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261.
With increasing popularity of the Internet and tremendous amount of on-line text, automatic document classification is important for organizing huge amounts of data. Readers can know the subject of many document fields by reading only some specific Field Association (FA) words. Document fields can be decided efficiently if there are many FA words and if the frequency rate is high. This paper proposes a method for automatically building new FA words. A WWW search engine is used to extract FA word candidates from document corpora. New FA word candidates in each field are automatically compared with previously determined FA words. Then new FA words are appended to an FA word dictionary. From the experiential results, our new system can automatically appended around 44% of new FA words to the existence FA word dictionary. Moreover, the concentration ratio 0.9 is also effective for extracting relevant FA words that needed for the system design to build FA words automatically.  相似文献   
262.
Quality objective physical activity data are required to inform physical activity-based health improvement initiatives, however, various challenges undermine acquisition of such data. We examined the efficacy and challenges of a hip-worn accelerometry protocol in women. Specific objectives included determining accelerometer-wear-compliance rates and understanding the barriers and acceptability of wearing accelerometers. Healthy New Zealand women (n?=?406) of three ethnicities (Māori (indigenous New Zealander), Pacific, European) aged 16–45 years (30.9?±?8.7 y) wore hip-mounted Actigraph wGT3X+ accelerometers for 7 consecutive days under a 24-h wear protocol. Post hoc, a sub-sample (n?=?45; age: 29.4?±?9.0 y) was interviewed to investigate comfort/convenience and burdens of accelerometer-wear. Wear-compliance (≥10?h/day, ≥4 day) was 86%. European women returned more valid data (92.7%, p?<?.04) than Pacific (73.0%) or Māori women (82.1%). Twenty-two participants (5.4%) had completely missing data; 13 due to lost accelerometers. Burden of accelerometer-wear was greatest during sleeping (66.7%) due to discomfort. Embarrassment of accelerometer visibility through clothing and consequent restricted clothing choices caused high burden in social settings (45.2%). Discomfort during sleeping, embarrassment due to perceived appearance in social settings and ethnicity are key factors affecting the efficacy of collecting physical activity data from women using hip-worn accelerometers. Refining accelerometer design to reduce size and subsequently participant burden should improve acceptability and wear-compliance. Increasing overall participant compliance by reducing burden and ensuring appropriate understanding of study aims and relevance should reduce attrition and improve wear-compliance and data quality when collecting accelerometry data from women of different ethnicities.  相似文献   
263.
The term technochange refers to technology-driven organizational changes and covers the broad spectrum of aspects that are related to and have an impact on changes within organizations. Technochange processes are usually managed by change managers, who are responsible for successfully accomplishing the IT-related tasks in their projects, as well as every other structural and organizational dimension related to the implementation of technochanges. This paper discusses what competencies managers should have to carry out these processes effectively. On the basis of the existing literature, interviews with experts and case study research, we identify and test a set of IT- and non-IT-related competencies that are essential for managing technochange processes within and among organizations. Further, this paper presents a model for assessing and allocating project managers to IT technochange projects that match their competencies and skills. This model could also serve as a tool for developing technochange management competencies via targeted training programmes. A case study demonstrates how the assessment model can be used in practice. Finally, we make some suggestions for future research in the fields of change management and IT.  相似文献   
264.
This paper applies concepts drawn from KM to Art Education. Specifically, the purpose of this paper is to study the knowledge types, knowledge sources, knowledge processes as well as factors affecting these processes in Art Education. The research was carried out using an interpretative case study methodology in Singapore. Apart from 26 one-to-one interviews conducted with various stakeholders of the Art Education community, on-site observations were made at 19 different Art Education events. Four major findings emerged. One, the knowledge types of Art Education in Singapore were a blend of different knowledge domains. Two, perceptible knowledge sources were those which conveyed an appearance of authority. Three, knowledge processes in Art Education were steeply humanistic. Finally, factors that affected knowledge processes were (i) the highly competitive Singapore education system, (ii) management support and policies, (iii) personal values and interests, (iv) workload and (v) the absorptive capacity of Art teachers. This paper concludes with a number of research and practical implications.  相似文献   
265.
This study surveyed reactions and preferences related to a support program for siblings of children with disabilities. Following participation in a support group, 40 school-age siblings of children with disabilities completed a questionnaire about what they learned from the program and what program components they preferred. The results identified the benefits the participants received and the program components they preferred. Clinical utility is suggested for school personnel planning or implementing support programs for siblings of children with disabilities. © 1998 John Wiley & Sons, Inc.  相似文献   
266.
