• Journal of radiological science and technology
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• v.41 no.4
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• pp.321-327
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• 2018

The purpose of this study is to compare PET imaging performance with Fluorine-18 ($^{18}F$) and Gallium-68 ($^{68}Ga$) for influence of physical properties of PET tracer. Measurement were performed on a Siemens Biograph mCT64 PET/CT scanner using NEMA IEC body phantom and Flangeless Esser PET phantom containing filled with $^{18}F$ and $^{68}Ga$. Emission scan duration(ESD) was set to 1, 2, 3, 4 and 5min/bed for $^{68}Ga$ and 1min/bed for $^{18}F$. The PET image were evaluated in terms of contrast, spatial resolution. Under same condition, The percentage of contrast recovery measured in the phantom ranged from 16.88% to 72.56% for $^{68}Ga$ and from 27.51% to 74.43% for $^{18}F$ and The FWHM value to evaluate spatial resolution was 10.96 mm for $^{68}Ga$ and 9.19 mm for $^{18}F$. For this study, $^{18}F$ produces better image contrast and spatial resolution than $^{68}Ga$ due to higher positron yield and lower positron energy ($^{18}F$: 96.86%, 633.5 keV, $^{68}Ga$: 88.9%, 1899 keV), The physical properties of PET tracer effect on the PET image. $^{68}Ga$ image applying ESD of 3, 4, 5min/bed were showed similar to $^{18}F$ image with ESD of 1min/bed. This study suggests that increasing ESD for acquiring $^{68}Ga$ PET image seem to be similar to $^{18}F$ image.

• Journal of IKEEE
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• v.11 no.1 s.20
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• pp.69-76
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• 2007

This paper presents the design of LVDS (Low-Voltage-Differential-Signaling) transmitter for Gb/s-per-pin operation. The proposed LVDS transmitter is designed using BiCMOS technology, which can be compatible with CMOS technology. To reduce chip area and enhance the robustness of LVDS transmitter, the MOS switches of transmitter are replaced with lateral bipolar transistor. The common emitter current gain($\beta$) of designed bipolar transistor is 20 and the cell size of LVDS transmitter is $0.01mm^2$. Also the proposed LVDS driver is operated at 1.8V and the maximum data rate is 2.8Gb/s approximately In addition, a novel ESD protection circuit is designed to protect the ESD phenomenon. This structure has low latch-up phenomenon by using turn on/off character of P-channel MOSFET and low triggering voltage by N-channel MOSFET in the SCR structure. The triggering voltage and holding voltage are simulated to 2.2V, 1.1V respectively.

• Spatial Information Research
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• v.23 no.3
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• pp.55-65
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• 2015

It was necessary for us to establish a U-City Integrated platform to handle information and to operate the processes in order to solve various social problems in the modern cities and environment. As time has passed, we have confronted to difficulty in handling massive data with limited storage and computing environment and in not satisfying all the new requirements and on time information from the publics. The bigger the cost of the operation of the platform got, the more doubts to keep and invest more to upgrade it arose. Here, we investigated the limitations of the U-city platforms and analyzed the additional requirements and each function of the platform. In order to meet the requirement, we applied new technologies to deal with massive data and suggested the infrastructure of computing environment. We will be expecting the cost decreasing effects and the benefit increasing effects from the enhancement of U-City platform.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.8917-8921
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• 2014

Objective: To observe and compare the effects of multi-patch biopsy under conventional white light imaging endoscopy (C-WLI) and precise targeted biopsy under magnifying narrow-band imaging endoscopy (M-NBI) on the endoscopic submucosal dissection (ESD) of early gastric cancers and intraepithelial neoplasias. Methods: According to the way of selecting biopsy specimens, patients were divided into C-WLI and M-NBI groups, 20 cases. The ESD operations of the 2 groups were compared quantitively. Results: The mean frequency of biopsy in M-NBI group was ($1.00{\pm}0.00$), obviously lower than in the C-WLI group ($4.78{\pm}1.02$) (P<0.01).The average total number of selected biopsy specimens was also fewer ($1.45{\pm}0.12$ and $7.82{\pm}2.22$, respectively, P<0.01). There was no significant difference in the time of determining excision extension, marking time and the time of specimen excision of 2 groups during the ESD (P>0.05), whereas submucosal injection time, mucosal dissection time, stopping bleeding time, wound processing time in the M-NBI group were significantly shorter than in the C-WLI group (P<0.01). Conclusion: Precise targeted biopsy under M-NBI can obviously shorten the time of ESD operation, with small quantity of tissues but high pathological positive rate.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.1
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• pp.77-86
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• 2001

With the growth of the EC(Electronic Commerce), Buying and selling software through the internet are expanded. Among the ESD(Electronic Software Distribution) methods, Buy-first method and TrY-before-bu1 method can not solve the illegal copy problem. Recently developed EL(Electronic License) model solve the illegal copy problem by separating the software and license. But this method also can not support various ways for payment. In this paper we propose the software license management system that is a newly form like ESD model. This system proposes NL(New License) to support various payment methods and SC(Software Charge) to insure that a seller takes the software price. Agent of the proposed system offers scalability to other systems and illegal copy protection function bv managing NL and SC.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.4
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• pp.495-502
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• 2014

