A computational fluid dynamics simulation of the hypersonic flight of the Pegasus(TM) vehicle using an artificial viscosity model and a nonlinear filtering method. M.S. Thesis

Science.gov (United States)

Mendoza, John Cadiz

1995-01-01

The computational fluid dynamics code, PARC3D, is tested to see if its use of non-physical artificial dissipation affects the accuracy of its results. This is accomplished by simulating a shock-laminar boundary layer interaction and several hypersonic flight conditions of the Pegasus(TM) launch vehicle using full artificial dissipation, low artificial dissipation, and the Engquist filter. Before the filter is applied to the PARC3D code, it is validated in one-dimensional and two-dimensional form in a MacCormack scheme against the Riemann and convergent duct problem. For this explicit scheme, the filter shows great improvements in accuracy and computational time as opposed to the nonfiltered solutions. However, for the implicit PARC3D code it is found that the best estimate of the Pegasus experimental heat fluxes and surface pressures is the simulation utilizing low artificial dissipation and no filter. The filter does improve accuracy over the artificially dissipative case but at a computational expense greater than that achieved by the low artificial dissipation case which has no computational time penalty and shows better results. For the shock-boundary layer simulation, the filter does well in terms of accuracy for a strong impingement shock but not as well for weaker shock strengths. Furthermore, for the latter problem the filter reduces the required computational time to convergence by 18.7 percent.

A planar and tunable bandpass filter on a ferrite substrate with integrated windings

KAUST Repository

Arabi, Eyad A.

2015-05-01

Tunable Filters that are based on ferrite materials are often biased by external magnets or coils which are large and bulky. In this work a completely planar, CPW-based bandpass filter is presented with integrated windings. Due to these windings the size of the filter is only 26mm × 34mm × 0.38mm which is orders of magnitude smaller than the traditional designs with external windings. The filter is realized by electroplating of Copper over seed layers of Titanium and Gold over a YIG substrate. The fabricated filter achieves a tunability of 3.4% without any external magnets or coils. A good insertion loss of 2.3 dBs and rejection greater than 50 dBs have been obtained. To the best of the authors knowledge, this design is the first ferrite-based design that is completely planar and self-biased.

Influence of substrates, light, filter paper and pH on the sporulation of Cercospora sojina

Directory of Open Access Journals (Sweden)

Diana Erica Gómez

2013-06-01

Full Text Available Fungi require special substrates for their isolation, vegetative growth and sporulation. In experiments conducted in the laboratory, the influence of substrates, light, filter paper and pH on the sporulation of Cercospora sojina conidia, the causal agent of soybean frogeye leaf spot, was assessed. The media potato sucrose agar, V-8 agar, tomato extract agar, soybean leaf extract agar, soybean seed extract agar, soybean meal agar, soybean flour agar and wheat flour agar were tested, added on the surface, with and without filter paper and under two light regimes, with 12 h light at 25°± 2°C and in the dark. A triple factorial 8x2x2 (substrates x light/dark x with/without filter paper design with four replicates was used. V-8 agar medium was employed and the pH was adjusted with HCl 0.1N or NaOH 0.1N before autoclaving to the values: 3, 4, 5, 6, 7 and 8, and the pH of V-8 agar medium is 6.7. The evaluation was done on the seventh day of incubation. Data underwent regression analysis. Sporulation was maximized on the agar media V-8, seed extract, oat flour, tomato extract, and potato sucrose in the presence of filter paper and 12h light. On V-8 medium, maximal sporulation was obtained with pH 6.7.

Substrate Integrated Waveguide Cross-Coupling Filter with Multilayer Hexagonal Cavity

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B. Wu

2013-01-01

Full Text Available Hexagonal cavities and their applications to multilayer substrate integrated waveguide (SIW filters are presented. The hexagonal SIW cavity which can combine flexibility of rectangular one and performance of circular one is convenient for bandpass filter’s design. Three types of experimental configuration with the same central frequency of 10 GHz and bandwidth of 6%, including three-order and four-order cross-coupling topologies, are constructed and fabricated based on low temperature cofired ceramic (LTCC technology. Both theoretical and experimental results are presented.

Substrate Integrated Waveguide Cavity Filters: Miniaturization and New Materials for IoT Applications

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C. Tomassoni

2017-09-01

Full Text Available This paper presents an overview of the current research trends in the field of substrate integrated waveguide (SIW technology, with particular emphasis on the issues related to the emerging applications in the framework of the Internet of Things (IoT and the fifth generation of mobile communication (5G. More specifically, different techniques adopted to miniaturize SIW cavities are described, with the aim of reducing the footprint of SIW components and filters. Moreover, the use of innovative materials, like paper, textile and 3D printed dielectric substrates, is presented and discussed, and the implementation of ecofriendly, wearable, and fully 3D structures is illustrated.

Design of a Miniaturized X-Band Diplexer Based on Novel One-Third-Mode Substrate Integrated Resonator Filters

Science.gov (United States)

Zhang, Hao; Kang, Wei; Wu, Wen

2017-12-01

In this paper, a miniaturized diplexer designed with two novel one-third-mode substrate integrated resonator (OTMSIR) filters has been presented. The one-third triangular resonator cavity with two transmission zeros (TZs) and two transmission poles is investigated. TZs are implemented by taking cross couplings of lower order modes in this design. The diplexer is then obtained by integrating two different sizes of OTMSIR filters with a common T-junction structure. A X-band diplexer operating at 10 GHz and 11.5 GHz is designed on a substrate with a dielectric constant of 3.55 to verify the above design concept. This novel structure features more compact size, better transmission performance, higher out of band rejection and easier integration compared with other circuits. A good agreement is obtained between the simulations and the measured results.

Equivalent circuit analysis of terahertz metamaterial filters

KAUST Repository

Zhang, Xueqian

2011-01-01

An equivalent circuit model for the analysis and design of terahertz (THz) metamaterial filters is presented. The proposed model, derived based on LMC equivalent circuits, takes into account the detailed geometrical parameters and the presence of a dielectric substrate with the existing analytic expressions for self-inductance, mutual inductance, and capacitance. The model is in good agreement with the experimental measurements and full-wave simulations. Exploiting the circuit model has made it possible to predict accurately the resonance frequency of the proposed structures and thus, quick and accurate process of designing THz device from artificial metamaterials is offered. ©2011 Chinese Optics Letters.

Use of artificial substrate in pond culture of freshwater prawn (Macrobrachium rosenbergii: a new approach regarding growth performance and economic return

Directory of Open Access Journals (Sweden)

Dilshad Milky Tuly

2014-04-01

Full Text Available An experiment was conducted for six months to evaluate the effects of artificial substrates on the survival, growth and production of Macrobrachium rosenbergii juveniles. The treatment T1 contained locally available bamboo-made substrate both vertical and horizontal and treatment T2 received no substrate. Juvenile prawns (0.40±0.13 g were stocked at the rate of 19,760 prawns ha-1. The water quality parameters range such as temperature, pH and DO were 22.06-33.45°C, 7.70-8.40 and 4.75-6.15 mgl-1 respectively which was no significant difference (P0.05 than T2 (56.87%. The specific growth rate, food conversion ratio and protein efficiency ratio were 1.19 % and 1.14 %, 3.15 and 4.39, 0.98 and 0.71 in T1 and T2 respectively which were not significantly different (P0.05 than T2. Thus growth and survival of prawn juveniles improved in presence of artificial substrate which could be economically viable technique for the freshwater prawn culture.

Miniaturized bandpass filter using a meandered stepped-impedance resonator with a meandered-line stub-load on a GaAs substrate.

Science.gov (United States)

Chuluunbaatar, Z; Wang, C; Kim, N Y

2014-01-01

This paper reports a compact bandpass filter with improved skirt selectivity using integrated passive device fabrication technology on a GaAs substrate. The structure of the filter consists of electromagnetically coupled meandered-line symmetric stepped-impedance resonators. The strength of the coupling between the resonators is enhanced by using a meandered-line stub-load inside the resonators to improve the selectivity and miniaturize the size of the filter. In addition, the center frequency of the filter can be flexibly controlled by varying degrees of the capacitive coupling between resonator and stub-load. To verify the proposed concept, a protocol bandpass filter with center frequency of 6.53 GHz was designed, fabricated, and measured, with a return loss and insertion loss of 39.1 dB and 1.63 dB.

An artificial functional family filter in homolog searching in next-generation sequencing metagenomics.

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Ruofei Du

Full Text Available In functional metagenomics, BLAST homology search is a common method to classify metagenomic reads into protein/domain sequence families such as Clusters of Orthologous Groups of proteins (COGs in order to quantify the abundance of each COG in the community. The resulting functional profile of the community is then used in downstream analysis to correlate the change in abundance to environmental perturbation, clinical variation, and so on. However, the short read length coupled with next-generation sequencing technologies poses a barrier in this approach, essentially because similarity significance cannot be discerned by searching with short reads. Consequently, artificial functional families are produced, in which those with a large number of reads assigned decreases the accuracy of functional profile dramatically. There is no method available to address this problem. We intended to fill this gap in this paper. We revealed that BLAST similarity scores of homologues for short reads from COG protein members coding sequences are distributed differently from the scores of those derived elsewhere. We showed that, by choosing an appropriate score cut-off, we are able to filter out most artificial families and simultaneously to preserve sufficient information in order to build the functional profile. We also showed that, by incorporated application of BLAST and RPS-BLAST, some artificial families with large read counts can be further identified after the score cutoff filtration. Evaluated on three experimental metagenomic datasets with different coverages, we found that the proposed method is robust against read coverage and consistently outperforms the other E-value cutoff methods currently used in literatures.

The effect of substrate bias on titanium carbide/amorphous carbon nanocomposite films deposited by filtered cathodic vacuum arc

International Nuclear Information System (INIS)

Zhang, Xu; Liang, Hong; Wu, Zhenglong; Wu, Xiangying; Zhang, Huixing

2013-01-01

The titanium carbide/amorphous carbon nanocomposite films have been deposited on silicon substrate by filtered cathodic vacuum arc (FCVA) technology, the effects of substrate bias on composition, structures and mechanical properties of the films are studied by scanning electron spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy and nano-indentation. The results show that the Ti content, deposition rate and hardness at first increase and then decrease with increasing the substrate bias. Maximum hardness of the titanium carbide/amorphous carbon nanocomposite film is 51 Gpa prepared at −400 V. The hardness enhancement may be attributed to the compressive stress and the fraction of crystalline TiC phase due to ion bombardment

A Method of Effective Quarry Water Purifying Using Artificial Filtering Arrays

Science.gov (United States)

Tyulenev, M.; Garina, E.; Khoreshok, A.; Litvin, O.; Litvin, Y.; Maliukhina, E.

2017-01-01

The development of open pit mining in the large coal basins of Russia and other countries increases their negative impact on the environment. Along with the damage of land and air pollution by dust and combustion gases of blasting, coal pits have a significant negative impact on water resources. Polluted quarry water worsens the ecological situation on a much larger area than covered by air pollution and land damage. This significantly worsens the conditions of people living in cities and towns located near the coal pits, and complicates the subsequent restoration of the environment, irreversibly destroying the nature. Therefore, the research of quarry wastewater purifying is becoming an important mater for scholars of technical colleges and universities in the regions with developing open-pit mining. This paper describes the method of determining the basic parameters of the artificial filtering arrays formed on coal pits of Kuzbass (Western Siberia, Russia), and gives recommendations on its application.

Miniaturized Bandpass Filter Using a Meandered Stepped-Impedance Resonator with a Meandered-Line Stub-Load on a GaAs Substrate

Directory of Open Access Journals (Sweden)

Z. Chuluunbaatar

2014-01-01

Full Text Available This paper reports a compact bandpass filter with improved skirt selectivity using integrated passive device fabrication technology on a GaAs substrate. The structure of the filter consists of electromagnetically coupled meandered-line symmetric stepped-impedance resonators. The strength of the coupling between the resonators is enhanced by using a meandered-line stub-load inside the resonators to improve the selectivity and miniaturize the size of the filter. In addition, the center frequency of the filter can be flexibly controlled by varying degrees of the capacitive coupling between resonator and stub-load. To verify the proposed concept, a protocol bandpass filter with center frequency of 6.53 GHz was designed, fabricated, and measured, with a return loss and insertion loss of 39.1 dB and 1.63 dB.

Automatic system for radar echoes filtering based on textural features and artificial intelligence

Science.gov (United States)

Hedir, Mehdia; Haddad, Boualem

2017-10-01

Among the very popular Artificial Intelligence (AI) techniques, Artificial Neural Network (ANN) and Support Vector Machine (SVM) have been retained to process Ground Echoes (GE) on meteorological radar images taken from Setif (Algeria) and Bordeaux (France) with different climates and topologies. To achieve this task, AI techniques were associated with textural approaches. We used Gray Level Co-occurrence Matrix (GLCM) and Completed Local Binary Pattern (CLBP); both methods were largely used in image analysis. The obtained results show the efficiency of texture to preserve precipitations forecast on both sites with the accuracy of 98% on Bordeaux and 95% on Setif despite the AI technique used. 98% of GE are suppressed with SVM, this rate is outperforming ANN skills. CLBP approach associated to SVM eliminates 98% of GE and preserves precipitations forecast on Bordeaux site better than on Setif's, while it exhibits lower accuracy with ANN. SVM classifier is well adapted to the proposed application since the average filtering rate is 95-98% with texture and 92-93% with CLBP. These approaches allow removing Anomalous Propagations (APs) too with a better accuracy of 97.15% with texture and SVM. In fact, textural features associated to AI techniques are an efficient tool for incoherent radars to surpass spurious echoes.

Iron removal using an aerated granular filter

Energy Technology Data Exchange (ETDEWEB)

Cho, B.Y. [Dongguk University, Seoul (Republic of Korea). College of Engineering

2005-10-01

Laboratory scale experiments concerning iron removal from artificial raw water by an artificial filter using anthracite as filter media were conducted. The major findings were that iron oxidation and removal by an aerated filter is mainly a catalytic chemical reaction rather than a biological reaction. Further, iron removal does not perform effectively without aeration. Iron removal was very effective when the pH was weakly acidity. Iron oxide attached to the surface of the media is identified as ferrihydrite, which catalyzes the oxidation of iron as shown by Moessbauer spectra analysis.

Use of artificial substrates of different colors for oviposition by the brown stink bug Euschistus heros (Hemiptera, Pentatomidae

Directory of Open Access Journals (Sweden)

Diones Krinski

2013-09-01

Full Text Available Aiming to contribute to a rearing methodology for the brown stink bug, Euschistus heros, in the laboratory, we evaluated oviposition on artificial substrates of different colors. During six days, oviposition was evaluated daily, by counting the total number of eggs, number of clutches, and eggs/clutch. Females laid 12,463 eggs, in 1,677 clutches, resulting in an average of 7.28 ± 0.44 eggs/clutch. Black, brown, and green felt had the most eggs and clutches. The results demonstrated that many colors are suitable as oviposition substrate for E. heros, providing information for the mass rearing of this insect.

Development of an optimal filter substrate for the identification of small microplastic particles in food by micro-Raman spectroscopy.

Science.gov (United States)

Oßmann, Barbara E; Sarau, George; Schmitt, Sebastian W; Holtmannspötter, Heinrich; Christiansen, Silke H; Dicke, Wilhelm

2017-06-01

When analysing microplastics in food, due to toxicological reasons it is important to achieve clear identification of particles down to a size of at least 1 μm. One reliable, optical analytical technique allowing this is micro-Raman spectroscopy. After isolation of particles via filtration, analysis is typically performed directly on the filter surface. In order to obtain high qualitative Raman spectra, the material of the membrane filters should not show any interference in terms of background and Raman signals during spectrum acquisition. To facilitate the usage of automatic particle detection, membrane filters should also show specific optical properties. In this work, beside eight different, commercially available membrane filters, three newly designed metal-coated polycarbonate membrane filters were tested to fulfil these requirements. We found that aluminium-coated polycarbonate membrane filters had ideal characteristics as a substrate for micro-Raman spectroscopy. Its spectrum shows no or minimal interference with particle spectra, depending on the laser wavelength. Furthermore, automatic particle detection can be applied when analysing the filter surface under dark-field illumination. With this new membrane filter, analytics free of interference of microplastics down to a size of 1 μm becomes possible. Thus, an important size class of these contaminants can now be visualized and spectrally identified. Graphical abstract A newly developed aluminium coated polycarbonate membrane filter enables automatic particle detection and generation of high qualitative Raman spectra allowing identification of small microplastics.

Multifunctionality is affected by interactions between green roof plant species, substrate depth, and substrate type.

Science.gov (United States)

Dusza, Yann; Barot, Sébastien; Kraepiel, Yvan; Lata, Jean-Christophe; Abbadie, Luc; Raynaud, Xavier

2017-04-01

Green roofs provide ecosystem services through evapotranspiration and nutrient cycling that depend, among others, on plant species, substrate type, and substrate depth. However, no study has assessed thoroughly how interactions between these factors alter ecosystem functions and multifunctionality of green roofs. We simulated some green roof conditions in a pot experiment. We planted 20 plant species from 10 genera and five families (Asteraceae, Caryophyllaceae, Crassulaceae, Fabaceae, and Poaceae) on two substrate types (natural vs. artificial) and two substrate depths (10 cm vs. 30 cm). As indicators of major ecosystem functions, we measured aboveground and belowground biomasses, foliar nitrogen and carbon content, foliar transpiration, substrate water retention, and dissolved organic carbon and nitrates in leachates. Interactions between substrate type and depth strongly affected ecosystem functions. Biomass production was increased in the artificial substrate and deeper substrates, as was water retention in most cases. In contrast, dissolved organic carbon leaching was higher in the artificial substrates. Except for the Fabaceae species, nitrate leaching was reduced in deep, natural soils. The highest transpiration rates were associated with natural soils. All functions were modulated by plant families or species. Plant effects differed according to the observed function and the type and depth of the substrate. Fabaceae species grown on natural soils had the most noticeable patterns, allowing high biomass production and high water retention but also high nitrate leaching from deep pots. No single combination of factors enhanced simultaneously all studied ecosystem functions, highlighting that soil-plant interactions induce trade-offs between ecosystem functions. Substrate type and depth interactions are major drivers for green roof multifunctionality.

Assessment of benthic macroinvertebrates at Nile tilapia production using artificial substrate samplers

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M. S. G. Moura e Silva

Full Text Available Abstract Biomonitoring is a cheap and effective tool for evaluation of water quality, and infer on the balance of aquatic ecosystems. The benthic macroinvertebrates are bioindicators sensitive to environmental changes, and can assist in detecting and preventing impacts such as organic enrichment and imbalance in the food chain. We compared the structure of benthic communities on artificial substrate samplers located in places near and far from net cages for production of Nile tilapia (Oreochromis niloticus. Samplers were manufactured with nylon net, using substrates such as crushed stone, gravel, loofah and cattail leaves. Samples were collected after 30 days of colonization, rinsed and then the specimens were identified and quantified. The following metrics were calculated: richness of Operational Taxonomic Units, Margalef richness, abundance of individuals, Shannon index and evenness index. The macrobenthic community structure was strongly modified according to the proximity of the net cages. Metrics showed significant differences (p < 0.05 between near and distant sites, for both periods (dry and rainy seasons. The position of the samplers significantly affected the structure of macroinvertebrate community, as near sites showed higher values for the community metrics, such as richness and diversity. Near sites presented a larger number of individuals, observed both in the dry and rainy seasons, with a predominance of Chironomidae (Diptera in the dry season and Tubificidae (Oligochaeta in the rainy season.

The use of dried cerebrospinal fluid filter paper spots as a substrate for PCR diagnosis of the aetiology of bacterial meningitis in the Lao PDR

OpenAIRE

Elliott, I.; Dittrich, S.; Paris, D.; Sengduanphachanh, A.; Phoumin, P.; Newton, P.N.

2013-01-01

We investigated whether dried cerebrospinal fluid (CSF) conserved on filter paper can be used as a substrate for accurate PCR diagnosis of important causes of bacterial meningitis in the Lao PDR. Using mock CSF, we investigated and optimized filter paper varieties, paper punch sizes, elution volumes and quantities of DNA template to achieve sensitive and reliable detection of bacterial DNA from filter paper specimens. FTA Elute Micro Card? (Whatman, Maidstone, UK) was the most sensitive, cons...

Structural Dynamic Response Compressing Technique in Bridges using a Cochlea-inspired Artificial Filter Bank (CAFB)

International Nuclear Information System (INIS)

Heo, G; Jeon, J; Son, B; Kim, C; Jeon, S; Lee, C

2016-01-01

In this study, a cochlea-inspired artificial filter bank (CAFB) was developed to efficiently obtain dynamic response of a structure, and a dynamic response measurement of a cable-stayed bridge model was also carried out to evaluate the performance of the developed CAFB. The developed CAFB used a band-pass filter optimizing algorithm (BOA) and peakpicking algorithm (PPA) to select and compress dynamic response signal containing the modal information which was significant enough. The CAFB was then optimized about the El-Centro earthquake wave which was often used in the construction research, and the software implementation of CAFB was finally embedded in the unified structural management system (USMS). For the evaluation of the developed CAFB, a real time dynamic response experiment was performed on a cable-stayed bridge model, and the response of the cable-stayed bridge model was measured using both the traditional wired system and the developed CAFB-based USMS. The experiment results showed that the compressed dynamic response acquired by the CAFB-based USMS matched significantly with that of the traditional wired system while still carrying sufficient modal information of the cable-stayed bridge. (paper)

Artificial Fish Swarm Algorithm-Based Particle Filter for Li-Ion Battery Life Prediction

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Ye Tian

2014-01-01

Full Text Available An intelligent online prognostic approach is proposed for predicting the remaining useful life (RUL of lithium-ion (Li-ion batteries based on artificial fish swarm algorithm (AFSA and particle filter (PF, which is an integrated approach combining model-based method with data-driven method. The parameters, used in the empirical model which is based on the capacity fade trends of Li-ion batteries, are identified dependent on the tracking ability of PF. AFSA-PF aims to improve the performance of the basic PF. By driving the prior particles to the domain with high likelihood, AFSA-PF allows global optimization, prevents particle degeneracy, thereby improving particle distribution and increasing prediction accuracy and algorithm convergence. Data provided by NASA are used to verify this approach and compare it with basic PF and regularized PF. AFSA-PF is shown to be more accurate and precise.

Improving Artificial eural etwork Forecasts with Kalman Filtering

African Journals Online (AJOL)

Nafiisah

technique in financial time series and the application of a Kalman filter ... networks (ANN) model using a Kalman filter leads to significant improvements in .... 3-rd order polynomial (Galanis et al. (2006)): 1 t p. 2 t p. 3 t p. 4 t p. 1 t h. 2 t h tr t r ...

Artificial Neural Networks and Instructional Technology.

Science.gov (United States)

Carlson, Patricia A.

1991-01-01

Artificial neural networks (ANN), part of artificial intelligence, are discussed. Such networks are fed sample cases (training sets), learn how to recognize patterns in the sample data, and use this experience in handling new cases. Two cognitive roles for ANNs (intelligent filters and spreading, associative memories) are examined. Prototypes…

Supervised scale-regularized linear convolutionary filters

DEFF Research Database (Denmark)

Loog, Marco; Lauze, Francois Bernard

2017-01-01

also be solved relatively efficient. All in all, the idea is to properly control the scale of a trained filter, which we solve by introducing a specific regularization term into the overall objective function. We demonstrate, on an artificial filter learning problem, the capabil- ities of our basic...

Balanced microwave filters

CERN Document Server

Hong, Jiasheng; Medina, Francisco; Martiacuten, Ferran

2018-01-01

This book presents and discusses strategies for the design and implementation of common-mode suppressed balanced microwave filters, including, narrowband, wideband, and ultra-wideband filters This book examines differential-mode, or balanced, microwave filters by discussing several implementations of practical realizations of these passive components. Topics covered include selective mode suppression, designs based on distributed and semi-lumped approaches, multilayer technologies, defect ground structures, coupled resonators, metamaterials, interference techniques, and substrate integrated waveguides, among others. Divided into five parts, Balanced Microwave Filters begins with an introduction that presents the fundamentals of balanced lines, circuits, and networks. Part 2 covers balanced transmission lines with common-mode noise suppression, including several types of common-mode filters and the application of such filters to enhance common-mode suppression in balanced bandpass filters. Next, Part 3 exa...

Modelling substrate specificity and enantioselectivity for lipases and esterases by substrate-imprinted docking

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Tyagi Sadhna

2009-06-01

Full Text Available Abstract Background Previously, ways to adapt docking programs that were developed for modelling inhibitor-receptor interaction have been explored. Two main issues were discussed. First, when trying to model catalysis a reaction intermediate of the substrate is expected to provide more valid information than the ground state of the substrate. Second, the incorporation of protein flexibility is essential for reliable predictions. Results Here we present a predictive and robust method to model substrate specificity and enantioselectivity of lipases and esterases that uses reaction intermediates and incorporates protein flexibility. Substrate-imprinted docking starts with covalent docking of reaction intermediates, followed by geometry optimisation of the resulting enzyme-substrate complex. After a second round of docking the same substrate into the geometry-optimised structures, productive poses are identified by geometric filter criteria and ranked by their docking scores. Substrate-imprinted docking was applied in order to model (i enantioselectivity of Candida antarctica lipase B and a W104A mutant, (ii enantioselectivity and substrate specificity of Candida rugosa lipase and Burkholderia cepacia lipase, and (iii substrate specificity of an acetyl- and a butyrylcholine esterase toward the substrates acetyl- and butyrylcholine. Conclusion The experimentally observed differences in selectivity and specificity of the enzymes were reproduced with an accuracy of 81%. The method was robust toward small differences in initial structures (different crystallisation conditions or a co-crystallised ligand, although large displacements of catalytic residues often resulted in substrate poses that did not pass the geometric filter criteria.

A miniaturized Microwave Bandpass Filter Based on Modified (Mg0.95Ca0.05TiO3 Substrate

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Hu Mingzhe

2016-01-01

Full Text Available A microwave miniaturized bandpass filter using (Mg0.95Ca0.05TiO3 (abbreviated as 95MCT hereafter ceramic substrate is investigated in the present paper. The paper studies the sintering and microwave dielectric properties of Al2O3, La2O3 and SiO2 co-doped 95MCT. The XRD pattern shows that a secondary phase MgTi2O5 is easily segregated in 95MCT ceramic, however, through co-doping it can be effectively suppressed, and the microwave dielectric properties, especially, the Qf value can be significantly improved. Through optimizing the co-doping ratio of Al2O3, La2O3 and SiO2, the sintering temperature of 95MCT ceramic can be lowered by 80°C, and the microwave dielectric properties can reach Qf=61856GHz and εr=19.84, which indicates the modified 95MCT ceramic have a great potential application in microwave communication devices. Based on this, we also designed a miniaturized microwave bandpass filter (BPF on modified 95MCT substrate. Through a full wave electromagnetic structure simulation, the results show that the center frequency of the BPF is 2.45GHz and the relative bandwidth is 4.09% with the insertion loss of less than 0.2dB in the whole bandpass.

UV filters for lighting of plants

Energy Technology Data Exchange (ETDEWEB)

Doehring, T.; Koefferlein, M.; Thiel, S.; Seidlitz, H.K.; Payer, H.D. [GSF-Forschungszentrum fuer Umwelt und Gesundheit GmbH, Oberschleissheim (Germany)

1994-12-31

Different filter glasses are available which provide absorption properties suitable for gradual changes of the spectral UV-B illumination of artificial lighting. Using a distinct set of lamps and filter glasses an acceptable simulation of the UV-B part of natural global radiation can be achieved. The ageing of these and other filter materials under the extreme UV radiation in the lamphouse of a solar simulator is presently unavoidable. This instability can be dealt with only by a precise spectral monitoring and by replacing the filters accordingly. For this reason attempts would be useful to develop real ozone filters which can replace glass filters. In any case chamber experiments require a careful selection of the filter material used and must be accompanied by a continuous UV-B monitoring.

Direct transfer of graphene onto flexible substrates.

Science.gov (United States)

Martins, Luiz G P; Song, Yi; Zeng, Tingying; Dresselhaus, Mildred S; Kong, Jing; Araujo, Paulo T

2013-10-29

In this paper we explore the direct transfer via lamination of chemical vapor deposition graphene onto different flexible substrates. The transfer method investigated here is fast, simple, and does not require an intermediate transfer membrane, such as polymethylmethacrylate, which needs to be removed afterward. Various substrates of general interest in research and industry were studied in this work, including polytetrafluoroethylene filter membranes, PVC, cellulose nitrate/cellulose acetate filter membranes, polycarbonate, paraffin, polyethylene terephthalate, paper, and cloth. By comparing the properties of these substrates, two critical factors to ensure a successful transfer on bare substrates were identified: the substrate's hydrophobicity and good contact between the substrate and graphene. For substrates that do not satisfy those requirements, polymethylmethacrylate can be used as a surface modifier or glue to ensure successful transfer. Our results can be applied to facilitate current processes and open up directions for applications of chemical vapor deposition graphene on flexible substrates. A broad range of applications can be envisioned, including fabrication of graphene devices for opto/organic electronics, graphene membranes for gas/liquid separation, and ubiquitous electronics with graphene.

Influence of substrate bias on the structure and properties of (Ti, Al)N films deposited by filtered cathodic vacuum arc

International Nuclear Information System (INIS)

Cheng, Y.H.; Tay, B.K.; Lau, S.P.; Shi, X.

2001-01-01

(Ti, Al)N films were deposited by an off-plane, double-bend, filtered cathodic vacuum arc technique in N 2 atmosphere at room temperature. The (Ti, Al)N films deposited are atomically smooth. The influence of substrate negative bias at the wide range (0-1000 V) on the deposition rate, surface morphology, crystal structure, internal stress, and mechanical properties of (Ti, Al)N films were systematically studied. Increasing substrate bias results in the decrease of deposition rate and the increase of surface roughness monotonically. At the bias of 0 V, (Ti, Al)N films are amorphous, and the internal stress, hardness, and Young's modulus for the deposited films are fairly low. With increasing substrate bias to 200 V, single-phase face-centered cubic-type nanocrystalline (Ti, Al)N films can be obtained, and the internal stress, hardness, and Young's modulus increase to the maximum of 7 GPa, 28 GPa, and 240 GPa, respectively. Further increase of substrate bias results in the decrease of intensity and the broadening of x-ray diffraction lines, and the gradual decrease of internal stress, hardness, and Young's modulus in (Ti, Al)N films

Poisson filtering of laser ranging data

Science.gov (United States)

Ricklefs, Randall L.; Shelus, Peter J.

1993-01-01

The filtering of data in a high noise, low signal strength environment is a situation encountered routinely in lunar laser ranging (LLR) and, to a lesser extent, in artificial satellite laser ranging (SLR). The use of Poisson statistics as one of the tools for filtering LLR data is described first in a historical context. The more recent application of this statistical technique to noisy SLR data is also described.

Direct transfer of graphene onto flexible substrates

Science.gov (United States)

Martins, Luiz G. P.; Song, Yi; Zeng, Tingying; Dresselhaus, Mildred S.; Kong, Jing; Araujo, Paulo T.

2013-01-01

In this paper we explore the direct transfer via lamination of chemical vapor deposition graphene onto different flexible substrates. The transfer method investigated here is fast, simple, and does not require an intermediate transfer membrane, such as polymethylmethacrylate, which needs to be removed afterward. Various substrates of general interest in research and industry were studied in this work, including polytetrafluoroethylene filter membranes, PVC, cellulose nitrate/cellulose acetate filter membranes, polycarbonate, paraffin, polyethylene terephthalate, paper, and cloth. By comparing the properties of these substrates, two critical factors to ensure a successful transfer on bare substrates were identified: the substrate’s hydrophobicity and good contact between the substrate and graphene. For substrates that do not satisfy those requirements, polymethylmethacrylate can be used as a surface modifier or glue to ensure successful transfer. Our results can be applied to facilitate current processes and open up directions for applications of chemical vapor deposition graphene on flexible substrates. A broad range of applications can be envisioned, including fabrication of graphene devices for opto/organic electronics, graphene membranes for gas/liquid separation, and ubiquitous electronics with graphene. PMID:24127582

Sub-micron filter

Science.gov (United States)

Tepper, Frederick [Sanford, FL; Kaledin, Leonid [Port Orange, FL

2009-10-13

Aluminum hydroxide fibers approximately 2 nanometers in diameter and with surface areas ranging from 200 to 650 m.sup.2/g have been found to be highly electropositive. When dispersed in water they are able to attach to and retain electronegative particles. When combined into a composite filter with other fibers or particles they can filter bacteria and nano size particulates such as viruses and colloidal particles at high flux through the filter. Such filters can be used for purification and sterilization of water, biological, medical and pharmaceutical fluids, and as a collector/concentrator for detection and assay of microbes and viruses. The alumina fibers are also capable of filtering sub-micron inorganic and metallic particles to produce ultra pure water. The fibers are suitable as a substrate for growth of cells. Macromolecules such as proteins may be separated from each other based on their electronegative charges.

Development of Filtered Bispectrum for EEG Signal Feature Extraction in Automatic Emotion Recognition Using Artificial Neural Networks

Directory of Open Access Journals (Sweden)

Prima Dewi Purnamasari

2017-05-01

Full Text Available The development of automatic emotion detection systems has recently gained significant attention due to the growing possibility of their implementation in several applications, including affective computing and various fields within biomedical engineering. Use of the electroencephalograph (EEG signal is preferred over facial expression, as people cannot control the EEG signal generated by their brain; the EEG ensures a stronger reliability in the psychological signal. However, because of its uniqueness between individuals and its vulnerability to noise, use of EEG signals can be rather complicated. In this paper, we propose a methodology to conduct EEG-based emotion recognition by using a filtered bispectrum as the feature extraction subsystem and an artificial neural network (ANN as the classifier. The bispectrum is theoretically superior to the power spectrum because it can identify phase coupling between the nonlinear process components of the EEG signal. In the feature extraction process, to extract the information contained in the bispectrum matrices, a 3D pyramid filter is used for sampling and quantifying the bispectrum value. Experiment results show that the mean percentage of the bispectrum value from 5 × 5 non-overlapped 3D pyramid filters produces the highest recognition rate. We found that reducing the number of EEG channels down to only eight in the frontal area of the brain does not significantly affect the recognition rate, and the number of data samples used in the training process is then increased to improve the recognition rate of the system. We have also utilized a probabilistic neural network (PNN as another classifier and compared its recognition rate with that of the back-propagation neural network (BPNN, and the results show that the PNN produces a comparable recognition rate and lower computational costs. Our research shows that the extracted bispectrum values of an EEG signal using 3D filtering as a feature extraction

Shielded regeneration heating element for a particulate filter

Science.gov (United States)

Gonze, Eugene V [Pinckney, MI; Ament, Frank [Troy, MI

2011-01-04

An exhaust system includes a particulate filter (PF) that is disposed downstream from an engine. The PF filters particulates within an exhaust from the engine. A heating element heats particulate matter in the PF. A catalyst substrate or a flow converter is disposed upstream from said heating element. The catalyst substrate oxidizes the exhaust prior to reception by the heating element. The flow converter converts turbulent exhaust flow to laminar exhaust flow prior to reception by the heating element.

AN APPLE GRADING SYSTEM ACCORDING TO EUROPEAN FRUIT QUALITY STANDARDS USING GABOR FILTER AND ARTIFICIAL NEURAL NETWORKS

Directory of Open Access Journals (Sweden)

KEYVAN ASEFPOUR VAKILIAN

2016-04-01

Full Text Available With the advent of applications of machine learning methods in food engineering in recent decades, several intelligent methods have been introduced in fruit grading technology. In this study, an apple grading system is presented using image’s textural features extraction and artificial intelligence. The objective of this study was to simplify the use of Gabor filter in classification of two varieties of apple fruits (Golden Delicious and Red Delicious in four categories according to the European fruit quality standards. Using this filter, neural network classifier was trained for four category grading of the fruits. Two textural parameters were extracted from each obtained image: mean and variance of energy values of obtained image representing image’s luminous intensity and contrast, respectively. Experimental results indicated that the training of extracted features of about 350 fruits enabled the network to classify the test samples with appropriate accuracy. Compared to the state-of-the-art, the proposed grading categories (‘Extra’, ‘Type 1’, ‘Type 2’ and ‘Rejected’ classes achieved acceptable recognition rates of about 89 % and 92 % overall accuracy for Golden Delicious and Red Delicious varieties, respectively. These experimental results show the appropriate application of proposed method in fast grading of apple fruits. Furthermore, proposed feature extraction and network training methods can be used efficiently in online applications.

Performance and optimisation of trickling filters on eel farms

NARCIS (Netherlands)

Kamstra, A.; Heul, van der J.W.; Nijhof, M.

1998-01-01

The design of trickling filters used on commercial eel farms differs considerably with respect to dimensions, hydraulic and substrate loads and filter medium applied. In this paper, a model, developed for ammonium removal in a pilot-scale trickling filter, has been validated for a range of

High temperature superconducting YBCO microwave filters

Science.gov (United States)

Aghabagheri, S.; Rasti, M.; Mohammadizadeh, M. R.; Kameli, P.; Salamati, H.; Mohammadpour-Aghdam, K.; Faraji-Dana, R.

2018-06-01

Epitaxial thin films of YBCO high temperature superconductor are widely used in telecommunication technology such as microwave filter, antenna, coupler and etc., due to their lower surface resistance and lower microwave loss than their normal conductor counterparts. Thin films of YBCO were fabricated by PLD technique on LAO substrate. Transition temperature and width were 88 K and 3 K, respectively. A filter pattern was designed and implemented by wet photolithography method on the films. Characterization of the filter at 77 K has been compared with the simulation results and the results for a made gold filter. Both YBCO and gold filters show high microwave loss. For YBCO filter, the reason may be due to the improper contacts on the feedlines and for gold filter, low thickness of the gold film has caused the loss increased.

Fully integrated low-loss band-pass filters for wireless applications

International Nuclear Information System (INIS)

Rais-Zadeh, M; Kapoor, A; Lavasani, H M; Ayazi, F

2009-01-01

Fully integrated low insertion loss micromachined band-pass filters are designed and fabricated on the silicon substrate (ρ = 10–20 Ω cm, ε r = 11.9) for UHF applications. Filters are made of silver, which has the highest conductivity of all metals, to minimize the ohmic loss. A detailed analysis for realizing low insertion loss and high out-of-band rejection filters using elliptic magnitude characteristics is presented, and a comprehensive model to take into account inductive parasitics of the interconnects is developed. Temperature characteristics of the filters are measured and show stable performance. The presented filters are different from the previously reported lumped element filters in that all filters are fully integrated on silicon substrate and occupy a remarkably smaller die area. Two filters are fabricated using the silver micromachining technique with center frequencies at 1.05 and 1.35 GHz. The filters have a constant 3 dB bandwidth of 300 MHz (28.6% and 22.2%) and an insertion loss of 1.4–1.7 dB. The low insertion loss and CMOS compatibility make the presented filters suitable candidates for radio frequency integrated circuits

MEMS flexible artificial basilar membrane fabricated from piezoelectric aluminum nitride on an SU-8 substrate

International Nuclear Information System (INIS)

Jang, Jongmoon; Choi, Hongsoo; Jang, Jeong Hun

2017-01-01

In this paper, we present a flexible artificial basilar membrane (FABM) that mimics the passive mechanical frequency selectivity of the basilar membrane. The FABM is composed of a cantilever array made of piezoelectric aluminum nitride (AlN) on an SU-8 substrate. We analyzed the orientations of the AlN crystals using scanning electron microscopy and x-ray diffraction. The AIN crystals are oriented in the c -axis (0 0 2) plane and effective piezoelectric coefficient was measured as 3.52 pm V −1 . To characterize the frequency selectivity of the FABM, mechanical displacements were measured using a scanning laser Doppler vibrometer. When electrical and acoustic stimuli were applied, the measured resonance frequencies were in the ranges of 663.0–2369 Hz and 659.4–2375 Hz, respectively. These results demonstrate that the mechanical frequency selectivity of this piezoelectric FABM is close to the human communication frequency range (300–3000 Hz), which is a vital feature of potential auditory prostheses. (paper)

High quality silicon-based substrates for microwave and millimeter wave passive circuits

Science.gov (United States)

Belaroussi, Y.; Rack, M.; Saadi, A. A.; Scheen, G.; Belaroussi, M. T.; Trabelsi, M.; Raskin, J.-P.

2017-09-01

Porous silicon substrate is very promising for next generation wireless communication requiring the avoidance of high-frequency losses originating from the bulk silicon. In this work, new variants of porous silicon (PSi) substrates have been introduced. Through an experimental RF performance, the proposed PSi substrates have been compared with different silicon-based substrates, namely, standard silicon (Std), trap-rich (TR) and high resistivity (HR). All of the mentioned substrates have been fabricated where identical samples of CPW lines have been integrated on. The new PSi substrates have shown successful reduction in the substrate's effective relative permittivity to values as low as 3.7 and great increase in the substrate's effective resistivity to values higher than 7 kΩ cm. As a concept proof, a mm-wave bandpass filter (MBPF) centred at 27 GHz has been integrated on the investigated substrates. Compared with the conventional MBPF implemented on standard silicon-based substrates, the measured S-parameters of the PSi-based MBPF have shown high filtering performance, such as a reduction in insertion loss and an enhancement of the filter selectivity, with the joy of having the same filter performance by varying the temperature. Therefore, the efficiency of the proposed PSi substrates has been well highlighted. From 1994 to 1995, she was assistant of physics at (USTHB), Algiers . From 1998 to 2011, she was a Researcher at characterization laboratory in ionized media and laser division at the Advanced Technologies Development Center. She has integrated the Analog Radio Frequency Integrated Circuits team as Researcher since 2011 until now in Microelectronic and Nanotechnology Division at Advanced Technologies Development Center (CDTA), Algiers. She has been working towards her Ph.D. degree jointly at CDTA and Ecole Nationale Polytechnique, Algiers, since 2012. Her research interest includes fabrication and characterization of microwave passive devices on porous

Alarm filtering and presentation

International Nuclear Information System (INIS)

Bray, M.A.

1989-01-01

This paper discusses alarm filtering and presentation in the control room of nuclear and other process control plants. Alarm generation and presentation is widely recognized as a general process control problem. Alarm systems often fail to provide meaningful alarms to operators. Alarm generation and presentation is an area in which computer aiding is feasible and provides clear benefits. Therefore, researchers have developed several computerized alarm filtering and presentation approaches. This paper discusses problems associated with alarm generation and presentation. Approaches to improving the alarm situation and installation issues of alarm system improvements are discussed. The impact of artificial intelligence (AI) technology on alarm system improvements is assessed. (orig.)

Complex laterally ordered InGaAs and InAs quantum dots by guided self-organized anisotropic strain engineering on artificially patterned GaAs (3 1 1)B substrates

NARCIS (Netherlands)

Selçuk, E.; Hamhuis, G.J.; Nötzel, R.

2009-01-01

Self-organized anisotropic strain engineering is combined with growth on artificially patterned GaAs (3 1 1)B substrates to realize complex lateral ordering of InGaAs and InAs quantum dots (QDs) guided by steps and facets generated along the pattern sidewalls. Depending on the pattern design, size,

Modeling enzymatic hydrolysis of lignocellulosic substrates using confocal fluorescence microscopy I: filter paper cellulose.

Science.gov (United States)

Luterbacher, Jeremy S; Moran-Mirabal, Jose M; Burkholder, Eric W; Walker, Larry P

2015-01-01

Enzymatic hydrolysis is one of the critical steps in depolymerizing lignocellulosic biomass into fermentable sugars for further upgrading into fuels and/or chemicals. However, many studies still rely on empirical trends to optimize enzymatic reactions. An improved understanding of enzymatic hydrolysis could allow research efforts to follow a rational design guided by an appropriate theoretical framework. In this study, we present a method to image cellulosic substrates with complex three-dimensional structure, such as filter paper, undergoing hydrolysis under conditions relevant to industrial saccharification processes (i.e., temperature of 50°C, using commercial cellulolytic cocktails). Fluorescence intensities resulting from confocal images were used to estimate parameters for a diffusion and reaction model. Furthermore, the observation of a relatively constant bound enzyme fluorescence signal throughout hydrolysis supported our modeling assumption regarding the structure of biomass during hydrolysis. The observed behavior suggests that pore evolution can be modeled as widening of infinitely long slits. The resulting model accurately predicts the concentrations of soluble carbohydrates obtained from independent saccharification experiments conducted in bulk, demonstrating its relevance to biomass conversion work. © 2014 Wiley Periodicals, Inc.

An ankle-foot orthosis powered by artificial pneumatic muscles.

Science.gov (United States)

Ferris, Daniel P; Czerniecki, Joseph M; Hannaford, Blake

2005-05-01

We developed a pneumatically powered orthosis for the human ankle joint. The orthosis consisted of a carbon fiber shell, hinge joint, and two artificial pneumatic muscles. One artificial pneumatic muscle provided plantar flexion torque and the second one provided dorsiflexion torque. Computer software adjusted air pressure in each artificial muscle independently so that artificial muscle force was proportional to rectified low-pass-filtered electromyography (EMG) amplitude (i.e., proportional myoelectric control). Tibialis anterior EMG activated the artificial dorsiflexor and soleus EMG activated the artificial plantar flexor. We collected joint kinematic and artificial muscle force data as one healthy participant walked on a treadmill with the orthosis. Peak plantar flexor torque provided by the orthosis was 70 Nm, and peak dorsiflexor torque provided by the orthosis was 38 Nm. The orthosis could be useful for basic science studies on human locomotion or possibly for gait rehabilitation after neurological injury.

Development of membrane filters with nanostructured porous layer by coating of metal nanoparticles sintered onto a micro-filter

International Nuclear Information System (INIS)

Park, Seok Joo; Park, Young Ok; Lee, Dong Geun; Ryu, Jeong In

2008-01-01

The membrane filter adhered with nanostructured porous layer was made by heat treatment after deposition of nanoparticle-agglomerates sintered in aerosol phase onto a conventional micron-fibrous metal filter as a substrate filter. The Sintered-Nanoparticle-Agglomerates-coated NanoStructured porous layer Membrane Filter (SNA-NSMF), whose the filtration performance was improved compared with the conventional metal membrane filters, was developed by adhesion of nanoparticle-agglomerates of dendrite structure sintered onto the micron-fibrous metal filter. The size of nanoparticle-agglomerates of dendrite structure decreased with increasing the sintering temperature because nanoparticle-agglomerates shrank. When shrinking nanoparticle-agglomerates were deposited and treated with heat onto the conventional micron-fibrous metal filter, pore size of nanostructured porous layer decreased. Therefore, pressure drops of SNA-NSMFs increased from 0.3 to 0.516 KPa and filtration efficiencies remarkably increased from 95.612 to 99.9993%

Exposure to space radiation of high-performance infrared multilayer filters

Science.gov (United States)

Seeley, J. S.; Hawkins, G. J.; Hunneman, R.

1991-01-01

The University of Reading experiment exposed IR interference filters and crystal substrates on identical earth facing and leading-edge sites of the Long Duration Exposure Facility (LDEF). Filters mostly comprised multilayer coatings of lead telluride (PbTe)/II-IV on germanium (Ge) and other substrates: crystals comprised CdTe, MgF2, sapphire, quartz, silicon, and some softer materials. Identical control samples were maintained in the laboratory throughout the experiment. The filters were novel in their design, construction and manufacture, and categorized high-performance because of their ability to resolve emission spectra of the important atmospheric gases for various purposes in remote sensing. No significant changes were found in the spectra of the hard-coated filters or in the harder crystals (the softer materials were degraded to an extent). By virtue of this well-documented and long exposure in LDEF, the qualification of the filter type is significantly improved for its future requirements.

Adhesion of rhodium films on metallic substrates

International Nuclear Information System (INIS)

Marot, L.; Covarel, G.; Tuilier, M.-H.; Steiner, R.; Oelhafen, P.

2008-01-01

Rhodium coated metallic films were prepared by magnetron sputtering on metallic substrates. All films were elaborated in same conditions on copper, molybdenum and stainless steel. Adhesion strength tests were carried out by scratch test. The results reveal that the adhesion strength between the film and the substrate is influenced by the hardness of the substrate. Increase of deposition temperature improves the adhesion of the coating. In addition, pre-treatment of substrates by a filtered cathodic vacuum arc and the layer thickness have has some effects on the final adhesion strength

Adhesion of rhodium films on metallic substrates

Energy Technology Data Exchange (ETDEWEB)

Marot, L. [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland)], E-mail: laurent.marot@unibas.ch; Covarel, G.; Tuilier, M.-H. [Laboratoire Mecanique, Materiaux et Procedes de Fabrication, Pole STIC-SPI-Math 61 rue Albert Camus, Universite de Haute-Alsace, F-68093 - Mulhouse Cedex (France); Steiner, R.; Oelhafen, P. [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland)

2008-09-01

Rhodium coated metallic films were prepared by magnetron sputtering on metallic substrates. All films were elaborated in same conditions on copper, molybdenum and stainless steel. Adhesion strength tests were carried out by scratch test. The results reveal that the adhesion strength between the film and the substrate is influenced by the hardness of the substrate. Increase of deposition temperature improves the adhesion of the coating. In addition, pre-treatment of substrates by a filtered cathodic vacuum arc and the layer thickness have has some effects on the final adhesion strength.

Neutron Imaging of Diesel Particulate Filters

International Nuclear Information System (INIS)

Strzelec, Andrea; Bilheux, Hassina Z.; Finney, Charles E.A.; Daw, C. Stuart; Foster, Dave; Rutland, Christopher J.; Schillinger, Burkhard; Schulz, Michael

2009-01-01

This article presents nondestructive neutron computed tomography (nCT) measurements of Diesel Particulate Filters (DPFs) as a method to measure ash and soot loading in the filters. Uncatalyzed and unwashcoated 200cpsi cordierite DPFs exposed to 100% biodiesel (B100) exhaust and conventional ultra low sulfur 2007 certification diesel (ULSD) exhaust at one speed-load point (1500rpm, 2.6bar BMEP) are compared to a brand new (never exposed) filter. Precise structural information about the substrate as well as an attempt to quantify soot and ash loading in the channel of the DPF illustrates the potential strength of the neutron imaging technique

Noise Reduction of Measurement Data using Linear Digital Filters

Directory of Open Access Journals (Sweden)

Hitzmann B.

2007-12-01

Full Text Available In this paper Butterworth, Chebyshev (Type I and II and Elliptic digital filters are designed for signal noise reduction. On-line data measurements of substrate concentration from E. coli fed-batch cultivation process are used. Application of the designed filters leads to a successful noise reduction of on-line glucose measurements. The digital filters presented here are simple, easy to implement and effective - the used filters allow for a smart compromise between signal information and noise corruption.

Quality of the Fosso della Casaccia: analysis of the macroinvertebrates colonizing artificial substrates; Stato di qualita` del fosso della Casaccia: analisi dei macroinvertebrati che colonizzano substrati artificiali

Energy Technology Data Exchange (ETDEWEB)

Prato, S.; Morgana, J.G.; Antonelli, D.; Folletto, A. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente

1999-01-01

Aim of this work is to analyse the environmental quality of a small stream, the Fosso della Casaccia, flowing near Research Centre of ENEA (Rome, Central Italy). The study was carried out comparing zoo benthic communities of two sampling sites, chosen upstream and downstream the sewage of the Research Centre. Macro invertebrates were sampled using artificial substrates and standard hand net. Taxa number and distribution along along the watercourse were compared. Moreover, biotic index values (I.B.E.=Indice Biotico Esteso) were calculated using data on macro invertebrates collected with both sampling methodologies. Artificial substrates were also useful in establishing colonization patterns at each sampling site, and bio masses of individuals belonging to different trophic groups. The results show the greater sampling effectiveness of artificial substrates, confirming their usefulness for establishing the environmental quality. [Italiano] Il presente lavoro prende in considerazione la qualita` ambientale del Fosso della Casaccia, un piccolo corso d`acqua che scorre in prossimita` del Centro di Ricerche ENEA Casaccia (Italia Centrale). Lo studio e` stato realizzato in base al confronto fra le comunita` zoobentoniche di due stazioni sperimentali situate a monte e a valle dello scarico di acque reflue del centro. Il campionamento dei macroinvertebrati e` stato effettuato utilizzando due diversi metodi di raccolta: i substrati artificiali e il retino immanicato standard. Gli organismi sono stati classificati in unita` sistematiche, e si e` analizzata la loro distribuzione lungo il corso d`acqua. Inoltre sono stati calcolati i valori degli indici biotici I.B.E. (Indice Biotico Esteso) utilizzando i dati ottenuti con le due metodologie di campionamento. L`uso di substrati artificiali in ogni stazione di campionamento e` stato utile anche per stabilire il tipo di colonizzazione, l`abbondanza e le biomasse degli individui appartenenti ai vari gruppi trofici. I nostri

Determination of the aerosol filters efficiency by means of the tracer techniques

International Nuclear Information System (INIS)

Hirling, J.

1978-01-01

Estimation of the nonradioactive methods of filters efficiency determination and tracer techniques are given. The methods are stated and discriptions of the instrumentation for estimation of the filters efficiency are given, in particular: methodology of production of the radioactive synthetic test-aerosols by means of the disperse and steamcondensation aerosol generators; the radio isotope method of the aerosol filters investigations; the methodology of filtartion efficiency determination. The results are given of the radioisotope investigations of filters; properties of the artificial radioactive test-aerosols; characteristics of filters, determined by the tracer techniques. Curves are given for the filtration efficiency of the viscose filtering nozzles of different density depending on the filters load. (I.T.) [ru

Far infrared filters for the Galileo-Jupiter and other missions

Science.gov (United States)

Seeley, J. S.; Hunneman, R.; Whatley, A.

1981-01-01

Progress in the development of FIR multilayer interference filters for the net flux radiometer and photopolarizing radiometer to be carried on board the Galileo mission to Jupiter is reported. The multilayer interference technique has been extended to the region above 40 microns by the use of PbTe/II-VI materials in hard-coated combination, with the thickest layers composed of CdSe QWOT at 74 microns and PbTe QWOT. Improvements have also been obtained in filters below 20 microns on the basis of the Chebyshev stack design. A composite filter cutting on steeply at 40 microns has been designed which employs a thin crystal quartz substrate, shorter wavelength absorption in ZnS and As2S3 thin films, and supplementary multilayer interference. Finally, absorptive filters have been developed based on II-VI compounds in multilayer combination with KRS-5 (or 6) on a KRS-5 (or 6) substrate

Responses of low pressure Andersen sampler for collecting substrates

Energy Technology Data Exchange (ETDEWEB)

Yamasaki, K. [Research Reactor Institute, Kyoto University, Osaka (Japan); Yamada, Y.; Miyamoto, K.; Shimo, M. [Division of Radiotoxicology and Protection, National Institute of Radiological Sciences, Chiba (Japan)

2000-05-01

Some types of low pressure cascade impactors (Andersen, Berner, Davies, and MOUDI etc) have been used to measure the activity size distribution of radon progeny in the environment. In spite of their careful uses, their nonideal responses are not adequately known. Some important factors such as the wall loss, electrostatic attraction, and the surface nature of collecting substrates may affect the reliability of the impactor data. Size selective characteristics of a low pressure Andersen sampler for various collecting substrates were examined in a radon exposure chamber using several kinds of liquid (DOS) or solid (carnauba wax) carrier aerosols labelled with radon progeny. These carrier aerosols were produced by commercial condensation aerosol generator. Tested collecting substrates were, (1) uncoated clean stainless steel plate, (2) silicone oil or grease coated stainless steel plate, (3) polyethylene sheet covered stainless steel plate, (4) membrane filter, (5) glass fiber filter, and (6) quartz fiber filter. In the case of collecting liquid or sticky carrier aerosols, the effect of particle bounce was small and nearly any substrates might used on the impaction plate. On the other hand, in the case of solid carrier aerosols, an adhesive layer such as grease or oil might have to be applied to the substrate. It was concluded that a low pressure cascade impactor such as Andersen sampler might need an appropriate calibration procedure including the interstage characteristics for determining the accurate activity size distribution. (author)

Cuttlefish dynamic camouflage: responses to substrate choice and integration of multiple visual cues.

Science.gov (United States)

Allen, Justine J; Mäthger, Lydia M; Barbosa, Alexandra; Buresch, Kendra C; Sogin, Emilia; Schwartz, Jillian; Chubb, Charles; Hanlon, Roger T

2010-04-07

Prey camouflage is an evolutionary response to predation pressure. Cephalopods have extensive camouflage capabilities and studying them can offer insight into effective camouflage design. Here, we examine whether cuttlefish, Sepia officinalis, show substrate or camouflage pattern preferences. In the first two experiments, cuttlefish were presented with a choice between different artificial substrates or between different natural substrates. First, the ability of cuttlefish to show substrate preference on artificial and natural substrates was established. Next, cuttlefish were offered substrates known to evoke three main camouflage body pattern types these animals show: Uniform or Mottle (function by background matching); or Disruptive. In a third experiment, cuttlefish were presented with conflicting visual cues on their left and right sides to assess their camouflage response. Given a choice between substrates they might encounter in nature, we found no strong substrate preference except when cuttlefish could bury themselves. Additionally, cuttlefish responded to conflicting visual cues with mixed body patterns in both the substrate preference and split substrate experiments. These results suggest that differences in energy costs for different camouflage body patterns may be minor and that pattern mixing and symmetry may play important roles in camouflage.

