1,165 research outputs found

    Fabrication of GaN-Based White Light-Emitting Diodes on Yttrium Aluminum Garnet-Polydimethylsiloxane Flexible Substrates

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    This study concerns the characteristics of white GaN-based light-emitting diode (LED) on flexible substrates. The thin film GaN-based blue LEDs were directly transferred from sapphire onto the flexible polydimethylsiloxane (PDMS) substrates by laser lift-off (LLO) process. The PDMS substrates were incorporated 10–40% cerium doped yttrium aluminum garnet phosphor, YAG:Ce3+, and formed the GaN-based white LEDs. The white LEDs prepared by the GaN-based LEDs on the YAG-PDMS substrates reveal one peak at 470 nm corresponding to the emission of the GaN-based LED and a broadband included five weak peaks caused by YAG:Ce3+ phosphors

    Superplastic Forming of SiAlON Ceramics

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66409/1/j.1151-2916.1994.tb04645.x.pd

    Acute aortic dissection mimicking as ureteral calculus

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    AbstractAcute aortic dissection is an uncommon but life-threatening emergency, which is often missed in up to 38% of patients on initial evaluation, and in up to 28% of patients the diagnosis is made at autopsy. Painless aortic dissection has been reported, but is relatively uncommon. The mortality rates are estimated at 50% by 48 hours and increase by 1% per hour if undiagnosed. We report a case of atypical aortic dissection who presented to ER with subtle unspecific renal colicky like pain as a primary symptom, which had made the prompt diagnosis very challenging and difficult

    Data mining of the GAW14 simulated data using rough set theory and tree-based methods

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    Rough set theory and decision trees are data mining methods used for dealing with vagueness and uncertainty. They have been utilized to unearth hidden patterns in complicated datasets collected for industrial processes. The Genetic Analysis Workshop 14 simulated data were generated using a system that implemented multiple correlations among four consequential layers of genetic data (disease-related loci, endophenotypes, phenotypes, and one disease trait). When information of one layer was blocked and uncertainty was created in the correlations among these layers, the correlation between the first and last layers (susceptibility genes and the disease trait in this case), was not easily directly detected. In this study, we proposed a two-stage process that applied rough set theory and decision trees to identify genes susceptible to the disease trait. During the first stage, based on phenotypes of subjects and their parents, decision trees were built to predict trait values. Phenotypes retained in the decision trees were then advanced to the second stage, where rough set theory was applied to discover the minimal subsets of genes associated with the disease trait. For comparison, decision trees were also constructed to map susceptible genes during the second stage. Our results showed that the decision trees of the first stage had accuracy rates of about 99% in predicting the disease trait. The decision trees and rough set theory failed to identify the true disease-related loci

    Prevalence of Dyslipidemia in Patients Receiving Health Checkups: A Hospital-Based Study

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    We used the dataset from one medical center in Taiwan to explore the prevalence of dyslipidemia, which included 2695 subjects receiving private health checkups in 2003-2004. The overall prevalence of hypercholesterolemia was 53.3% in men and 48.2% in women (P = 0.008). The overall prevalence of hypertriglyceridemia was 29.3% in men and 13.7% in women (P < 0.001). The overall prevalence of elevated LDL level was 50.7% in men and 37.9% in women (P < 0.001). The overall prevalence of low HDL level was 47.4% in men and 53% in women (P = 0.004)

    VLSI Implementation of a Cost-Efficient Loeffler-DCT Algorithm with Recursive CORDIC for DCT-Based Encoder

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    This paper presents a low-cost and high-quality; hardware-oriented; two-dimensional discrete cosine transform (2-D DCT) signal analyzer for image and video encoders. In order to reduce memory requirement and improve image quality; a novel Loeffler DCT based on a coordinate rotation digital computer (CORDIC) technique is proposed. In addition; the proposed algorithm is realized by a recursive CORDIC architecture instead of an unfolded CORDIC architecture with approximated scale factors. In the proposed design; a fully pipelined architecture is developed to efficiently increase operating frequency and throughput; and scale factors are implemented by using four hardware-sharing machines for complexity reduction. Thus; the computational complexity can be decreased significantly with only 0.01 dB loss deviated from the optimal image quality of the Loeffler DCT. Experimental results show that the proposed 2-D DCT spectral analyzer not only achieved a superior average peak signal–noise ratio (PSNR) compared to the previous CORDIC-DCT algorithms but also designed cost-efficient architecture for very large scale integration (VLSI) implementation. The proposed design was realized using a UMC 0.18-μm CMOS process with a synthesized gate count of 8.04 k and core area of 75,100 μm2. Its operating frequency was 100 MHz and power consumption was 4.17 mW. Moreover; this work had at least a 64.1% gate count reduction and saved at least 22.5% in power consumption compared to previous designs

    SEARCH AND PURCHASE IN INFORMATION-OVERLOADED RETAIL ELECTRONIC MARKETPLACE: DOES PRICE AND REPUTATIOIN MATTER?

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    This study explores buyers\u27 search and purchase behavior in an information-overloaded retail Electronic Marketplace (EMP). Two instrumental variables, i.e. number of visitors and number of sales for an item, are used to represent buyers\u27 search and purchase behavior. Price and reputation, two of the most frequently researched independent variables in EMP studies, are considered. The relationships between the two IVs and the two DVs are verified when transaction items are of search-type and of experience-type. This study is conducted using field data collected from Taobao (the most dominant retail EMP in China). It is found that reputation has consistent positive relationships with two DVs. Price has negative effects on two DVs. However, it might have no impacts in the case of experience-type items. Conclusively, in information overloaded EMP, reputation always matters in influencing buyers\u27 search and purchase behavior, while price only matters in the case of search-type items

    THE EFFECTS OF FUNGAL MEDIUM ON HATCHING RATE OF BITING MIDGE

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    The little black mosquitos, Forcipomyia taiwana, bite human and become one of the most annoying pests in Taiwan. Recently, the population of F. taiwana increases and invades urban and countryside. In order to effectively prevent the harassment of F. taiwana, develop control strategy is urgent and necessary. Our study found that the fungal medium influenced the length and width of the F. taiwana eggs. It also significantly decreased the hatching rate of F. taiwana. Besides, this artificial diet was more non-toxic and environment-friendly than general chemical pesticides. Thus, this study provided critical information to develop potentially useful bait of F. taiwana in the future

    Calibration of Parshall Flumes with Non-Standard Entrance Transitions

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    The 9-ince and 18-inch Parshall flumes with the throat section installed level with the bottom of an incoming pipe were tested. The measured discharges for given flow depths (free flow) or differences in flow depths (submerged flow) were found to deviate quite significantly fromt he computed standard Parshall flume disharges at both low and high flow rates. New empirical formulats have been developed to take such deviations into account. It is noted that values of the coefficients and exponents contained in the new formulas depend on the throat size of the flume and the slope of the incoming pipe. Calibration curves and tables were prepared for convenient applications of the new formulas
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