ppxscal/embedding_network huggingface dataset:
Experimental and computational analysis of random cylinder packings with applications
Authors: Karsten E. Thompson
Venue:  (2006)

Random cylinder packings are prevalent in chemical engineering applications and they can serve as prototype models of fibrous materials and/or other particulate materials. In this research, comprehensive studies on cylinder packings were carried out by computer simulations and by experiments. The computational studies made use of a collective rearrangement algorithm (based on a Monte Carlo technique) to generate different packing structures. 3D random packing limits were explored, and the packing structures were quantified by their positional ordering, orientational ordering, and the particle-particle contacts. Furthermore, the void space in the packings was expressed as a pore network, which retains topological and geometrical information. The significance of this approach is that any irregular continuous porous space can be approximated as a mathematically tractable pore network, thus allowing for efficient microscale flow simulation. Single-phase flow simulations were conducted, and the results were validated by calculating permeabilities. In the experimental part of the research, a series of densification experiments were conducted on equilateral cylinders. X-ray microtomography was used to image the cylinder packs, and the particle-scale packings were reconstructed from the digital data. This numerical approach makes it possible to study detailed packing structure, packing density, the onset of ordering, and wall effects. Orthogonal ordering and layered structures were found to exist at least two characteristic diameters from the wall in cylinder packings. Important applications for cylinder packings include multiphase flow in catalytic beds, heat transfer, bulk storage and transportation, and manufacturing of fibrous composites.
Mean-Variance Portfolio Selection under Partial Information
Authors: Jie Xiong, Xun Yu Zhou
Venue: SIAM Journal on Control and Optimization (2007)

This paper is concerned with a continuous-time mean-variance portfolio selection problem in a (possibly incomplete) market with multiple stocks and a bond. Only the past price movements of the stocks and the bond are the information available to the investors. A separation principle is shown to hold in this setting. Efficient strategies based on the aforementioned partial information are derived, which involve the optimal filter of the stock appreciation rate processes. The main methodological contribution of the paper is to employ the particle system representation to develop analytical and numerical approaches in obtaining the filter as well as solving the related backward stochastic differential equation.
BIT: a tool for instrumenting java bytecodes
Authors: Han Bok Lee, Benjamin G. Zorn
Venue: Proceedings of the USENIX Symposium on Internet Technologies and Systems on USENIX Symposium on Internet Technologies and Systems (1997)

BIT (Bytecode Instrumenting Tool) is a collection of Java classes that allow one to build customized tools to instrument Java Virtual Machine (JVM) bytecodes. Because understanding program behavior is an essential part of developing effective optimization algorithms, researchers and software developers have built numerous tools that carry out program analysis. Although there are existing tools that analyze and modify executables on a variety of operating systems and machine architectures, there currently is no framework for carrying out the same task for JVM bytecodes. In this paper, we describe BIT, which allows the user to insert calls to analysis methods anywhere in the bytecode, so that information can be extracted from the user program while it is being executed. In this paper, we describe several simple tools built using BIT and also report on BIT's performance. We found that the overhead for the execution speed and size were between 23% to 150%.
Iterative algorithms for a new system of nonlinear variational inclusions with (A,η)-accretive mappings in Banach spaces
Authors: Mao-Ming Jin
Venue: Computers Mathematics with Applications (2007)

In this paper we introduce and study a new system of nonlinear variational inclusions with (A,@h)-accretive mappings in Banach spaces. By using the resolvent operator associated with (A,@h)-accretive mappings, we construct some new iterative algorithms for approximating the solution of this system of variational inclusions. We also prove the existence of solutions and the convergence of the sequences generated by the algorithm in Banach spaces. The results presented in this paper extend and improve some known results in the literature.
Exploiting the capture effect for collision detection and recovery
Authors: K. Whitehouse, A. Woo, F. Jiang, J. Polastre, D. Culler
Venue: Proceedings of the 2nd IEEE workshop on Embedded Networked Sensors (2005)

In this paper we evaluate a technique to detect and recover messages from packet collisions by exploiting the capture effect. It can differentiate between collisions and packet loss and can identify the nodes involved in the collisions. This information is provided at virtually no extra cost and can produce significant improvements in existing collision mediation schemes. We characterize this technique using controlled collision experiments and evaluate it in real world flooding experiments on a 36-node sensor network.
A Formal Model for Integrating Multiple Views
Authors: J. K. F. Bowles, B. Bordbar
Venue: Proceedings of the Seventh International Conference on Application of Concurrency to System Design (2007)

