ppxscal/embedding_network huggingface dataset:
Tighter estimation using bottom k sketches
Authors: Edith Cohen, Haim Kaplan
Venue: Proceedings of the VLDB Endowment (2008)

Summaries of massive data sets support approximate query processing over the original data. A basic aggregate over a set of records is the weight of subpopulations specified as a predicate over records' attributes. Bottom-k sketches are a powerful summarization format of weighted items that includes priority sampling [22], and the classic weighted sampling without replacement. They can be computed efficiently for many representations of the data including distributed databases and data streams and support coordinated and all-distances sketches. We derive novel unbiased estimators and confidence bounds for subpopulation weight. Our rank conditioning (RC) estimator is applicable when the total weight of the sketched set cannot be computed by the summarization algorithm without a significant use of additional resources (such as for sketches of network neighborhoods) and the tighter subset conditioning (SC) estimator that is applicable when the total weight is available (sketches of data streams). Our estimators are derived using clever applications of the Horvitz-Thompson estimator (that is not directly applicable to bottom-k sketches). We develop efficient computational methods and conduct performance evaluation using a range of synthetic and real data sets. We demonstrate considerable benefits of the SC estimator on larger subpopulations (over all other estimators); of the RC estimator (over existing estimators for weighted sampling without replacement); and of our confidence bounds (over all previous approaches).
Logic-based robot control in highly dynamic domains
Authors: Alexander Ferrein, Gerhard Lakemeyer
Venue: Robotics and Autonomous Systems (2008)

In this paper, we present the robot programming and planning language Readylog, a Golog dialect, which was developed to support the decision making of robots acting in dynamic real-time domains, such as robotic soccer. The formal framework of Readylog, which is based on the situation calculus, features imperative control structures such as loops and procedures, allows for decision-theoretic planning, and accounts for a continuously changing world. We developed high-level controllers in Readylog for our soccer robots in RoboCup's Middle-size league, but also for service robots and for autonomous agents in interactive computer games. For a successful deployment of Readylog on a real robot it is also important to account for the control problem as a whole, integrating the low-level control of the robot (such as localization, navigation, and object recognition) with the logic-based high-level control. In doing so, our approach can be seen as a step towards bridging the gap between the fields of robotics and knowledge representation.
Cough sound analysis to identify respiratory infection in pigs
Authors: Sara Ferrari, Mitchell Silva, Marcella Guarino, Jean Marie Aerts, Daniel Berckmans
Venue: Computers and Electronics in Agriculture (2008)

Cough sound detection is a central element to diagnose common respiratory diseases like pneumonia in intensive pig farming. The aim of this work is the description of acoustic features of cough sounds originating from a lung infection and the comparison between these kind of cough sounds with those provoked by inhalation of citric acid. Coughs have been recorded from infected animals in field conditions (pneumonia) and from healthy animals in laboratory (induced). After having completed the classification, the investigation on infectious and non-infectious cough sounds has involved the main differences among acoustic parameters, like the Root Mean Square (RMS), the peak frequency (Hz), the duration and the time occurring between successive coughs in a cough attack. The results show a significant difference among the RMS, peak frequency and duration in cough sounds from healthy and infected animals. RMS was 0.215 for healthy animals and 0.124 for infected ones (P=0). Non-infectious coughs have an average peak frequency of 1600Hz, while infectious coughs stand around 600Hz. Also the length of sounds is significantly lower (P
DSP/FPGA-based Controller Architecture for Flexible Joint Robot with Enhanced Impedance Performance
Authors: J. B. Huang, Z. W. Xie, H. Liu, K. Sun, Y. C. Liu, Z. N. Jiang
Venue: Journal of Intelligent and Robotic Systems (2008)

