ppxscal/embedding_network huggingface dataset:
Extracting Behavioral Data from Physical Descriptions of MEMS for Simulation
Authors: Dennis Gibson, Carla Purdy
Venue: Journal of VLSI Signal Processing Systems (1999)

The work described here deals with the problems of modeling and simulation for MEMS devices. The eventual goal is to produce a top-down MEMS design system similar to today&lsquo;s powerful VLSI design systems. In this work a fixed fabrication process (MUMPS) and a fixed layout tool (L-Edit) are chosen. Thus our efforts are concentrated on reliable simulation of designs and eventual comparison with actual fabricated parts. The cantilever beam is chosen as an example of how extraction from a physical layout may be modeled and interfaced with various simulators.
Mining frequent patterns without candidate generation
Authors: Jiawei Han, Jian Pei, Yiwen Yin
Venue: ACM SIGMOD Record (2000)

Mining frequent patterns in transaction databases, time-series databases, and many other kinds of databases has been studied popularly in data mining research. Most of the previous studies adopt an Apriori-like candidate set generation-and-test approach. However, candidate set generation is still costly, especially when there exist prolific patterns and/or long patterns. In this study, we propose a novel frequent pattern tree (FP-tree) structure, which is an extended prefix-tree structure for storing compressed, crucial information about frequent patterns, and develop an efficient FP-tree-based mining method, FP-growth, for mining the complete set of frequent patterns by pattern fragment growth. Efficiency of mining is achieved with three techniques: (1) a large database is compressed into a highly condensed, much smaller data structure, which avoids costly, repeated database scans, (2) our FP-tree-based mining adopts a pattern fragment growth method to avoid the costly generation of a large number of candidate sets, and (3) a partitioning-based, divide-and-conquer method is used to decompose the mining task into a set of smaller tasks for mining confined patterns in conditional databases, which dramatically reduces the search space. Our performance study shows that the FP-growth method is efficient and scalable for mining both long and short frequent patterns, and is about an order of magnitude faster than the Apriori algorithm and also faster than some recently reported new frequent pattern mining methods.
Power minimization using system-level partitioning of applications with quality of service requirements
Authors: Gang Qu, Miodrag Potkonjak
Venue: Proceedings of the 1999 IEEE/ACM international conference on Computer-aided design (1999)

Design systems to provide various quality of service (QoS) guarantees has received a lot of attentions due to the increasing popularity of real-time multimedia and wireless communication applications. Meanwhile, low power consumption is always one of the goals for system design, especially for battery-operated systems. With the design trend of integrating multiple processor cores and memory on a single chip, we address the problem of how to partition a set of applications among processors, such that all the individual QoS requirements are met and the total energy consumption is minimized. We exploit the advantages provided by the variable voltage design methodology to choose the voltage for each application on the same processor optimally for this purpose. We also discuss how to partition applications among the processors to achieve the same goal. We formulate the problem on an abstract QoS model and present how to allocate resources (e.g., CPU time) and determine the voltage profile for every single processor. Experiments on media benchmarks have also been studied.
Improving TCP performance over wireless networks at the link layer
Authors: Christina Parsa, J. J. Garcia-Luna-Aceves
Venue: Mobile Networks and Applications (2000)

We present the transport unaware link improvement protocol (TULIP), which dramatically improves the performance of TCP over lossy wireless links, without competing with or modifying the transport- or network-layer protocols. TULIP is tailored for the half-duplex radio links available with today's commercial radios and provides a MAC acceleration feature applicable to collision-avoidance MAC protocols (e.g., IEEE 802.11) to improve throughput. TULIP's timers rely on a maximum propagation delay over the link, rather than performing a round-trip time estimate of the channel delay. The protocol does not require a base station and keeps no TCP state. TULIP is exceptionally robust when bit error rates are high; it maintains high goodput, i.e., only those packets which are in fact dropped on the wireless link are retransmitted and then only when necessary. The performance of TULIP is compared against the performance of the Snoop protocol (a TCP-aware approach) and TCP without link-level retransmission support. The results of simulation experiments using the actual code of the Snoop protocol show that TULIP achieves higher throughput, lower packet delay, and smaller delay variance.
Automatic Segmentation of Acoustic Musical Signals Using Hidden Markov Models
Authors: Christopher Raphael
Venue: IEEE Transactions on Pattern Analysis and Machine Intelligence (1999)

In this paper, we address an important step toward our goal of automatic musical accompaniment¿the segmentation problem. Given a score to a piece of monophonic music and a sampled recording of a performance of that score, we attempt to segment the data into a sequence of contiguous regions corresponding to the notes and rests in the score. Within the framework of a hidden Markov model, we model our prior knowledge, perform unsupervised learning of the data model parameters, and compute the segmentation that globally minimizes the posterior expected number of segmentation errors. We also show how to produce "on-line" estimates of score position. We present examples of our experimental results, and readers are encouraged to access actual sound data we have made available from these experiments.
Plenoptic sampling
Authors: Jin-Xiang Chai, Xin Tong, Shing-Chow Chan, Heung-Yeung Shum
Venue: Proceedings of the 27th annual conference on Computer graphics and interactive techniques (2000)

