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1.
A well-known challenge for multi-document summarization (MDS) is that a single best or “gold standard” summary does not exist, i.e. it is often difficult to secure a consensus among reference summaries written by different authors. It therefore motivates us to study what the “important information” is in multiple input documents that will guide different authors in writing a summary. In this paper, we propose the notions of macro- and micro-level information. Macro-level information refers to the salient topics shared among different input documents, while micro-level information consists of different sentences that act as elaborating or provide complementary details for those salient topics. Experimental studies were conducted to examine the influence of macro- and micro-level information on summarization and its evaluation. Results showed that human subjects highly relied on macro-level information when writing a summary. The length allowed for summaries is the leading factor that affects the summary agreement. Meanwhile, our summarization evaluation approach based on the proposed macro- and micro-structure information also suggested that micro-level information offered complementary details for macro-level information. We believe that both levels of information form the “important information” which affects the modeling and evaluation of automatic summarization systems. 相似文献
2.
《Electronic Journal of Biotechnology》2014,17(3):122-125
BackgroundA biosurfactant produced by Pseudomonas aeruginosa cultivated in a low-cost medium formulated with 2.5% vegetable oil refinery residue and 2.5% corn steep liquor and distilled water was employed to stabilize silver nanoparticles in the liquid phase. The particles were initially synthesized using NaBH4 as reducing agent in biosurfactant reverse micelles and were extracted from the micellar solution to disperse in heptane.ResultsA silver particle size in the range of 1.13 nm was observed. The UV–vis absorption spectra proposed that silver nanoparticles could be formed in the reverse micelles and relatively stabilized for at least 3 months without passivator addition. The Transmission Electron Microscope (TEM) shows that the silver nanoparticles are of spherical form and relatively uniform.ConclusionsThis process provided a simpler route for nanoparticle synthesis compared to existing systems using whole organisms or partially purified biological extracts, showing that the low-cost biosurfactant can be used for nanoparticle synthesis as a non-toxic and biodegradable stabilizing agent. 相似文献
3.
Krzysztof Szalewicz 《Journal of The Franklin Institute》2010,347(4):698-707
At very low temperatures, helium becomes superfluid, with properties significantly different from those of familiar substances. Although superfluid helium has been the subject of extensive investigations, until recently no practical applications have been found that would utilize its unusual properties. The main reason was that macroscopic samples of superfluid helium expel all other atoms or molecules. Only in the 1990s, Scoles and collaborators demonstrated that one can embed “impurities”, atoms and molecules, in low-temperature helium if it is in the form of small droplets. Such droplets contain only a few thousands atoms and therefore are called “nanodroplets”. Furthermore, Scoles and coworkers were able to measure spectra of the impurities. Subsequently, Toennies and collaborators have found that the spectral lines are very sharp, almost as sharp as in the gas phase, and demonstrated that this sharpness has to be due to the superfluidity of helium in the nanodroplets. The newly created technique of helium-nanodroplet spectroscopy allowed investigations of molecules or clusters that are unstable in gas phase and has significantly increased our understanding of superfluid helium at microscopic level. 相似文献
4.
Masahiro Niitsuma Masaki Matsubara Masaki Oono Hiroaki Saito 《Information processing & management》2011
The purpose of this study is to develop an automatic basso continuo playing system. In order to find a musically appropriate sequence of chords, we propose the principle of “harmony cost”, which is defined as the sum of two different costs: one is the “local cost” which indicates the unlikelihood of a certain chord allocation and the other is the “transition cost”, which indicates the unlikelihood of a certain connection between two chords. Automatic basso continuo playing is realised by searching for the optimal chord sequence, which minimises the accumulated harmony cost. The proposed method is evaluated by three experiments. Each experiment verifies the effectiveness of the proposed method. 相似文献
5.
This study uses bibliometric analysis and citation context analysis to identify the influence of the main concepts embedded in Taylor’s 1968 classic article entitled Question-Negotiation and Information-Seeking in Libraries. This study analyses articles published between 1969 and 2010 which cite Taylor’s article. The results show that Taylor’s article on a question-negotiation model is increasingly visible and its influence is not limited to the discipline of library and information science. Of the 14 cited concepts identified, the concept of “four levels of information needs” was cited most (31.7%), followed by “question negotiation” (20.5%) and “other concepts relating to information needs” (17.9%). The results indicate an increasing trend in the citations of “four levels of information needs” and this concept also received the most attention from information retrieval research. A decreasing trend was evident for the concept of “question negotiation” and this concept was frequently cited by reference service researchers. In addition, among the 10 citation functions, “related literature” was dominant (30.8%). Both “evidence” and “views” were in second place with the same percentage (18.7%), followed by “terms” (9.2%) and “background information” (7.2%). A decreasing trend was identified in the top three citation functions, whereas an increasing trend was observed in the “term” and “background information” functions. 相似文献
6.