Recent legislation in New Zealand has placed statutory obligations on its government organizations to introduce sound records management practices and to ensure long-term access to their digital records. To obtain a base level of knowledge on current digital preservation practices and on awareness of digital preservation issues, an online survey was conducted of the nation's government organizations in March 2006. The survey, which achieved a response rate of 42.4%, found that most organizations were knowledgeable about basic aspects of their digital resources but their awareness of digital preservation was generally low, and digital preservation activity was modest overall. To identify possible reasons for this situation, Rogers' (Diffusion of innovations. 5th ed. New York: Free Press. 2003) Diffusion of Innovations model is used to discuss digital preservation as an innovation and the level of readiness for digital preservation as the innovation's rate of adoption. The paper concludes by using Rogers' model as the basis for making recommendations aimed at helping the government's lead agencies to increase New Zealand's public sector readiness for digital preservation.  相似文献   
267.
野营     
Lily 《阅读》2010,(7):64-65
露营地点应选择在干燥,地势较高,通风良好,蚊虫较少的地方。通常,湖泊附近和通风的山脊、山顶是夏天较为理想的设营地点。  相似文献   
268.
There is ongoing debate about how to define injury in dance: the most encompassing one or a time-loss definition. We examined the relationship between touring, performance schedule and injury definition on injury rates in a professional modern dance company over one-year. In-house healthcare management tracked 35 dancers for work-related musculoskeletal injuries (WMSI), time-loss injuries (TLinj), complaints, and exposure. The year was divided into 6 segments to allow comparison of effects of performance, rehearsal, and touring. Injuries/segment were converted into injuries/1000-h dance exposure. We conducted negative binomial regression analysis to determine differences between segments, P ≤ 0.05. Twenty WMSI, 0.44 injuries/1000-h, were sustained over one-year. WMSI were 6 times more likely to occur in Segment-6, compared with other segments (incident rate ratio = 6.055, P = 0.031). The highest rate of TLinj and traumatic injuries also occurred in Segment-6, reflecting concentrated rehearsal, New York season and performances abroad. More overuse injuries occurred in Segment-2, an international tour, attributed to raked stages. Lack of methods to quantify performance other than injury may mask effects of touring on dancer’s well-being. Tracking complaints permits understanding of stressors to specific body regions and healthcare utilisation; however, TLinj remain the most important injuries to track because they impact other dancers and organisational costs.  相似文献   
269.
Projective synchronization is a type of chaos synchronization where the response system states are scaled replicas of the drive system states. This paper deals with the propagation of projective synchronization in a series connection of N chaotic discrete-time drive systems and N response systems. By exploiting an observer-based approach, the paper demonstrates that dead-beat projective synchronization (i.e., exact synchronization in finite time for any scaling factor) is achieved between the nth drive and nth response systems. In particular, it is shown that projective synchronization starts from the innermost (Nth) drive-response system pair and propagates toward the outermost (first) drive-response system pair. Only a single scalar synchronizing signal connects the cascaded drive and response systems. Finally, an example illustrates the propagation of different types of chaos synchronization in a series connection consisting of a Gingerbreadman map, a third order hyperchaotic Henon map and a Lozi map.  相似文献   
270.
Organic synthesis of natural products began in 1828 with Wohler's synthesis of urea, the first time a substance derived from a living organism had been produced by combining inorganic materials. Progress in the field was slow at first, due to the limited purification and analytical methods. Advances in those areas gave rise to rapid progress in synthesis, as chemists could now focus their energies on devising new approaches to the preparation of increasingly complex molecules. While it is possible to prepare many molecules by using known chemistry in new combinations, real progress has been the result of keen insight and creativity on the part of only a few individuals.Professor Samuel J. Danishefsky established himself early on as a leader in this field when he recognized that a well-known ring forming reaction could be greatly extended by adding chemical functionality to one of the components. He then found that these new reactive components could react with heretofore unreactive components to produce new rings containing oxygen atoms both in the ring and as attachments to the ring. These products were very similar to naturally occurring sugars. Danishefsky realized that he could develop this chemistry further to produce precisely defined polysaccharides as well. Some of these polysaccharides occur on the surface of cancer cells. Using the chemistry he developed, he was able to prepare these cancer cell markers, and after combining them with certain proteins, showed that the resulting molecules behaved as cancer vaccines. Several have entered clinical trial.Danishefsky has synthesized many other natural products, but he is particularly interested in those that may be useful in treating cancer. His syntheses allow for the modification of the final product in ways that improve both safety and efficacy. Several of these compounds have also entered clinical trials. Thus his work has not only advanced the art and science of organic synthesis, but stands to make dramatic advances in the treatment of cancer as well.  相似文献   
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