ppxscal/embedding_network huggingface dataset:
Serious fun in computer science
Authors: Paul Curzon
Venue: ACM SIGCSE Bulletin (2007)

Computer Science has been in crisis for several years. Interest in studying it has dropped dramatically. We can wring our hands, or we can do something about it. Computer Science needs to engage with pure outreach: selling the subject (for free). Our approach has been to do this by just going out and having innovative fun. This is more effective than selling specific courses or institutions. CS is after all a naturally exciting, innovative and thought-provoking subject (Oh, and by the way there are good jobs at the end too). We see it as a Renaissance subject (so who cares what it's called or which variation the future depends on). It sits in a unique position, centrally connected to all of the sciences, arts and humanities. We are passionate about science generally, so we go out and spread that enthusiasm about it all. What have we been doing? There is cs4fn (www.cs4fn.org) a website and magazine that we've been writing for the sheer enjoyment of it; Sodarace (www.sodarace.net) where over 130 000 registered humans and computers compete in an online Olympics; Brain Academy (www.brainacademy.qmul.ac.uk), the Compute-Ability competition with career enhancing prizes; research talks for kids on Artificial Intelligence, women in technology, disability and mutant super-hero powers (actually its about search algorithms) and so on; a Computer Science Magic show (you have to promise not to tell anyone the secrets); and exhibits at the Royal Society Summer Exhibition on mathematical illusions and their link to computer science (www.cs4fn.org/illusions). We build brains that play Snap from rope and toilet roll, and introduce a piece of paper more intelligent than anyone in the room. Kids act out Turing Tests (can you tell the human from the robot?), and we challenge them to solve puzzles with CS twists. We do real research too of course: a spin-out of our EPSRC funded research project on Human Error and Interactive Systems includes an online SpaceInvaders game-experiment (www.cs4fn.org/humanerror) the data from which helps us understand the causes of human error: can you consistently avoid making the mistake that will blow up your ship and lose all your points?. What age group should we be targeting? Sixth formers? A major issue is that school ICT, vital as it is, gives a poor impression of how being a computer scientist is about being an innovative, creative, computational thinker. By the sixth form it is too late. It is the younger kids we have to get the message to. An early experiment has been teaching a version of a graduate level course on usability evaluation to primary school kids (www.cs4fn.org/manorside). They proved to be very innovative and "amazing", "will stay in my mind forever", "I want to teach others in the school what we did" were some of their comments. Our approach works: teachers, industry and the International Review of ICT have commended us & and we have seen an increase in undergraduate applications of over 130% in 2 years. Not bad when we are just having fun: serious fun.
Optimizing Data Decomposition for Data Parallel Programs
Authors: Hong Xu, Lionel M. Ni
Venue: Proceedings of the 1994 International Conference on Parallel Processing - Volume 02 (1994)

A critical issue in achieving the performance of data parallel programs is how to efficiently decompose data across processors. On distributed-memory machines, a good data decomposition should increase processor workload balance and reduce interprocessor communication. Data decomposition consists of data distribution and data alignment. In this paper, we propose a trapezoid data distribution pattern and new data alignment algorithms using alignment graph (AG). Our AG-based alignment framework is unique from other related work because it takes advantage of the effect of optimal expression evaluation with regard to multiple assignment statements.
A packet pre-classification CSMA/CA MAC protocol for IP over WDM ring networks
Authors: Wen-Ping Chen, Wen-Shyang Hwang
Venue: Proceedings of the The 8th International Conference on Communication Systems - Volume 02 (2002)

A packet pre-classification MAC (media access control) protocol based on carrier sense multiple access with collision avoidance (CSMA/CA) scheme has been investigated for supporting IP packet over the all-optical WDM ring networks. The intention of the protocol is to increase throughput of IP over optical networks in metropolitan area network (MAN). This protocol avoids both packet collision and packet fragmentation. In order to improve the utilization of network, the packets transmitted from local area network (LAN) are pre-classified into various class queues of access point (AP) according their length. Simulations had been done to evaluate the performance of the protocol, and the simulation results show extraordinarily good network efficiency.
An Integrated Service Selection Engine for Context-aware Computing
Authors: Hong Ling, Tao Dong, Zhengchuan Xu, Peiqiang Tan
Venue: Proceedings of the International Conference on the Management of Mobile Business (2007)