Despite a number of studies looking at Web experience and Web searching tactics and behaviours, the specific relationships between experience and cognitive search strategies have not been widely researched. This study investigates how the cognitive search strategies of 80 participants might vary with Web experience as they engaged in two researcher-defined tasks and two participant-defined information seeking tasks. Each of the two researcher-defined tasks and participant-defined tasks included a directed search task and a general-purpose browsing task. While there were almost no significant performance differences between experience levels on any of the four tasks, there were significant differences in the use of cognitive search strategies. Participants with higher levels of Web experience were more likely to use “Parallel player”, “Parallel hub-and-spoke”, “Known address search domain” and “Known address” strategies, whereas participants with lower levels of Web experience were more likely to use “Virtual tourist”, “Link-dependent”, “To-the-point”, “Sequential player”, “Search engine narrowing”, and “Broad first” strategies. The patterns of use and differences between researcher-defined and participant-defined tasks and between directed search tasks and general-purpose browsing tasks are also discussed, although the distribution of search strategies by Web experience were not statistically significant for each individual task. 相似文献
7.
A user study of aNobii was conducted with an aim to exploring possible criteria for evaluating social navigational tools. A set of measures designed to capture various aspects of the benefits provided by the tools was proposed. To test the applicability of these measures, a within-subject experimental design was adopted where fifty regular aNobii users searched alternately with three book-finding tools: browsing “friends’ bookshelves”, “similar bookshelves”, and “books by known authors”. Other than the self-report user experience and search result measures, the “choice set” model was used as a novel framework for navigational effectiveness. Further analyses were conducted to explore whether three aspects of reader preference, “preference insight”, “preference diversity”, and “reading involvement” might influence the performance of the tools. 相似文献
8.
Sustainability oriented innovation and technology studies have received increasing attention over the past 10-15 years. In particular, a new field dealing with “sustainability transitions” has gained ground and reached an output of 60-100 academic papers per year. In this article, we aim to identify the intellectual contours of this emerging field by conducting a review of basic conceptual frameworks, together with bibliographical analysis of 540 journal articles in the field. It is against this background that we position the six papers assembled in a special section in Research Policy. These papers pave the way for new conceptual developments and serve as stepping-stones in the maturation of sustainability transition studies, by linking with the scholarly literatures of management studies, sociology, policy studies, economic geography, and modeling. 相似文献
9.
This study examines how libraries within college and university settings in the United States have dealt with the influx of patron mobile telephone use. We contacted 150 colleges and universities throughout the United States and received 87 responses. These institutions were ranked by US News and World Report in their 2006 Edition of “America’s Best Colleges;” we sampled from their list stratified within the following categories: “top public universities;” “best liberal arts colleges;” “fourth tier liberal arts colleges;” “best national universities;” and “fourth tier national universities.” We found that those college and university libraries adopt an array of stances when approaching cell phone use within their library facilities. These approaches include structured guidelines that specifically address cell phone use posted on the library website, signs displayed throughout the library barring cell phone use, and signage that provides patrons with a list of areas in which use is permitted. Interestingly, we found that several libraries lack any kind of mobile phone policy and instead, assume all patrons will behave in a proper way. 相似文献
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Roger A. Grey Author Vitae 《Journal of The Franklin Institute》2004,341(3):197-205
Throughout his distinguished career of over 40 years, Robin Hochstrasser has made significant contributions to several areas of science in the fields of chemical and biochemical physics. He has been at the forefront and made fundamental contributions to the fields of photochemistry, solid-state chemistry, ultra-fast laser spectroscopies, and protein dynamics. He has been a prolific researcher, producing over 560 publications. His work has been characterized by experts in the fields as “a constant stream of experiments of lasting significance” (J. Phys. Chem. 100 (1996) 11791).Robin began his career in the 1960s using a variety of magnetic and electric field measurements to study crystals at low temperatures to understand spin quantization in solids and electron exchanged-mediated energy transfer. This work, described as a “classic contribution” (J. Phys. Chem. 100 (1996) 11791) was the basis for much of the subsequent experimental and theoretical work on the effect of magnetic fields on molecular spectra and on the measurements of dipole moments.In the late 1970s, Robin recognized the power of laser technology for the study of molecules and soon became a leader in the field investigating solid, gas phase, and condensed phase systems. He developed and applied various ultra-fast laser techniques to study the structure and dynamics of complex molecules in liquid phase, chemical, and biochemical reactions. He made seminal contributions to the development of two-dimensional infrared spectroscopy (2D IR) on a time scale of a picosecond or less. This 2D IR spectroscopy measures coupling between two functional groups in a large molecule and can thus be used to measure distances, as for example, two amide carbonyl groups in a peptide molecule. On the ultra-fast timescale, one application of 2D IR is to gain information on the rate of protein folding and unfolding in solution. Some of Robin's greatest contributions to understanding biomolecules are said to be in the experimental studies on the picosecond and femtosecond dynamics of heme proteins. Using techniques he developed he was able to observe the interactions of oxygen, carbon monoxide, and nitric oxide with hemoglobin inside the protein. 相似文献
12.