Fast recovery diodes (FRDs) were developed using the $p^{{+}{+}}/n^-/n^{{+}{+}}$ epitaxial layers grown by low temperature epitaxy technology. We investigated the effect of electrostatic discharge (ESD) stresses on their electrical and switching properties using current-voltage (I-V) and reverse recovery time analyses. The FRDs presented a high breakdown voltage, >450 V, and a low reverse leakage current, < $10^{-9}$ A. From the temperature dependence of thermal activation energy, the reverse leakage current was dominated by thermal generation-recombination and diffusion, respectively, at low and high temperature regions. By virtue of the abrupt junction and the Pt drive-in for the controlling of carrier lifetime, the soft reverse recovery behavior could be obtained along with a well-controlled reverse recovery time of 21.12 ns. The FRDs exhibited excellent ESD robustness with negligible degradations in the I-V and the reverse recovery characteristics up to ${\pm}5.5$ kV of HBM and ${\pm}3.5$ kV of IEC61000-4-2 shocks. Likewise, transmission line pulse (TLP) analysis reveals that the FRDs can handle the maximum peak pulse current, $I_{pp,max}$, up to 30 A in the forward mode and down to - 24 A in the reverse mode. The robust ESD property can improve the long term reliability of various power applications such as automobile and switching mode power supply.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.7
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• pp.1429-1435
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• 2004

In this work, high performance broadband amplifier MMIC including all the matching and biasing components, and electrostatic discharge (ESD) protection circuit was developed for K/Ka band applications. Therefore, external biasing or matching components were not required for the operation of the MMIC. STO (SrTiO3) capacitors were employed to integrate the DC biasing components on the MMIC, and miniaturized LC parallel ESD protection circuit was integrated on MMIC, which increased ESD breakdown voltage from 10 to 300 V. A pre-matching technique and RC parallel circuit were used for the broadband design of the amplifier MMIC. The amplifier MMIC exhibited good RF performances and good stability in a wide frequency range. The chip size of the MMICs was $1.7{\pm}0.8$ mm2.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.1
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• pp.1-7
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• 2014

A bidirectional transient voltage suppression (TVS) diode consisting of specially designed $p^--n^{{+}+}-p^-$ multi-junctions was developed using low temperature (LT) epitaxy and fabrication processes. Its electrostatic discharge (ESD) performance was investigated using I-V, C-V, and various ESD tests including the human body model (HBM), machine model (MM) and IEC 61000-4-2 (IEC) analysis. The symmetrical structure with very sharp and uniform bidirectional multi-junctions yields good symmetrical I-V behavior over a wide range of operating temperature of 300 K-450 K and low capacitance as 6.9 pF at 1 MHz. In addition, a very thin and heavily doped $n^{{+}+}$ layer enabled I-V curves steep rise after breakdown without snapback phenomenon, then resulted in small dynamic resistance as $0.2{\Omega}$, and leakage current completely suppressed down to pA. Manufactured bidirectional TVS diodes were capable of withstanding ${\pm}4.0$ kV of MM and ${\pm}14$ kV of IEC, and exceeding ${\pm}8$ kV of HBM, while maintaining reliable I-V characteristics. Such an excellent ESD performance of low capacitance and dynamic resistance is attributed to the abruptness and very unique profiles designed very precisely in $p^--n^{{+}+}-p^-$ multi-junctions.

• Journal of IKEEE
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• v.20 no.3
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• pp.295-298
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• 2016

In this paper, we analysed the properties of the conventional ESD protection devices such as SCR, MVSCR, LVTSCR. The electrical characteristics and the turn-on time properties are simulated by Synopsys T-CAD simulator. As the results, the devices have the holding voltages between 2V and 3V, and the trigger voltage of about 20V with SCR, of about 12V with MVSCR, of about 9V with LVTSCR. The results of the simulation for the turn-on time properties are 2.8ns of SCR, 2.2ns of MVSCR, 2.0ns of LVTSCR. Thus, we prove that LVTSCR has the shortest turn-on time. However, the second breakdown currents(It2) of the devices are 7.7A of SCR, 5.5A of MVSCR, 4A of LVTSCR. This different properties have to be adapted by the operation voltages for I/O Clamps.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.2
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• pp.866-874
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• 2014

This study is case study. The purpose of this study is to analysis 'the project of market' connected with ESD in early childhood education and to examine children's meaningful experiences during the process. This study was carried out in the kindergarten in K city, Chunng-Nam. 5-year children of 2 classes were participated. The results of this study concluded as follows: 'The project of market' showed the possibilities of ESD through reconstructing the existing curriculum. In every stage of the project, skills of ESD were included and developed. This project reflected the key concepts of social, environmental, economic areas. This project resulted by integrated curriculum, participatory engagement, multiple instructional methods.