• Journal of radiological science and technology
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• v.35 no.4
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• pp.315-319
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• 2012

The aim of this study was to develop a signal process circuit for a position sensitive avalanche photodiode detector. The circuit parts consisted of amplification, differential and peak/hold circuit. This research was the baseline to develop highly compact radiation detector. The signal was amplified by an amplification chip and its shape was changed in a differential circuit to minimize the pulse tailing. The peak/hold circuit detect the peak of the signal from the differential circuit and hold the amplitude of the peak for data acquisition. In order to test the intrinsic function of the circuit, the input signal was transmitted from a commercial pulse generator.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.26 no.4
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• pp.355-362
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• 2000

Neoplastic growth is characterized by alterations of oncogenes and antioncogenes. The interaction between activated oncogenes and functional deletion of antioncogene appears to be the driving force directing normal cells to uncontrolled growth resulting in tumor. In addition to those genes mentioned, other genes controlling the entry of cells into the cell cycle have recently been implicated in cancer development. The overexpression of the cyclin D1 gene, which has been mapped to 11q13, either by gene rearrangement or amplification has been noted in various malignant tumors. The product of the cyclin D1 gene forms a complex with cyclin-dependent protein kinases(CDK4) that governs a key transition in the cell cycle. The relationships between the overexpression of cyclin D1 assessed by immunihistochemistry and the amplification of the cyclin D1 gene by differential polymerase chain reaction(DPCR) using primers for dopamin D2 receptor gene in 13 cases of squamous cell carcinomas of the oral cavity have been studied. The semiquantitative assay of cyclin D1 amplification has been made by cyclin D1/dopamin D2 receptor(CD/DR) ratio. The results were as follows; 1. In the normal tissue and the tumor, the CD/DR ratios were 0.82 and 1.36 respectively. This implicates 1.65-fold amplification of cyclin D1 gene in tumor compared to that in normal tissue. 2. The tumor tissue which showed overexpression of cyclin D1 by immunohistochemistry revealed 2-fold amplification of cyclin D1 compared to the normal tissue. 3. The tumor tissue which showed mild expression of cyclin D1 by immunihistochemistry revealed 1.7-fold amplification of cyclin D compared to the normal tissue. 4. The cyclin D1 was overexpressed in the tumor tissue at the rate of 38%. Above results suggest that cyclin D1 has close correlation with the development of carcinoma in the oral cavity. But further studies were needed to elucidate the carcinogeneic mechanisms by comparative studies among cyclin D1, pRb and p53.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.356-359
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• 1988

An FET type urea sensing device has been developed using the ISFET and platinum reference electrode and by employing the differential amplification. The performance characteristics of the fabricated sensor show a good linearity in the urea concentration range of $5{\times}10^{-5}$ to $10^{-3}$g/ml and a stable response.

• Korean Journal of Optics and Photonics
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• v.25 no.1
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• pp.44-49
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• 2014

We have analyzed the amplification of a signal wave in the optical parametric interactions of the pump, signal, and idler waves in planar waveguides, with the pump wave being Cerenkov radiation. Based on the coupled-mode theory, we have derived the first-order coupled-mode differential equations for no pump depletion. The equations can easily be solved numerically. The approximate analytical and numerical solutions of the equations show that the signal wave can be amplified parametrically.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.517-520
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• 2002

This paper has been studied Operational Amplification Circuit that has high power specification of 90 W is designed. In the input differential amplifier stage, the current source for circuit bias is designed to protect device from high voltage source. the criving state has the voltage gain more than input differential stage. With temperature compensation design, output stage works stable in different to temperature.

• Journal of the Institute of Convergence Signal Processing
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• v.2 no.1
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• pp.108-112
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• 2001

Heart sound contains rich information regarding the dynamics of the heart and the auscultation has been a first choice of routine procedures for diagnosis of the heart. However, heart sounds captured using a conventional stethoscope are not often loud or clear enough for doctors to precisely classify their characteristics, especially, under the noisy environments of the hospital. A simple auscultation device that removed shortcomings of the conventional stethoscope was constructed in the study. The device employed a polymer based adherent differential output sensor which was on contact with skin through a coupling medium and appropriated electronic circuits for signal amplification and conditioning An ordinary headphone is taken to hear the captured heart sounds and the volume can be adjusted to hear well. It is also possible that the device sends the captured heart sound signals to a PC where the signals are further processed and viualized.