Some practical issues associated with enhancing the Cartesian impedance performance of flexible joint manipulator are investigated. A digital signal processing/field programmable gate array (DSP/FPGA) structure is proposed to realize the singular perturbation based impedance controller. To increase the bandwidth of torque control and minimize the joint torque ripple, boundary layer system and field-oriented control (FOC) are fully implemented in a FPGA of each joint. The kernel of the hardware system is a peripheral component interface (PCI)-based high speed floating-point DSP for the Cartesian level control, and FPGA for high speed (200 us cycle time) multipoint low-voltage differential signaling (M-LVDS) serial data bus communication between robot Cartesian level and joint level. Experimental results with a four-degree-of-freedom flexible-joint manipulator under constrained-motion task, demonstrate that the controller architecture can enhance the robot impedance performance effectively.
On the secure creation, organisation and discovery of topics in distributed publish&#47;subscribe systems
Authors: Shrideep Pallickara, Geoffrey Fox, Harshawardhan Gadgil
Venue: International Journal of High Performance Computing and Networking (2008)

Publish/Subscribe infrastructures have gained significant traction recently with several specifications such as the Java Message Service (JMS), WS-Eventing and WS-Notification. In this paper we present a scheme for the secure organisation and discovery of topics in distributed publish/subscribe systems. The scheme also addresses security related issues such as authorisation and provenance in the discovering these topics. Our experimental results demonstrate the feasibility of this framework. We have also included a scheme for the organisation and discovery of topics that have hierarchical relationships and those that are part of a collection of topics in dynamic, high-flux publish/subscribe environments.
Original papers: Design and development of data mart for animal resources
Authors: Anil Rai, Vipin Dubey, K. K. Chaturvedi, P. K. Malhotra
Venue: Computers and Electronics in Agriculture (2008)

Planners, researchers, development agencies and farmers require information on animal resources for further studies and evolving realistic strategies for improvement and rearing of livestock and poultry. Data is also required for keeping watch on prices and movement of animal products, animal feed and establishment of services such as veterinary hospitals, artificial insemination (AI) centers, meat and dairy industries, etc. Further, there is a need to study animal resources in relation to other aspects of agriculture, such as soils, vegetation, agro-meteorology, socio-economic, land use, water resources for overall development of agricultural production system. Indian Agricultural Statistics Research Institute (IASRI), New Delhi has designed and implemented a Central Data Warehouse (CDW) under a National Agricultural Technology Project (NATP) Mission Mode sub-project entitled ''Integrated National Agricultural Resources Information System (INARIS)''. In this CDW, 13 different data marts related to various subjects in agriculture were designed, implemented and integrated. In this article, attempt was made to discuss concepts and problems of dimensional modeling of the animal data mart in relation to available source data on livestock resources in the country. Alternative solutions to specific problems were also discussed along with the solution implemented for modeling of this data mart. The complete process of building On-line Analytical Processing (OLAP) system for research managers including inbuilt technique of data quality and consistency checks to be implemented is being described with special reference to animal resource management. This article will provide guidelines for design and development of similar complex data marts in agricultural sector, particularly in the field of livestock management.
Synthetic satellite imagery for current and future environmental satellites
Authors: Lewis D. Grasso, Manajit Sengupta, John F. Dostalek, Renate Brummer, Mark Demaria
Venue: International Journal of Remote Sensing (2008)

During the next decade, data from a new generation of US geostationary and polar orbiting satellites will become available. To prepare for these data, representative imagery of these satellites is desirable. Two independent methods have been developed to create imagery from future satellites before they are placed into orbit. One method uses data from current operational and experimental satellites. Data obtained this way are referred to as simulated imagery. Another method generates satellite imagery by using numerical models. Data obtained by this method are referred to as synthetic imagery. Each method has some weaknesses that can be overcome by using both methods together. Synthetic imagery for two future US sensors is introduced in this paper. Emphasis is placed on a severe thunderstorm event.
Coherent coupling of feedback loops
Authors: Yung-Keun Kwon, Kwang-Hyun Cho
Venue: Bioinformatics (2008)

