ppxscal/embedding_network huggingface dataset:
Optimal combination of sampled network measurements
Authors: Nick Duffield, Carsten Lund, Mikkel Thorup
Venue: Proceedings of the 5th ACM SIGCOMM conference on Internet Measurement (2005)

IP network traffic is commonly measured at multiple points in order that all traffic passes at least one observation point. The resulting measurements are subsequently joined for network analysis. Many network management applications use measured traffic rates (differentiated into classes according to some key) as their input data. But two factors complicate the analysis. Traffic can be represented multiple times in the data, and the increasing use of sampling during measurement means some classes of traffic may be poorly represented. In this paper, we show how to combine sampled traffic measurements in way that addresses both of the above issues. We construct traffic rate estimators that combine data from different measurement datasets with minimal or close to minimal variance. This is achieved by robust adaptation to the estimated variance of each constituent. We motivate the method with two applications: estimating the interface-level traffic matrix in a router, and estimating network-level flow rates from measurements taken at multiple routers.
Noise-proofing the doubly SH-projected coefficients for synthesizing images under environment lighting
Authors: Ping-Man Lam, Tze-Yui Ho, Chi-Sing Leung, Tien-Tsin Wong
Venue: Image Communication (2007)

The brute-force way to synthesize images of an object under various lighting environments is very time consuming. To speed up the synthesizing process, we can model the bidirectional reflectance distribution function (BRDF) of each surface element as a spherical harmonic (SH) coefficient matrix based on the double SH projection. With the SH coefficient matrices of all surface elements, we can relight an object under the global illumination. However, applying the classical least square method for the double SH projection, the returned SH coefficients are prohibitively large in magnitude because samples are available on the upper hemisphere only. Hence, the synthesizing process is very sensitive to small quantization noise introduced by the compression process. Existing methods to this noise-sensitivity problem mainly focus on the single SH projection. It should be noticed that the double SH projection further amplifies the artifacts. Straightforwardly extending existing methods to the double SH projection may not be theoretically nor practically feasible. In this paper, we present a robust estimation method for the double SH projection. With the proposed method, severe artifacts in synthesized images can be significantly reduced. Comparison with the existing Sloan's method is performed to support the effectiveness of the proposed method.
Facilitating interdisciplinary design education through case histories
Authors: P. S. Chinowsky, J. Robinson
Venue: Proceedings of the Frontiers in Education Conference, on 1995. Proceedings., 1995 - Volume 02 (1995)

The design and engineering professions are characterized by multifaceted, interdisciplinary problems requiring teams comprised of architects, engineers, and constructors. The unique attributes of individual locations, regulatory requirements, and owner preferences require interdisciplinary teams to cooperate throughout the design and building process to ensure that all requirements are satisfied. In contrast to this professional environment, engineering and design educational environments are characterized by strict disciplinary boundaries. Minimal interaction occurs within the educational framework of the engineering or design curriculum. This paper introduces one approach to reducing these boundaries and introducing interdisciplinary tools into design education. The paper introduces an interdisciplinary research effort being conducted at Georgia Tech to create comprehensive, interdisciplinary case studies highlighting the diverse participants required to complete a complex building project. Complementing this effort is the development of a computer-based environment with the capability to both present case histories to interdisciplinary teams of students in multiple formats and provide the flexibility to support individual student exploration. Finally, the paper addresses the challenges and issues facing the design and engineering education community in the process of integrating interdisciplinary educational experiences into a traditionally segregated educational curriculum.
Evolving spring-mass models: a test-bed for graph encoding schemes
Authors: S. Lucas
Venue: Proceedings of the Evolutionary Computation on 2002. CEC '02. Proceedings of the 2002 Congress - Volume 02 (2002)

For many interesting design problems the solution is most naturally represented as a type of graph. This paper proposes that the problem of evolving spring-mass models for a set of design challenges makes an excellent test-bed for evaluating the performance of various graph encoding schemes. We describe how the problem is set up, and introduce a planar graph coding scheme. Results demonstrate that the planar graph encoding scheme significantly outperforms a simple direct encoding scheme on a height-challenge design problem.
Ray-based analysis of a time-reversal mirror for underwater acoustic communication
Authors: J. Gomes
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 05 (2000)

