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991.
Jianhan Zhu Xiangji Huang Dawei Song Stefan Rüger 《Knowledge and Information Systems》2010,23(1):29-54
We argue that expert finding is sensitive to multiple document features in an organizational intranet. These document features
include multiple levels of associations between experts and a query topic from sentence, paragraph, up to document levels,
document authority information such as the PageRank, indegree, and URL length of documents, and internal document structures
that indicate the experts’ relationship with the content of documents. Our assumption is that expert finding can largely benefit
from the incorporation of these document features. However, existing language modeling approaches for expert finding have
not sufficiently taken into account these document features. We propose a novel language modeling approach, which integrates
multiple document features, for expert finding. Our experiments on two large scale TREC Enterprise Track datasets, i.e., the
W3C and CSIRO datasets, demonstrate that the natures of the two organizational intranets and two types of expert finding tasks,
i.e., key contact finding for CSIRO and knowledgeable person finding for W3C, influence the effectiveness of different document
features. Our work provides insights into which document features work for certain types of expert finding tasks, and helps
design expert finding strategies that are effective for different scenarios. Our main contribution is to develop an effective
formal method for modeling multiple document features in expert finding, and conduct a systematic investigation of their effects.
It is worth noting that our novel approach achieves better results in terms of MAP than previous language model based approaches
and the best automatic runs in both the TREC2006 and TREC2007 expert search tasks, respectively. 相似文献
992.
993.
According to actual needs, a generalized signcryption scheme can flexibly work as an encryption scheme, a signature scheme or a signcryption scheme. In this paper, firstly, we give a security model for identity based generalized signcryption which is more complete than the existing model. Secondly, we propose an identity based generalized signcryption scheme. Thirdly, we give the security proof of the new scheme in this complete model. Compared with existing identity based generalized signcryption, the new scheme has less implementation complexity. Moreover, the new scheme has comparable computation complexity with the existing normal signcryption schemes. 相似文献
994.
Recent advances in algorithms for the multidimensional multiple choice knapsack problems have enabled us to solve rather large problem instances. However, these algorithms are evaluated with very limited benchmark instances. In this study, we propose new methods to systematically generate comprehensive benchmark instances. Some instances with special correlation properties between parameters are found to be several orders of magnitude harder than those currently used for benchmarking the algorithms. Experiments on an existing exact algorithm and two generic solvers show that instances whose weights are uncorrelated with the profits are easier compared with weakly or strongly correlated cases. Instances with classes containing similar set of profits for items and with weights strongly correlated to the profits are the hardest among all instance groups investigated. These hard instances deserve further study and understanding their properties may shed light to better algorithms. 相似文献
995.
In product design process, when dealing with technical problems or initiating a new design, R&D personnel would often turn to technical database to seek inspiration. The building of a database with such documents has not been systematically dealt with. In this paper, several issues on how to build up a product design database are investigated: input source, sampling scheme and quality control. A case study of building a database for robotic design is used to demonstrate the concept. It is an archive of more than 1500 relevant technical papers. A total of 16 graduates are employed as operators in the labeling process and subsequently the hypothesis tests are utilized to process the labeling results. To ensure this database quality, the labeling consistency of each operator and the understanding of each category are tested. With the use of statistical methods, this work proposes a feasible and practical way to create such a database for product design. 相似文献
996.
997.
Ling Zhu 《Computers & Mathematics with Applications》2010,59(2):724-736
In this work, two general forms of Jordan’s inequalities for the Bessel and modified Bessel functions are established, and proved by using l’Hospital’s rule for monotonicity and some properties of the spherical Bessel and the modified spherical Bessel functions of the first kind. The applications of the results above give two new infinite series for the Bessel and modified Bessel functions. 相似文献
998.
Xin Ma Xinlong Xu Zheng Zheng Kun Wang Yalin Su Jiangfeng Fan Rui Zhang Lusheng Song Zhiyou Wang Jinsong Zhu 《Sensors and actuators. A, Physical》2010,157(1):9-14
An electro-optically modulated intensity interrogation method based on tunable waveguide coupled surface plasmon resonance sensors has been proposed. It has been theoretically and experimentally demonstrated that the proposed scheme can enable sensitive measurement of measurand variations. By modulating the refractive index in the waveguide layer, this interrogation method yields modulated signal whose amplitude is related to measurand's refractive index. This amplitude modulated signal offers a higher signal to noise ratio and eliminates additive noise in the sensor system. A preliminary investigation using saline buffers with different NaCl concentrations shows a resolution of 2.3 × 10?6 refractive index unit by our approach. Resolution can be controlled by the amplitude of the applied modulation voltage and can be further enhanced by optimizing the device structure or improving the electro-optical (E-O) coefficient of the E-O material. This approach is simple, stable, and promising for low-cost or multi-channel SPR biosensor applications. 相似文献
999.
Surgery to reshape the nose with an implant has been a regular procedure for enhancing a patient’s appearance and self-confidence.
The purpose of this study was to establish a computed tomography (CT) based three-dimensional assistant plastic surgery systems,
which can provide the patients with realistic prediction of their own postoperative appearance in computer and specifically
produce a nose implant for an individual patient. Preoperative CT data and 3D reconstruction techniques were employed to generate
3D model of the patient’s skull. 3D collision detection and finite elements model deformation were then applied to simulate
nose augmentation surgery and predict postoperative appearance. According to the patient’s expectation, digital models of
the nose implants were constantly modified. When the patient is satisfied with the simulated results, custom made silicone
implants were produced by a computer controlled device. Accurately regeneration of 3D images and realistic operative simulations
could be achieved with this system. The implants produced exactly conformed to the results of simulation. No curving and reshaping
were needed during operating. The clinical results extremely matched with the simulations. The system enhances surgeon patient
communication and facilitates preoperative planning. It is especially desirable for implant surgery with less guesswork of
size, contour, and orientation of the implant. The best chance of optimal results could be achieved. 相似文献
1000.
This paper considers the existence of the equilibrium point and its global exponential robust stability for reaction-diffusion
interval neural networks with variable coefficients and distributed delays by means of the topological degree theory and Lyapunov-functional
method. The sufficient conditions on global exponential robust stability established in this paper are easily verifiable.
An example is presented to demonstrate the effectiveness and efficiency of our results. 相似文献