ppxscal/embedding_network huggingface dataset:
Experiences with locking in a NUMA multiprocessor operating system kernel
Authors: Ronald C. Unrau, Orran Krieger, Benjamin Gamsa, Michael Stumm
Venue: Proceedings of the 1st USENIX conference on Operating Systems Design and Implementation (1994)

We describe the locking architecture of a new operating system, HURRICANE, designed for large scale shared-memory multiprocessors. Many papers already describe kernel locking techniques, and some of the techniques we use have been previously described by others. However, our work is novel in the particular combination of techniques used, as well as several of the individual techniques themselves. Moreover, it is the way the techniques work together that is the source of our performance advantages and scalability. Briefly, we use: • a hybrid coarse-grain/fine-grain locking strategy that has the low latency and space overhead of a coarse-grain locking strategy while having the high concurrency of a fine-grain locking strategy; • replication of data structures to increase access bandwidth and improve concurrency; • a clustered kernel that bounds the number of processors that can compete for a lock so as to reduce second order effects such as memory and interconnect contention; • Distributed Locks to further reduce second order effects, with modifications that reduce the uncontended latency of these locks to close to that of spin locks.
Privacy-preserving collaborative filtering
Authors: Wenliang Du
Venue:  (2006)

With the evolution of the Internet, collaborative filtering (CF) techniques are becoming increasingly popular. Such techniques are widely used by many E-commerce companies to suggest products to customers, based on like-minded customers' preferences; but they fail to protect users' privacy. Data from customers is gathered for recommendation purposes; however, collecting high quality data is not an easy task, due to privacy concerns. Since many users are worried about their privacy, they sometimes refuse to contribute their data; or occasionally they might decide to give false information. Producing accurate referrals based on insufficient data and/or false data is impossible. CF systems provide referrals on existing databases comprised of ratings recorded from groups of people evaluating various items; sometimes, however, the systems' ratings are split among different parties. To provide better filtering services, the parties may wish to share their data; but they may not want to disclose information of a private nature. We propose to use randomization techniques to protect users' privacy while still producing accurate referrals. We investigate providing predictions on memory- and model-based CF algorithms with privacy assured by using randomized perturbation techniques (RPT) in Chapter 3 and Chapter 4, respectively; while we show how to produce recommendations without violating users' privacy using randomized response techniques (RRT) in Chapter 5. In Chapter 6, we explore inconsistently disguised data-based CF with privacy provided by the RPT. When data owners wish to provide recommendations using a joint database without disclosing sensitive data to each other, they may achieve accurate privacy-preserving referrals on integrated data with schemes we have proposed. We investigate performing filtering tasks; including prediction generations and top- N recommendations, on vertically or horizontally partitioned data, with privacy preservation, in Chapter 7 and Chapter 8. We conduct various experiments using well-known existing data sets to evaluate the overall performance of our approaches. Furthermore, we analyze the effects of different parameters on accuracy and privacy. Finally, in Chapter 9, we present our results and explain future directions.
Internet Use by Hospice Families and Providers: A Review
Authors: Lia Willis, George Demiris, Debra Parker Oliver
Venue: Journal of Medical Systems (2007)

This literature review explores the current evidence related to use of the Internet by hospice patients or families and palliative care/hospice professionals. The research questions guiding this study pertain to the current Internet-based interventions in hospice and palliative care and the evidence of their effectiveness. Six studies were identified as a result of an extensive literature review. These studies included research about web-based clinical interventions for patients, and patients', caregivers' and hospice/palliative care providers' use of the Internet. The majority of interventions involve accessing information via the Internet. Participants among the studies included patients, caregivers/family members, and health care professionals. Findings overall indicate effectiveness of Internet-based interventions. Both patients and professionals are using the Internet to find answers to healthcare questions, communicate, and/or deliver healthcare interventions.
Influence of Dictionary Size on the Lossless Compression of Microarray Images
Authors: Robert Bierman, Rahul Singh
Venue: Proceedings of the Twentieth IEEE International Symposium on Computer-Based Medical Systems (2007)

A key challenge in the management of microarray data is the large size of images that constitute the output of microarray experiments. Therefore, only the expression values extracted from these experiments are generally made available. However, the extraction of expression data is effected by a variety of factors, such as the thresholds used for background intensity correction, method used for grid determination, and parameters used in foreground (spot)-background delineation. This information is not always available or consistent across experiments and impacts downstream data analysis. Furthermore, the lack of access to the image-based primary data often leads to costly replication of experiments. Currently, both lossy and lossless compression techniques have been developed for microarray images. While lossy algorithms deliver better compression, a significant advantage of the lossless techniques is that they guarantee against loss of information that is putatively of biological importance. A key challenge therefore is the development of more efficacious lossless compression techniques. Dictionary-based compression is one of the critical methods used in lossless microarray compression. However, the image-based microarray data has potentially infinite variability. So the selection and effect of the dictionary size on the compression rate is crucial. Our paper examines this problem and shows that increasing the dictionary size beyond a certain size, does not lead to better compression. Our investigations also point to strategies for determining the optimal dictionary size.
Frugality ratios and improved truthful mechanisms for vertex cover
Authors: Edith Elkind, Leslie Ann Goldberg, Paul W. Goldberg
Venue: Proceedings of the 8th ACM conference on Electronic commerce (2007)

