ppxscal/embedding_network huggingface dataset:
Hardware acceleration in commercial databases: a case study of spatial operations
Authors: Nagender Bandi, Chengyu Sun, Divyakant Agrawal, Amr El Abbadi
Venue: Proceedings of the Thirtieth international conference on Very large data bases - Volume 30 (2004)

Traditional databases have focused on the issue of reducing I/O cost as it is the bottleneck in many operations. As databases become increasingly accepted in areas such as Geographic Information Systems (GIS) and Bioinformatics, commercial DBMS need to support data types for complex data such as spatial geometries and protein structures. These non-conventional data types and their associated operations present new challenges. In particular, the computational cost of some spatial operations can be orders of magnitude higher than the I/O cost. In order to improve the performance of spatial query processing, innovative solutions for reducing this computational cost are beginning to emerge. Recently, it has been proposed that hard-ware acceleration of an off-the-shelf graphics card can be used to reduce the computational cost of spatial operations. However, this proposal is preliminary in that it establishes the feasibility of the hardware assisted approach in a stand-alone setting but not in a real-world commercial database. In this paper we present an architecture to show how hardware acceleration of an off-the-shelf graphics card can be integrated into a popular commercial database to speed up spatial queries. Extensive experimentation with real-world datasets shows that significant improvement in the performance of spatial operations can be achieved with this integration. The viability of this approach underscores the significance of a tighter integration of hardware acceleration into commercial databases for spatial applications.
Labels and event processes in the Asbestos operating system
Authors: Steve Vandebogart, Petros Efstathopoulos, Eddie Kohler, Maxwell Krohn, Cliff Frey, David Ziegler, Frans Kaashoek, Robert Morris, David Mazières
Venue: ACM Transactions on Computer Systems (TOCS) (2007)

Asbestos, a new operating system, provides novel labeling and isolation mechanisms that help contain the effects of exploitable software flaws. Applications can express a wide range of policies with Asbestos's kernel-enforced labels, including controls on interprocess communication and system-wide information flow. A new event process abstraction defines lightweight, isolated contexts within a single process, allowing one process to act on behalf of multiple users while preventing it from leaking any single user's data to others. A Web server demonstration application uses these primitives to isolate private user data. Since the untrusted workers that respond to client requests are constrained by labels, exploited workers cannot directly expose user data except as allowed by application policy. The server application requires 1.4 memory pages per user for up to 145,000 users and achieves connection rates similar to Apache, demonstrating that additional security can come at an acceptable cost.
Molecular Surface Abstraction
Authors: Gregory Cipriano
Venue: IEEE Transactions on Visualization and Computer Graphics (2007)

In this paper we introduce a visualization technique that provides an abstracted view of the shape and spatio-physico-chemical properties of complex molecules. Unlike existing molecular viewing methods, our approach suppresses small details to facilitate rapid comprehension, yet marks the location of significant features so they remain visible. Our approach uses a combination of filters and mesh restructuring to generate a simplified representation that conveys the overall shape and spatio-physico-chemical properties (e.g. electrostatic charge). Surface markings are then used in the place of important removed details, as well as to supply additional information. These simplified representations are amenable to display using stylized rendering algorithms to further enhance comprehension. Our initial experience suggests that our approach is particularly useful in browsing collections of large molecules and in readily making comparisons between them.
Adaptability of Just-in-time (JIT) Philosophy to Service Systems: A Case Study
Authors: Deniz Balci, Saadettin Erhan Kesen, Ömer Faruk Baykoç
Venue: Simulation (2007)

Although a great deal of successful research has been carried out in just-in-time (JIT) philosophy, few researchers have focused on the adaptation of JIT philosophy in service systems. Despite the recent improvements in the service systems, few studies have been carried out which eXamine the effects of the JIT philosophy on service systems which have a different structure to production systems. As a result of the benefits obtained from successful application of the JIT philosophy in the production systems, we have adapted the JIT philosophy for the service systems and eXamined the obtainable benefits. For this purpose, observation and time-scaling studies were made in an Adult Emergency Service in Turkey. Within the framework of the data acquired in this study, the eXisting system was modeled. By analyzing the simulation results, an alternative system has been proposed which can be applied to the system. Results show that the proposed system under the principle of JIT philosophy outperforms the eXisting system.
Applying a cryptographic scheme in the RPINA protocol
Authors: Giannakis Antoniou, Ana Jancic, Udaya Parampalli, Leon Sterling
Venue: Proceedings of the Second International Workshop on Digital Forensics and Incident Analysis (2007)