Artificial Material Integrated Ultra-wideband Tapered Slot Antenna for Gain Enhancement with Band Notch Characteristics

Directory of Open Access Journals (Sweden)

R. Singha

2018-04-01

Full Text Available The gain of the ultra-wideband tapered slot antenna (TSA is enhanced by using broadband artificial material with band notch characteristics. The proposed artificial material unit cell is designed by fabricating non-resonant three S-shaped parallel metallic line on single side of the dielectric substrate which provides a longer current path compared to the parallel-line structure. The proposed S-shaped structure is printed on the top side of the tapered slot antenna in the extended substrate periodically. The effective refractive index of the artificial material is lower than antenna substrate and phase velocity in the region of artificial material is much higher than the other region. Therefore, the proposed artificial material acts like a beam focusing lens. The band notch at 5.5 GHz is achieved by creating a split ring resonator (SRR slot near the balun. The basic and artificial material loaded TSAs are fabricated and the measurement results show that the gain of the basic antenna has been increased by 1.6 dBi. At the same time, the proposed antenna achieves a VSWR below 2 from 3 to 11 GHz except at 5.5 GHz with a notch band from 5.1 to 5.8 GHz for band rejection of wireless local area network (WLAN application.

Low pressure chemical vapour deposition of temperature resistant colour filters

International Nuclear Information System (INIS)

Verheijen, J.; Bongaerts, P.; Verspui, G.

1987-01-01

The possibility to deposit multilayer colour filters, based on optical inference, by means of Low Pressure Chemical Vapour Deposition (LPCVD) was investigated. The filters were made in a standard LPCVD system by alternate deposition of Si/sub 3/N/sub 4/ and SiO/sub 2/ layers. This resulted in filters with excellent colour uniformity on glass and quartz substrates. No difference was measured between theoretically calculated transmission and the transmission of the filters deposited by LPCVD. Temperature treatment at 600 0 C in air air showed no deterioration of filter quality and optical properties

Ciliated protozoa of two antarctic lakes: analysis by quantitative protargol staining and examination of artificial substrates

Science.gov (United States)

Kepner, R. L. Jr; Wharton, R. A. Jr; Coats, D. W.; Wharton RA, J. r. (Principal Investigator)

1999-01-01

Planktonic and artificial substrate-associated ciliates have been identified in two perennially ice-covered antarctic lakes of the McMurdo Dry Valleys. Abundances estimated by quantitative protargol staining ranged from < 5 to 31690 cells l-1, levels that are comparable to those previously obtained using other methods. Nineteen ciliate taxa were identified from these lakes, with the most frequently encountered genera being Plagiocampa, Askenasia, Monodinium, Sphaerophrya and Vorticella. The taxonomic findings compare favorably with those of previous investigators; however four previously unreported genera were observed in both Lakes Fryxell and Hoare. The variability in the depth distributions of ciliates in Lake Fryxell is explained in terms of lake physicochemical properties and ciliate prey distributions, while factors related to temporal succession in the Lake Hoare assemblage remain unexplained. Local marine or temperate zone freshwater habitats are a more likely source than the surrounding dry valleys soils for present ciliate colonists in these lakes. Although the taxonomic uncertainties require further examination, our results suggest that ciliate populations in these antarctic lakes undergo significant fluctuations and are more diverse than was previously recognized.

Artificial heart for humanoid robot

Science.gov (United States)

Potnuru, Akshay; Wu, Lianjun; Tadesse, Yonas

2014-03-01

A soft robotic device inspired by the pumping action of a biological heart is presented in this study. Developing artificial heart to a humanoid robot enables us to make a better biomedical device for ultimate use in humans. As technology continues to become more advanced, the methods in which we implement high performance and biomimetic artificial organs is getting nearer each day. In this paper, we present the design and development of a soft artificial heart that can be used in a humanoid robot and simulate the functions of a human heart using shape memory alloy technology. The robotic heart is designed to pump a blood-like fluid to parts of the robot such as the face to simulate someone blushing or when someone is angry by the use of elastomeric substrates and certain features for the transport of fluids.

A signal-substrate match in the substrate-borne component of a multimodal courtship display

Directory of Open Access Journals (Sweden)

Damian O. ELIAS, Andrew C. MASON, Eileen A. HEBETS

2010-06-01

Full Text Available The environment can impose strong limitations on the efficacy of signal transmission. In particular, for vibratory communication, the signaling environment is often extremely heterogeneous at very small scales. Nevertheless, natural selection is expected to select for signals well-suited to effective transmission. Here, we test for substrate-dependent signal efficacy in the wolf spider Schizocosa stridulans Stratton 1991. We first explore the transmission characteristics of this important signaling modality by playing recorded substrate-borne signals through three different substrates (leaf litter, pine litter, and red clay and measuring the propagated signal. We found that the substrate-borne signal of S. stridulans attenuates the least on leaf litter, the substrate upon which the species is naturally found. Next, by assessing mating success with artificially muted and non-muted males across different signaling substrates (leaf litter, pine litter, and sand, we explored the relationship between substrate-borne signaling and substrate for mating success. We found that muted males were unsuccessful in obtaining copulations regardless of substrate, while mating success was dependent on the signaling substrate for non-muted males. For non-muted males, more males copulated on leaf litter than any other substrate. Taken together, these results confirm the importance of substrate-borne signaling in S. stridulans and suggest a match between signal properties and signal efficacy – leaf litter transmits the signal most effectively and males are most successful in obtaining copulations on leaf litter [Current Zoology 56 (3: 370–378, 2010].

Effect of high substrate bias and hydrogen and nitrogen incorporation on filtered cathodic vacuum arc deposited tetrahedral amorphous carbon films

International Nuclear Information System (INIS)

Panwar, O.S.; Khan, Mohd. Alim; Kumar, Mahesh; Shivaprasad, S.M.; Satyanarayana, B.S.; Dixit, P.N.; Bhattacharyya, R.; Khan, M.Y.

2008-01-01

The application of a sufficiently high negative substrate bias, during the growth of tetrahedral amorphous carbon (ta-C), is usually associated with low sp 3 bonding configuration and stressed films. However, in an effort to understand and utilize the higher pseudo thermo dynamical conditions during the film growth, at high negative substrate bias (- 300 V), reported here is a study on ta-C films grown under different hydrogen and nitrogen concentration. As grown ta-C films were studied under different negative substrate bias conditions. The variation of the sp 3 content and sp 3 /sp 2 ratio in the ta-C films exhibits a trend similar to those reported in literature, with a subtle variation in this report being the substrate bias voltage, which was observed to be around - 200 V, for obtaining the highest sp 3 (80%) bonding and sp 3 /sp 2 (3.95) ratio. The hydrogen and nitrogen incorporated ta-C films studied, at a bias of - 300 V, show an increase in sp 3 (87-91%) bonding and sp 3 /sp 2 (7-10) ratio in the range of studies reported. The inference is drawn on the basis of the set of data obtained from measurements carried out using X-ray photoelectron spectroscopy, X-ray induced Auger electron spectroscopy and Raman spectroscopy of as grown and hydrogen and nitrogen incorporated ta-C films deposited using an S bend filtered cathodic vacuum arc system. The study indicates the possibility of further tailoring ta-C film properties and also extending capabilities of the cathodic arc system for developing carbon based films for electronics and tribological applications

Effect of high substrate bias and hydrogen and nitrogen incorporation on filtered cathodic vacuum arc deposited tetrahedral amorphous carbon films

Energy Technology Data Exchange (ETDEWEB)

Panwar, O.S. [Plasma Processed Materials Group, National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi-110 012 (India)], E-mail: ospanwar@mail.nplindia.ernet.in; Khan, Mohd. Alim [Plasma Processed Materials Group, National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi-110 012 (India); Kumar, Mahesh; Shivaprasad, S.M. [Surface Physics and Nanostructures Group, National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi-110 012 (India); Satyanarayana, B.S. [MIT Innovation Centre and Electronics and Communication Department, Manipal Institute of Technology, Manipal-579104 (India); Dixit, P.N. [Plasma Processed Materials Group, National Physical Laboratory, Dr. K.S. Krishnan Road, New Delhi-110 012 (India); Bhattacharyya, R. [Emeritus Scientist, National Physical Laboratory, New Delhi-110012 (India); Khan, M.Y. [Department of Physics, Jamia Millia Islamia, Central University, New Delhi-110025 (India)

2008-02-29

The application of a sufficiently high negative substrate bias, during the growth of tetrahedral amorphous carbon (ta-C), is usually associated with low sp{sup 3} bonding configuration and stressed films. However, in an effort to understand and utilize the higher pseudo thermo dynamical conditions during the film growth, at high negative substrate bias (- 300 V), reported here is a study on ta-C films grown under different hydrogen and nitrogen concentration. As grown ta-C films were studied under different negative substrate bias conditions. The variation of the sp{sup 3} content and sp{sup 3}/sp{sup 2} ratio in the ta-C films exhibits a trend similar to those reported in literature, with a subtle variation in this report being the substrate bias voltage, which was observed to be around - 200 V, for obtaining the highest sp{sup 3} (80%) bonding and sp{sup 3}/sp{sup 2} (3.95) ratio. The hydrogen and nitrogen incorporated ta-C films studied, at a bias of - 300 V, show an increase in sp{sup 3} (87-91%) bonding and sp{sup 3}/sp{sup 2} (7-10) ratio in the range of studies reported. The inference is drawn on the basis of the set of data obtained from measurements carried out using X-ray photoelectron spectroscopy, X-ray induced Auger electron spectroscopy and Raman spectroscopy of as grown and hydrogen and nitrogen incorporated ta-C films deposited using an S bend filtered cathodic vacuum arc system. The study indicates the possibility of further tailoring ta-C film properties and also extending capabilities of the cathodic arc system for developing carbon based films for electronics and tribological applications.

formulation of nano-ceramic filters used in separation of heavy metals and nuclear technology

International Nuclear Information System (INIS)

Khalil, T.; Labib, Sh.; Abou El-Nour, F.H.; Abdel-Khalik, M.

2004-01-01

the choice of suitable preparation methods and experimental preparation conditions to formulate ceramic filters of stable chemical -and thermal properties and of high mechanical strength and stable structure, which permit their use for separation of heavy metals at high separation conditions and to produce compact matrices suitable for radiation protection are the aim of this study . ceramic filters are characterized by multi- layered body including rigid support and one or more layers with pore size lower than that of the support. the top layer determines.the separation conditions of the whole system. the used ceramic filters include micro-, ultra- and nano-sized materials . alumina and titania substrates were prepared using the wet chemical techniques. optimization of the produced substrates was followed through comparative studies with standard reference commercial substrate. specific surface area measurements and pore size distribution using mercury porosimeter were carried out . the present study led to optimization of the experimental conditions to formulate the suitable substrate used in preparation of filters applied in separation of heavy metals. in addition, their use to produce compact matrices suitable for protection from the hazardous effect of some radioisotopes could applied

Planar Superconducting Millimeter-Wave/Terahertz Channelizing Filter

Science.gov (United States)

Ehsan, Negar; U-yen, Kongpop; Brown, Ari; Hsieh, Wen-Ting; Wollack, Edward; Moseley, Samuel

2013-01-01

This innovation is a compact, superconducting, channelizing bandpass filter on a single-crystal (0.45 m thick) silicon substrate, which operates from 300 to 600 GHz. This device consists of four channels with center frequencies of 310, 380, 460, and 550 GHz, with approximately 50-GHz bandwidth per channel. The filter concept is inspired by the mammalian cochlea, which is a channelizing filter that covers three decades of bandwidth and 3,000 channels in a very small physical space. By using a simplified physical cochlear model, and its electrical analog of a channelizing filter covering multiple octaves bandwidth, a large number of output channels with high inter-channel isolation and high-order upper stopband response can be designed. A channelizing filter is a critical component used in spectrometer instruments that measure the intensity of light at various frequencies. This embodiment was designed for MicroSpec in order to increase the resolution of the instrument (with four channels, the resolution will be increased by a factor of four). MicroSpec is a revolutionary wafer-scale spectrometer that is intended for the SPICA (Space Infrared Telescope for Cosmology and Astrophysics) Mission. In addition to being a vital component of MicroSpec, the channelizing filter itself is a low-resolution spectrometer when integrated with only an antenna at its input, and a detector at each channel s output. During the design process for this filter, the available characteristic impedances, possible lumped element ranges, and fabrication tolerances were identified for design on a very thin silicon substrate. Iterations between full-wave and lumped-element circuit simulations were performed. Each channel s circuit was designed based on the availability of characteristic impedances and lumped element ranges. This design was based on a tabular type bandpass filter with no spurious harmonic response. Extensive electromagnetic modeling for each channel was performed. Four channels

In vitro cultivation of pineapple seedlings using filters, artificial ventilation and sucrose = Cultivo in vitro de plântulas de abacaxizeiro com uso de filtros, ventilação artificial e sacarose

Directory of Open Access Journals (Sweden)

Patrícia dos Santos Mendes

2015-06-01

Full Text Available An alternative to the production of quality seedlings is the use of in-vitro systems of propagation. However, the conventional in-vitro environment is different from the external environment, and is often the reason for physiological and morphological disorders in the plant. To this effect, the aim of this study was to evaluate the use of filters and artificial ventilation to increase air exchange between the flask and environment, and adjust the concentration of sucrose in the culture medium for a better development of the photosynthetic apparatus, and stimulate the growth of pineapple plants in vitro. The experimental design was completely randomised in a 3 x 3 factorial scheme with nine replications. The factors under study consisted of three concentrations of sucrose (0, 15, and 30 g L-1 and three methods for ventilating the flask (unfiltered flask with no ventilation, filtered flask with no ventilation, and filtered flask with ventilation. The use of unfiltered flasks with no ventilation and 15 g L-1 of added sucrose, result in greater growth of the pineapple plants in vitro. The use of filtered flasks with ventilation promotes an increase in the levels of chlorophyll-a, chlorophyll-b, and total chlorophyll, as well as improvements in the system of photosynthesis of the pineapple seedlings = Uma alternativa para a produção de mudas de qualidade é a utilização de sistemas de propagação in vitro . Porém, o ambiente de cultivo convencional in vitro é diferente do ambiente externo e comumente há razão de distúrbios fisiológicos e morfológicos na planta. Neste contexto, objetivou-se com o presente trabalho avaliar o uso de filtros e ventilação artificial visando aumentar as trocas de ar do frasco com o ambiente e ajustar a concentração de sacarose no meio de cultura para o melhor desenvolvimento do aparelho fotossintético e estímulo do crescimento das plantas in vitro de abacaxizeiro. O delineamento experimental foi

Efeito de substratos, luz e sobreposição de papel de filtro na esporulação de Corynespora cassiicola Effect of substrates, light and filter paper on Corynespora cassiicola sporulation

Directory of Open Access Journals (Sweden)

Márcia Muliterno de Melo

2010-09-01

Full Text Available O experimento foi realizado no Laboratório de Fitopatologia - Micologia, na Faculdade de Agronomia e Medicina Veterinária da Universidade de Passo Fundo, com a finalidade de avaliar a esporulação de Corynespora cassiicola em diferentes substratos. Para isso foram usadas placas de petri com seis diferentes meio de cultura - Batata Dextrose Ágar (BDA, Solução Czapek Ágar, Alimento infantil, Malte Ágar, Farinha de aveia e suco V8 Ágar e quatro combinações (com luz alternada e sobreposição de papel filtro, com luz alternada e sem sobreposição de papel filtro, sem luz com sobreposição de papel filtro e sem luz e sem sobreposição de papel filtro. O delineamento experimental usado foi fatorial triplo (substrato, luz/escuro, com ou sem sobreposição de papel filtro. Na avaliação de esporulação do fungo, foram cortados dois discos de 0,241cm² em cada placa dos diferentes substratos e colocados em tubos de ensaio contendo 10mL de água destilada. Esses tubos foram agitados e de cada um foram retiradas três alíquotas de 10mL para contagem de conídios no microscópio óptico. Os dados foram transformados em número de esporos.cm². A maior esporulação do fungo foi obtida com o substrato Solução Czapek-Ágar, com fotoperíodo de 12 horas e sobreposição de papel filtro.This experiment was carried out in the Laboratory of Phytopathology - Mycology - School of Agronomy and Veterinary Medicine, Passo Fundo University, in order to evaluate Corynespora cassiicola sporulation on different substrates. Thus the used Petri plates contained six different culture media - Potato Dextrose Agar (PDA, Czapek Solution Agar, infant food, Malt Agar, Oatmeal Agar, and V8 juice agar, besides four combinations (with both light and filter paper, with light and without filter paper, with filter paper and without light, and without light and without filter paper. Experimental design was triple factorial (substrate, light / dark, with or without

Effects of substrate concentration, specific surface area and hydraulic loading on the treatment efficiency in a submerged biological filter. Sesshoku bakkiho no shori koritsu ni taisuru kishitsu nodo, hihyo menseki oyobi suiryo fuka no eikyo

Energy Technology Data Exchange (ETDEWEB)

Iyo, T; Ono, S; Yoshino, T [Kitasato University, Kanagawa (Japan). School of Hygienic Science

1991-06-10

Effects of substrate concentration, specific surface area, and hydraulic loading, which are major factors influencing treatment efficiency in a submerged biological filter, were analyzed through the test with a special apparatus. In the test, the wall of the submerged biological filter was regarded as the contact material, and the specific surface area was changed by adjusting the sectional form of the filter. Using specimens from actual plant reservoirs, treatment efficiency for each case of three kinds of substrate concentration and hydraulic loading was measured. BOD removal rate was lower with smaller specific surface area. It was conspicuous particularly with higher BOD concentration in influent water. After the multiple regression analysis of the test results, the multiple regression equation to estimate BOD residual rate from three variates such as BOD concentration, specific surface area, and hydraulic loading was obtained. When 200mg l as BOD concentration and 50m{sup 2} m{sup {minus}3} as specific surface area were applied in this equation, the result almost agreed with the tendency obtained from data of actual plants. 6 refs., 4 figs., 1 tab.

Compact microstrip bandpass filter with tunable notch

DEFF Research Database (Denmark)

Christensen, Silas; Zhurbenko, Vitaliy; Johansen, Tom Keinicke

2014-01-01

Two different designs combining a bandpass and a notch filter are developed to operate in the receiving band from 350–470 MHz. The bandpass filter is designed from a simple structure, by use of only four short circuited stubs and a half wavelength transmission line connecting the stubs. The tunable...... notch filter ensures an attenuation level of 19.3 dB to 27.3 dB in the frequency range from 360–480 MHz. The measured passband ripple of the combined filter is less than 0.5 dB, while the insertion loss for the simplest design is less than 1.7 dB only 10 MHz from the notch frequency. Even though...... the wavelength on the selected substrate (εr = 3.55) is approximately 45 cm, the outer dimensions of the final filter only measure 10×10 cm2....

Stresses and Temperature Stability of Dense Wavelength Division Multiplexing Filters Prepared by Reactive Ion-Assisted E-Gun Evaporation

Science.gov (United States)

Wei, Chao-Tsang; Shieh, Han-Ping D.

2005-10-01

In this paper, we report the in situ measurement of the temperature stability of narrow-band-pass filters on different types of substrate, for dense wavelength division multiplexing (DWDM) filters in optical-fiber transmission systems. The DWDM filters were designed as all-dielectric Fabry-Perot filters and fabricated by reactive ion-assisted deposition. Ta2O5 and SiO2 were used as high- and low-refractive-index layers, respectively, for constructing the DWDM filters. The accuracy and stability of the coating process were evaluated for fabricating the DWDM filters for the temperature stability of the center wavelength. The center wavelength shift was determined to be greatly dependent on the coefficient of thermal expansion of the substrate on which the filter is deposited.

Bacterial growth and substrate degradation by BTX-oxidizing culture in response to salt stress.

Science.gov (United States)

Lee, Chi-Yuan; Lin, Ching-Hsing

2006-01-01

Interactions between microbial growth and substrate degradation are important in determining the performance of trickle-bed bioreactors (TBB), especially when salt is added to reduce biomass formation in order to alleviate media clogging. This study was aimed at quantifying salinity effects on bacterial growth and substrate degradation, and at acquiring kinetic information in order to improve the design and operation of TBB. Experiment works began by cultivating a mixed culture in a chemostat reactor receiving artificial influent containing a mixture of benzene, toluene, and xylene (BTX), followed by using the enrichment culture to degrade the individual BTX substrates under a particular salinity, which ranged 0-50 g l(-1) in batch mode. Then, the measured concentrations of biomass and residual substrate versus time were analyzed with the microbial kinetics; moreover, the obtained microbial kinetic constants under various salinities were modeled using noncompetitive inhibition kinetics. For the three substrates the observed bacterial yields appeared to be decreased from 0.51-0.74 to 0.20-0.22 mg mg(-1) and the maximum specific rate of substrate utilization, q, declined from 0.25-0.42 to 0.07-0.11 h(-1), as the salinity increased from 0 to 50 NaCl g l(-1). The NaCl acted as noncompetitive inhibitor, where the modeling inhibitions of the coefficients, K ( T(S)), were 22.7-29.7 g l(-1) for substrate degradation and K ( T(mu)), 13.0-19.0 g l(-1), for biomass formation. The calculated ratios for the bacterial maintenance rate, m (S), to q, further indicated that the percentage energy spent on maintenance increased from 19-24 to 86-91% as salinity level increased from 0 to 50 g l(-1). These results revealed that the bacterial growth was more inhibited than substrate degradation by the BTX oxidizers under the tested salinity levels. The findings from this study demonstrate the potential of applying NaCl salt to control excessive biomass formation in biotrickling filters.

Wavelength selectivity of on-axis surface plasmon laser filters

International Nuclear Information System (INIS)

Harmer, S W; Townsend, P D

2002-01-01

Excitation of surface plasmons on a metal substrate, via the attenuated total reflection method can theoretically offer preferential absorption of light at one particular wavelength, whilst reflecting the nearby spectrum. Normally this 'filtering' action is limited to removal of p-polarized light, and the acceptance angle of such a filtering device is very narrow, which limits practical applications, such as separation of fundamental and laser harmonics. The possibility of avoiding this angular precision is explored by considering the complex permittivity of metal composites. By using a two or more layer structure, as opposed to a single metal substrate, the acceptance angle of the device can be broadened, by a factor of about 15 times. An example is discussed for separation of the fundamental and harmonics from a Nd : YAG laser. Variants of the structure allow the design of an in-line transmission filter for the various wavelengths with sufficient angular tolerance to include focusing lenses. Avoidance of laser ablation of the metal is discussed

Design of a micromachined terahertz electromagnetic crystals (EMXT) channel-drop filter on silicon-substrate

Science.gov (United States)

Zhou, Kai; Liu, Yong; Si, Liming; Lv, Xin

2013-08-01

An integrated 0.5 THz electromagnetic crystals(EMXT) channel-drop filter based on PBG structure is presented in this paper. A channel-drop filter is a device in which a narrow bandwidth is redirected to another "drop" waveguide while other frequencies are unaffected. It's capable of extracting a certain frequency from a continuous spectrum in the bus channel and passing it to the test channel. It has potential applications in photonic integrated circuits, radio astronomy, THz spectroscopy, THz communication and remote sensing radar receiver. PBG structures(or photonic crystals) are periodic structures which possess band gaps, where the electromagnetic wave of certain ranges of frequencies cannot pass through and is reflected. The proposed channel-drop filter consists of input waveguide,output waveguide and PBG structure. The proposed filter is simulated using the finite element method and can be fabricated by micro-electromechanical systems (MEMS) technology,due to its low cost, high performance and high processing precision.The filter operation principle and fabrication process are discussed.The simulation results show its ability to filter the frequency of 496GHz with a linewidth of approximately 4GHz and transmission of 27.2 dB above background.The loss at resonant frequency is less than 1dB considering the thickness and roughness of gold layer required by the MEMS process.The channel drop efficiency is 84%.

Estimation of three-dimensional radar tracking using modified extended kalman filter

Science.gov (United States)

Aditya, Prima; Apriliani, Erna; Khusnul Arif, Didik; Baihaqi, Komar

2018-03-01

Kalman filter is an estimation method by combining data and mathematical models then developed be extended Kalman filter to handle nonlinear systems. Three-dimensional radar tracking is one of example of nonlinear system. In this paper developed a modification method of extended Kalman filter from the direct decline of the three-dimensional radar tracking case. The development of this filter algorithm can solve the three-dimensional radar measurements in the case proposed in this case the target measured by radar with distance r, azimuth angle θ, and the elevation angle ϕ. Artificial covariance and mean adjusted directly on the three-dimensional radar system. Simulations result show that the proposed formulation is effective in the calculation of nonlinear measurement compared with extended Kalman filter with the value error at 0.77% until 1.15%.

Development of an alternative artificial soil for earthworm toxicity testing in tropical countries.

NARCIS (Netherlands)

de Silva, M.; van Gestel, C.A.M.

2009-01-01

The standard soil invertebrate toxicity tests developed by OECD and ISO use an artificial soil as the test substrate, which contains sphagnum peat as a component. This type of peat is not widely available. Investigation of possible alternative substrates using locally available materials therefore

Estimation of dynamic reactivity using an H∞ optimal filter with a nonlinear term

International Nuclear Information System (INIS)

Suzuki, Katsuo; Watanabe, Koiti

1996-01-01

A method of nonlinear filtering is applied to the problem of estimating the dynamic reactivity of a nonlinear reactor system. The nonlinear filtering algorithm developed is a simple modification of a linear H ∞ optimal filter with a nonlinear feedback loop added. The linear filter is designed on the basis of a linearized dynamical system model that consists of linearized point reactor kinetic equations and a reactivity state equation driven by a fictitious signal. The latter is artificially introduced to deal with the reactivity as a state variable. The results of the computer simulation show that the nonlinear filtering algorithm can be applied to estimate the dynamic reactivity of the nonlinear reactor system, even under relatively large reactivity disturbances

Impact of artificial rearing systems on the developmental and reproductive fitness of the predatory bug, Orius laevigatus.

Science.gov (United States)

Bonte, Maarten; De Clercq, Patrick

2010-01-01

This study investigated the effect of several substrate types and moisture sources on the developmental and reproductive fitness of the zoophytophagous predator Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) when fed a factitious prey (i.e. unnatural prey) Ephestia kuehniella (Zeller) eggs, or a meridic artificial diet based on hen's egg yolk. O. laevigatus is known to feed on plants as an alternative food source and to oviposit in plants. E. kuehniella eggs were superior to the artificial diet. Supplementary feeding on plant materials did not compensate for the nutritional shortcomings of the artificial diet. Survival rates showed that oviposition substrates such as bean pods or lipophilic surfaces such as wax paper and plastic were more suitable for rearing O. laevigatus than household paper. The use of green bean pods as a plant substrate did not have a beneficial effect on O. laevigatus. The results indicated that O. laevigatus can successfully complete its nymphal development and realize its full reproductive potential in the absence of plant material. However, plant materials would still be required for oviposition, unless a reliable and cost-effective artificial oviposition substrate were made available. The omission of plant materials from the rearing procedures may reduce production cost of this species and other heteropteran predators.

Confocal filtering in cathodoluminescence microscopy of nanostructures

Science.gov (United States)

Narváez, Angela C.; Weppelman, I. Gerward C.; Moerland, Robert J.; Hoogenboom, Jacob P.; Kruit, Pieter

2014-06-01

Cathodoluminescence (CL) microscopy allows optical characterization of nanostructures at high spatial resolution. At the nanoscale, a main challenge of the technique is related to the background CL generated within the sample substrate. Here, we implement confocal detection of the CL signal to minimize the background contribution to the measurement. Nano-phosphors were used as point sources to evaluate the filtering capabilities of our confocal CL system, obtaining an axial intensity profile with 2.7 μm full width at half maximum for the central peak, in good correspondence with theoretical expectations. Considering the electron interaction volume, we found that the confocal filter becomes effective for electron energies above 20 keV, when using a 25 μm pinhole (0.86 Airy units). To illustrate our approach, we present confocal CL imaging of gold nanowires and triangular shaped plates deposited on an indium-tin oxide covered glass substrate, comparing the images with those obtained in standard unfiltered CL detection. The results show that confocal CL microscopy is a valuable tool for the investigation of nanostructures on highly cathodoluminescent substrates, widely used in biological and optical applications.

Confocal filtering in cathodoluminescence microscopy of nanostructures

Energy Technology Data Exchange (ETDEWEB)

Narváez, Angela C., E-mail: a.c.narvaez@tudelft.nl, E-mail: j.p.hoogenboom@tudelft.nl; Weppelman, I. Gerward C.; Moerland, Robert J.; Hoogenboom, Jacob P., E-mail: a.c.narvaez@tudelft.nl, E-mail: j.p.hoogenboom@tudelft.nl; Kruit, Pieter [Imaging Physics, Faculty of Applied Sciences, Delft University of Technology, Lorentzweg 1, 2628CJ Delft (Netherlands)

2014-06-23

Cathodoluminescence (CL) microscopy allows optical characterization of nanostructures at high spatial resolution. At the nanoscale, a main challenge of the technique is related to the background CL generated within the sample substrate. Here, we implement confocal detection of the CL signal to minimize the background contribution to the measurement. Nano-phosphors were used as point sources to evaluate the filtering capabilities of our confocal CL system, obtaining an axial intensity profile with 2.7 μm full width at half maximum for the central peak, in good correspondence with theoretical expectations. Considering the electron interaction volume, we found that the confocal filter becomes effective for electron energies above 20 keV, when using a 25 μm pinhole (0.86 Airy units). To illustrate our approach, we present confocal CL imaging of gold nanowires and triangular shaped plates deposited on an indium-tin oxide covered glass substrate, comparing the images with those obtained in standard unfiltered CL detection. The results show that confocal CL microscopy is a valuable tool for the investigation of nanostructures on highly cathodoluminescent substrates, widely used in biological and optical applications.

Low-voltage protonic/electronic hybrid indium zinc oxide synaptic transistors on paper substrates

International Nuclear Information System (INIS)

Wu, Guodong; Wan, Changjin; Wan, Qing; Zhou, Jumei; Zhu, Liqiang

2014-01-01

Low-voltage (1.5 V) indium zinc oxide (IZO)-based electric-double-layer (EDL) thin-film transistors (TFTs) gated by nanogranular proton conducting SiO 2 electrolyte films are fabricated on paper substrates. Both enhancement-mode and depletion-mode operation are obtained by tuning the thickness of the IZO channel layer. Furthermore, such flexible IZO protonic/electronic hybrid EDL TFTs can be used as artificial synapses, and synaptic stimulation response and short-term synaptic plasticity function are demonstrated. The protonic/electronic hybrid EDL TFTs on paper substrates proposed here are promising for low-power flexible paper electronics, artificial synapses and bioelectronics. (paper)

Tunable bandpass filter based on partially magnetized ferrite LTCC with embedded windings for SoP applications

KAUST Repository

Arabi, Eyad A.

2015-01-01

Tunable filters that are based on ferrite materials often require large and bulky electromagnets. In this work, we present a tunable filter in the Ku-band, which is realized in multilayer ferrite LTCC substrate with embedded bias windings, thus negating the need of a large electromagnet. Also, because of the embedded windings, the bias fields are not lost at the air-substrate interface and therefore the field and current requirements are reduced by an order of magnitude as compared to the previously reported filters. A simulation strategy that uses full permeability tensor with arbitrarily directed magnetic fields has been used to model the filter on a partially magnetized ferrite substrate. Special attention has also been paid to approximate the non-uniform magneto-static fields produced by the embedded windings. The complete design is implemented in 10 layers of ferrite LTCC, making it the first magnetically tunable filter with embedded windings and extremely small size [(5 × 5 × 1.1)mm3]. The filter demonstrates a measured tunability of 4% and an insertion loss of 2.3 dB. With the small form factor, embedded windings, and low bias requirements, the design is highly suitable for compact and tunable SoP applications.

Raman imaging using fixed bandpass filter

Science.gov (United States)

Landström, L.; Kullander, F.; Lundén, H.; Wästerby, P.

2017-05-01

By using fixed narrow band pass optical filtering and scanning the laser excitation wavelength, hyperspectral Raman imaging could be achieved. Experimental, proof-of-principle results from the Chemical Warfare Agent (CWA) tabun (GA) as well as the common CWA simulant tributyl phosphate (TBP) on different surfaces/substrates are presented and discussed.

[Influence of nutritional substrates on the development of Diaphania hyalinata L. (Lepidoptera: Crambidae)].

Science.gov (United States)

Pratissoli, Dirceu; Polanczyk, Ricardo A; Holtz, Anderson M; Tamanhoni, Tiago; Celestino, Flávio N; Borges Filho, Raul da C

2008-01-01

The aim of this research was to evaluate the biological behaviour of melonworm at different natural and artificial diets. Squash cultivar jacaré, cucumber, summer squash and an artificial diets developed by Hensley & Hammond for the sugarcane borer were tried. The research was carried out in the Laboratório de Entomologia do Centro de Ciências Agrárias of the Universidade Federal do Espírito Santo, in climatized room at 25 +/- 1 masculineC, relative humidity of 70 +/- 10% and 14h photofase. The caterpillars fed on each substrate during the whole life cycle. Differences in duration of the larval period, larvae and pupae survival, adult longevity and number of eggs were registered between the substrates. The results show that the best diet for rearing is the artificial one. Between the natural diets the cucumber showed the best results.

Artificial high effective permittivity medium in a SIW filled with metallic cylinders

Science.gov (United States)

Vicent, G.; Bronchalo, E.; Coves, A.; Torregrosa, G.

2018-02-01

A new topology of step-impedance band-pass filters in Substrate Integrated Waveguide (SIW) technology has been recently demonstrated in which low effective permittivity regions have been achieved by removing part of the substrate material and then shielding the perforated structure. Alternatively, in this work a new way to obtain an increased relative permittivity in the guiding region is proposed by periodically inserting metallic inclusions. This paper shows the results of a systematic study of the effective permittivity obtained in this way in a SIW in order to synthesize a higher effective permittivity, which can be used in the filter design.

A Pathway to Artificial Metalloenzymes

KAUST Repository

Fischer, Johannes

2015-12-01

The advancement of catalytic systems and the application thereof has proven to be the key to overcome traditional limitations of industrial-scale synthetic processes. Converging organometallic and biocatalytic principles lead to the development of Artificial Metalloenzymes (ArMs) that comprise a synthetic metal catalyst embedded in a protein scaffold, thereby combining the reactivity of the former with the versatility of the latter. This synergistic approach introduces rationally designed building blocks for the catalytic site and the host protein to assemble enzyme-like structures that follow regio-, chemo-, enantio- and substrate-selective principles. Yet, the identification of suitable protein scaffolds has thus far been challenging. Herein we report a rationally optimized fluorescent protein host, mTFP*, that was engineered to have no intrinsic metal binding capability and, owing to its robust nature, can act as scaffold for the design of novel ArMs. We demonstrate the potential of site-specific modifications within the protein host, use protein X-Ray analysis to validate the respective scaffolds and show how artificial mutant binding sites can be introduced. Transition metal Förster Resonance Energy transfer (tmFRET) methodologies help to evaluate micromolar dissociation constants and reveal structural rearrangements upon coordination of the metal centers. In conjunction with molecular insights from X-Ray crystallographic structure determination, dynamics of the binding pocket can be inferred. The versatile subset of different binding motifs paired with transition metal catalysts create artificial metalloenzymes that provide reactivities which otherwise do not exist in nature. As a proof of concept, Diels-Alder cycloadditions highlight the potential of the present mTFP* based catalysts by stereoselectively converting azachalcone and cyclopentadiene substrates. Screens indicate an enantiomeric excess of up to 60% and provide insights into the electronic and

DC-pass filter design with notch filters superposition for CPW rectenna at low power level

Science.gov (United States)

Rivière, J.; Douyère, A.; Alicalapa, F.; Luk, J.-D. Lan Sun

2016-03-01

In this paper the challenging coplanar waveguide direct current (DC) pass filter is designed, analysed, fabricated and measured. As the ground plane and the conductive line are etched on the same plane, this technology allows the connection of series and shunt elements to the active devices without via holes through the substrate. Indeed, this study presents the first step in the optimization of a complete rectenna in coplanar waveguide (CPW) technology: key element of a radio frequency (RF) energy harvesting system. The measurement of the proposed filter shows good performance in the rejection of F0=2.45 GHz and F1=4.9 GHz. Additionally, a harmonic balance (HB) simulation of the complete rectenna is performed and shows a maximum RF-to-DC conversion efficiency of 37% with the studied DC-pass filter for an input power of 10 µW at 2.45 GHz.

The use of dried cerebrospinal fluid filter paper spots as a substrate for PCR diagnosis of the aetiology of bacterial meningitis in the Lao PDR

Science.gov (United States)

Elliott, I; Dittrich, S; Paris, D; Sengduanphachanh, A; Phoumin, P; Newton, P N

2013-01-01

We investigated whether dried cerebrospinal fluid (CSF) conserved on filter paper can be used as a substrate for accurate PCR diagnosis of important causes of bacterial meningitis in the Lao PDR. Using mock CSF, we investigated and optimized filter paper varieties, paper punch sizes, elution volumes and quantities of DNA template to achieve sensitive and reliable detection of bacterial DNA from filter paper specimens. FTA Elute Micro Card™ (Whatman, Maidstone, UK) was the most sensitive, consistent and practical variety of filter paper. Following optimization, the lower limit of detection for Streptococcus pneumoniae from dried mock CSF spots was 14 genomic equivalents (GE)/μL (interquartile range 5.5 GE/μL) or 230 (IQR 65) colony forming units/mL. A prospective clinical evaluation for S. pneumoniae, S. suis and Neisseria meningitidis was performed. Culture and PCR performed on fresh liquid CSF from patients admitted with a clinical diagnosis of meningitis (n = 73) were compared with results derived from dried CSF spots. Four of five fresh PCR-positive CSF samples also tested PCR positive from dried CSF spots, with one patient under the limit of detection. In a retrospective study of S. pneumoniae samples (n = 20), the median (IQR; range) CSF S. pneumoniae bacterial load was 1.1 × 104 GE/μL (1.2 × 105; 1 to 6.1 × 106 DNA GE/μL). Utilizing the optimized methodology, we estimate an extrapolated sensitivity of 90%, based on the range of CSF genome counts found in Laos. Dried CSF filter paper spots could potentially help us to better understand the epidemiology of bacterial meningitis in resource-poor settings and guide empirical treatments and vaccination policies. PMID:23738720

Substrate removal kinetics in high-rate upflow anaerobic filters packed with low-density polyethylene media treating high-strength agro-food wastewaters.

Science.gov (United States)

Rajagopal, Rajinikanth; Torrijos, Michel; Kumar, Pradeep; Mehrotra, Indu

2013-02-15

The process kinetics for two upflow anaerobic filters (UAFs) treating high strength fruit canning and cheese-dairy wastewaters as feed were investigated. The experimental unit consisted of a 10-L (effective volume) reactor filled with low-density polyethylene media. COD removal efficiencies of about 80% were recorded at the maximum OLRs of 19 and 17 g COD L(-1) d(-1) for the fruit canning and cheese-dairy wastewaters, respectively. Modified Stover-Kincannon and second-order kinetic models were applied to data obtained from the experimental studies in order to determine the substrate removal kinetics. According to Stover-Kincannon model, U(max) and K(B) values were estimated as 109.9 and 109.7 g L(-1) d(-1) for fruit canning, and 53.5 and 49.7 g L(-1) d(-1) for cheese dairy wastewaters, respectively. The second order substrate removal rate k(2(s)) was found to be 5.0 and 1.93 d(-1) respectively for fruit canning and cheese dairy wastewaters. As both these models gave high correlation coefficients (R(2) = 98-99%), they could be used in predicting the behaviour or design of the UAF. Copyright © 2012 Elsevier Ltd. All rights reserved.

Microbial stability of worm castings and sugarcane filter mud compost blended with biochar

Science.gov (United States)

Organic amendments such as worm castings and filter mud compost can provide nutrient rich substrates for enhanced plant growth. Physico-chemical and microbial stability of these substrates might be enhanced with the addition of biochar. A series of experiments was carried out to determine the stab...

Artificial hairy surfaces with a nearly perfect hydrophobic response.

Science.gov (United States)

Hsu, Shu-Hau; Sigmund, Wolfgang M

2010-02-02

A nearly perfect hydrophobic interface by dint of mimicking hairs of arthropods was achieved for the first time. These Gamma-shape artificial hairs were made via a membrane casting technique on polypropylene substrates. This extreme hydrophobicity merely arises from microstructure modification, and no further chemical treatments are needed. The ultralow adhesion to water droplets was evaluated through video assessment, and it is believed to be attributed to the mechanical response of the artificial hairs. The principle of this fabrication technique is accessible and is expected to be compatible with large-area fabrication of superhydrophobic interfaces.

Design of efficient circularly symmetric two-dimensional variable digital FIR filters.

Science.gov (United States)

Bindima, Thayyil; Elias, Elizabeth

2016-05-01

Circularly symmetric two-dimensional (2D) finite impulse response (FIR) filters find extensive use in image and medical applications, especially for isotropic filtering. Moreover, the design and implementation of 2D digital filters with variable fractional delay and variable magnitude responses without redesigning the filter has become a crucial topic of interest due to its significance in low-cost applications. Recently the design using fixed word length coefficients has gained importance due to the replacement of multipliers by shifters and adders, which reduces the hardware complexity. Among the various approaches to 2D design, transforming a one-dimensional (1D) filter to 2D by transformation, is reported to be an efficient technique. In this paper, 1D variable digital filters (VDFs) with tunable cut-off frequencies are designed using Farrow structure based interpolation approach, and the sub-filter coefficients in the Farrow structure are made multiplier-less using canonic signed digit (CSD) representation. The resulting performance degradation in the filters is overcome by using artificial bee colony (ABC) optimization. Finally, the optimized 1D VDFs are mapped to 2D using generalized McClellan transformation resulting in low complexity, circularly symmetric 2D VDFs with real-time tunability.

Waste to wealth concept: Disposable RGO filter paper for flexible temperature sensor applications

Science.gov (United States)

Neella, Nagarjuna; Kedambaimoole, Vaishakh; Gaddam, Venkateswarlu; Nayak, M. M.; Rajanna, K.

2018-04-01

We have developed a flexible reduced graphene oxide (RGO) temperature sensor on filter paper based cellulose substrate using vacuum filtration method. One of the most commonly used synthesized methods for RGO thin films is vacuum filtration process. It has several advantages such as simple operation and good controllability. The structural analysis was carried out by FE-SEM, in which the surface morphology images confirm the formation of RGO nanostructures on the filter paper substrate. It was observed that the pores of the filter paper were completely filled with the RGO material during the filtration process, subsequently the formation of continuous RGO thin films. As a results, the RGO films exhibits a piezoresistive property. The resulted RGO based films on the filter paper reveals the semiconducting behavior having sensitivity of 0.278 Ω /°C and negative temperature coefficient (NTC) about -0.00254 Ω/ Ω / °C. Thus, we demonstrate a simplified way for the fabrication of RGO films on filter paper that possesses better and easier measurable macroscopic electrical properties. Our approach is for easy way of electronics, cost-effective and environment friendly fabrication route for flexible conducting graphene films on filter paper. This will enable for the potential applications in flexible electronics in various fields including biomedical, automobile and aerospace engineering.

Reef Development on Artificial Patch Reefs in Shallow Water of Panjang Island, Central Java

Science.gov (United States)

Munasik; Sugiyanto; Sugianto, Denny N.; Sabdono, Agus

2018-02-01

Reef restoration methods are generally developed by propagation of coral fragments, coral recruits and provide substrate for coral attachment using artificial reefs (ARs). ARs have been widely applied as a tool for reef restoration in degraded natural reefs. Successful of coral restoration is determined by reef development such as increasing coral biomass, natural of coral recruits and fauna associated. Artificial Patch Reefs (APRs) is designed by combined of artificial reefs and coral transplantation and constructed by modular circular structures in shape, were deployed from small boats by scuba divers, and are suitable near natural reefs for shallow water with low visibility of Panjang Island, Central Java. Branching corals of Acropora aspera, Montipora digitata and Porites cylindrica fragments were transplanted on to each module of two units of artificial patch reefs in different periods. Coral fragments of Acropora evolved high survival and high growth, Porites fragments have moderate survival and low growth, while fragment of Montipora show in low survival and moderate growth. Within 19 to 22 months of APRs deployment, scleractinian corals were recruited on the surface of artificial patch reef substrates. The most recruits abundant was Montastrea, followed by Poritids, Pocilloporids, and Acroporids. We conclude that artificial patch reefs with developed by coral fragments and natural coral recruitment is one of an alternative rehabilitation method in shallow reef with low visibility.

Parallel processing for artificial intelligence 1

CERN Document Server

Kanal, LN; Kumar, V; Suttner, CB

1994-01-01

Parallel processing for AI problems is of great current interest because of its potential for alleviating the computational demands of AI procedures. The articles in this book consider parallel processing for problems in several areas of artificial intelligence: image processing, knowledge representation in semantic networks, production rules, mechanization of logic, constraint satisfaction, parsing of natural language, data filtering and data mining. The publication is divided into six sections. The first addresses parallel computing for processing and understanding images. The second discus

Report on the quality control study NAT-7 for the determination of trace and minor elements in dust artificially loaded on air filters

International Nuclear Information System (INIS)

Bleise, A.; Smodis, A.

2002-02-01

A quality control study was organized on two air filters artificially loaded with urban dust. One dust material was collected from the air intake ducts of the Vienna General Hospital, the second material was collected from the main ventilation shaft of a road tunnel in Prague. 49 laboratories from 40 countries participated in the study, providing 53 sets of results. The following analytical methods were used: neutron activation analysis (NAA), inductive coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS), particle induced X-ray emission spectrometry (PDCE), atomic absorption spectrometry (AAS), and X-ray fluorescence spectrometry (XRF). The results were evaluated following the standard LEA procedures for (1) an interlaboratory comparison exercise and (2) a proficiency test using established target values. For the air filter sample V, 754 laboratory mean values for 38 elements were reported. More than 4 mean values were obtained for 26 measurands and these were statistically evaluated. Only 10 % 71 values) of the results were detected as outliers by the statistical data evaluation. The results and statistical parameters are listed in the appendices I and II. The results were also evaluated as a proficiency test using established target values. Precision and accuracy criteria were applied to 15 elements. 534 laboratory mean values were reported for those elements, 114 values (20%) did not pass the set proficiency test criteria. The individual laboratory results are listed in appendix IV. For the air filter sample P, 694 laboratory mean values for 38 elements were reported. More than 4 mean values were obtained for 26 measurands and these were statistically evaluated. Only 9% (60 values) of the results were detected as outliers by the statistical data evaluation. The results and statistical parameters are listed in the appendices I and II. The results were also evaluated as a proficiency test using target values

Swarm Intelligence for Optimizing Hybridized Smoothing Filter in Image Edge Enhancement

Science.gov (United States)

Rao, B. Tirumala; Dehuri, S.; Dileep, M.; Vindhya, A.

In this modern era, image transmission and processing plays a major role. It would be impossible to retrieve information from satellite and medical images without the help of image processing techniques. Edge enhancement is an image processing step that enhances the edge contrast of an image or video in an attempt to improve its acutance. Edges are the representations of the discontinuities of image intensity functions. For processing these discontinuities in an image, a good edge enhancement technique is essential. The proposed work uses a new idea for edge enhancement using hybridized smoothening filters and we introduce a promising technique of obtaining best hybrid filter using swarm algorithms (Artificial Bee Colony (ABC), Particle Swarm Optimization (PSO) and Ant Colony Optimization (ACO)) to search for an optimal sequence of filters from among a set of rather simple, representative image processing filters. This paper deals with the analysis of the swarm intelligence techniques through the combination of hybrid filters generated by these algorithms for image edge enhancement.

Biological filters: their applications and yields; Filtros biologicos: sus aplicaciones y rendimientos

Energy Technology Data Exchange (ETDEWEB)

Barcelon, S.; Terrasa Diaz, M.; Frau Gene, C. [Empresa Municipal de Aguas Alcantarillado, S.A., Mallorca (Spain)

1995-06-01

The system of filtering gases resulting from the treatment of urban residual waters, by the compost substrate and obtaining more than acceptable yields, is presented in this article from the point of view of getting to know certain possible application, as well as the evolution of the substrate condition over time. (Author) 6 refs.

UWB Bandpass Filter with Ultra-wide Stopband based on Ring Resonator

Science.gov (United States)

Kazemi, Maryam; Lotfi, Saeedeh; Siahkamari, Hesam; Mohammadpanah, Mahmood

2018-04-01

An ultra-wideband (UWB) bandpass filter with ultra-wide stopband based on a rectangular ring resonator is presented. The filter is designed for the operational frequency band from 4.10 GHz to 10.80 GHz with an ultra-wide stopband from 11.23 GHz to 40 GHz. The even and odd equivalent circuits are used to achieve a suitable analysis of the proposed filter performance. To verify the design and analysis, the proposed bandpass filter is simulated using full-wave EM simulator Advanced Design System and fabricated on a 20mil thick Rogers_RO4003 substrate with relative permittivity of 3.38 and a loss tangent of 0.0021. The proposed filter behavior is investigated and simulation results are in good agreement with measurement results.

Artificial engineering of secondary lymphoid organs.

Science.gov (United States)

Tan, Jonathan K H; Watanabe, Takeshi

2010-01-01

Secondary lymphoid organs such as spleen and lymph nodes are highly organized immune structures essential for the initiation of immune responses. They display distinct B cell and T cell compartments associated with specific stromal follicular dendritic cells and fibroblastic reticular cells, respectively. Interweaved through the parenchyma is a conduit system that distributes small antigens and chemokines directly to B and T cell zones. While most structural aspects between lymph nodes and spleen are common, the entry of lymphocytes, antigen-presenting cells, and antigen into lymphoid tissues is regulated differently, reflecting the specialized functions of each organ in filtering either lymph or blood. The overall organization of lymphoid tissue is vital for effective antigen screening and recognition, and is a feature which artificially constructed lymphoid organoids endeavor to replicate. Synthesis of artificial lymphoid tissues is an emerging field that aims to provide therapeutic application for the treatment of severe infection, cancer, and age-related involution of secondary lymphoid tissues. The development of murine artificial lymphoid tissues has benefited greatly from an understanding of organogenesis of lymphoid organs, which has delineated cellular and molecular elements essential for the recruitment and organization of lymphocytes into lymphoid structures. Here, the field of artificial lymphoid tissue engineering is considered including elements of lymphoid structure and development relevant to organoid synthesis. (c) 2010 Elsevier Inc. All rights reserved.

Label-free visualization of ultrastructural features of artificial synapses via cryo-EM.

Science.gov (United States)

Gopalakrishnan, Gopakumar; Yam, Patricia T; Madwar, Carolin; Bostina, Mihnea; Rouiller, Isabelle; Colman, David R; Lennox, R Bruce

2011-12-21

The ultrastructural details of presynapses formed between artificial substrates of submicrometer silica beads and hippocampal neurons are visualized via cryo-electron microscopy (cryo-EM). The silica beads are derivatized by poly-d-lysine or lipid bilayers. Molecular features known to exist at presynapses are clearly present at these artificial synapses, as visualized by cryo-EM. Key synaptic features such as the membrane contact area at synaptic junctions, the presynaptic bouton containing presynaptic vesicles, as well as microtubular structures can be identified. This is the first report of the direct, label-free observation of ultrastructural details of artificial synapses.

Coral colonisation of an artificial reef in a turbid nearshore environment, Dampier Harbour, western Australia.

Directory of Open Access Journals (Sweden)

David Blakeway

Full Text Available A 0.6 hectare artificial reef of local rock and recycled concrete sleepers was constructed in December 2006 at Parker Point in the industrial port of Dampier, western Australia, with the aim of providing an environmental offset for a nearshore coral community lost to land reclamation. Corals successfully colonised the artificial reef, despite the relatively harsh environmental conditions at the site (annual water temperature range 18-32°C, intermittent high turbidity, frequent cyclones, frequent nearby ship movements. Coral settlement to the artificial reef was examined by terracotta tile deployments, and later stages of coral community development were examined by in-situ visual surveys within fixed 25 x 25 cm quadrats on the rock and concrete substrates. Mean coral density on the tiles varied from 113 ± 17 SE to 909 ± 85 SE per m(2 over five deployments, whereas mean coral density in the quadrats was only 6.0 ± 1.0 SE per m(2 at eight months post construction, increasing to 24.0 ± 2.1 SE per m(2 at 62 months post construction. Coral taxa colonising the artificial reef were a subset of those on the surrounding natural reef, but occurred in different proportions--Pseudosiderastrea tayami, Mycedium elephantotus and Leptastrea purpurea being disproportionately abundant on the artificial reef. Coral cover increased rapidly in the later stages of the study, reaching 2.3 ± 0.7 SE % at 62 months post construction. This study indicates that simple materials of opportunity can provide a suitable substrate for coral recruitment in Dampier Harbour, and that natural colonisation at the study site remains sufficient to initiate a coral community on artificial substrate despite ongoing natural and anthropogenic perturbations.

Tunable bandpass filter based on partially magnetized ferrite LTCC with embedded windings for SoP applications

KAUST Repository

Arabi, Eyad A.; Ghaffar, Farhan A.; Shamim, Atif

2015-01-01

to the previously reported filters. A simulation strategy that uses full permeability tensor with arbitrarily directed magnetic fields has been used to model the filter on a partially magnetized ferrite substrate. Special attention has also been paid to approximate

Analysis of signals propagating in a phononic crystal PZT layer deposited on a silicon substrate.

Science.gov (United States)

Hladky-Hennion, Anne-Christine; Vasseur, Jérôme; Dubus, Bertrand; Morvan, Bruno; Wilkie-Chancellier, Nicolas; Martinez, Loïc

2013-12-01

The design of a stop-band filter constituted by a periodically patterned lead zirconate titanate (PZT) layer, polarized along its thickness, deposited on a silicon substrate and sandwiched between interdigitated electrodes for emission/reception of guided elastic waves, is investigated. The filter characteristics are theoretically evaluated by using finite element simulations: dispersion curves of a patterned PZT layer with a specific pattern geometry deposited on a silicon substrate present an absolute stop band. The whole structure is modeled with realistic conditions, including appropriate interdigitated electrodes to propagate a guided mode in the piezoelectric layer. A robust method for signal analysis based on the Gabor transform is applied to treat transmitted signals; extract attenuation, group delays, and wave number variations versus frequency; and identify stop-band filter characteristics.

Non-uniform cosine modulated filter banks using meta-heuristic algorithms in CSD space

Directory of Open Access Journals (Sweden)

Shaeen Kalathil

2015-11-01

Full Text Available This paper presents an efficient design of non-uniform cosine modulated filter banks (CMFB using canonic signed digit (CSD coefficients. CMFB has got an easy and efficient design approach. Non-uniform decomposition can be easily obtained by merging the appropriate filters of a uniform filter bank. Only the prototype filter needs to be designed and optimized. In this paper, the prototype filter is designed using window method, weighted Chebyshev approximation and weighted constrained least square approximation. The coefficients are quantized into CSD, using a look-up-table. The finite precision CSD rounding, deteriorates the filter bank performances. The performances of the filter bank are improved using suitably modified meta-heuristic algorithms. The different meta-heuristic algorithms which are modified and used in this paper are Artificial Bee Colony algorithm, Gravitational Search algorithm, Harmony Search algorithm and Genetic algorithm and they result in filter banks with less implementation complexity, power consumption and area requirements when compared with those of the conventional continuous coefficient non-uniform CMFB.

Measurement of artificial radioactivity in the atmosphere at Ottawa, Canada

Energy Technology Data Exchange (ETDEWEB)

Terentiuk, F

1958-01-01

In recent years there has been considerable interest in the artificial radioactivity in the atmosphere originating from atomic and thermonuclear explosions. For the past year daily measurements of radioactivity have been made at Ottawa. The sampling times corresponded to air volumes of 425 cubic metric and 2000 cubic meters, respectively. Filters were kept for a period of 3 days before measurements were made in order to permit natural activity resulting from daughter products of radon and thoron to decay to a negligible value. Measurements of the gross beta activity from the filters were made directly with end-window Geiger tubes. Filters showing considerable initial radioactivity were measured at intervals of a few days in order to obtain the rate of decay of the activity. It was hoped that the data obtained would make it possible to fix the date of the explosion responsible for the filter activity but the fixing of dates was very uncertain.

Personality Trait and Facial Expression Filter-Based Brain-Computer Interface

Directory of Open Access Journals (Sweden)

Seongah Chin

2013-02-01

Full Text Available In this paper, we present technical approaches that bridge the gap in the research related to the use of brain-computer interfaces for entertainment and facial expressions. Such facial expressions that reflect an individual's personal traits can be used to better realize artificial facial expressions in a gaming environment based on a brain-computer interface. First, an emotion extraction filter is introduced in order to classify emotions on the basis of the users' brain signals in real time. Next, a personality trait filter is defined to classify extrovert and introvert types, which manifest as five traits: very extrovert, extrovert, medium, introvert and very introvert. In addition, facial expressions derived from expression rates are obtained by an extrovert-introvert fuzzy model through its defuzzification process. Finally, we confirm this validation via an analysis of the variance of the personality trait filter, a k-fold cross validation of the emotion extraction filter, an accuracy analysis, a user study of facial synthesis and a test case game.

Colonisation and community structure of benthic diatoms on artificial ...

African Journals Online (AJOL)

This was undertaken using tiles as artificial substrates so that we could study how the communities developed after the flood disturbance. The diatom community structure was assessed over a 28-day period following a flood event in October 2012. The Mann Whitney test indicated that there was a statistically significant ...

Effect of Pore Structure on Soot Deposition in Diesel Particulate Filter

Directory of Open Access Journals (Sweden)

Kazuhiro Yamamoto

2016-12-01

Full Text Available Nowadays, in the after-treatment of diesel exhaust gas, a diesel particulate filter (DPF has been used to trap nano-particles of the diesel soot. However, as there are more particles inside the filter, the pressure which corresponds to the filter backpressure increases, which worsens the fuel consumption rate, together with the abatement of the available torque. Thus, a filter with lower backpressure would be needed. To achieve this, it is necessary to utilize the information on the phenomena including both the soot transport and its removal inside the DPF, and optimize the filter substrate structure. In this paper, to obtain useful information for optimization of the filter structure, we tested seven filters with different porosities and pore sizes. The porosity and pore size were changed systematically. To consider the soot filtration, the particle-laden flow was simulated by a lattice Boltzmann method (LBM. Then, the flow field and the pressure change were discussed during the filtration process.

