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91.
《国际互联网参考资料服务季刊》2013,18(2):51-72
Abstract Without prior searching instruction, undergraduate novices wrote structured self-reports during their first session on a Web search engine. Users chose their own topics and followed written instructions that prompted them to describe thoughts and feelings during specified stages of the search: pre-search formulation; search statement formulation; search strategy; and evaluation of results. The sentences in the self-reports were numbered and then coded according to their affective or cognitive function. The affective sentences reveal how users set goals and limit the scope of the cognitive operations. Search acts appear to be governed by an affective filter that organizes incoming information and provides criteria for ranking cognitive relevance to search goal. The cognitive sentences reveal a variety of operations in executing searches. Following the search, students made self-ratings on self-confidence as searchers and satisfaction with the search experience, with explanations of their ratings. Content analysis identified reasons users have for rating self-confidence, stress level, satisfaction, usefulness, and success with future searches. 相似文献
92.
《国际互联网参考资料服务季刊》2013,18(2-3):11-33
Abstract Library professionals in the information age are called upon to provide user-friendly information environments. To accomplish this, more detailed knowledge is needed about the information behavior of users. The concept “information counseling” reflects this new orientation and involves instruction activities such as: orienting, advising, and reassuring novice learners. The taxonomic approach transforms self-witnessing reports into classified segments of information behaviors at three levels of internalization and in three behavioral domains, including: affective, cognitive, and sensorimotor behavior. Reference librarians and instructors are invited to contribute to the taxonomy and make use of it in planning and designing programs and facilities. This behavioral inventory of information behaviors learning the Internet is presented with illustrative entries under each category for affective and cognitive behavior. Suggested uses for the inventory include promoting information self-counseling skills, helping learners overcome technophobia through generational self-witnessing reports, and creating better point-of-use instructions for novices using complex information systems. 相似文献
93.
Michael Fowler 《Digital Creativity》2013,24(4):275-287
NURBS (non-uniform rational b-spline) modelling has become a ubiquitous tool within architectural design praxis. In this article I examine three projects that utilise NURBS modelling as a means for which a musical system's inherent spatiality is visualised. There are numerous precedents for which architectural form is a derivation of a musical system, or a musical system is proportionally informed by architectonic gesture. I propose in this article three NURBS modelling methodologies: for the spatial analysis of Karlheinz Stockhausen's sound projection geometries in Pole für 2; for a spatial realisation of John Cage's indeterminate work Variations III; and for the generation of a surface manifold informed by musically derived soundscape data from the Japanese garden Kyu Furukawa Teien. Rather than seeking to translate music into inhabitable architecture, or architectonic form into music, I highlight an approach that produces an interstitial territory between discourses on architecture and music analysis. 相似文献
94.
Toxic and Potent Chinese Materia Medica (T/PCMM) is a special and very important category of Chinese medicines. They have long been used in traditional medical practice and are being used more and more widely throughout the world in recent years. As there may be many fatal toxic effects caused by misusing or confusion of T/PCMM, their quality and safety control arouse increasing attention internationally. Researches on the accurate identification to ensure the safe use of T/PCMM are acquired; however, there are few reports on authentication. We are carrying out a series of studies on 31 T/PCMM originating from plants, animals, minerals, and secreta. In our previous studies, we proved that modern microscopic authentication is a simple, fast, effective, low cost, and less toxic method for identifying animal, seed, and flower T/PCMM. In the present study, we focused on the authentication of four kinds of mineral arsenicals, including orpiment (mainly containing As2S3), realgar (mainly containing As4S4), arsenolite, and arsenic trioxide (mainly containing As2O3). We examined the macroscopic and microscopic characteristics of the above minerals and found that they all can be easily identified and authenticated by using light microscopy coupled with polarized microscopy. Moreover, the authentication results for arsenolite and arsenic trioxide are confirmed by ICP‐MS analysis. We are sure that the morphological and microscopic characteristics indicated here are indispensable to establishing standards for these four mineral T/PCMMs. Microsc. Res. Tech. 74:1‐8, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
95.
提出了基于蕴涵算子族G-λ-∏的模糊推理的思想,这将有助于提高推理结果的可靠性。针对蕴涵算子族G-λ-∏给出了模糊推理的FMP模型及FMT模型的三I支持算法、α-三I支持算法。 相似文献
96.
