Efficient Raw Signal Generation Based on Equivalent Scatterer and Subaperture Processing for SAR with Arbitrary Motion

An efficient SAR raw signal generation method based on equivalent scatterer and subaperture processing is proposed in this paper. It considers the radar’s motion track, which can obtain the precise raw signal for the real SAR. First, the imaging geometry with arbitrary motion is established, and then the scene is divided into several equidistant rings. Based on the equivalent scatterer model, the approximate expression of the SAR system transfer function is derived, thus each pulse’s raw signal can be generated by the convolution of the transmitted signal and system transfer function, performed by the fast Fourier transform (FFT). To further improve the simulation efficiency, the subaperture and polar subscene processing is used. The system transfer function of pluses for the same subaperture is calculated simultaneously by the weighted sum of all subscenes’ equivalent backscattering coefficient in the same equidistant ring, performed by the nonuniform FFT (NUFFT). The method only involves the FFT, NUFFT and complex multiplication operations, which means the easier implementation and higher efficiency. Simulation results are given to prove the validity of this method

Developing and applying an integrated modular design methodology within a SME

Modularity within a product can bring advantages to the design process by facilitating enhanced design reuse, reduced lead times, decreased cost and higher levels of quality. While the benefits of modularity are becoming increasingly better known, at present it is usually left to the designers themselves to introduce modularity into products. Studies into modularity have shown that byimplementing 'formal' methods, further benefits can be made in terms of time, cost, quality and performance. Current approaches that have been proposed for the formal development of modular design methodologies fail to accurately represent knowledge that is inherently produced during design projects and fail to consider design from the different viewpoints of the development process. This work, built on previous work on modularity and design for reuse, aims to develop an integrated design methodology that will optimise the modules created through the design process and allow for modularity to be 'built-in' to product development from the initial stages. The methodology andassociated tools have been developed to provide an easy-to-use approach to modularity that has support for design rationales and company knowledge that aid in effective design decision making. The methodology, named GeMoCURE, provides an integrated total solution to modular design based on reuse of proven physical and knowledge modules. Its incremental nature allows for the optimalstructure to be maintained as the design progresses. A special focus has been on the application of this approach for Small to Medium Enterprises (SMEs), which are typically challenged by a lack of design human resources and expertise

Validation of purdue engineering shape benchmark clusters by crowdsourcing

The effective organization of CAD data archives is central to PLM and consequently content based retrieval of 2D drawings and 3D models is often seen as a "holy grail" for the industry. Given this context, it is not surprising that the vision of a "Google for shape", which enables engineers to search databases of 3D models for components similar in shape to a query part, has motivated numerous researchers to investigate algorithms for computing geometric similarity. Measuring the effectiveness of the many approaches proposed has in turn lead to the creation of benchmark datasets against which researchers can compare the performance of their search engines. However to be useful the datasets used to measure the effectiveness of 3D retrieval algorithms must not only define a collection of models, but also provide a canonical specification of their relative similarity. Because the objective of shape retrieval algorithms is (typically) to retrieve groups of objects that humans perceive as "similar" these benchmark similarity relationships have (by definition) to be manually determined through inspection

Environmental Policy Analysis for Water Management in Lanzhou City

AbstractHuman activities significantly influence the integrality of ecosystems.Water plays a crucial role in ecosystems.In the last two decades,due to the over development of Lanzhou City,water environment becomes serious which is not compliance with the policy of sustainable development required by the local government.The existing policies and regulations related to water management in Lanzhou City is re-visited first in this paper.This includes the analysis of surface water and groundwater, investigation of current policies and regulations used for water management and their effects on water quality change, identification of the current problems resulting in water deterioration. Once the weaknesses of current environmental policies and regulations are figured out, they will be used to development of a comprehensive management system from the point of views engineering,legislative and social science.Finally nine corresponding implementation and management strategies based on this research are presented and will be reported to the local government

Geometric reasoning via internet crowdsourcing

The ability to interpret and reason about shapes is a peculiarly human capability that has proven difficult to reproduce algorithmically. So despite the fact that geometric modeling technology has made significant advances in the representation, display and modification of shapes, there have only been incremental advances in geometric reasoning. For example, although today's CAD systems can confidently identify isolated cylindrical holes, they struggle with more ambiguous tasks such as the identification of partial symmetries or similarities in arbitrary geometries. Even well defined problems such as 2D shape nesting or 3D packing generally resist elegant solution and rely instead on brute force explorations of a subset of the many possible solutions. Identifying economic ways to solving such problems would result in significant productivity gains across a wide range of industrial applications. The authors hypothesize that Internet Crowdsourcing might provide a pragmatic way of removing many geometric reasoning bottlenecks.This paper reports the results of experiments conducted with Amazon's mTurk site and designed to determine the feasibility of using Internet Crowdsourcing to carry out geometric reasoning tasks as well as establish some benchmark data for the quality, speed and costs of using this approach.After describing the general architecture and terminology of the mTurk Crowdsourcing system, the paper details the implementation and results of the following three investigations; 1) the identification of "Canonical" viewpoints for individual shapes, 2) the quantification of "similarity" relationships with-in collections of 3D models and 3) the efficient packing of 2D Strips into rectangular areas. The paper concludes with a discussion of the possibilities and limitations of the approach