In this paper we show how to use labelled event structures as a unique mathematical representation for design models consisting of different UML 2.0 diagrams/notation. Each diagram is used to capture a particular aspect or view of the system including structural and behavioural aspects. Our approach enables the analysis of complex systems designed in a combination of UML 2.0 notation, and serves as a means to detect inconsistencies in design.
User Perception and Preference in Model Mediated Telemanipulation
Authors: Probal Mitra, Diana Gentry, Gunter Niemeyer
Venue: Proceedings of the Second Joint EuroHaptics Conference and Symposium on Haptic Interfaces for Virtual Environment and Teleoperator Systems (2007)

Model mediated teleoperation allows users to interact with a remote environment via a local rendition to mitigate the effects of large communication delays. As the slave encounters an environment a model is identified, transmitted to the master, then haptically and graphically recreated. Particular attention must be paid to the user interface when model information is updated, to avoid confusion or disruptive effects. This paper examines various transition methods from the perspective of user preferences and perception. Transitions are grouped according to three basic philosophies: hiding changes from the user, forcing changes upon the user, and alerting users to model updates. A user study is presented which evaluated subjects' performance and opinions for different approaches. We found transitions that gradually but actively presented information to be the most successful.
Interactive presentation: Automatic generation of functional coverage models from behavioral verilog descriptions
Authors: Shireesh Verma, Ian G. Harris, Kiran Ramineni
Venue: Proceedings of the conference on Design, automation and test in Europe (2007)

As an industrial practice, the functional coverage models are developed based on a high-level specification of the Design Under Verification (DUV). However, in the course of implementation a designer makes specific choices which may not be reflected well in a functional coverage model developed entirely from a high-level specification. We present a method to automatically generate implementation-aware coverage models based on the static analysis of a HDL description of the DUV. Experimental results show that the functional coverage models generated using our technique correlate well with the detection of randomly injected errors into a design.
A design project based approach to teaching automatic control theory to mechanical engineers
Authors: J. L. Newcomer
Venue: Proceedings of the 28th Annual Frontiers in Education - Volume 03 (1998)

Most Mechanical Engineering Programs have an automatic controls course as a required class for juniors or seniors, and most face similar problems. Many students view the class as a large collection of abstract mathematics, and even if they come to enjoy the material and understand how to do the problems, few students walk away from the class feeling confident that they understand how to apply the material to real systems. The most common methods used to alleviate this situation are laboratories and design projects. The author describes how, in Spring 1997, at the University of Wisconsin (USA), he tried a new approach, teaching automatic controls in the same manner he would teach a course centered around design projects. Rather than using a single design project and handing it out in the middle of the semester, he assigned four design projects and handed them out the first day of class. His intention was to provide students with a breadth of design experiences, and also to pet them to think about the design of controllers as an ongoing process for which the theory provides a set of analysis tools. The results were very positive. Students appeared to come away with a better grasp of the material, had more confidence that they could apply the material outside of the classroom and liked the class better than previous groups of students had, despite a significantly increased workload over past semesters. 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
A scalable signature scheme for video authentication
Authors: Pradeep K. Atrey, Wei-Qi Yan, Mohan S. Kankanhalli
Venue: Multimedia Tools and Applications (2007)

This paper addresses the problem of ensuring the integrity of a digital video and presents a scalable signature scheme for video authentication based on cryptographic secret sharing. The proposed method detects spatial cropping and temporal jittering in a video, yet is robust against frame dropping in the streaming video scenario. In our scheme, the authentication signature is compact and independent of the size of the video. Given a video, we identify the key frames based on differential energy between the frames. Considering video frames as shares, we compute the corresponding secret at three hierarchical levels. The master secret is used as digital signature to authenticate the video. The proposed signature scheme is scalable to three hierarchical levels of signature computation based on the needs of different scenarios. We provide extensive experimental results to show the utility of our technique in three different scenarios--streaming video, video identification and face tampering.
A Socio-cognitive Approach to Modeling Policies in Open Environments
Authors: Tatyana Ryutov
Venue: Proceedings of the Eighth IEEE International Workshop on Policies for Distributed Systems and Networks (2007)

The richness of today's electronic communications mirrors physical world: activities such as shopping, business and scientific collaboration are conducted online. Current interactions have become a form of social exchange where participants must deal with complexity, uncertainty and risk. We propose a policy specification approach that combines social sciences and trust theory to facilitate ad-hoc interactions of self-interested parties in open environments. Our socio-cognitive approach allows us to reason about uncertainty and risk involved in a transaction, and automatically calculate the minimum trust threshold needed to mitigate the vulnerabilities. The trust threshold comprises the core of security policies that govern the interactions. The threshold calculation is based on balancing objective and subjective trust components, which together predict that a transaction will result in an acceptable outcome. We propose to apply the Prospect Theory [20] to specify policies that determine a set of acceptable outcomes. We present the trust threshold negotiation primitives.
An adaptive matched filter detector for distributed targets in homogeneous environment
Authors: E. Conte
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 01 (2000)

