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Evolutionary design of photometric systems and its application to Gaia  [PDF]
C. A. L. Bailer-Jones
Computer Science , 2004, DOI: 10.1051/0004-6361:20035779
Abstract: Designing a photometric system to best fulfil a set of scientific goals is a complex task, demanding a compromise between conflicting requirements and subject to various constraints. A specific example is the determination of stellar astrophysical parameters (APs) - effective temperature, metallicity etc. - across a wide range of stellar types. I present a novel approach to this problem which makes minimal assumptions about the required filter system. By considering a filter system as a set of free parameters it may be designed by optimizing some figure-of-merit (FoM) with respect to these parameters. In the example considered, the FoM is a measure of how well the filter system can `separate' stars with different APs. This separation is vectorial in nature, in the sense that the local directions of AP variance are preferably mutually orthogonal to avoid AP degeneracy. The optimization is carried out with an evolutionary algorithm, which uses principles of evolutionary biology to search the parameter space. This model, HFD (Heuristic Filter Design), is applied to the design of photometric systems for the Gaia space astrometry mission. The optimized systems show a number of interesting features, not least the persistence of broad, overlapping filters. These HFD systems perform as least as well as other proposed systems for Gaia, although inadequacies remain in all. The principles underlying HFD are quite generic and may be applied to filter design for numerous other projects, such as the search for specific types of objects or photometric redshift determination.
Inverse lattice design and its application to bent waveguides  [PDF]
E. Rivera-Moci?os,E. Sadurní
Physics , 2015,
Abstract: This paper is divided in two parts. In the first part, the inverse spectral problem for tight-binding hamiltonians is studied. This problem is shown to have an infinite number of solutions for properly chosen energies. The space of such solutions is characterized by a hypersurface in the space of hopping amplitudes (i.e. couplings), whose dimension is half the number of sites in the array. Low dimensional examples for short chains are carefully studied and a table of exactly solvable inverse problems is provided in terms of Lie algebraic structures. With the aim of providing a method to generate lattice configurations, a set of equations for coupling constants in terms of energies is obtained; this is done by means of a new formula for the calculation of characteristic polynomials. Two examples with randomly generated spectra are studied numerically, leading to peaked distributions of couplings. In the second part of the paper, our results are applied to the design of bent waveguides, reproducing specific spectra below propagation threshold. As a demonstration, the Dirac and the finite oscillator are realized in this way. A few partially isospectral configurations are also presented.
Peer-to-Peer Live Streaming and Video On Demand Design Issues and its Challenges  [PDF]
Hareesh. K,Manjaiah D. H
Computer Science , 2011, DOI: 10.5121/ijp2p.2011.2401
Abstract: Peer-to-Peer Live streaming and Video on Demand is the most popular media applications over the Internet in recent years. These systems reduce the load on the server and provide a scalable content distribution. A new paradigm of P2P network collaborates to build large distributed video applications on existing networks .But, the problem of designing the system are at par with the P2P media streaming, live and Video on demand systems. Hence a comprehensive design comparison is needed to build such kind of system architecture. Therefore, in this paper we elaborately studied the traditional approaches for P2P streaming architectures, and its critical design issues, as well as practicable challenges. Thus, our studies in this paper clearly point the tangible design issues and its challenges, and other intangible issues for providing P2P VoD services.
Design of environmental decision support system and its application to water quality management
Zeng Fan-tang,Du Ling,Lin Kui,Shen Qian,
ZENG Fan-tang
,DU Ling,LIN Kui,SHEN Qian

地理学报(英文版) , 2001,
Abstract: EDSS is a comprehensive software system for water quality management in tidal river networks in general and for the Pearl River Delta in particular. Its purpose is to provide a practical tool that could assist government agencies in decision making for the efficient management of water resources in terms of both quantity and quality. By combining the capabilities of geographical information system (GIS), database management system (DBMS), model base management system (MBMS) and expert system, the aim is to improve the quality of decision making in what is becoming an increasingly complex area. This paper first outlines the basic concepts and philosophy adopted in developing EDSS, the system architecture, design features, implementation techniques and facilities provided. Thereafter, the core part of the system-the hydrodynamic and water quality models are described briefly. The final contribution in this paper describes the application of EDSS to the Pearl River Delta, which has the most complicated tidal river network patterns as well as the fastest economic development in the world. Examples are given of the real-world problems that can be addressed using the system, including cross-boundary water pollution analysis, regional drinking water take-up site selection, screening of important polluters, environmental impact assessment, and water quality zoning and planning. It is illustrated that EDSS can provide efficient and scientific analytical tools for planning and decision-making purposes in the information era.
Design of an interactive game-based application for improving the resolution of common Computer Network issues  [PDF]
Mario Ciau Uitzil,Lizzie Narvandaacute;ez Dandiacute;az,Victor Chi Pech
International Journal of Computer Science Issues , 2012,
Abstract: The need to find new ways to help students in the learning process makes us more involved with technology which evolves every day. This background leads us to find new methods and forms of teaching that help students accelerate their learning skills in a different way from the traditional, as in the case of learning through play, a concept that has been used in many games which have had great impact recently, becoming an innovative tool for learning. This paper shows the design of an interactive game-based application developed with Blender 2.49b tool to be implemented in the area of computer networks.
