ppxscal/embedding_network huggingface dataset:
A study on the metallic electrode materials of the SAW devices
Authors: Huann-Wu Chiang, Jun-Xian Wu
Venue: Proceedings of the 9th International Conference on Circuits (2005)

In this study, the properties of the metallic electrodes on the piezoelectric substrates were investigated. By using nano-indentation technique, the hardness and elastic modulus of the electrode film were measured and it was found that they were varied with electrode type. After 150°C high temperature storage test, the microstructure and consequently, the hardness and the elastic modulus were slightly changed. In addition, the adhesion between electrode film and substrate was also tested.
ICT implementation in the health-care sector: effective stakeholders&#x2019; engagement as the main precondition of change sustainability
Authors: Rasa Juciute
Venue: AI Society (2008)

As modern information and communication technologies (ICT) now offer new possibilities for improving almost every aspect of health care, their implementation is a very relevant and fast accelerating process around Europe and internationally. The processes themselves vary greatly from scattered single initiatives of various IT solutions to large national programmes. Often treated as purely technical in nature, ICT implementation in health care should gravitate towards the &#x201c;softer/complex&#x201d; i.e. people-related issues end of the change. The approach taken by the Informing Healthcare programme in Wales broadens understanding on the value that engagement of stakeholders can bring to the process.
Using Network Density as a New Parameter to Estimate Distance
Authors: Freddy López Villafuerte, Kirsten Terfloth, Jochen Schiller
Venue: Proceedings of the Seventh International Conference on Networking (2008)

A wireless sensor network consists of a large quantity of small, low-cost sensor nodes that are limited in terms of memory, available energy and processing capacity. Generally, these sensor nodes are distributed in space to obtain physical parameters such as temperature, humidity, vibration or light conditions, and transmit the measured values to a central entity. The measurements are tagged with the corresponding location of the nodes in the network and the time of sampling, to enable a view on the value distribution in space and time later on. Positioning of wireless sensor nodes without dedicated hardware is an open research question. Especially in the domain of embedded networked sensors, many applications rely on spatial information to relate collected data to the location of its origin. As a first step towards localization, an estimation of the distance between two nodes is often carried out to determine their positions. So far, the majority of approaches therefore explore physical properties of radio signals such as the strength of a received signal or its trip time. However, this is problematic since either the complexity on the software or on the hardware side is not adequate for embedded systems, or the approaches lack the required accuracy. In this paper we present the WDNI algorithm (Weighted Density of Node Intersection) to determine the distance between two nodes, relying solely on the investigation of local node densities. To evaluate the accuracy of this algorithm, we ran extensive simulations and experimented with different testbed setups using real sensor nodes, and finally compared WDNI to a range-free distance estimation algorithm based the analysis of RSSI values.
A Tunable Clock Buffer for Intra-die PVT Compensation in Single-Edge Clock (SEC) Distribution Networks
Authors: Jeff Mueller, Resve Saleh
Venue: Proceedings of the 9th international symposium on Quality Electronic Design (2008)

As processes shrink, the on-chip variability grows and this variation causes clock skew to rapidly consume a larger-and-larger percentage of the clock period. New techniques to reduce skew are required, but post-silicon clock adjustments will still be necessary to compensate for intra-die PVT variations. A relatively new technique for skew reduction, called Single-Edge Clocking (SEC), focuses clock buffer design on the critical edge by using alternating strong pull-up and strong pull-down buffers. In this paper, a new digitally tuned buffer for SEC clock networks is presented. It is based on a single-sided starved inverter configuration and is tuned using a 3-bit thermometer code. Sizing issues and skew reduction achievable in the presence of PVT variations are presented. The overhead in terms of layout area and current consumption for this new tunable buffer is only a small fraction of other tunable buffer designs.
Integration of heterogeneous networking testbeds
Authors: R. Mahindra, G. Bhanage, G. Hadjichristofi, S. Ganu, P. Kamat, I. Seskar, D. Raychaudhuri
Venue: Proceedings of the 4th International Conference on Testbeds and research infrastructures for the development of networks & communities (2008)

As networking research expands into new frontiers, the research community has felt a need for a heterogeneous networking research infrastructure to experiment with the interaction and integration of different types of networks, and to test the performance of various networking protocols in realistic environments. This requirement has led to the Global Environment for Network Innovations (GENI) initiative to create a global infrastructure for conducting networking experiments across diverse substrates such as wired (local and wide-area), wireless, sensor and cellular networks. In this paper, we discuss and present two models for building such an experimental infrastructure. The first model enables a wired testbed to link with wireless edge nodes during an experiment, whereas the second model enables a wireless testbed to link to wired testbeds. Proof-of-concept experiments are also presented reinforcing the usefulness of the models in terms of facilitating experiments over the integrated heterogeneous infrastructure.
Combining statistical alignment and phylogenetic footprinting to detect regulatory elements
Authors: Rahul Satija, Lior Pachter, Jotun Hein
Venue: Bioinformatics (2008)

