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Finding Similar/Diverse Solutions in Answer Set Programming  [PDF]
Thomas Eiter,Esra Erdem,Halit Erdogan,Michael Fink
Computer Science , 2011, DOI: 10.1017/S1471068411000548
Abstract: For some computational problems (e.g., product configuration, planning, diagnosis, query answering, phylogeny reconstruction) computing a set of similar/diverse solutions may be desirable for better decision-making. With this motivation, we studied several decision/optimization versions of this problem in the context of Answer Set Programming (ASP), analyzed their computational complexity, and introduced offline/online methods to compute similar/diverse solutions of such computational problems with respect to a given distance function. All these methods rely on the idea of computing solutions to a problem by means of finding the answer sets for an ASP program that describes the problem. The offline methods compute all solutions in advance using the ASP formulation of the problem with an ASP solver, like Clasp, and then identify similar/diverse solutions using clustering methods. The online methods compute similar/diverse solutions following one of the three approaches: by reformulating the ASP representation of the problem to compute similar/diverse solutions at once using an ASP solver; by computing similar/diverse solutions iteratively (one after other) using an ASP solver; by modifying the search algorithm of an ASP solver to compute similar/diverse solutions incrementally. We modified Clasp to implement the last online method and called it Clasp-NK. In the first two online methods, the given distance function is represented in ASP; in the last one it is implemented in C++. We showed the applicability and the effectiveness of these methods on reconstruction of similar/diverse phylogenies for Indo-European languages, and on several planning problems in Blocks World. We observed that in terms of computational efficiency the last online method outperforms the others; also it allows us to compute similar/diverse solutions when the distance function cannot be represented in ASP.
Reducing Fuzzy Answer Set Programming to Model Finding in Fuzzy Logics  [PDF]
Jeroen Janssen,Steven Schockaert,Dirk Vermeir,Martine De Cock
Computer Science , 2011,
Abstract: In recent years answer set programming has been extended to deal with multi-valued predicates. The resulting formalisms allows for the modeling of continuous problems as elegantly as ASP allows for the modeling of discrete problems, by combining the stable model semantics underlying ASP with fuzzy logics. However, contrary to the case of classical ASP where many efficient solvers have been constructed, to date there is no efficient fuzzy answer set programming solver. A well-known technique for classical ASP consists of translating an ASP program $P$ to a propositional theory whose models exactly correspond to the answer sets of $P$. In this paper, we show how this idea can be extended to fuzzy ASP, paving the way to implement efficient fuzzy ASP solvers that can take advantage of existing fuzzy logic reasoners. To appear in Theory and Practice of Logic Programming (TPLP).
A Topic Clustering Approach to Finding Similar Questions from Large Question and Answer Archives  [PDF]
Wei-Nan Zhang, Ting Liu, Yang Yang, Liujuan Cao, Yu Zhang, Rongrong Ji
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0071511
Abstract: With the blooming of Web 2.0, Community Question Answering (CQA) services such as Yahoo! Answers (http://answers.yahoo.com), WikiAnswer (http://wiki.answers.com), and Baidu Zhidao (http://zhidao.baidu.com), etc., have emerged as alternatives for knowledge and information acquisition. Over time, a large number of question and answer (Q&A) pairs with high quality devoted by human intelligence have been accumulated as a comprehensive knowledge base. Unlike the search engines, which return long lists of results, searching in the CQA services can obtain the correct answers to the question queries by automatically finding similar questions that have already been answered by other users. Hence, it greatly improves the efficiency of the online information retrieval. However, given a question query, finding the similar and well-answered questions is a non-trivial task. The main challenge is the word mismatch between question query (query) and candidate question for retrieval (question). To investigate this problem, in this study, we capture the word semantic similarity between query and question by introducing the topic modeling approach. We then propose an unsupervised machine-learning approach to finding similar questions on CQA Q&A archives. The experimental results show that our proposed approach significantly outperforms the state-of-the-art methods.
