A great effort of the research community is geared towards the creation of an automatic screening system able to promptly detect diabetic retinopathy with the use of fundus cameras. In addition, there are some documen...
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ISBN:
(纸本)9781424418145
A great effort of the research community is geared towards the creation of an automatic screening system able to promptly detect diabetic retinopathy with the use of fundus cameras. In addition, there are some documented approaches for automatically judging the image quality. We propose a new set of features independent of field of view or resolution to describe the morphology of the patient's vessels. Our initial results suggest that these features can be used to estimate the image quality in a time one order of magnitude shorter than previous techniques.
This research developed the moisture-resistance of printed circuit board (PCB) laminate prototypes based on the non-toxic composite materials made from epoxidized linseed oil, melamine polyphosphate, and flax fibers. ...
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ISBN:
(纸本)9781424422722
This research developed the moisture-resistance of printed circuit board (PCB) laminate prototypes based on the non-toxic composite materials made from epoxidized linseed oil, melamine polyphosphate, and flax fibers. One of the key issues associated with using renewable base materials in composites is their sensitivity to moisture. A characterization of the properties of the 'green' printed circuit boards developed in the present study showed that moisture absorption for untreated fiber laminates (4.87% vs. established limit <0.8% for FR4 boards over a 24 hour submersion period) compromised electrical resistance and decreased dielectric breakdown to an unacceptable level. A theoretical model was used to target methods for reducing moisture absorption. Based on this model, we found that reductions in fiber diffusivity and fiber volume fraction substantially reduce composite diffusivity. Through the use of chemical treatment, moisture absorption over a 24 hour time period was reduced from 4.87% to 1.15%, which improved electrical properties. At the end of this study, 15 of 18 PCB property requirements were met, while 3 moisture-critical property targets were narrowly missed.
We report on a novel three-dimensional Si p-n junction that is capable of performing photovoltaic energy conversion. Vertically aligned pores with a very high aspect ratio of ≫ 100 were formed into a p-type Si substra...
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We report on a novel three-dimensional Si p-n junction that is capable of performing photovoltaic energy conversion. Vertically aligned pores with a very high aspect ratio of ≫ 100 were formed into a p-type Si substrate through an electrochemical etching process. A conformal p-n junction was then created in the etched porous silicon region by introducing phosphorous dopants through proximity rapid thermal diffusion. Al electrodes were subsequently evaporated on the front and back sides of the diode to establish electrical contact to the n-type and p-type regions respectively. Typical device structures resulted in highly three-dimensional diodes with pores extending up to 100 μm deep into the bulk Si. Porous films this thick correspond to an effective internal surface area of ∼ 5150 cm 2 /cm 3 . This ultimately makes the device applicable to both inorganic and organic next generation photovoltaics where it is desirable to maximize the amount of interfacing surface to a given photoactive compound. Dark box and illuminated I–V measurements of the device demonstrated successful monolithic integration of a p-n diode and a high internal surface area host matrix.
The identification of reliable peripheral biomarkers for clinical diagnosis, patient prognosis, and biological functional studies would allow for access to biological information currently available only through invas...
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ISBN:
(纸本)9812776087
The identification of reliable peripheral biomarkers for clinical diagnosis, patient prognosis, and biological functional studies would allow for access to biological information currently available only through invasive methods. Traditional approaches have so far considered aspects of tissues and biofluid markers independently. Here we introduce an information theoretic framework for biomarker discovery, integrating biofluid and tissue information. This allows us to identify tissue information in peripheral biofluids. We treat tissue-biofluid interactions as an information channel through functional space using 26 proteomes from 45 different sources to determine quantitatively the correspondence of each biofluid for specific tissues via relative entropy calculation of proteomes mapped onto phenotype, function, and drug space. Next, we identify candidate biofluids and biomarkers responsible for functional information transfer (p
Clustering is the process of discovering groups within multidimensional data, based on similarities, with a minimal, if any, knowledge of their structure. Distributed data clustering is a recent approach to deal with ...