In set-system auctions, there are several overlapping teams of agents, and a task that can be completed by any of these teams. The auctioneer's goal is to hire a team and pay as little as possible. Examples of this setting include shortest-path auctions and vertex-cover auctions. Recently, Karlin, Kempe and Tamir introduced a new definition of frugality ratio for this problem. Informally, the "frugality ratio" is the ratio of the total payment of a mechanism to a desired payment bound. The ratio captures the extent to which the mechanism overpays, relative to perceived fair cost in a truthful auction. In this paper, we propose a new truthful polynomial-time auction for the vertex cover problem and bound its frugality ratio. We show that the solution quality is with a constant factor of optimal and the frugality ratio is within a constant factor of the best possible worst-case bound; this is the first auction for this problem to have these properties. Moreover, we show how to transform any truthful auction into a frugal one while preserving the approximation ratio. Also, we consider two natural modifications of the definition of Karlin et al., and we analyse the properties of the resulting payment bounds, such as monotonicity, computational hardness, and robustness with respect to the draw-resolution rule. We study the relationships between the different payment bounds, both for general set systems and for specific set-system auctions, such as path auctions and vertex-cover auctions. We use these new definitions in the proof of our main result for vertex-cover auctions via a boot-strapping technique, which may be of independent interest.
Capstone senior design at the University of Alabama
Authors: J. Parker
Venue: Proceedings of the 26th Annual Frontiers in Education - Volume 01 (1996)

The mechanical engineering program at the University of Alabama has had a two-course capstone design sequence (the Design Clinic) since the late 1970's. Although several changes have been incorporated over the years, the use of external industry-sponsored projects has remained a constant. Students participate in a common, competitive design project during the first two-thirds of the first course (ME 489). During the last third of the first course and the entire second course (ME 490), each team of three or four students works on a single, extended external project. We focus on the extended design activity. The overall organization of the course sequence and projects, including faculty support options and the process used to select student project teams, is outlined. We describe our various sources of projects, along with some of the possible advantages and disadvantages of each. Financial considerations for the course sequence and the impact of finances on project selection are also covered. Finally, brief descriptions of several recent projects are given. Interested faculty members should be able to use these suggestions in the development of their own senior design courses.
The performance impact of traffic patterns on routing protocols in mobile ad hoc networks
Authors: Himabindu Pucha, Saumitra M. Das, Y. Charlie Hu
Venue: Computer Networks: The International Journal of Computer and Telecommunications Networking (2007)

As mobile ad hoc network (MANET) systems research has matured and several testbeds have been built to study MANETs, research has focused on developing new MANET applications such as collaborative games, collaborative computing, messaging systems, distributed security schemes, MANET middleware, peer-to-peer file sharing systems, voting systems, resource management and discovery, vehicular computing and collaborative education systems. The growing set of diverse applications developed for MANETs pose far more complex traffic patterns than the simple one-to-one traffic pattern, and hence the one-to-one traffic pattern widely used in previous protocol studies has become inadequate in reflecting the relative performance of these protocols when deployed to support these emerging applications. As a first step towards effectively supporting newly developed and future diverse MANET applications, this paper studies the performance impact of diverse traffic patterns on routing protocols in MANETs. Specifically, we propose a new communication model that extends the previous communication model to include a more general traffic pattern that varies the number of connections per source node. We study the performance impact of traffic patterns on various routing protocols via detailed simulations of an ad hoc network of 112 mobile nodes. Our simulation results show that many of the conclusions drawn in previous protocol comparison studies no longer hold under the new traffic patterns. These results motivate the need for performance evaluation of ad hoc networks to not only include rich and diverse mobility models as has been done in the past but also include diverse traffic patterns that stress a wide set of protocol design issues.
Implementing Parameterized Type Algorithm Definitions in Mathematica
Authors: Alina Andreica
Venue: Proceedings of the Eighth International Symposium on Symbolic and Numeric Algorithms for Scientific Computing (2006)

