To obtain and maintain user models are very important for personalized service *** quality of personalized services directly relies on the quality of the user *** surprisingly,many web sites have adopted different way...
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To obtain and maintain user models are very important for personalized service *** quality of personalized services directly relies on the quality of the user *** surprisingly,many web sites have adopted different ways to construct user models so that they can recommend goods or services to individuals according to user's preference. Obviously,to integrate separate user models coming from different sources for one user can provide more comprehensive and accurate user *** there exist the requirements to obtain integrated user models by sharing their user models. After discussing the requirements of sharing user models,an open user model service platform is ***'s architecture, key technologies and an implemented prototype are introduced.
This paper studies an actual and new setting of cost-sensitive learning,i.e.,combining test data with medical history under multiple-scale cost *** a new cost structure,an attribute selection strategy is incorporated ...
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This paper studies an actual and new setting of cost-sensitive learning,i.e.,combining test data with medical history under multiple-scale cost *** a new cost structure,an attribute selection strategy is incorporated to a lazy decision tree induction,so as to minimize the total cost on focused scale when medical history is dynamically utilized to current test *** experiments on six medical datasets in the UCI library demonstrate that the proposed lazy cost-sensitive decision tree algorithm has outperformed a group of existing costsensitive learning algorithms in a cost/budget-changing environment.
In order to solve the defects of ViBe moving object detection algorithm, an improved algorithm based on spatialtemporal gradient has been proposed. According to the complexity and the changes of the background, parame...
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In order to solve the defects of ViBe moving object detection algorithm, an improved algorithm based on spatialtemporal gradient has been proposed. According to the complexity and the changes of the background, parameters of discrimination mechanism have been adjusted adaptively. The mean of spatial gradients has been calculated to adjust the detection radius, which is capable of improving the detection accuracy. According to the illumination invariant of the spatial gradient, the light information has been removed, which is able to reduce the disturbance of shadow. The sum of bivariate temporal gradients has been counted so as to adjust the threshold, which can suppress the fallout ratio caused by the changes of background. Based on the temporal gradient of consecutive frames, the background changes have been detected, which achieved the rapid elimination of "ghost". Through the experiment, the improved algorithm and other algorithms were compared and analyzed in three indicators(FPR, FNR and PWC). The experimental results show that the improved algorithm has a good effect in removing the shadow and eliminating the "ghost". Meanwhile, it has a better overall performance on several indicators compared with other algorithms.
For low permeability bottom water reservoir fracturing, it is easy that hydraulic fracture penetrate into aquifer zones and lead to problematic production of water when potentially productive zones are located a few m...
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For low permeability bottom water reservoir fracturing, it is easy that hydraulic fracture penetrate into aquifer zones and lead to problematic production of water when potentially productive zones are located a few meters above water or the interlaminar stress contrast is not big enough. Swellable particle plugging agent as a new profile control agent has been applied widely and achieved good results. In order to ensure the performance of bottom water fracturing with swellable agent, the shut-off capacity and intensity on pore has been tested by physical model experiments and a new mathematic model for artificial barrier has been proposed. It can provide some reference on reasonable application of swellable plugging agent in bottom water reservoir fracturing. The application results in Luliang oilfield show that swellable plugging agent can effectively seal water layer and achieved a significant increase of oil production.
This article studied on the rotation motion of trimaran unmanned surface *** experiment has been based on the trimaran unmanned surface vessel *** selected the Grenetic algorithm as the optimization method first, then...
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This article studied on the rotation motion of trimaran unmanned surface *** experiment has been based on the trimaran unmanned surface vessel *** selected the Grenetic algorithm as the optimization method first, then identified the test data of trimaran unmanned surface vessel rotation motion by the program assisted with ISIGHTFD *** compared the identified results with the test data and analyzed the error,we got the identified result matched the test result well from a set of compared data plots. The trimaran unmanned surface vessel model and its control system have important value for research and have good reference value for practical applications of unmanned surface
The hydraulic bulging strengthening technology is a kind of strengthening technology of large generator's retaining *** ring billet is deformed uniformly by the super pressure water while the punch working angle i...