An adaptive detector of range-spread targets embedded in Gaussian noise with unknown covariance matrix is developed and assessed. The proposed receiver requires no prior knowledge about the target strength and its scattering geometry and achieves constant false alarm rate with respect to the noise covariance matrix.
Octave and Python: High-Level Scripting Languages Productivity and Performance Evaluation
Authors: Juan Carlos Chaves, John Nehrbass, Brian Guilfoos, Judy Gardiner, Stanley Ahalt, Ashok Krishnamurthy, Jose Unpingco, Alan Chalker, Andy Warnock, Siddharth Samsi
Venue: Proceedings of the HPCMP Users Group Conference (2006)

Octave and Python are open source alternatives to MATLAB, which is widely used by the High Performance Computing Modernization Program (HPCMP) community. These languages are two well known examples of high-level scripting languages that promise to increase productivity without compromising performance on HPC systems. In this paper, we report our work and experience with these two non-traditional programming languages at the HPCMP Centers. We used a representative sample of SIP codes for the study, with special emphasis given to the understanding of issues such as portability, degree of complexity, productivity and suitability of Octave and Python to address Signal/Image Processing (SIP) problems on the HPCMP HPC platforms.
A decision network framework for the behavioral animation of virtual humans
Authors: Qinxin Yu, Demetri Terzopoulos
Venue: Proceedings of the 2007 ACM SIGGRAPH/Eurographics symposium on Computer animation (2007)

We introduce a framework for advanced behavioral animation in virtual humans, which addresses the challenging open problem of simulating social interactions between pedestrians in urban settings. Based on hierarchical decision networks, our novel framework combines probability, decision, and graph theories for complex behavior modeling and intelligent action selection subject to manifold internal and external factors in the presence of uncertain knowledge. It yields autonomous characters that can make nontrivial interpretations and arrive at rational decisions dependent on multiple considerations. We demonstrate our framework in behavioral animation scenarios involving interacting autonomous pedestrians, including an elaborate emergency response animation.
Lockmeter: highly-informative instrumentation for spin locks in the linux® kernel
Authors: Ray Bryant, John Hawkes
Venue: Proceedings of the 4th annual Linux Showcase & Conference - Volume 4 (2000)

Lockmeter is a tool for instrumenting the spin locks in a multiprocessor Linux kernel. Lockmeter was designed to make minimal cache disruptions, taking care to both minimize cache misses and also to minimize interprocessor cache coherency operations. Lockmeter is "highly informative" in the sense that not only does it record overall statistics for each spin lock, it also reports (where possible) these statistics on a per caller basis. This allows one to readily identify which portions of the kernel code are responsible for causing lock contention. In this paper, we describe the capabilities and implementation of Lockmeter version 1.3.
A novel criticality computation method in statistical timing analysis
Authors: Feng Wang, Yuan Xie, Hai Ju
Venue: Proceedings of the conference on Design, automation and test in Europe (2007)

The impact of process variations increases as technology scales to nanometer region. Under large process variations, the path and arc/node criticality [18] provide effective metrics in guiding circuit optimization. To facilitate the criticality computation considering the correlation, we define the critical region for the path and arc/node in a timing graph, and propose an efficient method to compute the criticality for paths and arcs/nodes simultaneously by a single breadth-first graph traversal during the backward propagation. Instead of choosing a set of paths for analysis prematurely, we develop a new property of the path criticality to prune those paths with low criticality at very earlier stages, so that our path criticality computation method has linear complexity with respect of the timing edges in a timing graph. To improve the computation accuracy, cutset and path criticality properties are exploited to calibrate the computation results. The experimental results on ISCAS benchmark circuits show that our criticality computation method can achieve high accuracy with fast speed.
Decision Tree Construction from Multidimensional Structured Data
Authors: Tomoki Watanuma, Tomonobu Ozaki, Takenao Ohkawa
Venue: Proceedings of the Sixth IEEE International Conference on Data Mining - Workshops (2006)

Since most structured data mining techniques specialize in mining from single structured data, it cannot handle more realistic data which consist of different and plural kinds of structured data. To cope with this problem, we propose an algorithm for constructing decision trees from multidimensional structured data by introducing the techniques for mining correlated and closed patterns with effective pruning capabilities into the traditional TDIDT approach. The results of the experiments with real world data show the effectiveness of the proposed algorithm.
Characterization of High Altitude Turbulence for Air Force Platforms
Authors: Frank H. Ruggiero, Joseph A. Werne, Alex Mahalov, Basil Nichols
Venue: Proceedings of the HPCMP Users Group Conference (2006)