Phase conjugation is a process whereby waves may be focused in an inhomogeneous and poorly characterized medium. Its application in underwater acoustics offers innovative solutions to active transmission problems, such as underwater digital communications. In this paper, the operation of a phase conjugate array is examined under simplified conditions, so that closed-form expressions for the pressure field may be obtained. These provide both insight into the energy focusing effect, and guidelines for designing actual arrays. Numerical results show that, from a communications perspective, signal regeneration at the focus offers significant intersymbol interference reduction. Equalization requirements at the receiver may therefore be substantially relaxed.
Designing a portable technical literacy course for use in California
Authors: K. Disney, S. Vitkovits, R. Pam
Venue: Proceedings of the Frontiers in Education Conference, on 1995. Proceedings., 1995 - Volume 02 (1995)

Summary form only given. The project discussed has developed a technical literacy course for a non-technical population of students. The focus is to draw examples of engineering systems from the local community so that students already have a "users" understanding of presented systems. First the students explore and study how a particular system works (i.e. how local bridges support loads), and then the basic science is introduced as needed to support the understanding of the application. Demonstrations, hands-on exercises, and tours of local engineering systems are used to engage the students. The course ideas are portable since all colleges have some examples of engineering systems locally.
Compositional Logical Semantics for Business Process Languages
Authors: Mihhail Matskin, Riina Maigre, Enn Tyugu
Venue: Proceedings of the Second International Conference on Internet and Web Applications and Services (2007)

In this paper we propose a compositional logical semantics for business process languages to be used in automatic Web service composition. We introduce a concept of Higher Order Work Flow (HOWF) and use it for expressing control of business process. A precise semantics of HOWF enables us both to dynamically generate HOWF for automatic composition of services and to reason about the reachability of goals in process models when HOWF are described manually. Our semantics is general enough to cover different process languages; however, we mainly show its applicability in the context of OWL-S and BPEL.
An improved traffic modeling scheme for MPEG video over content delivery networks
Authors: Chu-Chuan Lee, Chin-Wei Lin, Pao-Chi Chang
Venue: Proceedings of the The 8th International Conference on Communication Systems - Volume 02 (2002)

We propose an improved video traffic modeling scheme, delay-tolerant multi-leaky-bucket (DTMLB), for video streaming applications over the Internet. Based on the original multi-leaky-bucket modeling method (MLB), DTMLB parameterizes the actual traffic cumulative function instead of the empirical envelope function used by MLB. Moreover, DTMLB incorporates different delay tolerance characteristics among I-frames, P-frames, and B-frames of video to improve the overall bandwidth utilization. Simulation results show that DTMLB provides higher modeling accuracy and higher bandwidth utilization than the MLB and the peak rate modeling methods do. Furthermore, in our simulations, DTMLB generates the least burst traffic into the subsequent nodes of networks among all three methods tested.
Real-time detection of malicious network activity using stochastic models
Authors: Hari Balakrishnan
Venue:  (2006)

This dissertation develops approaches to rapidly detect malicious network traffic including packets sent by portscanners and network worms. The main hypothesis is that stochastic models capturing a host's particular connection-level behavior provide a good foundation for identifying malicious network activity in real-time. Using the models, the dissertation shows that a detection problem can be formulated as one of observing a particular "trajectory" of arriving packets and inferring from it the most likely classification for the given host's behavior. This stochastic approach enables us not only to estimate an algorithm's performance based on the measurable statistics of a host's traffic but also to balance the goals of promptness and accuracy in detecting malicious network activity. This dissertation presents three detection algorithms based on Wald's mathematical framework of sequential analysis. First, Threshold Random Walk (TRW) rapidly detects remote hosts performing a portscan to a target network. TRW is motivated by the empirically observed disparity between the frequency with which connections to newly visited local addresses are successful for benign hosts vs. for portscanners. Second, it presents a hybrid approach that accurately detects scanning worm infections quickly after the infected local host begins to engage in worm propagation. Finally, it presents a targeting worm detection algorithm, Rate-Based Sequential Hypothesis Testing (RBS), that promptly identifies high-fan-out behavior by hosts (e.g., targeting worms) based on the rate at which the hosts initiate connections to new destinations. RBS is built on an empirically-driven probability model that captures benign network characteristics. It then presents RBS+TRW, a unified framework for detecting fast-propagating worms independently of their target discovery strategy. All these schemes have been implemented and evaluated using real packet traces collected from multiple network vantage points. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
Algorithmic and Complexity Issues of Three Clustering Methods in Microarray Data Analysis
Authors: Jinsong Tan, Kok Seng Chua, Louxin Zhang, Song Zhu
Venue: Algorithmica (2007)