Context-aware computing is expected to be a key enabler for customized provision of fast-growing mobile services. The growth on the number and diversity of mobile services makes current approach and practice of service selection inadequate.
Decision-tree instance-space decomposition with grouped gain-ratio
Authors: Shahar Cohen, Lior Rokach, Oded Maimon
Venue: Information Sciences: an International Journal (2007)

This paper examines a decision-tree framework for instance-space decomposition. According to the framework, the original instance-space is hierarchically partitioned into multiple subspaces and a distinct classifier is assigned to each subspace. Subsequently, an unlabeled, previously-unseen instance is classified by employing the classifier that was assigned to the subspace to which the instance belongs. After describing the framework, the paper suggests a novel splitting-rule for the framework and presents an experimental study, which was conducted, to compare various implementations of the framework. The study indicates that using the novel splitting-rule, previously presented implementations of the framework, can be improved in terms of accuracy and computation time.
Grid Multi-Resolution Docking
Authors: J. I. Garzon, E. Huedo, R. S. Montero, I. M. Llorente, P. Chacon
Venue: Proceedings of the 15th Euromicro International Conference on Parallel, Distributed and Network-Based Processing (2007)

Detailed knowledge of macromolecular structure is essential for the understanding of how the cellular machines work. Rigid body fitting is the common way to interpret the information contained in a 3D electron microscope (3DEM) medium-low resolution map in terms of its available atomic structural components. This fitting process, termed multiresolution docking, consists in localizing atomic resolution structures into the 3DEM map by means of an exhaustive search of all possible relative rotations and translations. This exhaustive search is a highly computing demanding process and several search queries are also typically needed to select good fitting structures. Here, we present a novel and efficient Grid approach for performing these docking searches. This approach has been designed over the Gridway meta-scheduler. Results showing the high efficiency achieved are discussed together with the corresponding analysis of the performance obtained. The experiments were conducted on a Grid testbed built up from resources inside EGEE (LCG version of the pre-WS Globus components), the European production-level Grid infrastructure, and resources from a research testbed based on the Globus Toolkit 4 (Web Services components).
An architecture for content routing support in the internet
Authors: Mark Gritter, David R. Cheriton
Venue: Proceedings of the 3rd conference on USENIX Symposium on Internet Technologies and Systems - Volume 3 (2001)

The primary use of the Internet is content distribution -- the delivery of web pages, audio, and video to client applications -- yet the Internet was never architected for scalable content delivery. The result has been a proliferation of proprietary protocols and ad hoc mechanisms to meet growing content demand. In this paper, we describe a content routing design based on name-based routing as part of an explicit Internet content layer. We claim that this content routing is a natural extension of current Internet directory and routing systems, allows efficient content location, and can be implemented to scale with the Internet.
Analysis of the Parareal Time-Parallel Time-Integration Method
Authors: Martin J. Gander, Stefan Vandewalle
Venue: SIAM Journal on Scientific Computing (2007)

The parareal algorithm is a method to solve time-dependent problems parallel in time: it approximates parts of the solution later in time simultaneously to parts of the solution earlier in time. In this paper the relation of the parareal algorithm to space-time multigrid and multiple shooting methods is first briefly discussed. The focus of the paper is on new convergence results that show superlinear convergence of the algorithm when used on bounded time intervals, and linear convergence for unbounded intervals.
Detecting Coordinated Distributed Multiple Attacks
Authors: S. Mukkamala, K. Yendrapalli, R. B. Basnet, A. H. Sung
Venue: Proceedings of the 21st International Conference on Advanced Information Networking and Applications Workshops - Volume 01 (2007)