Plasma streams mixing in two-channel t-shaped magnetic filter

International Nuclear Information System (INIS)

Aksyonov, D.S.; Aksenov, I.I.; Luchaninov, A.A.; Reshetnyak, E.N.; Strel'nitskij, V.E.

2011-01-01

Ti-Al-N films were deposited by vacuum arc method. T-shaped magnetic filter with two channels was used for films preparation. Deposition was performed after aluminum and titanium separate plasma streams from two plasma sources were mixed into single one inside plasma duct having weakened magnetic field near its output. Obtained films have uniform distribution of composition and thickness on 180 mm diameter substrate surface. It was found that mixing and homogenization degree depends on nitrogen pressure, output magnetic field intensity and output- to-substrate distance. Film self-sputtering and aluminum preferential sputtering were observed for elevated negative substrate bias potentials.

Design and Analysis of a Micromachined LC Low Pass Filter For 2.4GHz Application

Science.gov (United States)

Saroj, Samruddhi R.; Rathee, Vishal R.; Pande, Rajesh S.

2018-02-01

This paper reports design and analysis of a passive low pass filter with cut-off frequency of 2.4 GHz using MEMS (Micro Electro-Mechanical Systems) technology. The passive components such as suspended spiral inductors and metal-insulator-metal (MIM) capacitor are arranged in T network form to implement LC low pass filter design. This design employs a simple approach of suspension thereby reducing parasitic losses to eliminate the performance degrading effects caused by integrating an off-chip inductor in the filter circuit proposed to be developed on a low cost silicon substrate using RF-MEMS components. The filter occupies only 2.1 mm x 0.66 mm die area and is designed using micro-strip transmission line placed on a silicon substrate. The design is implemented in High Frequency Structural Simulator (HFSS) software and fabrication flow is proposed for its implementation. The simulated results show that the design has an insertion loss of -4.98 dB and return loss of -2.60dB.

Utilizing wideband AMC structures for high-gain inkjet-printed antennas on lossy paper substrate

KAUST Repository

Cook, Benjamin Stassen

2013-01-01

Significant gain and bandwidth improvement of inkjet-printed antennas with integrated artificial magnetic conductor (AMC) is achieved by utilizing wideband ground-backed frequency selective surfaces (FSSs) to overcome the high losses of organic substrates such as paper. A microstrip-fed monopole mounted on an artificial magnetic conductor is demonstrated to improve the gain by 5 dB over previous works and exhibit much wider impedance bandwidth while maintaining a thin antenna profile and a 20% electrical size reduction. The effect of AMC bandwidth on substrate losses and the gain reduction caused by finite AMC array effects are investigated in an effort to produce high-gain, miniaturized, low-cost wearable and structure mount antennas. © 2013 IEEE.

Fate and behaviour of phenanthrene in the natural and artificial soils

International Nuclear Information System (INIS)

Hofman, Jakub; Rhodes, Angela; Semple, Kirk T.

2008-01-01

OECD artificial soil has been used routinely as a standardized substrate for soil toxicity tests. However, can be the fate, behaviour and effects of contaminants in artificial soil extrapolated to natural soils? The aim of our study was to verify this hypothesis by comparing the loss, extraction, and bioavailability of phenanthrene in three artificial and three natural soils of comparable organic carbon content. Soils were spiked with 14 C-phenanthrene and total 14 C-activity change, the fractions extracted by dichloromethane, 70% ethanol, and hydroxypropyl-β-cyclodextrin, the fraction mineralized by Pseudomonas sp., and taken up by Enchytraeus albidus were measured after 1, 14, 42, and 84 d aging. The loss, extraction, biodegradation and uptake were several times lower in the artificial than natural soils and these differences increased with increasing soil-phenanthrene contact time. These results imply that artificial soil should be used cautiously for the prediction of fate and behaviour in natural soils. - Artificial soils show substantially different fate and behaviour of phenanthrene than natural soils, which cannot be easily extrapolated or modelled

Printed Graphene Derivative Circuits as Passive Electrical Filters.

Science.gov (United States)

Sinar, Dogan; Knopf, George K

2018-02-23

The objective of this study is to inkjet print resistor-capacitor ( RC ) low pass electrical filters, using a novel water-based cellulose graphene ink, and compare the voltage-frequency and transient behavior to equivalent circuits constructed from discrete passive components. The synthesized non-toxic graphene-carboxymethyl cellulose (G-CMC) ink is deposited on mechanically flexible polyimide substrates using a customized printer that dispenses functionalized aqueous solutions. The design of the printed first-order and second-order low-pass RC filters incorporate resistive traces and interdigitated capacitors. Low pass filter characteristics, such as time constant, cut-off frequency and roll-off rate, are determined for comparative analysis. Experiments demonstrate that for low frequency applications (graphene derivative circuits performed as well as the circuits constructed from discrete resistors and capacitors for both low pass filter and RC integrator applications. The impact of mechanical stress due to bending on the electrical performance of the flexible printed circuits is also investigated.

Printed Graphene Derivative Circuits as Passive Electrical Filters

Directory of Open Access Journals (Sweden)

Dogan Sinar

2018-02-01

Full Text Available The objective of this study is to inkjet print resistor-capacitor (RC low pass electrical filters, using a novel water-based cellulose graphene ink, and compare the voltage-frequency and transient behavior to equivalent circuits constructed from discrete passive components. The synthesized non-toxic graphene-carboxymethyl cellulose (G-CMC ink is deposited on mechanically flexible polyimide substrates using a customized printer that dispenses functionalized aqueous solutions. The design of the printed first-order and second-order low-pass RC filters incorporate resistive traces and interdigitated capacitors. Low pass filter characteristics, such as time constant, cut-off frequency and roll-off rate, are determined for comparative analysis. Experiments demonstrate that for low frequency applications (<100 kHz the printed graphene derivative circuits performed as well as the circuits constructed from discrete resistors and capacitors for both low pass filter and RC integrator applications. The impact of mechanical stress due to bending on the electrical performance of the flexible printed circuits is also investigated.

Decapod crustaceans associated with an artificial reef (Adriatic Sea

Directory of Open Access Journals (Sweden)

A. SANTELLI

2013-10-01

Full Text Available The aim of this study is to increase the knowledge on the distribution of decapod crustaceans associated with an artificial reef positioned on sandy-mud bottoms in the central Adriatic Sea. The reef is constituted of concrete modules assembled in pyramids and concrete poles. Hard and soft bottom samples were collected from 2001, just after reef construction, to 2005 (4 surveys per year. Regarding the soft seabed, three sites close to a pyramid, three inside the reef area at a distance of 10-15 m from the structures, and three 200 m outside the reef (control sites were randomly sampled during each survey. At the same time, three pyramids (vertical and horizontal walls and three poles were also investigated. After taxonomical analysis, decapod crustaceans were analysed using abundance and species richness. Sites and years were compared using a balanced, fixed effect, 2-way ANOVA and PERMANOVA. In addition, SIMPER analysis was performed to identify those species typifying each community inhabiting both the soft bottom and the artificial substrates. The results showed that the artificial reef induced an increase in both abundance and diversity of the decapods of the natural habitat. In fact, man-made substrates may offer new available space for biological colonization and allow the settlement of new species usually living on hard bottoms, thus increasing the complexity of the original benthic communities.

A 15-pole high temperature superconductor filter for radar applications

Science.gov (United States)

Yu, Xiao; Xi, Weibin; Wu, Songtao

2018-06-01

This paper presents a compact and high first harmonic frequency resonator. The characteristics of this resonator are theoretically analyzed. A highly selective 15-pole Chebyshev high temperature superconducting ultra-high frequency narrowband filter for radar applications was fabricated by using this resonator. The filter has a center frequency of 495 MHz and a fractional bandwidth of 1%. The first harmonic frequency is more than 3.3 times the fundamental frequency. The measured filter shows excellent selectivity, better than 85 dB/1 MHz skirt slopes, and more than 85 dB of rejection at 497.5 MHz from the band edge. The filter was fabricated on a 2 inch YBCO thin film with a 0.5 mm thick MgO substrate. The experimental results are consistent with the simulations.

Dracaena marginata biofilter: design of growth substrate and treatment of stormwater runoff.

Science.gov (United States)

Vijayaraghavan, K; Praveen, R S

2016-01-01

The purpose of this research was to investigate the efficiency of Dracaena marginata planted biofilters to decontaminate urban runoff. A new biofilter growth substrate was prepared using low-cost and locally available materials such as red soil, fine sand, perlite, vermiculite, coco-peat and Sargassum biomass. The performance of biofilter substrate was compared with local garden soil based on physical and water quality parameters. Preliminary analyses indicated that biofilter substrate exhibited desirable characteristics such as low bulk density (1140 kg/m(3)), high water holding capacity (59.6%), air-filled porosity (7.82%) and hydraulic conductivity (965 mm/h). Four different biofilter assemblies, with vegetated and non-vegetated systems, were examined for several artificial rain events (un-spiked and metal-spiked). Results from un-spiked artificial rain events suggested that concentrations of most of the chemical components in effluent were highest at the beginning of rain events and thereafter subsided during the subsequent rain events. Biofilter growth substrate showed superior potential over garden soil to retain metal ions such as Al, Fe, Cu, Cr, Ni, Zn, Cd and Pb during metal-spiked rain events. Significant differences were also observed between non-vegetated and vegetated biofilter assemblies in runoff quality, with the latter producing better results.

Desenvolvimento da broca-das-cucurbitáceas em diferentes tipos de substratos alimentares Development of melonworm on different feeding substrates

Directory of Open Access Journals (Sweden)

Dirceu Pratissoli

2007-12-01

Full Text Available Aspectos biológicos de Diaphania nitidalis foram estudados sob dietas natural e artificial em condições de laboratório, à temperatura de 25±1ºC, umidade relativa de 70±10% e fotofase de 14 horas. Como dieta natural foi utilizada abóbora 'Jacaré', pepino 'Japonês' e abobrinha 'Caserta' e, como artificial, a dieta utilizada em criações de Diatraea saccharalis, broca da cana-de-açúcar. As lagartas de D. nitidalis foram inoculadas nos diferentes tipos de substratos e criadas por todo o ciclo. Ocorreu diferença significativa entre a maioria dos parâmetros testados dentro dos tratamentos, sendo as dietas à base de abóbora e artificial as que proporcionaram maior potencial biótico para criação de D. nitidalis. Pela facilidade de aquisição dos ingredientes e manipulação dos insetos, a dieta artificial se torna mais eficaz para criação massal dessa espécie em laboratório.The aim of this research was to evaluate the biological behaviour of melonworm at different natural and artificial diet under laboratory conditions (25ºC, 70% RH, 14 h photofase. Squash 'Jacaré', cucumber 'Japonês' and zucchini 'Caserta' were used as natural substrates compared to na artificial diet developed for the sugarcane borer (Diatraea saccharalis. The caterpillars were inoculated in each substrate and reared for a full cycle. The biological parameters were different among treatments. An artificial diet and squash cv. Jacaré substrate showed higher performance for the multiplication of D. nitidalis. The artificial diet is recommended because it is easy to obtain the ingredients and nultiply this insect under laboratory conditions.

A Novel Approach to the Design of Passive Filters in Electric Grids

Science.gov (United States)

Filho da Costa Castro, José; Lima, Lucas Ramalho; Belchior, Fernando Nunes; Ribeiro, Paulo Fernando

2016-12-01

The design of shunt passive filters has been a topic of constant research since the 70's. Due to the lower cost, passive shunt filters are still considered a preferred option. This paper presents a novel approach for the placement and sizing of passive filters through ranking solutions based on the minimization of the total harmonic distortion (THDV) of the supply system rather than one specific bus, without neglecting the individual harmonic distortions. The developed method was implemented using Matlab/Simulink and applied to a test system. The results shown that is possible to minimize the total voltage harmonic distortion using a system approach during the filter selection. Additionally, since the method is mainly based on a heurist approach, it avoids the complexity associated with of use of advanced mathematical tools such as artificial intelligence techniques. The analyses contemplate a sinusoidal voltage utility and also the condition with background distortion utility.

Rearing the southern green stink bug using an artificial dry diet and an artificial plant Criação do percevejo-verde usando dieta artificial seca e planta artificial

Directory of Open Access Journals (Sweden)

ANTÔNIO RICARDO PANIZZI

2000-09-01

Full Text Available Laboratory and greenhouse studies were conducted with an artificial dry diet to rear nymphs, and with an artificial plant as substrate for egg laying by the southern green stink bug, Nezara viridula (L.. The artificial diet was composed of: soybean protein (15 g; potato starch (7.5 g; dextrose (7.5 g; sucrose (2.5 g; cellulose (12.5 g; vitamin mixture (niacinamide 1 g, calcium pantothenate 1 g, thiamine 0.25 g, riboflavin 0.5 g, pyridoxine 0.25 g, folic acid 0.25 g, biotin 0.02 mL, vitamin B12 1 g - added to 1,000 mL of distilled water (5.0 mL; soybean oil (20 mL; wheat germ (17.9 g; and water (30 mL. Nymphs showed normal feeding behavior when fed on the artificial diet. Nymphal development time was longer than or similar to that of nymphs fed on soybean pods. Total nymphal mortality was low (ca. 30%, both for nymphs reared on the artificial diet, and for nymphs fed on soybean pods. At adult emergence, fresh body weights were significantly (PForam conduzidos estudos em laboratório e em casa de vegetação, com uma dieta artificial seca para a criação de ninfas e com um modelo de planta artificial como substrato para a colocação de ovos por adultos do percevejo-verde, Nezara viridula (L.. Os componentes da dieta artificial foram: proteína de soja (15 g; fécula de batata (7,5 g; dextrose (7,5 g; sacarose (2,5 g; celulose (12,5 g; mistura vitamínica (niacinamida 1 g, pantotenato de cálcio 1 g, tiamina 0,25 g, riboflavina 0,5 g, piridoxina 0,25 g, ácido fólico 0,25 g, biotina 0,02 mL, vitamina B12 1 g, adicionada em 1.000 mL de água destilada (5,0 mL; óleo de soja (20 mL; germe de trigo (17,9 g; e água (30 mL. As ninfas alimentaram-se normalmente da dieta, embora o tempo de desenvolvimento tenha sido em um caso, maior, e em outro, semelhante, ao das ninfas que se alimentaram de vagens da soja. A mortalidade total das ninfas foi baixa (ca. 30%, tanto na dieta como na vagem de soja. Na emergência, os adultos apresentaram peso fresco

Low-loss interference filter arrays made by plasma-assisted reactive magnetron sputtering (PARMS) for high-performance multispectral imaging

Science.gov (United States)

Broßmann, Jan; Best, Thorsten; Bauer, Thomas; Jakobs, Stefan; Eisenhammer, Thomas

2016-10-01

Optical remote sensing of the earth from air and space typically utilizes several channels in the visible and near infrared spectrum. Thin-film optical interference filters, mostly of narrow bandpass type, are applied to select these channels. The filters are arranged in filter wheels, arrays of discrete stripe filters mounted in frames, or patterned arrays on a monolithic substrate. Such multi-channel filter assemblies can be mounted close to the detector, which allows a compact and lightweight camera design. Recent progress in image resolution and sensor sensitivity requires improvements of the optical filter performance. Higher demands placed on blocking in the UV and NIR and in between the spectral channels, in-band transmission and filter edge steepness as well as scattering lead to more complex filter coatings with thicknesses in the range of 10 - 25μm. Technological limits of the conventionally used ion-assisted evaporation process (IAD) can be overcome only by more precise and higher-energetic coating technologies like plasma-assisted reactive magnetron sputtering (PARMS) in combination with optical broadband monitoring. Optics Balzers has developed a photolithographic patterning process for coating thicknesses up to 15μm that is fully compatible with the advanced PARMS coating technology. This provides the possibility of depositing multiple complex high-performance filters on a monolithic substrate. We present an overview of the performance of recently developed filters with improved spectral performance designed for both monolithic filter-arrays and stripe filters mounted in frames. The pros and cons as well as the resulting limits of the filter designs for both configurations are discussed.

The Design of Polymer Planar Optical Triplexer with MMI Filter and Directional Coupler

Directory of Open Access Journals (Sweden)

V. Jerabek

2013-12-01

Full Text Available Optical bidirectional WDM transceiver is a key component of the Passive Optical Network of the Fiber to the Home topology. Essential parts of such transceivers are filters that combine multiplexing and demultiplexing function of optical signal (triplexing filters. In this paper we report about a design of a new planar optical multi-wavelength selective system triplexing filter, which combines a multimode interference filter with directional coupler based on the epoxy polymer SU-8 on Si/SiO2 substrate. The optical triplexing filter was designed using the Beam Propagation Method. The aim of this project was to optimize the triplexing filter optical parameters and to minimize the planar optical wavelength selective system dimensions. The multimode interference filter was used for separation of downstream optical signal in designed optoelectronic integrated WDM transceiver. The directional coupler was used for adding of upstream optical signal.

Customized broadband Sloan-filters for the JST/T250 and JAST/T80 telescopes: measurement summary

Science.gov (United States)

Brauneck, Ulf; Sprengard, Ruediger; Bourquin, Sebastien; Marín-Franch, Antonio

2018-01-01

The Centro de Estudios de Fisica del Cosmos de Aragon will conduct a photometric sky survey with two new telescopes recently set up on the Javalambre mountain in Spain: the JST/T250 is a 2.55-m telescope with a plate scale of 22.67 arc⁢sec/mm and a 3-deg-diameter field of view (FoV) and the auxiliary telescope JAST/T80 with a 82-cm primary mirror and an FoV of 2 deg diameter. A multiple CCD (9k-by-9k array size, 10-μm pixel size) mosaic camera is used in combination with filter trays or filter wheels, each containing a multitude of filters in dimensions of 101.7×96.5 mm or 106.8×106.8 mm. For this project, Schott manufactured 56 specially designed narrow band steep-edged bandpass interference filters and five broadband Sloan-filters which were completed only recently. We report here on the results of the broadband Sloan-filters with transmission bands of 324 to 400 nm (Sloan-u), 400 to 550 nm (Sloan-g), 550 to 700 nm (Sloan-r), 695 to 850 nm (Sloan-i), and 830 to 1200 nm (Sloan-z). The filters are composed of Schott filterglasses and clearglass substrates coated with interference filters and represent an improvement of broadband Sloan filters commonly used in astronomy. In spite of the absorptive elements, the filters show maximum possible transmissions achieved by magnetron sputtered filter coatings. In addition, the blocking of the filters is better than OD5 (transmission <10 to -5) in the range 250 to 1050 nm which was achieved by combining up to three substrates. A high image quality required a low transmitted wavefront error (<λ/8 locally, respectively <λ/2 globally). We report on the spectral and interferometric results measured on the filters.

8th International Workshop on Information Filtering and Retrieval

CERN Document Server

Giuliani, Alessandro; Semeraro, Giovanni

2017-01-01

This book focuses on new research challenges in intelligent information filtering and retrieval. It collects invited chapters and extended research contributions from DART 2014 (the 8th International Workshop on Information Filtering and Retrieval), held in Pisa (Italy), on December 10, 2014, and co-hosted with the XIII AI*IA Symposium on Artificial Intelligence. The main focus of DART was to discuss and compare suitable novel solutions based on intelligent techniques and applied to real-world contexts. The chapters of this book present a comprehensive review of related works and the current state of the art. The contributions from both practitioners and researchers have been carefully reviewed by experts in the area, who also gave useful suggestions to improve the quality of the book.

Dense grid of narrow bandpass filters for the JST/T250 telescope: summary of results

Science.gov (United States)

Brauneck, Ulf; Sprengard, Ruediger; Bourquin, Sebastien; Marín-Franch, Antonio

2018-01-01

On the Javalambre mountain in Spain, the Centro de Estudios de Fisica del Cosmos de Aragon has setup two telescopes, the JST/T250 and the JAST/T80. The JAST/T80 telescope integrates T80Cam, a large format, single CCD camera while the JST/T250 will mount the JPCam instrument, a 1.2Gpix camera equipped with a 14-CCD mosaic using the new large format e2v 9.2k×9.2k 10-μm pixel detectors. Both T80Cam and JPCam integrate a large number of filters in dimensions of 106.8×106.8 mm2 and 101.7×95.5 mm2, respectively. For this instrument, SCHOTT manufactured 56 specially designed steep edged bandpass interference filters, which were recently completed. The filter set consists of bandpass filters in the range between 348.5 and 910 nm and a longpass filter at 915 nm. Most of the filters have full-width at half-maximum (FWHM) of 14.5 nm and a blocking between 250 and 1050 nm with optical density of OD5. Absorptive color glass substrates in combination with interference filters were used to minimize residual reflection in order to avoid ghost images. In spite of containing absorptive elements, the filters show the maximum possible transmission. This was achieved by using magnetron sputtering for the filter coating process. The most important requirement for the continuous photometric survey is the tight tolerancing of the central wavelengths and FWHM of the filters. This insures each bandpass has a defined overlap with its neighbors. A high image quality required a low transmitted wavefront error (<λ/4 locally and <λ/2 on the whole aperture), which was achieved even by combining two or three substrates. We report on the spectral and interferometric results measured on the whole set of filters.

Alternating current line-filter based on electrochemical capacitor utilizing template-patterned graphene

OpenAIRE

Zhenkun Wu; Liyi Li; Ziyin Lin; Bo Song; Zhuo Li; Kyoung-Sik Moon; Ching-Ping Wong; Shu-Lin Bai

2015-01-01

Aluminum electrolytic capacitors (AECs) are widely used for alternating current (ac) line-filtering. However, their bulky size is becoming more and more incompatible with the rapid development of portable electronics. Here we report a scalable process to fabricate miniaturized graphene-based ac line-filters on flexible substrates at room temperature. In this work, graphene oxide (GO) is reduced by patterned metal interdigits at room temperature and used directly as the electrode material. The...

Implicit Kalman filter algorithm for nuclear reactor analysis

International Nuclear Information System (INIS)

Hassberger, J.A.; Lee, J.C.

1986-01-01

Artificial intelligence (AI) is currently the hot topic in nuclear power plant diagnostics and control. Recently, researchers have considered the use of simulation as knowledge in which faster than real-time best-estimate simulations based on first principles are tightly coupled with AI systems for analyzing power plant transients on-line. On-line simulations can be improved through a Kalman filter, a mathematical technique for obtaining the optimal estimate of a system state given the information contained in the equations of system dynamics and measurements made on the system. Filtering can be used to systemically adjust parameters of a low-order simulation model to obtain reasonable agreement between the model and actual plant dynamics. The authors present here a general Kalman filtering algorithm that derives its information of system dynamics implicitly and naturally from the discrete time step-series of state estimates available from a simulation program. Previous research has demonstrated that models adjusted on past data can be coupled with an intelligent controller to predict the future time-course of plant transients

Prediction of the thickness of the compensator filter in radiation therapy using computational intelligence

International Nuclear Information System (INIS)

Dehlaghi, Vahab; Taghipour, Mostafa; Haghparast, Abbas; Roshani, Gholam Hossein; Rezaei, Abbas; Shayesteh, Sajjad Pashootan; Adineh-Vand, Ayoub; Karimi, Gholam Reza

2015-01-01

In this study, artificial neural networks (ANNs) and adaptive neuro-fuzzy inference system (ANFIS) are investigated to predict the thickness of the compensator filter in radiation therapy. In the proposed models, the input parameters are field size (S), off-axis distance, and relative dose (D/D 0 ), and the output is the thickness of the compensator. The obtained results show that the proposed ANN and ANFIS models are useful, reliable, and cheap tools to predict the thickness of the compensator filter in intensity-modulated radiation therapy

Prediction of the thickness of the compensator filter in radiation therapy using computational intelligence

Energy Technology Data Exchange (ETDEWEB)

Dehlaghi, Vahab; Taghipour, Mostafa; Haghparast, Abbas [Department of Biomedical Engineering, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Roshani, Gholam Hossein [School of Energy, Kermanshah University of Technology, Kermanshah (Iran, Islamic Republic of); Rezaei, Abbas [Department of Electrical Engineering, Kermanshah University of Technology, Kermanshah (Iran, Islamic Republic of); Shayesteh, Sajjad Pashootan [Department of Biomedical Engineering, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Adineh-Vand, Ayoub [Department of Computer Engineering, Islamic Azad University, Kermanshah (Iran, Islamic Republic of); Department of Electrical Engineering, Razi University, Kermanshah (Iran, Islamic Republic of); Karimi, Gholam Reza, E-mail: ghkarimi@razi.ac.ir [Department of Electrical Engineering, Razi University, Kermanshah (Iran, Islamic Republic of)

2015-04-01

In this study, artificial neural networks (ANNs) and adaptive neuro-fuzzy inference system (ANFIS) are investigated to predict the thickness of the compensator filter in radiation therapy. In the proposed models, the input parameters are field size (S), off-axis distance, and relative dose (D/D{sub 0}), and the output is the thickness of the compensator. The obtained results show that the proposed ANN and ANFIS models are useful, reliable, and cheap tools to predict the thickness of the compensator filter in intensity-modulated radiation therapy.

Demand-driven biogas production in anaerobic filters

International Nuclear Information System (INIS)

Lemmer, Andreas; Krümpel, Johannes

2017-01-01

Highlights: • Feasibility of demand-driven biogas production in anaerobic filters demonstrated. • Predictable ramping up of gas production by 300–400% within one hour. • Degradation degree remained stable >92% for all substrates and operation modes. • Measure of responsiveness to sudden changes in organic loading rate introduced. • Carbon balance for demand-driven operation. - Abstract: The growth in electricity generated from renewable energy sources is posing challenges for grid stability and the need to counter balance the intermittent power supply by these sources. Biogas technology can offer such grid services by adapting biogas production to balance the demand and subsequent electricity production of the combined heat and power unit. Innovative plant designs, such as two-staged anaerobic digestion, could possibly adapt to imbalances in the electricity grid within shorter time frames than traditional continuously stirred tank reactors (CSTR). The scope of this research paper was to demonstrate the feasibility of operating an anaerobic filter for highly flexible gas production. The repeatability of this type of operation was examined to demonstrate its predictability. Based on gas production profiles, a measure of responsiveness was introduced to determine whether and how rapidly adaptations to the production process are possible. Furthermore, the influence of substrate composition was tested and finally a carbon balance was derived to evaluate operation performance. The results indicated that anaerobic filters are well suited for flexible gas production and the results were well reproduced under the conditions presented. Substrate composition was found to have no effect on increasing the rate of methane production. The pH value in the reactor did have an effect on the solubility of CO_2 and HCO_3"− and therefore marked an important parameter that determines biogas composition, especially under varying organic loading rates. The carbon balance had

Musical noise reduction using an adaptive filter

Science.gov (United States)

Hanada, Takeshi; Murakami, Takahiro; Ishida, Yoshihisa; Hoya, Tetsuya

2003-10-01

This paper presents a method for reducing a particular noise (musical noise). The musical noise is artificially produced by Spectral Subtraction (SS), which is one of the most conventional methods for speech enhancement. The musical noise is the tin-like sound and annoying in human auditory. We know that the duration of the musical noise is considerably short in comparison with that of speech, and that the frequency components of the musical noise are random and isolated. In the ordinary SS-based methods, the musical noise is removed by the post-processing. However, the output of the ordinary post-processing is delayed since the post-processing uses the succeeding frames. In order to improve this problem, we propose a novel method using an adaptive filter. In the proposed system, the observed noisy signal is used as the input signal to the adaptive filter and the output of SS is used as the reference signal. In this paper we exploit the normalized LMS (Least Mean Square) algorithm for the adaptive filter. Simulation results show that the proposed method has improved the intelligibility of the enhanced speech in comparison with the conventional method.

Microelectromechanical filter formed from parallel-connected lattice networks of contour-mode resonators

Science.gov (United States)

Wojciechowski, Kenneth E; Olsson, III, Roy H; Ziaei-Moayyed, Maryam

2013-07-30

A microelectromechanical (MEM) filter is disclosed which has a plurality of lattice networks formed on a substrate and electrically connected together in parallel. Each lattice network has a series resonant frequency and a shunt resonant frequency provided by one or more contour-mode resonators in the lattice network. Different types of contour-mode resonators including single input, single output resonators, differential resonators, balun resonators, and ring resonators can be used in MEM filter. The MEM filter can have a center frequency in the range of 10 MHz-10 GHz, with a filter bandwidth of up to about 1% when all of the lattice networks have the same series resonant frequency and the same shunt resonant frequency. The filter bandwidth can be increased up to about 5% by using unique series and shunt resonant frequencies for the lattice networks.

Sequential interrogation of multiple FBG sensors using LPG modulation and an artificial neural network

International Nuclear Information System (INIS)

Basu, Mainak; Ghorai, S K

2015-01-01

Interrogating multiple fiber Bragg gratings (FBG) requires highly sensitive spectrum scanning equipment such as optical spectrum analyzers, tunable filters, acousto-optic tunable filters etc, which are expensive, bulky and time consuming. In this paper, we present a new approach for multiple FBG sensor interrogation using long-period gratings and an artificial neural network. The reflection spectra of the multiplexed FBGs are modulated by two long period gratings separately and the modulated optical intensities were detected by two photodetectors. The outputs of the detectors are then used as input in a previously trained artificial neural network to interrogate the FBG sensors. Simulations have been performed to determine the strain and wavelength shift using two and four sensors. The interrogation system has also been demonstrated experimentally for two sensors using simply supported beams in the range of 0–350 μstrain. The proposed interrogation scheme has been found to identify the perturbed FBG, and to determine strain and wavelength shift with reasonable accuracy. (paper)

Colonization of Lutzomyia shannoni (Diptera: Psychodidae) utilizing an artificial blood feeding technique.

Science.gov (United States)

Mann, Rajinder S; Kaufman, Phillip E

2010-12-01

Laboratory colonization of hematophagous insects must include an efficient method of blood feeding, preferably by artificial means. Strict rules for obtaining animal use permits, extensive animal maintenance costs, and indirect anesthesia effects on animal health warrant the development of an artificial membrane feeding technique for sand fly colonization in laboratories. An attempt was made to colonize Lutzomyia shannoni using an artificial blood feeding membrane to replace the use of live animals commonly used for sand fly blood-feeding purposes. Lutzomyia shannoni readily fed through a pig intestine membrane exposed at an angle of 45°. However, it did not feed through a chicken skin membrane. Olfactory attractants were unable to improve blood-feeding efficiency. Plaster of Paris was the most suitable oviposition substrate. Female L. shannoni adults laid no eggs on moist sand substrate. Sand fly adults held in groups of ten or more laid higher numbers of eggs than did individually maintained sand flies. Inclusion of the L. longipalpis oviposition hormone dodecanoic acid or the presence of previously laid eggs did not stimulate L. shannoni oviposition. The average L. shannoni egg, larval, and pupal duration were 9.3, 36.7, and 17.8 days, respectively. The addition of a 20% sugar solution improved adult female longevity. Females survived longer (14.8 days) than males (11.9 days). Lutzomyia shannoni was successfully colonized in the laboratory for up to four generations using this artificial membrane technique. © 2010 The Society for Vector Ecology.

From Unnatural Amino Acid Incorporation to Artificial Metalloenzymes

KAUST Repository

Makki, Arwa A.

2016-12-04

Studies and development of artificial metalloenzymes have developed into vibrant areas of research. It is expected that artificial metalloenzymes will be able to combine the best of enzymatic and homogenous catalysis, that is, a broad catalytic scope, high selectivity and activity under mild, aqueous conditions. Artificial metalloenzyme consist of a host protein and a newly introduced artificial metal center. The host protein merely functions as ligand controlling selectivity and augmenting reactivity, while the metal center determines the reactivity. Potential applications range from catalytic production of fine chemicals and feedstock to electron transfer utilization (e.g. fuel cells, water splitting) and medical research (e.g. metabolic screening). Particularly modern asymmetric synthesis is expected to benefit from a successful combination of the power of biocatalysis (substrate conversion via multi-step or cascade reactions, potentially immortal catalyst, unparalleled selectivity and optimization by evolutionary methods) with the versatility and mechanism based optimization methods of homogeneous catalysis. However, so far systems are either limited in structural diversity (biotin-avidin technology) or fail to deliver the selectivities expected (covalent approaches). This thesis explores a novel strategy based on the site-selective incorporation of unnatural, metal binding amino acids into a host protein. The unnatural amino acids can either serve directly as metal binding centers can be used as anchoring points for artificial metallo-cofactors. The identification expression, purification and modification of a suitable protein scaffolds is fundamental to successfully develop this field. Chapter 2 and 3 detail a rational approach leading to a highly engineered host protein. Starting with fluorescent proteins, which combine high thermal and pH stability, high expression yields, and fluorescence for ease of quantification and monitoring an efficient and fast

Performance evaluation of 3-D enhancement filters for detection of lung cancer from 3-D chest X-ray CT images

International Nuclear Information System (INIS)

Shimizu, Akinobu; Hagai, Makoto; Toriwaki, Jun-ichiro; Hasegawa, Jun-ichi.

1995-01-01

This paper evaluates the performance of several three dimensional enhancement filters used in procedures for detecting lung cancer shadows from three dimensional (3D) chest X-ray CT images. Two dimensional enhancement filters such as Min-DD filter, Contrast filter and N-Quoit filter have been proposed for enhancing cancer shadows in conventional 2D X-ray images. In this paper, we extend each of these 2D filters to a 3D filter and evaluate its performance experimentally by using CT images with artificial and true lung cancer shadows. As a result, we find that these 3D filters are effective for determining the position of a lung cancer shadow in a 3D chest CT image, as compared with the simple procedure such as smoothing filter, and that the performance of these filters become lower in the hilar area due to the influence of the vessel shadows. (author)

EcoBot-II: An artificial agent with a natural metabolism

Directory of Open Access Journals (Sweden)

Chris Melhuish

2008-11-01

Full Text Available In this paper we report the development of the robot EcoBot-II, which exhibits a primitive form of artificial symbiosis. Microbial Fuel Cells (MFCs were used as the onboard energy supply, which consisted of bacterial cultures from sewage sludge and employed oxygen from free air for oxidation at the cathode. EcoBot-II was able to perform sensing, information processing, communication and actuation when fed (amongst other substrates with flies. This is the first robot in the world, to utilise unrefined substrate, oxygen from free air and exhibit four different types of behaviour.

Ion Permeability of Artificial Membranes Evaluated by Diffusion Potential and Electrical Resistance Measurements

Science.gov (United States)

Shlyonsky, Vadim

2013-01-01

In the present article, a novel model of artificial membranes that provides efficient assistance in teaching the origins of diffusion potentials is proposed. These membranes are made of polycarbonate filters fixed to 12-mm plastic rings and then saturated with a mixture of creosol and "n"-decane. The electrical resistance and potential…

Bioconcentration of artificial radionuclides in edible mushrooms: in situ and in vitro studies

Energy Technology Data Exchange (ETDEWEB)

Dementyev, Dmitry V.; Manukovsky, Nikolai S.; Bolsunovsky, Alexander Ya.; Alexandrova, Yuliyana V. [Institute of Biophysics, Siberian Branch of the Russian Academy of Sciences, 660036, Krasnoyarsk (Russian Federation)

2014-07-01

grown on the soil-like substrate showed that accumulation of Am-241 from solution by mycelium of Pleurotus ostreatus and Neonothopanus nimbi reached 97%. Hence, these mushroom species can be used for bioremediation of solutions contaminated by radionuclides. The substrates prepared from Yenisei flood plain soils and bottom sediments, which contained Co-60, Cs-137, and Eu-152 and were also supplemented with Am-241, were used to grow fruiting bodies of P. ostreatus. The analysis showed that the fruiting bodies accumulated only Cs-137 and Am-241. The highest CF of Cs-137 by P. ostreatus grown on the sediment-based substrate was an order of magnitude higher than the CF of Cs-137 by the mushrooms grown on the soil-based substrate (0.1 vs. 0.008), due to differences in Cs-137 bioavailability in soil and sediment. Also, the CF of Am-241 was twice higher in the fruiting bodies grown on the sediment-based substrate than in those grown on the soil-based substrate (0.005 vs. 0.0026). Analysis of the CFs showed that under natural conditions, accumulation rates of Cs-137 by mushrooms were an order of magnitude higher than those of U-238. Under laboratory conditions, accumulation of Cs-137 in fruiting bodies was an order of magnitude greater than accumulation of Am-241, a transuranium radionuclide. The ability of mushrooms to accumulate artificial radionuclides makes them good candidates for bioremediation of contaminated solutions and soils. (authors)

Comparative toxicity in earthworms Eisenia fetida and Lumbricus terrestris exposed to cadmium nitrate using artificial soil and filter paper protocols

Energy Technology Data Exchange (ETDEWEB)

Fitzpatrick, L.C.; Goven, A.J. [Univ. of North Texas, Denton, TX (United States); Muratti-Ortiz, J.F. [City of Denton Water/Wastewater Laboratory, TX (United States); Venables, B.J. [TRAC Laboratories Inc., Denton, TX (United States)

1996-07-01

Earthworms are ideal soil organisms for use in terrestrial ecotoxicology. As such, several earthworm protocols have been developed for testing toxic potential of chemicals and contaminated soils. Of these, the 48-h filter paper contact (FP) and the 14-d artificial soil exposure (AS) protocols, using mortality (LC50) as the toxic endpoint and Eisenia fetida as the test species, have received the most attention, with the latter being adopted by both OECD and EEC in Europe and the Environmental Protection Agency (USEPA) in the United States. Although the FP technique, adopted by EEC, provides for inexpensive reproducible toxicity screening for chemicals (i.e. establishing relative toxicities), it has been criticized for lacking the ecotoxicological relevance of the AS protocol. Choice of earthworm species for laboratory testing also has been controversial. The manure worm, E. fetida, is criticized for not being sufficiently sensitive to chemicals or representative of {open_quotes}typical{close_quotes} earthworms. Lumbricus terrestris and Apporectodea caliginosa have been suggested as more sensitive and ecologically relevant earthworms by Dean-Ross and Martin, respectively. This paper compares the AS and FP protocols in assessing toxicity of cadminum to L. terrestris and E. fetida using LC50s and LC50s. 19 refs., 2 tabs.

Thin film soft X-ray absorption filters

International Nuclear Information System (INIS)

Stattin, H.

1992-11-01

This report discusses the composition, reparation and performance of soft x-ray transmission filters for a water window soft x-ray microscope. Unbacked thin films of aluminum, silver and vanadium/aluminum were made by evaporation on a substrate from which they were released. Measured transmittances agree reasonably well with calculations. The report also includes some related theory and discussions about film preparation methods, film contamination and evaluation methods. 33 refs

Optical Protection Filters for Harmful Laser Beams and UV Radiation

Science.gov (United States)

Azim M., Osama A.

2007-02-01

Due to the rapid growth of radiation protection applications in various devices and instruments, it is essential to use suitable filters for eye protection of the personal working in the radiation field. Different protection filters were produced to protect from four laser beam wavelengths (at 532nm, 632.8nm, 694nm and 1064nm) and block three UV bands (UVA, UVB, and UVC). The design structure of the required dielectric multilayer filters used optical thin film technology. The computer analyses of the multilayer filter formulas were prepared using Macleod Software for the production filter processes. The deposition technique was achieved on optical substrates (Glass BK-7 and Infrasil 301) by dielectric material combinations including Dralo (mixture of oxides TiO2/Al2O3), and Lima (mixture of oxides SiO2/Al2O3); deposition by an electron beam gun. The output transmittance curves for both theoretical and experimental values of all filters are presented. To validate the suitability for use in a `real world', rather than laboratory test application, full environmental assessment was also carried out. These filters exhibited high endurance after exposing them to the durability tests (adhesion, abrasion resistance and humidity) according to military standards MIL-C-675C and MIL-C-48497A.

Optical Protection Filters for Harmful Laser Beams and UV Radiation

International Nuclear Information System (INIS)

Azim M, Osama A.

2007-01-01

Due to the rapid growth of radiation protection applications in various devices and instruments, it is essential to use suitable filters for eye protection of the personal working in the radiation field. Different protection filters were produced to protect from four laser beam wavelengths (at 532nm, 632.8nm, 694nm and 1064nm) and block three UV bands (UVA, UVB, and UVC). The design structure of the required dielectric multilayer filters used optical thin film technology. The computer analyses of the multilayer filter formulas were prepared using Macleod Software for the production filter processes. The deposition technique was achieved on optical substrates (Glass BK-7 and Infrasil 301) by dielectric material combinations including Dralo (mixture of oxides TiO2/Al2O3), and Lima (mixture of oxides SiO2/Al2O3); deposition by an electron beam gun. The output transmittance curves for both theoretical and experimental values of all filters are presented. To validate the suitability for use in a 'real world', rather than laboratory test application, full environmental assessment was also carried out. These filters exhibited high endurance after exposing them to the durability tests (adhesion, abrasion resistance and humidity) according to military standards MIL-C-675C and MIL-C-48497A

Assay of hybrid ribonuclease using a membrane filter-immobilized synthetic hybrid: application to the human leukemic cell

International Nuclear Information System (INIS)

Papaphilis, A.D.; Kamper, E.F.

1985-01-01

A method for assaying hybrid ribonuclease has been devised which utilizes as substrate the synthetic hybrid [ 3 H]polyriboadenylic acid [poly(rA)]:polydeoxythymidylic acid [poly(dT)] immobilized on the solid matrix of nitrocellulose filters. The hybridization on filter of [ 3 H]poly(rA) to poly(dT) has been explored in terms of efficacy of the process and the response of the product to RNase H. A pulse of uv irradiation of poly(dT) while in dry state on the filter increased its firm binding to the filter in a concentration-dependent manner, resulting in a concomitant increase of the yield of hybrid formation. The filter-immobilized hybrid was 95% resistant to RNase A but sensitive to RNase H. When stored in toluene in the cold the hybrid maintained its stability for over 6 months, as judged by its resistance to RNase A. The method offers a number of advantages over assays that use solution hybrids as substrates and was readily applicable in the screening of leukemic patients, in the leukocytes of which it has demonstrated increased RNase H levels

Design and analysis of planar spiral resonator bandstop filter for microwave frequency

Science.gov (United States)

Motakabber, S. M. A.; Shaifudin Suharsono, Muhammad

2017-11-01

In microwave frequency, a spiral resonator can act as either frequency reject or acceptor circuits. A planar logarithmic spiral resonator bandstop filter has been developed based on this property. This project focuses on the rejection property of the spiral resonator. The performance analysis of the exhibited filter circuit has been performed by using scattering parameters (S-parameters) technique in the ultra-wideband microwave frequency. The proposed filter is built, simulated and S-parameters analysis have been accomplished by using electromagnetic simulation software CST microwave studio. The commercial microwave substrate Taconic TLX-8 has been used to build this filter. Experimental results showed that the -10 dB rejection bandwidth of the filter is 2.32 GHz and central frequency is 5.72 GHz which is suitable for ultra-wideband applications. The proposed design has been full of good compliance with the simulated and experimental results here.

Design of HTS filter for GSM-R communication system

Science.gov (United States)

Cui, Hongyu; Ji, Laiyun

2018-04-01

High-temperature superconducting materials with its excellent performance have increasingly been valued by industries, especially in the field of electronic information. The superconducting material has almost zero surface resistance, and the filter made of it has the characteristics of low insertion loss, high edge steepness and good out-of-band rejection. It has higher selectivity for the desired signal and thus less interference from adjacent channels Signal interference, and noise reduction coefficient can improve the ability to detect weak signals. This design is suitable for high temperature superconducting filter of GSM-R communication system, which can overcome many shortcomings of the traditional GSM-R. The filter is made of DyBCO, a high temperature superconducting thin film material based on magnesium oxide (MgO) substrate with the dielectric constant of 9.7, the center frequency at 887.5MHz, bandwidth of 5MHz.

Species sorting during biofilm assembly by artificial substrates deployed in a cold seep system

KAUST Repository

Zhang, Wei Peng

2014-10-17

Studies focusing on biofilm assembly in deep-sea environments are rarely conducted. To examine the effects of substrate type on microbial community assembly, biofilms were developed on different substrates for different durations at two locations in the Red Sea: in a brine pool and in nearby bottom water (NBW) adjacent to the Thuwal cold seep II. The composition of the microbial communities in 51 biofilms and water samples were revealed by classification of pyrosequenced 16S rRNA gene amplicons. Together with the microscopic characteristics of the biofilms, the results indicate a stronger selection effect by the substrates on the microbial assembly in the brine pool compared with the NBW. Moreover, the selection effect by substrate type was stronger in the early stages compared with the later stages of the biofilm development. These results are consistent with the hypotheses proposed in the framework of species sorting theory, which states that the power of species sorting during microbial community assembly is dictated by habitat conditions, duration and the structure of the source community. Therefore, the results of this study shed light on the control strategy underlying biofilm-associated marine fouling and provide supporting evidence for ecological theories important for understanding the formation of deep-sea biofilms.

Species sorting during biofilm assembly by artificial substrates deployed in a cold seep system

KAUST Repository

Zhang, Wei Peng; Wang, Yong; Tian, Ren Mao; Bougouffa, Salim; Yang, Bo; Cao, Hui Luo; Zhang, Gen; Wong, Yue Him; Xu, Wei; Batang, Zenon B.; Al-Suwailem, Abdulaziz M.; Zhang, Xixiang; Qian, Pei-Yuan

2014-01-01

Studies focusing on biofilm assembly in deep-sea environments are rarely conducted. To examine the effects of substrate type on microbial community assembly, biofilms were developed on different substrates for different durations at two locations in the Red Sea: in a brine pool and in nearby bottom water (NBW) adjacent to the Thuwal cold seep II. The composition of the microbial communities in 51 biofilms and water samples were revealed by classification of pyrosequenced 16S rRNA gene amplicons. Together with the microscopic characteristics of the biofilms, the results indicate a stronger selection effect by the substrates on the microbial assembly in the brine pool compared with the NBW. Moreover, the selection effect by substrate type was stronger in the early stages compared with the later stages of the biofilm development. These results are consistent with the hypotheses proposed in the framework of species sorting theory, which states that the power of species sorting during microbial community assembly is dictated by habitat conditions, duration and the structure of the source community. Therefore, the results of this study shed light on the control strategy underlying biofilm-associated marine fouling and provide supporting evidence for ecological theories important for understanding the formation of deep-sea biofilms.

Customized broadband sloan-filters for the JST/T250 and JAST/T80 telescopes: summary of results

Science.gov (United States)

Brauneck, U.; Sprengard, R.; Bourquin, S.; Marín-Franch, A.

2017-09-01

The Centro de Estudios de Fisica del Cosmos de Aragon (CEFCA) will conduct a photometric sky survey with 2 new telescopes recently setup on the Javalambre mountain in Spain: the JST/T250 is a 2.55m telescope with a plate scale of 22.67"/mm and a 3° diameter field of view (FoV) and the auxiliary telescope JAST/T80 with a 82cm primary mirror and a FoV of 2 deg diameter. A multiple CCD (9k-by-9k array size, 10μm pixel size) mosaic camera is used in combination with filter trays or filter wheels, each containing a multitude of filters in dimensions of 101.7x96.5mm or 106.8x106.8mm. For this project, SCHOTT manufactured 56 specially designed narrow band steep edged bandpass interference filters and 5 broadband sloan-filters which were completed only recently. We report here on the results of the broadband sloanfilters with transmission bands of 324-400nm (sloan-u), 400-550nm (sloan-g), 550-700nm (sloan-r), 695-850nm (sloan-i) and 830-1200nm (sloan-z). The filters are composed of SCHOTT filterglasses and clearglass substrates coated with interference filters and represent an improvement of broadband sloan filters commonly used in astronomy. Inspite of the absorptive elements, the filters show maximum possible transmissions achieved by magnetron sputtered filter coatings. In addition the blocking of the filters is better than OD5 in the range 250-1050nm. A high image quality required a low transmitted wavefront error (<λ/8 locally, respectively <λ/2 globally) which was achieved by combining up to 2 substrates. We report on the spectral and interferometric results measured on the filters.

Ultranarrow-bandwidth filter based on a thermal EIT medium.

Science.gov (United States)

Wang, Gang; Wang, Yu-Sheng; Huang, Emily Kay; Hung, Weilun; Chao, Kai-Lin; Wu, Ping-Yeh; Chen, Yi-Hsin; Yu, Ite A

2018-05-21

We present high-contrast electromagnetically-induced-transparency (EIT) spectra in a heated vapor cell of single isotope 87 Rb atoms. The EIT spectrum has both high resonant transmission up to 67% and narrow linewidth of 1.1 MHz. We get rid of the possible amplification resulted from the effects of amplification without population inversion and four-wave mixing. Therefore, this high transmitted light is not artificial. The theoretical prediction of the probe transmission agrees well with the data and the experimental parameters can be derived reasonably from the model. Such narrow and high-contrast spectral profile can be employed as a high precision bandpass filter, which provides a significant advantage in terms of stability and tunability. The central frequency tuning range of the filter is larger than 100 MHz with out-of-band blocking ≥15 dB. This bandpass filter can effectively produce light fields with subnatural linewidth. Nonlinearity associating with the narrow-linewidth and high-contrast EIT profile can be very useful in the applications utilizing the EIT effect.

A dense grid of narrow bandpass steep edge filters for the JST/T250 telescope: summary of results

Science.gov (United States)

Brauneck, U.; Sprengard, R.; Bourquin, S.; Marín-Franch, A.

2017-09-01

On the Javalambre mountain in Spain, the Centro de Estudios de Fisica del Cosmos de Aragon (CEFCA) has setup a new wide field telescope, the JST/T250: a 2.55 m telescope with a plate scale of 22.67"/mm and a 3° diameter field of view. To conduct a photometric sky survey, a large format mosaic camera made of 14 individual CCDs is used in combination with filter trays containing 14 filters each of theses 101.7 x 96.5 mm in size. For this instrument, SCHOTT manufactured 56 specially designed steep edged bandpass interference filters which were recently completed. The filter set consists of bandpass filters in the range between 348,5 nm and 910 nm and a longpass filter at 915 nm. Most of the filters have FWHM of 14.5 nm and a blocking between 250 and 1050 nm with optical density of OD5. Absorptive color glass substrates in combination with interference filters were used to minimize residual reflection in order to avoid ghost images. Inspite of containing absorptive elements, the filters show the maximum possible transmission. This was achieved by using magnetron sputtering for the filter coating process. The most important requirement for the continuous photometric survey is the tight tolerancing of the central wavelengths and FWHM of the filters. This insures each bandpass having a defined overlap with its neighbors. In addition, the blocking of the filters is better than OD5 in the range 250-1050 nm. A high image quality required a low transmitted wavefront error (substrates. We report on the spectral and interferometric results measured on the whole set of filters. λλ

Artificial intelligence applications at the ICPP

International Nuclear Information System (INIS)

Johnson, C.E.

1989-01-01

Westinghouse Idaho Nuclear Company (WINCO) initiated an aggressive program for artificial intelligence (AI) expert system implementations in 1985. The first expert system, Safety Analysis Methods Advisor (SAMA) was completed in 1986 to help operational safety analysts select analysis methodologies for safety analysis reports. The SAMA expert system was implemented as a rule-based system using a commercial expert system shell. The major benefit of the system is for training new safety analysts. The first successful implementation launched three other expert system projects: a process alarm filtering system, a process control advisor, and a mass spectrometer trouble-shooting advisor. This paper describes the current status of these projects

Application of a zero-latency whitening filter to compact binary coalescence gravitational-wave searches

Science.gov (United States)

Tsukada, Leo; Cannon, Kipp; Hanna, Chad; Keppel, Drew; Meacher, Duncan; Messick, Cody

2018-05-01

Joint electromagnetic and gravitational-wave (GW) observation is a major goal of both the GW astronomy and electromagnetic astronomy communities for the coming decade. One way to accomplish this goal is to direct follow-up of GW candidates. Prompt electromagnetic emission may fade quickly, therefore it is desirable to have GW detection happen as quickly as possible. A leading source of latency in GW detection is the whitening of the data. We examine the performance of a zero-latency whitening filter in a detection pipeline for compact binary coalescence (CBC) GW signals. We find that the filter reproduces signal-to-noise ratio (SNR) sufficiently consistent with the results of the original high-latency and phase-preserving filter for both noise and artificial GW signals (called "injections"). Additionally, we demonstrate that these two whitening filters show excellent agreement in χ2 value, a discriminator for GW signals.

Design of UWB Filter with WLAN Notch

Directory of Open Access Journals (Sweden)

Harish Kumar

2012-01-01

Full Text Available UWB technology- (operating in broad frequency range of 3.1–10.6 GHz based filter with WLAN notch has shown great achievement for high-speed wireless communications. To satisfy the UWB system requirements, a band pass filter with a broad pass band width, low insertion loss, and high stop-band suppression are needed. UWB filter with wireless local area network (WLAN notch at 5.6 GHz and 3 dB fractional bandwidth of 109.5% using a microstrip structure is presented. Initially a two-transmission-pole UWB band pass filter in the frequency range 3.1–10.6 GHz is achieved by designing a parallel-coupled microstrip line with defective ground plane structure using GML 1000 substrate with specifications: dielectric constant 3.2 and thickness 0.762 mm at centre frequency 6.85 GHz. In this structure a λ/4 open-circuited stub is introduced to achieve the notch at 5.6 GHz to avoid the interference with WLAN frequency which lies in the desired UWB band. The design structure was simulated on electromagnetic circuit simulation software and fabricated by microwave integrated circuit technique. The measured VNA results show the close agreement with simulated results.

Reflection color filters of the three primary colors with wide viewing angles using common-thickness silicon subwavelength gratings.

Science.gov (United States)

Kanamori, Yoshiaki; Ozaki, Toshikazu; Hane, Kazuhiro

2014-10-20

We fabricated reflection color filters of the three primary colors with wide viewing angles using silicon two-dimensional subwavelength gratings on the same quartz substrate. The grating periods were 400, 340, and 300 nm for red, green, and blue filters, respectively. All of the color filters had the same grating thickness of 100 nm, which enabled simple fabrication of a color filter array. Reflected colors from the red, green, and blue filters under s-polarized white-light irradiation appeared in the respective colors at incident angles from 0 to 50°. By rigorous coupled-wave analysis, the dimensions of each color filter were designed, and the calculated reflectivity was compared with the measured reflectivity.

The analysis and application of a new hybrid pollutants forecasting model using modified Kolmogorov-Zurbenko filter.

Science.gov (United States)

Li, Peizhi; Wang, Yong; Dong, Qingli

2017-04-01

Cities in China suffer from severe smog and haze, and a forecasting system with high accuracy is of great importance to foresee the concentrations of the airborne particles. Compared with chemical transport models, the growing artificial intelligence models can simulate nonlinearities and interactive relationships and getting more accurate results. In this paper, the Kolmogorov-Zurbenko (KZ) filter is modified and firstly applied to construct the model using an artificial intelligence method. The concentration of inhalable particles and fine particulate matter in Dalian are used to analyze the filtered components and test the forecasting accuracy. Besides, an extended experiment is made by implementing a comprehensive comparison and a stability test using data in three other cities in China. Results testify the excellent performance of the developed hybrid models, which can be utilized to better understand the temporal features of pollutants and to perform a better air pollution control and management. Copyright © 2017 Elsevier B.V. All rights reserved.

Soot accumulation in diesel particulate filters using ULSD and B20 biodiesel fuel blends

Energy Technology Data Exchange (ETDEWEB)

Charbonneau, P.; Wallace, J.S. [Toronto Univ., ON (Canada)

2009-07-01

Soot accumulation in a diesel particulate filter was investigated using a newly developed dissection method that loads and dissects diesel particulate filters (DPFs). In particular, this study examined the differences in soot accumulation between ultra-low sulphur diesel (ULSD) and a B20 biodiesel blend. DPFs loaded for exposure times of 1, 2, 5 and 10 hours. Scanning electron microscopy (SEM) was used to analyze the samples of the filter substrate. The differences in particulate size and number distribution between fuels were attributed to performance differences in DPFs. ULSD loaded filters experienced increased loading and a greater pressure drop across the filters. According to SEM images, the soot cake was a relatively shallow feature increasing in density to form discrete coarse agglomerates and cakes. It was concluded that this newly developed methodology has potential for future studies in DPF loading.

Engineering of metabolic pathways by artificial enzyme channels

Directory of Open Access Journals (Sweden)

Marlene ePröschel

2015-10-01

Full Text Available Application of industrial enzymes for production of valuable chemical compounds has greatly benefited from recent developments in Systems and Synthetic Biology. Both, in vivo and in vitro systems have been established, allowing conversion of simple into complex compounds. Metabolic engineering in living cells needs to be balanced which is achieved by controlling gene expression levels, translation, scaffolding, compartmentation and flux control. In vitro applications are often hampered by limited protein stability/half-life and insufficient rates of substrate conversion. To improve stability and catalytic activity, proteins are post-translationally modified and arranged in artificial metabolic channels. Within the review article we will first discuss the supramolecular organization of enzymes in living systems and secondly summarize current and future approaches to design artificial metabolic channels by additive manufacturing for the efficient production of desired products.

