ppxscal/embedding_network huggingface dataset:
Chartindex: a contextual approach to automated standards-based encoding of clinical documents
Authors: Henry J. Lowe
Venue:  (2007)

Introduction. Structured and encoded clinical information is critical to implementing intelligent clinical applications and clinical research. However, large amounts of important clinical information are still in unstructured free-text clinical documents, difficult to retrieve and exchange, and need to be encoded into structured form. This dissertation presents new methods to improve automated encoding of narrative clinical documents using controlled terminologies, with a focus on improving encoding precision, and the corresponding findings.Methods. I implemented a scalable mechanism to reliably convert semi-structured clinical documents into a standard document model, the HL7 Clinical Document Architecture (CDA), with document sections properly represented according to their canonical types. I also carried out a pilot study on a contextual encoding method, which leveraged the information on document section types.As an approach to improving the encoding precision, I explored a new method of improving general-purpose medical text processing---parse each sentence using a high-performance statistical natural language parser augmented with a comprehensive biomedical lexicon.To further improve encoding precision, I devised a novel hybrid approach to detecting negations in clinical documents. This approach first classified a sentence according to a syntactical negation categorization using regular expression matching; then it located negated phrases in parse trees using a grammatical approach.Results. The pilot study on contextual indexing showed that significant improvements on indexing precision were achieved with limited negative impact on indexing recalls for most types of radiology reports and report sections. After augmenting the general-purpose statistical parser with a standard biomedical lexicon, the F-1 measure was improved from 86.7% to 92.8% for base noun phrases. The hybrid approach for negation detection achieved a sensitivity of 92.6% (95% CI 90.9-93.4%), a positive predictive value (PPV) of 98.6% (95% CI 96.9-99.4%) and a specificity of 99.8% (95% CI 99.7-99.9%). Conclusions. The standards-based contextual indexing approach, together with the new approach of medical text processing and the new method of negation detection have been shown to be promising in the improvement of indexing precisions. The structural information in sentence parse trees enables precise information extractions such as detecting negated biomedical terms.
Automatic text classification using a multi-agent framework
Authors: Javed Mostafa
Venue:  (2006)

Automatic text classification is an important operational problem in information systems. Most automatic text classification efforts so far concentrated on developing centralized solutions. However, centralized classification approaches often are limited due to constraints on knowledge and computing resources. To overcome the limitations of centralized approaches, an alternative distributed approach based on a multi-agent framework is proposed. Three major challenges associated with distributed text classification are examined: (1) Coordinating classification activities in a distributed environment, (2) Achieving high quality classification, and (3) Minimizing communication overhead. This study presents solutions to these specific challenges and describes a prototype system implementation. As agent coordination is the key component in conducting multi-agent text classification, two agent coordination protocols, namely blackboard-bidding protocol and adaptive-blackboard protocol, are proposed in the study. To analyze the performance of the distributed approach a comparative evaluation methodology is described, which treats outcome of a centralized approach as baseline performance. A series of experiments was conducted in a simulation environment. The simulation environment permitted manipulation of independent variables such as scalability and coordination strategy, and investigation of the impact on two critical dependent variables, namely efficiency and effectiveness. There were three critical findings. First, in dealing with automatic text classification the multi-agent approach can achieve improved system efficiency while maintaining classification effectiveness comparable to a centralized approach. Second, the agent protocols were effective in coordinating the text classification activities of distributed agents. Third, the application of content-based adaptive learning for acquiring knowledge about the agent community reduced communication cost and improved system efficiency.
An Efficient Uncertainty- and Skew-aware Methodology for Clock Tree Synthesis and Analysis
Authors: Vineet Wason, Rajeev Murgai, WilliamW. Walker
Venue: Proceedings of the 20th International Conference on VLSI Design held jointly with 6th International Conference: Embedded Systems (2007)

The effect of variations (process, voltage, temperature, and crosstalk) on circuit delay is increasing with technology scaling. As a result, the timing uncertainty of clock signal is increasing. In this paper, an efficient methodology for clock timing uncertainty- and skew-aware clock tree synthesis and analysis is proposed. We first present a statistical and less pessimistic methodology (as compared to the traditional static timing analysis (STA) methodology) for computing the clock timing uncertainty under the impact of parameter variations (process, voltage, temperature, and crosstalk). We also devise a technique to synthesize a clock tree that has zero skew and on which uncertainty can be computed efficiently. Finally, using the proposed uncertainty analysis algorithm, a post-processing scheme to re-analyze the critical paths reported by traditional STA is presented. We applied our zero-skew tree synthesis algorithm on a real industrial design. With our analysis methodology, the worst-case timing uncertainty on this tree was reduced from 388ps (used by traditional STA tools) to 63ps.
LEGO Robot Programming Exercise Support for Problem Solving Learning with Game Strategy Planning Tools
Authors: Hiroyuki Tominaga, Yohei Onishi, Toshihiro Hayashi, Toshinori Yamasaki
Venue: Proceedings of the The First IEEE International Workshop on Digital Game and Intelligent Toy Enhanced Learning (2007)