The Air Force has a pressing and unique need to characterize and predict high-altitude (z > 10 km MSL) turbulence (HAT). Mechanical turbulence at these altitudes will impact surveillance and reconnaissance aircraft, both manned and unmanned. At a minimum the turbulence will degrade surveillance and reconnaissance operations by forcing the pilot or operator to focus on flying the aircraft instead of taking observations, and by causing jitter that degrades the effectiveness of the surveillance sensors. At worst, the turbulence can jeopardize the safety of the aircraft. Not the same as mechanical turbulence but related to it is optical turbulence. Optical turbulence is caused by gradients of the index of refraction that occur in areas of small scale temperature inhomogeneities, typically on the edges of regions of mechanical turbulence. Optical turbulence impacts laser propagation by reducing the power and focus of the beam and thus adversely impacts directed energy weapon and communication systems. While atmospheric turbulence near the earth's surface is fairly well understood, less is known about turbulence in the predominately stably-stratified free atmosphere.
Managing and Delivering Context-Dependent User Preferences in Ubiquitous Computing Environments
Authors: Michael Sutterer, Olivier Coutand, Olaf Droegehorn, Klaus David, Kees van der Sluijs
Venue: Proceedings of the 2007 International Symposium on Applications and the Internet Workshops (2007)

We present a user profile management component for ubiquitous computing environments that provides management, inquiry and delivery of context-dependent user preferences. In particular, our approach takes into account that users act differently depending on their current context, and hence, that a user can be described by different submodels that represent the user's preferences within different contexts. Furthermore, our approach takes into account that different applications usually adhere to different semantics.
Research and Design of Mobile Impeachment System with Semi-cryptonym
Authors: Chaobo Yang, Ming Qi
Venue: Proceedings of the The Second International Conference on Availability, Reliability and Security (2007)

The mobile impeachment system with semi-cryptonym which is designed in this paper for the first time slakes impeachment's disadvantages of both cryptonym and autonym, whose evidences are mainly audio frequency, photo and video with letters as assistant. The system solves the problems of impeachment through network effectively with simple operations, faster transmission speed and better security. It also talks about some problems during the process of execution at the end of this paper.
A request cluster allocation method for DOCSIS CATV/HFC networks
Authors: T. Saito, K. Kato, H. Inai
Venue: Proceedings of the The 8th International Conference on Communication Systems - Volume 01 (2002)

As an access medium to the Internet, CATV/HFC networks have been widespread recently. In such networks, each station reserves its data PDU transmission during a request period called a request cluster. DOCKS, a de facto standard for the networks, employs the binary back-off method for request cluster allocation. Since that method normally allocates unnecessary large request cluster, the transmission delay increases under heavy load conditions. We propose a request cluster allocation method which dynamically changes the cluster size according to the load conditions. In order to evaluate performance of the proposed method, we build a queuing model and execute computer simulation. The simulation result shows that the proposed method provides smaller delay than the binary back-off method.
Using Image Flow to Detect Eye Blinks in Color Videos
Authors: Ric Heishman, Zoran Duric
Venue: Proceedings of the Eighth IEEE Workshop on Applications of Computer Vision (2007)

Static computer vision techniques enable non-intrusive observation and analysis of biometrics such as eye blinks. However, ambiguous eye behaviors such as partial blinks and asymmetric eyelid movements present problems that computer vision techniques relying on static appearance alone cannot solve reliably. Image flow analysis enables reliable and efficient interpretation of these ambiguous eye blink behaviors. In this paper we present a method for using image flow analysis to compute problematic eye blink parameters. The flow analysis produces the magnitude and direction of the eyelid movement. A deterministic finite state machine uses the eyelid movement data to compute blink parameters (e.g., blink count, blink rate, and other transitional statistics) for use in human computer interaction applications across a wide range of disciplines. We conducted extensive experiments employing this method on approximately 750K color video frames of five subjects.
Bayesian estimation of a class of chaotic signals
Authors: C. Pantaleon
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 01 (2000)

Chaotic signals are potentially attractive in a wide range of signal processing applications. This paper deals with Bayesian estimation of chaotic sequences generated by tent maps and observed in white noise. The existence of invariant distributions associated with these sequences makes the development of Bayesian estimators quite natural. Both maximum a posteriori (MAP) and minimum mean square error (MMSE) estimators are derived. Computer simulations confirm the expected performance of both approaches and show how the inclusion of a priori information produces in most cases an increase in performance over the maximum likelihood (ML) case.