Spectral and Wavefront Error Performance of WFIRST/AFTA Prototype Filters

Science.gov (United States)

Quijada, Manuel; Seide, Laurie; Marx, Cathy; Pasquale, Bert; McMann, Joseph; Hagopian, John; Dominguez, Margaret; Gong, Qian; Morey, Peter

2016-01-01

The Cycle 5 design baseline for the Wide-Field Infrared Survey Telescope Astrophysics Focused Telescope Assets (WFIRSTAFTA) instrument includes a single wide-field channel (WFC) instrument for both imaging and slit-less spectroscopy. The only routinely moving part during scientific observations for this wide-field channel is the element wheel (EW) assembly. This filter-wheel assembly will have 8 positions that will be populated with 6 bandpass filters, a blank position, and a Grism that will consist of a three-element assembly to disperse the full field with an undeviated central wavelength for galaxy redshift surveys. All filter elements in the EW assembly will be made out of fused silica substrates (110 mm diameter) that will have the appropriate bandpass coatings according to the filter designations (Z087, Y106, J129, H158, F184, W149 and Grism). This paper presents and discusses the performance (including spectral transmission and reflectedtransmitted wavefront error measurements) of a subset of bandpass filter coating prototypes that are based on the WFC instrument filter compliment. The bandpass coating prototypes that are tested in this effort correspond to the Z087, W149, and Grism filter elements. These filter coatings have been procured from three different vendors to assess the most challenging aspects in terms of the in-band throughput, out of band rejection (including the cut-on and cutoff slopes), and the impact the wavefront error distortions of these filter coatings will have on the imaging performance of the de-field channel in the WFIRSTAFTA observatory.

Application Of Artificial Neural Networks In Modeling Of Manufactured Front Metallization Contact Resistance For Silicon Solar Cells

Directory of Open Access Journals (Sweden)

Musztyfaga-Staszuk M.

2015-09-01

Full Text Available This paper presents the application of artificial neural networks for prediction contact resistance of front metallization for silicon solar cells. The influence of the obtained front electrode features on electrical properties of solar cells was estimated. The front electrode of photovoltaic cells was deposited using screen printing (SP method and next to manufactured by two methods: convectional (1. co-fired in an infrared belt furnace and unconventional (2. Selective Laser Sintering. Resistance of front electrodes solar cells was investigated using Transmission Line Model (TLM. Artificial neural networks were obtained with the use of Statistica Neural Network by Statsoft. Created artificial neural networks makes possible the easy modelling of contact resistance of manufactured front metallization and allows the better selection of production parameters. The following technological recommendations for the screen printing connected with co-firing and selective laser sintering technology such as optimal paste composition, morphology of the silicon substrate, co-firing temperature and the power and scanning speed of the laser beam to manufacture the front electrode of silicon solar cells were experimentally selected in order to obtain uniformly melted structure well adhered to substrate, of a small front electrode substrate joint resistance value. The prediction possibility of contact resistance of manufactured front metallization is valuable for manufacturers and constructors. It allows preserving the customers’ quality requirements and bringing also measurable financial advantages.

Efecto de diversos sustratos artificiales en el crecimiento y supervivencia de estadios tempranos de la langosta azul (Cherax quadricarinatus) cultivados en un sistema de recirculación - Effect of different artificial substrates on growth and survival of early stages of the blue lobster (Cherax quadricarinatus) reared in a recirculating system

OpenAIRE

García-Ulloa Gómez, Manuel; Pinzón López, Liliana Araceli

2012-01-01

ResumenSe evaluó la influencia de diferentes sustratos artificiales (tubo, malla, tubo + malla y grupo control, sin sustrato) sobre el crecimiento y la supervivencia de crías tempranas de Cherax quadricarinatus, cultivadas en un sistema derecirculación durante cuatro semanas.AbstractThe effect of different artificial substrates (tube or straw, mesh, mesh and tube or straw, and control or no substrate) on growth and survival of offspring early Cherax quadricarinatus raised in a recirculating s...

Octopus-like suction cups: from natural to artificial solutions.

Science.gov (United States)

Tramacere, F; Follador, M; Pugno, N M; Mazzolai, B

2015-05-13

Octopus suckers are able to attach to all nonporous surfaces and generate a very strong attachment force. The well-known attachment features of this animal result from the softness of the sucker tissues and the surface morphology of the portion of the sucker that is in contact with objects or substrates. Unlike artificial suction cups, octopus suckers are characterized by a series of radial grooves that increase the area subjected to pressure reduction during attachment. In this study, we constructed artificial suction cups with different surface geometries and tested their attachment performances using a pull-off setup. First, smooth suction cups were obtained for casting; then, sucker surfaces were engraved with a laser cutter. As expected, for all the tested cases, the engraving treatment enhanced the attachment performance of the elastomeric suction cups compared with that of the smooth versions. Moreover, the results indicated that the surface geometry with the best attachment performance was the geometry most similar to octopus sucker morphology. The results obtained in this work can be utilized to design artificial suction cups with higher wet attachment performance.

Magnetoresistance at artificial interfaces in epitaxial ferromagnetic thin films

International Nuclear Information System (INIS)

Fontcuberta, J.; Bibes, M.; Martinez, B.; Trtik, V.; Ferrater, C.; Sanchez, F.; Varela, M.

2000-01-01

Epitaxial La 2/3 Sr 1/3 MnO 3 and SrRuO 3 thin films have been grown by laser ablation on single-crystalline SrTiO 3 substrates. Prior to manganite or ruthenate deposition tracks have been patterned on the SrTiO 3 substrate by using an appropriately focused laser beam. In the experiments here reported linear tracks have been formed. The magnetotransport properties of the films, particularly the magnetoresistance, along paths parallel and perpendicular to the track have been extensively investigated and compared to similar data recorded on films grown on bicrystalline STO substrates. Whereas in LSMO a significant low-field tunnel magnetoresistance develops across the artificial interface, in SRO this tunnel contribution is absent. However, a significant high-field magnetoresistance is observed for both metallic and ferromagnetic systems. The results are analysed and discussed within the framework of the current understanding of double exchange and itinerant ferromagnets. Magnetoresistance data for various configurations of the track array are presented

Artificial Consciousness or Artificial Intelligence

OpenAIRE

Spanache Florin

2017-01-01

Artificial intelligence is a tool designed by people for the gratification of their own creative ego, so we can not confuse conscience with intelligence and not even intelligence in its human representation with conscience. They are all different concepts and they have different uses. Philosophically, there are differences between autonomous people and automatic artificial intelligence. This is the difference between intelligence and artificial intelligence, autonomous versus a...

Ultrathin metal-semiconductor-metal resonator for angle invariant visible band transmission filters

International Nuclear Information System (INIS)

Lee, Kyu-Tae; Seo, Sungyong; Yong Lee, Jae; Jay Guo, L.

2014-01-01

We present transmission visible wavelength filters based on strong interference behaviors in an ultrathin semiconductor material between two metal layers. The proposed devices were fabricated on 2 cm × 2 cm glass substrate, and the transmission characteristics show good agreement with the design. Due to a significantly reduced light propagation phase change associated with the ultrathin semiconductor layer and the compensation in phase shift of light reflecting from the metal surface, the filters show an angle insensitive performance up to ±70°, thus, addressing one of the key challenges facing the previously reported photonic and plasmonic color filters. This principle, described in this paper, can have potential for diverse applications ranging from color display devices to the image sensors.

Development of a double-layered ceramic filter for aerosol filtration at high-temperatures: the filter collection efficiency.

Science.gov (United States)

de Freitas, Normanda L; Gonçalves, José A S; Innocentini, Murilo D M; Coury, José R

2006-08-25

The performance of double-layered ceramic filters for aerosol filtration at high temperatures was evaluated in this work. The filtering structure was composed of two layers: a thin granular membrane deposited on a reticulate ceramic support of high porosity. The goal was to minimize the high pressure drop inherent of granular structures, without decreasing their high collection efficiency for small particles. The reticulate support was developed using the technique of ceramic replication of polyurethane foam substrates of 45 and 75 pores per inch (ppi). The filtering membrane was prepared by depositing a thin layer of granular alumina-clay paste on one face of the support. Filters had their permeability and fractional collection efficiency analyzed for filtration of an airborne suspension of phosphatic rock in temperatures ranging from ambient to 700 degrees C. Results revealed that collection efficiency decreased with gas temperature and was enhanced with filtration time. Also, the support layer influenced the collection efficiency: the 75 ppi support was more effective than the 45 ppi. Particle collection efficiency dropped considerably for particles below 2 microm in diameter. The maximum collection occurred for particle diameters of approximately 3 microm, and decreased again for diameters between 4 and 8 microm. Such trend was successfully represented by the proposed correlation, which is based on the classical mechanisms acting on particle collection. Inertial impaction seems to be the predominant collection mechanism, with particle bouncing/re-entrainment acting as detachment mechanisms.

Top-down Approach for the Direct Synthesis, Patterning, and Operation of Artificial Micromuscles on Flexible Substrates.

Science.gov (United States)

Maziz, Ali; Plesse, Cédric; Soyer, Caroline; Cattan, Eric; Vidal, Frédéric

2016-01-27

Recent progress in the field of microsystems on flexible substrates raises the need for alternatives to the stiffness of classical actuation technologies. This paper reports a top-down process to microfabricate soft conducting polymer actuators on substrates on which they ultimately operate. The bending microactuators were fabricated by sequentially stacking layers using a layer polymerization by layer polymerization of conducting polymer electrodes and a solid polymer electrolyte. Standalone microbeams thinner than 10 μm were fabricated on SU-8 substrates associated with a bottom gold electrical contact. The operation of microactuators was demonstrated in air and at low voltage (±4 V).

Micromachined high-performance RF passives in CMOS substrate

International Nuclear Information System (INIS)

Li, Xinxin; Ni, Zao; Gu, Lei; Wu, Zhengzheng; Yang, Chen

2016-01-01

This review systematically addresses the micromachining technologies used for the fabrication of high-performance radio-frequency (RF) passives that can be integrated into low-cost complementary metal-oxide semiconductor (CMOS)-grade (i.e. low-resistivity) silicon wafers. With the development of various kinds of post-CMOS-compatible microelectromechanical systems (MEMS) processes, 3D structural inductors/transformers, variable capacitors, tunable resonators and band-pass/low-pass filters can be compatibly integrated into active integrated circuits to form monolithic RF system-on-chips. By using MEMS processes, including substrate modifying/suspending and LIGA-like metal electroplating, both the highly lossy substrate effect and the resistive loss can be largely eliminated and depressed, thereby meeting the high-performance requirements of telecommunication applications. (topical review)

Experimental quantum control landscapes: Inherent monotonicity and artificial structure

International Nuclear Information System (INIS)

Roslund, Jonathan; Rabitz, Herschel

2009-01-01

Unconstrained searches over quantum control landscapes are theoretically predicted to generally exhibit trap-free monotonic behavior. This paper makes an explicit experimental demonstration of this intrinsic monotonicity for two controlled quantum systems: frequency unfiltered and filtered second-harmonic generation (SHG). For unfiltered SHG, the landscape is randomly sampled and interpolation of the data is found to be devoid of landscape traps up to the level of data noise. In the case of narrow-band-filtered SHG, trajectories are taken on the landscape to reveal a lack of traps. Although the filtered SHG landscape is trap free, it exhibits a rich local structure. A perturbation analysis around the top of these landscapes provides a basis to understand their topology. Despite the inherent trap-free nature of the landscapes, practical constraints placed on the controls can lead to the appearance of artificial structure arising from the resultant forced sampling of the landscape. This circumstance and the likely lack of knowledge about the detailed local landscape structure in most quantum control applications suggests that the a priori identification of globally successful (un)constrained curvilinear control variables may be a challenging task.

Weather resistance of inkjet prints on plastic substrates

Directory of Open Access Journals (Sweden)

Rozália Szentgyörgyvölgyi

2015-06-01

Full Text Available The development of wide format inkjet printers made the technology available for large area commercials. Outdoor advertising uses a wide range of substrate including paperboard, vinyl, canvas, mesh; the material of the substrate itself has to endure the physical and chemical effects of local weather. Weather elements (humidity, wind, solar irradiation degrade printed products inevitably; plastic products have better resistance against them, than paper based substrates. Service life of the printed product for outdoor application is a key parameter from the customer’s point of view. There are two ways to estimate expected lifetime: on site outdoor testing or laboratory testing. In both cases weathering parameters can be monitored, however laboratory testing devices may produce the desired environmental effects and thus accelerate the aging process. Our research objective was to evaluate the effects of artificial weathering on prints produced by inkjet technology on plastic substrates. We used a large format CMYK inkjet printer (Mutoh Rockhopper II, with Epson DX 4 print heads to print our test chart on two similar substrates (PVC coated tarpaulins with grammages 400 g/m2 and 440 g/m2. Specimen were aged in an Atlas Suntest XLS+ material tester device for equal time intervals. We measured and calculated the gradual changes of the optical properties (optical density, tone value, colour shifts of the test prints.

Solar–terrestrial radiant-energy regimes and temperature anomalies of natural and artificial turfs

International Nuclear Information System (INIS)

Jim, C.Y.

2016-01-01

Highlights: • Solar and terrestrial radian energy regimes affect temperature response of sports turfs. • Adjacent natural and artificial turfs were monitored with replications on sunny days. • Artificial turf has meager albedo, low specific heat and moisture to augment warming. • Artificial turf surface and substrate reach 70 °C but cool down effectively at night. • Artificial turf may induce heat stress on athletes in hot summer afternoon. - Abstract: Artificial turf can develop unusually high surface temperature on hot sunny days. Solar and terrestrial radiant energy regimes as key determinants of thermal performance deserve detailed investigation. This study evaluated six components of the radiant-energy environment of a natural turf (NT) and a contiguous artificial turf (AT) sports fields in Hong Kong: direct solar, reflected solar, net solar, sky thermal, ground thermal, and net thermal. Temperature was monitored at five positions: air at 150 cm, 50 cm and 15 cm height, turf surface, and substrate. The experiment included four replications, namely two summer sunny days, and two duplicated instrument sets at each turf site. The two sites reacted very differently to the same intense daily sum of solar radiation input of 23.70 MW m −2 with 9 h of bright sunshine (>120 W m −2 ), and daily sum of sky thermal radiation input of 38.59 MW m −2 . The maximum direct solar radiation reached 976.1 W m −2 at 1245 h. NT albedo of 0.23 vis-à-vis AT of merely 0.073, and higher moisture content and specific heat of NT materials, presented critical differences. The hydrophobic and generally dry plastic (polyethylene) pile-fibers and black rubber-granule infill materials have low specific heat. Intense incoming shortwave and longwave radiation absorbed readily by AT materials raised turf surface temperature to 70.2 °C and substrate 69.3 °C, in comparison with <40 °C at NT. A cascading warming effect was triggered, beginning with low albedo, high net solar

Artificial dirt: microfluidic substrates for nematode neurobiology and behavior.

Science.gov (United States)

Lockery, S R; Lawton, K J; Doll, J C; Faumont, S; Coulthard, S M; Thiele, T R; Chronis, N; McCormick, K E; Goodman, M B; Pruitt, B L

2008-06-01

With a nervous system of only 302 neurons, the free-living nematode Caenorhabditis elegans is a powerful experimental organism for neurobiology. However, the laboratory substrate commonly used in C. elegans research, a planar agarose surface, fails to reflect the complexity of this organism's natural environment, complicates stimulus delivery, and is incompatible with high-resolution optophysiology experiments. Here we present a new class of microfluidic devices for C. elegans neurobiology and behavior: agarose-free, micron-scale chambers and channels that allow the animals to crawl as they would on agarose. One such device mimics a moist soil matrix and facilitates rapid delivery of fluid-borne stimuli. A second device consists of sinusoidal channels that can be used to regulate the waveform and trajectory of crawling worms. Both devices are thin and transparent, rendering them compatible with high-resolution microscope objectives for neuronal imaging and optical recording. Together, the new devices are likely to accelerate studies of the neuronal basis of behavior in C. elegans.

Deposition of a conductive near-infrared cutoff filter by radio-frequency magnetron sputtering

International Nuclear Information System (INIS)

Lee, Jang-Hoon; Lee, Seung-Hyu; Yoo, Kwang-Lim; Kim, Nam-Young; Hwangbo, Chang Kwon

2002-01-01

We have designed a conductive near-infrared (NIR) cutoff filter for display application, i.e., a modified low-emissivity filter based on the three periods of the basic design of [TiO2|Ti|Ag| TiO2] upon a glass substrate and investigated the optical, structural, chemical, and electrical properties of the conductive NIR cutoff filter prepared by a radio frequency magnetron sputtering system. The results show that the average transmittance is 61.1% in the visible, that the transmittance in the NIR is less than 6.6%, and that the sheet resistance and emissivity are 0.9 Ω/□ (where □ stands for a square film) and 0.012, respectively, suggesting that the conductive NIR cutoff filter can be employed as a shield against the hazard of electromagnetic waves as well as to cut off the NIR

Large eddy simulations of round free jets using explicit filtering with/without dynamic Smagorinsky model

International Nuclear Information System (INIS)

Bogey, Christophe; Bailly, Christophe

2006-01-01

Large eddy simulations (LES) of round free jets at Mach number M = 0.9 with Reynolds numbers over the range 2.5 x 10 3 ≤ Re D ≤ 4 x 10 5 are performed using explicit selective/high-order filtering with or without dynamic Smagorinsky model (DSM). Features of the flows and of the turbulent kinetic energy budgets in the turbulent jets are reported. The contributions of molecular viscosity, filtering and DSM to energy dissipation are also presented. Using filtering alone, the results are independent of the filtering strength, and the effects of the Reynolds number on jet development are successfully calculated. Using DSM, the effective jet Reynolds number is found to be artificially decreased by the eddy viscosity. The results are also not appreciably modified when subgrid-scale kinetic energy is used. Moreover, unlike filtering which does not significantly affect the larger computed scales, the eddy viscosity is shown to dissipate energy through all the turbulent scales, in the same way as molecular viscosity at lower Reynolds numbers

Artificial intelligence applied to process signal analysis

Science.gov (United States)

Corsberg, Dan

1988-01-01

Many space station processes are highly complex systems subject to sudden, major transients. In any complex process control system, a critical aspect of the human/machine interface is the analysis and display of process information. Human operators can be overwhelmed by large clusters of alarms that inhibit their ability to diagnose and respond to a disturbance. Using artificial intelligence techniques and a knowledge base approach to this problem, the power of the computer can be used to filter and analyze plant sensor data. This will provide operators with a better description of the process state. Once a process state is recognized, automatic action could be initiated and proper system response monitored.

Parametric adaptive filtering and data validation in the bar GW detector AURIGA

CERN Document Server

Ortolan, A; Cerdonio, M; Prodi, G A; Vedovato, G; Vitale, S

2002-01-01

We report on our experience gained in the signal processing of the resonant GW detector AURIGA. Signal amplitude and arrival time are estimated by means of a matched-adaptive Wiener filter. The detector noise, entering in the filter set-up, is modelled as a parametric ARMA process; to account for slow non-stationarity of the noise, the ARMA parameters are estimated on an hourly basis. A requirement of the set-up of an unbiased Wiener filter is the separation of time spans with 'almost Gaussian' noise from non-Gaussian and/or strongly non-stationary time spans. The separation algorithm consists basically of a variance estimate with the Chauvenet convergence method and a threshold on the Curtosis index. The subsequent validation of data is strictly connected with the separation procedure: in fact, by injecting a large number of artificial GW signals into the 'almost Gaussian' part of the AURIGA data stream, we have demonstrated that the effective probability distributions of the signal-to-noise ratio chi sup 2 ...

Investigation of New Microstrip Bandpass Filter Based on Patch Resonator with Geometrical Fractal Slot.

Directory of Open Access Journals (Sweden)

Yaqeen S Mezaal

Full Text Available A compact dual-mode microstrip bandpass filter using geometrical slot is presented in this paper. The adopted geometrical slot is based on first iteration of Cantor square fractal curve. This filter has the benefits of possessing narrower and sharper frequency responses as compared to microstrip filters that use single mode resonators and traditional dual-mode square patch resonators. The filter has been modeled and demonstrated by Microwave Office EM simulator designed at a resonant frequency of 2 GHz using a substrate of εr = 10.8 and thickness of h = 1.27 mm. The output simulated results of the proposed filter exhibit 22 dB return loss, 0.1678 dB insertion loss and 12 MHz bandwidth in the passband region. In addition to the narrow band gained, miniaturization properties as well as weakened spurious frequency responses and blocked second harmonic frequency in out of band regions have been acquired. Filter parameters including insertion loss, return loss, bandwidth, coupling coefficient and external quality factor have been compared with different values of perturbation dimension (d. Also, a full comparative study of this filter as compared with traditional square patch filter has been considered.

Measurement of alpha-aerosol activity concentration by a moving filter device. Numerical simulation of both filter activity load and continuous monitoring process by compensation of natural activity by means of ABPD and AERD; Bilanzierung der Alpha-Aktivitaetskonzentration der Raumluft mit einem Schrittbandfiltergeraet. Numerische Simulation des Verlaufs der Bestaubung und der kontinuierlichen Auswertung mit Kompensation der natuerlichen Aktivitaet durch ABPD und AERD

Energy Technology Data Exchange (ETDEWEB)

Kraut, W.; Schwarz, W. [Duale Hochschule Baden-Wuerttemberg (DHBW), Karlsruhe (Germany). Studiengang Sicherheitswesen; Kraut, B. [Berthold Technologies GmbH und Co.KG, Bad Wildbad (Germany)

2016-07-01

Moving filter aerosol monitors offer the advantage of better measurement conditions by reducing the load of dust and activity. But at the same time the dynamical follow up of increasing or decreasing activity air concentrations is getting more complex by superposition oft the filter movement, especially if there are both short lived natural and long lived artificial activity to be monitored. The paper shows by a pure numerical simulation of activity load and measurement of Radon-daughters and long lived artificial activity, that a stable determination of activity concentration is possible right from the beginning of sampling. This is accomplished by multivariate regression analysis to separate short lived Po-218 and long lived artificial - Activity. Po-214 activity is compensated by means of ABPD and AERD techniques. The Model allows for variable activity concentrations during sampling. Results are presented.

Effects of dynamic operating conditions on nitrification in biological rapid sand filters for drinking water treatment

DEFF Research Database (Denmark)

Lee, Carson Odell; Boe-Hansen, Rasmus; Musovic, Sanin

2014-01-01

Biological rapid sand filters are often used to remove ammonium from groundwater for drinking water supply. They often operate under dynamic substrate and hydraulic loading conditions, which can lead to increased levels of ammonium and nitrite in the effluent. To determine the maximum nitrification...... operating conditions. The ammonium removal rate of the filter was determined by the ammonium loading rate, but was independent of both the flow and influent ammonium concentration individually. Ammonia-oxidizing bacteria and archaea were almost equally abundant in the filter. Both ammonium removal...... rates and safe operating windows of rapid sand filters, a pilot scale rapid sand filter was used to test short-term increased ammonium loads, set by varying either influent ammonium concentrations or hydraulic loading rates. Ammonium and iron (flock) removal were consistent between the pilot...

Drainage filter technologies to mitigate site-specific phosphorus losses

DEFF Research Database (Denmark)

Kjærgaard, Charlotte; Heckrath, Goswin Johann; Iversen, Bo Vangsø

2014-01-01

-specific nutrient losses in drainage. The “SUPREME-TECH” project (2010-2015), funded by the Danish Strategic Research Council, aims at providing the scientific basis for developing cost-effective drainage filter technologies to retain P in agricultural drainage waters. The project studies different approaches...... high risks areas of P loss and applying site-specific measures therefore seems a more cost-efficient approach. The Danish Commission for Nature and Agriculture has now called for a shift of paradigm towards targeted mitigation and development of new, cost-efficient technologies to mitigate site......-scale surface-flow constructed wetland. In the former, various natural and industrial P filter substrates have been tested for their ability to reduce inlet P concentrations to below environmental threshold values (

Natural - synthetic - artificial!

DEFF Research Database (Denmark)

Nielsen, Peter E

2010-01-01

The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life.......The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life....

A new fold-cross metal mesh filter for suppressing side lobe leakage in terahertz region

Science.gov (United States)

Lu, Changgui; Qi, Zhengqing; Guo, Wengao; Cui, Yiping

2018-04-01

In this paper we propose a new type of fold-cross metal mesh band pass filter, which keeps diffraction side lobe far away from the main transmission peak and shows much better side lobe suppression. Both experimental and theoretical studies are made to analyze the mechanism of side lobe. Compared to the traditional cross filter, the fold-cross filter has a much lower side lobe with almost the same central frequency, bandwidth and highest transmission about 98%. Using the photolithography and electroplating techniques, we experimentally extend the distance between the main peak and diffraction side lobe to larger than 1 THz for the fold-cross filter, which is two times larger than the cross filter while maintaining the main peak transmissions of 89% at 1.25 THz for the two structures. This type of single layer substrate-free fold-cross metal structure shows better design flexibility and structure reliability with the introduction of fold arms for metal mesh band pass filters.

Investigation the effects of metallic substrate surfaces due to ion-plasma treatment

International Nuclear Information System (INIS)

Shulaev, V.M.; Taran, V.S.; Timoshenko, A.I.; Gasilin, V.V.

2011-01-01

It has been found correlation between modification effects and duration of ion-plasma cleaning the substrate surface with titanium ions. Experiments were carried out using serial vacuum-arc equipment ''Bulat-6'' at the stationary mode in non-filtered titanium plasma, which contained considerable quantity of evaporated material droplets. The polished cylinder substrates (diameter and height 9,14,20 mm) have been treated. The substrates were manufactured of stainless steel 12X18H10T and non-oxygen copper M00b. The substrates surface roughness after ion-plasma treatment has been investigated with electron microscope JEOL JSM-840 and optic interference non-contact profilograph- profilometer ''Micron-alpha''. According obtained results the surface of copper and stainless steel substrates has been treated to intensive modification, i.e. substrate surface after treatment significantly differs from initial one. During final ion-plasma treatment a number of effects occur: purification from surface oxides is accompanied with metallic surface ''contamination'' by the cathode material macrodroplets, surface micromelting accompanied by roughness increase, the surface layer annealing with noticeable decrease of hardness.

Thin film polarizer and color filter based on photo-polymerizable nematic liquid crystal

Science.gov (United States)

Mohammadimasoudi, Mohammad; Neyts, Kristiaan; Beeckman, Jeroen

2015-03-01

We present a method to fabricate a thin film color filter based on a mixture of photo-polymerizable liquid crystal and chiral dopant. A chiral nematic liquid crystal layer reflects light for a certain wavelength interval Δλ (= Δn.P) with the period and Δn the birefringence of the liquid crystal. The reflection band is determined by the chiral dopant concentration. The bandwidth is limited to 80nm and the reflectance is at most 50% for unpolarized incident light. The thin color filter is interesting for innovative applications like polarizer-free reflective displays, polarization-independent devices, stealth technologies, or smart switchable reflective windows to control solar light and heat. The reflected light has strong color saturation without absorption because of the sharp band edges. A thin film polarizer is developed by using a mixture of photo-polymerizable liquid crystal and color-neutral dye. The fabricated thin film absorbs light that is polarized parallel to the c axis of the LC. The obtained polarization ratio is 80% for a film of only 12 μm. The thin film polarizer and the color filter feature excellent film characteristics without domains and can be detached from the substrate which is useful for e.g. flexible substrates.

Sensory Pollution from Bag Filters, Carbon Filters and Combinations

DEFF Research Database (Denmark)

Bekö, Gabriel; Clausen, Geo; Weschler, Charles J.

2008-01-01

by an upstream pre-filter (changed monthly), an EU7 filter protected by an upstream activated carbon (AC) filter, and EU7 filters with an AC filter either downstream or both upstream and downstream. In addition, two types of stand-alone combination filters were evaluated: a bag-type fiberglass filter...... that contained AC and a synthetic fiber cartridge filter that contained AC. Air that had passed through used filters was most acceptable for those sets in which an AC filter was used downstream of the particle filter. Comparable air quality was achieved with the stand-alone bag filter that contained AC...

Epitaxial growth of AlN on single crystal Mo substrates

International Nuclear Information System (INIS)

Okamoto, Koichiro; Inoue, Shigeru; Nakano, Takayuki; Kim, Tae-Won; Oshima, Masaharu; Fujioka, Hiroshi

2008-01-01

We have grown AlN films on single-crystalline Mo(110), (100), and (111) substrates using a low temperature pulsed laser deposition (PLD) growth technique and investigated their structural properties. Although c-axis oriented AlN films grow on Mo(100), the films contain 30 o rotated domains due to the difference in the rotational symmetry between AlN(0001) and Mo(100). AlN films with only poor crystalline quality grow on Mo(111) substrates, probably due to the poor surface morphology and high reactivity of the substrates. On the other hand, single crystal AlN films grow epitaxially on Mo(110) substrates with an in-plane relationship of AlN[11-20] // Mo[001]. Reflection high-energy electron diffraction or electron backscattered diffraction analysis has revealed that neither in-plane 30 deg. rotated domains nor cubic phase domains exist in the AlN films. X-ray reflectivity measurements have revealed that the heterointerface between AlN and Mo prepared by PLD at 450 deg. C is quite abrupt. These results indicate that PLD epitaxial growth of AlN on single crystal Mo substrates is quite promising for the fabrication of future high frequency filter devices

Epitaxial growth of AlN on single crystal Mo substrates

Energy Technology Data Exchange (ETDEWEB)

Okamoto, Koichiro; Inoue, Shigeru [Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505 (Japan); Nakano, Takayuki; Kim, Tae-Won [Kanagawa Academy of Science and Technology (KAST) KSP east 301, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa, 213-0012 (Japan); Oshima, Masaharu [Department of Applied Chemistry, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656 (Japan); Fujioka, Hiroshi [Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8505 (Japan); Kanagawa Academy of Science and Technology (KAST) KSP east 301, 3-2-1 Sakado, Takatsu-ku, Kawasaki, Kanagawa, 213-0012 (Japan)], E-mail: hfujioka@iis.u-tokyo.ac.jp

2008-06-02

We have grown AlN films on single-crystalline Mo(110), (100), and (111) substrates using a low temperature pulsed laser deposition (PLD) growth technique and investigated their structural properties. Although c-axis oriented AlN films grow on Mo(100), the films contain 30{sup o} rotated domains due to the difference in the rotational symmetry between AlN(0001) and Mo(100). AlN films with only poor crystalline quality grow on Mo(111) substrates, probably due to the poor surface morphology and high reactivity of the substrates. On the other hand, single crystal AlN films grow epitaxially on Mo(110) substrates with an in-plane relationship of AlN[11-20] // Mo[001]. Reflection high-energy electron diffraction or electron backscattered diffraction analysis has revealed that neither in-plane 30 deg. rotated domains nor cubic phase domains exist in the AlN films. X-ray reflectivity measurements have revealed that the heterointerface between AlN and Mo prepared by PLD at 450 deg. C is quite abrupt. These results indicate that PLD epitaxial growth of AlN on single crystal Mo substrates is quite promising for the fabrication of future high frequency filter devices.

Characterization of glass filter micromodels used for polymer EOR flooding experiments

Energy Technology Data Exchange (ETDEWEB)

Foedisch, H.; Wegner, J.; Hincapie-Reina, R.; Ganzer, L. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). ITE

2013-08-01

This work is conducted as part of the research project DGMK 746 - ''Experimental and Numerical Analysis of Polymer Flooding Processes Using Micromodels - From Pore Scale to Continuum Scale''. The industry standard to assess polymer flood performance is through flooding experiments with cores or plugs. A complement to flooding experiments in cores is represented by micromodels such as glass filters, which resemble real porous media through their porous structures. In this way, an almost unlimited number of equivalent samples can be produced. Moreover, compared to cores the micromodels enable visual access to the flooding process enabling a detailed process description. The sintered glass filters used in this work represent one way to make displacement processes inside artificial structures visible. However, challenges exist to transfer the results obtained from models composed of glass to real plugs or rock sections. Therefore, this study focuses on the comparison of glass filter micromodels and real rock samples composed of Bentheimer sandstone. We determine water permeability and oil-water relative permeability endpoints with flooding experiments, compare capillary pressure functions of the glass models obtained from mercury porosimetry analysis with results from Bentheimer sandstone, and characterize the glass filter with respect of connate water saturation using NMR-spectroscopy and porosity obtained from pycnometer measurements. (orig.)

Corrosion of gold alloys and titanium in artificial saliva

International Nuclear Information System (INIS)

Brune, D.; Evje, D.

1982-01-01

Two types of gold alloys and one type of pure titanium have been submitted to corrosion in artificial saliva for periods of up to about 2 months. The release of copper, gold and silver from the gold alloys as well as titanium from the titanium matrix was measured with nuclear tracer technique. The physical/chemical state of the corrosion products of gold alloys referring to the ionic state or presence in particulate form has been examined retaining the particulate matter on a glass filter. Copper was observed to be mainly present in the ionic state. Considerable amounts of gold were observed to be retained on the glass filter explained by the presence of gold in particulate form or as a compentent of a dispersed collloidal phase. The estimation of the release of titanium was registered by the tracer nuclide 46 Sc assuming particulate matter to be deteriorated from the titanium surface. (author)

Face Recognition Using Local Quantized Patterns and Gabor Filters

Science.gov (United States)

Khryashchev, V.; Priorov, A.; Stepanova, O.; Nikitin, A.

2015-05-01

The problem of face recognition in a natural or artificial environment has received a great deal of researchers' attention over the last few years. A lot of methods for accurate face recognition have been proposed. Nevertheless, these methods often fail to accurately recognize the person in difficult scenarios, e.g. low resolution, low contrast, pose variations, etc. We therefore propose an approach for accurate and robust face recognition by using local quantized patterns and Gabor filters. The estimation of the eye centers is used as a preprocessing stage. The evaluation of our algorithm on different samples from a standardized FERET database shows that our method is invariant to the general variations of lighting, expression, occlusion and aging. The proposed approach allows about 20% correct recognition accuracy increase compared with the known face recognition algorithms from the OpenCV library. The additional use of Gabor filters can significantly improve the robustness to changes in lighting conditions.

Metal-doped diamond-like carbon films synthesized by filter-arc deposition

International Nuclear Information System (INIS)

Weng, K.-W.; Chen, Y.-C.; Lin, T.-N.; Wang, D.-Y.

2006-01-01

Diamond-like carbon (DLC) thin films are extensively utilized in the semiconductor, electric and cutting machine industries owing to their high hardness, high elastic modulus, low friction coefficients and high chemical stability. DLC films are prepared by ion beam-assisted deposition (BAD), sputter deposition, plasma-enhanced chemical vapor deposition (PECVD), cathodic arc evaporation (CAE), and filter arc deposition (FAD). The major drawbacks of these methods are the degraded hardness associated with the low sp 3 /sp 2 bonding ratio, the rough surface and poor adhesion caused by the presence of particles. In this study, a self-developed filter arc deposition (FAD) system was employed to prepare metal-containing DLC films with a low particle density. The relationships between the DLC film properties, such as film structure, surface morphology and mechanical behavior, with variation of substrate bias and target current, are examined. Experimental results demonstrate that FAD-DLC films have a lower ratio, suggesting that FAD-DLC films have a greater sp 3 bonding than the CAE-DLC films. FAD-DLC films also exhibit a low friction coefficient of 0.14 and half of the number of surface particles as in the CAE-DLC films. Introducing a CrN interfacial layer between the substrate and the DLC films enables the magnetic field strength of the filter to be controlled to improve the adhesion and effectively eliminate the contaminating particles. Accordingly, the FAD system improves the tribological properties of the DLC films

Modelling of word usage frequency dynamics using artificial neural network

International Nuclear Information System (INIS)

Maslennikova, Yu S; Bochkarev, V V; Voloskov, D S

2014-01-01

In this paper the method for modelling of word usage frequency time series is proposed. An artificial feedforward neural network was used to predict word usage frequencies. The neural network was trained using the maximum likelihood criterion. The Google Books Ngram corpus was used for the analysis. This database provides a large amount of data on frequency of specific word forms for 7 languages. Statistical modelling of word usage frequency time series allows finding optimal fitting and filtering algorithm for subsequent lexicographic analysis and verification of frequency trend models

Artificial intelligence

CERN Document Server

Hunt, Earl B

1975-01-01

Artificial Intelligence provides information pertinent to the fundamental aspects of artificial intelligence. This book presents the basic mathematical and computational approaches to problems in the artificial intelligence field.Organized into four parts encompassing 16 chapters, this book begins with an overview of the various fields of artificial intelligence. This text then attempts to connect artificial intelligence problems to some of the notions of computability and abstract computing devices. Other chapters consider the general notion of computability, with focus on the interaction bet

Alternating current line-filter based on electrochemical capacitor utilizing template-patterned graphene.

Science.gov (United States)

Wu, Zhenkun; Li, Liyi; Lin, Ziyin; Song, Bo; Li, Zhuo; Moon, Kyoung-Sik; Wong, Ching-Ping; Bai, Shu-Lin

2015-06-17

Aluminum electrolytic capacitors (AECs) are widely used for alternating current (ac) line-filtering. However, their bulky size is becoming more and more incompatible with the rapid development of portable electronics. Here we report a scalable process to fabricate miniaturized graphene-based ac line-filters on flexible substrates at room temperature. In this work, graphene oxide (GO) is reduced by patterned metal interdigits at room temperature and used directly as the electrode material. The as-fabricated device shows a phase angle of -75.4° at 120 Hz with a specific capacitance of 316 µF/cm(2) and a RC time constant of 0.35 ms. In addition, it retains 97.2% of the initial capacitance after 10000 charge/discharge cycles. These outstanding performance characteristics of our device demonstrate its promising to replace the conventional AECs for ac line filtering.

Characterization of the cation-binding capacity of a potassium-adsorption filter used in red blood cell transfusion.

Science.gov (United States)

Suzuki, Takao; Muto, Shigeaki; Miyata, Yukio; Maeda, Takao; Odate, Takayuki; Shimanaka, Kimio; Kusano, Eiji

2015-06-01

A K(+) -adsorption filter was developed to exchange K(+) in the supernatant of stored irradiated red blood cells with Na(+) . To date, however, the filter's adsorption capacity for K(+) has not been fully evaluated. Therefore, we characterized the cation-binding capacity of this filter. Artificial solutions containing various cations were continuously passed through the filter in 30 mL of sodium polystyrene sulfonate at 10 mL/min using an infusion pump at room temperature. The cation concentrations were measured before and during filtration. When a single solution containing K(+) , Li(+) , H(+) , Mg(2+) , Ca(2+) , or Al(3+) was continuously passed through the filter, the filter adsorbed K(+) and the other cations in exchange for Na(+) in direct proportion to the valence number. The order of affinity for cation adsorption to the filter was Ca(2+) >Mg(2+) >K(+) >H(+) >Li(+) . In K(+) -saturated conditions, the filter also adsorbed Na(+) . After complete adsorption of these cations on the filter, their concentration in the effluent increased in a sigmoidal manner over time. Cations that were bound to the filter were released if a second cation was passed through the filter, despite the different affinities of the two cations. The ability of the filter to bind cations, especially K(+) , should be helpful when it is used for red blood cell transfusion at the bedside. The filter may also be useful to gain a better understanding of the pharmacological properties of sodium polystyrene sulfonate. © 2015 The Authors. Therapeutic Apheresis and Dialysis © 2015 International Society for Apheresis.

Filter arrays

Science.gov (United States)

Page, Ralph H.; Doty, Patrick F.

2017-08-01

The various technologies presented herein relate to a tiled filter array that can be used in connection with performance of spatial sampling of optical signals. The filter array comprises filter tiles, wherein a first plurality of filter tiles are formed from a first material, the first material being configured such that only photons having wavelengths in a first wavelength band pass therethrough. A second plurality of filter tiles is formed from a second material, the second material being configured such that only photons having wavelengths in a second wavelength band pass therethrough. The first plurality of filter tiles and the second plurality of filter tiles can be interspersed to form the filter array comprising an alternating arrangement of first filter tiles and second filter tiles.

Spectral and Wavefront Error Performance of WFIRST-AFTA Bandpass Filter Coating Prototypes

Science.gov (United States)

Quijada, Manuel A.; Seide, Laurie; Pasquale, Bert A.; McMann, Joseph C.; Hagopian, John G.; Dominguez, Margaret Z.; Gong, Quian; Marx, Catherine T.

2016-01-01

The Cycle 5 design baseline for the Wide-Field Infrared Survey Telescope Astrophysics Focused Telescope Assets (WFIRST/AFTA) instrument includes a single wide-field channel (WFC) instrument for both imaging and slit-less spectroscopy. The only routinely moving part during scientific observations for this wide-field channel is the element wheel (EW) assembly. This filter-wheel assembly will have 8 positions that will be populated with 6 bandpass filters, a blank position, and a Grism that will consist of a three-element assembly to disperse the full field with an undeviated central wavelength for galaxy redshift surveys. All filter elements in the EW assembly will be made out of fused silica substrates (110 mm diameter) that will have the appropriate bandpass coatings according to the filter designations (Z087, Y106, J129, H158, F184, W149 and Grism). This paper presents and discusses the performance (including spectral transmission and reflected/transmitted wavefront error measurements) of a subset of bandpass filter coating prototypes that are based on the WFC instrument filter compliment. The bandpass coating prototypes that are tested in this effort correspond to the Z087, W149, and Grism filter elements. These filter coatings have been procured from three different vendors to assess the most challenging aspects in terms of the in-band throughput, out of band rejection (including the cut-on and cutoff slopes), and the impact the wavefront error distortions of these filter coatings will have on the imaging performance of the wide-field channel in the WFIRST/AFTA observatory.

Nitrogen doping for adhesion improvement of DLC film deposited on Si substrate by Filtered Cathodic Vacuum Arc (FCVA) technique

Energy Technology Data Exchange (ETDEWEB)

Bootkul, D., E-mail: mo_duangkhae@hotmail.com [Department of General Science, Faculty of Science, Srinakharinwirot University, Bangkok 10110 (Thailand); Supsermpol, B.; Saenphinit, N. [Western Digital Company, Ayutthaya 13160 (Thailand); Aramwit, C. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50202 (Thailand); Intarasiri, S., E-mail: saweat@gmail.com [Science and Technology Research Institute, Chiang Mai University, Chiang Mai 50202 (Thailand)

2014-08-15

Diamond-like carbon (DLC) films have been used in many applications due to their attractive combination of properties including chemical inertness, corrosion protection, biocompatibility, high hardness, and low wear rates. However, they still have some limitations such as high internal stresses and low toughness which lead to poor adhesion of films. Synthesis of nitrogen-doped DLC (N-DLC) offers the possibility of overcoming these limitations. In this study, DLC films, namely tetrahedral amorphous carbon (ta-C) and nitrogen doped tetrahedral amorphous carbon (ta-C:N) were deposited on single crystalline Si wafer substrates using the Filtered Cathodic Vacuum Arc (FCVA) technique. Film characterizations were carried out by Raman spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM), triboindenter tester and nano-scratch tester. Measurement results showed that intentionally doping with nitrogen reduced the carbon sp{sup 3} content and increased the surface roughness in comparison with that of pure ta-C films. The hardness measurement confirmed the Raman and AFM analyses that adding nitrogen in ta-C films decreased the hardness, especially with high nitrogen content. However, the nano-scratch test revealed the increasing of the critical load with nitrogen. This work, then, extended its scope to investigate the properties of double-layer ta-C films which were composed of ta-C:N interlayer of various thickness around 10–30 nm and ta-C top-layer with thickness of around 80 nm. Microstructure characterization demonstrated that a ta-C:N interlayer gradually decreased the sp{sup 3} fraction in the films and increased film roughness whenever the ta-C:N interlayer thickness increased. In this structure, the tribological property in terms of adhesion to the Si substrate was significantly improved by about 20–90%, but the mechanical property in terms of hardness was gradually degraded by about 2–10%, compared to pure ta-C film, when the ta

DEVELOPMENT OF AN ADHESIVE CANDLE FILTER SAFEGUARD DEVICE; F

International Nuclear Information System (INIS)

John P. Hurley; Ann K. Henderson; Jan W. Nowok; Michael L. Swanson

2002-01-01

device at high temperatures in a dusty gas stream is difficult because of problems with materials corrosion, dust leakage, and detection of filter failure. Therefore, the Energy and Environmental Research Center is using its knowledge of the factors that make filter dust sticky at gas filtration temperatures to make a simple and inexpensive SGD that employs an adhesive yet thermodynamically stable coating on a highly porous ceramic substrate. The SGDs are placed on top of individual candle filters at the filtered gas exit. Upon failure of the filter, the dirty gas flows through the SGD where the adhesive surface rapidly and permanently traps dust particles, causing the device to plug and prevent the dust from reaching the turbine

Generation of an artificial skin construct containing a non-degradable fiber mesh: a potential transcutaneous interface

Energy Technology Data Exchange (ETDEWEB)

Cahn, Frederick [Biomedical Strategies Inc., San Diego, CA (United States); Kyriakides, Themis R [Vascular Biology and Therapeutics, Yale University, New Haven, CT 06536-9812 (United States)], E-mail: themis.kyriakides@yale.edu

2008-09-01

Generation of a stable interface between soft tissues and biomaterials could improve the function of transcutaneous prostheses, primarily by minimizing chronic infections. We hypothesized that inclusion of non-biodegradable biomaterials in an artificial skin substrate would improve integration of the neodermis. In the present study, we compared the biocompatibility of an experimental substrate, consisting of collagen and glycosylaminoglycans, with commercially available artificial skin of similar composition. By utilizing a mouse excisional wound model, we found that the source of collagen (bovine tendon versus hide), extent of injury and wound contraction were critical determinants of inflammation and neodermis formation. Reducing the extent of injury to underlying muscle reduced inflammation and improved remodeling; the improved conditions allowed the detection of a pro-inflammatory effect of hide-derived collagen. To eliminate the complication of wound contraction, subsequent grafts were performed in guinea pigs and showed that inclusion of carbon fibers or non-degradable sutures resulted in increased foreign body response (FBR) and altered remodeling. On the other hand, inclusion of a polyester multi-stranded mesh induced a mild FBR and allowed normal neodermis formation. Taken together, our observations suggest that non-degradable biomaterials can be embedded in an artificial skin construct without compromising its ability to induce neodermis formation.

Artificial Consciousness or Artificial Intelligence

Directory of Open Access Journals (Sweden)

Spanache Florin

2017-05-01

Full Text Available Artificial intelligence is a tool designed by people for the gratification of their own creative ego, so we can not confuse conscience with intelligence and not even intelligence in its human representation with conscience. They are all different concepts and they have different uses. Philosophically, there are differences between autonomous people and automatic artificial intelligence. This is the difference between intelligence and artificial intelligence, autonomous versus automatic. But conscience is above these differences because it is neither conditioned by the self-preservation of autonomy, because a conscience is something that you use to help your neighbor, nor automatic, because one’s conscience is tested by situations which are not similar or subject to routine. So, artificial intelligence is only in science-fiction literature similar to an autonomous conscience-endowed being. In real life, religion with its notions of redemption, sin, expiation, confession and communion will not have any meaning for a machine which cannot make a mistake on its own.

Wetting morphologies and their transitions in grooved substrates

Energy Technology Data Exchange (ETDEWEB)

Seemann, Ralf; Bommer, Stefan; Herrmann, Carsten; Michler, Dominik [Experimental Physics, Saarland University, D-66123 Saarbruecken (Germany); Brinkmann, Martin; Herminghaus, Stephan; Khare, Krishnacharya; Kostourou, Konstantina; Gurevich, Evgeny [Max Planck Institute for Dynamics and Self-Organization, D-37073 Goettingen (Germany); Law, Bruce M; McBride, Sean, E-mail: r.seemann@physik.uni-saarland.de [Department of Physics, Kansas State University, Manhattan, KS 66506 (United States)

2011-05-11

When exposed to a partially wetting liquid, many natural and artificial surfaces equipped with complex topographies display a rich variety of liquid interfacial morphologies. In the present article, we focus on a few simple paradigmatic surface topographies and elaborate on the statics and dynamics of the resulting wetting morphologies. It is demonstrated that the spectrum of wetting morphologies increases with increasing complexity of the groove structure. On elastically deformable substrates, additional structures in the liquid morphologies can be observed, which are caused by deformations of the groove geometry in the presence of capillary forces. The emergence of certain liquid morphologies in grooves can be actively controlled by changes in wettability and geometry. For electrically conducting solid substrates, the apparent contact angle can be varied by electrowetting. This allows, depending on groove geometry, a reversible or irreversible transport of liquid along surface grooves. In the case of irreversible liquid transport in triangular grooves, the dynamics of the emerging instability is sensitive to the apparent hydrodynamic slip at the substrate. On elastic substrates, the geometry can be varied in a straightforward manner by stretching or relaxing the sample. The imbibition velocity in deformable grooves is significantly reduced compared to solid grooves, which is a result of the microscopic deformation of the elastic groove material close to the three phase contact line.

Parametric adaptive filtering and data validation in the bar GW detector AURIGA

Science.gov (United States)

Ortolan, A.; Baggio, L.; Cerdonio, M.; Prodi, G. A.; Vedovato, G.; Vitale, S.

2002-04-01

We report on our experience gained in the signal processing of the resonant GW detector AURIGA. Signal amplitude and arrival time are estimated by means of a matched-adaptive Wiener filter. The detector noise, entering in the filter set-up, is modelled as a parametric ARMA process; to account for slow non-stationarity of the noise, the ARMA parameters are estimated on an hourly basis. A requirement of the set-up of an unbiased Wiener filter is the separation of time spans with 'almost Gaussian' noise from non-Gaussian and/or strongly non-stationary time spans. The separation algorithm consists basically of a variance estimate with the Chauvenet convergence method and a threshold on the Curtosis index. The subsequent validation of data is strictly connected with the separation procedure: in fact, by injecting a large number of artificial GW signals into the 'almost Gaussian' part of the AURIGA data stream, we have demonstrated that the effective probability distributions of the signal-to-noise ratio χ2 and the time of arrival are those that are expected.

Parametric adaptive filtering and data validation in the bar GW detector AURIGA

International Nuclear Information System (INIS)

Ortolan, A; Baggio, L; Cerdonio, M; Prodi, G A; Vedovato, G; Vitale, S

2002-01-01

We report on our experience gained in the signal processing of the resonant GW detector AURIGA. Signal amplitude and arrival time are estimated by means of a matched-adaptive Wiener filter. The detector noise, entering in the filter set-up, is modelled as a parametric ARMA process; to account for slow non-stationarity of the noise, the ARMA parameters are estimated on an hourly basis. A requirement of the set-up of an unbiased Wiener filter is the separation of time spans with 'almost Gaussian' noise from non-Gaussian and/or strongly non-stationary time spans. The separation algorithm consists basically of a variance estimate with the Chauvenet convergence method and a threshold on the Curtosis index. The subsequent validation of data is strictly connected with the separation procedure: in fact, by injecting a large number of artificial GW signals into the 'almost Gaussian' part of the AURIGA data stream, we have demonstrated that the effective probability distributions of the signal-to-noise ratio χ 2 and the time of arrival are those that are expected

Parametric adaptive filtering and data validation in the bar GW detector AURIGA

Energy Technology Data Exchange (ETDEWEB)

Ortolan, A [INFN - Laboratori Nazionali di Legnaro, Via Romea, 4 I-35020 Legnaro, Padova (Italy); Baggio, L [Department of Physics, University of Trento and INFN Gruppo Collegato di Trento, I-38050 Povo, Trento (Italy); Cerdonio, M [Department of Physics, University of Padova and INFN Sezione di Padova, Via Marzolo 8, I-35131 Padova (Italy); Prodi, G A [Department of Physics, University of Trento and INFN Gruppo Collegato di Trento, I-38050 Povo, Trento (Italy); Vedovato, G [INFN - Laboratori Nazionali di Legnaro, Via Romea, 4 I-35020 Legnaro, Padova (Italy); Vitale, S [Department of Physics, University of Trento and INFN Gruppo Collegato di Trento, I-38050 Povo, Trento (Italy)

2002-04-07

We report on our experience gained in the signal processing of the resonant GW detector AURIGA. Signal amplitude and arrival time are estimated by means of a matched-adaptive Wiener filter. The detector noise, entering in the filter set-up, is modelled as a parametric ARMA process; to account for slow non-stationarity of the noise, the ARMA parameters are estimated on an hourly basis. A requirement of the set-up of an unbiased Wiener filter is the separation of time spans with 'almost Gaussian' noise from non-Gaussian and/or strongly non-stationary time spans. The separation algorithm consists basically of a variance estimate with the Chauvenet convergence method and a threshold on the Curtosis index. The subsequent validation of data is strictly connected with the separation procedure: in fact, by injecting a large number of artificial GW signals into the 'almost Gaussian' part of the AURIGA data stream, we have demonstrated that the effective probability distributions of the signal-to-noise ratio {chi}{sup 2} and the time of arrival are those that are expected.

Endangered New Caledonian endemic mushroom coral Cantharellus noumeae in turbid, metal-rich, natural and artificial environments.

Science.gov (United States)

Gilbert, Antoine; Heintz, Tom; Hoeksema, Bert W; Benzoni, Francesca; Fernandez, Jean Michel; Fauvelot, Cécile; Andréfouët, Serge

2015-11-15

Since its description in 1984, little attention has been paid to the New Caledonian endemic mushroom coral Cantharellus noumeae (Fungiidae), an IUCN Red-listed, endangered coral species. Our study presents the first ever quantitative assessment conducted on C. noumeae populations for two contrasting sites in the same turbid bay. Sites differed by their substrates of artificial or natural origins. Metal concentrations of superficial sediment were measured. C. noumeae was found in high densities in metal-rich and turbid environments at both locations, reaching up to 288 individuals per 50m(2). It was 3.5 times more abundant on natural rock than on artificial substrates. Recruitment was also higher proportionally on rock (47% vs 7-14%). The composition of the associated coral communities included 30-37 species occurring in low densities. Our findings clarify the environmental niche of this species and its colonization potential, in order to eventually better characterize its conservation status. Copyright © 2015 Elsevier Ltd. All rights reserved.

Preliminary results for filtering-ecosystems in Val Trebbia (PC - Italy); Primi risultati per gli ecosistemi-filtro della Val Trebbia (PC)

Energy Technology Data Exchange (ETDEWEB)

Malcevschi, Sergio [Pavia, Univ. (Italy). Dipt. di Biologia Animale; Bisogni, G Luca [N.Q.A. s.r.l., Pavia (Italy); Bernini, Fabrizio [Amministrazione Provinciale di Piacenza, Piacenza (Italy)

1997-09-01

Some artificial wetlands were constructed in 1993-1994 in the Trebbia Valley (Piacenza, Italy). These plants worked as further treatment of secondary effluents of five little towns in the valley: Bobbio, Travo, Perino-Dolgo, Marsaglia, Ottone. The project and the realization considered the systems as Filtering Ecosystems and not a simple Aquatic Plant Systems. In 1994-1995 a research by University of Pavia was carried out, on the filtering ecosystem of Bobbio. Removal efficiency was 9,9 for phaecal coliforms, and 65% for nitrates.

Identification of phosphorylation sites in protein kinase A substrates using artificial neural networks and mass spectrometry

DEFF Research Database (Denmark)

Hjerrild, M.; Stensballe, A.; Rasmussen, T.E.

2004-01-01

Protein phosphorylation plays a key role in cell regulation and identification of phosphorylation sites is important for understanding their functional significance. Here, we present an artificial neural network algorithm: NetPhosK (http://www.cbs.dtu.dk/services/NetPhosK/) that predicts protein...

Identification of phosphorylation sites in protein kinase A substrates using artificial neural networks and mass spectrometry

DEFF Research Database (Denmark)

Hjerrild, Majbrit; Stensballe, Allan; Rasmussen, Thomas E

2011-01-01

Protein phosphorylation plays a key role in cell regulation and identification of phosphorylation sites is important for understanding their functional significance. Here, we present an artificial neural network algorithm: NetPhosK (http://www.cbs.dtu.dk/services/NetPhosK/) that predicts protein...

Selenite resistant rhizobacteria stimulate SeO(3) (2-) phytoextraction by Brassica juncea in bioaugmented water-filtering artificial beds.

Science.gov (United States)

Lampis, Silvia; Ferrari, Anita; Cunha-Queda, A Cristina F; Alvarenga, Paula; Di Gregorio, Simona; Vallini, Giovanni

2009-09-01

Selenium is a trace metalloid of global environmental concern. The boundary among its essentiality, deficiency, and toxicity is narrow and mainly depends on the chemical forms and concentrations in which this element occurs. Different plant species-including Brassica juncea-have been shown to play a significant role in Se removal from soil as well as water bodies. Furthermore, the interactions between such plants, showing natural capabilities of metal uptake and their rhizospheric microbial communities, might be exploited to increase both Se scavenging and vegetable biomass production in order to improve the whole phytoextraction efficiency. The aim of the present study was to evaluate the capability of selenite removal of B. juncea grown in hydroponic conditions on artificially spiked effluents. To optimize phytoextraction efficiency, interactions between B. juncea and rhizobacteria were designedly elicited. Firstly, B. juncea was grown on water-filtering agriperlite beds in the presence of three different selenite concentrations, namely, 0.2, 1.0, and 2.0 mM. Plant growth was measured after 3 and 6 weeks of incubation in order to establish the selenite concentration at which the best plant biomass production could be obtained. Afterwards, water-filtering agriperlite beds were inoculated either with a selenium-acclimated microbial community deriving from the rhizosphere of B. juncea grown, erstwhile, in a selenite-amended soil or with axenic cultures of two bacterial strains, vicelike Bacillus mycoides SeITE01 and Stenotrophomonas maltophilia SeITE02, previously isolated and described for their high resistance to selenite. These latter were seeded separately or as a dual consortium. Selenite was amended at a final concentration of 1.0 mM. Total Se content in plant tissues (both shoots and roots), plant biomass production, and persistence of bioaugmented microbial inocula during the experimental time were monitored. Moreover, parameters such as bioconcentration

Artificial Synaptic Devices Based on Natural Chicken Albumen Coupled Electric-Double-Layer Transistors.

