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161.
Previous research has found that researchers rank journal reputation and impact factor (IF) amongst the key selection criteria when choosing where to submit. We explored the actual effect upon submission numbers of several possible factors. We retrieved 10 years of submission data from over a thousand journals, as well as data on IF, retractions, and other factors. We performed statistical analysis and identified correlations. We also undertook case study research on the 55 most significant submission decreases. We found a statistically significant correlation between changes in IF, ISI percentage ranking, and changes in submissions numbers in subsequent years. We also found a statistically significant effect on submission numbers in the year following the publication of a retraction. Our case studies identified other factors, including negative feedback on the peer review process. Our findings regarding IF confirm previous indications about the significance of IF on submissions. We explain the correlation with retractions through the concept of ‘peer review reputation’. These results indicate that editors and publishers need to focus on a journal's peer review practices, as well as a journal's IF, if they are to maintain and grow submissions.  相似文献   
162.
Text document clustering provides an effective and intuitive navigation mechanism to organize a large amount of retrieval results by grouping documents in a small number of meaningful classes. Many well-known methods of text clustering make use of a long list of words as vector space which is often unsatisfactory for a couple of reasons: first, it keeps the dimensionality of the data very high, and second, it ignores important relationships between terms like synonyms or antonyms. Our unsupervised method solves both problems by using ANNIE and WordNet lexical categories and WordNet ontology in order to create a well structured document vector space whose low dimensionality allows common clustering algorithms to perform well. For the clustering step we have chosen the bisecting k-means and the Multipole tree, a modified version of the Antipole tree data structure for, respectively, their accuracy and speed.
Diego Reforgiato RecuperoEmail:
  相似文献   
163.
Intelligent use of the many diverse forms of data available on the Internet requires new tools for managing and manipulating heterogeneous forms of information. This paper uses WHIRL, an extension of relational databases that can manipulate textual data using statistical similarity measures developed by the information retrieval community. We show that although WHIRL is designed for more general similarity-based reasoning tasks, it is competitive with mature systems designed explicitly for inductive classification. In particular, WHIRL is well suited for combining different sources of knowledge in the classification process. We show on a diverse set of tasks that the use of appropriate sets of unlabeled background knowledge often decreases error rates, particularly if the number of examples or the size of the strings in the training set is small. This is especially useful when labeling text is a labor-intensive job and when there is a large amount of information available about a particular problem on the World Wide Web.
Haym HirshEmail:
  相似文献   
164.
Previous papers on grey literature by the authors have described (1) the need for formal metadata to allow machine understanding and therefore scalable operations; (2) the enhancement of repositories of grey (and other) e-publications by linking with CRIS (Current Research Information Systems); (3) the use of the research process to collect metadata incrementally reducing the threshold barrier for end-users and improving quality in an ambient GRIDs environment. This paper takes the development one step further and proposes “intelligent” grey objects. The hypothesis is in 2 parts: (1) that the use of passive catalogs of metadata does not scale (a) in a highly distributed environment with millions of nodes and (b) with vastly increased volumes of R&D output grey publications with associated metadata; (2) that a new paradigm is required that (a) integrates grey with white literature and other R&D outputs such as software, data, products and patents (b) in a self-managing, self-optimizing way and that this paradigm manages automatically curation, provenance digital rights, trust, security and privacy. Concerning (1) existing repositories provide catalogs; harvesting takes increasing time ensuring non-currency. The end-user expends much manual effort/intelligence to utilize the results. The elapsed time of (1) the network (2) the centralized (or centrally controlled distributed) catalog server searches (3) end-user intervention becomes unacceptable. Concerning (2) there is no paradigm currently known to the authors that satisfies the requirement. Our proposal is outlined below. Hyperactive combines both hyperlinking and active properties of a (grey) object. Hyperlinking implies multimedia components linked to form the object and also external links to other resources. The term active implies that objects do not lie passively in a repository to be retrieved by end-users. They “get a life” and the object moves through the network knowing where it is going. A hyperactive grey object is wrapped by its (incrementally recorded) formal metadata and an associated (software) agent. It moves through process steps such as initial concept, authoring, reviewing and depositing in a repository. The workflow is based on the rules and information in the corporate data repository with which the agent interacts. Once the object is deposited, the agent associated with it actively pushes the object to the end-users (or systems) whose metadata indicate interest or an obligation in a workflowed process. The agents check the object and user (or system) metadata for rights, privacy, security parameters, and for any charges and assure compatibility. Alternatively the object can be found passively by end-user or system agents. The object can also associate itself with other objects forming relationships utilising metadata or content. Declared relationships include references and citations; workflowed relationships include versions and also links to corporate information and research datasets and software; inferenced relationships are discovered relationships such as between documents by different authors developed from an earlier idea of a third author. Components of this paradigm have been implemented to some extent. The challenge is implementing—respecting part two of the hypothesis—the integration architecture. This surely is harnessing the power of grey.
