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1.
Ontologies are becoming increasingly important in a variety of different fields, such as intelligent searching on the web, knowledge sharing and reuse, knowledge management, etc. Therefore, we expect that the need for tools to support the construction of ontologies will increase significantly in the coming years. In this paper, we investigate several of these tools. We evaluate the tools using two different ontologies: a simple one about university employees, and a second, more complex one, about the structure of a university study. The evaluation was conducted using a framework, which incorporates aspects of ontology buildings and testing, as well as cooperation with other users. Our conclusions are that the usefulness of the tools depends on the level of the users and the stage of development of the ontology.  相似文献   

2.

Background

Online learning and teaching were globally popularized due to the impact of Covid-19. The pandemic has made both synchronous and asynchronous online learning inevitable in regions privileged with the technological affordance.

Aims

This study was designed to examine and compare the effectiveness of both learning modes through the Community of Inquiry framework.

Materials & Methods

Comparative analyses on a sample of N = 170 undergraduate students who took both synchronous and asynchronous online courses in Spring 2021.

Results

The paired-sample T-tests results indicated a significant difference in social presence, cognitive presence and self-evaluated performance.

Discussion & Conclusion

Teaching presence significantly influenced social presence and cognitive presence in both learning modes. However, under synchronous learning mode, social presence significantly impacted self-evaluation, grades and school identification. While social presence only influenced school identification under asynchronous learning mode. Theoretical and practical implications were also included.  相似文献   

3.

Is it really better to print everything, including software models, or is it better to view them on screen? With the ever increasing complexity of software systems, software modeling is integral to software development. Software models facilitate and automate many activities during development, such as code and test case generation. However, a core goal of software modeling is to communicate and collaborate. Software models are presented to team members on many mediums and two of the most common mediums are paper and computer screens. Reading from paper or screen is ostensibly considered to have the same effect on model comprehension. However, the literature on text reading has indicated that the reading experiences can be very different which in turn effects various metrics related to reader performance. This paper reports on an experiment that was conducted to investigate the effect of reading software models on paper in comparison with reading them on a computer screen with respect to cognitive effectiveness. Cognitive effectiveness here refers to the ease by which a model reader can read a model. The experiment used a total of 74 software engineering students as subjects. The experiment results provide strong evidence that displaying diagrams on a screen allows subjects to read them quicker. There is also evidence that indicates that on screen viewing induces fewer reading errors.

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4.
One major challenge regarding the use of today's language labs relates to teachers' and students' awareness and computer skills. Most teachers and students may not have the requisite computer skills and might soon become overwhelmed by the sophisticated functionality of today's digital lab systems. Thus, they should be provided with the appropriate training and technical support to reduce the apprehension that is usually associated with new technology. Recurrent technical problems are another shortcoming. Failure to operate the lab equipment efficiently due to hardware or software problems will inevitably cause delays and frustration for both students and instructors.To overcome such problems in existing language labs, this paper presents a novel cross-platform mobile lab system for language learning, called Mlab. The target users of MLab are language teachers and students, and the system offers them the freedom to move around and use their own devices at any time and in any place. Therefore, this research paper presents Mlab development and evaluation through three approaches: a holistic test case scenario, think aloud and interview sessions. The results showed high usability rates and generally positive attitudes toward using the mobile lab system.  相似文献   

5.
Security and privacy policies address consumer concerns related to security and privacy in e-commerce websites. As these policies represent only the vendor’s perspective, often there exists a mismatch between the stated and desired policy. Based on transaction cost theory, we speculate that business-to-business (B2B) and business-to-consumer (B2C) e-commerce customers use their transaction cost savings in order to obtain varying levels of security and privacy. These differences are bound to be reflected in the security and privacy policies of e-commerce companies. Therefore, in this paper, we perform a comparative content analysis of the security and privacy policies in B2C and B2B e-commerce. Results show that B2B vendors are more concerned about security than their B2C counterparts, while B2C vendors are anxious about intimacy and restriction privacy. Our findings have important implications for e-commerce consumers and vendors as individual and corporate consumers have varying concerns while transacting online. Individual consumers are concerned about maintaining security and intimacy privacy, whereas corporate users are anxious about regulatory issues. Therefore, B2C vendors should incorporate stringent measures dedicated to confidentiality and protection of consumer data as well as enhance intimacy privacy in their security policies, while their B2B counterparts should focus on enhancing restriction privacy.  相似文献   

6.
Recently, concerns have been raised that adolescents’ prolific social media use may cause them to become less empathic. However, direct empirical evidence is missing and research suggests that social media use can also be beneficial for adolescents’ psychosocial development. The present study aims to investigate whether and how social media use influences empathy. We surveyed 942 Dutch adolescents (10–14 years) twice, with a one-year interval. The results showed that social media use is related to an increase in cognitive and affective empathy over time. Specifically, adolescents’ social media use improved both their ability to understand (cognitive empathy) and share the feelings of their peers (affective empathy).  相似文献   