Science.gov (United States)

Wu, Guodong; Feng, Ping; Wan, Xiang; Zhu, Liqiang; Shi, Yi; Wan, Qing

2016-03-24

Recent progress in using biomaterials to fabricate functional electronics has got growing attention for the new generation of environmentally friendly and biocompatible electronic devices. As a kind of biological material with rich source, proteins are essential natural component of all organisms. At the same time, artificial synaptic devices are of great significance for neuromorphic systems because they can emulate the signal process and memory behaviors of biological synapses. In this report, natural chicken albumen with high proton conductivity was used as the coupling electrolyte film for organic/inorganic hybrid synaptic devices fabrication. Some important synaptic functions including paired-pulse facilitation, dynamic filtering, short-term to long-term memory transition and spatial summation and shunting inhibition were successfully mimicked. Our results are very interesting for biological friendly artificial neuron networks and neuromorphic systems.

Artificial Synaptic Devices Based on Natural Chicken Albumen Coupled Electric-Double-Layer Transistors

Science.gov (United States)

Wu, Guodong; Feng, Ping; Wan, Xiang; Zhu, Liqiang; Shi, Yi; Wan, Qing

2016-03-01

Recent progress in using biomaterials to fabricate functional electronics has got growing attention for the new generation of environmentally friendly and biocompatible electronic devices. As a kind of biological material with rich source, proteins are essential natural component of all organisms. At the same time, artificial synaptic devices are of great significance for neuromorphic systems because they can emulate the signal process and memory behaviors of biological synapses. In this report, natural chicken albumen with high proton conductivity was used as the coupling electrolyte film for organic/inorganic hybrid synaptic devices fabrication. Some important synaptic functions including paired-pulse facilitation, dynamic filtering, short-term to long-term memory transition and spatial summation and shunting inhibition were successfully mimicked. Our results are very interesting for biological friendly artificial neuron networks and neuromorphic systems.

Digital Simulation of a Hybrid Active Filter - An Active Filter in Series with a Shunt Passive Filter

OpenAIRE

Sitaram, Mahesh I; Padiyar, KR; Ramanarayanan, V

1998-01-01

Active filters have long been in use for the filtering of power system load harmonics. In this paper, the digital simulation results of a hybrid active power filter system for a rectifier load are presented. The active filter is used for filtering higher order harmonics as the dominant harmonics are filtered by the passive filter. This reduces the rating of the active filter significantly. The DC capacitor voltage of the active filter is controlled using a PI controller.

Optically transparent frequency selective surfaces on flexible thin plastic substrates

Energy Technology Data Exchange (ETDEWEB)

Dewani, Aliya A., E-mail: a.ashraf@griffith.edu.au; O’Keefe, Steven G.; Thiel, David V.; Galehdar, Amir [School Of Electrical Engineering, Griffith University, Brisbane, 4111 (Australia)

2015-02-15

A novel 2D simple low cost frequency selective surface was screen printed on thin (0.21 mm), flexible transparent plastic substrate (relative permittivity 3.2). It was designed, fabricated and tested in the frequency range 10-20 GHz. The plane wave transmission and reflection coefficients agreed with numerical modelling. The effective permittivity and thickness of the backing sheet has a significant effect on the frequency characteristics. The stop band frequency reduced from 15GHz (no backing) to 12.5GHz with polycarbonate. The plastic substrate thickness beyond 1.8mm has minimal effect on the resonant frequency. While the inner element spacing controls the stop-band frequency, the substrate thickness controls the bandwidth. The screen printing technique provided a simple, low cost FSS fabrication method to produce flexible, conformal, optically transparent and bio-degradable FSS structures which can find their use in electromagnetic shielding and filtering applications in radomes, reflector antennas, beam splitters and polarizers.

Optically transparent frequency selective surfaces on flexible thin plastic substrates

Directory of Open Access Journals (Sweden)

Aliya A. Dewani

2015-02-01

Full Text Available A novel 2D simple low cost frequency selective surface was screen printed on thin (0.21 mm, flexible transparent plastic substrate (relative permittivity 3.2. It was designed, fabricated and tested in the frequency range 10-20 GHz. The plane wave transmission and reflection coefficients agreed with numerical modelling. The effective permittivity and thickness of the backing sheet has a significant effect on the frequency characteristics. The stop band frequency reduced from 15GHz (no backing to 12.5GHz with polycarbonate. The plastic substrate thickness beyond 1.8mm has minimal effect on the resonant frequency. While the inner element spacing controls the stop-band frequency, the substrate thickness controls the bandwidth. The screen printing technique provided a simple, low cost FSS fabrication method to produce flexible, conformal, optically transparent and bio-degradable FSS structures which can find their use in electromagnetic shielding and filtering applications in radomes, reflector antennas, beam splitters and polarizers.

Optically transparent frequency selective surfaces on flexible thin plastic substrates

Science.gov (United States)

Dewani, Aliya A.; O'Keefe, Steven G.; Thiel, David V.; Galehdar, Amir

2015-02-01

A novel 2D simple low cost frequency selective surface was screen printed on thin (0.21 mm), flexible transparent plastic substrate (relative permittivity 3.2). It was designed, fabricated and tested in the frequency range 10-20 GHz. The plane wave transmission and reflection coefficients agreed with numerical modelling. The effective permittivity and thickness of the backing sheet has a significant effect on the frequency characteristics. The stop band frequency reduced from 15GHz (no backing) to 12.5GHz with polycarbonate. The plastic substrate thickness beyond 1.8mm has minimal effect on the resonant frequency. While the inner element spacing controls the stop-band frequency, the substrate thickness controls the bandwidth. The screen printing technique provided a simple, low cost FSS fabrication method to produce flexible, conformal, optically transparent and bio-degradable FSS structures which can find their use in electromagnetic shielding and filtering applications in radomes, reflector antennas, beam splitters and polarizers.

Substrates and temperatures in the germination of Eriotheca gracilipes seeds

Directory of Open Access Journals (Sweden)

Paulo Alexandre Fernandes Rodrigues de Melo

Full Text Available ABSTRACT The Eriotheca gracilipes (K. Schum. A. Robyns is a forest specie that belongs to the Bombacaceae family and is considered an endemic specie from the Brazilian savanna. The aim of this study was to evaluate the best substrate and temperature for the vigor and germination test of E. gracilipes seeds. The experiment was carried out in a randomized design with a 4 x 7 factorial, with 28 treatments with the combination of four temperatures (20; 25; 30 and 20-30 ºC and seven substrates (coarse vermiculite, medium vermiculite, sand, Basaplant®, paper towel, on and between filter papers, with 4 repetitions of 25 seeds each. It was assessed germination, first count of germination, and germination speed index. In conclusion, for germination and vigor tests of Eriotheca gracilipes seeds it is recommended the paper roll as substrate at temperatures of 20-30, 25 or 30 ºC, and the Basaplant® and paper roll at the temperature of 30 ºC, respectively.

AER image filtering

Science.gov (United States)

Gómez-Rodríguez, F.; Linares-Barranco, A.; Paz, R.; Miró-Amarante, L.; Jiménez, G.; Civit, A.

2007-05-01

Address Event Representation (AER) is an emergent neuromorphic interchip communication protocol that allows real-time virtual massive connectivity among huge number of neurons located on different chips.[1] By exploiting high speed digital communication circuits (with nano-seconds timing), synaptic neural connections can be time multiplexed, while neural activity signals (with mili-seconds timings) are sampled at low frequencies. Neurons generate "events" according to their activity levels. That is, more active neurons generate more events per unit time and access the interchip communication channel more frequently than neurons with low activity. In Neuromorphic system development, AER brings some advantages to develop real-time image processing system: (1) AER represents the information like time continuous stream not like a frame; (2) AER sends the most important information first (although this depends on the sender); (3) AER allows to process information as soon as it is received. When AER is used in artificial vision field, each pixel is considered like a neuron, so pixel's intensity is represented like a sequence of events; modifying the number and the frequency of these events, it is possible to make some image filtering. In this paper we present four image filters using AER: (a) Noise addition and suppression, (b) brightness modification, (c) single moving object tracking and (d) geometrical transformations (rotation, translation, reduction and magnification). For testing and debugging, we use USB-AER board developed by Robotic and Technology of Computers Applied to Rehabilitation (RTCAR) research group. This board is based on an FPGA, devoted to manage the AER functionality. This board also includes a micro-controlled for USB communication, 2 Mbytes RAM and 2 AER ports (one for input and one for output).

A new collaborative recommendation approach based on users clustering using artificial bee colony algorithm.

Science.gov (United States)

Ju, Chunhua; Xu, Chonghuan

2013-01-01

Although there are many good collaborative recommendation methods, it is still a challenge to increase the accuracy and diversity of these methods to fulfill users' preferences. In this paper, we propose a novel collaborative filtering recommendation approach based on K-means clustering algorithm. In the process of clustering, we use artificial bee colony (ABC) algorithm to overcome the local optimal problem caused by K-means. After that we adopt the modified cosine similarity to compute the similarity between users in the same clusters. Finally, we generate recommendation results for the corresponding target users. Detailed numerical analysis on a benchmark dataset MovieLens and a real-world dataset indicates that our new collaborative filtering approach based on users clustering algorithm outperforms many other recommendation methods.

A New Collaborative Recommendation Approach Based on Users Clustering Using Artificial Bee Colony Algorithm

Directory of Open Access Journals (Sweden)

Chunhua Ju

2013-01-01

Full Text Available Although there are many good collaborative recommendation methods, it is still a challenge to increase the accuracy and diversity of these methods to fulfill users’ preferences. In this paper, we propose a novel collaborative filtering recommendation approach based on K-means clustering algorithm. In the process of clustering, we use artificial bee colony (ABC algorithm to overcome the local optimal problem caused by K-means. After that we adopt the modified cosine similarity to compute the similarity between users in the same clusters. Finally, we generate recommendation results for the corresponding target users. Detailed numerical analysis on a benchmark dataset MovieLens and a real-world dataset indicates that our new collaborative filtering approach based on users clustering algorithm outperforms many other recommendation methods.

PENGARUH PERLAKUAN DELIGNIFIKASI DENGAN LARUTAN NAOH DAN KONSENTRASI SUBSTRAT JERAMI PADI TERHADAP PRODUKSI ENZIM SELULASE DARI ASPERGILLUS NIGER NRRL A-II, 264

Directory of Open Access Journals (Sweden)

IDA BAGUS WAYAN GUNAM

2010-12-01

Full Text Available his research was done in order to utilize agricultural waste (rice straw as substrate to produce crude cellulase enzyme from Aspergillus niger. This research was conducted in two stages; the first stage was determination of the initial pH and fermentation time by pH treatment (5, 6 and 7 and fermentation time (7, 9 and 11 days. The second stage was determination of concentration of NaOH treatment and concentration of substrate, namely: concentrations of NaOH (2, 4 and 6% and concentrations of substrate (1, 2 and 3% (w/v. The results showed that the fermentation time of 9 days with the initial pH 6.0 was the optimal condition for production of crude cellulase enzyme from A. niger with rice straw as a substrate. The highest enzyme activity derived from interaction of delignification treatment with NaOH concentration of 6% and 2% rice straw substrate which produces endoglukanase enzyme activity (0.037 units/ml, filter paperase activity (0.033 units/ml, soluble protein (0.362 mg/ml, and specific activity of filter paperase (0.123 units/mg.

Photostability of cosmetic UV filters on mammalian skin under UV exposure.

Science.gov (United States)

Stiefel, Constanze; Schwack, Wolfgang; Nguyen, Yen-Thi Hai

2015-01-01

Previous studies showed that the common UV filter substances benzophenone-3 (BP-3), butyl methoxydibenzoylmethane (BM-DBM), octocrylene (OCR), ethylhexyl methoxycinnamate (EHMC), ethylhexyl salicylate (EHS) and ethylhexyl triazone (EHT) were able to react with amino side chains of different proteins in vitro. To transfer the results to mammalian skin conditions, sunscreen products were applied on both prepared fresh porcine skin and glass plates, followed by UV irradiation and the determination of depletion of the respective UV filters. Significantly lower recoveries of the UV filters extracted from skin samples than from glass plates indicated the additional reaction of the UV filters with skin constituents, when proteins will be the most important reactants. Among the products tested, BP-3 showed the greatest differences in recoveries between glass and skin samples of about 13% and 24% after 2 and 4 h of irradiation, respectively, followed by EHS > BM-DBM > OCR > EHMC > EHT. The obtained results raise the question, whether the common in vitro evaluations of sunscreens, using inert substrate materials like roughened quartz or polymethyl methacrylate (PMMA) plates are really suitable to fully replace in vivo methods, as they cannot include skin-typical reactions. © 2014 The American Society of Photobiology.

GaN thin films on SiC substrates studied using variable energy positron annihilation spectroscopy

International Nuclear Information System (INIS)

Hu, Y.F.; Shan, Y.Y.; Beling, C.D.; Fung, S.; Xie, M.H.; Cheung, S.H.; Tu, J.; Tong, D.S.Y.

2001-01-01

A variety of GaN epilayers, grown on 6H-SiC substrates using different growth conditions, have been studied using variable energy positron annihilation spectroscopy. In the S-E plots, a peak structure in the S-parameter is seen which is related to the GaN/substrate heterojunction. The position of the peak is found to be much closer to the sample surface than expected from simple mean implantation depth arguments. This anomaly is attributed to the fact that there is a rectifying potential step that prevents diffusing positrons in the GaN from entering the SiC substrate. This effect has been successfully mimicked by inserting an artificial electric field into the thin interfacial region in the VEPFIT analysis. (orig.)

3D early embryogenesis image filtering by nonlinear partial differential equations.

Science.gov (United States)

Krivá, Z; Mikula, K; Peyriéras, N; Rizzi, B; Sarti, A; Stasová, O

2010-08-01

are artificially connected due to acquisition error intrinsically linked to physics of LSM. In all studied aspects it turned out that the nonlinear diffusion filter which is called geodesic mean curvature flow (GMCF) has the best performance. Copyright 2010 Elsevier B.V. All rights reserved.

Are artificial opals non-close-packed fcc structures?

Science.gov (United States)

García-Santamaría, F.; Braun, P. V.

2007-06-01

The authors report a simple experimental method to accurately measure the volume fraction of artificial opals. The results are modeled using several methods, and they find that some of the most common yield very inaccurate results. Both finite size and substrate effects play an important role in calculations of the volume fraction. The experimental results show that the interstitial pore volume is 4%-15% larger than expected for close-packed structures. Consequently, calculations performed in previous work relating the amount of material synthesized in the opal interstices with the optical properties may need revision, especially in the case of high refractive index materials.

Filter assembly for metallic and intermetallic tube filters

Science.gov (United States)

Alvin, Mary Anne; Lippert, Thomas E.; Bruck, Gerald J.; Smeltzer, Eugene E.

2001-01-01

A filter assembly (60) for holding a filter element (28) within a hot gas cleanup system pressure vessel is provided, containing: a filter housing (62), said filter housing having a certain axial length and having a peripheral sidewall, said sidewall defining an interior chamber (66); a one piece, all metal, fail-safe/regenerator device (68) within the interior chamber (66) of the filter housing (62) and/or extending beyond the axial length of the filter housing, said device containing an outward extending radial flange (71) within the filter housing for seating an essential seal (70), the device also having heat transfer media (72) disposed inside and screens (80) for particulate removal; one compliant gasket (70) positioned next to and above the outward extending radial flange of the fail-safe/regenerator device; and a porous metallic corrosion resistant superalloy type filter element body welded at the bottom of the metal fail-safe/regenerator device.

Statistically-Efficient Filtering in Impulsive Environments: Weighted Myriad Filters

Directory of Open Access Journals (Sweden)

Juan G. Gonzalez

2002-01-01

Full Text Available Linear filtering theory has been largely motivated by the characteristics of Gaussian signals. In the same manner, the proposed Myriad Filtering methods are motivated by the need for a flexible filter class with high statistical efficiency in non-Gaussian impulsive environments that can appear in practice. Myriad filters have a solid theoretical basis, are inherently more powerful than median filters, and are very general, subsuming traditional linear FIR filters. The foundation of the proposed filtering algorithms lies in the definition of the myriad as a tunable estimator of location derived from the theory of robust statistics. We prove several fundamental properties of this estimator and show its optimality in practical impulsive models such as the α-stable and generalized-t. We then extend the myriad estimation framework to allow the use of weights. In the same way as linear FIR filters become a powerful generalization of the mean filter, filters based on running myriads reach all of their potential when a weighting scheme is utilized. We derive the “normal” equations for the optimal myriad filter, and introduce a suboptimal methodology for filter tuning and design. The strong potential of myriad filtering and estimation in impulsive environments is illustrated with several examples.

Filter material charging apparatus for filter assembly for radioactive contaminants

International Nuclear Information System (INIS)

Goldsmith, J.M.; O'Nan, A. Jr.

1977-01-01

A filter charging apparatus for a filter assembly is described. The filter assembly includes a housing with at least one filter bed therein and the filter charging apparatus for adding filter material to the filter assembly includes a tank with an opening therein, the tank opening being disposed in flow communication with opposed first and second conduit means, the first conduit means being in flow communication with the filter assembly housing and the second conduit means being in flow communication with a blower means. Upon activation of the blower means, the blower means pneumatically conveys the filter material from the tank to the filter housing

Gain Enhanced On-Chip Folded Dipole Antenna Utilizing Artificial Magnetic Conductor at 94 GHz

KAUST Repository

Nafe, Mahmoud; Syed, Ahad; Shamim, Atif

2017-01-01

On-chip antennas suffer from low gain values and distorted radiation patterns due to lossy and high permittivity Si substrate. An ideal solution would be to isolate the lossy Si substrate from the antenna through a Perfect Electric Conductor (PEC) ground plane, however the typical CMOS stack up which has multiple metal layers embedded in a thin oxide layer does not permit this. In this work, an Artificial Magnetic Conductor (AMC) reflecting surface has been utilized to isolate the Si substrate from the antenna. Contrary to the previous reports, the AMC structure is completely embedded in the thin oxide layer with the ground plane above the Si substrate. In this approach, the AMC surface acts for the first time as both a reflector and a silicon shield. As a result the antenna radiation pattern is not distorted and its gain is improved by 8 dB. The fabricated prototype demonstrates good impedance and radiation characteristics.

Gain Enhanced On-Chip Folded Dipole Antenna Utilizing Artificial Magnetic Conductor at 94 GHz

KAUST Repository

Nafe, Mahmoud

2017-09-05

On-chip antennas suffer from low gain values and distorted radiation patterns due to lossy and high permittivity Si substrate. An ideal solution would be to isolate the lossy Si substrate from the antenna through a Perfect Electric Conductor (PEC) ground plane, however the typical CMOS stack up which has multiple metal layers embedded in a thin oxide layer does not permit this. In this work, an Artificial Magnetic Conductor (AMC) reflecting surface has been utilized to isolate the Si substrate from the antenna. Contrary to the previous reports, the AMC structure is completely embedded in the thin oxide layer with the ground plane above the Si substrate. In this approach, the AMC surface acts for the first time as both a reflector and a silicon shield. As a result the antenna radiation pattern is not distorted and its gain is improved by 8 dB. The fabricated prototype demonstrates good impedance and radiation characteristics.

Novel fabrication method of the peritoneal dialysis filter using silk fibroin with urease fixation system.

Science.gov (United States)

Moon, Bo Mi; Choi, Myung-Jin; Sultan, Md Tipu; Yang, Jae Won; Ju, Hyung Woo; Lee, Jung Min; Park, Hyun Jung; Park, Ye Ri; Kim, Soo Hyeon; Kim, Dong Wook; Lee, Min Chae; Jeong, Ju Yeon; Lee, Ok Joo; Sung, Gun Yong; Park, Chan Hum

2017-10-01

During the last decade, there has been a great advance in the kidney dialysis system by wearable artificial kidney (WAK) system for end-stage renal disease patients. Uremic solute removal and water regeneration system are the most prerequisite for WAK to work properly. In this study, we designed a filtering membrane system by using immobilized urease silk fibroin filter and evaluated its comparative effectiveness with a PVDF filtering system in peritoneal dialysate regeneration system by urea removal efficacy. We evaluated this membrane's characteristic and performances by conducting SEM-EDX analyze, water-binding abilities and porosity test, removal abilities of urea, cytotoxicity assay and enzyme activity assay. Under the condition for optimization of urease, the percentage removal of urea was about 40% and 60% in 50 mg/dL urea solution by urease immobilized PVDF and silk fibroin scaffolds, respectively. The batch experimental result showed that immobilized filter removed more than 50% of urea in 50 mg/dL urea solution. In addition silk fibroin with urease filter removed 90 percent of urea in the peritoneal dialysate after 24 h filtration. We suggest that silk fibroin with urease fixation filter can be used more effectively for peritoneal dialysate regeneration system, which have hydrophilic property and prolonged enzyme activity. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2136-2144, 2017. © 2016 Wiley Periodicals, Inc.

Control of a hybrid compensator in a power network by an artificial neural network

Directory of Open Access Journals (Sweden)

I. S. Shaw

1998-07-01

Full Text Available Increased interest in the elimination of distortion in electrical power networks has led to the development of various compensator topologies. The increasing cost of electrical energy necessitates the cost-effective operation of any of these topologies. This paper considers the development of an artificial neural network based controller, trained by means of the backpropagation method, that ensures the cost-effective operation of the hybrid compensator consisting of various converters and filters.

A novel filtering mutualism between a sponge host and its endosymbiotic bivalves.

Science.gov (United States)

Tsubaki, Remi; Kato, Makoto

2014-01-01

Sponges, porous filter-feeding organisms consisting of vast canal systems, provide unique substrates for diverse symbiotic organisms. The Spongia (Spongia) sp. massive sponge is obligately inhabited by the host-specific endosymbiotic bivalve Vulsella vulsella, which benefits from this symbiosis by receiving protection from predators. However, whether the host sponge gains any benefit from this association is unclear. Considering that the bivalves exhale filtered water into the sponge body rather than the ambient environment, the sponge is hypothesized to utilize water exhaled by the bivalves to circulate water around its body more efficiently. We tested this hypothesis by observing the sponge aquiferous structure and comparing the pumping rates of sponges and bivalves. Observations of water currents and the sponge aquiferous structure revealed that the sponge had a unique canal system enabling it to inhale water exhaled from bivalves, indicating that the host sponge adapted morphologically to receive water from the bivalves. In addition, the volume of water circulating in the sponge body was dramatically increased by the water exhaled from bivalves. Therefore, this sponge-bivalve association can be regarded as a novel mutualism in which two filter-feeding symbionts promote mutual filtering rates. This symbiotic association should be called a "filtering mutualism".

Three-State Locally Adaptive Texture Preserving Filter for Radar and Optical Image Processing

Directory of Open Access Journals (Sweden)

Jaakko T. Astola

2005-05-01

Full Text Available Textural features are one of the most important types of useful information contained in images. In practice, these features are commonly masked by noise. Relatively little attention has been paid to texture preserving properties of noise attenuation methods. This stimulates solving the following tasks: (1 to analyze the texture preservation properties of various filters; and (2 to design image processing methods capable to preserve texture features well and to effectively reduce noise. This paper deals with examining texture feature preserving properties of different filters. The study is performed for a set of texture samples and different noise variances. The locally adaptive three-state schemes are proposed for which texture is considered as a particular class. For “detection” of texture regions, several classifiers are proposed and analyzed. As shown, an appropriate trade-off of the designed filter properties is provided. This is demonstrated quantitatively for artificial test images and is confirmed visually for real-life images.

Design of 2.5 GHz broad bandwidth microwave bandpass filter at operating frequency of 10 GHz using HFSS

Science.gov (United States)

Jasim, S. E.; Jusoh, M. A.; Mahmud, S. N. S.; Zamani, A. H.

2018-04-01

Development of low losses, small size and broad bandwidth microwave bandpass filter operating at higher frequencies is an active area of research. This paper presents a new route used to design and simulate microwave bandpass filter using finite element modelling and realized broad bandwidth, low losses, small dimension microwave bandpass filter operating at 10 GHz frequency using return loss method. The filter circuit has been carried out using Computer Aid Design (CAD), Ansoft HFSS software and designed with four parallel couple line model and small dimension (10 × 10 mm2) using LaAlO3 substrate. The response of the microwave filter circuit showed high return loss -50 dB at operating frequency at 10.4 GHz and broad bandwidth of 2.5 GHz from 9.5 to 12 GHz. The results indicate the filter design and simulation using HFSS is reliable and have the opportunity to transfer from lab potential experiments to the industry.

Poliuretana derivada de óleos vegetais exposta ao intemperismo artificial Polyurethane derived from vegetal oil exposed to artificial weathering

Directory of Open Access Journals (Sweden)

Alessandra E. F. S. Almeida

2006-01-01

Full Text Available Foram obtidas as propriedades mecânicas e viscoelásticas da poliuretana derivada do óleo de mamona após sua exposição ao intemperismo artificial, a fim de avaliar a aplicabilidade deste material como revestimento polimérico para substratos de concreto na Construção Civil. Os procedimentos experimentais foram realizados em conformidade com a ASTM G 53 for "Operating Light and Water Exposure Apparatus (Fluorescent UV - Condensation Type for Exposure of Nonmetallic Materials"[1]. O ensaio para a caracterização mecânica dos corpos-de-prova após exposição ao intemperismo artificial foi realizado conforme a norma ASTM D 638M-96 "Standard Test Method for Tensile Properties of Plastics (Metric"[2]. Foi empregado o método de análise dinâmico-mecânica para a obtenção das propriedades viscoelásticas da poliuretana vegetal. Os resultados mostraram que a exposição ao intemperismo artificial não ocasionou mudanças significativas nas propriedades do revestimento polimérico para o tempo de exposição estudado.The mechanical and viscoelastic properties of polyurethane derived from castor oil were obtained after being exposed to artificial weathering with the purpose of evaluating their applicability as polymeric coatings on concrete substrate for Civil Construction. The procedures followed the ASTM G53 for "Operating Light and Water Exposure Apparatus (Fluorescent UV - Condensation Type for Exposure of Nonmetallic Materials"[1]. Mechanical properties were obtained by means of the ASTM D 638M-96 "Standard Test Method for Tensile Properties of Plastics (Metric"[2]. Furthermore, a Dynamic Mechanical Analysis (DMA was carried out in order to study the viscoelastic properties of polyurethane. The results showed that the properties were altered slightly considering the time studied.

Bank filtered water quality characteristics in Okgog-Ri area of Youngsan-River, Korea

Energy Technology Data Exchange (ETDEWEB)

Park, Hee-Youl; Kim, Hyoung-Soo [Korea Water Resources Corp., Taejeon(Korea)

2001-02-28

Preliminary artificial recharge groundwater intake method using bank filtering had been conducted in Okgog-Ri of Youngsan-River to evaluate the possibility of substitution of surface water intake method in the area. In order to investigate the characteristics of bank filtered groundwater, we examined the hydrogeological properties of alluvium and water quality of stream and groundwater. It is observed that nitrate in stream water from synthetic fertilizer and poultry manure is almost consumed during bank filtering in this area. This implies that denitrification of organic carbon and the oxidation of pyrite present in the alluvium aquifer. Groundwater samples from bank filtering show high Mn concentration. This high Mn concentration may be resulted from decreasing redox potential due to denitrification and increasing mobility due to redox reaction of Mn-oxide. In the study area, there is a typical tendency that Al concentrations of water samples decrease according to increasing pH. This tendency is interpreted as forming of amorphous Al(OH){sub 3} precipitates by reducing the Al{sup 3+} solubilities. It is revealed that the bank filtered groundwater in the area is not edible because color, turbidity, heterotrophic bacteria, coliform and Mn of the groundwater exceed the guideline of drinking water. Even though the bank filtered groundwater without treatment does not satisfy the guideline of drinking water, the groundwater shows a good water quality compared with stream water. So, the water treatment method using bank filtered groundwater can be more economical and efficient than the treatment using direct intake of stream water in the aspect of water quality. (author). 15 refs., 2 tabs., 7 figs.

Fabricating high-resolution offset color-filter black matrix by integrating heterostructured substrate with inkjet printing

International Nuclear Information System (INIS)

Lu, Guo-Shin; You, Po-Chin; Lin, Kai-Lun; Hong, Chien-Chong; Liou, Tong-Miin

2014-01-01

This paper presents a self-aligning ink by integrating an inkjet printing technique and heterostructures to fabricate a black matrix with a micrometer-scale tunable thickness. The black matrix is a grid-like structure used in color filters. Traditionally, a black matrix has been fabricated using photolithography techniques, the disadvantages of which are high material consumption, less fabrication flexibility, complex processing procedures, and high chemical pollution. Inkjet printing technology has garnered attention because of its low material costs, high fabrication flexibility, and reduced processing procedures and pollution. In this study, a fabricating process combining an inkjet printing technique with heterostructures to form stripe-arranged and delta-arranged thickness-tunable black matrices has been demonstrated. The deformation and self-aligning process of ink droplet impingement onto gutters are driven by designed heterogeneous surface properties. The minimum track width attained is 10 µm, which is competitive for color filter resolutions for thin-film transistor liquid crystal displays. The developed technology surmounts the bottlenecks of inkjet printing resolution, and saves more than 75% black material than modern photolithography. (paper)

Synthesis of highly integrated optical network based on microdisk-resonator add-drop filters in silicon-on-insulator technology

Science.gov (United States)

Kaźmierczak, Andrzej; Dortu, Fabian; Giannone, Domenico; Bogaerts, Wim; Drouard, Emmanuel; Rojo-Romeo, Pedro; Gaffiot, Frederic

2009-10-01

We analyze a highly compact optical add-drop filter topology based on a pair of microdisk resonators and a bus waveguide intersection. The filter is further assessed on an integrated optical 4×4 network for optical on-chip communication. The proposed network structure, as compact as 50×50 μm, is fabricated in a CMOS-compatible process on a silicon-on-insulator (SOI) substrate. Finally, the experimental results demonstrate the proper operation of the fabricated devices.

Use of artificial intelligence to analyze clinical database reduces workload on surgical house staff.

Science.gov (United States)

Grossi, E A; Steinberg, B M; LeBoutillier, M; Coppa, G F; Roses, D F

1994-08-01

The current quantity and diversity of hospital clinical, laboratory, and pharmacy records have resulted in a glut of information, which can be overwhelming to house staff. This study was performed to measure the impact of artificial intelligence analysis of such data on the junior surgical house staff's workload, time for direct patient care, and quality of life. A personal computer was interfaced with the hospital computerized patient data system. Artificial intelligence algorithms were applied to retrieve and condense laboratory values, microbiology reports, and medication orders. Unusual laboratory tests were reported without artificial intelligence filtering. A survey of 23 junior house staff showed a requirement for a total of 30.75 man-hours per day, an average of 184.5 minutes per service twice a day for five surgical services each with an average of 40.7 patients, to manually produce a report in contrast to a total of 3.4 man-hours, an average of 20.5 minutes on the same basis (88.9% reduction, p medical practice has created an explosion of information, which is a burden for surgical house staff. Artificial intelligence preprocessing of the hospital database information focuses attention, eliminates superfluous data, and significantly reduces surgical house staff clerical work, allowing more time for education, research, and patient care.

Comparison among Wavelet filters and others in the frequency domain for reducing Poisson noise in head CT

International Nuclear Information System (INIS)

Perez Diaz, M.; Ruiz Gonzalez, Y.; Lorenzo Ginori, J. V.

2015-01-01

This paper describes a comparison among some wavelet filters and other most traditional filters in the frequency domain like Median, Wiener and Butter worth to reduce Poisson noise in Computed Tomography (CT) scans. Five slices of CT containing the posterior fossa from an anthropomorphic phantom and from patients were selected. As their original projections contain noise from the acquisition process, some simulated noise-free lesions were added on the images. After that, the whole images were artificially contaminated with Poisson noise over the sinogram-space. The configurations using wavelets drawn from four wavelet families, using various decomposition levels, and different thresholds, were tested in order to determine de-noising performance as well as the rest of the traditional filters. The quality of the resulting images was evaluated by using Contrast to Noise Ratio (CNR), HVS absolute norm (H1), and Structural Similarity Index (SSIM) as quantitative metrics. We have observed that Wavelet filtering is an alternative to be considered for Poisson noise reduction in image processing of posterior fossa images for head CT with similar behavior to Butter worth and better than Median or Wiener filters for the developed experiment. (Author)

Selecting the optimal anti-aliasing filter for multichannel biosignal acquisition intended for inter-signal phase shift analysis

International Nuclear Information System (INIS)

Keresnyei, Róbert; Hejjel, László; Megyeri, Péter; Zidarics, Zoltán

2015-01-01

The availability of microcomputer-based portable devices facilitates the high-volume multichannel biosignal acquisition and the analysis of their instantaneous oscillations and inter-signal temporal correlations. These new, non-invasively obtained parameters can have considerable prognostic or diagnostic roles. The present study investigates the inherent signal delay of the obligatory anti-aliasing filters. One cycle of each of the 8 electrocardiogram (ECG) and 4 photoplethysmogram signals from healthy volunteers or artificially synthesised series were passed through 100–80–60–40–20 Hz 2–4–6–8th order Bessel and Butterworth filters digitally synthesized by bilinear transformation, that resulted in a negligible error in signal delay compared to the mathematical model of the impulse- and step responses of the filters. The investigated filters have as diverse a signal delay as 2–46 ms depending on the filter parameters and the signal slew rate, which is difficult to predict in biological systems and thus difficult to compensate for. Its magnitude can be comparable to the examined phase shifts, deteriorating the accuracy of the measurement. As a conclusion, identical or very similar anti-aliasing filters with lower orders and higher corner frequencies, oversampling, and digital low pass filtering are recommended for biosignal acquisition intended for inter-signal phase shift analysis. (note)

Bio-Inspired Assembly of Artificial Photosynthetic Antenna Complexes for Development of Nanobiodevices

Science.gov (United States)

2011-06-24

complexes involved in the primary reactions of bacterial photosynthesis . The structure of the reaction center (RC, the first membrane protein to have its...role in the primary process of purple bacterial photosynthesis that is, capturing light energy, transferring it to the RC where it is used in...immobilization LH2 LH1-RC AFM image of a bacterial photosynthetic membrane . Artificial domains of LH2 & LH1-RC with patterning substrate Modern

Integration of Artificial Neural Network Modeling and Genetic Algorithm Approach for Enrichment of Laccase Production in Solid State Fermentation by Pleurotus ostreatus

OpenAIRE

Potu Venkata Chiranjeevi; Moses Rajasekara Pandian; Sathish Thadikamala

2014-01-01

Black gram husk was used as a solid substrate for laccase production by Pleurotus ostreatus, and various fermentation conditions were optimized based on an artificial intelligence method. A total of six parameters, i.e., temperature, inoculum concentration, moisture content, CuSO4, glucose, and peptone concentrations, were optimized. A total of 50 experiments were conducted, and the obtained data were modeled by a hybrid of artificial neural network (ANN) and genetic algorithm (GA) approaches...

A Design of a Terahertz Microstrip Bandstop Filter with Defected Ground Structure

Directory of Open Access Journals (Sweden)

Arjun Kumar

2013-01-01

Full Text Available A planar microstrip terahertz (THz bandstop filter has been proposed with defected ground structure with high insertion loss (S21 in a stopband of −25.8 dB at 1.436 THz. The parameters of the circuit model have been extracted from the EM simulation results. A dielectric substrate of Benzocyclobutene (BCB is used to realize a compact bandstop filter using modified hexagonal dumbbell-shape defected ground structure (DB-DGS. In this paper, a defected ground structure topology is used in a λ/4, 50 Ω microstrip line at THz frequency range for compactness. No article has been reported on the microstrip line at terahertz frequency regime using DGS topology. The proposed filter can be used for sensing and detection in biomedical instruments in DNA testing. All the simulations/cosimulations are carried out using a full-wave EM simulator CST V.9 Microwave Studio, HFSS V.10, and Agilent Design Suite (ADS.

Artificial skin and patient simulator comprising the artificial skin

NARCIS (Netherlands)

2011-01-01

The invention relates to an artificial skin (10, 12, 14), and relates to a patient simulator (100) comprising the artificial skin. The artificial skin is a layered structure comprising a translucent cover layer (20) configured for imitating human or animal skin, and comprising a light emitting layer

Artificial Intelligence.

Science.gov (United States)

Information Technology Quarterly, 1985

1985-01-01

This issue of "Information Technology Quarterly" is devoted to the theme of "Artificial Intelligence." It contains two major articles: (1) Artificial Intelligence and Law" (D. Peter O'Neill and George D. Wood); (2) "Artificial Intelligence: A Long and Winding Road" (John J. Simon, Jr.). In addition, it contains two sidebars: (1) "Calculating and…

Recycle of enzymes and substrate following enzymatic hydrolysis of steam-pretreated aspenwood

Energy Technology Data Exchange (ETDEWEB)

Mes-Hartree, M.; Hogan, C.M.; Saddler, J.N.

1987-09-01

The commercial production of chemicals and fuels from lignocellulosic residues by enzymatic means still requires considerable research on both the technical and economic aspects. Two technical problems that have been identified as requiring further research are the recycle of the enzymes used in hydrolysis and the reuse of the recalcitrant cellulose remaining after incomplete hydrolysis. Enzyme recycle is required to lower the cost of the enzymes, while the reuse of the spent cellulose will lower the feedstock cost. The conversion process studied was a combined enzymatic hydrolysis and fermentation (CHF) procedure that utilized the cellulolytic enzymes derived from the fungus Trichoderma harzianum E58 and the yeast Saccharomyces cerevisiae. The rate and extent of hydrolysis and ethanol production was monitored as was the activity and hydrolytic potential of the enzymes remaining in the filtrate after the hydrolysis period. When a commercial cellulose was used as the substrate for a routine 2-day CHF process, 60% of the original filter paper activity could be recovered. When steam-treated, water-extracted aspenwood was used as the substrate, only 13% of the original filter paper activity was detected after a similar procedure. The combination of 60% spent enzymes with 40% fresh enzymes resulted in the production of 30% less reducing sugars than the original enzyme mixture. Since 100% hydrolysis of the cellulose portion is seldom accomplished in an enzymatic hydrolysis process, the residual cellulose was used as a substrate for the growth of T. harzianum E58 and production of cellulolytic enzymes. The residue remaining after the CHF process was used as a substrate for the production of the cellulolytic enzymes. The production of enzymes from the residue of the Solka Floc hydrolysis was greater than the production of enzymes from the original Solka Floc. (Refs. 14).

Selective light sintering of Aerosol-Jet printed silver nanoparticle inks on polymer substrates

International Nuclear Information System (INIS)

Schuetz, K.; Hoerber, J.; Franke, J.

2014-01-01

Printing silver nanoparticle inks to generate conductive structures for electronics on polymer substrates has gained increasing relevance in recent years. In this context, the Aerosol-Jet Technology is well suited to print silver ink on 3D-Molded Interconnect Devices (MID). The deposited ink requires thermal post-treatment to obtain sufficient electrical conductivity and adhesion. However, commonly used oven sintering cannot be applied for many thermoplastic substrates due to low melting temperatures. In this study a new sintering technology, selective light sintering, is presented, based on the focused, continuous light beam of a xenon lamp. Sintering experiments were conducted with Aerosol-Jet printed structures on various polycarbonate (PC) substrates. Especially on neat, light transparent PC, silver tracks were evenly sintered with marginal impact to the substrate. Electrical conductivities significantly exceed the values obtained with conventional oven sintering. Adhesive strength is sufficient for conductive tracks. Experiments with non-transparent PC substrates led to substrate damage due to increased light absorption. Therefore a concept for a variation of light sintering was developed, using optical filters. First experiments showed significant reduction of substrate damage and good sintering qualities. The highly promising results of the conducted experiments provide a base for further investigations to increase adhesion and qualifying the technology for MID applications and a broad spectrum of thermoplastic substrates

Artificial nacre-like papers based on noncovalent functionalized boron nitride nanosheets with excellent mechanical and thermally conductive properties.

Science.gov (United States)

Zeng, Xiaoliang; Ye, Lei; Yu, Shuhui; Li, Hao; Sun, Rong; Xu, Jianbin; Wong, Ching-Ping

2015-04-21

Inspired by the nano/microscale hierarchical structure and the precise inorganic/organic interface of natural nacre, we fabricated artificial nacre-like papers based on noncovalent functionalized boron nitride nanosheets (NF-BNNSs) and poly(vinyl alcohol) (PVA) via a vacuum-assisted self-assembly technique. The artificial nacre-like papers exhibit excellent tensile strength (125.2 MPa), on a par with that of the natural nacre, and moreover display a 30% higher toughness (2.37 MJ m(-3)) than that of the natural nacre. These excellent mechanical properties result from an ordered 'brick-and-mortar' arrangement of NF-BNNSs and PVA, in which the long-chain PVA molecules act as the bridge to link NF-BNNSs via hydrogen bonds. The resulting papers also render high thermal conductivity (6.9 W m(-1) K(-1)), and reveal their superiority as flexible substrates to support light-emitting-diode chips. The combined mechanical and thermal properties make the materials highly desirable as flexible substrates for next-generation commercial portable electronics.

Artificial organs: recent progress in artificial hearing and vision.

Science.gov (United States)

Ifukube, Tohru

2009-01-01

Artificial sensory organs are a prosthetic means of sending visual or auditory information to the brain by electrical stimulation of the optic or auditory nerves to assist visually impaired or hearing-impaired people. However, clinical application of artificial sensory organs, except for cochlear implants, is still a trial-and-error process. This is because how and where the information transmitted to the brain is processed is still unknown, and also because changes in brain function (plasticity) remain unknown, even though brain plasticity plays an important role in meaningful interpretation of new sensory stimuli. This article discusses some basic unresolved issues and potential solutions in the development of artificial sensory organs such as cochlear implants, brainstem implants, artificial vision, and artificial retinas.

Paper based Flexible and Conformal SERS Substrate for Rapid Trace Detection on Real-world Surfaces

Science.gov (United States)

Singamaneni, Srikanth; Lee, Chang; Tian, Limei

2011-03-01

One of the important but often overlooked considerations in the design of surface enhanced Raman scattering (SERS) substrates for trace detection is the efficiency of sample collection. Conventional designs based on rigid substrates such as silicon, alumina, and glass resist conformal contact with the surface under investigation, making the sample collection inefficient. We demonstrate a novel SERS substrate based on common filter paper adsorbed with gold nanorods, which allows conformal contact with real-world surfaces, thus dramatically enhancing the sample collection efficiency compared to conventional rigid substrates. We demonstrate the detection of trace amounts of analyte (140 pg spread over 4 cm2) by simply swabbing the surface under investigation with the novel SERS substrate. The hierarchical fibrous structure of paper serves as a 3D vasculature for easy uptake and transport of the analytes to the electromagnetic hot spots in the paper. Simple yet highly efficient and cost effective SERS substrate demonstrated here brings SERS based trace detection closer to real-world applications. We acknowledge the financial support from Center for Materials Innovation at Washington University.

Design and fabrication of bandwidth tunable HTS transmit filter using {pi}-shaped waveguides

Energy Technology Data Exchange (ETDEWEB)

Sekiya, N., E-mail: nsekiya@yamanashi.ac.j [Department of Electrical Engineering, Yamanashi University, Nakagawa-Sekiya Laboratory, 4-3-11 Takeda, Kofu 400-8511 (Japan); Harada, H.; Nakagawa, Y. [Department of Electrical Engineering, Yamanashi University, Nakagawa-Sekiya Laboratory, 4-3-11 Takeda, Kofu 400-8511 (Japan); Ono, S.; Ohshima, S. [Yamagata University, 4-3-16 Johnan, Yonezawa 992-8510 (Japan)

2010-11-01

We have developed a method for tuning the bandwidth of a high-temperature superconducting (HTS) microstrip filter. Several {pi}-shaped waveguides are placed between the resonators, and the bandwidth is tuned in discrete steps by changing the switch states of the waveguides, which changes the coupling coefficient between the resonators. The filter contains 3-pole half-wavelength straight-line resonators and two {pi}-shaped waveguides for bandwidth tuning. It also has several electrical pads distributed around the feed lines for trimming after tuning. The filter was fabricated by depositing YBa{sub 2}Cu{sub 3}O{sub 7} thin film on an MgO substrate and has a measured center frequency of 5.17 GHz and bandwidth of 220 MHz. Use of the {pi}-shaped waveguides to adjust the coupling coefficients and the electrical pads to adjust the external quality factors resulted in 80-MHz bandwidth tuning without increased insertion loss.

Design and characteristics of L-C thin films filter at microwave frequency band

Science.gov (United States)

Kim, In-Sung; Min, Bok-Ki; Song, Jae-Sung

2005-12-01

Multifunction corresponding to multimedia age has furthermore required high integration to the devices at microwave band, so more evolution for multi-layer integration like system on chip(SoC) becomes to be necessary. In wireless mobile communication, portable mobile phones grew up to a huge market. Microwave devices have played an important role in the wireless communication systems. One challenge in the implementation of circuit integration is in the design of micro wave band pass filter with thin film MOM capacitor and spiral inductor. In this paper, Cu and TaO thin film with RF sputtering was deposited for inductor and capacitor on the SiO II/Si(100) substrate. MIM capacitor and spiral inductor was fabricated for L-C band pass filter by sputtering and lift-off. We are analyzed and designed thin films L-C passive components for band pass filter at 900 MHz and 1.8 GHz, an important devices for mobile communication. Based on the high-Q values of passive components, MIM capacitor and spiral inductors for L-C band pass filter, a low insertion loss of L-C passive components can be realized with a minimized chip area. The insertion loss was 3 dB for a 1.8 GHz filter, and was 5 dB for a 900 MHz filter. This paper also discusses a theoretical analysis and practical design to L-C band pass filter.

Optimal digital filtering for tremor suppression.

Science.gov (United States)

Gonzalez, J G; Heredia, E A; Rahman, T; Barner, K E; Arce, G R

2000-05-01

Remote manually operated tasks such as those found in teleoperation, virtual reality, or joystick-based computer access, require the generation of an intermediate electrical signal which is transmitted to the controlled subsystem (robot arm, virtual environment, or a cursor in a computer screen). When human movements are distorted, for instance, by tremor, performance can be improved by digitally filtering the intermediate signal before it reaches the controlled device. This paper introduces a novel tremor filtering framework in which digital equalizers are optimally designed through pursuit tracking task experiments. Due to inherent properties of the man-machine system, the design of tremor suppression equalizers presents two serious problems: 1) performance criteria leading to optimizations that minimize mean-squared error are not efficient for tremor elimination and 2) movement signals show ill-conditioned autocorrelation matrices, which often result in useless or unstable solutions. To address these problems, a new performance indicator in the context of tremor is introduced, and the optimal equalizer according to this new criterion is developed. Ill-conditioning of the autocorrelation matrix is overcome using a novel method which we call pulled-optimization. Experiments performed with artificially induced vibrations and a subject with Parkinson's disease show significant improvement in performance. Additional results, along with MATLAB source code of the algorithms, and a customizable demo for PC joysticks, are available on the Internet at http:¿tremor-suppression.com.

Experimental study of filter cake formation on different filter media

International Nuclear Information System (INIS)

Saleem, M.

2009-01-01

Removal of particulate matter from gases generated in the process industry is important for product recovery as well as emission control. Dynamics of filtration plant depend on operating conditions. The models, that predict filter plant behaviour, involve empirical resistance parameters which are usually derived from limited experimental data and are characteristics of the filter media and filter cake (dust deposited on filter medium). Filter cake characteristics are affected by the nature of filter media, process parameters and mode of filter regeneration. Removal of dust particles from air is studied in a pilot scale jet pulsed bag filter facility resembling closely to the industrial filters. Limestone dust and ambient air are used in this study with two widely different filter media. All important parameters like pressure drop, gas flow rate, dust settling, are recorded continuously at 1s interval. The data is processed for estimation of the resistance parameters. The pressure drop rise on test filter media is compared. Results reveal that the surface of filter media has an influence on pressure drop rise (concave pressure drop rise). Similar effect is produced by partially jet pulsed filter surface. Filter behaviour is also simulated using estimated parameters and a simplified model and compared with the experimental results. Distribution of cake area load is therefore an important aspect of jet pulse cleaned bag filter modeling. Mean specific cake resistance remains nearly constant on thoroughly jet pulse cleaned membrane coated filter bags. However, the trend can not be confirmed without independent cake height and density measurements. Thus the results reveal the importance of independent measurements of cake resistance. (author)

MST Filterability Tests

Energy Technology Data Exchange (ETDEWEB)

Poirier, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Burket, P. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Duignan, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-03-12

The Savannah River Site (SRS) is currently treating radioactive liquid waste with the Actinide Removal Process (ARP) and the Modular Caustic Side Solvent Extraction Unit (MCU). The low filter flux through the ARP has limited the rate at which radioactive liquid waste can be treated. Recent filter flux has averaged approximately 5 gallons per minute (gpm). Salt Batch 6 has had a lower processing rate and required frequent filter cleaning. Savannah River Remediation (SRR) has a desire to understand the causes of the low filter flux and to increase ARP/MCU throughput. In addition, at the time the testing started, SRR was assessing the impact of replacing the 0.1 micron filter with a 0.5 micron filter. This report describes testing of MST filterability to investigate the impact of filter pore size and MST particle size on filter flux and testing of filter enhancers to attempt to increase filter flux. The authors constructed a laboratory-scale crossflow filter apparatus with two crossflow filters operating in parallel. One filter was a 0.1 micron Mott sintered SS filter and the other was a 0.5 micron Mott sintered SS filter. The authors also constructed a dead-end filtration apparatus to conduct screening tests with potential filter aids and body feeds, referred to as filter enhancers. The original baseline for ARP was 5.6 M sodium salt solution with a free hydroxide concentration of approximately 1.7 M.3 ARP has been operating with a sodium concentration of approximately 6.4 M and a free hydroxide concentration of approximately 2.5 M. SRNL conducted tests varying the concentration of sodium and free hydroxide to determine whether those changes had a significant effect on filter flux. The feed slurries for the MST filterability tests were composed of simple salts (NaOH, NaNO₂, and NaNO₃) and MST (0.2 – 4.8 g/L). The feed slurry for the filter enhancer tests contained simulated salt batch 6 supernate, MST, and filter enhancers.

Mechanical comparison of a polymer nanocomposite to a ceramic thin-film anti-reflective filter

International Nuclear Information System (INIS)

Druffel, Thad; Geng Kebin; Grulke, Eric

2006-01-01

Thin-film filters on optical components have been in use for decades and, for those industries utilizing a polymer substrate, the mismatch in mechanical behaviour has caused problems. Surface damage including scratches and cracks induces haze on the optical filter, reducing the transmission of the optical article. An in-mold anti-reflective (AR) filter incorporating 1/4-wavelength thin films based on a polymer nanocomposite is outlined here and compared with a traditional vacuum deposition AR coating. Nanoindentation and nanoscratch techniques are used to evaluate the mechanical properties of the thin films. Scanning electron microscopy (SEM) images of the resulting indentations and scratches are then compared to the force deflection curves to further explain the phenomena. The traditional coatings fractured by brittle mechanisms during testing, increasing the area of failure, whereas the polymer nanocomposite gave ductile failure with less surface damage

Mechanical comparison of a polymer nanocomposite to a ceramic thin-film anti-reflective filter.

Science.gov (United States)

Druffel, Thad; Geng, Kebin; Grulke, Eric

2006-07-28

Thin-film filters on optical components have been in use for decades and, for those industries utilizing a polymer substrate, the mismatch in mechanical behaviour has caused problems. Surface damage including scratches and cracks induces haze on the optical filter, reducing the transmission of the optical article. An in-mold anti-reflective (AR) filter incorporating 1/4-wavelength thin films based on a polymer nanocomposite is outlined here and compared with a traditional vacuum deposition AR coating. Nanoindentation and nanoscratch techniques are used to evaluate the mechanical properties of the thin films. Scanning electron microscopy (SEM) images of the resulting indentations and scratches are then compared to the force deflection curves to further explain the phenomena. The traditional coatings fractured by brittle mechanisms during testing, increasing the area of failure, whereas the polymer nanocomposite gave ductile failure with less surface damage.

Application of artificial neural networks for versatile preprocessing of electrocardiogram recordings.

Science.gov (United States)

Mateo, J; Rieta, J J

2012-02-01

The electrocardiogram (ECG) is the most widely used method for diagnosis of heart diseases, where a good quality of recordings allows the proper interpretation and identification of physiological and pathological phenomena. However, ECG recordings often have interference from noises including thermal, muscle, baseline and powerline noises. These signals severely limit ECG recording utility and, hence, have to be removed. To deal with this problem, the present paper proposes an artificial neural network (ANN) as a filter to remove all kinds of noise in just one step. The method is based on a growing ANN which optimizes both the number of nodes in the hidden layer and the coefficient matrices, which are optimized by means of the Widrow-Hoff delta algorithm. The ANN has been trained with a database comprising all kinds of noise, both from synthesized and real ECG recordings, in order to handle any noise signal present in the ECG. The proposed system improves results yielded by conventional techniques of ECG filtering, such as FIR-based systems, adaptive filtering and wavelet filtering. Therefore, the algorithm could serve as an effective framework to substantially reduce noise in ECG recordings. In addition, the resulting ECG signal distortion is notably more reduced in comparison with conventional methodologies. In summary, the current contribution introduces a new method which is able to suppress all ECG interference signals in only one step with low ECG distortion and a high noise reduction.

High-Q Tl2CaBa2Cu2O8 high-Tc superconducting quasi-optical millimeter-wave bandpass filters working at 77 K

International Nuclear Information System (INIS)

Zhang, D.; Fetterman, H.R.

1994-01-01

Tl 2 CaBa 2 Cu 2 O 8 high-temperature superconducting thin films with T c 's of over 100 K on LaAlO 3 substrates were used to fabricate quasi-optical millimeter-wave bandpass filters. Q-factors of over 400 were achieved, at liquid nitrogen temperatures from these filters at W-band frequencies (75--110 GHz)

Effects of bamboo substrate and supplemental feeding on growth and production of hybrid red tilapia fingerlings (Oreochromis mossambicusxOrechromis niloticus)

NARCIS (Netherlands)

Keshavanath, P.; Gangadhar, B.; Ramesh, T.J.; Dam, van A.A.; Beveridge, M.C.M.; Verdegem, M.C.J.

2004-01-01

Periphyton growing on artificial substrates can increase the production of herbivorous fish in aquaculture ponds. Periphyton may be an alternative or a complement for supplemental feed in fingerling production. Growth and production of hybrid red tilapia (Oreochromis mossambicus x Oreochromis

Electrochemical corrosion of cermet coatings in artificial marine water

International Nuclear Information System (INIS)

Cabot, P.L.; Fernandez, J.; Guilemany, J.M.

1998-01-01

The electrochemical corrosion of different WC+12Co coatings sprayed on 34CrMo4 (UNS-G41350) steel by the high velocity oxygen fuel technique has been studied by corrosion potential and impedance measurements considering previous SEM observations and EDX microanalysis. The experiments were conducted in artificial marine water at 20 C and the impedance spectra were obtained at the corresponding corrosion potentials for the substrate, coating and substrate-coating systems. The impedance diagrams indicated that the electrochemical corrosion of the steel-coating systems is controlled by oxygen diffusion through a porous film of corrosion products, as in the case of the shot-blasted steel. In contrast, the corrosion of the coating appeared to be controlled by diffusion of oxygen through the electrolyte. The impedance diagrams obtained for the steel-coating systems depended on the porosities of the cermet coatings, thus being an useful procedure to characterize metals coated by cermets. (orig.)

The productive cellulase binding capacity of cellulosic substrates.

Science.gov (United States)

Karuna, Nardrapee; Jeoh, Tina

2017-03-01

Cellulosic biomass is the most promising feedstock for renewable biofuel production; however, the mechanisms of the heterogeneous cellulose saccharification reaction are still unsolved. As cellulases need to bind isolated molecules of cellulose at the surface of insoluble cellulose fibrils or larger aggregated cellulose structures in order to hydrolyze glycosidic bonds, the "accessibility of cellulose to cellulases" is considered to be a reaction limiting property of cellulose. We have defined the accessibility of cellulose to cellulases as the productive binding capacity of cellulose, that is, the concentration of productive binding sites on cellulose that are accessible for binding and hydrolysis by cellulases. Productive cellulase binding to cellulose results in hydrolysis and can be quantified by measuring hydrolysis rates. In this study, we measured the productive Trichoderma reesei Cel7A (TrCel7A) binding capacity of five cellulosic substrates from different sources and processing histories. Swollen filter paper and bacterial cellulose had higher productive binding capacities of ∼6 µmol/g while filter paper, microcrystalline cellulose, and algal cellulose had lower productive binding capacities of ∼3 µmol/g. Swelling and regenerating filter paper using phosphoric acid increased the initial accessibility of the reducing ends to TrCel7A from 4 to 6 µmol/g. Moreover, this increase in initial productive binding capacity accounted in large part for the difference in the overall digestibility between filter paper and swollen filter paper. We further demonstrated that an understanding of how the productive binding capacity declines over the course of the hydrolysis reaction has the potential to predict overall saccharification time courses. Biotechnol. Bioeng. 2017;114: 533-542. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Numerical study of canister filters with alternatives filter cap configurations

Science.gov (United States)

Mohammed, A. N.; Daud, A. R.; Abdullah, K.; Seri, S. M.; Razali, M. A.; Hushim, M. F.; Khalid, A.