Motivation:It is widely accepted that cell signaling networks have been evolved to be robust against perturbations. To investigate the topological characteristics resulting in such robustness, we have examined large-scale signaling networks and found that a number of feedback loops are present mostly in coupled structures. In particular, the coupling was made in a coherent way implying that same types of feedback loops are interlinked together. Results: We have investigated the role of such coherently coupled feedback loops through extensive Boolean network simulations and found that a high proportion of coherent couplings can enhance the robustness of a network against its state perturbations. Moreover, we found that the robustness achieved by coherently coupled feedback loops can be kept evolutionarily stable. All these results imply that the coherent coupling of feedback loops might be a design principle of cell signaling networks devised to achieve the robustness. Contact: ckh@kaist.ac.kr Supplementary information: Supplementary data are available at Bioinformatics online.
ASTER-based study of the night-time urban heat island effect in Metro Manila
Authors: M. Tiangco, A. M. F. Lagmay, J. Argete
Venue: International Journal of Remote Sensing (2008)

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) was used to derive land surface temperatures to quantify the night-time urban heat island (UHI) effect in Metro Manila. Temperature differences between Metro Manila and its adjacent rural towns were compared to determine heat island intensity and analyse spatial variation of surface temperature. Transects were drawn across from the rural to the urban region to characterize the UHI profile and the Normalized Difference Vegetation Index (NDVI) was used to examine the relationship between amount of vegetation and temperature. The thermal images revealed the highest UHI intensity to be 2.96°C with the presence of a heat island existing in the central part of the city. The transects described the cross-sectional heat island profile characterized by gradients of 'cliffs', 'plateaus' and a 'peak' occurring in the city centre. The study also showed an inverse relationship between NDVI and temperature, which suggests that increasing the amount of plants in cities can reduce the UHI effect.
Performance improvement of synchronous multiuser communication systems by using process sharing techniques
Authors: Mohd Fadzil Ain, Farid Ghani, Mutamed Khatib, Syed Idris Syed Hassan
Venue: WSEAS TRANSACTIONS on COMMUNICATIONS (2007)

This paper presents new techniques that improve the performance of Code Division Multiple Access (CDMA) system for transmission of digital data over time varying channels such as high frequency mobile channels. The main ideas presented here are to share the equalization process between the transmitter and the receiver of the system with a certain ratio that maximize the signal to noise ratio (SNR). The channel characteristics should be known at the transmitter and receiver, it is the requirement for all systems that employ coding at the transmitter.
A comprehensive analysis of mobility management in MPLS-based wireless access networks
Authors: Rami Langar, Nizar Bouabdallah, Raouf Boutaba
Venue: IEEE/ACM Transactions on Networking (TON) (2008)

Efficient mobility management is one of the major challenges for next-generation mobile systems. Indeed, a mobile node (MN) within an access network may cause excessive signaling traffic and service disruption due to frequent handoffs. The two latter effects need to be minimized to support quality-of-service (QoS) requirements of emerging multimedia applications. In this perspective, we propose in this paper a new mobility management scheme designed to track host mobility efficiently so as to minimize both handoff latency and signaling cost. Building on and enhancing Mobile IP and taking advantage of MPLS traffic engineering capability, three mechanisms (FH-, FC- and MFC-Micro Mobile MPLS) are introduced. In order to assess the efficiency of our proposals, all protocols are compared. To achieve this, we develop analytical models to evaluate the signaling cost and link usage for both two-dimensional and one-dimensional mobility models. Additional mathematical models are also provided to derive handoff latency and packet loss rate. Numerical and simulation results show that the proposed mechanisms can significantly reduce the registration updates cost and provide low handoff latency and packet loss rate under various scenarios.
Error Correcting Output Coding-Based Conditional Random Fields for Web Page Prediction
Authors: Yong Zhen Guo, Kotagiri Ramamohanarao, Laurence A. F. Park
Venue: Proceedings of the 2008 IEEE/WIC/ACM International Conference on Web Intelligence and Intelligent Agent Technology - Volume 01 (2008)