7.
《Ergonomics》2012,55(5):765-772
Is the weather forecast better recalled when presented on TV or radio? In three successive experiments it was found that radio presentation leads to quite low recall scores (22–29%). It is extremely hard to improve these scores by the addition of TV pictures. It does not help to show the newscaster presenting the message; neither does the addition of geographical maps enhance the subsequent recall. A positive effect was obtained by presenting animated pictograms or written summary statements, but the effect was small: recall scores did not surpass 34%.  相似文献   

8.
The objective of this study was to determine the quality of MEDLINE searches done by physicians, physician trainees, and expert searchers (clinicians and librarians). Its design was an analytic survey with independent replication in a setting of self-service online searching from medical wards, an intensive care unit, a coronary care unit, an emergency room, and an ambulatory clinic in a 300-bed teaching hospital. Participating were all M.D. clinical clerks, house, and attending staff responsible for patients in the above settings. Intervention for all participants consisted of a 2-h small group class and 1-h practice session on MEDLINE searching (GRATEFUL MED) before free access to MEDLINE. Search questions from 104 randomly selected novice searches were given to 1 of 13 clinicians with prior search experience and 1 of 3 librarians to run independent searches (triplicated searches). Measurements and main results from these unique citations of the triplicated searches were sent to expert clinicians to rate for relevance (7-point scale). Recall (number of relevant citations retrieved from an individual search divided by the total number of relevant citations from all searches on the same topic) and precision (proportion of relevant citations retrieved in each search) were calculated. Librarians were significantly better than novices for both. Librarians had equivalent recall to, and better precision than, experienced end-users. Unexpectedly, only 20% of relevant citations were retrieved by more than one search of the set of three, with the conclusion that novice searchers on MEDLINE via GRATEFUL MED after brief training have relatively low recall and precision. Recall improves with experience but precision remains suboptimal. Further research is needed to determine the "learning curve," evaluate training interventions, and explore the non-overlapping retrieval of relevant citations by different searchers.  相似文献   

9.

Visually impaired individuals often rely on assistive technologies such as white canes for independent navigation. Many electronic enhancements to the traditional white cane have been proposed. However, only a few of these proof-of-concept technologies have been tested with authentic users, as most studies rely on blindfolded non-visually impaired participants or no testing with participants at all. Experiments involving blind users are usually not contrasted with the traditional white cane. This study set out to compare an ultrasound-based electronic cane with a traditional white cane. Moreover, we also compared the performance of a group of visually impaired participants (N = 10) with a group of blindfolded participants without visual impairments (N = 31). The results show that walking speed with the electronic cane is significantly slower compared to the traditional white cane. Moreover, the results show that the performance of the participants without visual impairments is significantly slower than for the visually impaired participants. No significant differences in obstacle detection rates were observed across participant groups and device types for obstacles on the ground, while 79% of the hanging obstacles were detected by the electronic cane. The results of this study thus suggest that electronic canes present only one advantage over the traditional cane, namely in its ability to detect hanging obstacles, at least without prolonged practice. Next, blindfolded participants are insufficient substitutes for blind participants who are expert cane users. The implication of this study is that research into digital white cane enhancements should include blind participants. These participants should be followed over time in longitudinal experiments to document if practice will lead to improvements that surpass the performance achieved with traditional canes.

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10.
11.
Nowadays, multi-core processor is the main technology used in desktop PCs, laptop computers and mobile hardware platforms. As the number of cores on a chip keeps increasing, it adds up the complexity and impacts more on both power and performance of a processor. In multi-processors, the number of cores and various parameters, such as issue-width, number of instructions and execution time, are key design factors to balance the amount of thread-level parallelism and instruction-level parallelism. In this paper, we perform a comprehensive simulation study that aims to find the optimum number of processor cores in desktop/laptop computing processor models with shallow pipeline depth. This paper also explores the trade-off between the number of cores and different parameters used in multi-processors in terms of power–performance gains and analyzes the impact of 3D stacking on the design of simultaneous multi-threading and chip multiprocessing. Our analysis shows that the optimum number of cores varies with different classes of workloads, namely: SPEC2000, SPEC2006 and MiBench. Simulation study is presented using architectures with shorter pipeline depth, showing that (1) the optimum number of cores for power–performance is 8, (2) the optimum number of threads in the range [2, 4], and (3) for beyond 32 cores, multi-core processors are no longer efficient in terms of performance benefits and overall power consumption.  相似文献   

12.
Zhang  Zhi  Guo  Yingshi  Fu  Rui  Yuan  Wei  Yang  Guosong 《Cognition, Technology & Work》2020,22(4):759-767
Cognition, Technology & Work - Previous research has identified cognitive and situational factors as causes of risky driving; however, little is known about what roles cognitive and situational...  相似文献   