在传统的秘密共享方案中,秘密分发者通过秘密通道分发秘密份额给一组参与者.结合Rei方案和Amos方案,提出仅需一个秘密通道的秘密共享方案.在该方案的秘密分发阶段,秘密分发者与参与者之间使用部分广播通道进行通信,秘密分发者与秘密合并者之间使用一个秘密通道进行通信;在秘密重构阶段,参与者与秘密合并者之间使用广播通道进行通信.通过对该方案进行分析可知,该方案的通道数和总的通信量比已知的两个方案具有明显的优势. 相似文献
97.
Aldo Badano 《Journal of the Society for Information Display》2009,17(11):891-896
Abstract— In this work, the effect of display temporal characteristics on detectability of signals was studied by comparing detection performance with a slow liquid‐crystal‐display (LCD) monitor and a fast, cathode‐ray‐tube (CRT) monitor when browsing multi‐slice image datasets in stack‐mode presentation. Thirteen readers evaluated 200 image sequence pairs in a two‐alternative forced choice experiment. The image sets consisted of three‐dimensional cluster lumpy backgrounds and were presented to the readers in two display devices: a three‐million‐pixel medical color LCD and a color desktop CRT. For the LCD, many inter‐gray‐level transitions are on the order of 50–60 msec, which was almost twice the frame time. The CRT had 2–5‐msec inter‐gray‐level transitions. The reader study was performed with a graphical‐user interface programmed using direct calls to OpenGL libraries to precisely control the browsing speed. The results were analyzed in terms of the difference in reader performance for each reader and each display, between a browsing speed of 20 and 50 frames per sec (fps). Average reader performance difference between 20 and 50 fps was measured to be 0.049 and 0.156 for the CRT and LCD monitors, respectively. The corresponding drop in reader performance associated with slow display was 0.11. 相似文献
98.
Dharani Perera R. T. Jim Eales Kathy Blashki 《Universal Access in the Information Society》2009,8(2):77-88
For people with upper limb disabilities visual art is an important activity that allows for expression of individuality and
independence. They show remarkable endurance, patience and determination to adapt their remaining capabilities to create visual
art. There are significant advantages of digital technologies in assisting artists with upper limb disabilities. Paralinguistic
voice recognition technologies have proven to be a particularly promising mode of interaction. Despite these benefits, technological
support for people with upper limb disabilities to create visual art is scarce. This paper reports on a number of case studies
of several artists with upper limb disabilities. These case studies illustrate the struggles they face to be creative and
also show the significant advantages of digital technologies in assisting such artists. An investigation into people’s ability
to use the volume of their voice to control cursor movement to create drawings on the screen is also reported. With motivation,
training and practise, use of volume to control drawing tasks shows great promise. It is believed that paralinguistic voice
has wider implications beyond assisting artists with upper limb disabilities, such as: an alternative mode of interaction
for disabled people to perform tasks other than creating visual art, alternative mode of interaction for hands busy environments
and as a voice training system for people with speech impairments. 相似文献
99.
Marcello La Rosa Wil M. P. van der Aalst Marlon Dumas Arthur H. M. ter Hofstede 《Software and Systems Modeling》2009,8(2):251-274
Variability management is a recurrent issue in systems engineering. It arises for example in enterprise systems, where modules
are configured and composed to meet the requirements of individual customers based on modifications to a reference model.
It also manifests itself in the context of software product families, where variants of a system are built from a common code
base. This paper proposes an approach to capture system variability based on questionnaire models that include order dependencies
and domain constraints. The paper presents analysis techniques to detect circular dependencies and contradictory constraints
in questionnaire models, as well as techniques to incrementally prevent invalid configurations by restricting the space of
allowed answers to a question based on previous answers. The approach has been implemented as a toolset and has been used
in practice to capture configurable process models for film post-production.
相似文献
Arthur H. M. ter HofstedeEmail: |
100.
Achieving stability is the essential issue in the control system design. In this paper, four approaches that can be used to calculate the stability margin of the interval plant family are summarized and compared. The μ approach gives the bounds of the stability margin, and good estimation can be obtained with the numerical method. The eigenvalue approach yields accurate value, and the MATLAB's function robuststab sometimes provides wrong results. Since the eigenvalue approach is both accurate and computationally efficient, it is recommended for the calculation of the stability margin, while utilization of the function robuststab should be avoided due to the unreliable results it gives. 相似文献