The Respect Private Information of Non Abusers (RPINA) protocol allows users to communicate anonymously while the corresponding server ensures that the identity of the user will be revealed by a third party, called Directory Service (DS), should the user attempt a malicious attack. However, malicious co-operation between the server and the DS is the major vulnerability of the RPINA protocol. In this paper we introduce a technique, which decrease this vulnerability.
Privacy preserving data mining of sequential patterns for network traffic data
Authors: Seung-Woo Kim, Sanghyun Park, Jung-Im Won, Sang-Wook Kim
Venue: Information Sciences: an International Journal (2008)

As the total amount of traffic data in networks has been growing at an alarming rate, there is currently a substantial body of research that attempts to mine traffic data with the purpose of obtaining useful information. For instance, there are some investigations into the detection of Internet worms and intrusions by discovering abnormal traffic patterns. However, since network traffic data contain information about the Internet usage patterns of users, network users' privacy may be compromised during the mining process. In this paper, we propose an efficient and practical method that preserves privacy during sequential pattern mining on network traffic data. In order to discover frequent sequential patterns without violating privacy, our method uses the N-repository server model, which operates as a single mining server and the retention replacement technique, which changes the answer to a query probabilistically. In addition, our method accelerates the overall mining process by maintaining the meta tables in each site so as to determine quickly whether candidate patterns have ever occurred in the site or not. Extensive experiments with real-world network traffic data revealed the correctness and the efficiency of the proposed method.
Adapting Superpeer Size Using Particle Swam Optimization for Self-Organizing Superpeer Ring with Loosely Consistent DHT
Authors: Saeyoung Han, Sungyong Park
Venue: Proceedings of the 7th IEEE International Conference on Computer and Information Technology (2007)

A superpeer size adaptation using PSO is proposed for the self-organizing superpeer ring with loosely- consistent DHT. In the proposed scheme, all peers memorize the superpeer ratio where they or their neighbors experienced the best response time and adjust the superpeer ratio autonomously using PSO algorithm. Without tuning the optimal superpeer ratio value manually, the self-organizing superpeer ring can maintain moderately good response time in dynamic peer-to-peer systems.
Highlights of the 1974 Lake Arrowhead Workshop
Authors: W. F. Ross
Venue: Computer (1975)

The dramatic decline in computer hardware costs in recent years has brought the costs of software development into sharp focus. But important efforts to address software technology have been underway during the same period-notably in the 60's by Böhm, Jacopini, Dijkstra, Parnas, and others in the university environment, and in the 70's by such people as Mills and Baker, who defined specific elements of a methodology directed toward reducing software costs and improving software quality. This methodology, which according to Mills and Baker was successfully applied to the New York Times information bank project, is generally referred to as structured programming (SP)-but includes such methods as top down design and chief programmer teams. 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
Wide-scale botnet detection and characterization
Authors: Anestis Karasaridis, Brian Rexroad, David Hoeflin
Venue: Proceedings of the first conference on First Workshop on Hot Topics in Understanding Botnets (2007)

Malicious botnets are networks of compromised computers that are controlled remotely to perform large-scale distributed denial-of-service (DDoS) attacks, send spam, trojan and phishing emails, distribute pirated media or conduct other usually illegitimate activities. This paper describes a methodology to detect, track and characterize botnets on a large Tier-1 ISP network. The approach presented here differs from previous attempts to detect botnets by employing scalable non-intrusive algorithms that analyze vast amounts of summary traffic data collected on selected network links. Our botnet analysis is performed mostly on transport layer data and thus does not depend on particular application layer information. Our algorithms produce alerts with information about controllers. Alerts are followed up with analysis of application layer data, that indicates less than 2% false positive rates.
Practical suffix tree construction
Authors: Sandeep Tata, Richard A. Hankins, Jignesh M. Patel
Venue: Proceedings of the Thirtieth international conference on Very large data bases - Volume 30 (2004)

Large string datasets are common in a number of emerging text and biological database applications. Common queries over such datasets include both exact and approximate string matches. These queries can be evaluated very efficiently by using a suffix tree index on the string dataset. Although suffix trees can be constructed quickly in memory for small input datasets, constructing persistent trees for large datasets has been challenging. In this paper, we explore suffix tree construction algorithms over a wide spectrum of data sources and sizes. First, we show that on modern processors, a cache-efficient algorithm with O(n2) complexity outperforms the popular O(n) Ukkonen algorithm, even for in-memory construction. For larger datasets, the disk I/O requirement quickly becomes the bottleneck in each algorithm's performance. To address this problem, we present a buffer management strategy for the O(n2) algorithm, creating a new disk-based construction algorithm that scales to sizes much larger than have been previously described in the literature. Our approach far outperforms the best known disk-based construction algorithms.
Knowledge management system for electronic learning of IT skills
Authors: Chi-Hong Leung, Yuen-Yan Chan
Venue: Proceedings of the 8th ACM SIGITE conference on Information technology education (2007)