2017-09-01

Air filtration system and filter play an important role in getting a good quality air into turbo machinery such as gas turbine. The filtration system and filter has improved the quality of air and protect the gas turbine part from contaminants which could bring damage. During separation of contaminants from the air, pressure drop cannot be avoided but it can be minimized thus helps to reduce the intake losses of the engine [1]. This study is focused on the configuration of the filter in order to obtain the minimal pressure drop along the filter. The configuration used is the basic filter geometry provided by Salutary Avenue Manufacturing Sdn Bhd. and two modified canister filter cap which is designed based on the basic filter model. The geometries of the filter are generated by using SOLIDWORKS software and Computational Fluid Dynamics (CFD) software is used to analyse and simulates the flow through the filter. In this study, the parameters of the inlet velocity are 0.032 m/s, 0.063 m/s, 0.094 m/s and 0.126 m/s. The total pressure drop produce by basic, modified filter 1 and 2 is 292.3 Pa, 251.11 Pa and 274.7 Pa. The pressure drop reduction for the modified filter 1 is 41.19 Pa and 14.1% lower compared to basic filter and the pressure drop reduction for modified filter 2 is 17.6 Pa and 6.02% lower compared to the basic filter. The pressure drops for the basic filter are slightly different with the Salutary Avenue filter due to limited data and experiment details. CFD software are very reliable in running a simulation rather than produces the prototypes and conduct the experiment thus reducing overall time and cost in this study.

A compact, higher order, high temperature superconductor microstrip bandpass filter on a two-inch lanthanum aluminate substrate for personal communication service applications

International Nuclear Information System (INIS)

Pal, Srikanta; Stevens, Chris; Edwards, David

2005-01-01

A practical design methodology for a compact parallel-coupled microstrip bandpass filter structure with steep attenuation is introduced using a computer-aided full wave electromagnetic simulation based on the method of moments. The structure consists of an array of fully aligned half-wavelength spiral meander line resonators. Aimed at application in the front-end receiver of digital cellular communication service, a 12-pole high temperature superconductor filter with 2.27% fractional bandwidth at 883.0 MHz was designed. The filter is fabricated using thallium-barium-calcium-copper oxide (TBCCO) thin films on a two-inch lanthanum aluminate (LaAlO 3 ) wafer. The S-parameter measurements show a good agreement with the simulated results. At 70 K, the 12-pole filter shows less than 0.4 dB insertion loss, 0.3 dB passband ripple, better than 12 dB return loss. The out of band rejection at 3 MHz below the passband edges is more than 60.0 dB. In order to estimate the power handling capability of the filter, the third-order intermodulation distortion was measured. A sensitivity analysis for the observed frequency shift in the filter is reported. Also from this analysis an approach for using the same design in 0.5% FBW applications is discussed

Inverse Problem of Air Filtration of Nanoparticles: Optimal Quality Factors of Fibrous Filters

Directory of Open Access Journals (Sweden)

Dahua Shou

2015-01-01

Full Text Available Application of nanofibers has become an emerging approach to enhance filtration efficiency, but questions arise about the decrease in Quality factor (QF for certain particles due to the rapidly increasing pressure drop. In this paper, we theoretically investigate the QF of dual-layer filters for filtration of monodisperse and polydisperse nanoparticles. The inverse problem of air filtration, as defined in this work, consists in determining the optimal construction of the two-layer fibrous filter with the maximum QF. In comparison to a single-layer substrate, improved QF values for dual-layer filters are found when a second layer with proper structural parameters is added. The influences of solidity, fiber diameter, filter thickness, face velocity, and particle size on the optimization of QF are studied. The maximum QF values for realistic polydisperse particles with a lognormal size distribution are also found. Furthermore, we propose a modified QF (MQF accounting for the effects of energy cost and flow velocity, which are significant in certain operations. The optimal MQF of the dual-layer filter is found to be over twice that of the first layer. This work provides a quick tool for designing and optimizing fibrous structures with better performance for the air filtration of specific nanoparticles.

ALGAE PROLIFERATION ON SUBSTRATES IMMERSED IN BIOLOGICALLY TREATED SEWAGE

Directory of Open Access Journals (Sweden)

Tomasz Garbowski

2017-01-01

Full Text Available Due fast biomass production, high affinity for N and P and possibilities to CO2 sequestration microalgae are currently in the spotlight, especially in renewable energy technologies sector. The majority of studies focus their attention on microalgae cultivation with respect to biomass production. Fuel produced from algal biomass can contribute to reducing consumption of conventional fossil fuels and be a remedy for a rising energy crisis and global warming induced by air pollution. Some authors opt for possibilities of using sewage as a nutrient medium in algae cultivation. Other scientists go one step further and present concepts to introduce microalgal systems as an integral part of wastewater treatment plants. High costs of different microalgal harvesting methods caused introduction of the idea of algae immobilization in a form of periphyton on artificial substrates. In the present study the attention has focused on possibilities of using waste materials as substrates to proliferation of periphyton in biologically treated sewage that contained certain amounts of nitrogen and phosphorus.

Optimization of the selection process of the co-substrates for chicken manure fermentation using neural modeling

Directory of Open Access Journals (Sweden)

Lewicki Andrzej

2016-01-01

Full Text Available Intense development of research equipment leads directly to increasing cognitive abilities. However, along with the raising amount of data generated, the development of the techniques allowing the analysis is also essential. Currently, one of the most dynamically developing branch of computer science and mathematics are the Artificial Neural Networks (ANN. Their main advantage is very high ability to solve the regression and approximation issues. This paper presents the possibility of application of artificial intelligence methods to optimize the selection of co-substrates intended for methane fermentation of chicken manure. 4-layer MLP network has proven to be the optimal structure modeling the obtained empirical data.

UV protection filters by dielectric multilayer thin films on Glass BK-7 and Infrasil 301

International Nuclear Information System (INIS)

Abdel-Aziz, M.M.; Azim, Osama A.; Abdel-Wahab, L.A.; Seddik, Mohamed M.

2006-01-01

The increasing use of Ultraviolet (UV) light in medicine, industrial environments, for cosmetic use, and even in consumer products necessitates that greater attention be paid to the potential hazards of this type of electromagnetic radiation. To avoid any adverse effects of exposure to this type of radiation, four suitable protection filters were produced to block three UV bands (UVA, UVB, and UVC). The design structure of the required dielectric multilayer filters was done by optical thin film technology using the absorbing property of UV radiation for the substrates and dielectric materials. The computer analyses of the multilayer filter formulas were prepared using Macleod Software for the production processes. The deposition technique was achieved on optical substrates (Glass BK-7 and Infrasil 301) by dielectric material combinations including Titanium dioxide (Ti 2 O 3 ), Hafnium dioxide (HfO 2 ), and Lima (mixture of oxides SiO 2 /Al 2 O 3 ); deposition being achieved using an electron beam gun. The output results of the theoretical and experimental transmittance values for spectral band from 200 nm to 800 nm were discussed in four processes. To analyze the suitability for use in 'real world' applications, the test pieces were subjected to the durability tests (adhesion, abrasion resistance, and humidity) according to Military Standard MIL-C-675C and MIL-C-48497A

UV protection filters by dielectric multilayer thin films on Glass BK-7 and Infrasil 301

Science.gov (United States)

Abdel-Aziz, M. M.; Azim, Osama A.; Abdel-Wahab, L. A.; Seddik, Mohamed M.

2006-10-01

The increasing use of Ultraviolet (UV) light in medicine, industrial environments, for cosmetic use, and even in consumer products necessitates that greater attention be paid to the potential hazards of this type of electromagnetic radiation. To avoid any adverse effects of exposure to this type of radiation, four suitable protection filters were produced to block three UV bands (UVA, UVB, and UVC). The design structure of the required dielectric multilayer filters was done by optical thin film technology using the absorbing property of UV radiation for the substrates and dielectric materials. The computer analyses of the multilayer filter formulas were prepared using Macleod Software for the production processes. The deposition technique was achieved on optical substrates (Glass BK-7 and Infrasil 301) by dielectric material combinations including Titanium dioxide (Ti 2O 3), Hafnium dioxide (HfO 2), and Lima (mixture of oxides SiO 2/Al 2O 3); deposition being achieved using an electron beam gun. The output results of the theoretical and experimental transmittance values for spectral band from 200 nm to 800 nm were discussed in four processes. To analyze the suitability for use in 'real world' applications, the test pieces were subjected to the durability tests (adhesion, abrasion resistance, and humidity) according to Military Standard MIL-C-675C and MIL-C-48497A.

A valley-filtering switch based on strained graphene.

Science.gov (United States)

Zhai, Feng; Ma, Yanling; Zhang, Ying-Tao

2011-09-28

We investigate valley-dependent transport through a graphene sheet modulated by both the substrate strain and the fringe field of two parallel ferromagnetic metal (FM) stripes. When the magnetizations of the two FM stripes are switched from the parallel to the antiparallel alignment, the total conductance, valley polarization and valley conductance excess change greatly over a wide range of Fermi energy, which results from the dependence of the valley-related transmission suppression on the polarity configuration of inhomogeneous magnetic fields. Thus the proposed structure exhibits the significant features of a valley-filtering switch and a magnetoresistance device.

A valley-filtering switch based on strained graphene

International Nuclear Information System (INIS)

Zhai Feng; Ma Yanling; Zhang Yingtao

2011-01-01

We investigate valley-dependent transport through a graphene sheet modulated by both the substrate strain and the fringe field of two parallel ferromagnetic metal (FM) stripes. When the magnetizations of the two FM stripes are switched from the parallel to the antiparallel alignment, the total conductance, valley polarization and valley conductance excess change greatly over a wide range of Fermi energy, which results from the dependence of the valley-related transmission suppression on the polarity configuration of inhomogeneous magnetic fields. Thus the proposed structure exhibits the significant features of a valley-filtering switch and a magnetoresistance device. (paper)

Functional paper-based SERS substrate for rapid and sensitive detection of Sudan dyes in herbal medicine

Science.gov (United States)

Wu, Mianmian; Li, Pan; Zhu, Qingxia; Wu, Meiran; Li, Hao; Lu, Feng

2018-05-01

There has been an increasing demand for rapid and sensitive techniques for the identification of Sudan compounds that emerged as the most often illegally added fat-soluble dyes in herbal medicine. In this report, we have designed and fabricated a functionalized filter paper consisting of gold nanorods (GNRs) and mono-6-thio-cyclodextrin (HS-β-CD) as a surface-enhanced Raman spectroscopy (SERS) substrate, in which the GNR provides sufficient SERS enhancement, and the HS-β-CD with strong chemical affinity toward GNR provides the inclusion compound to capture hydrophobic molecules. Moreover, the CD-GNR were uniformly assembled on filter paper cellulose through the electrostatic adsorption and hydrogen bond, so that the CD-GNR paper-based SERS substrate (CD-GNR-paper) demonstrated higher sensitivity for the determination of Sudan III (0.1 μM) and Sudan IV (0.5 μM) than GNRs paper-based SERS substrate (GNR-paper), with high stability after the storage in the open air for 90 days. Importantly, CD-GNR-paper can effectively collect the Sudan dyes from illegally adulterated onto samples of Resina Draconis with a simple operation, further open up new exciting opportunity for SERS detection of more compounds illegally added with high sensitivity and fast signal responses.

[Evaluation of drinking-water treatment by Lifestraw® and Ceramic-pot filters].

Science.gov (United States)

Pérez-Vidal, Andrea; Díaz-Gómez, Jaime; Salamanca-Rojas, Karen L; Rojas-Torres, Leidy Y

2016-04-01

Objective To evaluate under laboratory conditions, the removal efficiency of turbidity and E. coli of two household water filters: LifeStraw® family (MF) and ceramic pot filter (CPF). Methods The two systems were operated over 6 months using two identical control units per system, treating 7.5 L/d of a synthetic substrate used as raw water. The turbidity of the substrate was adjusted with Kaolinite and the E. coli concentration, with a replica of the ATCC 95922 strain. The differences of effluent quality of the systems, in terms of turbidity and E. coli, were evaluated with Analysis of Variance (ANOVA). Operative and maintenance aspects, that could limit or enhance the use of the systems, were also considered in the evaluation. Results The water synthetic substrate quality had an average of 32.2 ± 2.8 NTU for turbidity and 3,9x105 UFC/100 mL for E. coli. Both systems reduce the turbidity to values below 2 NTU with an inactivation of 100 % of E. coli. Statistical differences were found between the systems in terms of turbidity removal, MF being more efficient than the CPF (99,2 ± 0.4 % and 97.6 % ± 1.14, respectively). Conclusions Both systems are suitable for household water supply treatment, acheiving the water quality standards established by Colombian regulations. The MF was more efficient for suspended solids removal and filtration rate, but when economic, operative, and maintenance aspects along with social acceptability and lifespan are considered, the CPF seems more suitable, especially in rural areas.

Wide Bandpass and Narrow Bandstop Microstrip Filters based on Hilbert fractal geometry: design and simulation results.

Directory of Open Access Journals (Sweden)

Yaqeen S Mezaal

Full Text Available This paper presents new Wide Bandpass Filter (WBPF and Narrow Bandstop Filter (NBSF incorporating two microstrip resonators, each resonator is based on 2nd iteration of Hilbert fractal geometry. The type of filter as pass or reject band has been adjusted by coupling gap parameter (d between Hilbert resonators using a substrate with a dielectric constant of 10.8 and a thickness of 1.27 mm. Numerical simulation results as well as a parametric study of d parameter on filter type and frequency responses are presented and studied. WBPF has designed at resonant frequencies of 2 and 2.2 GHz with a bandwidth of 0.52 GHz, -28 dB return loss and -0.125 dB insertion loss while NBSF has designed for electrical specifications of 2.37 GHz center frequency, 20 MHz rejection bandwidth, -0.1873 dB return loss and 13.746 dB insertion loss. The proposed technique offers a new alternative to construct low-cost high-performance filter devices, suitable for a wide range of wireless communication systems.

Performance of biomorphic Silicon Carbide as particulate filter in diesel boilers.

Science.gov (United States)

Orihuela, M Pilar; Gómez-Martín, Aurora; Becerra, José A; Chacartegui, Ricardo; Ramírez-Rico, Joaquín

2017-12-01

Biomorphic Silicon Carbide (bioSiC) is a novel porous ceramic material with excellent mechanical and thermal properties. Previous studies have demonstrated that it may be a good candidate for its use as particle filter media of exhaust gases at medium or high temperature. In order to determine the filtration efficiency of biomorphic Silicon Carbide, and its adequacy as substrate for diesel particulate filters, different bioSiC-samples have been tested in the flue gases of a diesel boiler. For this purpose, an experimental facility to extract a fraction of the boiler exhaust flow and filter it under controlled conditions has been designed and built. Several filter samples with different microstructures, obtained from different precursors, have been tested in this bench. The experimental campaign was focused on the measurement of the number and size of particles before and after placing the samples. Results show that the initial efficiency of filters made from natural precursors is severely determined by the cutting direction and associated microstructure. In biomorphic Silicon Carbide derived from radially cut wood, the initial efficiency of the filter is higher than 95%. Nevertheless, when the cut of the wood is axial, the efficiency depends on the pore size and the permeability, reaching in some cases values in the range 70-90%. In this case, the presence of macropores in some of the samples reduces their efficiency as particle traps. In continuous operation, the accumulation of particles within the porous media leads to the formation of a soot cake, which improves the efficiency except in the case when extra-large pores exist. For all the samples, after a few operation cycles, capture efficiency was higher than 95%. These experimental results show the potential for developing filters for diesel boilers based on biomorphic Silicon Carbide. Copyright © 2017 Elsevier Ltd. All rights reserved.

Controlling flow conditions of test filters in iodine filters

International Nuclear Information System (INIS)

Holmberg, R.; Laine, J.

1979-03-01

Several different iodine filter and test filter designs and experience gained from their operation are presented. For the flow experiments, an iodine filter system equipped with flow regulating and measuring devices was built. In the experiments the influence of the packing method of the iodine sorption material and the influence of the flow regulating and measuring divices upon the flow conditions in the test filters was studied. On the basis of the experiments it has been shown that the flows through the test filters always can be adjusted to a correct value if there only is a high enough pressure difference available across the test filter ducting. As a result of the research, several different methods are presented with which the flows through the test filters in both operating and future iodine sorption system can easily be measured and adjusted to their correct values. (author)

Different Heavy Metal Accumulation Strategies of Epilithic Lichens Colonising Artificial Post-Smelting Wastes.

Science.gov (United States)

Rola, Kaja; Osyczka, Piotr; Kafel, Alina

2016-02-01

Lichens appear to be essential and effective colonisers of bare substrates including the extremely contaminated wastes of slag dumps. This study examines the metal accumulation capacity of epilithic lichens growing directly on the surface of artificial slag sinters. Four species representing different growth forms, i.e., crustose Candelariella aurella, Lecanora muralis, and Lecidea fuscoatra and fruticose Stereocaulon nanodes, were selected to evaluate the relationships between zinc, lead, cadmium, and nickel contents in their thalli and host substrates. Bioaccumulation factors of examined crustose lichens showed their propensity to hyperaccumulate heavy metals. Contrarily, concentrations of metals in fruticose thalli of S. nanodes were, as a rule, lower than in the corresponding substrates. This indicates that the growth form of thalli and degree of thallus adhesion to the substrate has a significant impact on metal concentrations in lichens colonising post-smelting wastes. Nonlinear regression models described by power functions show that at greater levels of Pb concentration in the substrate, the ability of C. aurella, L. muralis and L. fuscoatra to accumulate the metal experiences a relative decrease, whereas hyperbolic function describes a similar trend in relation to Ni content in S. nanodes. This phenomenon may be an important attribute of lichens that facilitates their colonisation of the surface of slag wastes.

HTS dual-band bandpass filters using stub-loaded hair-pin resonators for mobile communication systems

Energy Technology Data Exchange (ETDEWEB)

Sekiya, N., E-mail: nsekiya@yamanashi.ac.jp; Sugiyama, S.

2014-09-15

Highlights: • We have developed a HTS five-pole dual-band bandpass filter using stub-loaded hair-pin resonators. • The proposed dual-band BPF can independently control of the center frequency. • Flexibly adjustment of the bandwidth can be achieved by the H-shaped waveguide. • The proposed BPF is evaluated by simulation and measurement with good agreement. - Abstract: A HTS dual-band bandpass filter is developed to obtain sharp-cut off characteristics for mobile communication systems. The filter is composed of five stub-loaded hair-pin resonators with H-shaped waveguides between them. The main advantage of the proposed filter is to allow independent control of the center frequency of the first and second bands. The bandwidths can be flexibly adjusted using the H-shaped waveguide. An electromagnetic simulator was used to design and analyze the filter, which have a 3.5-GHz center frequency and a 70-MHz (2%) bandwidth for the first band and a 5.0-GHz center frequency and a 100-MHz (2%) bandwidth for the second band. The filter was fabricated using YBa{sub 2}Cu{sub 3}O{sub y} thin film on an Al{sub 2}O{sub 3} substrate. Ground plane was fabricated using Au thin film. The measured frequency responses of the filter tally well with the simulated ones.

Estimating the Permittivity of Rogers 4003C Substrate at Low Frequencies for Application in a Superdirective First-Order Probe for SNF Measurements

DEFF Research Database (Denmark)

Kim, Oleksiy S.

2016-01-01

The bulk permittivity of Rogers 4003C substrate is estimated in the lower UHF frequency band by comparing the simulated and measured return loss for a bandpass filter based on a coplanar waveguide and a capacitively loaded loop. The obtained value, which deviates from that specified by Rogers at ...... GHz, is subsequently utilized for accurate design of a new light-weight superdirective first-order probe for spherical near-field (SNF) antenna measurements at low frequencies.......The bulk permittivity of Rogers 4003C substrate is estimated in the lower UHF frequency band by comparing the simulated and measured return loss for a bandpass filter based on a coplanar waveguide and a capacitively loaded loop. The obtained value, which deviates from that specified by Rogers at 10...

The Rao-Blackwellized Particle Filter: A Filter Bank Implementation

Directory of Open Access Journals (Sweden)

Karlsson Rickard

2010-01-01

Full Text Available For computational efficiency, it is important to utilize model structure in particle filtering. One of the most important cases occurs when there exists a linear Gaussian substructure, which can be efficiently handled by Kalman filters. This is the standard formulation of the Rao-Blackwellized particle filter (RBPF. This contribution suggests an alternative formulation of this well-known result that facilitates reuse of standard filtering components and which is also suitable for object-oriented programming. Our RBPF formulation can be seen as a Kalman filter bank with stochastic branching and pruning.

Convergent Filter Bases

Directory of Open Access Journals (Sweden)

Coghetto Roland

2015-09-01

Full Text Available We are inspired by the work of Henri Cartan [16], Bourbaki [10] (TG. I Filtres and Claude Wagschal [34]. We define the base of filter, image filter, convergent filter bases, limit filter and the filter base of tails (fr: filtre des sections.

A new design of a miniature filter on microstrip resonators with an interdigital structure of conductors

Science.gov (United States)

Belyaev, B. A.; Serzhantov, A. M.; Bal'va, Ya. F.; Leksikov, An. A.; Galeev, R. G.

2015-05-01

A microstrip bandpass filter of new design based on original resonators with an interdigital structure of conductors has been studied. The proposed filters of third to sixth order are distinguished for their high frequency-selective properties and much smaller size than analogs. It is established that a broad stop band, extending up to a sixfold central bandpass frequency, is determined by low unloaded Q of higher resonance mode and weak coupling of resonators in the pass band. It is shown for the first time that, as the spacing of interdigital stripe conductors decreases, the Q of higher resonance mode monotonically drops, while the Q value for the first operating mode remains high. A prototype fourth-order filter with a central frequency of 0.9 GHz manufactured on a ceramic substrate with dielectric permittivity ɛ = 80 has microstrip topology dimensions of 9.5 × 4.6 × 1 mm3. The electrodynamic 3D model simulations of the filter characteristics agree well with the results of measurements.

[Artificial organs].

Science.gov (United States)

Raguin, Thibaut; Dupret-Bories, Agnès; Debry, Christian

2017-01-01

Research has been fighting against organ failure and shortage of donations by supplying artificial organs for many years. With the raise of new technologies, tissue engineering and regenerative medicine, many organs can benefit of an artificial equivalent: thanks to retinal implants some blind people can visualize stimuli, an artificial heart can be proposed in case of cardiac failure while awaiting for a heart transplant, artificial larynx enables laryngectomy patients to an almost normal life, while the diabetic can get a glycemic self-regulation controlled by smartphones with an artificial device. Dialysis devices become portable, as well as the oxygenation systems for terminal respiratory failure. Bright prospects are being explored or might emerge in a near future. However, the retrospective assessment of putative side effects is not yet sufficient. Finally, the cost of these new devices is significant even if the advent of three dimensional printers may reduce it. © 2017 médecine/sciences – Inserm.

The in-situ testing of high efficiency particulate filters in the CEGB south eastern region nuclear power stations

International Nuclear Information System (INIS)

Powell, A.W.; Wilkinson, B.A.

1977-01-01

High efficiency air filters are installed in the CEGB's Nuclear Power Stations to prevent discharge of radioactive material to the environment should the ventilation air become contaminated. The Board has determined that these filter units should be tested in-situ to ensure that the stringent design specifications are met. This paper describes the rig work comparing the British Standard method using sodium chloride aerosol with other test methods, such as Dioctyl Phthalate, naturally occurring dust aerosols and artificially produced condensation nuclei. This work led to the development of an in-situ test method using condensation nuclei and a Pollak-Nolan nucleus counter. The advantages and disadvantages of this method over other methods for in-situ testing is discussed. The test method has been used in the South Eastern Region for several years and considerable experience has been gained in its use on a wide variety of filter systems. The method adopted for each system is detailed including the injection, sampling and interpretation of the results obtained. Numerous faults and difficulties have been highlighted from the design, installation and filter changing aspects

Application of DFT Filter Banks and Cosine Modulated Filter Banks in Filtering

Science.gov (United States)

Lin, Yuan-Pei; Vaidyanathan, P. P.

1994-01-01

None given. This is a proposal for a paper to be presented at APCCAS '94 in Taipei, Taiwan. (From outline): This work is organized as follows: Sec. II is devoted to the construction of the new 2m channel under-decimated DFT filter bank. Implementation and complexity of this DFT filter bank are discussed therein. IN a similar manner, the new 2m channel cosine modulated filter bank is discussed in Sec. III. Design examples are given in Sec. IV.

System on Package (SoP) Millimeter Wave Filters for 5G Applications

KAUST Repository

Showail, Jameel

2018-05-01

Bandpass filters are an essential component of wireless communication systems that only transmits frequencies corresponding to the communication band and rejects all other frequencies. As the deployment of 5G draws nearer, first deployments are expected in 2020 [1], the need for viable filters at the new frequency bands becomes more imminent. Size and performance are two critical considerations for a filter that will be used in emerging mobile communication applications. The high frequency of 5G communication, 28 GHz as opposed to sub 6 GHz for nearly all previous communication protocols, means that previously utilized lumped component based solutions cannot be implemented since they are ill-suited for mm-wave applications. The focus of this work is the miniaturization of a high-performance filter. The Substrate Integrated Waveguide (SIW) is a high performance and promising structure and Low Temperature Co-Fired Ceramic (LTCC) is a high-performance material that both can operate at higher frequencies than the technologies used for previous telecommunication generations. To miniaturize the structure, a compact folded four-cavity SIW filter is designed, implemented and tested. The feeding structure is integrated into the filter to exploit the System on Package (SoP) attributes of LTCC and further reduce the total area of the filter individually and holistically when looking at the final integrated system. Two unique three dimensional (3D) integrated SoP LTCC two-stage SIW single cavity filters and one unique four-cavity filter all with embedded planar resonators are designed, fabricated and tested. The embedded resonators create a two-stage effect in a single cavity filter. The better single cavity design provides a 15% fractional bandwidth at a center frequency of 28.12 GHz, and with an insertion loss of -0.53 dB. The fabricated four-cavity filter has a 3-dB bandwidth of .98GHz centered at 27.465 GHz, and with an insertion loss of -2.66 dB. The designs presented

Guided-mode resonant filters and reflectors: Principles, design, and fabrication

Science.gov (United States)

Niraula, Manoj

In this dissertation, we overview the operational principles of these resonant periodic structures, discuss the methods of their design and fabrication, and propose and demonstrate novel functionalities for spatial and spectral filtering, and unpolarized wideband reflection. Fashioned with materially sparse gratings, these optical devices are easy to fabricate and integration friendly compared to their traditional multi-layer counterparts making their research and development critical for practical applications. We study, theoretically, modal properties and parametric dependence of resonant periodic bandpass filters operating in the mid- and near-infrared spectral domains. We investigate three different device architectures consisting of single, double, and triple layers based on all-transparent dielectric and semiconductor thin films. We present three modal coupling configurations forming complex mixtures of two or three distinct leaky modes coupling at different evanescent diffraction orders. Our modal analysis demonstrates key attributes of subwavelength periodic thin-film structures in multiple-modal blending to achieve desired transmission spectra. We provide the first experimental demonstration of high-efficiency and narrow-linewidth resonant bandpass filter applying a single patterned silicon layer on a quartz substrate. Its performance corresponds to bandpass filters requiring 15 traditional Si/SiO2 thin-film layers. The feasibility of sparse narrowband, high-efficiency bandpass filters with extremely wide, flat, and low sidebands is thereby demonstrated. The proposed technology is integration-friendly and opens doors for further development in various disciplines and spectral regions where thin-film solutions are traditionally applied. We demonstrate concurrent spatial and spectral filtering as a new outstanding attribute of resonant periodic devices. This functionality is enabled by a unique, near-complete, reflection state that is discrete in both

Flexible photonic-crystal Fano filters based on transferred semiconductor nanomembranes

Energy Technology Data Exchange (ETDEWEB)

Zhou Weidong; Yang Hongjun; Qiang Zexuan; Chen Li; Yang Weiquan; Chuwongin, Santhad; Zhao Deyin [Department of Electrical Engineering, NanoFAB Center, University of Texas at Arlington, TX 76019 (United States); Ma Zhenqiang; Qin Guoxuan; Pang Huiqing, E-mail: wzhou@uta.ed, E-mail: mazq@engr.wisc.ed [Department of Electrical and Computer Engineering, University of Wisconsin-Madison, WI 53706 (United States)

2009-12-07

Crystalline semiconductor nanomembranes (NMs), which are transferable, stackable, bondable and manufacturable, offer unprecedented opportunities for unique and novel device applications. We report and review here nanophotonic devices based on stacked semiconductor NMs that were built on Si, glass and flexible PET substrates. Photonic-crystal Fano resonance based surface-normal optical filters and broadband reflectors have been demonstrated with unique angle and polarization properties. Such a low temperature NM stacking process can lead to a paradigm shift on silicon photonic integration and inorganic flexible photonics.

Artificial nacre-like papers based on noncovalent functionalized boron nitride nanosheets with excellent mechanical and thermally conductive properties

Science.gov (United States)

Zeng, Xiaoliang; Ye, Lei; Yu, Shuhui; Li, Hao; Sun, Rong; Xu, Jianbin; Wong, Ching-Ping

2015-04-01

Inspired by the nano/microscale hierarchical structure and the precise inorganic/organic interface of natural nacre, we fabricated artificial nacre-like papers based on noncovalent functionalized boron nitride nanosheets (NF-BNNSs) and poly(vinyl alcohol) (PVA) via a vacuum-assisted self-assembly technique. The artificial nacre-like papers exhibit excellent tensile strength (125.2 MPa), on a par with that of the natural nacre, and moreover display a 30% higher toughness (2.37 MJ m-3) than that of the natural nacre. These excellent mechanical properties result from an ordered `brick-and-mortar' arrangement of NF-BNNSs and PVA, in which the long-chain PVA molecules act as the bridge to link NF-BNNSs via hydrogen bonds. The resulting papers also render high thermal conductivity (6.9 W m-1 K-1), and reveal their superiority as flexible substrates to support light-emitting-diode chips. The combined mechanical and thermal properties make the materials highly desirable as flexible substrates for next-generation commercial portable electronics.Inspired by the nano/microscale hierarchical structure and the precise inorganic/organic interface of natural nacre, we fabricated artificial nacre-like papers based on noncovalent functionalized boron nitride nanosheets (NF-BNNSs) and poly(vinyl alcohol) (PVA) via a vacuum-assisted self-assembly technique. The artificial nacre-like papers exhibit excellent tensile strength (125.2 MPa), on a par with that of the natural nacre, and moreover display a 30% higher toughness (2.37 MJ m-3) than that of the natural nacre. These excellent mechanical properties result from an ordered `brick-and-mortar' arrangement of NF-BNNSs and PVA, in which the long-chain PVA molecules act as the bridge to link NF-BNNSs via hydrogen bonds. The resulting papers also render high thermal conductivity (6.9 W m-1 K-1), and reveal their superiority as flexible substrates to support light-emitting-diode chips. The combined mechanical and thermal properties make

A Study of Parallel Operation of an active Filter and passive Filters

DEFF Research Database (Denmark)

Chen, Zhe; Blaabjerg, Frede; Pedersen, John Kim

2002-01-01

This paper reports investigations of the parallel operations of a current controlled active filter and passive filters in a system with current harmonic sources. The task of reactive power and harmonic compensation is shared by the active filter and passive filters. The passive filters are used...... arrangements of the active and passive filters can operate relatively independently, also the compensation flexibility of the active filter can be fully exploited, such as one active filter for several harmonic sources.The simulation studies on various systems have been performed to evaluate the effectiveness...... of the systems. The results show that the power factor is corrected by the passive filters, harmonics are minimized by both active and passive filters and overloading of the filter system can be avoided....

Passive Power Filters

CERN Document Server

Künzi, R.

2015-06-15

Power converters require passive low-pass filters which are capable of reducing voltage ripples effectively. In contrast to signal filters, the components of power filters must carry large currents or withstand large voltages, respectively. In this paper, three different suitable filter struc tures for d.c./d.c. power converters with inductive load are introduced. The formulas needed to calculate the filter components are derived step by step and practical examples are given. The behaviour of the three discussed filters is compared by means of the examples. P ractical aspects for the realization of power filters are also discussed.

Silver-Nanoparticle-Based Screen-Printing and Film Characterization of a Disposable, Dual-Band, Bandstop Filter on a Flexible Polyethylene Terephthalate Substrate

Directory of Open Access Journals (Sweden)

Kishor Kumar Adhikari

2015-01-01

Full Text Available This paper presents a silver-nanoparticle-based, screen-printed, high-performance, dual-band, bandstop filter (DBBSF on a flexible polyethylene terephthalate (PET substrate. Using screen-printing techniques to process a highly viscous silver printing ink, high-conductivity printed lines were implemented at a web transfer speed of 5 m/min. Characterized by X-ray diffraction (XRD, optical microscopy, atomic force microscopy (AFM, and scanning electron microscopy (SEM, the printed lines were shown to be characterized by smooth surfaces with a root mean square roughness of 7.986 nm; a significantly higher thickness (12.2 μm than the skin depth; and a high conductivity of 2×107 S/m. These excellent printed line characteristics enabled the implementation of a high-selectivity DBBSF using shunt-connected uniform impedance resonators (UIRs. Additionally, the inductive loading effect of T-shaped stubs on the UIRs, which were analyzed using S-parameters based on lumped parameter calculations, was used to improve the return losses of the geometrically optimized DBBSF. The measured minimum return loss and maximum insertion loss of 28.26 and 1.58 dB, respectively, at the central frequencies of 2.56 and 5.29 GHz of a protocol screen-printed DBBSF demonstrated the excellent performance of the material and its significant potential for use in future cost-effective, flexible WiMax and WLAN applications.

The Fate of Mengovirus on Fiberglass Filter of Air Handling Units.

Science.gov (United States)

Bandaly, Victor; Joubert, Aurélie; Le Cann, Pierre; Andres, Yves

2017-12-01

One of the most important topics that occupy public health problems is the air quality. That is the reason why mechanical ventilation and air handling units (AHU) were imposed by the different governments in the collective or individual buildings. Many buildings create an artificial climate using heating, ventilation, and air-conditioning systems. Among the existing aerosols in the indoor air, we can distinguish the bioaerosol with biological nature such as bacteria, viruses, and fungi. Respiratory viral infections are a major public health issue because they are usually highly infective. We spend about 90% of our time in closed environments such as homes, workplaces, or transport. Some studies have shown that AHU contribute to the spread and transport of viral particles within buildings. The aim of this work is to study the characterization of viral bioaerosols in indoor environments and to understand the fate of mengovirus eukaryote RNA virus on glass fiber filter F7 used in AHU. In this study, a set-up close to reality of AHU system was used. The mengovirus aerosolized was characterized and measured with the electrical low pressure impact and the scanner mobility particle size and detected with RT-qPCR. The results about quantification and the level of infectivity of mengovirus on the filter and in the biosampler showed that mengovirus can pass through the filter and remain infectious upstream and downstream the system. Regarding the virus infectivity on the filter under a constant air flow, mengovirus was remained infectious during 10 h after aerosolization.

Nutrient leaching from extensive green roofs with different substrate compositions: a laboratory study.

Science.gov (United States)

Zhang, Wei; Zhong, Xing; Che, Wu

2018-02-01

To investigate nutrient leaching from extensive green roofs, green roof platforms were established to investigate the effluent quantity and quality during artificial rainfall. When the influent volume reached three times the empty bed volume, for which the cumulative rainfall was around 300 mm, the effluent TP and COD concentrations of green roof platforms filled with peat soil did not tend to stabilize. For a long-term operation, the substrate depths had little significant influence on TN, TP and COD concentrations of the green roof effluents. A normalized cumulative emission process method was proposed to discuss the difference in various pollutant leaching processes. Obvious differences in the leaching process of different contaminants for green roof platforms filled with various substrates were observed. For the green roof filled with modified substrates, the nitrogen and phosphorus pollutant leaching rates were relatively high in the initial stage of green roof operation and the phosphorus leaching rate was higher than that of nitrogen. The green roof is a sink for TN, but not for TP and COD in this study. The outcomes are critical for the selection of green roof substrates and also contribute to green roof maintenance.

Particle Kalman Filtering: A Nonlinear Bayesian Framework for Ensemble Kalman Filters*

KAUST Repository

Hoteit, Ibrahim

2012-02-01

This paper investigates an approximation scheme of the optimal nonlinear Bayesian filter based on the Gaussian mixture representation of the state probability distribution function. The resulting filter is similar to the particle filter, but is different from it in that the standard weight-type correction in the particle filter is complemented by the Kalman-type correction with the associated covariance matrices in the Gaussian mixture. The authors show that this filter is an algorithm in between the Kalman filter and the particle filter, and therefore is referred to as the particle Kalman filter (PKF). In the PKF, the solution of a nonlinear filtering problem is expressed as the weighted average of an “ensemble of Kalman filters” operating in parallel. Running an ensemble of Kalman filters is, however, computationally prohibitive for realistic atmospheric and oceanic data assimilation problems. For this reason, the authors consider the construction of the PKF through an “ensemble” of ensemble Kalman filters (EnKFs) instead, and call the implementation the particle EnKF (PEnKF). It is shown that different types of the EnKFs can be considered as special cases of the PEnKF. Similar to the situation in the particle filter, the authors also introduce a resampling step to the PEnKF in order to reduce the risk of weights collapse and improve the performance of the filter. Numerical experiments with the strongly nonlinear Lorenz-96 model are presented and discussed.

Artificial Reef Effect in relation to Offshore Renewable Energy Conversion: State of the Art

Directory of Open Access Journals (Sweden)

Olivia Langhamer

2012-01-01

Full Text Available The rapid worldwide growth of offshore renewable energy production will provide marine organisms with new hard substrate for colonization, thus acting as artificial reefs. The artificial reef effect is important when constructing, for example, scour protections since it can generate an enhanced habitat. Specifically, artificial structures can create increased heterogeneity in the area important for species diversity and density. Offshore energy installations also have the positive side effect as they are a sanctuary area for trawled organisms. Higher survival of fish and bigger fish is an expected outcome that can contribute to a spillover to outer areas. One negative side effect is that invasive species can find new habitats in artificial reefs and thus influence the native habitats and their associated environment negatively. Different scour protections in offshore wind farms can create new habitats compensating for habitat loss by offshore energy installations. These created habitats differ from the lost habitat in species composition substantially. A positive reef effect is dependent on the nature and the location of the reef and the characteristics of the native populations. An increase in surface area of scour protections by using specially designed material can also support the reef effect and its productivity.

An improved ultra-wideband bandpass filter design using split ring resonator with coupled microstrip line

Science.gov (United States)

Umeshkumar, Dubey Suhmita; Kumar, Manish

2018-04-01

This paper incorporates an improved design of Ultra Wideband Bandpass filter by using split ring resonators (SRR) along with the coupled microstrip lines. The use of split ring resonators and shunt step impedance open circuit stub enhances the stability due to transmission zeroes at the ends. The designing of filter and simulation of parameters is carried out using Ansoft's HFSS 13.0 software on RT/Duroid 6002 as a substrate with dielectric constant of 2.94. The design utilizes a frequency band from 22GHz to 29GHz. This band is reserved for Automotive Radar system and sensors as per FCC specifications. The proposed design demonstrates insertion loss less than 0.6dB and return loss better than 12dB at mid frequency i.e. 24.4GHz. The reflection coefficient shows high stability of about 12.47dB at mid frequency. The fractional bandwidth of the proposed filter is about 28.7% and size of filter design is small due to thickness of 0.127mm.

Rectifier Filters

Directory of Open Access Journals (Sweden)

Y. A. Bladyko

2010-01-01

Full Text Available The paper contains definition of a smoothing factor which is suitable for any rectifier filter. The formulae of complex smoothing factors have been developed for simple and complex passive filters. The paper shows conditions for application of calculation formulae and filters. 

The creation of the artificial RING finger from the cross-brace zinc finger by α-helical region substitution

International Nuclear Information System (INIS)

Miyamoto, Kazuhide; Togiya, Kayo

2010-01-01

The creation of the artificial RING finger as ubiquitin-ligating enzyme (E3) has been demonstrated. In this study, by the α-helical region substitution between the EL5 RING finger and the Williams-Beuren syndrome transcription factor (WSTF) PHD finger, the artificial E3 (WSTF PHD R ING finger) was newly created. The experiments of the chemical modification of residues Cys and the circular dichroism spectra revealed that the WSTF PHD R ING finger binds two zinc atoms and adopts the zinc-dependent ordered-structure. In the substrate-independent ubiquitination assay, the WSTF PHD R ING finger functions as E3 and was poly- or mono-ubiquitinated. The present strategy is very simple and convenient, and consequently it might be widely applicable to the creation of various artificial E3 RING fingers with the specific ubiquitin-conjugating enzyme (E2)-binding capability.

Gold nanoparticles deposited on linker-free silicon substrate and embedded in aluminum Schottky contact.

Science.gov (United States)

Gorji, Mohammad Saleh; Razak, Khairunisak Abdul; Cheong, Kuan Yew

2013-10-15

Given the enormous importance of Au nanoparticles (NPs) deposition on Si substrates as the precursor for various applications, we present an alternative approach to deposit Au NPs on linker-free n- and p-type Si substrates. It is demonstrated that, all conditions being similar, there is a significant difference between densities of the deposited NPs on both substrates. The Zeta-potential and polarity of charges surrounding the hydroxylamine reduced seeded growth Au NPs, are determined by a Zetasizer. To investigate the surface properties of Si substrates, contact angle measurement is performed. Field-emission scanning electron microscope is then utilized to distinguish the NPs density on the substrates. Finally, Al/Si Schottky barrier diodes with embedded Au NPs are fabricated, and their structural and electrical characteristics are further evaluated using an energy-filtered transmission electron microscope and current-voltage measurements, respectively. The results reveal that the density of NPs is significantly higher on n-type Si substrate and consequently has more pronounced effects on the electrical characteristics of the diode. It is concluded that protonation of Si-OH group on Si surface in low pH is responsible for the immobilization of Au NPs, which eventually contributes to the lowering of barrier height and enhances the electrical characteristics. Copyright © 2013 Elsevier Inc. All rights reserved.

Retina-Inspired Filter.

Science.gov (United States)

Doutsi, Effrosyni; Fillatre, Lionel; Antonini, Marc; Gaulmin, Julien

2018-07-01

This paper introduces a novel filter, which is inspired by the human retina. The human retina consists of three different layers: the Outer Plexiform Layer (OPL), the inner plexiform layer, and the ganglionic layer. Our inspiration is the linear transform which takes place in the OPL and has been mathematically described by the neuroscientific model "virtual retina." This model is the cornerstone to derive the non-separable spatio-temporal OPL retina-inspired filter, briefly renamed retina-inspired filter, studied in this paper. This filter is connected to the dynamic behavior of the retina, which enables the retina to increase the sharpness of the visual stimulus during filtering before its transmission to the brain. We establish that this retina-inspired transform forms a group of spatio-temporal Weighted Difference of Gaussian (WDoG) filters when it is applied to a still image visible for a given time. We analyze the spatial frequency bandwidth of the retina-inspired filter with respect to time. It is shown that the WDoG spectrum varies from a lowpass filter to a bandpass filter. Therefore, while time increases, the retina-inspired filter enables to extract different kinds of information from the input image. Finally, we discuss the benefits of using the retina-inspired filter in image processing applications such as edge detection and compression.

In-plane deeply-etched optical MEMS notch filter with high-speed tunability

International Nuclear Information System (INIS)

Sabry, Yasser M; Eltagoury, Yomna M; Shebl, Ahmed; Khalil, Diaa; Soliman, Mostafa; Sadek, Mohamed

2015-01-01

Notch filters are used in spectroscopy, multi-photon microscopy, fluorescence instrumentation, optical sensors and other life science applications. One type of notch filter is based on a fiber-coupled Fabry–Pérot cavity, which is formed by a reflector (external mirror) facing a dielectric-coated end of an optical fiber. Tailoring this kind of optical filter for different applications is possible because the external mirror has fewer mechanical and optical constraints. In this paper we present optical modeling and implementation of a fiber-coupled Fabry–Pérot filter based on dielectric-coated optical fiber inserted into a micromachined fiber groove facing a metallized micromirror, which is driven by a high-speed MEMS actuator. The optical MEMS chip is fabricated using deep reactive ion etching (DRIE) technology on a silicon on insulator wafer, where the optical axis is parallel to the substrate (in-plane) and the optical/mechanical components are self-aligned by the photolithographic process. The DRIE etching depth is 150 μm, chosen to increase the micromirror optical throughput and improving the out-of-plane stiffness of the MEMS actuator. The MEMS actuator type is closing-gap, while its quality factor is almost doubled by slotting the fixed plate. A low-finesse Fabry–Pérot interferometer is formed by the metallized surface of the micromirror and a cleaved end of a standard single-mode fiber, for characterization of the MEMS actuator stroke and resonance frequency. The actuator achieves a travel distance of 800 nm at a resonance frequency of 89.9 kHz. The notch filter characteristics were measured using an optical spectrum analyzer, and the filter exhibits a free spectral range up to 100 nm and a notch rejection ratio up to 20 dB around a wavelength of 1300 nm. The presented device provides batch processing and low-cost production of the filter. (paper)

XII International Conference of the Italian Association on Artificial Intelligence

CERN Document Server

Semeraro, Giovanni; Vargiu, Eloisa; New Challenges in Distributed Information Filtering and Retrieval : DART 2011: Revised and Invited Papers

2013-01-01

This volume focuses on new challenges in distributed Information Filtering and Retrieval. It collects invited chapters and extended research contributions from the DART 2011 Workshop, held in Palermo (Italy), on September 2011, and co-located with the XII International Conference of the Italian Association on Artificial Intelligence. The main focus of DART was to discuss and compare suitable novel solutions based on intelligent techniques and applied to real-world applications. The chapters of this book present a comprehensive review of related works and state of the art. Authors, both practitioners and researchers, shared their results in several topics such as "Multi-Agent Systems", "Natural Language Processing", "Automatic Advertisement", "Customer Interaction Analytics", "Opinion Mining".

Braile vena cava filter and greenfield filter in terms of centralization.

Science.gov (United States)

de Godoy, José Maria Pereira; Menezes da Silva, Adinaldo A; Reis, Luis Fernando; Miquelin, Daniel; Torati, José Luis Simon

2013-01-01

The aim of this study was to evaluate complications experienced during implantation of the Braile Vena Cava filter (VCF) and the efficacy of the centralization mechanism of the filter. This retrospective cohort study evaluated all Braile Biomédica VCFs implanted from 2004 to 2009 in Hospital de Base Medicine School in São José do Rio Preto, Brazil. Of particular concern was the filter's symmetry during implantation and complications experienced during the procedure. All the angiographic examinations performed during the implantation of the filters were analyzed in respect to the following parameters: migration of the filter, non-opening or difficulties in the implantation and centralization of the filter. A total of 112 Braile CVFs were implanted and there were no reports of filter opening difficulties or in respect to migration. Asymmetry was observed in 1/112 (0.9%) cases. A statistically significant difference was seen on comparing historical data on decentralization of the Greenfield filter with the data of this study. The Braile Biomédico filter is an evolution of the Greenfield filter providing improved embolus capture and better implantation symmetry.

Quartz substrate infrared photonic crystal

Science.gov (United States)

Ghadiri, Khosrow; Rejeb, Jalel; Vitchev, Vladimir N.

2003-01-01

This paper presents the fabrication of a planar photonic crystal (p2c) made of a square array of dielectric rods embedded in air, operating in the infrared spectrum. A quartz substrate is employed instead of the commonly used silicon or column III-V substrate. Our square structure has a normalized cylinder radius-to-pitch ratio of r/a = 0.248 and dielectric material contrast ɛr of 4.5. We choose a Z-cut synthetic quartz for its cut (geometry), and etching properties. Then a particular Z-axis etching process is employed in order to ensure the sharp-edged verticality of the rods and fast etching speed. We also present the computer simulations that allowed the establishment of the photonic band gaps (PBG) of our photonic crystal, as well as the actual measurements. An experimental measurement have been carried out and compared with different simulations. It was found that experimental results are in good agreement with different simulation results. Finally, a frequency selective device for optical communication based on the introduction of impurity sites in the photonic crystal is presented. With our proposed structure Optical System on a Chip (OsoC) with micro-cavity based active devices such as lasers, diodes, modulators, couplers, frequency selective emitters, add-drop filters, detectors, mux/demuxes and polarizers connected by passive waveguide links can be realized.

Strain induced tunable wavelength filters based on flexible polymer waveguide Bragg reflector.

Science.gov (United States)

Kim, Kyung-Jo; Seo, Jun-Kyu; Oh, Min-Cheol

2008-02-04

A tunable wavelength filter is demonstrated by imposing a strain on a polymeric Bragg reflection waveguide fabricated on a flexible substrate. The highly elastic property of flexible polymer device enables much wider tuning than the silica fiber. To produce a uniform grating pattern on a flexible plastic substrate, a post lift-off process along with an absorbing layer is incorporated. The flexible Bragg reflector shows narrow bandwidth, which is convincing the uniformity of the grating structure fabricated on plastic film. By stretching the flexible polymer device, the Bragg reflection wavelength is tuned continuously up to 45 nm for the maximum strain of 31,690 muepsilon, which is determined by the elastic expansion limit of waveguide polymer. From the linear wavelength shift proportional to the strain, the photoelastic coefficient of the ZPU polymer is found.

Artificial intelligence

CERN Document Server

Ennals, J R

1987-01-01

Artificial Intelligence: State of the Art Report is a two-part report consisting of the invited papers and the analysis. The editor first gives an introduction to the invited papers before presenting each paper and the analysis, and then concludes with the list of references related to the study. The invited papers explore the various aspects of artificial intelligence. The analysis part assesses the major advances in artificial intelligence and provides a balanced analysis of the state of the art in this field. The Bibliography compiles the most important published material on the subject of

Backflushable filter insert

International Nuclear Information System (INIS)

Keith, R.C.; Vandenberg, T.; Randolph, M.C.; Lewis, T.B.; Gillis, P.J. Jr.

1988-01-01

Filter elements are mounted on a tube plate beneath an accumulator chamber whose wall is extended by skirt and flange to form a closure for the top of pressure vessel. The accumulator chamber is annular around a central pipe which serves as the outlet for filtered water passing from the filter elements. The chamber contains filtered compressed air from supply. Periodically the filtration of water is stopped and vessel is drained. Then a valve is opened, allowing the accumulated air to flow from chamber up a pipe and down pipe, pushing the filtered water from pipe back through the filter elements to clean them. The accumulator chamber is so proportioned, relative to the volume of the system communicating therewith during backflushing, that the equilibrium pressure during backflushing cannot exceed the pressure rating of the vessel. However a line monitors the pressure at the top of the vessel, and if it rises too far a bleed valve is automatically opened to depressurise the system. The chamber is intended to replace the lid of an existing vessel to convert a filter using filter aid to one using permanent filter elements. (author)

ECG Denoising Using Marginalized Particle Extended Kalman Filter With an Automatic Particle Weighting Strategy.

Science.gov (United States)

Hesar, Hamed Danandeh; Mohebbi, Maryam

2017-05-01

In this paper, a model-based Bayesian filtering framework called the "marginalized particle-extended Kalman filter (MP-EKF) algorithm" is proposed for electrocardiogram (ECG) denoising. This algorithm does not have the extended Kalman filter (EKF) shortcoming in handling non-Gaussian nonstationary situations because of its nonlinear framework. In addition, it has less computational complexity compared with particle filter. This filter improves ECG denoising performance by implementing marginalized particle filter framework while reducing its computational complexity using EKF framework. An automatic particle weighting strategy is also proposed here that controls the reliance of our framework to the acquired measurements. We evaluated the proposed filter on several normal ECGs selected from MIT-BIH normal sinus rhythm database. To do so, artificial white Gaussian and colored noises as well as nonstationary real muscle artifact (MA) noise over a range of low SNRs from 10 to -5 dB were added to these normal ECG segments. The benchmark methods were the EKF and extended Kalman smoother (EKS) algorithms which are the first model-based Bayesian algorithms introduced in the field of ECG denoising. From SNR viewpoint, the experiments showed that in the presence of Gaussian white noise, the proposed framework outperforms the EKF and EKS algorithms in lower input SNRs where the measurements and state model are not reliable. Owing to its nonlinear framework and particle weighting strategy, the proposed algorithm attained better results at all input SNRs in non-Gaussian nonstationary situations (such as presence of pink noise, brown noise, and real MA). In addition, the impact of the proposed filtering method on the distortion of diagnostic features of the ECG was investigated and compared with EKF/EKS methods using an ECG diagnostic distortion measure called the "Multi-Scale Entropy Based Weighted Distortion Measure" or MSEWPRD. The results revealed that our proposed

Filter replacement lifetime prediction

Science.gov (United States)

Hamann, Hendrik F.; Klein, Levente I.; Manzer, Dennis G.; Marianno, Fernando J.

2017-10-25

Methods and systems for predicting a filter lifetime include building a filter effectiveness history based on contaminant sensor information associated with a filter; determining a rate of filter consumption with a processor based on the filter effectiveness history; and determining a remaining filter lifetime based on the determined rate of filter consumption. Methods and systems for increasing filter economy include measuring contaminants in an internal and an external environment; determining a cost of a corrosion rate increase if unfiltered external air intake is increased for cooling; determining a cost of increased air pressure to filter external air; and if the cost of filtering external air exceeds the cost of the corrosion rate increase, increasing an intake of unfiltered external air.

Anti-clogging filter system

Science.gov (United States)

Brown, Erik P.

2015-05-19

An anti-clogging filter system for filtering a fluid containing large particles and small particles includes an enclosure with at least one individual elongated tubular filter element in the enclosure. The individual elongated tubular filter element has an internal passage, a closed end, an open end, and a filtering material in or on the individual elongated tubular filter element. The fluid travels through the open end of the elongated tubular element and through the internal passage and through the filtering material. An anti-clogging element is positioned on or adjacent the individual elongated tubular filter element and provides a fluid curtain that preferentially directs the larger particulates to one area of the filter material allowing the remainder of the filter material to remain more efficient.

Object-oriented alarm-filtering system

International Nuclear Information System (INIS)

Corsberg, D.R.; Wilkie, D.

1986-01-01

This paper discusses an alarm-filtering system (AFS) being developed by EG and G Idaho, Inc. for the Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory. The ultimate goal of this project is to place AFS into ATR's reactor control room to act as an aid during major plant transients. In addition, methods of alarm analysis are investigated based on functional relationships rather than on a historical approach utilizing cause-consequence trees. Artificial intelligence techniques, including object-oriented programming, are also demonstrated as useful in analyzing alarms and alarm sequences. After a brief description of the problem AFS addresses, this paper discusses the design constraints and human factors that influenced the development of the system. The reader is then presented with operational and architectural descriptions of the system as well as what directions the future development of AFS may take. The fact that AFS is being considered as a partial solution to the problems discussed in the next section demonstrates the viability of its underlying technology and approach. 10 refs

Fractional order integration and fuzzy logic based filter for denoising of echocardiographic image.

Science.gov (United States)

Saadia, Ayesha; Rashdi, Adnan

2016-12-01

Ultrasound is widely used for imaging due to its cost effectiveness and safety feature. However, ultrasound images are inherently corrupted with speckle noise which severely affects the quality of these images and create difficulty for physicians in diagnosis. To get maximum benefit from ultrasound imaging, image denoising is an essential requirement. To perform image denoising, a two stage methodology using fuzzy weighted mean and fractional integration filter has been proposed in this research work. In stage-1, image pixels are processed by applying a 3 × 3 window around each pixel and fuzzy logic is used to assign weights to the pixels in each window, replacing central pixel of the window with weighted mean of all neighboring pixels present in the same window. Noise suppression is achieved by assigning weights to the pixels while preserving edges and other important features of an image. In stage-2, the resultant image is further improved by fractional order integration filter. Effectiveness of the proposed methodology has been analyzed for standard test images artificially corrupted with speckle noise and real ultrasound B-mode images. Results of the proposed technique have been compared with different state-of-the-art techniques including Lsmv, Wiener, Geometric filter, Bilateral, Non-local means, Wavelet, Perona et al., Total variation (TV), Global Adaptive Fractional Integral Algorithm (GAFIA) and Improved Fractional Order Differential (IFD) model. Comparison has been done on quantitative and qualitative basis. For quantitative analysis different metrics like Peak Signal to Noise Ratio (PSNR), Speckle Suppression Index (SSI), Structural Similarity (SSIM), Edge Preservation Index (β) and Correlation Coefficient (ρ) have been used. Simulations have been done using Matlab. Simulation results of artificially corrupted standard test images and two real Echocardiographic images reveal that the proposed method outperforms existing image denoising techniques

Selection vector filter framework

Science.gov (United States)

Lukac, Rastislav; Plataniotis, Konstantinos N.; Smolka, Bogdan; Venetsanopoulos, Anastasios N.

2003-10-01

We provide a unified framework of nonlinear vector techniques outputting the lowest ranked vector. The proposed framework constitutes a generalized filter class for multichannel signal processing. A new class of nonlinear selection filters are based on the robust order-statistic theory and the minimization of the weighted distance function to other input samples. The proposed method can be designed to perform a variety of filtering operations including previously developed filtering techniques such as vector median, basic vector directional filter, directional distance filter, weighted vector median filters and weighted directional filters. A wide range of filtering operations is guaranteed by the filter structure with two independent weight vectors for angular and distance domains of the vector space. In order to adapt the filter parameters to varying signal and noise statistics, we provide also the generalized optimization algorithms taking the advantage of the weighted median filters and the relationship between standard median filter and vector median filter. Thus, we can deal with both statistical and deterministic aspects of the filter design process. It will be shown that the proposed method holds the required properties such as the capability of modelling the underlying system in the application at hand, the robustness with respect to errors in the model of underlying system, the availability of the training procedure and finally, the simplicity of filter representation, analysis, design and implementation. Simulation studies also indicate that the new filters are computationally attractive and have excellent performance in environments corrupted by bit errors and impulsive noise.

Changing ventilation filters

International Nuclear Information System (INIS)

Hackney, S.