This paper studies the problem of plenoptic sampling in image-based rendering (IBR). From a spectral analysis of light field signals and using the sampling theorem, we mathematically derive the analytical functions to determine the minimum sampling rate for light field rendering. The spectral support of a light field signal is bounded by the minimum and maximum depths only, no matter how complicated the spectral support might be because of depth variations in the scene. The minimum sampling rate for light field rendering is obtained by compacting the replicas of the spectral support of the sampled light field within the smallest interval. Given the minimum and maximum depths, a reconstruction filter with an optimal and constant depth can be designed to achieve anti-aliased light field rendering. Plenoptic sampling goes beyond the minimum number of images needed for anti-aliased light field rendering. More significantly, it utilizes the scene depth information to determine the minimum sampling curve in the joint image and geometry space. The minimum sampling curve quantitatively describes the relationship among three key elements in IBR systems: scene complexity (geometrical and textural information), the number of image samples, and the output resolution. Therefore, plenoptic sampling bridges the gap between image-based rendering and traditional geometry-based rendering. Experimental results demonstrate the effectiveness of our approach.
Classroom Note: Centrosymmetric Matrices
Authors: Alan L. Andrew
Venue: SIAM Review (1998)

Attention is drawn to some earlier work on the odd--even properties of eigenvectors of centrosymmetric matrices.
E-commerce organizational structure (extended abstract): an integration of four cases
Authors: Rebecca Grant
Venue: Proceedings of the 2000 ACM SIGCPR conference on Computer personnel research (2000)

In expanding into e-commerce, clicks and mortar companies have many options. They can outsource all of the e-commerce related activities to firms specializing in those tasks. They can bring in new employees with the required skills &mdash; either integrating them into work units with current employees or setting up new e-commerce units. They can retrain or redirect existing employees. Or they can combine these approaches. This paper reports on the first phase of a three-phase project that studies how contemporary businesses structure their IS areas to take advantage of the Internet and the World Wide Web. The research studies established businesses in order to understand how they implement their business-to-business e-commerce. A preliminary set of interviews looked at four firms (all company names have been disguised) in Canada and the United States that actively conduct business-to-business e-commerce and that had well-established IS groups prior to the move to e-commerce. The first firm, Technology and Software (T/S), was a Canadian plant automation design firm that employs 400 individuals, 40 of them in IS. Its first e-commerce application involved a Y2K compliance database which began as a client-defined project and evolved into a commercial product. The second company examined was Commercial Insurers (C/I), an international commercial and personal insurance company based in the U.S. With 9500 employees worldwide (approximately 1000 in IS), the company conducts web-based business with its independent agents and brokers at multiple levels. U.S. Office Supplier (UOS) is a major office products supplier with 12,000 employees and an IS group of 270. Its e-commerce systems provide online ordering, catalogue searching, and order tracking for its customers. The fourth company studied was Canadian Office Supplier (COS), a wholly-owned subsidiary of U.S. Office Supplier. With 2,100 employees (50 in IS), the company's systems are similar to those of its parent but were developed independently and, in some cases, first. Each of the firms used a different organization structure to develop and build its e-commerce systems. T/S began with an internal project team, but ultimately moved to a product team staffed from existing IS personnel. C/I created a business applications group drawn from outside the IS group (responsible for developing applications) and an internal technical group for the technical infrastructure needed to deliver e-commerce. UOS, which hired new IS staff and contract programmers, created a new e-commerce unit reporting to the marketing area. COS, on the other hand, used a team of COS managers for ideas and oversight, but outsourced all programming and implementation. This paper proposes a model for future research that distinguishes the structural options according to two dimensions. It goes on to describe the possible normative and predictive uses of the model, as well as the mechanisms for validating those uses.
Improving problem-oriented mailing list archives with MCS
Authors: Robert S. Brewer
Venue: Proceedings of the 22nd international conference on Software engineering (2000)