This paper describes results concerning the robustness and generalization capabilities of kernel methods in detecting coordinated distributed multiple attacks (CDMA) using network audit trails. We also evaluate the performance of denial of service detection models built using the key features in detecting a new attack scheme; CDMA. The data is generated by carrying out the attack (CDMA) in a closed environment at New Mexico Tech Information Assurance Laboratory. We use traditional support vector machines (SVM), biased support vector machine (BSVM) and leave-one-out model selection for support vector machines (looms) for model selection. We also evaluate the impact of kernel type and parameter values on the accuracy of a support vector machine (SVM) performing CDMA classification. We show that classification accuracy varies with the kernel type and the parameter values; thus, with appropriately chosen parameter values, CDMA can be detected by SVMs and BSVMs with higher accuracy and lower rates of false alarms.
Multi-source localization in reverberant environments by ROOT-MUSIC and clustering
Authors: E. D. Di Claudio
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 02 (2000)

Localization of acoustic sources in reverberant environments by microphone arrays remains a challenging task in audio signal processing. As a matter of fact, most assumptions of commonly adopted models are not met in real applications. Moreover, in practical systems it is not convenient or possible to employ sophisticated and costly architectures, that require precise synchronization and fast data shuffling among sensors. In this paper, a new robust multi-step procedure for speaker localization in reverberant rooms is introduced and described. The new approach is based on a disturbed harmonics model of time delays in the frequency domain and employs the well-known ROOT-MUSIC algorithm, after a preliminary distributed processing of the received signals. Candidate source positions are then estimated by clustering of raw TDOA estimates. Main features of the proposed approach, compared to previous solutions, are the capability of tracking multiple speakers and the high accuracy of the closed form TDOA estimator.
An Interior-Point Trust-Region Algorithm for General Symmetric Cone Programming
Authors: Ye Lu, Ya-Xiang Yuan
Venue: SIAM Journal on Optimization (2007)

An interior-point trust-region algorithm is proposed for minimizing a general (non-convex) quadratic objective function in the intersection of a symmetric cone and an affine subspace. The algorithm uses a trust-region model to ensure descent on a suitable merit function. Global first-order and second-order convergence results are proved. Numerical results are presented.
HP2P: A Hybrid Hierarchical P2P Network
Authors: Zhuo Peng, Zhenhua Duan, Jian-Jun Qi, Yang Cao, Ertao Lv
Venue: Proceedings of the First International Conference on the Digital Society (2007)

Unstructured and structured P2P are two typical distributed models for P2P networking. The unstructured P2P uses flooding method, and has poor scalability and low efficiency, while the structured P2P uses DHT (Distributed Hash Table) method, and has low stability. This paper proposes a two-layer hybrid P2P network - HP2P, which combines flooding and DHT methods: Chord is used for the upper layer and flooding for the lower layer. The general framework of HP2P is presented and its upper and lower layers are described. By analyzing the performance of HP2P, it shows that HP2P has well scalability, high efficiency, and good stability.
Implementing a generalized drag-and-drop in X
Authors: Cui-Qing Yang, Shrinand Desai
Venue: Proceedings of the USENIX Applications Development Symposium Proceedings on USENIX Applications Development Symposium Proceedings (1994)

Drag-and-drop operation is a well-recognized and widely applied mechanism in the development of graphical user interfaces (GUIs). Most of current approaches in design and implementation of such a operation are limited to some specific objects (such as icons or drag-and-drop widgets), and are usually complex, system-dependent, and time-consuming. This paper proposes a generalized semantic and protocol for drag-and-drop that makes the draggable and droppable as intrinsic properties of any GUI objects (just like the colors and other appearance of an object) and allows each object to customize its own semantic of drag-and-drop. Therefore, the drag-and-drop feature is integrated as an inherent part of a GUI window system and all details and complexities of its implementation can be hidden from end users. The framework of generalized drag-and-drop could be applied to any GUI system. A prototype implementation in the Xt Athena widget set of X11R5 on a Unix system is reported in the paper.
Using storytelling to motivate programming
Authors: Caitlin Kelleher, Randy Pausch
Venue: Communications of the ACM (2007)

