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21.
Rebecca C. Hedreen Jennifer L. Johnson Mack A. Lundy Peg Burnette Carol Perryman Guus Van Den Brekel 《国际互联网参考资料服务季刊》2013,18(2-3):167-195
ABSTRACT In April 2006, Alliance Library System and Online Programming for All Libraries partnered to start the Second Life Library 2.0 in the online world Second Life and in August 2006 purchased an island on the Teen grid of Teen Second Life. Second Life is a virtual world, a descendant of multiplayer online games. Educational institutions have recently been drawn into Second Life's robust economy and vibrant cultural life. The Second Life Library 2.0 works with librarians from around the world and with other educational partners such as TechSoup, WorldBridges, and the New Media Consortium. Second Life Library 2.0 provides “traditional” library services such as ready reference, book discussions, and search assistance, but, at heart, it explores what it means to be a virtual library in a virtual world. 相似文献
22.
23.
Steven F. Vaughn Rick A. Boydston Carol A. Mallory-Smith 《Journal of chemical ecology》1996,22(10):1939-1949
Ethyl ether, ethanol, and water extracts of meadowfoam (Limnanthes alba Hartweg ex. Benth.) seedmeal were prepared and bioassayed against velvetleaf (Abutilon theophrasti Medicus) and wheat (Triticum aestivum L. Cardinal). Both the ethyl ether and ethanol fractions, but not the water extract, inhibited velvetleaf and wheat radicle elongation. Fractionation of the extracts indicated that (3-methoxyphenyl)acetonitrile (3-MPAN) was the active compound from both extracts, comprising >97% of the active ethanol fraction. 3-Methoxybenzyl isothiocyanate, which had been previously shown to be the major breakdown product of glucolimnanthin, the majorL. alba glucosinolate, was not detected in either extract. Radicle elongation of velvetleaf and wheat were inhibited by 3-MPAN with I50 (the concentration required to inhibit growth by 50%) values of approximately 4 × 10–4 M (velvetleaf) and 7×10–4 M (wheat).Mention of firms or products does not imply endorsement by the U.S. Department of Agriculture over other firms or products not mentioned. 相似文献
24.
Carol Fung Jie Zhang Issam Aib Raouf Boutaba 《Journal of Network and Systems Management》2011,19(2):257-277
The accuracy of detecting an intrusion within a network of intrusion detection systems (IDSes) depends on the efficiency of
collaboration between member IDSes. The security itself within this network is an additional concern that needs to be addressed.
In this paper, we present a trust-based framework for secure and effective collaboration within an intrusion detection network
(IDN). In particular, we design a trust model that allows each IDS to evaluate the trustworthiness of other IDSes based on
its personal experience. We also propose an admission control algorithm for the IDS to manage the acquaintances it approaches
for advice about intrusions. We discuss the effectiveness of our approach in protecting the IDN against common attacks. Additionally,
experimental results demonstrate that our system yields significant improvement in detecting intrusions. The trust model further
improves the robustness of the collaborative system against malicious attacks. The experimental results also support that
our admission control algorithm is effective and fair, and creates incentives for collaboration. 相似文献
25.
This paper presents a microelectromechanical systems (MEMS) differential thermal biosensor integrated with microfluidics for metabolite measurements in either flow-injection or flow-through mode. The MEMS device consists of two identical freestanding polymer diaphragms, resistive heaters, and a thermopile between the diaphragms. Integrated with polymer-based microfluidic measurement chambers, the device allows sensitive measurement of small volumes of liquid samples. Enzymes specific to a metabolic analyte system are immobilized on microbeads packed in the chambers. When a sample solution containing the analyte is introduced to the device, the heat released from the enzymatic reactions of the analyte is detected by the thermopile. The device has been tested with glucose solutions at physiologically relevant concentrations. In flow-injection mode, the device demonstrates a sensitivity of approximately 2.1 muV/mM and a resolution of about 0.025 mM. In flow-through mode with a perfusion flow rate of 0.5 mL/h, the sensitivity and resolution of the device are determined to be approximately 0.24 muV/mM and 0.4 mM, respectively. These results illustrate that the device, when integrated with subcutaneous sampling methods, can potentially allow for continuous monitoring of glucose and other metabolites. 相似文献
26.