1980-01-01

A filter changing unit has a door which interlocks with the door of a filter chamber so as to prevent contamination of the outer surfaces of the doors by radioactive material collected on the filter element and a movable support which enables a filter chamber thereonto to be stored within the unit in such a way that the doors of the unit and the filter chamber can be replaced. The door pivots and interlocks with another door by means of a bolt, a seal around the periphery lip of the first door engages the periphery of the second door to seal the gap. A support pivots into a lower filter element storage position. Inspection windows and glove ports are provided. The unit is releasably connected to the filter chamber by bolts engaging in a flange provided around an opening. (author)

Use of soil-like substrate for growing plant to enhance closedness of biological lie support system

Science.gov (United States)

Gros, J. B.; Lasseur, C.; Tikhomirov, A. A.; Manuskovsky, N. S.; Kovalev, V. S.; Ushakova, S. A.; Zolotukhin, I. G.; Tirranen, L. S.; Gribovskaya, I. V.

Soil-like substrate (SLS) a potential candidate for use for growing plants in closed biological life support systems (BLSS) was studied. SLS was made by successive transformation of wheat straw by oyster mushrooms and Californian worms. Fertility of SLS of different degree of maturity has been tested. Mature SLS contained 9.5 % of humus acids and 4.9 % of fulvic acids. Wheat, bean and cucumber crops cultivated on mature SLS were comparable to crops obtained on a neutral substrate (expanded clay aggregate). In the wheat-SLS system, net CO2 absorption started on the sixth day after sowing and stopped 5 days prior to harvesting whereas in the wheat-neutral substrate system, net CO2 absorption was registered throughout vegetation. In the SLS, dominant bacteria included the spore-forming bacteria of the Bacillus genus and dominant fungi included the genus Trichoderma. In the hydroponic cultivation on neutral substrate dominant bacteria were of the Pseudomonas genus, while most commonly found fungi were species of the Fusarium genus. Consequence of SLS incorporation in artificial BLSS for increasing the closure degree of internal mass exchange in comparison with a neutral substrate is considered.

A multiband THz bandpass filter based on multiple-resonance excitation of a composite metamaterial

International Nuclear Information System (INIS)

Chen, Xu; Fan, Wen-Hui

2015-01-01

We present a systematic numerical study on a metal-dielectric-metal (MDM) sandwich structure for multiple resonance transmission in terahertz (THz) region. The designed structure consists of periodic square close ring array on both side of a flexible dielectric substrate, exhibits a multiband transmission, with low average insertion loss, steep skirts and high out-of-band rejection. In addition, due to its rotationally symmetric structure, this filter is polarization-insensitive for normal incidence of the electromagnetic waves, keeping highly transmission at a wide range of incident angles for transverse electric waves and transverse magnetic waves. The metamaterial structure can be utilized as a desirable multiband filter with many practical applications, especially for THz communication, spectroscopic detection and phase imaging. (paper)

Comparative study of photocatalytic oxidation on the degradation of formaldehyde and fuzzy mathematics evaluation of filters

Science.gov (United States)

Yu, Huili; Zhang, Jieting

2012-04-01

In this study, formaldehyde, one of the major volatile organic compounds, is chosen as the target pollutant. The polytetrafluoroethylene (PTFE) filter, a low cost and commonly used material in industry, is employed as the substrate for nano TiO2 photocatalyst coating at room temperature, which has been scarcely used compared to ceramics or glass beads. Furthermore, a specific experimental set-up that is similar to actual air purification system is developed for the testing. The degradation mechanisms of photolysis reaction, adsorption and photocatalytic oxidation reaction on volatile organic compounds are present respectively. The influences of three aspects mentioned above are compared by a serial of experimental data. The high efficiency of volatile organic compounds on the degradation of formaldehyde is assured. Furthermore, the purification characteristics of three kinds of activated carbon filters and PTFE filter with nano TiO2 are evaluated with the method of fuzzy mathematics. In the end, the result shows that the filter with nano TiO2 has the optimal comprehensive performances.

Device for automatic filter changing. Einrichtung zum selbsttaetigen Wechseln eines Filters

Energy Technology Data Exchange (ETDEWEB)

Matschoss, V; Naschwitz, A; Wild, H

1984-01-05

A filter is moved from a store to an aerosol pipe by a lifting device and is clamped there. At the end of the operating period, the lifting device moves a new filter to a parking place. Control is from limit switches of the lifting, clamping and thrust devices and the position control of the store is by the limit switches. The filter changing device is enclosed in a gastight case, prevents blockage of a filter and makes it possible to set a certain operating period, to change the filter without interrupting the aerosol flow and to measure each filter in the sequence of operation outside the aerosol flow.

Sensory pollution from bag-type fiberglass ventilation filters: Conventional filter compared with filters containing various amounts of activated carbon

DEFF Research Database (Denmark)

Bekö, Gabriel; Fadeyi, M.O.; Clausen, Geo

2009-01-01

filter and three modifications of a bag-type fiberglass combination filter: the "Heavy" corresponded to a commercially available filter containing 400 g of carbon per square meter of filter area, the "Medium" contained half as much carbon (200 g/m(2)), and the "Light" contained a quarter as much carbon...

Study of SNS and SIS NbN Josephson junctions coupled to a microwave band-pass filter

Energy Technology Data Exchange (ETDEWEB)

Baggetta, E; Setzu, R; Villegier, J C [Laboratoire de Cryophysique, DRFMC, CEA, Grenoble (France)

2006-06-01

We have fabricated both NbN/Ta{sub x}N/NbN SN*S-type, NbN/MgO/NbN SIS-type Josephson junctions and microwave band-pass filters on different substrates (Si, Sapphire, MgO). NbN films have been deposited on both sides of (100) oriented, 250 {mu}m thick, MgO substrates with a high crystalline texture quality. The aim was to investigate the performances and the maximum achievable operating frequency in an NbN based RSFQ modulator front-end of an ADC in the 4 K-10 K temperature range. We observed that Ta{sub x}N thin films can be tuned from an insulating phase to a superconducting phase (Tc {approx}4K) by varying the nitrogen content during sputter deposition while the barrier height of MgO can also be controlled by deposition conditions and by tri-layer postdeposition annealing. Junction properties (Jc{approx}10-25 kA/cm{sup 2}), Mac Cumber parameter and RnIc product measured up to 1 mV are shown to be controlled by the reactive sputtering conditions. We have designed three pole band-pass filters and resonators in a micro-strip configuration and studied the junction coupling with the filters. We will show that a sigma-delta NbN technology is a suitable solution for analogue-to-digital conversion in the future generations of telecommunication satellites to achieve high sampling frequency and large bandwidth at high carrier frequency signal.

Study of SNS and SIS NbN Josephson junctions coupled to a microwave band-pass filter

International Nuclear Information System (INIS)

Baggetta, E; Setzu, R; Villegier, J C

2006-01-01

We have fabricated both NbN/Ta x N/NbN SN*S-type, NbN/MgO/NbN SIS-type Josephson junctions and microwave band-pass filters on different substrates (Si, Sapphire, MgO). NbN films have been deposited on both sides of (100) oriented, 250 μm thick, MgO substrates with a high crystalline texture quality. The aim was to investigate the performances and the maximum achievable operating frequency in an NbN based RSFQ modulator front-end of an ADC in the 4 K-10 K temperature range. We observed that Ta x N thin films can be tuned from an insulating phase to a superconducting phase (Tc ∼4K) by varying the nitrogen content during sputter deposition while the barrier height of MgO can also be controlled by deposition conditions and by tri-layer postdeposition annealing. Junction properties (Jc∼10-25 kA/cm 2 ), Mac Cumber parameter and RnIc product measured up to 1 mV are shown to be controlled by the reactive sputtering conditions. We have designed three pole band-pass filters and resonators in a micro-strip configuration and studied the junction coupling with the filters. We will show that a sigma-delta NbN technology is a suitable solution for analogue-to-digital conversion in the future generations of telecommunication satellites to achieve high sampling frequency and large bandwidth at high carrier frequency signal

A Differential Geometric Approach to Nonlinear Filtering: The Projection Filter

NARCIS (Netherlands)

Brigo, D.; Hanzon, B.; LeGland, F.

1998-01-01

This paper presents a new and systematic method of approximating exact nonlinear filters with finite dimensional filters, using the differential geometric approach to statistics. The projection filter is defined rigorously in the case of exponential families. A convenient exponential family is

Filter and Filter Bank Design for Image Texture Recognition

Energy Technology Data Exchange (ETDEWEB)

Randen, Trygve

1997-12-31

The relevance of this thesis to energy and environment lies in its application to remote sensing such as for instance sea floor mapping and seismic pattern recognition. The focus is on the design of two-dimensional filters for feature extraction, segmentation, and classification of digital images with textural content. The features are extracted by filtering with a linear filter and estimating the local energy in the filter response. The thesis gives a review covering broadly most previous approaches to texture feature extraction and continues with proposals of some new techniques. 143 refs., 59 figs., 7 tabs.

HEPA Filter Vulnerability Assessment

International Nuclear Information System (INIS)

GUSTAVSON, R.D.

2000-01-01

This assessment of High Efficiency Particulate Air (HEPA) filter vulnerability was requested by the USDOE Office of River Protection (ORP) to satisfy a DOE-HQ directive to evaluate the effect of filter degradation on the facility authorization basis assumptions. Within the scope of this assessment are ventilation system HEPA filters that are classified as Safety-Class (SC) or Safety-Significant (SS) components that perform an accident mitigation function. The objective of the assessment is to verify whether HEPA filters that perform a safety function during an accident are likely to perform as intended to limit release of hazardous or radioactive materials, considering factors that could degrade the filters. Filter degradation factors considered include aging, wetting of filters, exposure to high temperature, exposure to corrosive or reactive chemicals, and exposure to radiation. Screening and evaluation criteria were developed by a site-wide group of HVAC engineers and HEPA filter experts from published empirical data. For River Protection Project (RPP) filters, the only degradation factor that exceeded the screening threshold was for filter aging. Subsequent evaluation of the effect of filter aging on the filter strength was conducted, and the results were compared with required performance to meet the conditions assumed in the RPP Authorization Basis (AB). It was found that the reduction in filter strength due to aging does not affect the filter performance requirements as specified in the AB. A portion of the HEPA filter vulnerability assessment is being conducted by the ORP and is not part of the scope of this study. The ORP is conducting an assessment of the existing policies and programs relating to maintenance, testing, and change-out of HEPA filters used for SC/SS service. This document presents the results of a HEPA filter vulnerability assessment conducted for the River protection project as requested by the DOE Office of River Protection

Correlation of antispermatozoal antibody with infertility in immunized female rabbits using 14C-protein A in a filter radioassay

International Nuclear Information System (INIS)

Eng, L.A.; Metz, C.B.

1986-01-01

The meaningful detection of antisperm antibody in immunologically infertile females has been confounded by the many methods of assay that exist. With many of these methods there is poor correlation of assay results with infertility. In this report, female rabbits were rendered partially or completely infertile by immunization with sperm fractions. A filter radioassay for antisperm antibody was developed that consists of incubating 10(7) sperm with sperm from immunized rabbits and 14 C-Protein A, a long-lived and versatile indirect radiolabel for many antibodies of the IgG class. The spermatozoa are washed by rapid vacuum filtration on polycarbonate membrane filters instead of by time-consuming centrifugation. The filters with the collected spermatozoa are then counted in a liquid scintillation counter. Sera from female rabbits isoimmunized with sperm antigens show a highly significant correlation (r = -0.904; p less than 0.001) between assay results and infertility as measured by the percentage of eggs that underwent cleavage after artificial insemination

Potential for HEPA filter damage from water spray systems in filter plenums

Energy Technology Data Exchange (ETDEWEB)

Bergman, W. [Lawrence Livermore National Lab., CA (United States); Fretthold, J.K. [Rocky Flats Safe Sites of Colorado, Golden, CO (United States); Slawski, J.W. [Department of Energy, Germantown, MD (United States)

1997-08-01

The water spray systems in high efficiency particulate air (HEPA) filter plenums that are used in nearly all Department of Energy (DOE) facilities for protection against fire was designed under the assumption that the HEPA filters would not be damaged by the water sprays. The most likely scenario for filter damage involves filter plugging by the water spray, followed by the fan blowing out the filter medium. A number of controlled laboratory tests that were previously conducted in the late 1980s are reviewed in this paper to provide a technical basis for the potential HEPA filter damage by the water spray system in HEPA filter plenums. In addition to the laboratory tests, the scenario for BEPA filter damage during fires has also occurred in the field. A fire in a four-stage, BEPA filter plenum at Rocky Flats in 1980 caused the first three stages of BEPA filters to blow out of their housing and the fourth stage to severely bow. Details of this recently declassified fire are presented in this paper. Although these previous findings suggest serious potential problems exist with the current water spray system in filter plenums, additional studies are required to confirm unequivocally that DOE`s critical facilities are at risk. 22 refs., 15 figs.

Artificial Leaf Based on Artificial Photosynthesis for Solar Fuel Production

Science.gov (United States)

2017-06-30

collect light energy and separate charge for developing new types of nanobiodevices to construct ”artificial leaf” from solar to fuel. or Concept of...AFRL-AFOSR-JP-TR-2017-0054 Artificial Leaf Based on Artificial Photosynthesis for Solar Fuel Production Mamoru Nango NAGOYA INSTITUTE OF TECHNOLOGY...display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ORGANIZATION. 1. REPORT DATE (DD-MM-YYYY)      30-06-2017 2

Neutron Beam Filters

International Nuclear Information System (INIS)

Adib, M.

2011-01-01

The purpose of filters is to transmit neutrons with selected energy, while remove unwanted ones from the incident neutron beam. This reduces the background, and the number of spurious. The types of commonly used now-a-day neutron filters and their properties are discussed in the present work. There are three major types of neutron filters. The first type is filter of selective thermal neutron. It transmits the main reflected neutrons from a crystal monochromate, while reject the higher order contaminations accompanying the main one. Beams coming from the moderator always contain unwanted radiation like fast neutrons and gamma-rays which contribute to experimental background and to the biological hazard potential. Such filter type is called filter of whole thermal neutron spectrum. The third filter type is it transmits neutrons with energies in the resonance energy range (En . 1 KeV). The main idea of such neutron filter technique is the use of large quantities of a certain material which have the deep interference minima in its total neutron cross-section. By transmitting reactor neutrons through bulk layer of such material, one can obtain the quasimonochromatic neutron lines instead of white reactor spectrum.

Two-dimensional modeling of water and heat fluxes in green roof substrates

Science.gov (United States)

Suarez, F. I.; Sandoval, V. P.

2016-12-01

Due to public concern towards sustainable development, greenhouse gas emissions and energy efficiency, green roofs have become popular in the last years. Green roofs integrate vegetation into infrastructures to reach additional benefits that minimize negative impacts of the urbanization. A properly designed green roof can reduce environmental pollution, noise levels, energetic requirements or surface runoff. The correct performance of green roofs depends on site-specific conditions and on each component of the roof. The substrate and the vegetation layers strongly influence water and heat fluxes on a green roof. The substrate is an artificial media that has an improved performance compared to natural soils as it provides critical resources for vegetation survival: water, nutrients, and a growing media. Hence, it is important to study the effects of substrate properties on green roof performance. The objective of this work is to investigate how the thermal and hydraulic properties affect the behavior of a green roof through numerical modeling. The substrates that were investigated are composed by: crushed bricks and organic soil (S1); peat with perlite (S2); crushed bricks (S3); mineral soil with tree leaves (S4); and a mixture of topsoil and mineral soil (S5). The numerical model utilizes summer-arid meteorological information to evaluate the performance of each substrate. Results show that the area below the water retention curve helps to define the substrate that retains more water. In addition, the non-linearity of the water retention curve can increment the water needed to irrigate the roof. The heat propagation through the roof depends strongly on the hydraulic behavior, meaning that a combination of a substrate with low thermal conductivity and more porosity can reduce the heat fluxes across the roof. Therefore, it can minimize the energy consumed of an air-conditioner system.

Miniaturized dielectric waveguide filters

OpenAIRE

Sandhu, MY; Hunter, IC

2016-01-01

Design techniques for a new class of integrated monolithic high-permittivity ceramic waveguide filters are presented. These filters enable a size reduction of 50% compared to air-filled transverse electromagnetic filters with the same unloaded Q-factor. Designs for Chebyshev and asymmetric generalised Chebyshev filter and a diplexer are presented with experimental results for an 1800 MHz Chebyshev filter and a 1700 MHz generalised Chebyshev filter showing excellent agreement with theory.

Concrete ensemble Kalman filters with rigorous catastrophic filter divergence.

Science.gov (United States)

Kelly, David; Majda, Andrew J; Tong, Xin T

2015-08-25

The ensemble Kalman filter and ensemble square root filters are data assimilation methods used to combine high-dimensional, nonlinear dynamical models with observed data. Ensemble methods are indispensable tools in science and engineering and have enjoyed great success in geophysical sciences, because they allow for computationally cheap low-ensemble-state approximation for extremely high-dimensional turbulent forecast models. From a theoretical perspective, the dynamical properties of these methods are poorly understood. One of the central mysteries is the numerical phenomenon known as catastrophic filter divergence, whereby ensemble-state estimates explode to machine infinity, despite the true state remaining in a bounded region. In this article we provide a breakthrough insight into the phenomenon, by introducing a simple and natural forecast model that transparently exhibits catastrophic filter divergence under all ensemble methods and a large set of initializations. For this model, catastrophic filter divergence is not an artifact of numerical instability, but rather a true dynamical property of the filter. The divergence is not only validated numerically but also proven rigorously. The model cleanly illustrates mechanisms that give rise to catastrophic divergence and confirms intuitive accounts of the phenomena given in past literature.

Effects of laminin blended with chitosan on axon guidance on patterned substrates

Energy Technology Data Exchange (ETDEWEB)

Zhu, N; Guan, Y J; Chen, X B [Division of Biomedical Engineering, University of Saskatchewan, Saskatoon S7N 5A9 (Canada); Li, M G [Department of Mechanical Engineering, University of Saskatchewan, Saskatoon S7N 5A9 (Canada); Schreyer, D J, E-mail: niz504@mail.usask.c [Department of Anatomy and Cell Biology, Cameco MS Neuroscience Research Center, University of Saskatchewan, Saskatoon, S7K 0M7 (Canada)

2010-12-15

Axon guidance is a crucial consideration in the design of tissue scaffolds used to promote nerve regeneration. Here we investigate the combined use of laminin (a putative axon adhesion and guidance molecule) and chitosan (a leading candidate base material for the construction of scaffolds) for promoting axon guidance in cultured adult dorsal root ganglion (DRG) neurons. Using a dispensing-based rapid prototyping (DBRP) technique, two-dimensional grid patterns were created by dispensing chitosan or laminin-blended chitosan substrate strands oriented in orthogonal directions. In vitro experiments illustrated DRG neurites on these patterns preferentially grew upon and followed the laminin-blended chitosan pathways. These results suggest that an orientation of neurite growth can be achieved in an artificially patterned substrate by creating selectively biofunctional pathways. The DBRP technique may provide improved strategies for the use of biofunctional pathways in the design of three-dimensional scaffolds for guidance of nerve repair.

Effects of laminin blended with chitosan on axon guidance on patterned substrates

International Nuclear Information System (INIS)

Zhu, N; Guan, Y J; Chen, X B; Li, M G; Schreyer, D J

2010-01-01

Axon guidance is a crucial consideration in the design of tissue scaffolds used to promote nerve regeneration. Here we investigate the combined use of laminin (a putative axon adhesion and guidance molecule) and chitosan (a leading candidate base material for the construction of scaffolds) for promoting axon guidance in cultured adult dorsal root ganglion (DRG) neurons. Using a dispensing-based rapid prototyping (DBRP) technique, two-dimensional grid patterns were created by dispensing chitosan or laminin-blended chitosan substrate strands oriented in orthogonal directions. In vitro experiments illustrated DRG neurites on these patterns preferentially grew upon and followed the laminin-blended chitosan pathways. These results suggest that an orientation of neurite growth can be achieved in an artificially patterned substrate by creating selectively biofunctional pathways. The DBRP technique may provide improved strategies for the use of biofunctional pathways in the design of three-dimensional scaffolds for guidance of nerve repair.

Hybrid Filter Membrane

Science.gov (United States)

Laicer, Castro; Rasimick, Brian; Green, Zachary

2012-01-01

Cabin environmental control is an important issue for a successful Moon mission. Due to the unique environment of the Moon, lunar dust control is one of the main problems that significantly diminishes the air quality inside spacecraft cabins. Therefore, this innovation was motivated by NASA s need to minimize the negative health impact that air-suspended lunar dust particles have on astronauts in spacecraft cabins. It is based on fabrication of a hybrid filter comprising nanofiber nonwoven layers coated on porous polymer membranes with uniform cylindrical pores. This design results in a high-efficiency gas particulate filter with low pressure drop and the ability to be easily regenerated to restore filtration performance. A hybrid filter was developed consisting of a porous membrane with uniform, micron-sized, cylindrical pore channels coated with a thin nanofiber layer. Compared to conventional filter media such as a high-efficiency particulate air (HEPA) filter, this filter is designed to provide high particle efficiency, low pressure drop, and the ability to be regenerated. These membranes have well-defined micron-sized pores and can be used independently as air filters with discreet particle size cut-off, or coated with nanofiber layers for filtration of ultrafine nanoscale particles. The filter consists of a thin design intended to facilitate filter regeneration by localized air pulsing. The two main features of this invention are the concept of combining a micro-engineered straight-pore membrane with nanofibers. The micro-engineered straight pore membrane can be prepared with extremely high precision. Because the resulting membrane pores are straight and not tortuous like those found in conventional filters, the pressure drop across the filter is significantly reduced. The nanofiber layer is applied as a very thin coating to enhance filtration efficiency for fine nanoscale particles. Additionally, the thin nanofiber coating is designed to promote capture of

Generative Artificial Intelligence : Philosophy and Theory of Artificial Intelligence

NARCIS (Netherlands)

van der Zant, Tijn; Kouw, Matthijs; Schomaker, Lambertus; Mueller, Vincent C.

2013-01-01

The closed systems of contemporary Artificial Intelligence do not seem to lead to intelligent machines in the near future. What is needed are open-ended systems with non-linear properties in order to create interesting properties for the scaffolding of an artificial mind. Using post-structuralistic

Artificial fish skin of self-powered micro-electromechanical systems hair cells for sensing hydrodynamic flow phenomena.

Science.gov (United States)

Asadnia, Mohsen; Kottapalli, Ajay Giri Prakash; Miao, Jianmin; Warkiani, Majid Ebrahimi; Triantafyllou, Michael S

2015-10-06

Using biological sensors, aquatic animals like fishes are capable of performing impressive behaviours such as super-manoeuvrability, hydrodynamic flow 'vision' and object localization with a success unmatched by human-engineered technologies. Inspired by the multiple functionalities of the ubiquitous lateral-line sensors of fishes, we developed flexible and surface-mountable arrays of micro-electromechanical systems (MEMS) artificial hair cell flow sensors. This paper reports the development of the MEMS artificial versions of superficial and canal neuromasts and experimental characterization of their unique flow-sensing roles. Our MEMS flow sensors feature a stereolithographically fabricated polymer hair cell mounted on Pb(Zr(0.52)Ti(0.48))O3 micro-diaphragm with floating bottom electrode. Canal-inspired versions are developed by mounting a polymer canal with pores that guide external flows to the hair cells embedded in the canal. Experimental results conducted employing our MEMS artificial superficial neuromasts (SNs) demonstrated a high sensitivity and very low threshold detection limit of 22 mV/(mm s(-1)) and 8.2 µm s(-1), respectively, for an oscillating dipole stimulus vibrating at 35 Hz. Flexible arrays of such superficial sensors were demonstrated to localize an underwater dipole stimulus. Comparative experimental studies revealed a high-pass filtering nature of the canal encapsulated sensors with a cut-off frequency of 10 Hz and a flat frequency response of artificial SNs. Flexible arrays of self-powered, miniaturized, light-weight, low-cost and robust artificial lateral-line systems could enhance the capabilities of underwater vehicles. © 2015 The Author(s).

Trophic availability buffers the detrimental effects of clogging in an alpine stream.

Science.gov (United States)

Doretto, Alberto; Bona, Francesca; Piano, Elena; Zanin, Ilaria; Eandi, Anna Chiara; Fenoglio, Stefano

2017-08-15

Clogging, the streambed colmation by fine sediments, is an important widespread source of impact affecting freshwaters. Alterations in stream morphology and hydrology, added to the effects of global climate change, are responsible for this phenomenon, that is particularly pernicious in mountainous lotic systems naturally characterized by coarse substrates. Among the studies investigating this issue some were descriptive, while others used artificial substrates to compare ongoing fine sediment accumulation and macroinvertebrate assemblage recruitment. Other studies used from the outset artificial substrates arranged with different levels of clogging. Our study fits into this line, but adding an innovative element simulating different availability of coarse particulate organic matter, i.e. the main trophic input in low-order, mountainous stream. To investigate how clogging and CPOM can influence macroinvertebrate communities, we placed 135 artificial substrates in the upper Po river (NW Italy). We set up a three way factorial design with three different levels of sedimentation and terrestrial leaf material. Artificial substrates were removed on three different dates. Benthic invertebrates were identified and classified according to their bio-ecological traits. We also measured macroinvertebrate dry mass and CPOM degradation in the different trap types. Our findings show that clogging acts as a selective filter influencing taxa richness, density, functional composition and biomass of benthic assemblage. Moreover, fine sediments affect the energetic dynamics in the river ecosystem, decreasing the mass loss rate of terrestrial leaves. Interestingly, our results clearly demonstrate that high availability of CPOM can buffer the negative effect of clogging, suggesting that an adequate input of allochthonous organic matter may lessen the impact of fine sediment deposition. Because land use transformation and removal of wooded riparian areas increase clogging and

Artificial life and Piaget.

Science.gov (United States)

Mueller, Ulrich; Grobman, K H.

2003-04-01

Artificial life provides important theoretical and methodological tools for the investigation of Piaget's developmental theory. This new method uses artificial neural networks to simulate living phenomena in a computer. A recent study by Parisi and Schlesinger suggests that artificial life might reinvigorate the Piagetian framework. We contrast artificial life with traditional cognitivist approaches, discuss the role of innateness in development, and examine the relation between physiological and psychological explanations of intelligent behaviour.

Fibronectin-tethered graphene oxide as an artificial matrix for osteogenesis

International Nuclear Information System (INIS)

Subbiah, Ramesh; Du, Ping; Van, Se Young; Suhaeri, Muhammad; Lee, Kangwon; Park, Kwideok; Hwang, Mintai P

2014-01-01

An artificial matrix (Fn-Tigra), consisting of graphene oxide (GO) and fibronectin (Fn), is developed on pure titanium (Ti) substrates via an electrodropping technique assisted with a custom-made coaxial needle. The morphology and topography of the resulting artificial matrix is orderly aligned and composed of porous microcavities. In addition, Fn is homogenously distributed and firmly bound onto GO as determined via immunofluorescence and elemental mapping, respectively. The artificial matrix is moderately hydrophobic (63.7°), and exhibits an average roughness of 546 nm and a Young’s modulus (E) of approximately 4.8 GPa. The biocompatibility, cellular behavior, and osteogenic potential of preosteoblasts on Fn-Tigra are compared to those of cells cultured on Ti and Ti-GO (Tigra). Cell proliferation and viability are significantly higher on Fn-Tigra and Tigra than that of cells grown on Ti. Focal adhesion molecule (vinculin) expression is highly activated at the central and peripheral area of preosteoblasts when cultured on Fn-Tigra. Furthermore, we demonstrate enhanced in vitro osteogenic differentiation of preosteoblasts cultured on Fn-Tigra over those cultured on bare Ti, as determined via Alizarin red and von Kossa staining, and the analysis of osteocalcin, type I collagen, alkaline phosphatase activity, and calcium contents. Finally, we investigate the biophysical and biomechanical properties of the cells using AFM. While the height and roughness of preosteoblasts increased with time, cell surface area decreased during in vitro osteogenesis over 2 weeks. In addition, the E of cells cultured on Tigra and Fn-Tigra increase in a statistically significant and time-dependent manner by 30%, while those cultured on bare Ti retain a relatively consistent E. In summary, we engineer a biocompatible artificial matrix (Fn-Tigra) capable of osteogenic induction and consequently demonstrate its potential in bone tissue engineering applications. (paper)

Fibronectin-tethered graphene oxide as an artificial matrix for osteogenesis.

Science.gov (United States)

Subbiah, Ramesh; Du, Ping; Van, Se Young; Suhaeri, Muhammad; Hwang, Mintai P; Lee, Kangwon; Park, Kwideok

2014-10-20

An artificial matrix (Fn-Tigra), consisting of graphene oxide (GO) and fibronectin (Fn), is developed on pure titanium (Ti) substrates via an electrodropping technique assisted with a custom-made coaxial needle. The morphology and topography of the resulting artificial matrix is orderly aligned and composed of porous microcavities. In addition, Fn is homogenously distributed and firmly bound onto GO as determined via immunofluorescence and elemental mapping, respectively. The artificial matrix is moderately hydrophobic (63.7°), and exhibits an average roughness of 546 nm and a Young's modulus (E) of approximately 4.8 GPa. The biocompatibility, cellular behavior, and osteogenic potential of preosteoblasts on Fn-Tigra are compared to those of cells cultured on Ti and Ti-GO (Tigra). Cell proliferation and viability are significantly higher on Fn-Tigra and Tigra than that of cells grown on Ti. Focal adhesion molecule (vinculin) expression is highly activated at the central and peripheral area of preosteoblasts when cultured on Fn-Tigra. Furthermore, we demonstrate enhanced in vitro osteogenic differentiation of preosteoblasts cultured on Fn-Tigra over those cultured on bare Ti, as determined via Alizarin red and von Kossa staining, and the analysis of osteocalcin, type I collagen, alkaline phosphatase activity, and calcium contents. Finally, we investigate the biophysical and biomechanical properties of the cells using AFM. While the height and roughness of preosteoblasts increased with time, cell surface area decreased during in vitro osteogenesis over 2 weeks. In addition, the E of cells cultured on Tigra and Fn-Tigra increase in a statistically significant and time-dependent manner by 30%, while those cultured on bare Ti retain a relatively consistent E. In summary, we engineer a biocompatible artificial matrix (Fn-Tigra) capable of osteogenic induction and consequently demonstrate its potential in bone tissue engineering applications.

Sampled data CT system including analog filter and compensating digital filter

International Nuclear Information System (INIS)

Glover, G. H.; DallaPiazza, D. G.; Pelc, N. J.

1985-01-01

A CT scanner in which the amount of x-ray information acquired per unit time is substantially increased by using a continuous-on x-ray source and a sampled data system with the detector. An analog filter is used in the sampling system for band limiting the detector signal below the highest frequency of interest, but is a practically realizable filter and is therefore non-ideal. A digital filter is applied to the detector data after digitization to compensate for the characteristics of the analog filter, and to provide an overall filter characteristic more nearly like the ideal

Quick-change filter cartridge

Science.gov (United States)

Rodgers, John C.; McFarland, Andrew R.; Ortiz, Carlos A.

1995-01-01

A quick-change filter cartridge. In sampling systems for measurement of airborne materials, a filter element is introduced into the sampled airstream such that the aerosol constituents are removed and deposited on the filter. Fragile sampling media often require support in order to prevent rupture during sampling, and careful mounting and sealing to prevent misalignment, tearing, or creasing which would allow the sampled air to bypass the filter. Additionally, handling of filter elements may introduce cross-contamination or exposure of operators to toxic materials. Moreover, it is desirable to enable the preloading of filter media into quick-change cartridges in clean laboratory environments, thereby simplifying and expediting the filter-changing process in the field. The quick-change filter cartridge of the present invention permits the application of a variety of filter media in many types of instruments and may also be used in automated systems. The cartridge includes a base through which a vacuum can be applied to draw air through the filter medium which is located on a porous filter support and held there by means of a cap which forms an airtight seal with the base. The base is also adapted for receiving absorbing media so that both particulates and gas-phase samples may be trapped for investigation, the latter downstream of the aerosol filter.

A large-area, wide-incident-angle, and polarization-independent plasmonic color filter for glucose sensing

Science.gov (United States)

Lin, Yu-Sheng; Chen, Wenjun

2018-01-01

We develop an effective method for glucose sensing by using a plasmonic color filter (PCF) integrated with a microfluidic chip. The morphology of PCF is composed of hybrid nanopillars fabricated with SiO2 and Au thin-films on silicon substrate. It exhibits angle-independence, polarization-independence and wafer-level fabrication, which are the most important factors for color filters for industrial applications. The shift of resonant wavelength is 56 nm with a stable bandwidth (∼30 nm) by varying concentration of glucose solution. The sensitivity is 157.61 nm/RIU and the corresponding figure-of-merit is 5.25. Such strategy can be exploited to further increase the detection and potentially enter the ultra-strong coupling regime in chemical solution sensors.

Relationships between substrate, surface characteristics, and vegetation in an initial ecosystem

Science.gov (United States)

Biber, P.; Seifert, S.; Zaplata, M. K.; Schaaf, W.; Pretzsch, H.; Fischer, A.

2013-12-01

We investigated surface and vegetation dynamics in the artificial initial ecosystem "Chicken Creek" (Lusatia, Germany) in the years 2006-2011 across a wide spectrum of empirical data. We scrutinized three overarching hypotheses concerning (1) the relations between initial geomorphological and substrate characteristics with surface structure and terrain properties, (2) the effects of the latter on the occurrence of grouped plant species, and (3) vegetation density effects on terrain surface change. Our data comprise and conflate annual vegetation monitoring results, biennial terrestrial laser scans (starting in 2008), annual groundwater levels, and initially measured soil characteristics. The empirical evidence mostly confirms the hypotheses, revealing statistically significant relations for several goal variables: (1) the surface structure properties, local rill density, local relief energy and terrain surface height change; (2) the cover of different plant groups (annual, herbaceous, grass-like, woody, Fabaceae), and local vegetation height; and (3) terrain surface height change showed significant time-dependent relations with a variable that proxies local plant biomass. Additionally, period specific effects (like a calendar-year optimum effect for the occurrence of Fabaceae) were proven. Further and beyond the hypotheses, our findings on the spatiotemporal dynamics during the system's early development grasp processes which generally mark the transition from a geo-hydro-system towards a bio-geo-hydro system (weakening geomorphology effects on substrate surface dynamics, while vegetation effects intensify with time), where pure geomorphology or substrate feedbacks are changing into vegetation-substrate feedback processes.

Improved Kalman Filter-Based Speech Enhancement with Perceptual Post-Filtering

Institute of Scientific and Technical Information of China (English)

WEIJianqiang; DULimin; YANZhaoli; ZENGHui

2004-01-01

In this paper, a Kalman filter-based speech enhancement algorithm with some improvements of previous work is presented. A new technique based on spectral subtraction is used for separation speech and noise characteristics from noisy speech and for the computation of speech and noise Autoregressive (AR) parameters. In order to obtain a Kalman filter output with high audible quality, a perceptual post-filter is placed at the output of the Kalman filter to smooth the enhanced speech spectra.Extensive experiments indicate that this newly proposed method works well.

Design and engineering of IZO/Ag/glass solar filters for low-emissivity window performance

Science.gov (United States)

Hernandez-Mainet, Luis C.; Aguilar, Miguel A.; Tamargo, Maria C.; Falcony, Ciro

2017-10-01

The electricity consumption in houses and commercial buildings generates about 18% of greenhouse gas emission. A critical issue of building energy consumption is heat and cooling loss through the window. Low-emissivity windows control thermal radiation through glass without decreasing the intensity of visible light. They are made up of optical filter coatings grown on a flat glass surface. Solar filters based on Ag/IZO multilayer films are grown and simulated on glass substrate. The targeted structure designs are grown by a sputtering system and characterized by scanning electron microscopy and x-ray diffraction techniques. To accurately simulate transmission spectrum, silver (Ag) and IZO optical constants were estimated by fitting ellipsometric data at different thicknesses. Transmission spectrum shows a good agreement among experiment and simulation. In addition, optical constant curves strongly show layer thickness dependence in both materials. In particular, the ultrathin Ag layer displays a percolation threshold in the vicinity of 15 nm, which leads to surface plasmon resonance with absorption at about 450 nm. These types of optical filter coatings would have potential applications as low-emission windows.

Method for cleaning the filter pockets of dust gas filter systems

Energy Technology Data Exchange (ETDEWEB)

Margraf, A

1975-05-07

The invention deals with a method to clean filter pockets filled with dust gas. By a periodic to and fro air jet attached to a scavenging blower, a pulsed fluttering movement of the filter surface is obtained which releases the outer layers of dust. The charging of the filter pockets with scavenging air to clean the filter material can be carried out immediately on the pulsed admission with suitable time control.

A Digital Image Denoising Algorithm Based on Gaussian Filtering and Bilateral Filtering

Directory of Open Access Journals (Sweden)

Piao Weiying

2018-01-01

Full Text Available Bilateral filtering has been applied in the area of digital image processing widely, but in the high gradient region of the image, bilateral filtering may generate staircase effect. Bilateral filtering can be regarded as one particular form of local mode filtering, according to above analysis, an mixed image de-noising algorithm is proposed based on Gaussian filter and bilateral filtering. First of all, it uses Gaussian filter to filtrate the noise image and get the reference image, then to take both the reference image and noise image as the input for range kernel function of bilateral filter. The reference image can provide the image’s low frequency information, and noise image can provide image’s high frequency information. Through the competitive experiment on both the method in this paper and traditional bilateral filtering, the experimental result showed that the mixed de-noising algorithm can effectively overcome staircase effect, and the filtrated image was more smooth, its textural features was also more close to the original image, and it can achieve higher PSNR value, but the amount of calculation of above two algorithms are basically the same.

Ethanol production by immobilized cells with forced substrate supply

Energy Technology Data Exchange (ETDEWEB)

Mitani, Y.; Nishizawa, Y.; Nagai, S.

1984-01-01

Ethanol fermentation by a forced substrate supply into an immobilized cell layer was carried out to increase the ethanol production rate and to eliminate the diffusion dependency of substrate supply in an ordinary immobilized cell reaction. Saccharomyces cerevisiae IFO 2347 was immobilized in a mixture of k-carrageenan, locust bean gum, and celite (2: 0.5: 40 wt/vol %). A glucose minimal medium was fed into the immobilized cell layer (5 to 22 mm in thickness) at retention times between 0.6 and 2.8 h under pressure. The stable ethanol fermentation could be maintained for more than 3 weeks with an ethanol yield of 0.48 g ethanol/g glucose and ethanol productivity of 63 g.(l gel)/sup -1/.h/sup -1/ at a retention time of 1.5 h. The yeast cells were well distributed through the gel layer with a vertical gradient, and an average cell density was ca. 8.0 X 10/sup 9/ cells/ml gel, 4-fold higher than that of ordinary immobilized cells. A small filter press reactor was constructed to examine the applicability of ethanol fermentation with this forced substrate supply. The operation could be continued for a month at a retention time of 2 h yielding 96 g/l of ethanol from 200 g/l of glucose. 6 references, 5 figures, 3 tables.

Artificial sweeteners

DEFF Research Database (Denmark)

Raben, Anne Birgitte; Richelsen, Bjørn

2012-01-01

Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie-containin......Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie......-containing sweeteners. The purpose of this review is to summarize the current evidence on the effect of artificial sweeteners on body weight, appetite, and risk markers for diabetes and CVD in humans....

Brain MR Image Restoration Using an Automatic Trilateral Filter With GPU-Based Acceleration.

Science.gov (United States)

Chang, Herng-Hua; Li, Cheng-Yuan; Gallogly, Audrey Haihong

2018-02-01

Noise reduction in brain magnetic resonance (MR) images has been a challenging and demanding task. This study develops a new trilateral filter that aims to achieve robust and efficient image restoration. Extended from the bilateral filter, the proposed algorithm contains one additional intensity similarity funct-ion, which compensates for the unique characteristics of noise in brain MR images. An entropy function adaptive to intensity variations is introduced to regulate the contributions of the weighting components. To hasten the computation, parallel computing based on the graphics processing unit (GPU) strategy is explored with emphasis on memory allocations and thread distributions. To automate the filtration, image texture feature analysis associated with machine learning is investigated. Among the 98 candidate features, the sequential forward floating selection scheme is employed to acquire the optimal texture features for regularization. Subsequently, a two-stage classifier that consists of support vector machines and artificial neural networks is established to predict the filter parameters for automation. A speedup gain of 757 was reached to process an entire MR image volume of 256 × 256 × 256 pixels, which completed within 0.5 s. Automatic restoration results revealed high accuracy with an ensemble average relative error of 0.53 ± 0.85% in terms of the peak signal-to-noise ratio. This self-regulating trilateral filter outperformed many state-of-the-art noise reduction methods both qualitatively and quantitatively. We believe that this new image restoration algorithm is of potential in many brain MR image processing applications that require expedition and automation.

Filtering Photogrammetric Point Clouds Using Standard LIDAR Filters Towards DTM Generation

Science.gov (United States)

Zhang, Z.; Gerke, M.; Vosselman, G.; Yang, M. Y.

2018-05-01

Digital Terrain Models (DTMs) can be generated from point clouds acquired by laser scanning or photogrammetric dense matching. During the last two decades, much effort has been paid to developing robust filtering algorithms for the airborne laser scanning (ALS) data. With the point cloud quality from dense image matching (DIM) getting better and better, the research question that arises is whether those standard Lidar filters can be used to filter photogrammetric point clouds as well. Experiments are implemented to filter two dense matching point clouds with different noise levels. Results show that the standard Lidar filter is robust to random noise. However, artefacts and blunders in the DIM points often appear due to low contrast or poor texture in the images. Filtering will be erroneous in these locations. Filtering the DIM points pre-processed by a ranking filter will bring higher Type II error (i.e. non-ground points actually labelled as ground points) but much lower Type I error (i.e. bare ground points labelled as non-ground points). Finally, the potential DTM accuracy that can be achieved by DIM points is evaluated. Two DIM point clouds derived by Pix4Dmapper and SURE are compared. On grassland dense matching generates points higher than the true terrain surface, which will result in incorrectly elevated DTMs. The application of the ranking filter leads to a reduced bias in the DTM height, but a slightly increased noise level.

Parametric optimization for floating drum anaerobic bio-digester using Response Surface Methodology and Artificial Neural Network

Directory of Open Access Journals (Sweden)

S. Sathish

2016-12-01

Full Text Available The main purpose of this study to increase the optimal conditions for biogas yield from anaerobic digestion of agricultural waste (Rice Straw using Response Surface Methodology (RSM and Artificial Neural Network (ANN. In the development of predictive models temperature, pH, substrate concentration and agitation time are conceived as model variables. The experimental results show that the liner model terms of temperature, substrate concentration and pH, agitation time have significance of interactive effects (p < 0.05. The results manifest that the optimum process parameters affected on biogas yield increase from the ANN model when compared to RSM model. The ANN model indicates that it is much more accurate and reckons the values of maximum biogas yield when compared to RSM model.

Artificial cognition architectures

CERN Document Server

Crowder, James A; Friess, Shelli A

2013-01-01

The goal of this book is to establish the foundation, principles, theory, and concepts that are the backbone of real, autonomous Artificial Intelligence. Presented here are some basic human intelligence concepts framed for Artificial Intelligence systems. These include concepts like Metacognition and Metamemory, along with architectural constructs for Artificial Intelligence versions of human brain functions like the prefrontal cortex. Also presented are possible hardware and software architectures that lend themselves to learning, reasoning, and self-evolution

Dynamic spin filtering at the Co/Alq3 interface mediated by weakly coupled second layer molecules

Science.gov (United States)

Droghetti, Andrea; Thielen, Philip; Rungger, Ivan; Haag, Norman; Großmann, Nicolas; Stöckl, Johannes; Stadtmüller, Benjamin; Aeschlimann, Martin; Sanvito, Stefano; Cinchetti, Mirko

2016-08-01

Spin filtering at organic-metal interfaces is often determined by the details of the interaction between the organic molecules and the inorganic magnets used as electrodes. Here we demonstrate a spin-filtering mechanism based on the dynamical spin relaxation of the long-living interface states formed by the magnet and weakly physisorbed molecules. We investigate the case of Alq3 on Co and, by combining two-photon photoemission experiments with electronic structure theory, show that the observed long-time spin-dependent electron dynamics is driven by molecules in the second organic layer. The interface states formed by physisorbed molecules are not spin-split, but acquire a spin-dependent lifetime, that is the result of dynamical spin-relaxation driven by the interaction with the Co substrate. Such spin-filtering mechanism has an important role in the injection of spin-polarized carriers across the interface and their successive hopping diffusion into successive molecular layers of molecular spintronics devices.

Artificial limb representation in amputees.

Science.gov (United States)

van den Heiligenberg, Fiona M Z; Orlov, Tanya; Macdonald, Scott N; Duff, Eugene P; Henderson Slater, David; Beckmann, Christian F; Johansen-Berg, Heidi; Culham, Jody C; Makin, Tamar R

2018-05-01

The human brain contains multiple hand-selective areas, in both the sensorimotor and visual systems. Could our brain repurpose neural resources, originally developed for supporting hand function, to represent and control artificial limbs? We studied individuals with congenital or acquired hand-loss (hereafter one-handers) using functional MRI. We show that the more one-handers use an artificial limb (prosthesis) in their everyday life, the stronger visual hand-selective areas in the lateral occipitotemporal cortex respond to prosthesis images. This was found even when one-handers were presented with images of active prostheses that share the functionality of the hand but not necessarily its visual features (e.g. a 'hook' prosthesis). Further, we show that daily prosthesis usage determines large-scale inter-network communication across hand-selective areas. This was demonstrated by increased resting state functional connectivity between visual and sensorimotor hand-selective areas, proportional to the intensiveness of everyday prosthesis usage. Further analysis revealed a 3-fold coupling between prosthesis activity, visuomotor connectivity and usage, suggesting a possible role for the motor system in shaping use-dependent representation in visual hand-selective areas, and/or vice versa. Moreover, able-bodied control participants who routinely observe prosthesis usage (albeit less intensively than the prosthesis users) showed significantly weaker associations between degree of prosthesis observation and visual cortex activity or connectivity. Together, our findings suggest that altered daily motor behaviour facilitates prosthesis-related visual processing and shapes communication across hand-selective areas. This neurophysiological substrate for prosthesis embodiment may inspire rehabilitation approaches to improve usage of existing substitutionary devices and aid implementation of future assistive and augmentative technologies.

Bias aware Kalman filters

DEFF Research Database (Denmark)

Drecourt, J.-P.; Madsen, H.; Rosbjerg, Dan

2006-01-01

This paper reviews two different approaches that have been proposed to tackle the problems of model bias with the Kalman filter: the use of a colored noise model and the implementation of a separate bias filter. Both filters are implemented with and without feedback of the bias into the model state....... The colored noise filter formulation is extended to correct both time correlated and uncorrelated model error components. A more stable version of the separate filter without feedback is presented. The filters are implemented in an ensemble framework using Latin hypercube sampling. The techniques...... are illustrated on a simple one-dimensional groundwater problem. The results show that the presented filters outperform the standard Kalman filter and that the implementations with bias feedback work in more general conditions than the implementations without feedback. 2005 Elsevier Ltd. All rights reserved....

Study of different filters

International Nuclear Information System (INIS)

Cochinal, R.; Rouby, R.

1959-01-01

This note first contains a terminology related to filters and to their operation, and then proposes an overview of general characteristics of filters such as load loss with respect to gas rate, efficiency, and clogging with respect to filter pollution. It also indicates standard aerosols which are generally used, how they are dosed, and how efficiency is determined with a standard aerosol. Then, after a presentation of the filtration principle, this note reports the study of several filters: glass wool, filter papers provided by different companies, Teflon foam, English filters, Teflon wool, sintered Teflonite, quartz wool, polyvinyl chloride foam, synthetic filter, sintered bronze. The third part reports the study of some aerosol and dust separators

Numerical Study on Self-Cleaning Canister Filter With Add-On Filter Cap

Directory of Open Access Journals (Sweden)

Mohammed Akmal Nizam

2017-01-01

Full Text Available Filtration in a turbo machinery system such as a gas turbine will ensure that the air entering the inlet is free from contaminants that could bring damage to the main system. Self-cleaning filter systems for gas turbines are designed for continuously efficient flow filtration. A good filter would be able to maintain its effectiveness over a longer time period, prolonging the duration between filter replacements and providing lower pressure drop over its operating lifetime. With this goal in mind, the current study is focused on the difference in pressure loss of the benchmark Salutary Avenue Self-cleaning filter in comparison to a new design with an add-on filter cap. Geometry for the add-on filter cap will be based from Salutary Avenue Manufacturing Sdn.Bhd. SOLIDWORKS software was used to model the geometry of the filter, while simulation analysis on the flow through the filter was done using Computational Fluid Dynamic (CFD software. The simulations are based on a low velocity condition, in which the parameter for the inlet velocity are set at 0.032 m/s, 0.063 m/s, 0.094 m/s and 0.126 m/s respectively. From the simulation data obtained for the inlet velocities considered, the pressure drop reduction of the modified filter compared to the benchmark was found to be between 7.59% and 30.18%. All in all, the modification of the filter cap produced a lower pressure drop in comparison with the benchmark filter; an improvement of 27.02% for the total pressure drop was obtained.

Nitrogen removal in permeable woodchips filters affected by hydraulic loading rate and woodchips ratio

DEFF Research Database (Denmark)

Bruun, Jacob Druedahl; Kjærgaard, Charlotte; Hoffmann, Carl Christian

2016-01-01

response of mixed reactive media (woodchips-Seashells and woodchips-Filtralite mixtures) at two woodchips ratios (WR) to changes in the hydraulic loading rate (HLR). The tests implied continuous loading of aerated NO3-N spiked artificial drainage water and tritium (3H2O) breakthrough experiments. Flow...... normalized nitrate reduction rates were 0.35-3.97 g N m-3 L-1, corresponding to N- removal efficiencies of 5 to 74% depending on HLR and filter mixtures. At high HLR oxic conditions prevailed, thus N removal was restricted to the immobile domain, controlled by diffusion. At lower HLR, progressively lower...

Laboratory for filter testing

Energy Technology Data Exchange (ETDEWEB)

Paluch, W.

1987-07-01

Filters used for mine draining in brown coal surface mines are tested by the Mine Draining Department of Poltegor. Laboratory tests of new types of filters developed by Poltegor are analyzed. Two types of tests are used: tests of scale filter models and tests of experimental units of new filters. Design and operation of the test stands used for testing mechanical properties and hydraulic properties of filters for coal mines are described: dimensions, pressure fluctuations, hydraulic equipment. Examples of testing large-diameter filters for brown coal mines are discussed.

Classification of physical exercises using a triaxial accelerometer in a smartphone and an artificial neural network

Directory of Open Access Journals (Sweden)

Cakić Nikola

2017-01-01

Full Text Available The prevalence of smartphones and their adequate computer skills can be used for detecting everyday physical exercises. Acquired information on performed exercises can be used in the field of Health Informatics. For identification of particular physical activity a number of sensors and their repositioning during exercises are needed. This paper presents a way to classify the type of exercise using only triaxial built-in accelerometric sensor in the smartphone. The smartphone itself is free to move inside the subject pocket. The problem of using a number of sensors and their repositioning during exercise is solved by raw signal filtering and by defining a set of signal descriptors. Nine characteristic exercises have been analyzed for different programs and levels of exercise. To filter the raw accelerometer signal a low-pass 10-th order Butterworth filter is used. The filtered signals are described in terms of five descriptors which are used to train an artificial neural network (ANN. Classification of the type of exercise is performed using ANN with an error of 0.7%. Some exercises can be performed with only left or right leg. The classification accuracy of proposed approach is tested in a way that the smartphone was always in the subject's right pocket even when the exercise is performed using left leg only.

Simulasi Filter Pasif Dan Perbandingan Unjuk Kerjanya Dengan Filter Aktif Dan Filter Aktif Hibrid Dalam Meredam Harmonisa Pada Induction Furnace

OpenAIRE

Tanoto, Yusak; Limantara, Limboto; Khandy Lestanto, Khristian

2005-01-01

This paper describe about simulation of Passive Filter in analysis to reduce harmonics that happened in a load such as vacuum casting induction furnace 9 kW, 13.8 kVA, 200V, 3 Ph, 50/60 Hz, also gives comparison with Hybrid Active Filter and Active Filter which made satisfaction result on the previous research. The best result achieved on the use of Hybrid Active Filter on %ITHD for 4.27 % and %VTHD for 3.83%, while Active Filter gave on %ITHD for 5.14 % and %VTHD for 3.82%. There ...

Rotation speed measurement for turbine governor: torsion filtering by using Kalman filter

International Nuclear Information System (INIS)

Houry, M.P.; Bourles, H.

1996-01-01

The rotation speed of a turbogenerator is disturbed by its shaft torsion. Obtaining a filtered measure of this speed is a problem of a great practical importance for turbine governor. A good filtering of this speed must meet two requirements: it must cut frequencies of the shaft torsion oscillation and it must not reduce or delay the signal in the pass-band, i.e. at lower frequencies. At Electricite de France, the speed measure is used to set in motion the fast valving system as quickly as possible, after a short circuit close to the unit or rather an islanding. It is difficult to satisfy these two requirements by using conventional filtering methods. The standard solution consists in a first order filter: at Electricite de France, its time constant is equal to 80 ms. We have decided to improve this filtering by designing a new filter which cuts the frequencies of the shaft torsion oscillation without reducing the bandwidth to the speed measure. If one uses conventional methods to obtain a band stop filter, it is easy to obtain the desired magnitude but not a phase near zero in the whole pass-band. Therefore, we have chosen to design the filter by using Kalman'a theory. The measurement noise is modeled as a colored one, generated by a very lightly damped system driven by a while noise. The resulting Kalman filter is an effective band stop filter, whose phase nicely remains near zero in the whole pass-band. The digital simulations we made and the tests we carried out with the Electricite de France Micro Network laboratory show the advantages of the rotation speed filter we designed using Kalman's theory. With the proposed filter, the speed measure filtering is better in terms of reduction and phase shift. the result is that there are less untimely solicitations of the fast valving system. Consequently, this device improves the power systems stability by minimizing the risks of deep perturbations due to a temporary lack of generation and the risks of under-speed loss

Particulate Emissions Control using Advanced Filter Systems: Final Report for Argonne National Laboratory, Corning Inc. and Hyundai Motor Company CRADA Project

Energy Technology Data Exchange (ETDEWEB)

Seong, Hee Je [Argonne National Lab. (ANL), Argonne, IL (United States); Choi, Seungmok [Argonne National Lab. (ANL), Argonne, IL (United States)

2015-10-09

This is a 3-way CRADA project working together with Corning, Inc. and Hyundai Motor Co. (HMC). The project is to understand particulate emissions from gasoline direct-injection engines (GDI) and their physico-chemical properties. In addition, this project focuses on providing fundamental information about filtration and regeneration mechanisms occurring in gasoline particulate filter (GPF) systems. For the work, Corning provides most advanced filter substrates for GPF applications and HMC provides three-way catalyst (TWC) coating services of these filter by way of a catalyst coating company. Then, Argonne National Laboratory characterizes fundamental behaviors of filtration and regeneration processes as well as evaluated TWC functionality for the coated filters. To examine aging impacts on TWC and GPF performance, the research team evaluates gaseous and particulate emissions as well as back-pressure increase with ash loading by using an engine-oil injection system to accelerate ash loading in TWC-coated GPFs.

The dry filter method for passive filtered venting of the containment

International Nuclear Information System (INIS)

Freis, Daniel; Tietsch, Wolfgang; Obenland, Ralf; Kroes, Bert; Martinsteg, Hans

2013-01-01

Filtered Venting is a mitigative emergency measure to protect the containment from pressure failure in case of a severe accident. Filtered vent systems which are based on the Dry Filter Method (DFM) are proven technology, work completely passive, meet all functional requirements and show excellent performance with respect to filter efficiency. With such a system the release of radioactive fission products to the environment can be effectively minimized. Short and long term land contaminations can be avoided. (orig.)

[Artificial intelligence] AI for protection systems

Energy Technology Data Exchange (ETDEWEB)

Aggarwal, R.; Johns, A.

1997-12-31

The reliable operation of large power systems with small stability margins is highly dependent on control systems and protection devices. Progress in the field of microprocessor systems and demanding requirements in respect of the performance of protective relays are the reasons for digital device applications to power system protection. The superiority of numeric protection over its analogue alternatives is attributed to such factors as accurate extraction of the fundamental voltage and current components through filtering, functional benefits resulting from multi-processor design and extensive self-monitoring, etc. However, all these reasons have not led to a major impact on speed, sensitivity and selectivity of primary protective relays, and the gains are only marginal; this is so because conventional digital relays still rely on deterministic signal models and a heuristic approach for decision making, so that only a fraction of the information contained within voltage and current signals as well as knowledge about the plant to be protected is used. The performance of digital relays may be substantially improved if the decision making is based on elements of artificial intelligence (AI). (Author)

Boreal earliest Triassic biotas elucidate globally depauperate hard substrate communities after the end-Permian mass extinction.

Science.gov (United States)

Zatoń, Michał; Niedźwiedzki, Grzegorz; Blom, Henning; Kear, Benjamin P

2016-11-08

The end-Permian mass extinction constituted the most devastating biotic crisis of the Phanerozoic. Its aftermath was characterized by harsh marine conditions incorporating volcanically induced oceanic warming, widespread anoxia and acidification. Bio-productivity accordingly experienced marked fluctuations. In particular, low palaeolatitude hard substrate communities from shallow seas fringing Western Pangaea and the Tethyan Realm were extremely impoverished, being dominated by monogeneric colonies of filter-feeding microconchid tubeworms. Here we present the first equivalent field data for Boreal hard substrate assemblages from the earliest Triassic (Induan) of East Greenland. This region bordered a discrete bio-realm situated at mid-high palaeolatitude (>30°N). Nevertheless, hard substrate biotas were compositionally identical to those from elsewhere, with microconchids encrusting Claraia bivalves and algal buildups on the sea floor. Biostratigraphical correlation further shows that Boreal microconchids underwent progressive tube modification and unique taxic diversification concordant with changing habitats over time. We interpret this as a post-extinction recovery and adaptive radiation sequence that mirrored coeval subequatorial faunas, and thus confirms hard substrate ecosystem depletion as a hallmark of the earliest Triassic interval globally.