This paper focuses on the role of capabilities in economic development. In recent years, the quality and availability of data on different aspects of development have improved, and this provides new opportunities for investigating the reasons behind the large differences in economic development. Using factor analysis on data for 25 indicators and 115 countries between 1992 and 2004, we identify four different types of “capabilities”: the development of the “innovation system”, the quality of “governance”, the character of the “political system” and the degree of “openness” of the economy. Innovation systems and governance are shown to be of particular importance for economic development. 相似文献
13.
Crowd science: The organization of scientific research in open collaborative projects 总被引：1，自引：0，他引：1
A growing amount of scientific research is done in an open collaborative fashion, in projects sometimes referred to as “crowd science”, “citizen science”, or “networked science”. This paper seeks to gain a more systematic understanding of crowd science and to provide scholars with a conceptual framework and an agenda for future research. First, we briefly present three case examples that span different fields of science and illustrate the heterogeneity concerning what crowd science projects do and how they are organized. Second, we identify two fundamental elements that characterize crowd science projects – open participation and open sharing of intermediate inputs – and distinguish crowd science from other knowledge production regimes such as innovation contests or traditional “Mertonian” science. Third, we explore potential knowledge-related and motivational benefits that crowd science offers over alternative organizational modes, and potential challenges it is likely to face. Drawing on prior research on the organization of problem solving, we also consider for what kinds of tasks particular benefits or challenges are likely to be most pronounced. We conclude by outlining an agenda for future research and by discussing implications for funding agencies and policy makers. 相似文献
14.
Thomas K. Gaisser 《Journal of The Franklin Institute》2011,348(3):453-458
This award recognizes two specific discoveries that constitute the experimental discovery of neutrino oscillations. In 1998 the Super-Kamiokande group under the leadership of Yoji Totsuka published their paper, “Evidence for Oscillation of Atmospheric Neutrinos” in Physical Review Letters [1]. The paper describes a deficit of muon-type neutrinos from below the detector relative to those from above. It explains this “atmospheric neutrino anomaly” as a result of transformation of some of the muon neutrinos into another type of neutrino. Four years later, the group led by Arthur McDonald described “Direct Evidence for Neutrino Flavor Transformation from Neutral-Current Interactions in the Sudbury Neutrino Observatory” [2] in the same journal. This experiment detected lower energy neutrinos from deep inside the Sun. By measuring all flavors of neutrinos with large rates, the SNO collaboration showed definitively that the long-standing “solar neutrino puzzle” was another manifestation of neutrino oscillations. As a result of these two experiments, we now understand that neutrinos can change identities during propagation and that both the solar and atmospheric neutrino “problems” result from the same underlying phenomenon of oscillations. A consequence of neutrino oscillations is that neutrinos, previously thought to be massless, must have a non-zero rest mass. 相似文献
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16.