Reduction in host-finding behaviour in fungus-infected mosquitoes is correlated with reduction in olfactory receptor neuron responsiveness
Justin George, Simon Blanford, Michael J Domingue, Matthew B Thomas, Andrew F Read, Thomas C Baker
Malaria Journal , 2011, DOI: 10.1186/1475-2875-10-219
Abstract: Anopheles stephensi mosquitoes were exposed to Beauveria bassiana or Metarhizium acridum fungal spores and sub-lethal effects of exposure to fungal infection were studied, especially the potential for reductions in feeding and host location behaviours related to olfaction. Electrophysiological techniques, such as electroantennogram, electropalpogram and single sensillum recording techniques were then employed to investigate how fungal exposure affected the olfactory responses in mosquitoes.Exposure to B. bassiana caused significant mortality and reduced the propensity of mosquitoes to respond and fly to a feeding stimulus. Exposure to M. acridum spores induced a similar decline in feeding propensity, albeit more slowly than B. bassiana exposure. Reduced host-seeking responses following fungal exposure corresponded to reduced olfactory neuron responsiveness in both antennal electroantennogram and maxillary palp electropalpogram recordings. Single cell recordings from neurons on the palps confirmed that fungal-exposed behavioural non-responders exhibited significantly impaired responsiveness of neurons tuned specifically to 1-octen-3-ol and to a lesser degree, to CO2.Fungal infection reduces the responsiveness of mosquitoes to host odour cues, both behaviourally and neuronally. These pre-lethal effects are likely to synergize with fungal-induced mortality to further reduce the capacity of mosquito populations exposed to fungal biopesticides to transmit malaria.Chemical insecticides targeting adult female mosquito vectors have been one of the most successful strategies employed for malaria control [1]. However, the effectiveness and sustainability of insecticide-based interventions, such as indoor residual sprays (IRS) and insecticide-treated nets (ITNs), is being undermined by evolution of insecticide resistance [1-8]. Accordingly, there is now a pressing need for novel control tools including alternative, non-chemical approaches [8]. One promising alternative is fung
Pinaki Mitra,Girish Sundaram,Senthil Kumar G,Vishal Kurup
International Journal of Electronic Commerce Studies , 2010,
Abstract: A mashup gathers useful information from various sources and presents it in a meaningful way. The IBM Mashup Center is one of the most widely used mashup editors. Data comes from different sources in various formats and the mashup editor combines them together and givesthe output in a different format. The IBM Mashup Center currently supports feed generation from various sources like Excel files, Access files, database files, CSV files, etc. Currently, however, it does not support feed generation from a mail server. Thus, we have implemented a mail plugin that adds this feature to the mashup center. The mail plugin fetches the mail using the POP3/IMAP protocol and converts it into ATOM feeds. The mail plugin uses a Java mail API for connecting to and accessing the mail server. The generated feed gets a unique URL which can be used by widgets to access the feed. It supports the dynamic addition of new mail servers to its trust store. Security is further enhanced by providing a digital signature feature that is in enveloped form, i.e. it goes with the feed as one of its elements. The digital signature is checked at the receiver side to assure data integrity.
Transgenic Mosquitoes Expressing a Phospholipase A2 Gene Have a Fitness Advantage When Fed Plasmodium falciparum-Infected Blood  [PDF]
Ryan C. Smith, Christopher Kizito, Jason L. Rasgon, Marcelo Jacobs-Lorena
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0076097
Abstract: Background Genetically modified mosquitoes have been proposed as an alternative strategy to reduce the heavy burden of malaria. In recent years, several proof-of-principle experiments have been performed that validate the idea that mosquitoes can be genetically modified to become refractory to malaria parasite development. Results We have created two transgenic lines of Anopheles stephensi, a natural vector of Plasmodium falciparum, which constitutively secrete a catalytically inactive phospholipase A2 (mPLA2) into the midgut lumen to interfere with Plasmodium ookinete invasion. Our experiments show that both transgenic lines expressing mPLA2 significantly impair the development of rodent malaria parasites, but only one line impairs the development of human malaria parasites. In addition, when fed on malaria-infected blood, mosquitoes from both transgenic lines are more fecund than non-transgenic mosquitoes. Consistent with these observations, cage experiments with mixed populations of transgenic and non-transgenic mosquitoes show that the percentage of transgenic mosquitoes increases when maintained on Plasmodium-infected blood. Conclusions Our results suggest that the expression of an anti-Plasmodium effector gene gives transgenic mosquitoes a fitness advantage when fed malaria-infected blood. These findings have important implications for future applications of transgenic mosquito technology in malaria control.
