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41.

Locative Media Experiences (LMEs) have significant potential in enabling visitors to engage with the places that they visit through an appreciation of local history. For example, a visitor to Berlin that is exploring remnants of the Berlin Wall may be encouraged to appreciate (or in part experience) the falling of the Berlin wall by consuming multimedia directly related to her current location such as listening to audio recordings of the assembled crowds on 10th November 1989. However, despite the growing popularity of enabling technologies (such as GPS-equipped smart phones and tablets), the availability of tools that support the authoring of LMEs is limited. In addition, mobile apps that support the consumption of LMEs typically adopt an approach that precludes users from being able to respond with their own multimedia contributions. In this article we describe the design and evaluation of the SHARC2.0 framework that has been developed as part of our long-term and participatory engagement with the rural village of Wray in the north of England. Wray has very limited cellular data coverage which has placed a requirement on the framework and associated tools to operate without reliance on network connectivity. A field study is presented which featured a LME relating to Wray’s local history and which contained multimedia content contributed by members of the community including historic photos (taken from an existing ‘Digital Noticeboard’ system), audio-clips (from a local historian and village residents) and video (contributed during a design workshop). The novelty of our approach relates to the ability of multiple authors to contribute to a LME in-situ, and the utilisation of personal cloud storage for storing the contents associated with a multi-authored LME.

  相似文献   
42.
This report provides an overview of physical ergonomic exposures in highway construction work across trades and major operations. For each operation, the observational method “PATH” (Posture, Activity, Tools and Handling) was used to estimate the percentage of time that workers spent in specific tasks and with exposure to awkward postures and load handling. The observations were carried out on 73 different days, typically for about 4 h per day, covering 120 construction workers in 5 different trades: laborers, carpenters, ironworkers, plasterers, and tilers. Non-neutral trunk postures (forward or sideways flexion or twisting) were frequently observed, representing over 40% of observations for all trades except laborers (28%). Kneeling and squatting were common in all operations, especially tiling and underground utility relocation work. Handling loads was frequent, especially for plasterers and tilers, with a range of load weights but most often under 15 pounds. The results of this study provide quantitative evidence that workers in highway tunnel construction operations are exposed to ergonomic factors known to present significant health hazards. Numerous opportunities exist for the development and implementation of ergonomic interventions to protect the health and safety of construction workers.  相似文献   
43.
This paper describes our initial effort in developing a trilingual speech interface for financial information inquiries. Our foreign exchange inquiry system consists of: (i) monolingual and trilingual speech recognizers, which receive the user's spoken input in the form of microphone speech; (ii) a real-time data capture component which continuously updates a relational database from a financial data satellite feed; and (iii) a trilingual speech generation component, which generates English and Chinese text based on the raw financial data. The generated text is then transformed into spoken presentations. English text is processed by the FESTIVAL synthesizer system. Chinese text is sent to our syllable-based synthesizer, which employs a concatenative resequencing technique to produce spoken presentations in Putonghua or Cantonese. The speech interface is augmented with a visual display which aims to provide feedback to the user at all times during an interaction. Within the restricted scope of foreign exchange (FOREX), our recognition performance accuracies remain above 93%. Confusions across languages contributed significantly to our recognition errors, but most are confusions between the same currency/country names spoken in different languages. These errors are not detrimental with respect to data retrieval. Our concatenative re-sequencing technique reports the date, time and exchange rates of the input currency pair. A demonstration can be found at http://www.se.cuhk.edu.hk/hccl/demos/.  相似文献   
44.
Protein isolates extracted from rumen, lung and plasma by alkaline solubilisation were spun into protein fibres and were evaluated for protein quality by rat feeding trials and by amino acid analyses. The net protein utilisation (NPU) of the fibres ranged from 53·0 to 76·9 for plasma and rumen fibres respectively, methionine plus cystine and valine being limiting amino acids. Lysine was not found to be a limiting amino acid in any sample and lysine availability was high in isolates and fell only slightly on spinning. There was a marked discrepancy between chemical score and NPU for rumen isolate and it is postulated that an anti-nutritional factor, possibly a trypsin inhibitor, normally present in bovine organs, could be active in the isolate by lowering methionine availability to the animal and decreasing NPU. Spinning the proteins, however, either destroys the inhibitor or decreases its concentration since NPU and chemical score become equal.  相似文献   
45.
