that player engagement can be predicted by the continuous data properties elapsed time and response time. Our findings point towards further research towards the adaptation of pervasive experiences to the player's temporal context.
Neural network based handwritten hindi character recognition system
Authors: Dayashankar Singh, Maitreyee Dutta, Sarvpal H. Singh
Venue: Proceedings of the 2nd Bangalore Annual Compute Conference (2009)

Neural Networks are being used for character recognition from last many years but most of the works were reported to English character recognition. Character recognition is one of the applications of pattern recognition, which has enormous scientific and practical interest. Many scientific efforts have been dedicated to pattern recognition problems and much attention has been paid to develop recognition system that must be able to recognize a character. The main driving force behind neural network research is the desire to create a machine that works similar to the manner our own brain works. Neural networks have been used in a variety of different areas to solve a wide range of problems. A very little work has been reported for Handwritten Hindi Character recognition. In this paper, we have implemented Gradient feature extraction technique, which provides more than 94% recognition accuracy. We have acquired 1000 samples of handwritten Hindi characters by initializing the mouse in graphics mode. The 500 samples have been used for training the network (Train Data) and remaining 500 samples have been used for testing the network (Test Data). The system has been trained using several different forms of handwritings provided by both male and female participants of different age groups. Finally, this rigorous training results an automatic HCR system using MLP network. The error backpropagation algorithm has been used to train the MLP network. A comparative analysis was performed by implementing both global input and Gradient feature input. We have concluded that gradient feature extraction technique provides better recognition accuracy with reduced training time.
Memory Locality Exploitation Strategies for FFT on the CUDA Architecture
Authors: Eladio Gutierrez, Sergio Romero, Maria A. Trenas, Emilio L. Zapata
Venue: High Performance Computing for Computational Science - VECPAR 2008: 8th International Conference, Toulouse, France, June 24-27, 2008. Revised Selected Papers (2008)

Modern graphics processing units (GPU) are becoming more and more suitable for general purpose computing due to its growing computational power. These commodity processors follow, in general, a parallel SIMD execution model whose efficiency is subject to a right exploitation of the explicit memory hierarchy, among other factors. In this paper we analyze the implementation of the Fast Fourier Transform using the programming model of the Compute Unified Device Architecture (CUDA) recently released by NVIDIA for its new graphics platforms. Within this model we propose an FFT implementation that takes into account memory reference locality issues that are crucial in order to achieve a high execution performance. This proposal has been experimentally tested and compared with other well known approaches such as the manufacturer's FFT library.
Composing Stack-Attributed Tree Transducers
Authors: Keisuke Nakano
Venue: Theory of Computing Systems (2008)

Stack-attributed tree transducers extend attributed tree transducers with a pushdown stack device for attribute values, which make them strictly more powerful. This paper presents an algorithm for the composition of stack-attributed tree transducers with attributed tree transducers. The algorithm is an extension of the existing method to compose attributed tree transducers. It leads to some natural closure properties of the corresponding classes of tree transformations.
A novel approach for fast covering the Boolean sets
Authors: Fatih Basççiftçi, Sirzat Kahramanli
Venue: Proceedings of the 8th conference on Systems theory and scientific computation (2008)

In this study we propose a new method for iteratively covering given Boolean data set by its prime implicants identified one at a time. In contrast to existing set covering methods of NP time complexity in the size of the set, our method is realized by procedures of linear complexity and therefore its efficiency is rapidly increased by increasing the size of the set. Our method can be useful in all fields related to Boolean data sets processing such as logic synthesis, image processing, data compressing, artificial intelligence and many others.
Failure recovery for multi-party real-time communication
Venue: Proceedings of the 1996 International Conference on Multimedia Computing and Systems (1996)

For real-time communication services to achieve widespread usage, it is important that the network services behave gracefully when any component fails. In this paper, we describe techniques and mechanisms for maintaining network services for multi-party real-time communication in the face of failures that may make parts of the network inaccessible. These protocols provide high performance during normal operations and the network performance degrades gracefully in face of network failures; e.g., in the presence of failures, the routes selected may not be optimal, the connection set-up may take a little more time, or resource allocation may be less efficient. We describe appropriate policies for storing state in the network, as well as the mechanisms for re-establishing connectivity for previously established connections and to permit setting up new connections to existing conferences. We also describe a redundancy-based approach, using forward error correction (FEC), and dispersing the FEC'ed data among disjoint routes. With these mechanisms, the real-time communication protocols achieve robustness to single and/or multiple failures in the network, without diluting the strength of the performance guarantees offered, or sacrificing the system performance in the common case. 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
Virtual organizational learning in open source software development projects
Authors: Yoris A. Au, Darrell Carpenter, Xiaogang Chen, Jan G. Clark
Venue: Information and Management (2009)