Jadranka Švarc 《Research Policy》2006,35(1):144-159
This paper discusses the roles of socio-political factors and related public policies in the economic growth of Croatia, as well as their influence on its transition to a knowledge economy (KE). The Croatian experience might help to understand transition processes in other Central and Eastern European Countries (CEECs). This paper argues that Croatia has failed to capitalize on its inherited science base, which could have been used as a starting point in the transition towards a KE, because it has not made the shift from an obsolete socialist-style science policy to a modern innovation policy (IP); the latter is seen as the new policy paradigm necessary for structural adjustment to a KE.Covert socio-political growth factors shaped by the country-specific historical heritage of Croatia have prevented the recognition of the need for structural adjustment to the new technology regime, and have led to the belief that the IP is not only irrelevant but is also a relict of the state interventionism inherited from socialism, which was the most serious obstacle to policy reform.Examples drawn from the development of the IP and the National System of Innovation (NSI) in Croatia, which shares the socialist model of science policy and the socio-political context of the transition towards a market economy with other CEECs, can help to explain the failure of the IP. In the Croatian case, the decisive factors were the social state of so-called “semi-modernism” and the governance of the so-called “de-industrializing elite”.This paper concludes that the transition of a CEEC from a market economy to a KE requires a serious re-design of development policy, the effectiveness of which depends on social change determined by the political recognition and social assimilation of the new technological regime. In this sense, the current paper contributes to the understanding of the roles of social capital and governance in the economic growth of post-socialist countries. 相似文献
17.
Ghaleb A. Husseini Mario A. Diaz de la Rosa Saif Al Mamary Abdullah Al Baik 《Journal of The Franklin Institute》2011,348(1):125-133
Ultrasound is being investigated as a trigger mechanism to deliver high concentrations of chemotherapy drugs to cancerous tissues using polymeric micelles. In this paper, we examined the kinetics of acoustic release of doxorubicin using stabilized and non-stabilized micelles. Kinetic models were used to regress release and re-encapsulation time constants for three different compounds, namely non-stabilized Pluronic® P105 micelles, P105 micelles stabilized using an interpenetrating network of N,N-diethylacrylamide and micelles formed by PEO-b-poly(NIPAAm-co-HEMA-lactaten). Results showed that the kinetic release constant (kr) depends on the micellar system under investigation. On the other hand, there is no statistically significant difference between re-encapsulation rate constants for stabilized and unstabilized micelles. We hypothesize that kr depends on the degree of cross-linking or stabilization. 相似文献
18.
The second French Community Innovation Survey (CIS) indicates that 14% of R&D collaborating firms had to abandon or delay their innovation projects due to difficulties in their partnerships, an outcome which we term “cooperation failures”. Controlling for sample selection on the cooperation decision, our estimates show that firms collaborating with competitors and public research organizations (PROs), especially when they are foreign, are more likely to delay or stop an innovation project because of difficulties encountered in their R&D partnerships. More surprisingly, firms collaborating with their suppliers also face a higher risk of “cooperation failures”. At least for PROs, firms can reduce the risk of “cooperation failures” through previous experiences in partnerships. Larger firms and group subsidiaries are less likely to face “cooperation failures”, and so do firms in industries with a strong appropriability regime. 相似文献
19.
Despite the common public use of Web search engines, their internal design details mostly remain as a black art. The speculation is that there is a significant knowledge gap between what is published by academia and what is guarded behind the doors of large-scale search companies. “Search Engines: Information Retrieval in Practice” is one of the few books that make an attempt to cover issues involved in search engine design and is probably the most comprehensive book published so far on this topic. Unfortunately, the book fails to be a complete search engine guide as its content is dominated by the topics from information retrieval, text processing, and statistics. More precisely, the focus of the book is biased towards the “search” rather than the “engines” as, in most places, discussions on effectiveness dominate those on efficiency by a great margin. However, the book stands as a very solid IR book. 相似文献
20.
This article aimed to identify the effect of university-industry (U-I) collaborations on the innovative performance of firms operating in the advanced materials field, and by doing so, it proposed an original classification of the research organization partners. The main contribution resides in the estimation of the role played by collaborations with differently experienced scientists. In contrast with previous studies, whose empirical setting was the life science industry, in the advanced materials industry the most effective collaborations are not with “Star scientists”, but with “Pasteur scientists”. The latter concept was empirically tested first by the authors of this article, to deepen the present understanding of industrial heterogeneity in innovation processes and to offer new insights for the formulation of corporate innovation strategies. The results of the estimation of a negative binomial regression model applied to a sample of 455 firms active in the photocatalysis in Japan confirm the idea that engaging in research collaborations, measured as co-invention, with “Pasteur scientists” increases firms’ R&D productivity, measured as number of registered patents. In contrast, we found that firms’ collaborations with “Star scientists” exert little impact on their innovative output. 相似文献