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81.
A technique to improve the adaptation transient in discrete-time model reference adaptive control (MRAC) systems is given on the basis of applying classical optimization techniques to an equivalent near-linear system to the whole adaptive scheme. The resulting optimization is finally translated into modifications of one of the parameters entering the adaptation algorithm. This permits computation of a posteriori values of the adaptive controller parameters before generation of the input to the plant.  相似文献   
82.
In last years, Face recognition based on 3D techniques is an emergent technology which has demonstrated better results than conventional 2D approaches. Using texture (180° multi-view image) and depth maps is supposed to increase the robustness towards the two main challenges in Face Recognition: Pose and illumination. Nevertheless, 3D data should be acquired under highly controlled conditions and in most cases depends on the collaboration of the subject to be recognized. Thus, in applications such as surveillance or control access points, this kind of 3D data may not be available during the recognition process. This leads to a new paradigm using some mixed 2D-3D face recognition systems where 3D data is used in the training but either 2D or 3D information can be used in the recognition depending on the scenario. Following this concept, where only part of the information (partial concept) is used in the recognition, a novel method is presented in this work. This has been called Partial Principal Component Analysis (P2CA) since they fuse the Partial concept with the fundamentals of the well known PCA algorithm. This strategy has been proven to be very robust in pose variation scenarios showing that the 3D training process retains all the spatial information of the face while the 2D picture effectively recovers the face information from the available data. Furthermore, in this work, a novel approach for the automatic creation of 180° aligned cylindrical projected face images using nine different views is presented. These face images are created by using a cylindrical approximation for the real object surface. The alignment is done by applying first a global 2D affine transformation of the image, and afterward a local transformation of the desired face features using a triangle mesh. This local alignment allows a closer look to the feature properties and not the differences. Finally, these aligned face images are used for training a pose invariant face recognition approach (P2CA).  相似文献   
83.
刘德  汪德潢 《微计算机信息》2007,23(32):264-266
专家系统是人工智能的一个分支,是一种模拟专家决策能力的计算机系统,知识库是系统的重要组成部分,是系统的核心。本文结合纺织工艺设计及管理专家系统介绍了基于知识的专家系统的概念和结构,对系统中知识的获取、存储方式予以说明.并对其知识的表示方法加以阐述。  相似文献   
84.
MPLS(Multi-Protocol Label Switch)和服务质量(QoS)是与下一代网络相关的重要技术.作者首先介绍了QoS的两种模型:综合服务(IntServ)和区分服务(DiffServ)模型,然后描述了基于MPLS网络的DiffServ模型的实现.文中介绍了网络电视(IPTV)系统的组成和存在的问题,并提出了一个基于MPLS的QoS区分服务模型改进方案.  相似文献   
85.
Cookies enriched with 0, 5, 10, 15, 20, and 25% full-fat sweet lupine flour (FFSL) were evaluated by a sensory panel using the rank of preference and paired comparison tests. Cookies with 0, 5, and 10% FFSL were preferred while those containing 20 and 25% FFSL were rejected (p≤0.01). Studies conducted with school children showed similar acceptability for 0 and 10% FFSL-containing cookies which was different (p = 0.05) from those containing 20% FFSL. Fortification of the basic formula with 10% FFSL was recommended on the basis of acceptability.  相似文献   
86.
Counting Objects   总被引:1,自引:0,他引:1  
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87.
A mobile robot needs to know its position and orientation with accuracy in order to decide the control actions that permit it to finish the entrusted tasks successfully. To obtain this information, dead-reckoning-based systems have been used, and more recently inertial navigation systems. However, these systems have some errors that grow bigger as time goes by, therefore a moment comes when the information provided is useless. Because of this, there should be a periodic process that updates the robot position and orientation of the vehicle. The process to determine the robot position and orientation by using information originated from the external sensors is defined as the mobile robot relocalization. It is obvious that the greater the frequency of this process, the better the knowledge of its position the robot will have, and therefore its movements will be better directed to the point it must reach. The algorithm to achieve this can be classified in two large groups: relocalization through an a priori map of the environment and relocalization through the detection of landmarks present in that environment. The algorithm presented in the paper belongs to the first case. The sensor used is a combination of a laser diode and a CCD camera. The sensorial information is modelled as straight lines that will be matched with an a priori map of the environment. With this, the position of the mobile robot is estimated. The matching process is accomplished within an extended Kalman filter. The algorithm is able to work in real time, and it actualizes the position of the robot in a continuous way.  相似文献   
88.
OBJECTIVE: To describe the steps pharmacists must complete when seeking compensation from third party payers for pharmaceutical care services. DATA SOURCES: Government publications; professional publications, including manuals and newsletters; authors' personal experience. DATA SYNTHESIS: Pharmacists in increasing numbers are meeting with success in getting reimbursed by third party payers for patient care activities. However, many pharmacists remain reluctant to seek compensation because they do not understand the steps involved. Preparatory steps include obtaining a provider/supplier number, procuring appropriate claim forms, developing data collection and documentation systems, establishing professional fees, creating a marketing plan, and developing an accounting system. To bill for specific patient care services, pharmacists need to collect the patient's insurance information, obtain a statement of medical necessity from the patient's physician, complete the appropriate claim form accurately, and submit the claim with supporting documentation to the insurer. Although many claims from pharmacists are rejected initially, pharmacists who work with third party payers to understand the reasons for denial of payment often receive compensation when claims are resubmitted. CONCLUSION: Pharmacists who follow these guidelines for billing third party payers for pharmaceutical care services should notice an increase in the number of paid claims.  相似文献   
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