We studied virtual organizational learning in open source software (OSS) development projects. Specifically, our research focused on learning effects of OSS projects and the factors that affect the learning process. The number and percentage of resolved bugs and bug resolution time of 118 SourceForge.net OSS projects were used to measure the learning effects. Projects were characterized by project type, number and experience of developers, number of bugs, and bug resolution time. Our results provided evidence of virtual organizational learning in OSS development projects and support for several factors as determinants of performance. Team size was a significant predictor, with mid-sized project teams functioning best. Teams of three to seven developers exhibited the highest efficiency over time and teams of eight to 15 produced the lowest mean time for bug resolution. Increasing the percentage of bugs assigned to specific developers or boosting developer participation in other OSS projects also improved performance. Furthermore, project type introduced variability in project team performance.
Intelligent wheelchair (IW) interface using face and mouth recognition
Authors: Jin Sun Ju, Yunhee Shin, Eun Yi Kim
Venue: Proceedings of the 13th international conference on Intelligent user interfaces (2009)

between the user and the wheelchair. To facilitate a wide variety of user abilities, the proposed system uses faceinclination and mouth-shape information as user's intention, where the direction of an IW is determined by the inclination of the user's face, while proceeding and stopping are determined by the shape of the user's mouth. This mechanism requires minimal motion, thereby making the system more comfortable and adaptable for the severely disabled. Furthermore, to fully guarantee user's safety, the 10 range-sensors are used to detect obstacles in environment and avoid them. To assess the effectiveness of the proposed IW, it was tested with 34 users and the results show that it can provide a user unable to drive a standard joystick with friendly and convenient system
Design of an Autonomous Surface Vehicle Used for Marine Environment Monitoring
Authors: Jianhua Wang, Wei Gu, Jianxin Zhu
Venue: Proceedings of the 2009 International Conference on Advanced Computer Control (2009)

This paper presents the design of an Autonomous Surface Vehicle (ASV) used for marine environment monitoring or hydrologic survey. A catamaran is used to improve stability against waves, and the shape of high-speed ship is exploited to reduce the resistance. The characteristics of resistance, electric motor and propeller are optimally matched, so that the battery power is saved and the endurance is improved. By using wireless local loop based on IP, the reliability of remotely operated system is increased and distance of effective communication is extended. All the compartmentalized cabins are modularized and configured with universal data interfaces to facilitate connecting various instruments. Tests on near sea show that the ASV can do both fixed-spot observation as a moored buoy and cruise observation as a survey vessel. In addition, it can reach shallow areas where a survey vessel cannot access. Therefore, it can be widely used on water surface of river, lake and ocean for environment monitoring, survey and exploration.
Feed forward backpropagation algorithm for estimating reference evapotranspiration in Burkina Faso
Authors: Yu-Min Wang, Seydou Traore, Tienfuan Kerh
Venue: Proceedings of the 12th WSEAS international conference on Computers (2008)

Reference evapotranspiration (ETo) identified as a key hydrological variable, has been widely used for agricultural water management. Its accurate estimation is vitally important for computerizing crop water balance analysis. The sole recommended method for ETo computation is the Penman-Monteith (PM) equation which requires data that are not always available particularly for a developing country such as Burkina Faso. Therefore, a previous study has developed a reference model for Burkina Faso (RMBF) for estimating the ETo by using only temperature as input in two production sites, Banfora and Ouagadougou. This paper investigates for the first time in the semiarid environment of Burkina Faso, the potential of using an artificial neural network (ANN) with limited climatic data set. The ANN model employed in the study was the feed forward backpropagation (BP) type using maximum and minimum air temperature collected from 1996 to 2006. The BP was compared to the RMBF, Hargreaves (HRG) and Blaney-Criddle (BCR) which have been successfully used for ETo estimation where there is not sufficient data. Based on the results of this study, it revealed that the BP prediction showed a higher accuracy than RMBF, HRG and BCR. The feed forward backpropagation algorithm could be potentially employed successfully to estimate ETo in semiarid zone.
Design and fabrication of highly nonlinear photonic crystal fiber
Authors: Liu Hairong, Liu Deming, Huang Yuanyuan, Tong Weijun
Venue: Proceedings of the 2008 International Conference on Advanced Infocomm Technology (2008)

In this paper a highly nonlinear photonic crystal fiber is designed and fabricated. The design process and the simulation results of the dispersion and nonlinear coefficient with changing of the structure of the photonic crystal fiber have also been presented. Refer to the design structure of the photonics crystal fiber the fabricated fiber is characteristic with a flatten dispersion curve at 800nm wave band and the dispersion at wavelength of 800nm is about -40ps/nm/km. Supercontinuum emission with spectrum stretching over 900nm is obtained by injecting 30fs Ti: sapphire laser pulses with a pulse repetition rate of 80 MHz and a central wavelength of 805 nm into 50 meters of such a photonic crystal fiber