Developers often use electronic mailing lists when seeking assistance with a particular software application. The archives of these mailing lists provide a rich repository of problem-solving knowledge. Developers seeking a quick answer to a problem find these archives inconvenient, because they lack efficient searching mechanisms, and retain the structure of the original conversational threads which are rarely relevant to the knowledge seeker.We present a system called MCS which improves mailing list archives through a process called condensation. Condensation involves several tasks: extracting only messages of longer-term relevance, adding metadata to those messages to improve searching, and potentially editing the content of the messages when appropriate to clarify. The condensation process is performed by a human editor (assisted by a tool), rather than by an artificial intelligence (AI) system.We describe the design and implementation of MCS, and compare it to rlated systems. We also present our experiences condensing a 1428 message mailing list archive to an archive containing only 177 messages (an 88% reduction). The condensation required only 1.5 minutes of editor effort per message. The condensed archive was adopted by the users of the mailing list.
A New Current-Mode Synthesis Method for Dynamic Translinear Filters and its Applications in Hearing Instruments
Authors: D. Masmoudi, W. A. Serdijn, J. Mulder, A. C. Van Der Woerd, J. Tomas, J. P. Dom
Venue: Analog Integrated Circuits and Signal Processing (2000)

A new current mode synthesis method for dynamic translinear filters is proposed. As a design example, we have considered an ultra-low power second order filter working in audio frequency range, for hearing aids application, and using subthreshold MOS devices. It has a nominal supply voltage of 1.2 V and works down to 1 Volt. It has a power consumption of 5 &mu;W. The filter cut-off frequency and its Q factor can be tuned respectively from 600 Hz to 13 kHz and from 0.6 to 1.1. Mismatch problems are investigated on the circuit level and an on-chip compensation method is proposed.
Fast Estimation of Diameter and Shortest Paths (Without Matrix Multiplication)
Authors: D. Aingworth, C. Chekuri, P. Indyk, R. Motwani
Venue: SIAM Journal on Computing (1999)

In the recent past, there has been considerable progress in devising algorithms for the all-pairs shortest paths (APSP) problem running in time significantly smaller than the obvious time bound of O(n3). Unfortunately, all the new algorithms are based on fast matrix multiplication algorithms that are notoriously impractical. Our work is motivated by the goal of devising purely combinatorial algorithms that match these improved running times. Our results come close to achieving this goal, in that we present algorithms with a small additive error in the length of the paths obtained. Our algorithms are easy to implement, have the desired property of being combinatorial in nature, and the hidden constants in the running time bound are fairly small.Our main result is an algorithm which solves the APSP problem in unweighted, undirected graphs with an additive error of 2 in time $O(n^{2.5}\sqrt{\log n})$. This algorithm returns actual paths and not just the distances. In addition, we give more efficient algorithms with running time {\footnotesize $O(n^{1.5} \sqrt{k \log n} + n^2 \log^2 n)$} for the case where we are only required to determine shortest paths between k specified pairs of vertices rather than all pairs of vertices. The starting point for all our results is an $O(m \sqrt{n \log n})$ algorithm for distinguishing between graphs of diameter 2 and 4, and this is later extended to obtaining a ratio 2/3 approximation to the diameter in time $O(m \sqrt{n \log n} + n^2 \log n)$. Unlike in the case of APSP, our results for approximate diameter computation can be extended to the case of directed graphs with arbitrary positive real weights on the edges.
Software engineering programmes are not computer science programmes
Authors: David Lorge Parnas
Venue: Annals of Software Engineering (1999)

Programmes in &ldquo;Software Engineering&rdquo; have become a source of contention in many universities. Some Computer Science departments, many of which have used that phrase to describe individual courses for decades, claim software engineering as part of their discipline. However, Engineering faculties claim &ldquo;Software Engineering&rdquo; as a new speciality in the family of engineering disciplines. This paper discusses the differences between traditional computer science programmes and most engineering programmes and argues that we need programmes that follow the traditional engineering approach to professional education and educate engineers whose speciality within engineering is software construction. One such programme is described.
JMTP: an architecture for exploiting concurrency in embedded Java applications with real-time considerations
Authors: Rachid Helaihel, Kunle Olukotun
Venue: Proceedings of the 1999 IEEE/ACM international conference on Computer-aided design (1999)

Using Java in embedded systems is plagued by problems of limited runtime performance and unpredictable runtime behavior. The Java Multi-Threaded Processor (JMTP) provides solutions to these problems. The JMTP architecture is a single chip containing an off-the-shelf general purpose processor core coupled with an array of Java Thread Processors (JTPs). Performance can be improved using this architecture by exploiting coarse-grained parallelism in the application. These performance improvements are achieved with relatively small hardware costs. Runtime predictability is improved by implementing a subset of the Java Virtual Machine (JVM) specification in the JTP and trimming away complexity without excessively restricting the Java code a JTP can handle. Moreover, the JMTP architecture incorporates hardware to adaptively manage shared JMTP resources in order to satisfy JTP thread timing constraints or provide an early warning for a timing violation. This is an important feature for applications with quality-of-service demands. In addition to the hardware architecture, we describe a software framework that analyzes a Java application for expressed and implicit coarse-grained concurrent threads to execute on JTPs. This framework identifies the optimal mapping of an application to a JMTP with an arbitrary number of JTPs. We have tested this framework on a variety of applications including IDEA encryption with different JTP configurations and confirmed that the algorithm was able to obtain desired results in each case.
Lagrange Inversion and Schur Functions
Authors: Cristian Lenart
Venue: Journal of Algebraic Combinatorics: An International Journal (2000)