In an introduction to C programming exercise, it is important for college students to promote their interest and motivation. The goal of programming exercise is to obtain the skill for problem solving by algorithmic thinking and program implementation. A teacher must give them attractive and concrete subjects. Robot contest and group collaboration is one of the suitable styles for the purpose. We propose a game programming exercise using a simple robot kit LEGO Mindstorms. We are developing support environment GoalPost. In this paper, we introduce a framework of group programming exercise as a competition event with game-like problems for LEGO robot. Students learn to design their game strategy and realize it as an effective program. We discuss the four support levels of strategy design based on stepwise refinement. We offer support tools corresponding to visual representation product for each level. The aim of our research is to improve applicative ability and challenging activity of students through group works for the goal.
On the scalability of storage sub-system back-end network
Authors: Yan Li, Tim Courtney, Roland N. Ibbett, Nigel Topham
Venue: Proceedings of the 5th USENIX conference on File and Storage Technologies (2007)

The aim of this on-going work is to study the scalability of the back-end network of storage sub-systems in terms of the number of disks that can be linked to the network. It is well known that without considering the limitation of back-end network, increasing the number of disks in a RAID based storage system will increase the parallelism, and so can lead to a higher performance. Moreover, to save money on the back-end network, it is common practice to scale the number of disks rather than the number of independent access pathways. However, in a real system there is a limitation on the scale of storage sub-systems (controller cache size and number of disks that can be included in one system) due to the limitation of interconnection network. This is because the back-end interconnection networks are shared by all the disks and the RAID controllers in a storage sub-system. The more disks are added to the system, the higher the contention for the shared media. When the number of disks and cache size in a RAID system reaches a certain threshold, there will be no further gain in performance by adding more disk or cache due to the saturation of the back-end network. Therefore, in order to design a scalable storage sub-system it is critical to study the saturation characteristics and scalability of the back-end network. Previous work has focussed on sequential accesses only when working out when the back-end network becomes saturated, this does not represent a 'normal' workload. This work uses a workload based on the Storage Performance Council SPC-1 benchmark and so uses a representative loading.
Factored sparse inverse covariance matrices
Authors: J. A. Bilmes
Venue: Proceedings of the Acoustics, Speech, and Signal Processing, 2000. on IEEE International Conference - Volume 02 (2000)

Most HMM-based speech recognition systems use Gaussian mixtures as observation probability density functions. An important goal in all such systems is to improve parsimony. One method is to adjust the type of covariance matrices used. In this work, factored sparse inverse covariance matrices are introduced. Based on U'DU factorization, the inverse covariance matrix can be represented using linear regressive coefficients which 1) correspond to sparse patterns in the inverse covariance matrix (and therefore represent conditional independence properties of the Gaussian), and 2), result in a method of partial tying of the covariance matrices without requiring non-linear EM update equations. Results show that the performance of full-covariance Gaussians can be matched by factored sparse inverse covariance Gaussians having significantly fewer parameters.
Service Provider Implementation of SIP Regarding Security
Authors: Vesselin Tzvetkov, Holger Zuleger
Venue: Proceedings of the 21st International Conference on Advanced Information Networking and Applications Workshops - Volume 01 (2007)

The rapid growth of the SIP implementations clearly shows that the classical PSTN network will be exchanged by internet telephony. All Service Providers (SP) are currently deploying SIP infrastructure for offering the next generation networks. The implementations and network concepts used by the SP are different then the original designed in SIP standard. The main SP reasons are protecting their network, high number of customers, service quality quarantine and duties to the executive power. The security aspects in VoIP are generally secondary and planned for the coming years, since at first stage the target is launching the service on time. In this paper we are showing the current provider's SIP implementations and giving the motivation for this structure. Then we are analyzing the possibilities for securing the communication involving the existing standards. There are many security layers and objectives in the SIP networks to be considered. Some of them are practically not possible in the SP network and other are not reasonable. In this paper we giving the understanding, what can be done and how the different security mechanisms are interacting. At the end recommendation for protecting the SIP communication are made.
Fairplay—a secure two-party computation system
Authors: Dahlia Malkhi, Noam Nisan, Benny Pinkas, Yaron Sella
Venue: Proceedings of the 13th conference on USENIX Security Symposium - Volume 13 (2004)