Motivation: Traditional alignment-based phylogenetic footprinting approaches make predictions on the basis of a single assumed alignment. The predictions are therefore highly sensitive to alignment errors or regions of alignment uncertainty. Alternatively, statistical alignment methods provide a framework for performing phylogenetic analyses by examining a distribution of alignments. Results: We developed a novel algorithm for predicting functional elements by combining statistical alignment and phylogenetic footprinting (SAPF). SAPF simultaneously performs both alignment and annotation by combining phylogenetic footprinting techniques with an hidden Markov model (HMM) transducer-based multiple alignment model, and can analyze sequence data from multiple sequences. We assessed SAPF's predictive performance on two simulated datasets and three well-annotated cis-regulatory modules from newly sequenced Drosophila genomes. The results demonstrate that removing the traditional dependence on a single alignment can significantly augment the predictive performance, especially when there is uncertainty in the alignment of functional regions. Availability: SAPF is freely available to download online at http://www.stats.ox.ac.uk/~satija/SAPF/ Contact: satija@stats.ox.ac.uk Supplementary information: Supplementary data are available at Bioinformatics online.
Pose-encoded spherical harmonics for face recognition and synthesis using a single image
Authors: Zhanfeng Yue, Wenyi Zhao, Rama Chellappa
Venue: EURASIP Journal on Advances in Signal Processing (2008)

Face recognition under varying pose is a challenging problem, especially when illumination variations are also present. In this paper, we propose to address one of the most challenging scenarios in face recognition. That is, to identify a subject from a test image that is acquired under dierent pose and illumination condition from only one training sample (also known as a gallery image) of this subject in the database. For example, the test image could be semifrontal and illuminated by multiple lighting sources while the corresponding training image is frontal under a single lighting source. Under the assumption of Lambertian reflectance, the spherical harmonics representation has proved to be effective in modeling illumination variations for a fixed pose. In this paper, we extend the spherical harmonics representation to encode pose information. More specifically, we utilize the fact that 2D harmonic basis images at different poses are related by close-form linear transformations, and give a more convenient transformation matrix to be directly used for basis images. An immediate application is that we can easily synthesize a different view of a subject under arbitrary lighting conditions by changing the coefficients of the spherical harmonics representation. A more important result is an efficient face recognition method, based on the orthonormality of the linear transformations, for solving the above-mentioned challenging scenario. Thus, we directly project a nonfrontal view test image onto the space of frontal view harmonic basis images. The impact of some empirical factors due to the projection is embedded in a sparse warping matrix; for most cases, we show that the recognition performance does not deteriorate after warping the test image to the frontal view. Very good recognition results are obtained using this method for both synthetic and challenging real images.
A result-data offloading service for HPC centers
Authors: Henry Monti, Ali R. Butt, Sudharshan S. Vazhkudai
Venue: Proceedings of the 2nd international workshop on Petascale data storage: held in conjunction with Supercomputing '07 (2007)

Modern High-Performance Computing applications are consuming and producing an exponentially increasing amount of data. This increase has lead to a significant number of resources being dedicated to data staging in and out of Supercomputing Centers. The typical approach to staging is a direct transfer of application data between the center and the application submission site. Such a direct data transfer approach becomes problematic, especially for staging-out, as (i) the data transfer time increases with the size of data, and may exceed the time allowed by the center's purge policies; and (ii) the submission site may not be online to receive the data, thus further increasing the chances for output data to be purged. In this paper, we argue for a systematic data staging-out approach that utilizes intermediary data-holding nodes to quickly offload data from the center to the intermediaries, thus avoiding the peril of a purge and addressing the two issues mentioned above. The intermediary nodes provide temporary data storage for the staged-out data and maximize the offload bandwidth by providing multiple dataflow paths from the center to the submission site. Our initial investigation shows such a technique to be effective in addressing the above two issues and providing better QOS guarantees for data retrieval.
Towards hybrid last level caches for chip-multiprocessors
Authors: Li Zhao, Ravi Iyer, Mike Upton, Don Newell
Venue: ACM SIGARCH Computer Architecture News (2008)