Web page prefetching has been used efficiently to reduce the access latency problem of the Internet, its success mainly relies on the accuracy of Web page prediction. As powerful sequential learning models, Conditional Random Fields (CRFs) have been used successfully to improve the Web page prediction accuracy when the total number of unique Web pages is small. However, because the training complexity of CRFs is quadratic to the number of labels, when applied to a website with a large number of unique pages, the training of CRFs may become very slow and even intractable. In this paper, we decrease the training time and computational resource requirements of CRFs training by integrating error correcting output coding (ECOC) method. Moreover, since the performance of ECOC-based methods crucially depends on the ECOC code matrix in use, we employ a coding method, Search Coding, to design the code matrix of good quality.
Alignment of liquid crystals on a topographically nano-patterned polymer surface prepared by a soft-imprint technique
Authors: Min Ju Park, O Ok Park
Venue: Microelectronic Engineering (2008)

In this study, we have fabricated polyacrylate substrates having a nano-patterned surface topography using a soft-imprint technique. The planar alignment of liquid crystals (LCs) along the direction of nanogrooves has been generated. Twisting behavior of nematic LCs has been also observed with a perpendicularly assembled LC cell and the cell parameters can be estimated by using the Soutar and Lu method. By comparing the anchoring energies obtained, accordingly, it has been demonstrated that the polymer nanogroove pattern has a comparable influence on LC alignment to the conventional rubbing process. It has been also shown that the artificial topography of the line grooves on the conventionally rubbed surface has a significant influence on the anchoring stability of the LC molecules.
Discovering regulatory motifs in the Plasmodium genome using comparative genomics
Authors: Jie Wu, Douglas H. Sieglaff, Joshua Gervin, Xiaohui S. Xie
Venue: Bioinformatics (2008)

Motivation: Understanding gene regulation in Plasmodium, the causative agent of malaria, is an important step in deciphering its complex life cycle as well as leading to possible new targets for therapeutic applications. Very little is known about gene regulation in Plasmodium, and in particular, few regulatory elements have been identified. Such discovery has been significantly hampered by the high A-T content of some of the genomes of Plasmodium species, as well as the challenge in associating discovered regulatory elements to gene regulatory cascades due to Plasmodium's complex life cycle. Results: We report a new method of using comparative genomics to systematically discover motifs in Plasmodium without requiring any functional data. Different from previous methods, our method does not depend on sequence alignments, and thus is particularly suitable for highly divergent genomes. We applied our method to discovering regulatory motifs between the human parasite, P.falciparum, and its rodent-infectious relative, P.yoelii. We also tested our procedure against comparisons between P.falciparum and the primate-infectious, P.knowlesi. Our computational effort leads to an initial catalog of 38 distinct motifs, corresponding to over 16 200 sites in the Plasmodium genome. The functionality of these motifs was further supported by their defined distribution within the genome as well as a correlation with gene expression patterns. This initial map provides a systematic view of gene regulation in Plasmodium, which can be refined as additional genomes become available. Availability: The new algorithm, named motif discovery using orthologous sequences (MDOS), is available at http://www.ics.uci.edu/~xhx/project/mdos/. Contact: xhx@ics.uci.edu Supplementary information:Supplementary data are available at Bioinformatics online.
Performance of wideband mobile channel on synchronous DS-CDMA
Authors: Hamed D. Al-Sharari
Venue: WSEAS TRANSACTIONS on COMMUNICATIONS (2007)