The paper focuses on means of defining parameterized type categories and algorithms built on such types in Mathematica. Symbolic algorithms based on category theory have the advantage of systematically dealing with domains, categories, operators over them by creating general contexts of expressing algorithms, which can be applied by parameterizing them with various domains, using the same algorithm definition. While similar approaches have been previously presented by the author, the present paper aims at a stronger focus on algorithm characteristics defined on categorical principles and giving a more general framework for implementing Mathematica algorithms based on generic principles and category theory. The paper also discusses run time efficiency aspects for these generic implementations.
Predicting locality phases for dynamic memory optimization
Authors: Xipeng Shen, Yutao Zhong, Chen Ding
Venue: Journal of Parallel and Distributed Computing (2007)

Dynamic data, cache, and memory adaptation can significantly improve program performance when they are applied on long continuous phases of execution that have dynamic but predictable locality. To support phase-based adaptation, this paper defines the concept of locality phases and describes a four-component analysis technique. Locality-based phase detection uses locality analysis and signal processing techniques to identify phases from the data access trace of a program; frequency-based phase marking inserts code markers that mark phases in all executions of the program; phase hierarchy construction identifies the structure of multiple phases; and phase-sequence prediction predicts the phase sequence from program input parameters. The paper shows the accuracy and the granularity of phase and phase-sequence prediction as well as its uses in dynamic data packing, memory remapping, and cache resizing.
Engineering Large-Scale Software-Intensive Systems
Authors: R. Geoff Dromey
Venue: Proceedings of the 2007 Australian Software Engineering Conference (2007)

There are four major threats to successfully building large-scale software-intensive systems: (1) a failure to control the complexity that arises during the development process (2) a failure to achieve early resolution of deficiencies in informal statements/knowledge of stakeholders' needs (3) failure to construct a system that satisfies stakeholders' needs, and (4) a failure to effectively organize the project team. All four of these threats can be very significantly reduced by making maximum and effective use of the requirements information that expresses stakeholders' needs. This is achieved by choosing a representation that supports rigorous formalization and composition of individual requirements one at a time into an integrated, state-based, graphical view. It amounts to building a system 'out of' its requirements. The justification for, the processes, representations and results of applying this constructive approach to tackling the core problems associated with developing large-scale, dependable systems will be presented.
Parallel Computation of Skyline Queries
Authors: Adan Cosgaya-Lozano, Andrew Rau-Chaplin, Norbert Zeh
Venue: Proceedings of the 21st International Symposium on High Performance Computing Systems and Applications (2007)

Skyline queries have received considerable attention in the database community recently. The goal is to retrieve all records in a database that have the property that no other record is better according to all of a given set of criteria. While this problem has been well studied in the computational geometry literature, the solution of this problem in the database context requires techniques designed particularly to handle large amounts of data. In this paper, we show that parallel computing is an effective method to speed up the answering of skyline queries on large data sets. We also propose to preprocess the set of data points to quickly answer subsequent skyline queries on any subset of the dimensions.
QoS-aware model driven architecture through the UML and CIM
Authors: Kenneth Chan, Iman Poernomo
Venue: Information Systems Frontiers (2007)

The specification of Quality of Service (QoS) constraints over software design requires measures that ensure such requirements are met by the delivered product. Achieving this goal is non-trivial, as it involves, at least, identifying how QoS constraint specifications should be checked at the runtime. In this paper we present an implementation of a Model Driven Architecture (MDA) based framework for the runtime monitoring of QoS properties. We incorporate the UML2 superstructure and the UML profile for Quality of Service to provide abstract descriptions of component-and-connector systems. We then define transformations that refine the UML2 models to conform with the Distributed Management Taskforce (DMTF) Common Information Model (CIM) (Distributed Management Task Force Inc. 2006), a schema standard for management and instrumentation of hardware and software. Finally, we provide a mapping the CIM metamodel to a .NET-based metamodel for implementation of the monitoring infrastructure utilising various .NET features including the Windows Management Instrumentation (WMI) interface.
Continuously maintaining order statistics over data streams: extended abstract
Authors: Xuemin Lin
Venue: Proceedings of the eighteenth conference on Australasian database - Volume 63 (2007)

A rank query is essentially to find a data element with a given rank against a monotonic order specified on data elements. It has several equivalent variations [8, 17, 30]. Rank queries over data streams have been investigated in the form of quantile computation. A &phis;-quantile (&phis; &isin; (0,1]) of a collection of N data elements is the element with rank [&phis;N] against a monotonic order specified on data elements. Rank and quantile queries have many applications [1, 3, 6, 7, 10, 14-16, 26, 27], including monitoring high speed networks, trends and fleeting opportunities detection in the stock market, sensor data analysis, Web ranking aggregation and log mining, etc. In these applications, they not only play very important roles in the decision making but also have been used in summarizing data distributions of data streams. The following example shows a popular tool to compare the distributions of two data sets (data streams).
A beamspace-time RAKE receiver for sectored CDMA systems
Authors: Ta-Sung Lee
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 05 (2000)