• Journal of Plant Biotechnology
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• v.30 no.4
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• pp.307-313
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• 2003

Fluorescent differential display (FDD) is a method for identifying differentially expressed genes in eukaryotic cells. The mRNA FDD technology works by systematic amplification of the 3' terminal regions of mRNAs. This method involve the reverse transcription using anchored primers designed to bind 5'boundary of the poly A tails, followed by polymerase chain reaction (PCR) amplification with additional upstream primers of arbitrary sequences. The amplified cDNA subpopulations are separated by denaturing polyacrylamide electrophoresis. To identify the genes involved in the development of first trap leaf, we applied a FDD method using mRNAs from leaf base, first trap leaf and flower tissue, respectively. We screened several genes that expressed specifically in first trap leaf. Nucleotide sequence analysis of these genes revealed that these were protease inhibitor (PI), myo-inositol-1-phosphate synthase and lipocalin-type prostaglandin D synthase. Northern blot analysis showed that these genes were expressed specifically in first trap leaf (in vivo and in vitro). FDD could prove to be useful for simultaneous scanning of transcripts from multiple cDNA samples and faster selection of differentially expressed transcripts of interest.

• Molecular & Cellular Toxicology
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• v.1 no.2
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• pp.92-98
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• 2005

DNA microarray analysis of gene expression in toxicogenomics typically requires relatively large amounts of total RNA. This limits the use of DNA microarray when the sample available is small. To confront this limitation, different methods of linear RNA amplification that generate antisense RNA (aRNA) have been optimized for microarray use. The target preparation strategy using amplified RNA in DNA microarray protocol can be divided into direct-incorporation labeling which resulted in cDNA targets (Cy-dye labeled cDNA from aRNA) and indirect-labeling which resulted in cRNA targets (i.e. Cy-dye labeled aRNA), respectively. However, despite the common use of amplified targets (cDNA or cRNA) from aRNAs, no systemic assessment for the use of amplified targets and bias in terms of hybridization performance has been reported. In this investigation, we have compared the hybridization performance of cRNA targets with cDNA targets from aRNA on a 10 K cDNA microarrays. Under optimized hybridization conditions, we found that 43% of outliers from cDNA technique and 86% from the outlier genes were reproducibly detected by both targets hybridization onto cDNA microarray. This suggests that the cRNA labeling method may have a reduced capacity for detecting the differential gene expression when compared to the cDNA target preparation. However, further validation of this discordant result should be pursued to determine which techniques possesses better accuracy in identifying truly differential genes.

• Journal of Korea Soil Environment Society
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• v.5 no.1
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• pp.3-12
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• 2000

The multi-region model, to describe preferential flow, is an equation representing solute transport in soils by dividing soil into numerous pore groups and using the hydraulic properties of the soil. As the model partial differential equation (PDE) is solved numerically with finite difference methods. a modified equivalent partial differential equation(MEPDE) of the partial differential equation of the multi-region model is derived to analyze the accuracy and consistency of the solution of the model PDE and the Von Neumann method is used to analyze the stability of the finite difference scheme. The evaluation obtained from the MEPDE indicated that the finite difference scheme was found to be consistent with the model PDE and had the second order accuracy The stability analysis is performed to analyze the model PDE with the amplification ratio and the phase lag using the Von Neumann method. The amplification ratio of the finite difference scheme gave non-dissipative results with various Peclet numbers and yielded the most high values as the Peclet number was one. The phase lag showed that the frequency component of the finite difference scheme lagged the true solution. From the result of the stability analysis for the model PDE, it is analyzed that the model domain should be discretized in the range of Pe < 1.0 and Cr < 2.0 to obtain the more accurate solution.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.4
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• pp.352-357
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• 2004

This paper studies the errors that associated with particle velocity and intensity in a space. We theoretically derived their bias error and random error. The analysis shows that the more samples do not always guarantee the better results. The random error of the velocity and intensity are increased when we have many samples. The characteristics of the amplification of the random error are analyzed in terms of the sample spacing. The amplification was found to be related to the spatial differential of random noise. The numerical simulations are performed to verify theoretical results.