The complexity, approximation and algorithmic issues of several clustering problems are studied. These non-traditional clustering problems arise from recent studies in microarray data analysis. We prove the following results. (1) Two variants of the Order-Preserving Submatrix problem are NP-hard. There are polynomial-time algorithms for the Order-Preserving Submatrix problem when the condition or gene sets are fixed. (2) Three variants of the Smooth Clustering problem are NP-hard. The Smooth Subset problem is approximable with ratio 0.5, but it cannot be approximable with ratio 0.5 + &#x03b4; for any &#x03b4; > 0 unless NP = P. (3) The inferring plaid model problem is NP-hard.
Modeling nonlinear systems with cellular neural networks
Authors: F. Puffer
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1996. on Conference Proceedings., 1996 IEEE International Conference - Volume 06 (1996)

A learning procedure for the dynamics of cellular neural networks (CNN) with nonlinear cell interactions is presented. It is applied in order to find the parameters of CNN that model the dynamics of certain nonlinear systems, which are characterized by partial differential equations (PDEs). Values of a solution of the considered PDEs for a particular initial condition are taken as the training pattern at only a small number of points in time. Our results demonstrate that CNN obtained with our method approximate the dynamical behaviour of various nonlinear systems accurately. Results for two nonlinear PDEs, the /spl Phi//sup 4/-equation and the sine-Gordon equation, are discussed in detail.
On the design of coordination diagnosis algorithms for teams of situated agents
Authors: Meir Kalech, Gal A. Kaminka
Venue: Artificial Intelligence (2007)

Teamwork demands agreement among team-members in order to collaborate and coordinate effectively. When a disagreement between teammates occurs (due to failures), team-members should ideally diagnose its causes, to resolve the disagreement. Such diagnosis of social failures can be expensive in communication and computation, challenges which previous work has not addressed. We present a novel design space of diagnosis algorithms, distinguishing several phases in the diagnosis process, and providing alternative algorithms for each phase. We then combine these algorithms in different ways to empirically explore specific design choices in a complex domain, on thousands of failure cases. The results show that different phases of diagnosis affect communication and computation overhead. In particular, centralizing the diagnosis disambiguation process is a key factor in reducing communications, while runtime is affected mainly by the amount of reasoning about other agents. These results contrast with previous work in disagreement detection (without diagnosis), in which distributed algorithms reduce communications.
High-speed processing and high-reliability technology in an integrated fixed-line and wireless, autonomous decentralized IC card system
Authors: Akio Shiibashi
Venue: Systems and Computers in Japan (2007)

Increasing the processing speed of automatic fare collection gates (AFCG) is a topic of great importance for supporting passengers who are getting on and off high-density transportation at peak hours. On the other hand, reliability is indispensable for processing tickets, which are a type of noncurrency negotiable instrument. Therefore, a passenger ticket system that provides both high-speed processing and high reliability is required. To increase passenger convenience and reduce maintenance costs, a wireless IC card ticket system is desirable. However, since this system uses wireless communication for processing that is carried out with the fare collection gates, the drop in data during ticket examination is a problem. In this paper, the author proposes an autonomous decentralized technology for satisfying the requirements of high-speed processing and high reliability in a wireless IC card ticket system. IC cards, automatic fare collection gates, and a central server are designed as nodes of an autonomous decentralized system. In particular, to achieve high-speed processing, the author proposes an autonomous decentralized algorithm for fare calculation by IC cards and automatic fare collection gates. To prove the effectiveness of this algorithm, the author creates models and performs comparison tests. Also, as a technology for ensuring high reliability, the author proposes an autonomous decentralized data consistency technology for each subsystem. These technologies were introduced in the Suica system (East Japan Railway Company) in Japan and their effectiveness was proven. &copy; 2007 Wiley Periodicals, Inc. Syst Comp Jpn, 38(9): 1&ndash;10, 2007; Published online in Wiley InterScience (). DOI 10.1002&sol;scj.20800
An On-line Algorithm for Fair-Share Node Allocations in a Cluster
Authors: Lior Amar, Amnon Barak, Ely Levy, Michael Okun
Venue: Proceedings of the Seventh IEEE International Symposium on Cluster Computing and the Grid (2007)

Proportional (fair) share schedulers are designed to provide applications with predefined portions of system resources. Single node operating systems use context-switch (preemption) to dynamically allocate the CPU(s) to running processes. This paper presents an on-line algorithm for proportional share allocations of nodes in a cluster, in a fashion that resembles a single-node system. The algorithm relies on preemptive process migrations for dynamic allocations of nodes to users. The paper presents the algorithm and its performance on a MOSIX organizational Grid with 60 nodes. We show that proportional share allocations can be achieved in a relatively short time (minutes).
Mechanisms for store-wait-free multiprocessors
Authors: Thomas F. Wenisch, Anastasia Ailamaki, Babak Falsafi, Andreas Moshovos
Venue: ACM SIGARCH Computer Architecture News (2007)