This paper reports on a pilot investigation into web conferencing in a distance learning module. It focuses on the perceptions and experiences of the tutors, all of whom were new to the web conferencing environment, but were experienced in online teaching. A number of web conferencing tutorials were studied through the collection of various datasets, mostly qualitative. The data were analysed by a team of researchers, informed by key literature in this area.The main findings from the pilot indicated that tutors experienced challenges in creating social presence and in managing cognitive load when dealing with multiple tasks online. There were also technical obstacles to improvisation in response to students’ emerging needs. The findings of the pilot informed the training and support provided when web tutorials were subsequently rolled out to all tutorial groups (approximately 140) in the module. Overall, experiences from the web tutorials indicate that tutors and students reacted positively to the opportunities web conferencing provides for interactive learning and teaching.  相似文献   
46.
The lipase-catalyzed synthesis of ester bonds has been well-documented lately and is of much current commercial interest. Immobilization of a fungal lipase on a unique macroporous support allows not only the ability to operate in non-aqueous media but to catalyze ester synthesis in quantitative yields, employing attractive commercial conditions. Catalyst dose and process configurations will be illustrated. The capability of the catalyst to operate efficiently in reverse under a variety of unnatural, hostile, solvent-containing environments will be discussed. The range of substrates for this immobilized lipase, Lipzome, has been investigated. The enzyme will catalyze ester synthesis with saturated, unsaturated and a variety of branched carboxylic acids. The alcohol specificity for this enzyme also is equally broad. A wide variety of straight-chain, branched and polar alcohols can be substrates. In addition, some examples of alcohol specificity for kinetic isomer resolution will be cited. Presented at the symposium “The Biology, Biotechnology and Technology of Lipases” at the 78th annual meeting of the American Oil Chemists’ Society held May 17–21, 1987, in New Orleans, Louisiana.  相似文献   
47.
The effect of Al2O3 and Nb2O5 additions on the microstructure and thermal expansion behavior of tantalum (V) oxide has been studied. Both singly doped and co-doped compositions were examined. Compositions with 3 wt% Al2O3 (or greater), contained AlTaO4 as a second phase. Complete solubility was observed for Nb2O5 contents in the range 1–5 wt%. It was found that doping with Al2O3 results in a decrease of the coefficient of thermal expansion (CTE), such that increasing amounts of Al2O3 (1–5 wt%) cause a successive decrease in the CTE value. In the case of Nb2O5 additions, the result is an increase in the CTE of the tantalum (V) oxide. However, in the range 1–5 wt% Nb2O5, the CTE value is relatively insensitive to the amount of Nb2O5 added. Due to the countervailing influences of these two additive oxides, it was demonstrated that co-doping with Al2O3 and Nb2O5 is an effective strategy for tailoring the CTE of tantalum (V) oxide.  相似文献   
48.
Early Head Start, a federal program begun in 1995 for low-income pregnant women and families with infants and toddlers, was evaluated through a randomized trial of 3,001 families in 17 programs. Interviews with primary caregivers, child assessments, and observations of parent-child interactions were completed when children were 3 years old. Caregivers were diverse in race-ethnicity, language, and other characteristics. Regression-adjusted impact analyses showed that 3-year-old program children performed better than did control children in cognitive and language development, displayed higher emotional engagement of the parent and sustained attention with play objects, and were lower in aggressive behavior. Compared with controls, Early Head Start parents were more emotionally supportive, provided more language and learning stimulation, read to their children more, and spanked less. The strongest and most numerous impacts were for programs that offered a mix of home-visiting and center-based services and that fully implemented the performance standards early. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
This paper explores a formalism for describing a wide class of multimedia document constraints, based on an interval temporal logic. We describe the requirements that arise from the multimedia documents application area, and we illustrate these requirements using several examples. Then we present the temporal logic formalism that we use. This logic extends existing interval temporal logic with a number of new features: actions, framing of actions, past operators, a projection-like operator called filter and a new handling of interval length. The notation is applied to the specification of the examples, and in particular a set of logical manipulations, providing feedback to an author, is presented. A model theory, logic and satisfaction relation are defined for the notation.  相似文献   
50.
This study of continuing care for substance dependent patients compared a telephone-based monitoring and brief counseling intervention (TEL) with 2 face-to-face interventions, relapse prevention (RP) and standard 12-step group counseling (STND). The participants were graduates of intensive outpatient programs who had current dependence on alcohol and/or cocaine. Self-report, collateral, and biological measures of alcohol and cocaine use were obtained over a 12-month follow-up. The treatment groups did not differ on abstinence-related outcomes in the complete sample (N = 359) or on cocaine use outcomes in participants with cocaine dependence (n = 268). However, in participants with alcohol dependence only (n = 91), TEL produced better alcohol use outcomes than STND on all measures examined and better outcomes than RP on some of the measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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