13.
14.
This study aimed to examine the influence of crowd flow on human evacuation behavior during building fire emergencies, when evacuees perceive high uncertainty in the environment and experience mental stress. Evacuation experiments were conducted in an immersive virtual metro station, in which each participant was presented with one of three different patterns of crowd flow and asked to complete an evacuation task. The patterns of crowd flow were represented by non-player characters that split differently at each wayfinding decision point in the metro station. The experiments were conducted in Beijing, Los Angeles and London. The results showed that uneven splits of crowd flow motivated participants under mental stress to follow the majority of the crowd. This influence of crowd flow was generally consistent over the course of evacuation, and such consistency could be reinforced by stronger directional information conveyed by the crowd flow as well as positive feedback from the outcomes of previous wayfinding decisions. The results also indicated that the influence of crowd flow was significant in all three cultures represented by the three cities, however, the impact of culture on how participants would respond to the directional information conveyed by the crowd flow was insignificant.  相似文献   

15.
Dear editor, Implementation attacks such as fault attack(FA)[1]and side-channel analysis (SCA)[2]are signifi-cant threats to the cryptographic device security.I...  相似文献   

16.
17.
Multimodal fusion is a complex topic. For surveillance applications audio–visual fusion is very promising given the complementary nature of the two streams. However, drawing the correct conclusion from multi-sensor data is not straightforward. In previous work we have analysed a database with audio–visual recordings of unwanted behavior in trains (Lefter et al., 2012) and focused on a limited subset of the recorded data. We have collected multi- and unimodal assessments by humans, who have given aggression scores on a 3 point scale. We showed that there are no trivial fusion algorithms to predict the multimodal labels from the unimodal labels since part of the information is lost when using the unimodal streams. We proposed an intermediate step to discover the structure in the fusion process. This step is based upon meta-features and we find a set of five which have an impact on the fusion process. In this paper we extend the findings in (Lefter et al., 2012) for the general case using the entire database. We prove that the meta-features have a positive effect on the fusion process in terms of labels. We then compare three fusion methods that encapsulate the meta-features. They are based on automatic prediction of the intermediate level variables and multimodal aggression from state of the art low level acoustic, linguistic and visual features. The first fusion method is based on applying multiple classifiers to predict intermediate level features from the low level features, and to predict the multimodal label from the intermediate variables. The other two approaches are based on probabilistic graphical models, one using (Dynamic) Bayesian Networks and the other one using Conditional Random Fields. We learn that each approach has its strengths and weaknesses in predicting specific aggression classes and using the meta-features yields significant improvements in all cases.  相似文献   

18.
Workstations at school are among several factors that contribute to musculoskeletal symptoms among school-aged children. The aim of this study was to investigate the effects of ergonomically designed workstations on schoolchildren's musculoskeletal symptoms as compared to conventional workstations. In the first 14-month phase of the study (2002-2003, two schools), 42 from the intervention and 46 from the control school participated. In the total follow-up of 26 months (2002-2004), 23 in the intervention group and 20 in the control group participated. Anthropometrics and musculoskeletal symptoms were measured. In general, the ergonomically designed school workstations did not decrease present neck-shoulder, upper back, low back and lower limbs strain and pain, compared to conventional ones during follow-ups.  相似文献   

19.
This study focuses on big data, including data from social networking sites (SNS), and data that can complement prior researches on TV viewing rate prediction. The paper analyzes the variables, which influence the average minute rating (AMR) and share rating (SHR) through regression analysis after gathering buzz data on a 20-episode drama series in Korea. The R-square value of regression analysis results shows that the consumer-generated media (CGM) variable including SNS items explained 64 % of both AMR and SHR. However, the Media variable is not statistically significant. For SNS items, the Korean SNS me2DAY and DaumYozm are statistically significant for AMR and SHR, but Twitter is not significant. This study contributes to practitioners’ ability to alleviate the hurdles of broadcasting production communities on the difficulty of predicting viewing rate in advance. Thus, it is possible to determine whether to invest production cost persistently or to adjust the broadcasting volume based on viewers’ response.  相似文献   

20.
The COVID-19 pandemic has been the world's greatest challenge since World War II. As an unprecedented global public health crisis, crisis management teams (CMTs) in the infected countries need to rethink to cope with the similar uncertainty and urgency of the ongoing COVID-19 pandemic. The shared context of COVID-19 allows us to explore a cross-nation study of different constructs and CMT to communicate information about crises with the public effectively. Since the pandemic affected all countries, the comparison is warranted. Can CMTs mitigate the effects of COVID-19? Based on the analysis of China and the US cases, our study explores how shared and common knowledge cognition among crisis responders plays a pivotal role in effective CMTs' communication while technological failures and inadequate information disrupt the system, worsening pandemics like COVID-19. Furthermore, organizational dysfunction, such as institutional fragmentation, regulatory hurdles and bureaucratic arrogance, impede effective communication between CMTs. However, effective coordination and decisive leadership could improve coordination effectiveness and reduce crisis costs.  相似文献   

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