Applications of nanometre scale particles as pharmaceutical delivery vehicles in medicine

Recent scientific advances have resulted in the emergence of the rapidly developing field of nanotechnology, which involves the rational design of materials and devices in the 1-100 nm range. At the nanometre scale, size, shape and surface morphology can have a profound influence on the chemical, physical, optical and electronic properties of a material, which is significantly different from their bulk counterparts. The novel size dependent properties at the nanometre scale, gives these materials their unique physiochemical properties, which have the potential to be used in a wide variety of applications. Nanomedicine is the term used to describe the use of nanotechnology in medicine, and includes its use in the development of diagnostic techniques and interventions, pharmaceuticals, regenerative medicine and tissue engineering. This brief review gives an overview of current developments in the use of nanometre scale particles that are specifically designed for the delivery of pharmaceuticals in medicine

Clinical characteristics and management of retinitis pigmentosa

Retinitis pigmentosa is a collective term for a group of inherited retinal dystrophies characterized by loss of rod photoreceptors, followed by loss of cone photoreceptors. It is a disease with a variable clinical and genetic presentation, with regards to age at onset, severity, and disease progression. For many patients, no treatment is available at the moment, but promising advances are made in genomic medicine. In preparation for these novel therapies, this thesis focuses on the clinical characteristics and natural course of candidate genes, in order to define optimal clinical endpoints. Additionally, this thesis investigates current treatment modalities, as retinitis pigmentosa is associated with ocular comorbidities such as cataract and cystoid macular edema, which can significantly impact a patient's quality of life when left untreated.The research presented in this thesis was financially supported by Algemene Nederlandse Vereniging ter Voorkoming van Blindheid (ANVVB), Landelijke Stichting voor Blinden en Slechtzienden (LSBS), and the Oogfonds, which contributed through UitZicht (Delft, the Netherlands); as well as the Curing Retinal Blindness Foundation, Stichting Blindenhulp, Bontius Stichting, and Retina Fonds. Financial support for the printing of this thesis was kindly provided by Chipsoft, D.O.R.C., Landelijke Stichting voor Blinden en Slechtzienden, Medical Workshop BV, Oculenti Contactlenspraktijken, Revoir/Ergra Low vision, Santen Pharmaceutical, Stichting Blindenhulp, Stichting Leids Oogheelkundig Ondersteuningsfonds, Synda Medical, Théa Pharma BV, Universitaire Bibliotheken Leiden.LUMC / Geneeskund

Emulation of modular manufacturing machines

A method for geometrically modelling and emulating modular machines based on the Universal Machine Control reference architecture is described. Geometric modelling is achieved through extensions to a proprietary robot simulation system. A library of modules consisting of 1, 2 or 3 degree of freedom manipulators is used to construct models of multi-degree of freedom distributed machines with appropriate kinematic characteristics. Logging of data from the real or emulated control handlers is then used to drive the geometric model. A case study of a printed circuit board assembly machine is used to demonstrate how this approach allows the investigation of machine performance before and during the building of the machine with real hardware elements

An intelligent task programming system for modular manufacturing machines

Modular manufacturing machines characterised by their configuration flexibility and low initial investment have increasingly gained more recognition as one of the flexible and responsive manufacturing machinery in current competitive manufacturing industry. Programming of a modular machine is a very important part of an entire machine design and simulation environment. This paper focuses on the programming issue of a modular machine design and simulation environment. A programming study is made of the features of modular machines in manufacturing, and a general systematic approach towards high level utilisation and control of modular machines is outlined. A three-level machine task programming approach within the simulation environment is described and finally an example task program and its execution in simulation environment is illustrated to demonstrate the system capability

Electrochemical synthesis, characterisation, and preliminary biological evaluation of an anodic aluminium oxide membrane with a pore size of 100 nanometres for a Potential Cell Culture Substrate

In this study we investigate the electrochemical synthesis and characterisation of a nanometre scale porous anodic aluminium oxide (AAO) membranes with a mean pore diameter of 100 nm. The membranes exhibit interesting properties such as controllable pore diameters, periodicity and density distribution. These properties can be preselected by adjusting the controlling parameters of a temperature controlled two-step anodization process. The surface features of the nanometre scale membrane such as pore density, pore diameter and inter-pore distance were quantified using field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). A preliminary biological evaluation of the membranes was carried out to determine cell adhesion and morphology using the Cercopithecus aethiops[African green monkey – (Vero)] kidney epithelial cell line. Optical microscopy, FESEM and AFM investigations revealed the presence of focal adhesion sites over the surface of the porous membranes. The positive outcomes of the study, indicates that AAO membranes can be used as a viable tissue scaffold for potential tissue engineering applications in the future