Anne AssersonEmail:
  相似文献   
165.
The emergence of the new format of electronic/digital records provides the opportunity for archivists to reconsider the presumed format-neutrality of professional practice. As research in electronic records has served to re-emphasise, without an understanding of the needs and forms of material, then the work of archivists can have a profound impact on the evidential value and long-term research potential of the material. This paper attempts to broaden the debate about the requirements of all archival formats, and to build a new regime of 21st-century format specialists.
Joanna SassoonEmail:

Dr. Joanna Sassoon    is currently seconded to Edith Cowan University as Senior Lecturer in the School of Computer and Information Science. Her permanent position is in the State Records Office of Western Australia. She has long experience in managing archival collections, and has written extensively on a range of topics including digitisation, the effect of institutional practice on archival materials, environmental and indigenous history, and photographs as archives, and her work has been recognised with two Mander-Jones awards from the Australian Society of Archivists. She holds a Ph.D. in history with distinction from the University of Western Australia.  相似文献   
166.
In two experiments, participants inspected and drank a series of drinks, half of which contained sugar and half unpalatable Tween20 (tween). Each sugar and tween drink had a particular flavor and color. Following this training, the flavors of the sugar drinks were assigned higher hedonic evaluations than were those of the tween drinks, even though the participants did not reliably report which flavors had been present in the sugar and tween drinks during training. Moreover, the evaluative conditioning of the flavors was unaffected by whether or not the colors alone had been pretrained to predict the presence of sugar or tween in the drinks. In accord with Baeyens, Eelen, van den Bergh, and Crombez (1990), we conclude that flavor-evaluative conditioning is not mediated by contingency learning.  相似文献   
167.
As institutions of Higher Education try to balance limited resources with the rising costs of technology, some institutions are turning to Open Source software for campus-wide applications such as course management systems and portals. The assumption is that Open Source will provide the flexibility to build pedagogically sound learning environments while increasing technology efficiencies. This paper outlines the current state of Open Source software deployment in US Higher Education based on a survey of 772 Chief Academic Officers and Chief Information Officers conducted in 2006. The results indicate that Carnegie classification is a critical differentiator of awareness, adoption, and perceptions of Open Source software applications, with perceived cost of ownership being the key driver of Open Source adoption. Moreover, the study shows that institutions have made little progress in the development of polices and procedures for Open Source regulatory compliance and security. The study serves as a baseline for future research into the conditions for successful use of Open Source for supporting integrated learning environments that deliver campus-wide efficiencies.
Shahron Williams van RooijEmail:

Shahron Williams van Rooij   is Assistant Professor of Instructional Technology at George Mason University with a focus on the university’s e-Learning Certificate Program. She holds a Ph.D. in Quantitative Methods in the Social Sciences from the City University of New York and has just completed a second doctorate in Instructional Technology and Software Information Systems at George Mason University. As a Certified Distance Education Professional (C.D.E.P.) credentialed by Texas A&M University, she is a frequent speaker on the development of Web-based education and has published in a variety of journals such as the WebNet Journal, the Journal of Interactive Learning Research, the Journal of Modern Business, the Marketing Research Review and the Journal of Research on Technology in Education. Prior to joining GMU, she was the Director of Marketing at Datatel, Inc., in Fairfax, VA, where she facilitated the engineering of new e-learning technology solutions.  相似文献   
168.