Artificial Disc Replacement

Science.gov (United States)

... Spondylolisthesis BLOG FIND A SPECIALIST Treatments Artificial Disc Replacement (ADR) Patient Education Committee Jamie Baisden The disc ... Disc An artificial disc (also called a disc replacement, disc prosthesis or spine arthroplasty device) is a ...

Predicting CYP2C19 Catalytic Parameters for Enantioselective Oxidations Using Artificial Neural Networks and a Chirality Code

Science.gov (United States)

Hartman, Jessica H.; Cothren, Steven D.; Park, Sun-Ha; Yun, Chul-Ho; Darsey, Jerry A.; Miller, Grover P.

2013-01-01

Cytochromes P450 (CYP for isoforms) play a central role in biological processes especially metabolism of chiral molecules; thus, development of computational methods to predict parameters for chiral reactions is important for advancing this field. In this study, we identified the most optimal artificial neural networks using conformation-independent chirality codes to predict CYP2C19 catalytic parameters for enantioselective reactions. Optimization of the neural networks required identifying the most suitable representation of structure among a diverse array of training substrates, normalizing distribution of the corresponding catalytic parameters (kcat, Km, and kcat/Km), and determining the best topology for networks to make predictions. Among different structural descriptors, the use of partial atomic charges according to the CHelpG scheme and inclusion of hydrogens yielded the most optimal artificial neural networks. Their training also required resolution of poorly distributed output catalytic parameters using a Box-Cox transformation. End point leave-one-out cross correlations of the best neural networks revealed that predictions for individual catalytic parameters (kcat and Km) were more consistent with experimental values than those for catalytic efficiency (kcat/Km). Lastly, neural networks predicted correctly enantioselectivity and comparable catalytic parameters measured in this study for previously uncharacterized CYP2C19 substrates, R- and S-propranolol. Taken together, these seminal computational studies for CYP2C19 are the first to predict all catalytic parameters for enantioselective reactions using artificial neural networks and thus provide a foundation for expanding the prediction of cytochrome P450 reactions to chiral drugs, pollutants, and other biologically active compounds. PMID:23673224

In situ study of the growth and degradation processes in tetragonal lysozyme crystals on a silicon substrate by high-resolution X-ray diffractometry

Science.gov (United States)

Kovalchuk, M. V.; Prosekov, P. A.; Marchenkova, M. A.; Blagov, A. E.; D'yakova, Yu. A.; Tereshchenko, E. Yu.; Pisarevskii, Yu. V.; Kondratev, O. A.

2014-09-01

The results of an in situ study of the growth of tetragonal lysozyme crystals by high-resolution X-ray diffractometry are considered. The crystals are grown by the sitting-drop method on crystalline silicon substrates of different types: both on smooth substrates and substrates with artificial surface-relief structures using graphoepitaxy. The crystals are grown in a special hermetically closed crystallization cell, which enables one to obtain images with an optical microscope and perform in situ X-ray diffraction studies in the course of crystal growth. Measurements for lysozyme crystals were carried out in different stages of the crystallization process, including crystal nucleation and growth, developed crystals, the degradation of the crystal structure, and complete destruction.

Plant cell-wall hydrolyzing enzymes from indigenously isolated fungi grown on conventional and novel natural substrates

International Nuclear Information System (INIS)

Kumari, D.; Sohail, M.; Jahangeer, S.; Abideen, Z.; Khan, M.A.

2017-01-01

Fungi elaborate a variety of plant-hydrolyzing enzymes including cellulases, xylanases, pectinases and amylases. Although these enzymes have potential biotechnological applications, their production at industrial level is limited because of higher costs of the purified substrates. Hence, the present study was aimed to explore the novel, natural and cheaper substrates for enzyme production. Indigenously isolated fungal strains of Aspergillus sp. were grown on banana-peels, grapefruit-peels, pomegranate-peels, sugarcane bagasse, Eucalyptus camaldulensis-leaves and shoots of two halophytic plants including Halopyrum mucronatum and Desmostachya bipinnata under solid-state fermentation (SSF) and submerged fermentation (Smf) conditions. The crude enzyme preparation was screened for cellulase (endoglucanase, beta-glucosidase and filter-paperase), hemicellulase (xylanase), pectinase and amylase production. The results revealed that among all investigated enzymes, the xylanase titers were highest using D. bipinnata- shoots and H. mucronatum- shoots as substrates under solid state fermentation conditions, suggesting their exploitation at commercial scale. (author)

Generalized Selection Weighted Vector Filters

Directory of Open Access Journals (Sweden)

Rastislav Lukac

2004-09-01

Full Text Available This paper introduces a class of nonlinear multichannel filters capable of removing impulsive noise in color images. The here-proposed generalized selection weighted vector filter class constitutes a powerful filtering framework for multichannel signal processing. Previously defined multichannel filters such as vector median filter, basic vector directional filter, directional-distance filter, weighted vector median filters, and weighted vector directional filters are treated from a global viewpoint using the proposed framework. Robust order-statistic concepts and increased degree of freedom in filter design make the proposed method attractive for a variety of applications. Introduced multichannel sigmoidal adaptation of the filter parameters and its modifications allow to accommodate the filter parameters to varying signal and noise statistics. Simulation studies reported in this paper indicate that the proposed filter class is computationally attractive, yields excellent performance, and is able to preserve fine details and color information while efficiently suppressing impulsive noise. This paper is an extended version of the paper by Lukac et al. presented at the 2003 IEEE-EURASIP Workshop on Nonlinear Signal and Image Processing (NSIP '03 in Grado, Italy.

Rotation speed measurement for turbine governor: torsion filtering by using Kalman filter

International Nuclear Information System (INIS)

Houry, M.P.; Bourles, H.

1995-11-01

The rotation speed of a turbogenerator is disturbed by its shaft torsion. Obtaining a filtered measure of this sped a problem of a great practical importance for turbine governor. A good filtering of this speed must meet two requirements: it must cut frequencies of the shaft torsion oscillation and it must not reduce or delay the signal in the pass-band. i.e. at lower frequencies. At Electricite de France, the speed measure is used to set in motion the fast valving system as quickly as possible, after a short circuit close to the unit (to contribute to the stability) or after an islanding (to quickly reach a balance with the house load). It is difficult to satisfy these two requirements by using conventional filtering methods. The standard solution consists in a first order filter: at Electricite de France, its time constant is equal to 80 ms; We have decided to improve this filtering by designing a new filter which cuts the frequencies of the shaft torsion oscillation without reducing the bandwidth of the speed measure. If one uses conventional methods to obtain a band-stop filter (for instance a Butterworth, a Chebyshev or an elliptic band-stop filter),it is easy to obtain the desired magnitude but not a phase near zero in the whole pass-band. Therefore, we have chosen to design the filter by using Kalman's theory. The measurement noise is modeled as a colored one, generated by a very lightly damped system driven by a white noise. The resulting Kalman filter is an effective band-stop filter, whose phase nicely remains near zero in the whole pass-band. (authors). 13 refs., 12 figs

Hierarchical faunal filters: An approach to assessing effects of habitat and nonnative species on native fishes

Science.gov (United States)

Quist, M.C.; Rahel, F.J.; Hubert, W.A.

2005-01-01

Understanding factors related to the occurrence of species across multiple spatial and temporal scales is critical to the conservation and management of native fishes, especially for those species at the edge of their natural distribution. We used the concept of hierarchical faunal filters to provide a framework for investigating the influence of habitat characteristics and normative piscivores on the occurrence of 10 native fishes in streams of the North Platte River watershed in Wyoming. Three faunal filters were developed for each species: (i) large-scale biogeographic, (ii) local abiotic, and (iii) biotic. The large-scale biogeographic filter, composed of elevation and stream-size thresholds, was used to determine the boundaries within which each species might be expected to occur. Then, a local abiotic filter (i.e., habitat associations), developed using binary logistic-regression analysis, estimated the probability of occurrence of each species from features such as maximum depth, substrate composition, submergent aquatic vegetation, woody debris, and channel morphology (e.g., amount of pool habitat). Lastly, a biotic faunal filter was developed using binary logistic regression to estimate the probability of occurrence of each species relative to the abundance of nonnative piscivores in a reach. Conceptualising fish assemblages within a framework of hierarchical faunal filters is simple and logical, helps direct conservation and management activities, and provides important information on the ecology of fishes in the western Great Plains of North America. ?? Blackwell Munksgaard, 2004.

Laser-induced breakdown spectroscopy (LIBS) analysis of calcium ions dissolved in water using filter paper substrates: an ideal internal standard for precision improvement.

Science.gov (United States)

Choi, Daewoong; Gong, Yongdeuk; Nam, Sang-Ho; Han, Song-Hee; Yoo, Jonghyun; Lee, Yonghoon

2014-01-01

We report an approach for selecting an internal standard to improve the precision of laser-induced breakdown spectroscopy (LIBS) analysis for determining calcium (Ca) concentration in water. The dissolved Ca(2+) ions were pre-concentrated on filter paper by evaporating water. The filter paper was dried and analyzed using LIBS. By adding strontium chloride to sample solutions and using a Sr II line at 407.771 nm for the intensity normalization of Ca II lines at 393.366 or 396.847 nm, the analysis precision could be significantly improved. The Ca II and Sr II line intensities were mapped across the filter paper, and they showed a strong positive shot-to-shot correlation with the same spatial distribution on the filter paper surface. We applied this analysis approach for the measurement of Ca(2+) in tap, bottled, and ground water samples. The Ca(2+) concentrations determined using LIBS are in good agreement with those obtained from flame atomic absorption spectrometry. Finally, we suggest a homologous relation of the strongest emission lines of period 4 and 5 elements in groups IA and IIA based on their similar electronic structures. Our results indicate that the LIBS can be effectively applied for liquid analysis at the sub-parts per million level with high precision using a simple drying of liquid solutions on filter paper and the use of the correct internal standard elements with the similar valence electronic structure with respect to the analytes of interest.

Optimization of filter loading

International Nuclear Information System (INIS)

Turney, J.H.; Gardiner, D.E.; Sacramento Municipal Utility District, Herald, CA)

1985-01-01

The introduction of 10 CFR Part 61 has created potential difficulties in the disposal of spent cartridge filters. When this report was prepared, Rancho Seco had no method of packaging and disposing of class B or C filters. This work examined methods to minimize the total operating cost of cartridge filters while maintaining them below the class A limit. It was found that by encapsulating filters in cement the filter operating costs could be minimized

Complexity for Artificial Substrates (

NARCIS (Netherlands)

Loke, L.H.L.; Jachowski, N.R.; Bouma, T.J.; Ladle, R.J.; Todd, P.A.

2014-01-01

Physical habitat complexity regulates the structure and function of biological communities, although the mechanisms underlying this relationship remain unclear. Urbanisation, pollution, unsustainable resource exploitation and climate change have resulted in the widespread simplification (and loss)

Filter feeding mechanics of Hypophthalmichthys molitrix regarding porous gill rakers

Science.gov (United States)

Palumbo, David; Bulusu, Kartik V.; Cohen, Karly; Hernandez, Particia; Leftwich, Megan C.; Plesniak, Michael W.

2017-11-01

The silver carp (Hypophthalmichthys molitrix) is a filter-feeding fish known to feed upon algal-growth in lakes, rivers, and aquacultures. The filter-feeding process centers on sponge-like membranes located in the carp's pharynx supported by fused gill rakers (GRs), which can efficiently strain suspended food particles as small as 4 µm without clogging. Guided by the anatomy of the silver carp, scanning electron microscope (SEM) images of GRs, and video of the silver carp feeding, we have hypothesized that the filtration mechanism involves a pump-based biological function to capture food particles within the GRs. Dye visualization experiments were performed on a silver carp cadaver head, an excised GR sample, and on a scaled GR in vitro model - the Artificial Gill Raker (AGR). Measurements are performed for the AGR using laser Doppler velocimetry (LDV) and penetration pressure monitoring with a biologically-inspired pumping mechanism. The role of mucus in the retention and capture of food particles has also been explored through rheological measurements, and further experimentation is planned. Our motivation stems from the potential to develop bioinspired industrial-scale filtration technologies ranging from wastewater treatment to filtration in the food industry. supported by GW Center for Biomimetics and Bioinspired Engineering.

Artificial heart for humanoid robot using coiled SMA actuators

Science.gov (United States)

Potnuru, Akshay; Tadesse, Yonas

2015-03-01

Previously, we have presented the design and characterization of artificial heart using cylindrical shape memory alloy (SMA) actuators for humanoids [1]. The robotic heart was primarily designed to pump a blood-like fluid to parts of the robot such as the face to simulate blushing or anger by the use of elastomeric substrates for the transport of fluids. It can also be used for other applications. In this paper, we present an improved design by using high strain coiled SMAs and a novel pumping mechanism that uses sequential actuation to create peristalsis-like motions, and hence pump the fluid. Various placements of actuators will be investigated with respect to the silicone elastomeric body. This new approach provides a better performance in terms of the fluid volume pumped.

Artificial life and life artificialization in Tron

Directory of Open Access Journals (Sweden)

Carolina Dantas Figueiredo

2012-12-01

Full Text Available Cinema constantly shows the struggle between the men and artificial intelligences. Fiction, and more specifically fiction films, lends itself to explore possibilities asking “what if?”. “What if”, in this case, is related to the eventual rebellion of artificial intelligences, theme explored in the movies Tron (1982 and Tron Legacy (2010 trat portray the conflict between programs and users. The present paper examines these films, observing particularly the possibility programs empowering. Finally, is briefly mentioned the concept of cyborg as a possibility of response to human concerns.

Networks of neuroblastoma cells on porous silicon substrates reveal a small world topology

KAUST Repository

Marinaro, Giovanni; La Rocca, Rosanna; Toma, Andrea; Barberio, Marianna; Cancedda, Laura; Di Fabrizio, Enzo M.; Decuzzi, Paolo C W; Gentile, Francesco T.

2015-01-01

The human brain is a tightly interweaving network of neural cells where the complexity of the network is given by the large number of its constituents and its architecture. The topological structure of neurons in the brain translates into its increased computational capabilities, low energy consumption, and nondeterministic functions, which differentiate human behavior from artificial computational schemes. In this manuscript, we fabricated porous silicon chips with a small pore size ranging from 8 to 75 nm and large fractal dimensions up to Df ∼ 2.8. In culturing neuroblastoma N2A cells on the described substrates, we found that those cells adhere more firmly to and proliferate on the porous surfaces compared to the conventional nominally flat silicon substrates, which were used as controls. More importantly, we observed that N2A cells on the porous substrates create highly clustered, small world topology patterns. We conjecture that neurons with a similar architecture may elaborate information more efficiently than in random or regular grids. Moreover, we hypothesize that systems of neurons on nano-scale geometry evolve in time to form networks in which the propagation of information is maximized. This journal is

A new relative radiometric consistency processing method for change detection based on wavelet transform and a low-pass filter

Institute of Scientific and Technical Information of China (English)

无

2010-01-01

The research purpose of this paper is to show the limitations of the existing radiometric normalization approaches and their disadvantages in change detection of artificial objects by comparing the existing approaches,on the basis of which a preprocessing approach to radiometric consistency,based on wavelet transform and a spatial low-pass filter,has been devised.This approach first separates the high frequency information and low frequency information by wavelet transform.Then,the processing of relative radiometric consistency based on a low-pass filter is conducted on the low frequency parts.After processing,an inverse wavelet transform is conducted to obtain the results image.The experimental results show that this approach can substantially reduce the influence on change detection of linear or nonlinear radiometric differences in multi-temporal images.

Retrievable Vena Cava Filters in Major Trauma Patients: Prevalence of Thrombus Within the Filter

International Nuclear Information System (INIS)

Mahrer, Arie; Zippel, Douglas; Garniek, Alexander; Golan, Gil; Bensaid, Paul; Simon, Daniel; Rimon, Uri

2008-01-01

The purpose of this study was to report the prevalence of thrombus within a retrievable vena cava filter inserted prophylactically in major trauma patients referred for filter extraction. Between November 2002 and August 2005, 80 retrievable inferior vena cava filters (68 Optease and 12 Gunther-Tulip) were inserted into critically injured trauma patients (mean injury severity score 33.5). The filters were inserted within 1 to 6 (mean 2) days of injury. Thirty-seven patients were referred for filter removal (32 with Optease and 5 with Gunther-Tulip). The indwelling time was 7 to 22 (mean 13) days. All patients underwent inferior vena cavography prior to filter removal. There were no insertion-related complications and all filters were successfully deployed. Forty-three (54%) of the 80 patients were not referred for filter removal, as these patients continued to have contraindications to anticoagulation. Thirty-seven patients (46%) were referred for filter removal. In eight of them (22%) a large thrombus was seen within the filters and they were left in place, all with the Optease device. The other 29 filters (36%) were removed uneventfully.We conclude that the relatively high prevalence of intrafilter thrombi with the Optease filter may be explained by either spontaneous thrombus formation or captured emboli.

Physical characteristics of the paper filter and low cafestol content filter coffee brews.

Science.gov (United States)

Rendón, Mery Yovana; Dos Santos Scholz, Maria Brígida; Bragagnolo, Neura

2018-06-01

The results found in the literature concerning the effect of consuming filter coffee brews on increasing the blood cholesterol levels due to the presence of diterpenes, are divergent. Thus the present research evaluated the diterpene (cafestol and kahweol) concentrations in filter coffee brews prepared with paper filters of different sizes, colors and origins (Brazil, Japan, The United States of America, Germany, France and the Netherlands), with and without micro perforations. This is the first study that reports the physical characteristics of paper filter and its importance to obtain filter coffee brew with low cafestol content. Thus, a sample of Catuai cultivar coffee with high cafestol content was roasted to a medium-light degree and used to prepare the brews in a 1:10 ratio (coffee powder to water). The diterpenes were extracted by direct saponification and quantified and identified by HPLC-DAD-MS/MS. The paper filters were physically characterized by measuring their grammage, and the fat permeation rate calculated in order to better understand the differences between the filters which allow one to obtain higher or lower diterpene contents. The cafestol and kahweol concentrations in the brews varied from 1.62 to 2.98 mg/L and from 0.73 to 1.96 mg/L, respectively. The highest cafestol and kahweol concentrations were obtained using paper filters with micro perforations, considering similar sized paper filters. The paper filters showed high fat permeability and grammages between 50.46 and 67.48 g/m 2 . The diterpene retention capacities of the filters produced in the different countries were similar. The results showed that the porosity of the paper filter and the particle size of the ground roasted coffee were determinant factors in obtaining filter coffee brews with lower cafestol contents. Copyright © 2018 Elsevier Ltd. All rights reserved.

Power electronics substrate for direct substrate cooling

Science.gov (United States)

Le, Khiet [Mission Viejo, CA; Ward, Terence G [Redondo Beach, CA; Mann, Brooks S [Redondo Beach, CA; Yankoski, Edward P [Corona, CA; Smith, Gregory S [Woodland Hills, CA

2012-05-01

Systems and apparatus are provided for power electronics substrates adapted for direct substrate cooling. A power electronics substrate comprises a first surface configured to have electrical circuitry disposed thereon, a second surface, and a plurality of physical features on the second surface. The physical features are configured to promote a turbulent boundary layer in a coolant impinged upon the second surface.

Photonic bandpass filter characteristics of multimode SOI waveguides integrated with submicron gratings.

Science.gov (United States)

Sah, Parimal; Das, Bijoy Krishna

2018-03-20

It has been shown that a fundamental mode adiabatically launched into a multimode SOI waveguide with submicron grating offers well-defined flat-top bandpass filter characteristics in transmission. The transmitted spectral bandwidth is controlled by adjusting both waveguide and grating design parameters. The bandwidth is further narrowed down by cascading two gratings with detuned parameters. A semi-analytical model is used to analyze the filter characteristics (1500  nm≤λ≤1650  nm) of the device operating in transverse-electric polarization. The proposed devices were fabricated with an optimized set of design parameters in a SOI substrate with a device layer thickness of 250 nm. The pass bandwidth of waveguide devices integrated with single-stage gratings are measured to be ∼24  nm, whereas the device with two cascaded gratings with slightly detuned periods (ΔΛ=2  nm) exhibits a pass bandwidth down to ∼10  nm.

Contamination due to memory effects in filtered vacuum arc plasma deposition systems

CERN Document Server

Martins, D R; Verdonck, P; Brown, I G

2002-01-01

Thin film synthesis by filtered vacuum arc plasma deposition is a widely used technique with a number of important emerging technological applications. A characteristic feature of the method is that during the deposition process not only is the substrate coated by the plasma, but the plasma gun itself and the magnetic field coil and/or vacuum vessel section constituting the macroparticle filter are also coated to some extent. If then the plasma gun cathode is changed to a new element, there can be a contamination of the subsequent film deposition by sputtering from various parts of the system of the previous coating species. We have experimentally explored this effect and compared our results with theoretical estimates of sputtering from the SRIM (Stopping and Range of Ions in Matter) code. We find film contamination of order 10-4 - 10-3, and the memory of the prior history of the deposition hardware can be relatively long-lasting.

Contamination due to memory effects in filtered vacuum arc plasma deposition systems

International Nuclear Information System (INIS)

Martins, D.R.; Salvadori, M.C.; Verdonck, P.; Brown, I.G.

2002-01-01

Thin film synthesis by filtered vacuum arc plasma deposition is a widely used technique with a number of important emerging technological applications. A characteristic feature of the method is that during the deposition process not only is the substrate coated by the plasma, but the plasma gun itself and the magnetic field coil and/or vacuum vessel section constituting the macroparticle filter are also coated to some extent. If then the plasma gun cathode is changed to a new element, there can be a contamination of the subsequent film deposition by sputtering from various parts of the system of the previous coating species. We have experimentally explored this effect and compared our results with theoretical estimates of sputtering from the stopping and range of ions in matter code. We find film contamination of the order of 10 -4 -10 -3 , and the memory of the prior history of the deposition hardware can be relatively long lasting

Contamination due to memory effects in filtered vacuum arc plasma deposition systems

Energy Technology Data Exchange (ETDEWEB)

Martins, D.R.; Salvadori, M.C.; Verdonck, P.; Brown, I.G.

2002-08-13

Thin film synthesis by filtered vacuum arc plasma deposition is a widely used technique with a number of important emerging technological applications. A characteristic feature of the method is that during the deposition process not only is the substrate coated by the plasma, but the plasma gun itself and the magnetic field coil and/or vacuum vessel section constituting the macroparticle filter are also coated to some extent. If then the plasma gun cathode is changed to a new element, there can be a contamination of the subsequent film deposition by sputtering from various parts of the system of the previous coating species. We have experimentally explored this effect and compared our results with theoretical estimates of sputtering from the SRIM (Stopping and Range of Ions in Matter) code. We find film contamination of order 10-4 - 10-3, and the memory of the prior history of the deposition hardware can be relatively long-lasting.

Coupling analysis of transcutaneous energy transfer coils with planar sandwich structure for a novel artificial anal sphincter

Institute of Scientific and Technical Information of China (English)

Lei KE; Guo-zheng YAN; Sheng YAN; Zhi-wu WANG; Da-sheng LIU

2014-01-01

This paper presents a set of analytical expressions used to determine the coupling coefficient between primary and secondary Litz-wire planar coils used in a transcutaneous energy transfer (TET) system. A TET system has been designed to power a novel elastic scaling artificial anal sphincter system (ES-AASS) for treating severe fecal incontinence (FI), a condition that would benefit from an optimized TET. Expressions that describe the geometrical dimension dependence of self- and mutual inductances of planar coils on a ferrite substrate are provided. The effects of ferrite substrate conductivity, relative permeability, and geometrical dimensions are also considered. To verify these expressions, mutual coupling between planar coils is computed by 3D finite element analysis (FEA), and the proposed expressions show good agreement with numerical results. Different types of planar coils are fabricated with or without ferrite substrate. Measured results for each of the cases are compared with theoretical predictions and FEA solutions. The theoretical results and FEA results are in good agreement with the experimental data.

Design, control, and implementation of LCL-filter-based shunt active power filters

DEFF Research Database (Denmark)

Tang, Yi; Loh, Poh Chiang; Wang, Peng

2011-01-01

This paper concentrates on the design, control and implementation of an LCL-filter-based shunt active power filter (SAPF), which can effectively compensate harmonic currents produced by nonlinear loads in a three-phase three-wire power system. The use of LCL-filter at the output end of SAPF offer......-loop control system, and active damping implemented with fewer current sensors are all addressed here. An analytical design example is finally presented, being supported with experimental results, to verify its effectiveness and practicality.......This paper concentrates on the design, control and implementation of an LCL-filter-based shunt active power filter (SAPF), which can effectively compensate harmonic currents produced by nonlinear loads in a three-phase three-wire power system. The use of LCL-filter at the output end of SAPF offers...

Inorganic UV filters

Directory of Open Access Journals (Sweden)

Eloísa Berbel Manaia

2013-06-01

Full Text Available Nowadays, concern over skin cancer has been growing more and more, especially in tropical countries where the incidence of UVA/B radiation is higher. The correct use of sunscreen is the most efficient way to prevent the development of this disease. The ingredients of sunscreen can be organic and/or inorganic sun filters. Inorganic filters present some advantages over organic filters, such as photostability, non-irritability and broad spectrum protection. Nevertheless, inorganic filters have a whitening effect in sunscreen formulations owing to the high refractive index, decreasing their esthetic appeal. Many techniques have been developed to overcome this problem and among them, the use of nanotechnology stands out. The estimated amount of nanomaterial in use must increase from 2000 tons in 2004 to a projected 58000 tons in 2020. In this context, this article aims to analyze critically both the different features of the production of inorganic filters (synthesis routes proposed in recent years and the permeability, the safety and other characteristics of the new generation of inorganic filters.

A high-transmission liquid-crystal Fabry-Perot infrared filter for electrically tunable spectral imaging detection

Science.gov (United States)

Liu, Zhonglun; Xin, Zhaowei; Long, Huabao; Wei, Dong; Dai, Wanwan; Zhang, Xinyu; Wang, Haiwei; Xie, Changsheng

2018-02-01

Previous studies have presented the usefulness of typical liquid-crystal Fabry-Perot (LC-FP) infrared filters for spectral imaging detection. Yet, their infrared transmission performances still remain to improve or even rise. In this paper, we propose a new type of electrically tunable LC-FP infrared filter to solve the problem above. The key component of the device is a FP resonant cavity composed of two parallel plane mirrors, in which the zinc selenide (ZnSe) materials with a very high transmittance in the mid-long-wavelength infrared regions are used as the electrode substrates and a layer of nano-aluminum (Al) film, which is directly contacted with liquid-crystal materials, is chosen to make high reflective mirrors as well as the electrodes. Particularly, it should be noted that the directional layer made up of ployimide (PI) used previously is removed. The experiment results indicate that the filter can reduce the absorption of infrared wave remarkably, and thus highlight a road to effectively improve the infrared transmittance ability.

Particle Kalman Filtering: A Nonlinear Framework for Ensemble Kalman Filters

KAUST Repository

Hoteit, Ibrahim

2010-09-19

Optimal nonlinear filtering consists of sequentially determining the conditional probability distribution functions (pdf) of the system state, given the information of the dynamical and measurement processes and the previous measurements. Once the pdfs are obtained, one can determine different estimates, for instance, the minimum variance estimate, or the maximum a posteriori estimate, of the system state. It can be shown that, many filters, including the Kalman filter (KF) and the particle filter (PF), can be derived based on this sequential Bayesian estimation framework. In this contribution, we present a Gaussian mixture‐based framework, called the particle Kalman filter (PKF), and discuss how the different EnKF methods can be derived as simplified variants of the PKF. We also discuss approaches to reducing the computational burden of the PKF in order to make it suitable for complex geosciences applications. We use the strongly nonlinear Lorenz‐96 model to illustrate the performance of the PKF.

Frequency-time behavior of artificially stimulated vlf emissions

International Nuclear Information System (INIS)

Stiles, G.S.; Helliwell, R.A.

1975-01-01

Artificially stimulated VLF emissions (ASE's) are emissions triggered in the magnetosphere by the whistler mode signals from VLF transmitters. These emissions may be separated into two classes, rising and falling, depending on whether the final value of df/dt is positive or negative. Several hundred ASE's triggered by three transmitters have been analyzed using the fast Fourier transform with a filter spacing of 25 Hz and an effective filter width of about 45 Hz. The study was limited to the initial frequency-time behavior of ASE's. Averages taken over many events reveal that both rising and falling tones show the same initial behavior. The emissions begin at the frequency of the triggering signal. Both tones initially rise in frequency, falling tones reversing slope at a point 25--300 Hz above the triggering signal. The slope of rising tones, particularly those triggered by NAA, often abruptly levels off in this same frequency range; as a result, a short (approximately 40 ms) plateau is formed that precedes the final rising phase. The initial frequency offset commonly observed in individual events appears to result from the frequent coincidence with this plateau of a peak in amplitude. Emissions stimulated by all three transmitters show essentially the same features; this finding indicates that their frequency behavior does not depend strongly on transmitter power. The process appears to be asymmetric in frequency; no evidence of initial growth below the triggering frequency has been found. (U.S.)

Application of Artificial Neural Networks to Ship Detection from X-Band Kompsat-5 Imagery

Directory of Open Access Journals (Sweden)

Jeong-In Hwang

2017-09-01

Full Text Available For ship detection, X-band synthetic aperture radar (SAR imagery provides very useful data, in that ship targets look much brighter than surrounding sea clutter due to the corner-reflection effect. However, there are many phenomena which bring out false detection in the SAR image, such as noise of background, ghost phenomena, side-lobe effects and so on. Therefore, when ship-detection algorithms are carried out, we should consider these effects and mitigate them to acquire a better result. In this paper, we propose an efficient method to detect ship targets from X-band Kompsat-5 SAR imagery using the artificial neural network (ANN. The method produces the ship-probability map using ANN, and then detects ships from the ship-probability map by using a threshold value. For the purpose of getting an improved ship detection, we strived to produce optimal input layers used for ANN. In order to reduce phenomena related to the false detections, the non-local (NL-means filter and median filter were utilized. The NL-means filter effectively reduced noise on SAR imagery without smoothing edges of the objects, and the median filter was used to remove ship targets in SAR imagery. Through the filtering approaches, we generated two input layers from a Kompsat-5 SAR image, and created a ship-probability map via ANN from the two input layers. When the threshold value of 0.67 was imposed on the ship-probability map, the result of ship detection from the ship-probability map was a 93.9% recall, 98.7% precision and 6.1% false alarm rate. Therefore, the proposed method was successfully applied to the ship detection from the Kompsat-5 SAR image.

Conceptual model of a logical system processor of selection to electrical filters for correction of harmonics in low voltage lines

Science.gov (United States)

Lastre, Arlys; Torriente, Ives; Méndez, Erik F.; Cordovés, Alexis

2017-06-01

In the present investigation, the authors propose a conceptual model for the analysis and the decision making of the corrective models to use in the mitigation of the harmonic distortion. The authors considered the setting of conventional models, and such adaptive models like the filters incorporation to networks neuronal artificial (RNA's) for the mitigating effect. In addition to the present work is a showing of the experimental model that learns by means of a flowchart denoting the need to use artificial intelligence skills for the exposition of the proposed model. The other aspect considered and analyzed are the adaptability and usage of the same, considering a local reference of the laws and lineaments of energy quality that demands the Department of Electricity and Energy Renewable (MEER) of Equator.

Evidence-Based Evaluation of Inferior Vena Cava Filter Complications Based on Filter Type

Science.gov (United States)

Deso, Steven E.; Idakoji, Ibrahim A.; Kuo, William T.

2016-01-01

Many inferior vena cava (IVC) filter types, along with their specific risks and complications, are not recognized. The purpose of this study was to evaluate the various FDA-approved IVC filter types to determine device-specific risks, as a way to help identify patients who may benefit from ongoing follow-up versus prompt filter retrieval. An evidence-based electronic search (FDA Premarket Notification, MEDLINE, FDA MAUDE) was performed to identify all IVC filter types and device-specific complications from 1980 to 2014. Twenty-three IVC filter types (14 retrievable, 9 permanent) were identified. The devices were categorized as follows: conical (n = 14), conical with umbrella (n = 1), conical with cylindrical element (n = 2), biconical with cylindrical element (n = 2), helical (n = 1), spiral (n = 1), and complex (n = 1). Purely conical filters were associated with the highest reported risks of penetration (90–100%). Filters with cylindrical or umbrella elements were associated with the highest reported risk of IVC thrombosis (30–50%). Conical Bard filters were associated with the highest reported risks of fracture (40%). The various FDA-approved IVC filter types were evaluated for device-specific complications based on best current evidence. This information can be used to guide and optimize clinical management in patients with indwelling IVC filters. PMID:27247477

Substrate use of Pseudovibrio sp. growing in ultra-oligotrophic seawater.

Directory of Open Access Journals (Sweden)

Anne Schwedt

Full Text Available Marine planktonic bacteria often live in habitats with extremely low concentrations of dissolved organic matter (DOM. To study the use of trace amounts of DOM by the facultatively oligotrophic Pseudovibrio sp. FO-BEG1, we investigated the composition of artificial and natural seawater before and after growth. We determined the concentrations of dissolved organic carbon (DOC, total dissolved nitrogen (TDN, free and hydrolysable amino acids, and the molecular composition of DOM by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS. The DOC concentration of the artificial seawater we used for cultivation was 4.4 μmol C L(-1, which was eight times lower compared to the natural oligotrophic seawater we used for parallel experiments (36 μmol C L(-1. During the three-week duration of the experiment, cell numbers increased from 40 cells mL(-1 to 2x10(4 cells mL(-1 in artificial and to 3x10(5 cells mL(-1 in natural seawater. No nitrogen fixation and minor CO2 fixation (< 1% of cellular carbon was observed. Our data show that in both media, amino acids were not the main substrate for growth. Instead, FT-ICR-MS analysis revealed usage of a variety of different dissolved organic molecules, belonging to a wide range of chemical compound groups, also containing nitrogen. The present study shows that marine heterotrophic bacteria are able to proliferate with even lower DOC concentrations than available in natural ultra-oligotrophic seawater, using unexpected organic compounds to fuel their energy, carbon and nitrogen requirements.

Research of process of filtration of salt water by bulk filters with the use of vibration

Directory of Open Access Journals (Sweden)

A. I. Krikun

2018-01-01

Full Text Available For the purification of process water from impurities at fish processing plants, a large number of filtering devices are currently used, differing in their design parameters (mesh, woven, disco, etc.. However, in practice, these filtering devices are mainly used as the first stage of water treatment, since they can not provide sufficient quality of the filtrate. The most effective, as numerous studies of scientists of our country and the world show, are bulk granular filters. Their main advantages over other devices of similar designation are: they have a simple and reliable design; resistant to aggressive operating conditions; they are capable of effectively purifying seawater from mechanical impurities at relatively low pressure; most economical; have a filtering load capable of a long time to work without regeneration (the approximate service life of a grain-loading is 3 to 5 years etc. In this article, the influence of vibration effects on the filtration of sea water in a designed and fabricated filter unit with bulk granular materials of natural and artificial origin, the design of which is protected by two patents for the utility model. The results of the study are presented, revealing the degree of influence of the intensity of vibration of the perforated partitioning wall on the state of bulk granular materials located on it (segregation by size, stratified vibro-packing, compacting or loosening of a layer of granular material. The dependences of the capacity of the filtration unit on the amplitude, frequency and the vibration intensity factor have been experimentally established, which made it possible to establish rational vibration parameters of the perforated septum, under which the filtering layer becomes denser, the porosity of the loading decreases, and the precipitate does not break into the filtrate.

Higher safety and saving of filter material with multi-way sorption filters

International Nuclear Information System (INIS)

Ohlmeyer, M.; Benzel, M.

1978-01-01

The multi-way filter 'Nuclear Karlsruhe' satisfies the requirements of operational safety, high utilisation of the filter material and low pressure drop. An important factor contributing to increased operational safety is due to the fact that the nearly total utilisation of the filter material eliminates the need for optimisation weighing costs against safety. The reduction in filter material consumption reduces not only the direct procurement costs but also the costs of nuclear plants, is radioactive. This contributes in several respects towards a better protection of the environment. The MWS filter can also be used, and presents the same advantages, in non-nuclear plants. (orig.) [de

A field study of physico-chemical states of artificial radionuclides in seawater

International Nuclear Information System (INIS)

Nagaya, Yutaka; Nakamura, Kiyoshi

1974-01-01

The physico-chemical states of artificial radionuclides, 90 Sr, 137 Cs and 144 Ce in seawater were investigated by radiochemical analysis of filtered and unfiltered seawater. The difference of radionuclide concentrations between unfiltered and filtered seawaters was defined as the ''particulate form'' radioisotope and its ''particle ratio'' was discussed. Practically no particulate 90 Sr, greater than 0.22 μ in size, was observed in both coastal and open seawaters, but some of 137 Cs seemed to be insoluble in some circumstances, especially in coastal waters. A considerable amount of 144 Ce was found to be particulate. An estimation of the radionuclides in particulate form was made for Kashima-nada seawaters collected in 1970 to 1972, and it was shown that the possible occurrence of particulate radionuclides, greater than 0.22 μ in size, were 1% or less for 90 Sr and 6% for 137 Cs. In the coastal water, 80% of 144 Ce were seemed to be in particulate form, but in the open seawater only a few %. The influences of suspended materials to 137 Cs and 144 Ce concentration levels in seawater were not negligible and further investigations are desirable. (auth.)

Abundance of non-native crabs in intertidal habitats of New England with natural and artificial structure.

Science.gov (United States)

Lovely, Christina M; O'Connor, Nancy J; Judge, Michael L

2015-01-01

Marine habitats containing complex physical structure (e.g., crevices) can provide shelter from predation for benthic invertebrates. To examine effects of natural and artificial structure on the abundance of intertidal juvenile crabs, 2 experiments were conducted in Kingston Bay, Massachusetts, USA, from July to September, 2012. In the first experiment, structure was manipulated in a two-factor design that was placed in the high intertidal for 3 one-week periods to test for both substrate type (sand vs. rock) and the presence or absence of artificial structure (mesh grow-out bags used in aquaculture, ∼0.5 m(2) with 62 mm(2) mesh openings). The Asian shore crab, Hemigrapsus sanguineus, and small individuals of the green crab, Carcinus maenas, were observed only in the treatments of rocks and mesh bag plus rocks. Most green crabs were small (<6 mm in carapace width) whereas H. sanguineus occurred in a wide range of sizes. In the second experiment, 3 levels of oyster-shell treatments were established using grow-out bags placed on a muddy sand substrate in the low intertidal zone: mesh grow-out bags without shells, grow-out bags with oyster shells, and grow-out bags containing live oysters. Replicate bags were deployed weekly for 7 weeks in a randomized complete block design. All crabs collected in the bags were juvenile C. maenas (1-15 mm carapace width), and numbers of crabs differed 6-fold among treatments, with most crabs present in bags with live oysters (29.5 ± 10.6 m(-2) [mean ± S.D.]) and fewest in bags without shells (4.9 ± 3.7 m(-2)). Both C. maenas and H. sanguineus occurred in habitats with natural structure (cobble rocks). The attraction of juvenile C. maenas to artificial structure consisting of plastic mesh bags containing both oyster shells and living oysters could potentially impact oyster aquaculture operations.

Combination of Wiener filtering and singular value decomposition filtering for volume imaging PET

International Nuclear Information System (INIS)

Shao, L.; Lewitt, R.M.; Karp, J.S.

1995-01-01

Although the three-dimensional (3D) multi-slice rebinning (MSRB) algorithm in PET is fast and practical, and provides an accurate reconstruction, the MSRB image, in general, suffers from the noise amplified by its singular value decomposition (SVD) filtering operation in the axial direction. Their aim in this study is to combine the use of the Wiener filter (WF) with the SVD to decrease the noise and improve the image quality. The SVD filtering ''deconvolves'' the spatially variant axial response function while the WF suppresses the noise and reduces the blurring not modeled by the axial SVD filter but included in the system modulation transfer function. Therefore, the synthesis of these two techniques combines the advantages of both filters. The authors applied this approach to the volume imaging HEAD PENN-PET brain scanner with an axial extent of 256 mm. This combined filter was evaluated in terms of spatial resolution, image contrast, and signal-to-noise ratio with several phantoms, such as a cold sphere phantom and 3D brain phantom. Specifically, the authors studied both the SVD filter with an axial Wiener filter and the SVD filter with a 3D Wiener filter, and compared the filtered images to those from the 3D reprojection (3DRP) reconstruction algorithm. Their results indicate that the Wiener filter increases the signal-to-noise ratio and also improves the contrast. For the MSRB images of the 3D brain phantom, after 3D WF, both the Gray/White and Gray/Ventricle ratios were improved from 1.8 to 2.8 and 2.1 to 4.1, respectively. In addition, the image quality with the MSRB algorithm is close to that of the 3DRP algorithm with 3D WF applied to both image reconstructions

A Hybrid Circuit for Spoof Surface Plasmons and Spatial Waveguide Modes to Reach Controllable Band-Pass Filters.

Science.gov (United States)

Zhang, Qian; Zhang, Hao Chi; Wu, Han; Cui, Tie Jun

2015-11-10

We propose a hybrid circuit for spoof surface plasmon polaritons (SPPs) and spatial waveguide modes to develop new microwave devices. The hybrid circuit includes a spoof SPP waveguide made of two anti-symmetric corrugated metallic strips and a traditional substrate integrated waveguide (SIW). From dispersion relations, we show that the electromagnetic waves only can propagate through the hybrid circuit when the operating frequency is less than the cut-off frequency of the SPP waveguide and greater than the cut-off frequency of SIW, generating efficient band-pass filters. We demonstrate that the pass band is controllable in a large range by designing the geometrical parameters of SPP waveguide and SIW. Full-wave simulations are provided to show the large adjustability of filters, including ultra wideband and narrowband filters. We fabricate a sample of the new hybrid device in the microwave frequencies, and measurement results have excellent agreements to numerical simulations, demonstrating excellent filtering characteristics such as low loss, high efficiency, and good square ratio. The proposed hybrid circuit gives important potential to accelerate the development of plasmonic integrated functional devices and circuits in both microwave and terahertz frequencies.

Effect of Different Substrates on the Acceptance of Grafted Larvae in Commercial Honey Bee (Apis Mellifera Queen Rearing

Directory of Open Access Journals (Sweden)

Contreras-Martinez Celia A.

2017-12-01

Full Text Available The need for the increased production of honey bee (Apis mellifera queens has led beekeepers to use different substrates in artificial queen cups where larvae destined to become queens are deposited (grafting. However, not enough scientific evidence exists that indicates that this practice is useful and what substance offers the best results. This study was conducted to determine with the Doolittle queen rearing method the acceptance rate of larvae deposited on different substrates during grafting and to determine if the sugar content and pH of the substrates used affect the acceptance of larvae in cell builder colonies. The evaluated substrates were coconut water, apple nectar, royal jelly, cola soda and distilled water, plus control (without substrate. Grafted larvae of the six treatments were introduced into cell builder colonies and their acceptance verified after 72 h. Apple nectar provided the highest rate of larvae acceptance with 81.06%, followed by cola soda with 62.93%, coconut water with 60.90%, royal jelly with 57.82% and distilled water with 58.99%. The larvae acceptance rates of all substrates were significantly higher than the control, which had an acceptance rate of 47.04%. No significant relationship was found between the sugar content of the substrates and larvae acceptance. However, although not significant, a high negative correlation was found between the substrate pH and the number of accepted larvae (Rho = - 0.90, p = 0.07. These results suggest that the use of liquid acidic substrates during larvae grafting, in particular apple nectar, may increase the production of honey bee queens.

Choosing and using astronomical filters

CERN Document Server

Griffiths, Martin

2014-01-01

As a casual read through any of the major amateur astronomical magazines will demonstrate, there are filters available for all aspects of optical astronomy. This book provides a ready resource on the use of the following filters, among others, for observational astronomy or for imaging: Light pollution filters Planetary filters Solar filters Neutral density filters for Moon observation Deep-sky filters, for such objects as galaxies, nebulae and more Deep-sky objects can be imaged in much greater detail than was possible many years ago. Amateur astronomers can take

A new source difference artificial neural network for enhanced positioning accuracy

International Nuclear Information System (INIS)

Bhatt, Deepak; Aggarwal, Priyanka; Devabhaktuni, Vijay; Bhattacharya, Prabir

2012-01-01

Integrated inertial navigation system (INS) and global positioning system (GPS) units provide reliable navigation solution compared to standalone INS or GPS. Traditional Kalman filter-based INS/GPS integration schemes have several inadequacies related to sensor error model and immunity to noise. Alternatively, multi-layer perceptron (MLP) neural networks with three layers have been implemented to improve the position accuracy of the integrated system. However, MLP neural networks show poor accuracy for low-cost INS because of the large inherent sensor errors. For the first time the paper demonstrates the use of knowledge-based source difference artificial neural network (SDANN) to improve navigation performance of low-cost sensor, with or without external aiding sources. Unlike the conventional MLP or artificial neural networks (ANN), the structure of SDANN consists of two MLP neural networks called the coarse model and the difference model. The coarse model learns the input–output data relationship whereas the difference model adds knowledge to the system and fine-tunes the coarse model output by learning the associated training or estimation error. Our proposed SDANN model illustrated a significant improvement in navigation accuracy of up to 81% over conventional MLP. The results demonstrate that the proposed SDANN method is effective for GPS/INS integration schemes using low-cost inertial sensors, with and without GPS

Robust Ensemble Filtering and Its Relation to Covariance Inflation in the Ensemble Kalman Filter

KAUST Repository

Luo, Xiaodong

2011-12-01

A robust ensemble filtering scheme based on the H∞ filtering theory is proposed. The optimal H∞ filter is derived by minimizing the supremum (or maximum) of a predefined cost function, a criterion different from the minimum variance used in the Kalman filter. By design, the H∞ filter is more robust than the Kalman filter, in the sense that the estimation error in the H∞ filter in general has a finite growth rate with respect to the uncertainties in assimilation, except for a special case that corresponds to the Kalman filter. The original form of the H∞ filter contains global constraints in time, which may be inconvenient for sequential data assimilation problems. Therefore a variant is introduced that solves some time-local constraints instead, and hence it is called the time-local H∞ filter (TLHF). By analogy to the ensemble Kalman filter (EnKF), the concept of ensemble time-local H∞ filter (EnTLHF) is also proposed. The general form of the EnTLHF is outlined, and some of its special cases are discussed. In particular, it is shown that an EnKF with certain covariance inflation is essentially an EnTLHF. In this sense, the EnTLHF provides a general framework for conducting covariance inflation in the EnKF-based methods. Some numerical examples are used to assess the relative robustness of the TLHF–EnTLHF in comparison with the corresponding KF–EnKF method.

[Total artificial heart].

Science.gov (United States)

Antretter, H; Dumfarth, J; Höfer, D

2015-09-01

To date the CardioWest™ total artificial heart is the only clinically available implantable biventricular mechanical replacement for irreversible cardiac failure. This article presents the indications, contraindications, implantation procedere and postoperative treatment. In addition to a overview of the applications of the total artificial heart this article gives a brief presentation of the two patients treated in our department with the CardioWest™. The clinical course, postoperative rehabilitation, device-related complications and control mechanisms are presented. The total artificial heart is a reliable implant for treating critically ill patients with irreversible cardiogenic shock. A bridge to transplantation is feasible with excellent results.

OPTIMIZATION OF ADVANCED FILTER SYSTEMS

Energy Technology Data Exchange (ETDEWEB)

R.A. Newby; G.J. Bruck; M.A. Alvin; T.E. Lippert

1998-04-30

Reliable, maintainable and cost effective hot gas particulate filter technology is critical to the successful commercialization of advanced, coal-fired power generation technologies, such as IGCC and PFBC. In pilot plant testing, the operating reliability of hot gas particulate filters have been periodically compromised by process issues, such as process upsets and difficult ash cake behavior (ash bridging and sintering), and by design issues, such as cantilevered filter elements damaged by ash bridging, or excessively close packing of filtering surfaces resulting in unacceptable pressure drop or filtering surface plugging. This test experience has focused the issues and has helped to define advanced hot gas filter design concepts that offer higher reliability. Westinghouse has identified two advanced ceramic barrier filter concepts that are configured to minimize the possibility of ash bridge formation and to be robust against ash bridges should they occur. The ''inverted candle filter system'' uses arrays of thin-walled, ceramic candle-type filter elements with inside-surface filtering, and contains the filter elements in metal enclosures for complete separation from ash bridges. The ''sheet filter system'' uses ceramic, flat plate filter elements supported from vertical pipe-header arrays that provide geometry that avoids the buildup of ash bridges and allows free fall of the back-pulse released filter cake. The Optimization of Advanced Filter Systems program is being conducted to evaluate these two advanced designs and to ultimately demonstrate one of the concepts in pilot scale. In the Base Contract program, the subject of this report, Westinghouse has developed conceptual designs of the two advanced ceramic barrier filter systems to assess their performance, availability and cost potential, and to identify technical issues that may hinder the commercialization of the technologies. A plan for the Option I, bench

Artificial Intelligence in Astronomy

Science.gov (United States)

Devinney, E. J.; Prša, A.; Guinan, E. F.; Degeorge, M.

2010-12-01

From the perspective (and bias) as Eclipsing Binary researchers, we give a brief overview of the development of Artificial Intelligence (AI) applications, describe major application areas of AI in astronomy, and illustrate the power of an AI approach in an application developed under the EBAI (Eclipsing Binaries via Artificial Intelligence) project, which employs Artificial Neural Network technology for estimating light curve solution parameters of eclipsing binary systems.

Reservoir Modeling by Data Integration via Intermediate Spaces and Artificial Intelligence Tools in MPS Simulation Frameworks

International Nuclear Information System (INIS)

Ahmadi, Rouhollah; Khamehchi, Ehsan

2013-01-01

Conditioning stochastic simulations are very important in many geostatistical applications that call for the introduction of nonlinear and multiple-point data in reservoir modeling. Here, a new methodology is proposed for the incorporation of different data types into multiple-point statistics (MPS) simulation frameworks. Unlike the previous techniques that call for an approximate forward model (filter) for integration of secondary data into geologically constructed models, the proposed approach develops an intermediate space where all the primary and secondary data are easily mapped onto. Definition of the intermediate space, as may be achieved via application of artificial intelligence tools like neural networks and fuzzy inference systems, eliminates the need for using filters as in previous techniques. The applicability of the proposed approach in conditioning MPS simulations to static and geologic data is verified by modeling a real example of discrete fracture networks using conventional well-log data. The training patterns are well reproduced in the realizations, while the model is also consistent with the map of secondary data

Reservoir Modeling by Data Integration via Intermediate Spaces and Artificial Intelligence Tools in MPS Simulation Frameworks

Energy Technology Data Exchange (ETDEWEB)

Ahmadi, Rouhollah, E-mail: rouhollahahmadi@yahoo.com [Amirkabir University of Technology, PhD Student at Reservoir Engineering, Department of Petroleum Engineering (Iran, Islamic Republic of); Khamehchi, Ehsan [Amirkabir University of Technology, Faculty of Petroleum Engineering (Iran, Islamic Republic of)

2013-12-15

Conditioning stochastic simulations are very important in many geostatistical applications that call for the introduction of nonlinear and multiple-point data in reservoir modeling. Here, a new methodology is proposed for the incorporation of different data types into multiple-point statistics (MPS) simulation frameworks. Unlike the previous techniques that call for an approximate forward model (filter) for integration of secondary data into geologically constructed models, the proposed approach develops an intermediate space where all the primary and secondary data are easily mapped onto. Definition of the intermediate space, as may be achieved via application of artificial intelligence tools like neural networks and fuzzy inference systems, eliminates the need for using filters as in previous techniques. The applicability of the proposed approach in conditioning MPS simulations to static and geologic data is verified by modeling a real example of discrete fracture networks using conventional well-log data. The training patterns are well reproduced in the realizations, while the model is also consistent with the map of secondary data.

Generalised Filtering

Directory of Open Access Journals (Sweden)

Karl Friston

2010-01-01

Full Text Available We describe a Bayesian filtering scheme for nonlinear state-space models in continuous time. This scheme is called Generalised Filtering and furnishes posterior (conditional densities on hidden states and unknown parameters generating observed data. Crucially, the scheme operates online, assimilating data to optimize the conditional density on time-varying states and time-invariant parameters. In contrast to Kalman and Particle smoothing, Generalised Filtering does not require a backwards pass. In contrast to variational schemes, it does not assume conditional independence between the states and parameters. Generalised Filtering optimises the conditional density with respect to a free-energy bound on the model's log-evidence. This optimisation uses the generalised motion of hidden states and parameters, under the prior assumption that the motion of the parameters is small. We describe the scheme, present comparative evaluations with a fixed-form variational version, and conclude with an illustrative application to a nonlinear state-space model of brain imaging time-series.

[Preparation of nano-nacre artificial bone].

Science.gov (United States)

Chen, Jian-ting; Tang, Yong-zhi; Zhang, Jian-gang; Wang, Jian-jun; Xiao, Ying

2008-12-01

To assess the improvements in the properties of nano-nacre artificial bone prepared on the basis of nacre/polylactide acid composite artificial bone and its potential for clinical use. The compound of nano-scale nacre powder and poly-D, L-lactide acid (PDLLA) was used to prepare the cylindrical hollow artificial bone, whose properties including raw material powder scale, pore size, porosity and biomechanical characteristics were compared with another artificial bone made of micron-scale nacre powder and PDLLA. Scanning electron microscope showed that the average particle size of the nano-nacre powder was 50.4-/+12.4 nm, and the average pore size of the artificial bone prepared using nano-nacre powder was 215.7-/+77.5 microm, as compared with the particle size of the micron-scale nacre powder of 5.0-/+3.0 microm and the pore size of the resultant artificial bone of 205.1-/+72.0 microm. The porosities of nano-nacre artificial bone and the micron-nacre artificial bone were (65.4-/+2.9)% and (53.4-/+2.2)%, respectively, and the two artificial bones had comparable compressive strength and Young's modulus, but the flexural strength of the nano-nacre artificial bone was lower than that of the micro-nacre artificial bone. The nano-nacre artificial bone allows better biodegradability and possesses appropriate pore size, porosity and biomechanical properties for use as a promising material in bone tissue engineering.

Photoassisted Oxidation of Sulfides Catalyzed by Artificial Metalloenzymes Using Water as an Oxygen Source †

Directory of Open Access Journals (Sweden)

Christian Herrero

2016-12-01

Full Text Available The Mn(TpCPP-Xln10A artificial metalloenzyme, obtained by non-covalent insertion of Mn(III-meso-tetrakis(p-carboxyphenylporphyrin [Mn(TpCPP, 1-Mn] into xylanase 10A from Streptomyces lividans (Xln10A as a host protein, was found able to catalyze the selective photo-induced oxidation of organic substrates in the presence of [RuII(bpy3]2+ as a photosensitizer and [CoIII(NH35Cl]2+ as a sacrificial electron acceptor, using water as oxygen atom source.

Artificial Self-Sufficient P450 in Reversed Micelles

Directory of Open Access Journals (Sweden)

Teruyuki Nagamune

2010-04-01

Full Text Available Cytochrome P450s are heme-containing monooxygenases that require electron transfer proteins for their catalytic activities. They prefer hydrophobic compounds as substrates and it is, therefore, desirable to perform their reactions in non-aqueous media. Reversed micelles can stably encapsulate proteins in nano-scaled water pools in organic solvents. However, in the reversed micellar system, when multiple proteins are involved in a reaction they can be separated into different micelles and it is then difficult to transfer electrons between proteins. We show here that an artificial self-sufficient cytochrome P450, which is an enzymatically crosslinked fusion protein composed of P450 and electron transfer proteins, showed micelle-size dependent catalytic activity in a reversed micellar system. Furthermore, the presence of thermostable alcohol dehydrogenase promoted the P450-catalyzed reaction due to cofactor regeneration.

The biogenic reefs formed by the alien polychaete Hydroides dianthus (Serpulidae, Annelida) favor the polyp stage of Aurelia coerulea (Cnidaria, Scyphozoa) in a coastal artificial lake.

Science.gov (United States)

Dong, Zhijun; Sun, Tingting; Wang, Lei

2018-04-01

Blooms of the moon jellyfish Aurelia coerulea frequently occur in coastal waters. The increased availability of substrates for the settlement and proliferation of polyps due to the expansion of artificial structures in coastal areas has been proposed as a possible contributing factor in jellyfish blooms. This paper investigates whether a marine artificial lake (Fenghuang Lake) provides additional substrates for A. coerulea polyps and contributes to jellyfish blooms. High densities of A. coerulea ephyrae were discovered in this lake, with a mean density of 41 individuals/m 3 and a maximum measured density of 128 individuals/m 3 . Meanwhile, A. coerulea ephyrae were also found in the two emptying channels outside the lake, with a mean density of 13 individuals/m 3 . Underwater surveys revealed that dense colonies of A. coerulea polyps occurred mainly on biogenic reefs formed by a polychaete, which was identified as an invasive serpulid species Hydroides dianthus, based on the phylogenetic analysis of mitochondrial COI gene sequences. Our study highlights the potential modification of habitats by the alien polychaete H. dianthus, which might provide complex benthic habits suitable for the settlement and proliferation of A. coerulea polyps and may contribute to jellyfish blooms in the marine artificial lake and nearby coastal waters. Copyright © 2018 Elsevier Ltd. All rights reserved.

The effect of self-heating on the performance of a tunable filter with embedded windings in a ferrite LTCC package

KAUST Repository

Arabi, Eyad A.; Shamim, Atif

2015-01-01