Direct-sequence code-division multiple access (DS-CDMA) is currently the subject of much research as it is a promising multiple access capability for third and fourth generations mobile communication systems. The synchronous DS-CDMA system is well known for eliminating the effects of multiple access interference (MAI) which limits the capacity and degrades the BER performance of the system. In this paper, we investigate the bit error rate (BER) performance of a synchronous DS-CDMA system over a wideband mobile radio channel. The BER performance is affected by the difference in path length ΔL and the number of arriving signals N. Furthermore, the effect of these parameters is examined on the synchronous DS-CDMA system for different users' number as well as different processing gain Gp. The promising simulation results showed the possibility of applying this system to the wideband mobile radio channel.
Adaptive collaborative filtering
Authors: Markus Weimer, Alexandros Karatzoglou, Alex Smola
Venue: Proceedings of the 2008 ACM conference on Recommender systems (2008)

We present a flexible approach to collaborative filtering which stems from basic research results. The approach is flexible in several dimensions: We introduce an algorithm where the loss can be tailored to a particular recommender problem. This allows us to optimize the prediction quality in a way that matters for the specific recommender system. The introduced algorithm can deal with structured estimation of the predictions for one user. The most prominent outcome of this is the ability of learning to rank items along user preferences. To this end, we also present a novel algorithm to compute the ordinal loss in O(n log(n)) as apposed to O(n2). We extend this basic model such that it can accommodate user and item offsets as well as user and item features if they are present. The latter unifies collaborative filtering with content based filtering. We present an analysis of the algorithm which shows desirable properties in terms of privacy needs of users, parallelization of the algorithm as well as collaborative filtering as a service. We evaluate the algorithm on data provided by WikiLens. This data is a cross-domain data set as it contains ratings on items from a vast array of categories. Evaluation shows that cross-domain prediction is possible.
Indexing land surface for efficient kNN query
Authors: Cyrus Shahabi, Lu-An Tang, Songhua Xing
Venue: Proceedings of the VLDB Endowment (2008)

The class of k Nearest Neighbor (kNN) queries is frequently used in geospatial applications. Many studies focus on processing kNN in Euclidean and road network spaces. Meanwhile, with the recent advances in remote sensory devices that can acquire detailed elevation data, the new geospatial applications heavily operate on this third dimension, i.e., land surface. Hence, for the field of databases to stay relevant, it should be able to efficiently process spatial queries given this constrained third dimension. However, online processing of the surface k Nearest Neighbor (skNN) queries is quite challenging due to the huge size of land surface models which renders any accurate distance computation on the surface extremely slow. In this paper, for the first time, we propose an index structure on land surface that enables exact and fast responses to skNN queries. Two complementary indexing schemes, namely Tight Surface Index (TSI) and Loose Surface Index (LSI), are constructed and stored collectively on a single novel data structure called Surface Index R-tree (SIR-tree). With those indexes, we can process skNN query efficiently by localizing the search and minimizing the invocation of the costly surface distance computation and hence incurring low I/O and computation costs. Our algorithm does not need to know the value of k a priori and can incrementally expand the search region using SIR-tree and report the query result progressively. It also reports the exact shortest surface paths to the query results. We show through experiments with real world data sets that our algorithm has better performance than the competitors in both efficiency and accuracy.
An ANP-based technology network for identification of core technologies: A case of telecommunication technologies
Authors: Hakyeon Lee, Chulhyun Kim, Hyunmyung Cho, Yongtae Park
Venue: Expert Systems with Applications: An International Journal (2009)

There have often been attempts to examine technological structure and linkage as a network. Network analysis has been mainly employed with various centrality measures to identify core technologies in a technology network. None of the existing centrality measures, however, can successfully capture indirect relationships in a network. To address this limitation, this study proposes a novel approach based on the analytic network process (ANP) to identification of core technologies in a technology network. Since the ANP is capable of measuring the relative importance that captures all the indirect interactions in a network, the derived ''limit centrality'' indicates the importance of a technology in terms of impacts on other technologies, taking all the direct and indirect influences into account. The proposed approach is expected to allow technology planners to understand current technological trends and advances by identifying core technologies based on limit centralities. Using patent citation data as proxy for interactions between technologies, a case study on telecommunication technologies is presented to illustrate the proposed approach.