As CMP platforms are widely adopted, more and more cores are integrated on to the die. To reduce the off-chip memory access, the last level cache is usually organized as a distributed shared cache. In order to avoid hot-spots, cache lines are interleaved across the distributed shared cache slices using a hash function. However, as we increase the number of cores and cache slices in the platform, this also implies that most of data references go to remote cache slices, thereby increasing the access latency significantly. In this paper, we propose a hybrid last level cache, which has some amount of private space and some amount of shared space on each cache slice. For workloads with no sharing, the goal is to provide more hits into the local slice while still keeping the overall miss rate low. For workloads with sufficient sharing, the goal is to allow more sharing in the last-level cache slice. We present hybrid last-level cache design options and study its hit/miss rate behavior for a number of important server applications and multi-programmed workloads. Our simulation results on running multi-programmed workloads based on SPEC CINT2000 as well as multithreaded workloads based on commercial server benchmarks (TPCC, SPECjbb, SAP and TPCE) show that this architecture is advantageous especially since it can improve the local hit rate significantly while keeping the overall miss rate similar to the shared cache.
Cascaded treemaps: examining the visibility and stability of structure in treemaps
Authors: Hao Lü, James Fogarty
Venue: Proceedings of graphics interface 2008 (2008)

Treemaps are an important and commonly-used approach to hierarchy visualization, but an important limitation of treemaps is the difficulty of discerning the structure of a hierarchy. This paper presents cascaded treemaps, a new approach to treemap presentation that is based in cascaded rectangles instead of the traditional nested rectangles. Cascading uses less space to present the same containment relationship, and the space savings enable a depth effect and natural padding between siblings in complex hierarchies. In addition, we discuss two general limitations of existing treemap layout algorithms: disparities between node weight and relative node size that are introduced by layout algorithms ignoring the space dedicated to presenting internal nodes, and a lack of stability when generating views of different levels of treemaps as a part of supporting interactive zooming. We finally present a two-stage layout process that addresses both concerns, computing a stable structure for the treemap and then using that structure to consider the presentation of internal nodes when arranging the treemap. All of this work is presented in the context of two large real-world hierarchies, the Java package hierarchy and the eBay auction hierarchy.
Gathering two stateless mobile robots using very inaccurate compasses in finite time
Authors: Masafumi Yamashita, Samia Souissi, Xavier Défago
Venue: Proceedings of the 1st international conference on Robot communication and coordination (2007)

This paper considers two asynchronous identical mobile robots in an environment devoid of any landmarks or common coordinate system. The robots, executing their own instance of the same algorithm, must cooperate to end up at the exact same location (not predetermined) within a finite time. The problem, known as gathering, is the simplest form of spontaneous agreement that can be reached between the robots. This simple problem is however notoriously impossible with two such robots. Surprisingly, the problem was shown to be solvable for three robots or more, adding a weak assumption to help break any potential symmetry in the system. Prior work has shown that the problem could be solved by letting each robot have access to some compass, provided that the divergence between the compasses is at most 45&deg;. The question remained open, however, as to whether the problem could still be solved with a larger divergence. In this paper, we present a distributed algorithm that solves the gathering problem with two asynchronous robots, when their compasses can differ by any angle less than 180&deg;, which is obviously the largest divergence for which the compasses can still bring any useful information.
Throttled Lazy Cancellation in Time Warp Parallel Simulation
Authors: Hussam M. Soliman Ramadan
Venue: Simulation (2008)

Time Warp parallel simulations need efficient schemes to cancel erroneous event messages in order to achieve acceptable performance levels. Lazy cancellation depends on delaying the cancellation of incorrect computations until rolled-back events are re-processed. An antimessage is then sent for cancellation only if an output message re-produced after rollback is found to be unequal to its counterpart produced before rollback. One drawback of this approach is that antimessages are sent too late to catch the wave of incorrect computations, which results in more rollbacks. In this paper, we suggest an enhanced lazy cancellation technique that aims to throttle incorrect computations. It asks logical processes (LPs) that have received any output messages, generated from the first execution of a rolled-back input event in some neighboring LP, to mark those messages as temporarily blocked. Those messages remain in a blocked state until it is later decided whether or not they must be cancelled. The receiving LP becomes blocked only after a blocked input message becomes the next message to process. After re-executing the rolled-back input event, the sending LP sends each of its receiving LPs either an `Unblock' message or an antimessage for each previously marked output message, depending on the result of the equality test of that output message's versions before and after rollback. Experimental results for a synthetic benchmark show that our technique can yield better performance than both lazy and aggressive cancellation.
Toward Spatial Window Queries over Continuous Phenomena in Sensor Networks
Authors: Guang Jin, Silvia Nittel
Venue: IEEE Transactions on Parallel and Distributed Systems (2008)