Brix weight per stool (BW) of sugarcane is a complex trait, which is the final product of a combination of many components. Diallel cross experiments were conducted during a period of two years for BW and its five component traits, including stalk diameter (SD), stalk length (SL), stalk number (SN), stalk weight (SW), and brix scale (BS) of sugarcane. Phenotypic data of all the six traits were analyzed by mixed linear model and their phenotype variances were portioned into additive (A),dominance (D), additive×environment interaction (AE) and dominance×environment interaction (DE) effects, and the correlations of A, D, AE and DE effects between BW and its components were estimated. Conditional analysis was employed to investigate the contribution of the components traits to the variances of A, D, AE and DE effects of BW. It was observed that the heritabilities of BW were significantly attributed to A, D and DE by 23.9%, 30.9% and 28.5%, respectively. The variance of A effect for BW was significantly affected by SL, SN and BS by 25.3%, 93.7% and 17.4%, respectively. The variances of D and DE effects for BW were also significantly influenced by all the five components by 5.1%~85.5%. These determinants might be helpful in sugarcane breeding and provide valuable information for multiple-trait improvement of BW.  相似文献   
169.
Objective: To study the effect of halo substitution on disubstituted aryl semicarbazones on the anticonvulsant potential and model the activity based on quantum mechanics. Methods: A series of twenty-six compounds of N^4-(4-bromo-3-methylphenyl) semicarbazones were synthesized and evaluated for the anticonvulsant activity in the maximal electroshock seizure (MES) and subcutaneous pentylenetetrazole (scPTZ) seizure threshold tests. Some potential compounds were also tested in the subcutaneous strychnine (scSTY) and subcutaneous picrotoxin (scPIC) seizure threshold tests. The synthesized compounds were tested for behavioral impairment and CNS (central nervous system) depression in mice. Quantum mechanical modelling was carried out on these compounds to gain understanding on the structural features essential for activity. Results: Some compounds possessed broad spectrum anticonvulsant activity as indicated by their effect in pentylenetetrazole, strychnine, picrotoxin and maximal electroshock seizures models in resemblance to other aryl semicarbazone derivatives reported earlier. The higher the difference in HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) energy levels was, the greater was the activity profile. Conclusion: The pharmacophoric requirements for compounds to exhibit anticonvulsant activity that includes one aryl unit in proximity to a hydrogen donor-acceptor domain and an electron donor have been justified with the molecular orbital surface analysis of the synthesized compounds.  相似文献   
170.
Purpose: To verify whether there exists any difference in higher order aberrations after undergoing myopic LASIK (laser in situ keratomileusis) with conventional ablation and customized ablation in different eyes of the same patient. Methods: This was a prospective randomized study of 54 myopic eyes (27 patients) that underwent LASIK using the Nidek EC-5000 ex-cimer laser system (Nidek, Gamagori, Japan). Topography-guided customized aspheric treatment zone (CATz) was used in the first eye of the patient (study group) and the other eye of the same patient was operated on with conventional ablation (control group). Higher order aberrations [root-mean-square (RMS) in the 5-mm zone] of both groups were observed with the Nidek OPD-Scan aberrometer before and 3 months after LASIK. Preoperative mean refractive error was similar between two eyes of the same patient (t=?0.577, P>0.05). Results: Preoperatively, higher order aberrations (RMS in the 5-mm zone) in the CATz ablation and conventional groups were (0.3600±0.0341) μm and (0.2680±0.1421) μm, respectively. This difference was not statistically significant (t=1.292, P>0.05). Three months after LASIK, higher order aberrations (RMS in 5-mm zone) in the CATz ablation and conventional groups were (0.3627±0.1510) μm and (0.3991±0.1582) μm, respectively. No statistically significant difference was noted between pre- and postoperative higher order aberrations in the CATz group (t=?0.047, P>0.05). However, a statistically significant increase in higher order aberrations was observed after conventional ablation (t=?5.261, P<0.05). A statistically sig-nificant difference was noted in the increase of higher order aberrations after LASIK between groups (t=?2.050, P=0.045). Con-clusion: LASIK with conventional ablation and topography-guided CATz ablation resulted in the same BSCVA (best specta-cle-corrected visual acuity) 3 month after LASIK. Higher order aberrations were increased, but the increase of higher order ab-errations after customized ablation treatment was less than that after conventional ablation.  相似文献   
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