A beamspace-time (BT) RAKE receiver is proposed for multiple access interference (MAI) suppression and multipath diversity reception in sectored wireless CDMA communications. The scheme involves two stages. First, a set of diversity beamformers is constructed and then combined for each finger which provides effective reception of in-sector signals and suppression of out-of-sector MAI. Second, an adaptive correlator is attached to each combined beam to combat in-sector MAI and collect signal multipaths in a coherent manner. The proposed BT RAKE receiver is blind in that no training signal is required. The only information required is the signature sequence, timing and a rough estimate of the angle of arrival (AOA) of the signal.
Modeling and Evolving Crosscutting Concerns in ADORA
Authors: Silvio Meier, Tobias Reinhard, Reinhard Stoiber, Martin Glinz
Venue: Proceedings of the 29th International Conference on Software Engineering Workshops (2007)

For an effective handling of crosscutting concerns during the software process, adequate support is required not only in design and coding, but also in requirements engineering. For this purpose, we have developed an aspectoriented extension of the requirements modeling language ADORA. In this paper, we present an extension of our approach which makes it capable of supporting the evolution of aspect-oriented requirements models for both functional and non-functional aspects.
Implementation of a Formal Security Policy Refinement Process in WBEM Architecture
Authors: Romain Laborde, Michel Kamel, François Barrère, Abdelmalek Benzekri
Venue: Journal of Network and Systems Management (2007)

Security mechanisms enforcement consists in configuring devices with the aim that they cooperate and guarantee the defined security goals. In the network context, this task is complex due to the number, the nature, and the interdependencies of the devices to consider.In previous papers, we have proposed a formal framework that focuses on network security information management refinement. The framework includes three abstraction levels: the network security objectives, the network security tactics, and the network security device configurations. The information models of each abstraction level (consistency, correctness and feasibility) are formally specified and analyzed.In this paper we present the integration of this formal refinement process in the WBEM initiative in order to provide a management infrastructure that guarantees the validity of the deployed security configurations.
Theoretical and Computational Issues of Optimal Control for Distributed Hopfield Neural Network Equations with Diffusion Term
Authors: Quan-Fang Wang
Venue: SIAM Journal on Scientific Computing (2007)

This work investigates theoretical and computational issues of optimal control for distributed Hopfield neural network equations with diffusion term. Due to introducing a diffusion term in our model, a theoretical conclusion is deduced for the control of the nonlinear parabolic partial differential equation in the framework of variational methods (cf. [J. L. Lions, Optimal Control of Systems Governed by Partial Differential Equations, Springer-Verlag, Berlin, Heidelberg, New York, 1971]) by means of distributed control, boundary control, and initial control. Experimental demonstration is implemented via a semidiscrete numerical algorithm based on the finite element method. The theoretical results are verified using the proposed scheme.
Decoding of text lines in grayscale document images
Authors: K. Popat
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2001. on IEEE International Conference - Volume 03 (2001)

The Document Image Decoding (DID) framework for recognizing printed text in images has been shown in previous work to achieve extremely high recognition accuracy when its models are well matched to the data. To date, DID has been restricted to binary images, in part for computational reasons, and in part because binary scanning is widely available and often of sufficient spatial resolution to make the use of grayscale information unnecessary for reliable recognition. Advances in computer speed and memory, along with the emergence of low-cost digital still cameras and similar devices as alternatives to traditional scanners, motivates the extension of the DID formalism to the low-spatial-resolution grayscale and color domains. To do so requires substantially generalizing DID's image-formation and degradation models. This paper lays out an approach and presents preliminary results on real data.
Area and Power Efficient Synthesis of DPA-Resistant Cryptographic S-Boxes
Authors: Matteo Giaconia, Marco Macchetti, Francesco Regazzoni, Kai Schramm
Venue: Proceedings of the 20th International Conference on VLSI Design held jointly with 6th International Conference: Embedded Systems (2007)

This paper presents a novel design methodology for the hardware implementation of non-linear bijective functions, commonly used in most symmetric-key cryptographic algorithms and known as substitution boxes (S-boxes). The proposed technique thwarts a particularly relevant class of side-channel attacks against cryptographic hardware, that of differential power analysis attacks (DPA). In the proposed approach, the cost of the countermeasure is kept low in terms of silicon process overheads (standard CMOS gates used), area requirement, power consumption and latency, when compared to existing countermeasures. Its effectiveness is proven by showing resistance to simulated DPA attacks using power curves derived with SPICE simulation.