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Clustering is the process of discovering groups within multidimensional data, based on similarities, with a minimal, if any, knowledge of their structure. Distributed data clustering is a recent approach to deal with geographically distributed databases, since traditional clustering methods require centering all databases in a single dataset. Moreover, current privacy requirements in distributed databases demand algorithms with the ability to process clustering securely. Among the unsupervised neural network models, the self-organizing map (SOM) plays a major role. SOM features include information compression while trying to preserve the topological and metric relationship of the primary data space. This paper presents a strategy for efficient cluster analysis in geographically distributed databases using SOM networks. Local datasets relative to database vertical partitions are applied to distinct maps in order to obtain partial views of the existing clusters. Units of each local map are chosen to represent original data and are sent to a central site, which performs a fusion of the partial results. Experimental results are presented for different datasets.
Nanoscale porous silicon waveguides, both on silicon substrates and free-standing membranes, are explored for biosensing applications. Measured detection limits in the nanomolar range are reported for DNA sensing.
Nanoscale porous silicon waveguides, both on silicon substrates and free-standing membranes, are explored for biosensing applications. Measured detection limits in the nanomolar range are reported for DNA sensing.
Development of modern materials, including nanoclusters, cluster assembled materials and metamaterials is among the actual challenges for the development of future nanotechnologies. Here we discuss the peculiarities o...
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Development of modern materials, including nanoclusters, cluster assembled materials and metamaterials is among the actual challenges for the development of future nanotechnologies. Here we discuss the peculiarities of far-field and near-field light scattering by plasmonic nanoparticles, and possible applications of weakly dissipating materials. Over the last few years many peculiarities of light scattering have been found for nanoparticles in the regime of plasmon resonances. Optical excitation of localized plasmons is accompanied by inverse process - transformation of localized resonant plasmons into scattered light. When radiative damping prevails over the dissipative damping, the effects of anomalous light scattering result in sharp giant optical resonances and complicated near-field structure of the Poynting vector field, see e.g. [1-4]. Here we present peculiarities of far-field and near-field light scattering by plasmonic nanoparticles with weak dissipation and anisotropy.
A primary goal of the integrated neural interface project (INIP) is to develop a wireless, implantable device capable of recording neural activity from 100 micromachined electrodes. The heart of this recording system ...
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A primary goal of the integrated neural interface project (INIP) is to develop a wireless, implantable device capable of recording neural activity from 100 micromachined electrodes. The heart of this recording system is a low-power integrated circuit that amplifies 100 weak neural signals, detects spikes with programmable threshold-crossing circuits, and returns these data via digital radio telemetry. The chip receives power, clock, and command signals through a coil-to-coil inductive link. Here we report that the isolated integrated circuit successfully recorded and wirelessly transmitted digitized electrical activity from peripheral nerve and cortex at 15.7 kS/s. The chip also simultaneously performed accurate on-chip spike detection and wirelessly transmitted the spike threshold-crossing data. We also present preliminary successful results from full system integration and packaging.
The breadth of biological data collected in the last decade has far outstripped the methods available to process it. To effectively investigate and explore this abundance of data, novel automated collection and analys...
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The breadth of biological data collected in the last decade has far outstripped the methods available to process it. To effectively investigate and explore this abundance of data, novel automated collection and analysis approaches must be devised. We have developed a new open software framework, the Open Genomic Analysis Platform (OGAP), to aid in the analysis of genomic data. It is capable of analyzing a variety of data source, and focuses on using information theory to characterize data. The frameworks has is capable of import a variety of genome tied data, and provides custom analysis and visualization of results. We then demonstrate the use of this framework analyzing the Prochlorococcus Marinus organism. We show a strong correlation between the information content of sequence data and up regulation of gene expression during lytic infection.
作者:
In Sook KimJongKeun SongYun MiSongTae Hyung LeeTae Hyung ChoShin Saeng LimHui PanSung June KimSoon Jung HwangDental Research Institute
Seoul National UniversityBrain Korea 21 2nd Program for Craniomaxillofacial Life ScienceKorea School of Electrical Engineering and Computer ScienceSeoul National UniversitySeoulKorea Department of Maxillofacial Cell and Developmental BiologyDepartment of Oral and Maxillofacial SurgerySchool of DentistrySeoul National UniversityBrain Korea 21 2nd Program for Craniomaxillofacial Life ScienceSeoulKorea
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