Advances in modern cryptography coupled with rapid growth in processing and communication speeds make secure two-party computation a realistic paradigm. Yet, thus far, interest in this paradigm has remained mostly theoretical. This paper introduces Fairplay [28], a full-fledged system that implements generic secure function evaluation (SFE). Fairplay comprises a high level procedural definition language called SFDL tailored to the SFE paradigm; a compiler of SFDL into a one-pass Boolean circuit presented in a language called SHDL; and Bob/Alice programs that evaluate the SHDL circuit in the manner suggested by Yao in [39]. This system enables us to present the first evaluation of an overall SFE in real settings, as well as examining its components and identifying potential bottlenecks. It provides a test-bed of ideas and enhancements concerning SFE, whether by replacing parts of it, or by integrating with it. We exemplify its utility by examining several alternative implementations of oblivious transfer within the system, and reporting on their effect on overall performance.
A New Spatio-Temporal Predictor for Motion Estimation in H.264 Video Coding
Authors: Spyridon K. Kapotas, Athanassios N. Skodras
Venue: Proceedings of the Eight International Workshop on Image Analysis for Multimedia Interactive Services (2007)

The new JVT H.264 video coding standard is becoming the dominant standard, mainly due to its high coding efficiency. Among all modules in the encoder, motion estimation plays a key role since it can significantly affect the output quality of an encoded sequence. However, motion estimation requires a significant part of the encoding time. Thus, various fast motion estimation algorithms have been proposed. The H.264 reference encoder has currently adopted three fast motion estimation algorithms. These algorithms aim at reducing the search area by predicting the search points using suitable predictors. In this paper we propose a new spatio-temporal predictor and we study the effectiveness of different predictors in order to find out whether these predictors truly contribute to the decrease of motion estimation time without affecting video quality and adding undesirable complexity to the encoder.
A model for peer and student involvement in course assessment
Authors: S. Sheppard
Venue: Proceedings of the Frontiers in Education Conference,1997. on 27th Annual Conference. Teaching and Learning in an Era of Change. - Volume 01 (1997)

This paper discusses a protocol and rationale for peer and student involvement in the assessment of courses in engineering at Stanford University, USA. The protocol is based upon elements of good teaching practice, and on standards for peer review as used in journal publication. It has been "prototyped" in nine engineering courses over the past two years and has generally been found to be a good mechanism for near real-time monitoring that creates constructive feedback for teaching and learning quality control. Major features of this ongoing project are summarized, including faculty attitudes and required time commitment.
Mapping Modern Science Using Co-citation Analysis
Authors: Ayaka SAKA, Masatsura IGAMI
Venue: Proceedings of the 11th International Conference Information Visualization (2007)

Bibliometric analysis is used as a measuring activity technique for basic research. There are many country level analyses of trends in scientific publications. These analyses give us an understanding of the macro-scale character of scientific activities. However, it is difficult to capture the qualitative evolution of scientific activities through them. In this regard, a meso-scale analysis of science activities, i.e., analysis of "research areas", is suitable for grasping qualitative changes in scientific activities. In this study, we develop a new method for mapping science at the research area level. Our method consists of two parts: constructing research areas from scientific publications and content analysis by experts. Research areas are explored through a co-citation analysis, and a map of science was generated to analyze how research areas relate to each other. This method contributes to endeavours to understand and track the changing nature of science.
On the Rearrangeability of Reverse Shuffle/Exchange Networks
Authors: B. Park, K. Watson
Venue: Proceedings of the 1994 International Conference on Parallel Processing - Volume 01 (1994)

This paper proposes a new rearrangeable algorithm in a multistage reverse shuffle/exchange network. Currently, the best upper bound for the rearrangeability of a shuffle/exchange network in nonsymmetric networks is 3logN-3 stages. We describe the rearrangeability of reverse shuffle/exchange multistage interconnection network on every arbitrary permutation with N\leqslant16. It can be established by setting two more stages in the middle stage of the network to allow the reduced network to be topological equivalent to a class of rearrangeable networks. The results enable us to establish an upper bound, 2logN+l stages for reverse shuffle/exchange network with N\leqslant16, and leads to the possibility of this bound when N\ge16.
Modeling of Pinus Massoniana Based Morphological Architecture
Authors: Liyu Tang, Chongcheng Chen, Qinmin Wang, Jingjing Sun
Venue: Proceedings of the 16th International Conference on Artificial Reality and Telexistence--Workshops (2006)

