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31.
While various optimization techniques have been used in existing thin client systems to reduce network traffic, the screen updates triggered by many user operations will still result in long interactive latencies in many contemporary network environments. Long interactive latencies have an unfavorable effect on users’ perception of graphical interfaces and visual contents. The long latencies arise when data spikes need to be transferred over a network while the available bandwidth is limited. These data spikes are composed of a large amount of screen update data produced in a very short time. In this paper, we propose a model to analyze the packet-level redundancy in screen update streams caused by repainting of graphical objects. Using this model we analyzed the data spikes in screen update streams. Based on the analysis result we designed a hybrid cache-compression scheme. This scheme caches the screen updates in data spikes on both server and client sides, and uses the cached data as history to better compress the recurrent screen updates in possible data spikes. We empirically studied the effectiveness of our cache scheme on some screen updates generated by one of the most bandwidth-efficient thin client system, Microsoft Terminal Service. The experiment results showed that this cache scheme with a cache of 2M bytes can reduce 26.7%–42.2% data spike count and 9.9%–21.2% network traffic for the tested data, and can reduce 25.8%–38.5% noticeable long latencies for different types of applications. This scheme costs only a little additional computation time and the cache size can be negotiated between the client and server. 相似文献
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Andy Jiang 《计算机网络世界》2009,(11):47-47
2009年度第12期IT品牌评选活动得到众多热心读者的踊跃参与,包括全国各地的业界专家、设计院、系统集成商以及用户等专业人士。此次评选活动,共收到读者们的评选意见回馈表1026份,根据品牌认知、成功案例、价格定位、质量维护、服务支持等多项指标,评选出了十大IT品牌包括综合布线十大产品品牌,以及本次新增加的布线新锐品牌。 相似文献
34.
Andy Shar Phillip Glass Sung Hyun Park Daeha Joung 《Advanced functional materials》2023,33(5):2211079
3D printing of conductive elastomers is a promising route to personalized health monitoring applications due to its flexibility and biocompatibility. Here, a one-part, highly conductive, flexible, stretchable, 3D printable carbon nanotube (CNT)-silicone composite is developed and thoroughly characterized. The one-part nature of the inks: i) enables printing without prior mixing and cures under ambient conditions; ii) allows direct dispensing at ≈100 µm resolution printability on nonpolar and polar substrates; iii) forms both self-supporting and high-aspect-ratio structures, key aspects in additive biomanufacturing that eliminate the need for sacrificial layers; and iv) lends efficient, reproducible, and highly sensitive responses to various tensile and compressive stimuli. The high electrical and thermal conductivity of the CNT-silicone composite is further extended to facilitate use as a flexible and stretchable heating element, with applications in body temperature regulation, water distillation, and dual temperature sensing and Joule heating. Overall, the facile fabrication of this composite points to excellent synergy with direct ink writing and can be used to prepare patient-specific wearable electronics for motion detection and cardiac and respiratory monitoring devices and toward advanced personal health tracking and bionic skin applications. 相似文献
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Previous work has demonstrated that the use of structured abstracts can lead to greater completeness and clarity of information,
making it easier for researchers to extract information about a study. In academic year 2007/08, Durham University’s Computer Science Department revised the format of
the project report that final year students were required to write, from a ‘traditional dissertation’ format, using a conventional
abstract, to that of a 20-page technical paper, together with a structured abstract. This study set out to determine whether
inexperienced authors (students writing their final project reports for computing topics) find it easier to produce good abstracts, in terms of completeness and clarity, when using a structured form rather than a conventional form. We performed
a controlled quasi-experiment in which a set of ‘judges’ each assessed one conventional and one structured abstract for its
completeness and clarity. These abstracts were drawn from those produced by four cohorts of final year students: two preceding
the change, and the two following. The assessments were performed using a form of checklist that is similar to those used
for previous experimental studies. We used 40 abstracts (10 per cohort) and 20 student ‘judges’ to perform the evaluation.
Scored on a scale of 0.1–1.0, the mean for completeness increased from 0.37 to 0.61 when using a structured form. For clarity,
using a scale of 1–10, the mean score increased from 5.1 to 7.2. For a minimum goal of scoring 50% for both completeness and
clarity, only 3 from 19 conventional abstracts achieved this level, while only 3 from 20 structured abstracts failed to reach
it. We conclude that the use of a structured form for organising the material of an abstract can assist inexperienced authors
with writing technical abstracts that are clearer and more complete than those produced without the framework provided by
such a mechanism. 相似文献
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Huicong Liu Cho Jui Tay Chenggen Quan Takeshi Kobayashi Chengkuo Lee 《Microsystem Technologies》2011,17(12):1747-1754
We propose a MEMS piezoelectric energy harvester with a wide operating frequency range by incorporating a high-frequency piezoelectric cantilever and a metal base as the top and bottom stoppers with a low-frequency piezoelectric cantilever. Frequency up-conversion of the piezoelectric energy harvester is realized when the low-frequency piezoelectric cantilever impacts and scrapes through the high-frequency piezoelectric cantilever. For an input acceleration of 0.6?g, with top and bottom stopper distances of 0.75 and 1.1?mm, respectively, the operating frequency ranges from 33 to 43?Hz. The output voltage and power up to 95?mV and 94 nW can be achieved. Experimental results indicate that the frequency up-conversion mechanism significantly improves the effective power. 相似文献
40.
Given much recent discussion and the shift in focus of the field, it is becoming apparent that the incorporation of syntax
is the way forward for improvements to the current state-of-the-art in machine translation (MT). Parallel treebanks are a
relatively recent innovation and appear to be ideal candidates for MT training material. However, until recently there has
been no other means to build them than by hand. In this paper, we describe how we make use of new tools to automatically build
a large parallel treebank and extract a set of linguistically-motivated phrase pairs from it. We show that adding these phrase
pairs to the translation model of a baseline phrase-based statistical MT (PB-SMT) system leads to significant improvements
in translation quality. Following this, we describe experiments in which we exploit the information encoded in the parallel
treebank in other areas of the PB-SMT framework, while investigating the conditions under which the incorporation of parallel
treebank data performs optimally. Finally, we discuss the possibility of exploiting automatically-generated parallel treebanks
further in syntax-aware paradigms of MT. 相似文献