Macdonald defined an involution on symmetric functions by considering the Lagrange inverse of the generating function of the complete homogeneous symmetric functions. The main result we prove in this note is that the images of skew Schur functions under this involution are either Schur positive or Schur negative symmetric functions. The proof relies on the combinatorics of Lagrange inversion. We also present a q-analogue of this result, which is related to the q-Lagrange inversion formula of Andrews, Garsia, and Gessel, as well as the operator &nabla; of Bergeron and Garsia.
Time-Frequency Analysis Using Local Taylor Series Expansion
Authors: Erik Friedlander
Venue: Multidimensional Systems and Signal Processing (1998)

We describe an approach to time-frequency analysis based on the local approximation of the signal by a first order Taylor series. We show that the Taylor approximation provides a representation of the signal in terms of its instantaneous frequency and instantaneous bandwidth. This representation can be translated into the frequency domain in a straightforward manner. The key to this approach is the local decomposition of the signal into its components, which is similar to the problem of estimating the parameters of of complex exponentials from observation of their sum. The resulting time-frequency representation (TFR) does not have the time and frequency marginal properties shared by many of the time-frequency distributions presented in the literature, but is additive over the signal components and, by its construction, does not have cross-terms.
A scalable approach to thread-level speculation
Authors: J. Greggory Steffan, Christopher B. Colohan, Antonia Zhai, Todd C. Mowry
Venue: ACM SIGARCH Computer Architecture News (2000)

While architects understand how to build cost-effective parallel machines across a wide spectrum of machine sizes (ranging from within a single chip to large-scale servers), the real challenge is how to easily create parallel software to effectively exploit all of this raw performance potential. One promising technique for overcoming this problem is Thread-Level Speculation (TLS), which enables the compiler to optimistically create parallel threads despite uncertainty as to whether those threads are actually independent. In this paper, we propose and evaluate a design for supporting TLS that seamlessly scales to any machine size because it is a straightforward extension of writeback invalidation-based cache coherence (which itself scales both up and down). Our experimental results demonstrate that our scheme performs well on both single-chip multiprocessors and on larger-scale machines where communication latencies are twenty times larger.
An efficient self-simulation algorithm for reconfigurable meshes
Authors: Susumu Matsumae, Nobuki Tokura
Venue: Proceedings of the twelfth annual ACM symposium on Parallel algorithms and architectures (2000)

A reconfigurable mesh (RM) is the two-dimensional mesh-connected computer enhanced with a reconfigurable bus system. The bus system is used to dynamically obtain various interconnection patterns among the processors during the execution of programs. This paper shows that the RM of size n &times; n can be simulated in O(n2/m2 log n) steps by the RM of smaller size m &times; m (m < n). The algorithm improves the previously known best results, O (n2/m2 log m log n / m) steps proposed by Fern&aacute;ndez-Zepeda et al., under some conditions (e.g. m = nc for a constant c with 0 < c < 1). Furthermore, our simulation algorithm can run on the restricted model of the RM called linear RM, which is a simpler model than that used by Fern&aacute;ndez-Zepeda et al.
The incremental deployability of RTT-based congestion avoidance for high speed TCP Internet connections
Authors: Jim Martin, Arne Nilsson, Injong Rhee
Venue: ACM SIGMETRICS Performance Evaluation Review (2000)

Our research focuses on end-to-end congestion avoidance algorithms that use round trip time (RTT) fluctuations as an indicator of the level of network congestion. The algorithms are referred to as delay-based congestion avoidance or DCA. Due to the economics associated with deploying change within an existing network, we are interested in an incrementally deployable enhancement to the TCP/Reno protocol. For instance, TCP/Vegas, a DCA algorithm, has been proposed as an incremental enhancement. Requiring relatively minor modifications to a TCP sender, TCP/Vegas has been shown to increase end-to-end TCP throughput primarily by avoiding packet loss. We study DCA in today's best effort Internet where IP switches are subject to thousands of TCP flows resulting in congestion with time scales that span orders of magnitude. Our results suggest that RTT-based congestion avoidance may not be reliably incrementally deployed in this environment. Through extensive measurement and simulation, we find that when TCP/DCA (i.e., a TCP/Reno sender that is extended with DCA) is deployed over a high speed Internet path, the flow generally experiences degraded throughput compared to an unmodified TCP/Reno flow. We show (1) that the congestion information contained in RTT samples is not sufficient to predict packet loss reliably and (2) that the congestion avoidance in response to delay increase has minimal impact on the congestion level over the path when the total DCA traffic at the bottleneck consumes less than 10% of the bottleneck bandwidth.