A Study on LOCKSS Plugin Technology and Implementation in Chinese E-Journals

Li Chunwang,

现代图书情报技术 , 2006,
Abstract: After introducing the architecture and the long-term preservation policy of LOCKSS, this paper analyzes methods, attributes, types and developoment modes of plugin, and discusses the implementation of Chinese e-journals plugin for LOCKSS.
OpenBook WordPress Plugin: Open Source Access to Bibliographic Data  [cached]
John Miedema
Code4Lib Journal , 2008,
Abstract: OpenBook is a WordPress PHP plugin that implements the Open Library APIs to insert book covers, titles, authors and publishers into web pages. The motive behind the development was to provide an easy alternative to the common practice of linking to Amazon. Open Library was selected as a data source because it is both open source and open data.The plugin is useful for book reviewers, library webmasters, anyone who wants to put book covers and data on their WordPress blog or website. The plugin also allows users to add links to publisher websites, a feature that was considered significant to independent publishers.
Doppler Boosting May Have Played No Significant Role in the Finding Surveys of Radio-Loud Quasars  [PDF]
Morley B. Bell
International Journal of Astronomy and Astrophysics (IJAA) , 2012, DOI: 10.4236/ijaa.2012.21008
Abstract: There appears to be a fundamental problem facing Active Galactic Nuclei (AGN) jet models that require highly relativistic ejection speeds and small jet viewing angles to explain the large apparent superluminal motions seen in so many of the radio-loud quasars with high redshift. When the data are looked at closely it is found that, assuming the core component is unboosted, only a small percentage of the observed radio frequency flux density from these sources can be Doppler boosted. If the core component is boosted the percentage of boosted to unboosted flux will be higher but will still be far from the 90 percent required for Doppler boosting to have played a significant role. Without a highly directed, Doppler boosted component that dominates the observed flux, radio sources found in low-frequency finding surveys cannot be preferentially selected with small jet viewing angles. The distribution of jet orientations will then follow the sini curve associated with a random distribution, where only a very few sources (~1%) will have the small viewing angles (<8°) required to explain apparent superluminal motions vapp > 10c, and this makes it difficult to explain how around 33% of the radio-loud AGNs with high redshift can exhibit such highly superluminal motions. When the boosted component is the dominant one it can be argued that in a flux limited sample only those members with small viewing angles would be picked up while those with larger viewing angles (the un-boosted ones) would be missed. However, this is not the case when the boosted component is small and a new model to explain the high apparent superluminal motions may be needed if the redshifts of high-redshift quasars are to remain entirely cosmological.
CytoITMprobe: a network information flow plugin for Cytoscape  [PDF]
Aleksandar Stojmirovi?,Alexander Bliskovsky,Yi-Kuo Yu
Computer Science , 2011,
Abstract: To provide the Cytoscape users the possibility of integrating ITM Probe into their workflows, we developed CytoITMprobe, a new Cytoscape plugin. CytoITMprobe maintains all the desirable features of ITM Probe and adds additional flexibility not achievable through its web service version. It provides access to ITM Probe either through a web server or locally. The input, consisting of a Cytoscape network, together with the desired origins and/or destinations of information and a dissipation coefficient, is specified through a query form. The results are shown as a subnetwork of significant nodes and several summary tables. Users can control the composition and appearance of the subnetwork and interchange their ITM Probe results with other software tools through tab-delimited files. The main strength of CytoITMprobe is its flexibility. It allows the user to specify as input any Cytoscape network, rather than being restricted to the pre-compiled protein-protein interaction networks available through the ITM Probe web service. Users may supply their own edge weights and directionalities. Consequently, as opposed to ITM Probe web service, CytoITMprobe can be applied to many other domains of network-based research beyond protein-networks. It also enables seamless integration of ITM Probe results with other Cytoscape plugins having complementary functionality for data analysis.
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