Recent research on sensor networks has focused on efficient processing of declarative SQL queries over sensor nodes. Users are often interested in querying an underlying continuous phenomenon, such as a toxic plume, while only discrete readings of sensor nodes are available. Therefore, additional information estimation methods are necessary to process the sensor readings to generate the required query results. Most estimation methods are computationally intensive, even when computed in a traditional centralized setting. Furthermore, energy and communication constraints of sensor networks challenge the efficient application of established estimation methods in sensor networks. In this paper, we present an approach using Gaussian Kernel estimation to process spatial window queries over continuous phenomena in sensor networks. The key contribution of our approach is using a small number of Hermite coefficients to approximate the Gaussian Kernel function for sub-clustered sensor nodes. As a result, our algorithm reduces the size of messages transmitted in the network by logarithmic order, thus, saving resources while still providing high quality query results.
An Optimal Solution of Byzantine Agreement in a Scale Free Network
Authors: Kuo-Qin Yan, Shun-Sheng Wang, Shu-Ching Wang
Venue: Proceedings of the 22nd International Conference on Advanced Information Networking and Applications - Workshops (2008)

With the fast development of Internet, in order to increase systematic operation ability, the distributed system has replaced the large-scale computer system gradually. In generally, the task in a distributed system must achieve an agreement. Such a unanimity problem is called the Byzantine Agreement (BA). The BA problem is one of the most important problems in designing a fault-tolerant distributed system. Traditionally, this problem was well formulated in a random network. However, in recently, many large complex networks have emerged and displayed a scale free feature. It is an important topic that can represent the structure of highly fault-tolerant ability in the Scale Free Network (SFN). In our research, the BA problem is revisited in a SFN. The proposed protocol uses the minimum number of message exchanges to reach an agreement within the distributed system while tolerating the maximum number of faulty components in SFN.
SOI-CMOS compatible low-power gas sensor using sputtered and drop-coated metal-oxide active layers
Authors: P. Ivanov, J. Laconte, J. P. Raskin, M. Stankova, E. Sotter, E. Llobet, X. Vilanova, D. Flandre, X. Correig
Venue: Microsystem Technologies (2005)

In this paper, a Silicon-On-Insulator (SOI) solid-state gas-sensor with an original design of a polysilicon loop-shaped microheater fabricated on a thin-stacked dielectric membrane is presented. The microheater ensures high thermal uniformity and very low power consumption (25&#x00a0;mW for heating at 400&#x00b0;C). Sensitive films are based on tin and tungsten oxides deposited either by RF sputtering or drop coating methods. The fabricated sensors are tested to a wide variety of contaminant species and promising results are obtained. The use of completely CMOS compatible TMAH-based bulk micro-machining techniques during the fabrication process, allows easy smart gas sensor integration in SOI-CMOS technology. This makes SOI-based gas-sensing devices particularly attractive for use in handheld battery-operated gas monitors.
Game-themed programming assignments: the faculty perspective
Authors: Kelvin Sung, Michael Panitz, Scott Wallace, Ruth Anderson, John Nordlinger
Venue: ACM SIGCSE Bulletin (2008)

We have designed and implemented game-themed programming assignment modules targeted specifically for adoption in existing introductory programming classes. These assignments are self-contained, so that faculty members with no background in graphics or gaming can selectively pick and choose a subset to combine with their own assignments in existing classes. This paper begins with a survey of previous results. Based on this survey, the paper summarizes the important considerations when designing materials for elective adoption. The paper then describes our design, implementation, and assessment efforts. Our result is a road map that guides faculty members in experimenting with game-themed programming assignments by incrementally adopting/customizing suitable materials for their classes.
Visibility volumes for interactive path optimization
Authors: Manohar B. Srikanth, P. C. Mathias, Vijay Natarajan, Prakash Naidu, Timothy Poston
Venue: The Visual Computer: International Journal of Computer Graphics (2008)

We describe a real-time system that supports design of optimal flight paths over terrains. These paths either maximize view coverage or minimize vehicle exposure to ground. A volume-rendered display of multi-viewpoint visibility and a haptic interface assists the user in selecting, assessing, and refining the computed flight path. We design a three-dimensional scalar field representing the visibility of a point above the terrain, describe an efficient algorithm to compute the visibility field, and develop visual and haptic schemes to interact with the visibility field. Given the origin and destination, the desired flight path is computed using an efficient simulation of an articulated rope under the influence of the visibility gradient. The simulation framework also accepts user input, via the haptic interface, thereby allowing manual refinement of the flight path.