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41.
The Inductive Query By Example (IQBE) paradigm allows a system to automatically derive queries for a specific Information Retrieval System (IRS). Classic IRSs based on this paradigm [Smith, M., & Smith, M. (1997). The use of genetic programming to build Boolean queries for text retrieval through relevance feedback. Journal of Information Science, 23(6), 423–431] generate a single solution (Boolean query) in each run, that with the best fitness value, which is usually based on a weighted combination of the basic performance criteria, precision and recall.  相似文献   
42.
With the rise of microfluidics for the past decade, there has come an ever more pressing need for a low-cost and rapid prototyping technology, especially for research and education purposes. In this article, we report a rapid prototyping process of chromed masks for various microfluidic applications. The process takes place out of a clean room, uses a commercially available video-projector, and can be completed in less than half an hour. We quantify the ranges of fields of view and of resolutions accessible through this video-projection system and report the fabrication of critical microfluidic components (junctions, straight channels, and curved channels). To exemplify the process, three common devices are produced using this method: a droplet generation device, a gradient generation device, and a neuro-engineering oriented device. The neuro-engineering oriented device is a compartmentalized microfluidic chip, and therefore, required the production and the precise alignment of two different masks.  相似文献   
43.
Separation and sorting of biological entities (viruses, bacteria, and cells) is a critical step in any microfluidic lab-on-a-chip device. Acoustofluidics platforms have demonstrated their ability to use physical characteristics of cells to perform label-free separation. Bandpass-type sorting methods of medium-sized entities from a mixture have been presented using acoustic techniques; however, they require multiple transducers, lack support for various target populations, can be sensitive to flow variations, or have not been verified for continuous flow sorting of biological cells. To our knowledge, this paper presents the first acoustic bandpass method that overcomes all these limitations and presents an inherently reconfigurable technique with a single transducer pair for stable continuous flow sorting of blood cells. The sorting method is first demonstrated for polystyrene particles of sizes 6, 10, and 14.5 μm in diameter with measured purity and efficiency coefficients above 75 ± 6% and 85 ± 9%, respectively. The sorting strategy was further validated in the separation of red blood cells from white blood cells and 1 μm polystyrene particles with 78 ± 8% efficiency and 74 ± 6% purity, respectively, at a flow rate of at least 1 μl/min, enabling to process finger prick blood samples within minutes.  相似文献   
44.
Tumor lysis syndrome has been observed in patients with malignancies with high cellular burden and high cell turnover, tumor sensitive to therapy, especially after initiating medical treatment. It very rarely occurs spontaneously. The case described here is of 6 months male infant who presented with fever since 1 month and loose stools associated with blood since 15 days. The laboratory investigations showed lactate dehydrogenase (LDH) of 6,192 IU/L and serum uric acid 18.2 mg/dl along with pancytopenia. The infant presented with electrolyte abnormalities and renal failure.  相似文献   
45.
The purpose of this paper is to compute the Hankel transform Fn(y) of order n of a function f(x) and its inverse transform using rationalized Haar wavelets. The integrand is replaced by its wavelet decomposition. Thus representing Fn(y) as a Fourier-Bessel series with coefficients depending strongly on the local behavior of the function , thereby getting an efficient algorithm for their numerical evaluation. Numerical evaluations of test functions with known analytical Hankel transforms illustrate the proposed algorithm.  相似文献   
46.
In this paper, the problem of stability analysis for neural networks with time-varying delays is considered. By the use of a newly augmented Lyapunov functional and some novel techniques, sufficient conditions to guarantee the asymptotic stability of the concerned networks are established in terms of linear matrix inequalities (LMIs). Three numerical examples are given to show the improved stability region of the proposed works.  相似文献   
47.
利用双标图分析基因型和环境交互作用   总被引:28,自引:0,他引:28  
在作物的品种区域化试验中,品种的基因型和环境(G×E)交互作用越来越受到重视.一种新的非常有效的分析G×E交互作用模型是加性主效应和乘积交互作用模型(简称AMMI模型),而双标图(biplot)是解释AMMI分析结果的一种直观有效的图形工具.本文对AMMI模型及双标图作一扼要介绍,并选用1995年南方水稻区试单季晚粳组数据作为实例,给出了两种新的双标图,以帮助我们更深入地了解G×E交互作用.  相似文献   
48.
依托多种资源,开展产学合作教育是应用型本科高校培养创新人才的重要途径。文章从合作教育视角探讨了池州学院经管类专业"面向市场,服务地方,合作办学,特色发展"的办学思路及经管类专业合作教育培养人才的资源整合问题;构建了经管类专业合作教育的人才培养目标及以能力为平台的课程教学体系;基于地方智库、产学合作平台建设、职业技能培养三类合作教育模式,探索总结池州学院经管类专业应用型创新人才培养的途径和方法。  相似文献   
49.
通过对喀什地区维吾尔族中学生心理健康状况调查,了解他们的心理健康状况,采取有针对性的干预措施,为促进维吾尔族中学生的健康成长提供理论依据。  相似文献   
50.
Daryao  S.  Khatri Anne  O.  Hughes 《美中教育评论》2013,(10):739-753
As part of a doctoral dissertation, Ben (2010) completed a study that extends to 462 pages. After a careful examination of this study and others that are in print, there seems to be a direct relationship between the decline in physics enrollment at the postsecondary level and the increase in the number of studies that have been carried out to determine why have we been off the mark in identifying the real problems that are contributing to the declining enrollment and the decreased student success in physics courses? One problem is introductory physics books are generally written using a deductive approach, and because the teachers follow the organization of these books, they teach in a deductive, boring, and confusing way, and then, blame the students for being unprepared when they do not succeed. This approach distances the teachers--and physics--from the experience, knowledge, and initial interest of many beginning students. Another problem has been the absence of any alternative curriculum to the deductive one. In this paper, we describe a fully-developed alternative curriculum, really a detailed course design for Introductory College Physics I and II, each with its own text presented in the format of a three-ring binder, one for students and one for teachers which closely parallel one another. The course content is constructed to be both teacher and student friendly, so that a teacher can teach physics in an inductive, exciting, and clear manner. In addition, we describe and provide examples of the pedagogical and classroom management techniques that have proven extremely successful.  相似文献   
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