Other than the traditional classroom-based learning in which students learn from the teacher directly, students should share their knowledge with others to facilitate the learning process. The application of the information technologies creates a common, user-friendly, and universally accessible learning platform that should not only focus on providing access to information and expertise, but also embrace a far richer architecture of online resources. Knowledge management includes the capability to collect, archive, manage, evaluate, and distribute information across the learning community. In the learning process, a student may like to share knowledge with other students and learn from them. After doing some exercises, students can learn and reflect on these practices. They recognize rules and patterns in practice. The paper presents a web-based knowledge management system. It is used to facilitate students' learning of some practical IT skills such as programming. The system can provide ways for students to communicate on a regular basis. It brings instantaneous and real-time information and expertise to students. Knowledge management defines electronic learning in ways that make it more acceptable and more a part of learning culture than an adjunct to it. It is the key to the success of electronic learning. It is found that collaborative knowledge creation and sharing can be supported by the system. Its success is dependent on a number of factors: students' engagement, familiarity of the technology and careful class plan design. It is also found that electronic learning is not to replace traditional learning taken place in classrooms. Knowledge is the most serious resource for future social and economic development. Online education is an answer to solving some problems of education today. To students of this new era, it is empowering tools helping them to equip themselves to adapt to increasing complexities of such knowledge society.
Secure Routing for Mobile Ad Hoc Networks
Authors: Jing Liu, Fei Fu, Junmo Xiao, Yang Lu
Venue: Proceedings of the Eighth ACIS International Conference on Software Engineering, Artificial Intelligence, Networking, and Parallel/Distributed Computing - Volume 03 (2007)

Buttyan found out a security flaw in Ariadne^[10] and proposed a secure routing protocol, EndairA^[19-20], with the ability to resist active-1-1 attacks. But unfortunately we discover an as yet unknown active-0- 1 attack which we call man-in-the-middle attack and EndairA couldn't resist. Accordingly we propose a new secure routing protocol, EndairALoc. Analysis shows that EndairALoc can resist not only active-1-1 attacks but also the wormhole attack. Furthermore EndairALoc uses pairwise secret keys instead of public keys used in EndairA. Compared with EndairA, EndairALoc can save more energy in the routing establishment..
Program Testing
Authors: E. F. Miller
Venue: Computer (1978)

Nearly everyone in the computer business is concerned about quality. It's probably fair to say there'll be a pot of gold or its currency equivalent awaiting the first person to figure out how to package up some "software quality" and provide it in large quantities at substantial OEM discounts!
Note: Cyclically permutable representations of cyclic codes
Authors: Derek H. Smith, Stephanie Perkins
Venue: Discrete Applied Mathematics (2008)

Cyclically permutable codes have been studied for several applications involving synchronization, code-division multiple-access (CDMA) radio systems and optical CDMA. The usual emphasis is on finding constant weight cyclically permutable codes with the maximum number of codewords. In this paper the question of when a particular error-correcting code is equivalent (by permutation of the symbols) to a cyclically permutable code is addressed. The problem is introduced for simplex codes and a motivating example is given. In the final section it is shown that the construction technique may be applied in general to cyclic codes.
A Polite Policy for Revisiting Web Pages
Authors: Criston Souza, Eduardo Laber, Caio Valentim, Eduardo Cardoso
Venue: Proceedings of the 2007 Latin American Web Conference (2007)

We propose and analyze an efficient scheduling policy for revisiting web pages so as to keep a local repository as up to date as possible. The main contribution of our policy is the fact that it takes into account the politeness constraint in order to compute the revisiting times. Our experiments suggest that the performance of our policy is very close to the optimal one and that it is significantly better than the one obtained using a reasonable variation of the policy proposed in [Wolf et. al., WWW 2002].
Automatic dynamic run-time optical network reservations
Authors: J. R. Lange, A. I. Sundararaj, P. A. Dinda
Venue: Proceedings of the High Performance Distributed Computing, 2005. HPDC-14. Proceedings. 14th IEEE International Symposium (2005)

