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111.
Patent documents are unique external sources of information that reveal the core technology underlying new inventions.Patents also serve as a strategic data source that can be mined to discover state-of-the-art technical development and subsequently help guide R&D investments.This research incorporates an ontology schema to extract and represent patent concepts.A clustering algorithm with non-exhaustive overlaps is proposed to overcome deficiencies with exhaustive clustering methods used in patent mining and technology discovery.The non-exhaustive clustering approach allows for the clustering of patent documents with overlapping technical findings and claims,a feature that enables the grouping of patents that define related key innovations.Legal advisors can use this approach to study potential cases of patent infringement or devise strategies to avoid litigation.The case study demonstrates the use of non-exhaustive overlaps algorithm by clustering US and Japan radio frequency identification (RFID) patents and by analyzing the legal implications of automated discovery of patent infringement. 相似文献
112.
GAO Zhi-wei Ho Daniel W. C. WANG Xian-lai LI Guang-quan . Tianjin University Tianjin China . City University of Hong Kong Kowloon Hong Kong China 《系统科学与系统工程学报(英文版)》2000,(1)
1 IntroductionConsider a singular decentralized control system of the formEx(t) =Ax(t) ∑Ni=1Biui(t)yi =Cix(t) ,i∈ N ={ 1 ,2 ,… ,N}(1 )where x(t)∈ Rn is the state vector,ui(t)∈ Rmi and yi(t)∈ Rpi are respectively the localcontrol input and measure outputvectors of the ith control channel.The matrix E may besingular,i.e.,rank(E) 相似文献
113.
Shaw C 《Population trends》2000,(99):4-12
The 1998-based national population projections, carried out by the Government Actuary in consultation with the Registrars General, show the population of the United Kingdom rising from 59.2 million in 1998 to over 63.5 million by 2021. Longer-term projections suggest the population will peak around 2036 and then gradually start to fall. The population will become gradually older with the median age expected to rise from 36.9 years in 1998 to nearly 42 years by 2021. In 1998, there were 1.4 million (13 per cent) more children aged under 16, than people of pensionable age. However, by 2008, the population of pensionable age is projected to exceed the number of children. 相似文献
114.
Daniel S. Yeung Wing W. Y. Ng Aki P. F. Chan Patrick P. K. Chan Michael Firth Eric C. C. Tsang 《系统科学与系统工程学报(英文版)》2007,16(2):166-180
Company bankruptcies cost billions of dollars in losses to banks each year. Thus credit risk prediction is a critical part of a bank's loan approval decision process. Traditional financial models for credit risk prediction are no longer adequate for describing today's complex relationship between the financial health and potential bankruptcy of a company. In this work, a multiple classifier system (embedded in a multiple intelligent agent system) is proposed to predict the financial health of a company. In our model, each individual agent (classifier) makes a prediction on the likelihood of credit risk based on only partial information of the company. Each of the agents is an expert, but has limited knowledge (represented by features) about the company. The decisions of all agents are combined together to form a final credit risk prediction. Experiments show that our model out-performs other existing methods using the benchmarking Compustat American Corporations dataset. 相似文献
115.
On-chip natural assembly of silicon photonic bandgap crystals. 总被引:20,自引:0,他引:20
Photonic bandgap crystals can reflect light for any direction of propagation in specific wavelength ranges. This property, which can be used to confine, manipulate and guide photons, should allow the creation of all-optical integrated circuits. To achieve this goal, conventional semiconductor nanofabrication techniques have been adapted to make photonic crystals. A potentially simpler and cheaper approach for creating three-dimensional periodic structures is the natural assembly of colloidal microspheres. However, this approach yields irregular, polycrystalline photonic crystals that are difficult to incorporate into a device. More importantly, it leads to many structural defects that can destroy the photonic bandgap. Here we show that by assembling a thin layer of colloidal spheres on a silicon substrate, we can obtain planar, single-crystalline silicon photonic crystals that have defect densities sufficiently low that the bandgap survives. As expected from theory, we observe unity reflectance in two crystalline directions of our photonic crystals around a wavelength of 1.3 micrometres. We also show that additional fabrication steps, intentional doping and patterning, can be performed, so demonstrating the potential for specific device applications. 相似文献
116.
Water capture by a desert beetle. 总被引:15,自引:0,他引:15
Some beetles in the Namib Desert collect drinking water from fog-laden wind on their backs. We show here that these large droplets form by virtue of the insect's bumpy surface, which consists of alternating hydrophobic, wax-coated and hydrophilic, non-waxy regions. The design of this fog-collecting structure can be reproduced cheaply on a commercial scale and may find application in water-trapping tent and building coverings, for example, or in water condensers and engines. 相似文献
117.
Superconductivity in CaCuO2 as a result of field-effect doping. 总被引:2,自引:0,他引:2
J H Sch?n M Dorget F C Beuran X Z Zu E Arushanov C Deville Cavellin M Lagu?s 《Nature》2001,414(6862):434-436
Understanding the doping mechanisms in the simplest superconducting copper oxide-the infinite-layer compound ACuO2 (where A is an alkaline earth metal)-is an excellent way of investigating the pairing mechanism in high-transition-temperature (high-Tc) superconductors more generally. Gate-induced modulation of the carrier concentration to obtain superconductivity is a powerful means of achieving such understanding: it minimizes the effects of potential scattering by impurities, and of structural modifications arising from chemical dopants. Here we report the transport properties of thin films of the infinite-layer compound CaCuO2 using field-effect doping. At high hole- and electron-doping levels, superconductivity is induced in the nominally insulating material. Maximum values of Tc of 89 K and 34 K are observed respectively for hole- and electron-type doping of around 0.15 charge carriers per CuO2. We can explore the whole doping diagram of the CuO2 plane while changing only a single electric parameter, the gate voltage. 相似文献
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