In order to make 3D model representing Pinus Massoniana more realistic, field investigation and measurements were conducted in Wuyi Plantation in Zhangping City, Fujian Province, P.R. China. We measured parameters characteristic of Pinus Massoniana aerial architecture, then analyzed and quantified relationship between plant components and growth law. Based on the local-to-global model, the tree was decomposed into three components: a main trunk, several levels of brunches and leaves. We used above derived parameters to depict the structure and shape characteristics of Pinus Massoniana. Combined with polyhedron Geometric modeling and parameterized procedural modeling, a parameterized procedural tree model is given with a hybrid representation method. Implementation of the interactive modeling tool was written in Visual C++, using OpenGL libraries. The model could reconstruct Pinus Massoniana at different ages by modifying parameters. And the same time, the 3D Pinus Massoniana scene was constructed by populating tree models in the digital elevation model.
Linux at the Chasm
Authors: Don Rosenberg
Venue: Proceedings of the 3rd annual conference on Atlanta Linux Showcase - Volume 3 (1999)

Linux is moving through the Technology Adoption Cycle and gathering strength for a leap across the Chasm to Phase III, the Early Majority; a sign that Linux is already in Phase II is that large companies are implementing internal Linux projects. The Chasm must be crossed by a niche strategy, because Linux and the general user are not yet ready for each other. Hardware is one stage: Internet appliances, multi-processor servers, and embedded systems devices, will gain the OS more widespread use, but only when software applications begin to spread across companies in a niche, instead of being internal projects, will we see an application niche strategy begin to form and succeed. Software connected with POS systems is one likely candidate for this transition. Unfortunately, Linux cannot plan and marshal this Chasm crossing, nor can it manage public perception of itself. Furthermore, it will probably be 18-24 months before the software infrastructure (e.g., GUI tools for developers; file filters) is in place to support a widespread software movement. Likewise, support is not just setting up telephone help desks, but also providing enough integrators to help medium-sized businesses implement Linux as it passes through the niche stage; integrators and UNIX/Linux experts are scarcely overlapping groups. World Domination will take a while, and there is a danger that constant hyping of Linux by the media will create unrealistic expectations.
In-network computation in wireless sensor networks
Authors: P. R. Kumar
Venue:  (2006)

Wireless sensor networks are networks of devices which collaborate to perform distributed sensing, processing, and possibly even actuation tasks. This thesis is a study of distributed tasks which require in-network communication and processing. First, we study how distributed computation can be efficiently carried out over wireless networks. We formulate the problem as one of determining the optimal rate or frequency at which symmetric functions of data distributed throughout the network can be computed at a collection center. Under a deterministic framework and packet collision-based model, we derive scaling laws with respect to network size which characterize the maximum achievable computational throughput for different subclasses of symmetric functions over connectivity graphs of different topologies. The results indicate that the maximum rate can be exponentially higher in a multihop network in comparison to a single hop network, due to the ability to compress data in-network. There is also an exponential increase in the maximum computational throughput for type-sensitive functions in comparison to type-threshold functions, which are subclasses of symmetric functions that include most statistical functions of interest. Next, we study another important metric in sensor networks, which is network lifetime. We consider a formulation of maximizing network lifetime given the simple task of downloading different quantities of data over nodes with different energy levels. We reduce the problem of choosing lifetime optimal routes to a linear program, and derive closed form solutions for some simple regular network topologies. In the final part of the thesis, we consider the problem of clock synchronization over multihop networks, which is a specific instance of a network task requiring distributed computation. We analyze a clock synchronization approach which leads to a distributed vector estimation problem based on noisy estimates of clock differences of pairs of nodes which can directly exchange packets. We establish connections between the error variance of optimal least-squares clock synchronization and resistances in electrical networks. We propose and analyze the convergence time of a distributed iterative algorithm to compute the optimal estimates. We also propose ways of exploiting the network connectivity graph structure in order to speed up computation.
Performance implications of multiple pointer sizes
Authors: Jeffrey C. Mogul, Joel F. Bartlett, Robert N. Mayo, Amitabh Srivastava
Venue: Proceedings of the USENIX 1995 Technical Conference Proceedings on USENIX 1995 Technical Conference Proceedings (1995)

Many users need 64-bit architectures: 32-bit systems cannot support the largest applications, and 64-bit systems perform better for some applications. However, performance on some other applications can suffer from the use of large pointers; large pointers can also constrain feasible problem size. Such applications are best served by a 64-bit machine that supports the use of both 32-bit and 64-bit pointer variables. This paper analyzes several programs and programming techniques to understand the performance implications of different pointer sizes. Many (but not all) programs show small but definite performance consequences, primarily due to cache and paging effects.