Store misses cause significant delays in shared-memory multiprocessors because of limited store buffering and ordering constraints required for proper synchronization. Today, programmers must choose from a spectrum of memory consistency models that reduce store stalls at the cost of increased programming complexity. Prior research suggests that the performance gap among consistency models can be closed through speculation--enforcing order only when dynamically necessary. Unfortunately, past designs either provide insufficient buffering, replace all stores with read-modify-write operations, and/or recover from ordering violations via impractical fine-grained rollback mechanisms. We propose two mechanisms that, together, enable store-wait-free implementations of any memory consistency model. To eliminate buffer-capacity-related stalls, we propose the scalable store buffer, which places private/speculative values directly into the L1 cache, thereby eliminating the non-scalable associative search of conventional store buffers. To eliminate ordering-related stalls, we propose atomic sequence ordering, which enforces ordering constraints over coarse-grain access sequences while relaxing order among individual accesses. Using cycle-accurate full-system simulation of scientific and commercial applications, we demonstrate that these mechanisms allow the simplified programming of strict ordering while outperforming conventional implementations on average by 32% (sequential consistency), 22% (SPARC total store order) and 9% (SPARC relaxed memory order).
Operation scheduling for parallel functional units using genetic algorithms
Authors: T. Zeitlhofer
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 1999. on 1999 IEEE International Conference - Volume 04 (1999)

We describe a new and efficient approach to solve the scheduling problem for VLIW architectures. The scheduling times of the operations are used as the problems parameters. This in conjunction with a pruning technique based on critical path analysis leads to a significant reduction of search space complexity. A genetic algorithm is used to search for valid schedules of a given length. The genetic algorithm uses a fitness vector that guides the genetic operators crossover and mutation resulting in a fast convergence towards near perfect solutions. The proposed method is also applicable to the problem of register allocation by using a different fitness function. Another advantage of the genetic algorithm approach is that usually a great number of equally performing schedules is obtained allowing for further optimization subject to arbitrary constraints.
Distributed Data Storage with Strong Offline Access Support
Authors: Lukas Hejtmanek, Ludek Matyska
Venue: Proceedings of the International Multi-Conference on Computing in the Global Information Technology (2007)

In this paper, we propose a distributed data storage framework that supports unrestricted offline access. The system does not explicitly distinguish between connected and disconnected states. Its design is based on a lock-free distributed framework that avoids update conflicts through file versioning. The feasibility of this framework is confirmed by a proof-of-concept implementation. We also demonstrate that the proposed lock-free replica synchronization algorithm scales well. A future work will include also direct support for non-versioned files.
DERRIC: A Tool for Unified Logic Diagnosis
Authors: A. Rousset, A. Bosio, P. Girard, C. Landrault, S. Pravossoudovitch, A. Virazel
Venue: Proceedings of the 12th IEEE European Test Symposium (2007)

This paper presents DERRIC (Diagnosis of logic ERRors in VLSI Integrated Circuits), a diagnostic tool targeting most of the fault models used in practice today. This tool is intended to be used to diagnose faulty behaviors in nanometric circuits for which the classical stuck-at fault model is far to cover all the realistic failures. The underlying method of DERRIC is based on the Effect-Cause approach which relies on the two following main operations. The first one is based on critical path tracing (CPT) that consists in identifying critical lines in the Circuit Under Test (CUT) which can be the source of observed errors. The second one consists in allocating a set of possible fault models to each critical line, so that root causes of failures can be finally determined. The main advantage of this method is that it does not need to explicitly consider each fault model during the diagnosis process. Experiments on ISCAS'85 and ITC'99 benchmarks show the efficiency of the proposed tool in terms of diagnosis resolution.
Analysis of Payload Based Application level Network Anomaly Detection
Authors: Like Zhang, Gregory B. White
Venue: Proceedings of the 40th Annual Hawaii International Conference on System Sciences (2007)

Most network anomaly detection research is based on packet header fields, while the payload is usually discarded. Preventing unknown attacks and Internet worms has led to a need for application level network anomaly detection. Payload based detection schemes in experiments are often misleading. In this paper, we discuss the problems associated with the experimental results. In the first section, a brief review will be given for application level anomaly detection research. Introduction to several major payload based approaches will be given in section 2. Then we use the DARPA'99 dataset to evaluate the ALAD mechanism, and discuss the problems by using original DARPA'99 datasets for evaluation. In the fourth section, an improved method will be proposed with a focus on detecting payload related attacks. In section 5, we demonstrate how to justify the payload based detection mechanism using the DARPA'99 dataset, and compare with ALAD to demonstrate its advantages.