Using the Storytelling Alice programming environment to create computer-animated movies inspires middle school girls' interest in learning to program computers.
Multiple Description Coding for Stationary and Ergodic Sources
Authors: Jun Chen, Chao Tian, Suhas Diggavi
Venue: Proceedings of the 2007 Data Compression Conference (2007)

We consider the problem of multiple description (MD) coding for stationary sources with the squared error distortion measure. The MD rate region is derived for the stationary and ergodic Gaussian sources, and is shown to be achievable with a practical transform lattice quantization scheme. Moreover, the proposed scheme is asymptotically optimal at high resolution for all stationary sources with finite differential entropy rate.
EWD: A metamodeling driven customizable multi-MoC system modeling framework
Authors: Deepak Mathaikutty, Hiren Patel, Sandeep Shukla, Axel Jantsch
Venue: ACM Transactions on Design Automation of Electronic Systems (TODAES) (2007)

We present the EWD design environment and methodology, a modeling and simulation framework suited for complex and heterogeneous embedded systems with varying degrees of expressibility and modeling fidelity. This environment promotes the use of multiple models of computation (MoCs) to support heterogeneity and metamodeling for conformance tests of syntactic and static semantics during the process of modeling. Therefore, EWD is a multiple MoC modeling and simulation framework that ensures conformance of the MoC formalisms during model construction using a metamodeling approach. In addition, EWD provides a suite of translation tools that generate executable models for two simulation frameworks to demonstrate its language-independent modeling framework. The EWD methodology uses the Generic Modeling Environment for customization of the MoC-specific modeling syntax into a visual representation. To embed the execution semantics of the MoCs into the models, we have built parsing and translation tools that leverage an XML-based interoperability language. This interoperability language is then translated into executable Standard ML or Haskell models that can also be analyzed by existing simulation frameworks such as SML-Sys or ForSyDe. In summary, EWD is a metamodeling driven multitarget design environment with multi-MoC modeling capability.
Goldilocks: a race and transaction-aware java runtime
Authors: Tayfun Elmas, Shaz Qadeer, Serdar Tasiran
Venue: ACM SIGPLAN Notices (2007)

Data races often result in unexpected and erroneous behavior. In addition to causing data corruption and leading programs to crash, the presence of data races complicates the semantics of an execution which might no longer be sequentially consistent. Motivated by these observations, we have designed and implemented a Java runtime system that monitors program executions and throws a DataRaceException when a data race is about to occur. Analogous to other runtime exceptions, the DataRaceException provides two key benefits. First, accesses causing race conditions are interruptedand handled before they cause errors that may be difficult to diagnose later. Second, if no DataRaceException is thrown in an execution, it is guaranteed to be sequentially consistent. This strong guarantee helps to rule out many concurrency-related possibilities as the cause of erroneous behavior. When a DataRaceException is caught, the operation, thread, or program causing it can be terminated gracefully. Alternatively, the DataRaceException can serve as a conflict-detection mechanism inoptimistic uses of concurrency. We start with the definition of data-race-free executions in the Java memory model. We generalize this definition to executions that use transactions in addition to locks and volatile variables for synchronization. We present a precise and efficient algorithm for dynamically verifying that an execution is free of data races. This algorithm generalizes the Goldilocks algorithm for data-race detectionby handling transactions and providing the ability to distinguish between read and write accesses. We have implemented our algorithm and the DataRaceException in the Kaffe Java Virtual Machine. We have evaluated our system on a variety of publicly available Java benchmarks and a few microbenchmarks that combine lock-based and transaction-based synchronization. Our experiments indicate that our implementation has reasonable overhead. Therefore, we believe that inaddition to being a debugging tool, the DataRaceException may be a viable mechanism to enforce the safety of executions of multithreaded Java programs.
Circuit-Switched Coherence
Authors: Natalie Enright Jerger, Mikko Lipasti, Li-Shiuan Peh
Venue: IEEE Computer Architecture Letters (2007)