Design Issues in Aspect Oriented Programming  [PDF]
Deepak Dahiya,Rajinder K. Sachdeva
Information Technology Journal , 2007,
Abstract: The actual realization of a design language form has been revealed to be non-trivial. Most of the design languages are very much tailored towards a specific application or application domain. Moreover, with the exception of very few hardly any of these language notations have been used outside their own research environment. The development of a more generic aspect oriented design language requires a wider and more thorough look at the requirements. This study examines the design notation issues and discusses how it fulfils the requirements in principle and design and consequently would lead to a general purpose AOSD design language (AOSDDL) that will map AOSD design notations to the existing AOP languages.
A Novel Window and Its Application in NPR Type Transmultiplexer Design
Electrical and Electronic Engineering , 2012, DOI: 10.5923/j.eee.20120206.01
Abstract: This paper proposes a new window based approach for the design of M-channel maximally decimated Near-Perfect Reconstruction (NPR) type transmultiplexer. Cosine modulation is used to design the synthesis and analysis sections of the transmultiplexer. The prototype filter is designed with high Side-Lobe-Fall-Off-Rate (SLFOR) combinational window functions. A gradient based optimization algorithm has been applied to minimize the interference parameters like Inter-Channel Interference (ICI) and Inter-Symbol Interference (ISI).The proposed method of design of transmultiplexers are showing the improvements in terms ICI and ISI.
Model-based analysis of oligonucleotide arrays: model validation, design issues and standard error application
Cheng Li, Wing Hung Wong
Genome Biology , 2001, DOI: 10.1186/gb-2001-2-8-research0032
Abstract: Probe-sensitivity indexes are stable across tissue types. The target gene's presence in many arrays of an array set allows the probe-sensitivity index to be estimated accurately. We extended the model to obtain expression values for PM-only arrays, and found that the 20-probe PM-only model is comparable to the 10-probe PM/MM difference model, in terms of the expression correlations with the original 20-probe PM/MM difference model. MBEI method is able to extend the reliable detection limit of expression to a lower mRNA concentration. The standard errors of MBEI can be used to construct confidence intervals of fold changes, and the lower confidence bound of fold change is a better ranking statistic for filtering genes. We can assign reliability indexes for genes in a specific cluster of interest in hierarchical clustering by resampling clustering trees. A software dChip implementing many of these analysis methods is made available.The model-based approach reduces the variability of low expression estimates, and provides a natural method of calculating expression values for PM-only arrays. The standard errors attached to expression values can be used to assess the reliability of downstream analysis.The statistical model proposed in [1] for one probe set in multiple oligonucleotide arrays has the form?????? (1)It states that the perfect match (PM)/mismatch (MM) difference in array i, probe j of this probe set is the product of model-based expression index (MBEI) in array i (θi) and probe-sensitivity index of probe j (j) plus random error. Here J is the number of probe pairs in the probe set. Fitting the model, we can identify cross-hybridizing probes (j with large standard error (SE), which are excluded during iterative fitting) and arrays with image contamination at this probe set (θi with large SE), as well as single outliers (image spikes) which are replaced by the fitted values. In effect the estimated expression index θi is a weighted average of PM/MM differences:
A new design of groundwater sampling device and its application
Yih-Jin Tsai,Ming-Ching TKuo,
Yih-Jin Tsai
,Ming-Ching T. Kuo

环境科学学报(英文版) , 2005,
Abstract: Compounds in the atmosphere contaminate samples of groundwater. An inexpensive and simple method for collecting groundwater samples is developed to prevent contamination when the background concentration of contaminants is high. This new design of groundwater sampling device involves a glass sampling bottle with a Teflon-lined valve at each end. A cleaned and dried sampling bottle was connected to a low flow-rate peristaltic pump with Teflon tubing and was filled with water. No headspace volume was remained in the sampling bottle. The sample bottle was then packed in a PVC bag to prevent the target component from infiltrating into the water sample through the valves. In this study, groundwater was sampled at six wells using both the conventional method and the improved method. The analysis of trichlorofluoromethane(CFC-11) concentrations at these six wells indicates that all the groundwater samples obtained by the conventional sampling method were contaminated by CFC-11 from the atmosphere. The improved sampling method greatly eliminated the problems of contamination, preservation and quantitative analysis of natural water.
Competitive Algorithm of Simulating Natural Tree Growth and its Application in Antenna Design
Bo Lu;Junjun Zhang;Ka-Ma Huang
PIER Letters , 2009, DOI: 10.2528/PIERL09082402
Abstract: A novel Competitive Algorithm of Simulating Natural Tree Growth is presented in this paper. It searches from a simple status to complex ones and is characterized by quick convergence. The algorithm has been used to design a novel tree-shaped antenna which has an appreciably larger gain of 2\,dBi more than traditional dipole antenna with a reflector of the same size. A prototype antenna has been fabricated and tested. A good agreement between the calculated and measured results verifies the feasibility of the algorithm.
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