A new geometric approach to blind source separation of bounded sources

Based on the minimum-range approach, a new geometric approach is proposed to deal with blind source separation in this paper. The new approach is the batch mode of the original minimum-range approach. Compared with the original approach, the optimization algorithm of the proposed approach needs no parameters and is more efficient and reliable. In addition, the extension of minimum-rangebased approaches is discussed. The simulations show the efficiency of the proposed approach.     

SH-guided waves in layered piezoelectric/piezomagnetic plates

The propagation of shear horizontal (SH) guided waves in a coupled plate consisting of a piezoelectric layer and a piezomagnetic layer is studied. Both the layers are transversely isotropic and perfectly bonded along the interface. The upper and the lower surfaces of the plate are assumed to be mechanically free, electrically open and magnetically closed. Two different cases are considered. One is that the bulk shear wave velocity of piezoelectric material is larger than that of piezomagnetic material. The other is that the bulk shear wave velocity of piezomagnetic material is larger than that of piezoelectric material. The dispersion relation is obtained while the phase velocity is among the bulk shear wave velocity of two different layers. The numerical results show that the phase velocity approaches the smaller bulk shear wave velocity of the material in the system with the increase in the wave number for different modes. The thickness ratio and the properties of the piezoelectric material have great effect on the dispersion behaviors. The results of this paper can offer some fundamental theory to the application of piezoelectric/piezomagnetic composites or structures.     

Advanced technology for functionalization of carbon nanotubes

Functionalization of carbon nanotubes (CNTs) has attracted considerable interest in the fields of physics, chemistry, material science and biology. The functionalized CNTs exhibit improved properties enabling facile fabrication of novel nanomaterials and nanodevices. Most of the functionalization approaches developed at present could be categorized into the covalent attachment of functional groups and the non-covalent adsorption of various functional molecules onto the surface of CNTs. This review highlights recent development and our work in functionalization of carbon nanotubes, leading to bio-compatible CNTs, fluorescent CNTs and transition metal functionalized CNTs. These novel methods possess advantages such as simplified technical procedures and reduced cost of novel nanomaterials and nanodevices fabrication.     

Deterministic learning from control of nonlinear systems with disturbances

In this paper, we investigate deterministic learning in environments with disturbances. We will show that for a class of uncertain nonlinear systems with bounded disturbances, by using an appropriately designed adaptive neural controller, the disturbances are attenuated and the system output tracks a periodic orbit in finite time. As radial basis function (RBF) neural networks (NN) are employed, this leads to the satisfaction of a partial persistence of the excitation (PE) condition. By using the uniform complete observability (UCO) technique, it is analyzed that partial estimated NN weights will converge to a neighborhood of zero, with the size of the neighborhood depending on the amplitude of disturbances as well as on the control gains. Locally-accurate approximation of unknown system dynamics can still be achieved in the stable NN control process. The approximation error level is influenced by the amplitude of disturbances. The obtained knowledge of system dynamics can be reused in another control process towards stability and improved performance. Simulation studies are included to demonstrate the effectiveness of the approach.     

《粒子群算法及应用》

著者:纪震廖惠连吴青华书号:978-7-03-023284-3出版:科学出版社2009年1月定价:48元粒子群算法是一种新的模仿鸟类群体行为的智能优化     

科学出版社期刊出版中心招聘启事

科学出版社期刊出版中心是专业化科技期刊出版服务机构,致力于打造中国科技期刊的集团军,做大做强科技期刊产业.现因业务发展需要,招聘以下岗位:1.编辑人员5名,其中出版管理编辑1人,医学专业编辑3人(医学中文编辑2人、医学英文编辑1人),工程技     

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《Journal of Bionics Engineering》(仿生工程学报)简介

《Journal of Bionics Engineering》是由国家新闻出版总署批准，于2004年创刊的以工程仿生学科为特色的国际性英文学术期刊。本刊由教育部主管，吉林大学主办，科学出版社出版。办刊宗旨是及时报道国内外仿生学科领域最新的、具有创新性的优秀科研成果，为促进仿生学研究成果转化为生产力，加速该新兴、交叉、边缘学科实现跨越式、突破性发展服务。     

《大理学院学报》入选核心期刊

2011年8月,科学出版社出版了由中国科学评价研究中心、武汉大学图书馆和中国科教评价网研发的"中国学术期刊评价研究报告",该报告以"中国内地出版的中文学术期刊"为评价对象,采用得分排序和划分等级相结合的方法,将6400     

Protochordate amphioxus is an emerging model organism for comparative immunology

Protochordate amphioxus is an extant invertebrate regarded quite recently as a basal chordate. It has a vertebrate-like body plan including a circulation system with an organization similar to that of vertebrates. However, amphioxus is less complex than vertebrates for having a genome uncomplicated by extensive genomic duplication, and lacking lymphoid organs and free circulating blood cells. Recent studies on immunity have demonstrated the presence in amphioxus of both the constituent elements of key molecules involved in adaptive immunity such as proto-major histocompatibility complex (proto-MHC), V region-containing chitin-binding protein (VCBP) and V and C domain-bearing protein (VCP), and the complement system operating via the alternative and lectin pathways resembling those seen in vertebrates. In addition, the acute phase response profile in amphioxus has been shown to be similar to that observed in vertebrates. These findings together with the relative structural and genomic simplicity make amphioxus an ideal organism for gaining insights into the origin and evolution of the vertebrate immune system, especially adaptive immunity, and the composition and mechanisms of the vertebrate innate immunity.