Circuit-switched networks can significantly lower the communication latency between processor cores, when compared to packet-switched networks, since once circuits are set up, communication latency approaches pure interconnect delay. However, if circuits are not frequently reused, the long set up time and poorer interconnect utilization can hurt overall performance. To combat this problem, we propose a hybrid router design which intermingles packet-switched flits with circuit-switched flits. Additionally, we co-design a prediction-based coherence protocol that leverages the existence of circuits to optimize pair-wise sharing between cores. The protocol allows pair-wise sharers to communicate directly with each other via circuits and drives up circuit reuse. Circuit-switched coherence provides overall system performance improvements of up to 17% with an average improvement of 10% and reduces network latency by up to 30%.
Nomad: migrating OS-bypass networks in virtual machines
Authors: Wei Huang, Jiuxing Liu, Matthew Koop, Bulent Abali, Dhabaleswar Panda
Venue: Proceedings of the 3rd international conference on Virtual execution environments (2007)

Virtual machine (VM) technology is experiencing a resurgence due to various benefits including ease of management, security and resource consolidation. Live migration of virtual machines allows transparent movement of OS instances and hosted applications across physical machines. It is one of the most useful features of VM technology because it provides a powerful tool for effective administration of modern cluster environments. Migrating network resources is one of the key problems that need to be addressed in the VM migration process. Existing studies of VM migration have focused on traditional I/O interfaces such as Ethernet. However, modern high-speed interconnects with intelligent NICs pose significantly more challenges as they have additional features including hardware level reliable services and direct I/O accesses. In this paper we present Nomad, a design for migrating modern interconnects with the aforementioned features, focusing on cluster environments running VMs. We introduce a thin namespace virtualization layer to efficiently address location dependent resource handles and a handshake protocol which transparently maintains reliable service semantics during migration. We demonstrate our design by implementing a prototype based on the Xen virtual machine monitor and InfiniBand. Our performance analysis shows that Nomad can achieve efficient migration of network resources, even in environments with stringent communication performance requirements.
Multidimensional system simulation with functional transformations
Authors: R. Rabenstein
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 04 (1996)

The application of methods from multidimensional systems theory and digital signal processing opens new ways for the efficient simulation of time and space dependent problems like wave propagation or heat and mass transfer. The basic idea, is the application of suitably chosen functional transformations for the time and space coordinates. Initial and boundary conditions are considered in a systematic way. This leads to the structure of a discrete system which closely models the behaviour of the given continuous system and which is suitable for computer implementation. Numerical results show considerable savings in computer time over conventional finite difference methods.
Development of undergraduate online CS/IS course based on Web-lecturing technology
Authors: V. Uskov
Venue: Proceedings of the Frontiers in Education Conference, 2001. on 31st Annual - Volume 01 (2001)

Teaching and learning online through the Internet and World Wide Web (Web) are going to change the traditional paradigm of education and teaching and learning technologies. This motivated us, faculty of the Department of Computer Science and Information Systems, Bradley University (Peoria, IL, USA), propose and implement in 2000-2001 the project on a design and development of the Web-based CIS102 "Introduction to Computer Information Systems using Visual Basic" computer science course. It is based on the state-of-the-art: (a) Web-lecturing teaching technology; and (b) 'active learning' paradigm of education. This innovative project was aimed to: (1) introduce the Web-lecturing teaching technology and Web-based audio- and video- communication technologies to Bradley University students and faculty; (2) actively engage students into the 'active learning' paradigm of education; (3) stimulate professional development of Bradley faculty on Web-based instructional tools of the 3/sup rd/ generation; and (4) increase the quality of students' knowledge and skills in computer science/information systems areas.