Mobile learning is increasing in popularity, but not all university students have mobile devices to support it. Our study investigated cross-platform software that has the potential to allow education practitioners to provide mobile support to their students’ learning, while offering similar functionality to non-mobile users via more traditional computing platforms. Undergraduate students were trained in the use of multi-platform cloud-based note-taking software (Evernote), and used the software in independent study for 8 weeks. Data show adoption for a range of functions, particularly gathering and managing information, organisation and planning, and the recording of ideas. Multimedia functions were also adopted innovatively by some students. Use for reflection was rare. Non-adopters were in a minority, giving low utility appraisals and difficulty in changing habits as reasons. Subjective evaluations and recommendations showed that a majority of students felt positive about the software and found it quick and easy to use. Mobile and non-mobile users only differed on the number of locations in which they used the software, and the proportion of notes classified as ideas, both being higher in mobile users. The data provide decision support for education practitioners who wish to provide mobile learning to their students alongside traditional platforms. 相似文献
27.
Businesses have embraced the Internet to reap economic advantages through the use of Websites. Most Website design guidelines fail to address issues of branding and identity formation, focusing instead on concerns adapted from previous technologies. However, many firms are not getting their desired results from the Website investments they have made following design guidelines reflecting graphic layout and system usability issues. We suggest that Websites should be considered ‘electronic storefronts’ or public work areas providing frames of symbolic representations that create impressions of their sponsoring firms. Our exploratory study shows that Websites influence potential customers' impressions of firms' legitimacy, innovation and caring, and that these impressions vary significantly across firms and industries. Website visitors encounter symbols that are compared to mental models stored in memory and used to form impressions of the site and to draw inferences about the firm. These inferences have previously been found to influence purchasing behavior. Designers should be cognizant of these aspects of e-Business and executives should recognize the power of Web-based impression management. Identity management must take center stage in creating a Web presence. 相似文献
28.
Applying EuroWordNet to Cross-Language Text Retrieval 总被引:1,自引:0,他引:1
Julio Gonzalo Felisa Verdejo Carol Peters Nicoletta Calzolari 《Computers and the Humanities》1998,32(2-3):185-207
We discuss ways in which EuroWordNet (EWN) can be used in multilingual information retrieval activities, focusing on two approaches to Cross-Language Text Retrieval that use the EWN database as a large-scale multilingual semantic resource. The first approach indexes documents and queries in terms of the EuroWordNet Inter-Lingual-Index, thus turning term weighting and query/document matching into language-independent tasks. The second describes how the information in the EWN database could be integrated with a corpus-based technique, thus allowing retrieval of domain-specific terms that may not be present in our multilingual database. Our objective is to show the potential of EuroWordNet as a promising alternative to existing approaches to Cross-Language Text Retrieval. 相似文献
29.
In a nonclinical sample of 395 young adults, the authors evaluated the relations between major personality traits, Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV; American Psychiatric Association, 1994) personality disorder symptoms, and DSM-IV alcohol use disorders (AUDs). Consistent with previous findings, traits related to disinhibition and negative affectivity were consistently associated with AUDs, as were Cluster B personality disorder symptoms (especially antisocial and borderline disorder symptoms). Multivariate analyses revealed that Cluster B symptoms were significantly associated with AUDs above and beyond what was accounted for by personality traits. Further, the authors found differential patterns of relations between other substance use disorders (SUDs; i.e., tobacco dependence and drug use diagnoses) and personality disorder symptoms. Overall, these results suggest that personality disorder symptoms predict unique variance in SUDs that reflect maladaptive aspects of personality traits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
Hannon Erin E.; Snyder Joel S.; Eerola Tuomas; Krumhansl Carol L. 《Canadian Metallurgical Quarterly》2004,30(5):956
A number of different cues allow listeners to perceive musical meter. Three experiments examined effects of melodic and temporal accents on perceived meter in excerpts from folk songs scored in 6/8 or 3/4 meter. Participants matched excerpts with 1 of 2 metrical drum accompaniments. Melodic accents included contour change, melodic leaps, registral extreme, melodic repetition, and harmonic rhythm. Two experiments with isochronous melodies showed that contour change and melodic repetition predicted judgments. For longer melodies in the 2nd experiment, variables predicted judgments best at the beginning of excerpts. The final experiment, with rhythmically varied melodies, showed that temporal accents, tempo, and contour change were the strongest predictors of meter. The authors' findings suggest that listeners combine multiple melodic and temporal features to perceive musical meter. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献