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The hydraulic bulging strengthening technology is a kind of strengthening technology of large generator's retaining *** ring billet is deformed uniformly by the super pressure water while the punch working angle is 60°and the pressure between the punch and the rings is *** the deformation process the thickness of the ring must be controlled accurately. Using ultrasound sensors which the accuracy can achieve 0.1mm to measure real-time thickness of the ring billet can greatly improve the *** the pressure of the oilhydraulic machine and ultra-high pressure pump with virtual instrument may improve *** experiment in 5MN oil-hydraulic machine proves that the external generatrices of the ring billet are nearly line after the thickness deformations of the top,middle and bottom of the ring billet are 1.49mm,1.69mm and *** ring billet is 1/5 of 300MW18-18 steel retaining ring.
Modeling technology is the key to the advancement of road & bridge construction problem solving *** light of the existing defects of problem-solving modeling technology,a new function graphic modeling technology w...
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Modeling technology is the key to the advancement of road & bridge construction problem solving *** light of the existing defects of problem-solving modeling technology,a new function graphic modeling technology which can reflect problem solving characteristics is *** on function graphic object which has engineering properties of lengthvariable and unstructured,and can exist independently and work cooperatively with each other,a group of function graphic objects are used to emulate planed road & bridge construction sub-problem,and solving process is carried out interactively and dynamically by creating,operating,and deducing function graphic *** the proposed function graphic modeling technology,the traditional modeling method and realization model of road & bridge construction problem solving are broken through,and a new modeling and realization technology system which is suitable for solving characteristics of road & bridge construction problem is set up.
As an advanced on-board data transmission protocol, Avionics Full Duplex Ethernet(AFDX) was initiated by Airbus in the evolution of its A380 *** this paper,we deduce several properties of an AFDX network and present a...
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As an advanced on-board data transmission protocol, Avionics Full Duplex Ethernet(AFDX) was initiated by Airbus in the evolution of its A380 *** this paper,we deduce several properties of an AFDX network and present an AFDX System Integration Algorithm(ASIA) to guide the topology design of an AFDX network as well as Virtual Link(VL) parameters determination. We also propose an Integrity Checking(IC) algorithm based on the difference of the sequence numbers between redundant *** algorithm reasonably expands the reception range of valid frames and avoids potential deadlock,thus greatly enhancing the reliability of AFDX protocol.
Spread spectrum(SS) is one of the most commonly used watermarking techniques, but it suffers from host signal interference during watermark extraction. Besides the wellknown developments of classical host interference...
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Spread spectrum(SS) is one of the most commonly used watermarking techniques, but it suffers from host signal interference during watermark extraction. Besides the wellknown developments of classical host interference rejecting SS techniques, i.e., improved spread spectrum(ISS) and correlationaware improved spread spectrum(CAISS), a simple and effective treatment could be splitting the host signal into two channels(even-sample channel and odd-sample channel) before watermark embedding. Host signal interference is then suppressed by reconstructing the channels and taking the difference of them. This paper analyzes such a dual channel scheme from the perspective of digital filtering. We show that the dual channel based watermark extraction actually applies a high pass filter to the watermarked signal, and the performance when the filter coefficients are changed is also studied. The effectiveness of the dual channel scheme in rejecting host signal interference is confirmed via extensive experiments using both synthetic and real audio and image signals.
Software development is a human-centric activity. Developers often spend valuable time carrying out information-intensive tasks, such as debugging, refactoring, and reuse. In this talk, I present an evolutionary-ecolo...
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Software development is a human-centric activity. Developers often spend valuable time carrying out information-intensive tasks, such as debugging, refactoring, and reuse. In this talk, I present an evolutionary-ecological understanding about how developers seek and collect relevant information in software engineering. The basic idea is to model developers as predators in pursuit of prey(the relevant information), and to leverage the optimal food-foraging principles to characterize a rational decision-making process. In this way, the optimal developer's behavior can be mathematically formalized in light of the "built-in" mechanisms that evolved to help our animal ancestors to find food. I then describe two empirical studies on software traceability to apply the foraging-theoretic framework. The first study compares the behavior of real developers with that of the optimal information forager. The results show that the developers' information diets are significantly wider than the theory's predictions, and their residing in low-profitability information patches is significantly longer than the optimal residence time. The uncovered departures from optimality offer concrete insights into the obstacles faced by the developers. This in turn leads to the second study which employs clustering as a principled way to overcome the obstacles. I conclude the talk by sharing my vision for new research directions aimed at enabling developers to best shape themselves to their information and task environments, as well as enabling the environments to be best shaped to software developers.
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