Optical networking may dramatically change high performance distributed computing. One reason is that optical networks can support provisioning dynamically configurable lightpaths, a form of circuit switching, through reservations. However, to use it (and all other network reservation mechanisms), the user or developer must modify the application. We present a system, VRESERVE, that automatically and dynamically creates network reservation requests based on the inferred network demands of running distributed and/or parallel applications with no modification to the application or operating system, and no input from the user or developer. Our execution model is a collection of virtual machines interconnected by an overlay network. The overlay network infers application demands, providing a dynamic run-time assessment of the application's topology and traffic load matrix. We then reserve lightpaths corresponding to the topology and use the overlay to forward virtual network traffic over them. We evaluate our system on the OMNInet network.
A New Control Method Based on Flexible Logic
Authors: Lihua Fu, Huacan He
Venue: Proceedings of the Fourth International Conference on Fuzzy Systems and Knowledge Discovery - Volume 01 (2007)

Fuzzy control is based on fuzzy control rules, provided by experts, to control complex systems. The fuzzy control rules describe rudely the relation between input and output of controller. So Fuzzy controller is in essence a piecewise approximator. As a result, fuzzy control has two shortcomings in the process of controlling some practical complex systems. One is that control rules will increase exponentially with the creasing of the number of inputs, and the other one is that the precision of control system is not high. By analyzing thoroughly the essential relation between two input variables of the normal two-dimensional fuzzy controller, this paper proves that the essential relation is just universal combinatorial relation in Universal Logic. So the simple universal combinatorial operation can be used instead of complex fuzzy reasoning process. As a result, a flexible logic control method is proposed to realize the accurate control for complex system. Finally, the experimental result of single inverted-pendulum physical system has proved the correctness and effectiveness of the control method.
Brief paper: Adaptive output feedback control of general MIMO systems using multirate sampling and its application to a cart-crane system
Authors: Ikuro Mizumoto, Tongwen Chen, Satoshi Ohdaira, Makoto Kumon, Zenta Iwai
Venue: Automatica (Journal of IFAC) (2007)

In adaptive output feedback control based on almost strictly positive real conditions, a technical difficulty arises when the multi-input multi-output (MIMO) system under consideration is non-square, and in particular, has less inputs than outputs. To overcome this, we propose the idea of multirate sampled-data control-by carefully choosing faster input sampling rates, we obtain a lifted discrete-time system, which has the same number of inputs and outputs and does not give rise to the causality constraint. The adaptive control strategy is then applied to the lifted system, resulting in a multirate adaptive output feedback controller which is implementable digitally and provides closed-loop stability under certain conditions. The results reported here are validated on an experimental cart-crane system.
Physical Structure Segmentation with Projection Profile for Mathematic Formulae and Graphics in Academic Paper Images
Authors: Tzu-Yuan CHANG, Yusuke TAKIGUCHI, Minoru OKADA
Venue: Proceedings of the Ninth International Conference on Document Analysis and Recognition - Volume 02 (2007)

Image segmentation is an essential topic in a document processing system, and also is an important initial task for higher level image processing such as recognition or object tracking since recent years. In this paper we propose a method for segmentation and extraction of the regions of mathematical formulae and graphics in an academic paper. First, an academic paper image is transformed into a binary image by Ohtsu's method. Second, the boundary blank spaces of the binary image are removed and then the image is recursively segmented and extracted by vertical and horizontal projection profiles. We apply the proposed method to 150 academic paper images, and show that the method is adaptable, robust and effective for segmentation.
Tightly-Coupled Multi-Layer Topologies for 3-D NoCs
Authors: Hiroki Matsutani, Michihiro Koibuchi, Hideharu Amano
Venue: Proceedings of the 2007 International Conference on Parallel Processing (2007)

Three-dimensional Network-on-Chip (3-D NoC) is an emerging research topic exploring the network architecture of 3-D ICs that stack several smaller wafers for reducing wire length and wire delay. Although the network topology of 3-D NoC has been explored for a couple of years, there is still only a narrow range of choices. In this paper, we propose a class of 3-D topologies called Xbar-connected Network-on-Tiers (XNoTs), which consist of multiple network layers tightly connected via crossbar switches. To make the best use of the short delay and high density of inter-wafer links, XNoTs topologies have crossbar switches that connect different layers and their cores. The planar topology on every layer can be independently customized so as to meet the cost-performance requirements, as far as network connectivity is at least guaranteed with the bottom layer. We also propose their routing algorithm, which guarantees deadlock-freedom by restricting the inter-layer packet transfer from a lower-numbered layer to a higher-numbered layer. Path sets at the bottom layer close to the heat sink of the chip can be selectively employed in order to mitigate the heat-dissipation problem of 3-D ICs. Several forms of XNoTs topologies including meshes, tori, and/or trees are created, and they are evaluated in terms of performance, cost, and energy consumption. As a result, we show that even with the flexibilities mentioned above, XNoTs achieve at least as high throughput as existing 3-D topologies for equivalent chip sizes.