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51.
通过对我国企业统计核算数据要求的分析，提出了ERP系统中的统计核算信息生成模型。该模型使用领域本体论和数据仓库的星型架构技术，通过ETL，最终生成符合我国企业统计核算要求的信息。 相似文献
52.
大型电力变压器短路事故统计与分析 总被引：16，自引：3，他引：16
针对１９９１－１９９５年１１０ＫＶ及以上电压等级变压器的事故情况，统计分析了因外部短路引起电力变压器损坏事故的主要原因，提出了减少这类事故的措施。 相似文献
53.
Cycle time is the total elapsed time to move a unit of work from the beginning to the end of a physical process. It is a variable that is used to reduce the costs and increase the output of the physical process. In this note, the exact probability distribution of the cycle time variable is derived. Exact expressions are provided for its probability density function and moments. It is shown how these results could be used for cycle time reduction. Finally, a computer program and tabulations are provided for the associated percentage points. 相似文献
54.
High Efficiency Video Coding (HEVC) surpasses its predecessors in encoding efficiency by introducing new coding tools at the cost of an increased encoding time-complexity. The Coding Tree Unit (CTU) is the main building block used in HEVC. In the HEVC standard, frames are divided into CTUs with the predetermined size of up to 64 × 64 pixels. Each CTU is then divided recursively into a number of equally sized square areas, known as Coding Units (CUs). Although this diversity of frame partitioning increases encoding efficiency, it also causes an increase in the time complexity due to the increased number of ways to find the optimal partitioning. To address this complexity, numerous algorithms have been proposed to eliminate unnecessary searches during partitioning CTUs by exploiting the correlation in the video. In this paper, existing CTU depth decision algorithms for HEVC are surveyed. These algorithms are categorized into two groups, namely statistics and machine learning approaches. Statistics approaches are further subdivided into neighboring and inherent approaches. Neighboring approaches exploit the similarity between adjacent CTUs to limit the depth range of the current CTU, while inherent approaches use only the available information within the current CTU. Machine learning approaches try to extract and exploit similarities implicitly. Traditional methods like support vector machines or random forests use manually selected features, while recently proposed deep learning methods extract features during training. Finally, this paper discusses extending these methods to more recent video coding formats such as Versatile Video Coding (VVC) and AOMedia Video 1(AV1). 相似文献
55.
Harriet Harriss 《Architectural Design》2019,89(3):18-25
The traditionally institutionalised nature of research can limit its practical relevance and the diversity of individuals involved in it. Practice‐based PhDs are an increasingly popular way of addressing these issues. Harriet Harriss , who leads the Architecture Research Programme at London's Royal College of Art and is a member of the UK Department for Education construction industry panel, outlines their multiple benefits in terms of both student affordability and enhancement of the profession. 相似文献
56.
Rory Hyde 《Architectural Design》2019,89(3):82-89
What use is the business of research, when the business of architecture is on its knees? Rory Hyde – Curator of Contemporary Architecture and Urbanism at the Victoria and Albert Museum, Adjunct Senior Research Fellow at the University of Melbourne, and Design Advocate for the Mayor of London – argues that architectural research can be a vehicle for escaping architecture's current traps: by asking new kinds of questions, developing new kinds of practice models, and rebuilding the social contract between the profession and the public. 相似文献
57.
We propose INDIANA, a system conceived to support a novel paradigm of database exploration. INDIANA assists the users who are interested in gaining insights about a database though an interactive and incremental process, like a conversation that does not happen in natural language. During this process, the system iteratively provides the user with some features of the data that might be “interesting” from the statistical viewpoint, receiving some feedbacks that are later used by the system to refine the features provided to the user in the next step. A key ability of INDIANA is to assist “data enthusiastic” users (i.e., inexperienced or casual users) in the exploration of transactional databases in an interactive way. For this purpose, we develop a number of novel, statistically-grounded algorithms to support the interactive exploration of the database. We report an in-depth experimental evaluation to show that the proposed system guarantees a very good trade-off between accuracy and scalability, and a user study that supports the claim that the system is effective in real-world database-exploration tasks. 相似文献
58.
主要介绍蒸汽发生器传热管通过涡流检查发现缺陷后堵管准则的确定方法,并以田湾核电站卧式蒸汽发生器为例说明堵管准则的计算流程。 相似文献
59.
60.
This study deals with the uncertainty of the measurement of lattice parameters by CBED using the kinematic approximation. The analysis of a large number of diffraction patterns acquired on a silicon sample at 93 K with a LaB6 TEM without energy filter shows the presence of both the systematic and the random parts of errors. It is established that random errors follow the normal statistical distribution and that the precision quantified by the relative standard deviation is about 3–4×10−4 for lattice parameter measurements made from single pattern. The error sources are analyzed, different ways of enhancement are reviewed, and a new approach is proposed. It is shown that both accuracy and precision can be simply improved by taking into account multiple patterns analysis for the determination of the actual voltage, the single lattice parameter “a” or the complete set of lattice parameters. The precision of about 1.5–2×10−4 can be reached using a minimum of three HOLZ line patterns for the single “a” parameter and about 5×10−4 for the complete set of lattice parameters using six diffraction patterns. The use of multiple patterns also allows overcoming the non-uniqueness of solution linked to the CBED studies. 相似文献