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91.
We define the emerging research field of applied data science as the knowledge discovery process in which analytic systems are designed and evaluated to improve the daily practices of domain experts. We investigate adaptive analytic systems as a novel research perspective of the three intertwining aspects within the knowledge discovery process in healthcare: domain and data understanding for physician- and patient-centric healthcare, data preprocessing and modelling using natural language processing and (big) data analytic techniques, and model evaluation and knowledge deployment through information infrastructures. We align these knowledge discovery aspects with the design science research steps of problem investigation, treatment design, and treatment validation, respectively. We note that the adaptive component in healthcare system prototypes may translate to data-driven personalisation aspects including personalised medicine. We explore how applied data science for patient-centric healthcare can thus empower physicians and patients to more effectively and efficiently improve healthcare. We propose meta-algorithmic modelling as a solution-oriented design science research framework in alignment with the knowledge discovery process to address the three key dilemmas in the emerging “post-algorithmic era” of data science: depth versus breadth, selection versus configuration, and accuracy versus transparency. 相似文献
92.
Xiaofeng Liao Xueming Li Jun Pen Guanrong Chen 《International Journal of Communication Systems》2004,17(5):437-445
In this paper, a simple image secure communication scheme based on the chaotic Chebyshev map and chaos synchronization is proposed. The scheme relies on the excellent correlation property of chaotic sequences, which is very desirable for secure image communication. The results obtained by computer simulation indicate that the transmitted source image can be correctly and reliably recovered using the proposed scheme, even through a noisy channel. Notably, the scheme possesses relatively high security and can be easily implemented. Moreover, the quality of the recovered image is satisfactory, quantified by such common criteria as the bit‐error rate performance. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
93.
D. Candusso F. Harel A. De Bernardinis X. François M.C. Péra D. Hissel P. Schott G. Coquery J.-M. Kauffmann 《International Journal of Hydrogen Energy》2006
In the framework of the French inter lab SPACT project (fuel cell systems for transportation applications), a 10 kW PEM fuel cell testing bench has been installed in 2002 in the national fuel cell test platform located in Belfort, France. The behaviour of a 5 kW fuel cell, fed with humidified pure hydrogen gas and compressed air, has been investigated by the Laboratory of Electrical Engineering and Systems (L2ES) in association with the French National Institute for Transport and Safety Research (INRETS). 相似文献
94.
According to one survey on energy consumption in Iran, commercial and building sector consume more energy than any other economic sectors. For example, about 38% of total energy that consumed in year 2001 has been used for space heating. Insulation in external walls of buildings has an important role to reduce the environmental effects on indoor space condition. Therefore, always using insulation is an alternative to avoid from the energy loss. In this paper, the effects of the using of a proper insulation on the energy saving in Iranian buildings are studied. For this purpose, an integrative modelling is used for simulation of the energy consumption in buildings. It is shown that energy consumption per square meter of buildings can be reduced up to 35.2% when insulation is used for external walls. 相似文献
95.
This paper presents a computationally efficient method for using the dynamic wake meandering model to conduct simulations of wind farm power production. The method is based on creating a database, which contains the time and rotor‐averaged wake effect at any point downstream of a wake‐emitting turbine operating in arbitrary ambient conditions and at an arbitrary degree of wake influence. This database is later used as a look‐up table at runtime to estimate the operating conditions at all turbines in the wind farm, thus eliminating the need to run the dynamic wake meandering model at runtime. By using the proposed method, the time required to conduct wind farm simulations is reduced by three orders of magnitude compared with running the standalone dynamic wake meandering model at runtime. As a result, the wind farm production dynamics for a farm of 100 turbines at 10,000 different sets of ambient conditions run on a normal laptop in 1 h. The method is validated against full scale measurements from the Smøla and OWEZ wind farms, and fair agreement is achieved. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
96.
A simple theoretical equation of state is derived by applying the Tower-Well potential model about the molecular distribution
based on the generalized van der Waals partition function. It needs only three molecular parameters which have distinct physical
meanings. The resulting equation of state predicts rather well the vapor pressures, saturated liquid volumes, saturated vapor
volumes and PVT thermodynamic properties of polar and structurally complex molecules over a wide temperature and pressure
range. 相似文献
97.
从图同构角度给出树同构的性质,并阐述了结构异构与结构对齐之间的关系.在此基础上为建立结构映射关系,以及在翻译过程中融入句法结构信息,提出元结构、互译结构组概念及多层次结构对齐的体系.最后利用对数线性模型,给出基于元结构对齐的统计机器翻译模型.模型的翻译过程中,源语言句法树以元结构为单位进行分解,利用互译结构组映射知识,转换为目标语言句法树结构序列,从而根据结构模型信息对目标语实施调序和译文的生成.实验结果表明,本模型在对于翻译知识的泛化能力和翻译结果方面都优于基于短语的统计机器翻译模型. 相似文献
98.
For thick resist implant layers, such as a high voltage P well and a deep N well, systematic and uncorrectable overlay residues brought about by the tapered resist profiles were found. It was found that the tapered profile is closely related to the pattern density. Potential solutions of the manufacturing problem include hardening the film solidness or balancing the exposure density. In this paper, instead of focusing on the process change methodology,we intend to solve the issue of the overlay metrology error from the perspective of the overlay mark design. Based on the comparison of the overlay performances between the proposed overlay mark and the original design, it is shown that the optimized overlay mark target achieves better performance in terms of profiles, dynamic precision,tool induced shift (TIS), and residues. Furthermore, five types of overlay marks with dummy bars are studied, and a recommendation for the overlay marks is given. 相似文献
99.
当前的数字音频编码算法使用复杂的模型来最大化编码效率,同时使得失真最小。由于这种复杂性,对相同未压缩的输入音频,采用不同编码器压缩音频时往往会产生不同的输出音频。在统计分析了已压缩音频码流特征的基础上,采用SVM(支持向量机)分类器来确定最可能的13种编码器的矢量特性,提出了一种方法来辨识基于MPEG-1 Layer III(MP3)标准音频文件的编码器类型。测试结果表明准确度可以达到95%左右,并且可以通过加入新的码流特征来进一步提高辨识结果的准确性。因此,这种方法可以被视为一种辨识MP3编码器类型的通用方法。 相似文献
100.
Lexicalized reordering models are very important components of phrasebased translation systems.By examining the reordering relationships between adjacent phrases,conventional methods learn these models from the word aligned bilingual corpus,while ignoring the effect of the number of adjacent bilingual phrases.In this paper,we propose a method to take the number of adjacent phrases into account for better estimation of reordering models.Instead of just checking whether there is one phrase adjacent to a given phrase,our method firstly uses a compact structure named reordering graph to represent all phrase segmentations of a parallel sentence,then the effect of the adjacent phrase number can be quantified in a forward-backward fashion,and finally incorporated into the estimation of reordering models.Experimental results on the NIST Chinese-English and WMT French-Spanish data sets show that our approach significantly outperforms the baseline method. 相似文献