• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.3
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• pp.75-85
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• 2009

This work proposes a 13b 100MS/s 0.13um CMOS ADC for 3G communication systems such as two-carrier W-CDMA applications simultaneously requiring high resolution, low power, and small size at high speed. The proposed ADC employs a four-step pipeline architecture to optimize power consumption and chip area at the target resolution and sampling rate. Area-efficient high-speed high-resolution gate-bootstrapping circuits are implemented at the sampling switches of the input SHA to maintain signal linearity over the Nyquist rate even at a 1.0V supply operation. The cascode compensation technique on a low-impedance path implemented in the two-stage amplifiers of the SHA and MDAC simultaneously achieves the required operation speed and phase margin with more reduced power consumption than the Miller compensation technique. Low-glitch dynamic latches in sub-ranging flash ADCs reduce kickback-noise referred to the differential input stage of the comparator by isolating the input stage from output nodes to improve system accuracy. The proposed low-noise current and voltage references based on triple negative T.C. circuits are employed on chip with optional off-chip reference voltages. The prototype ADC in a 0.13um 1P8M CMOS technology demonstrates the measured DNL and INL within 0.70LSB and 1.79LSB, respectively. The ADC shows a maximum SNDR of 64.5dB and a maximum SFDR of 78.0dB at 100MS/s, respectively. The ABC with an active die area of $1.22mm^2$ consumes 42.0mW at 100MS/s and a 1.2V supply, corresponding to a FOM of 0.31pJ/conv-step.

• The Korean Journal of Nuclear Medicine
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• v.32 no.2
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• pp.151-160
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• 1998

Purpose: Piccolo et al. advocated the usefulness of $^{99m}Tc$-MDP breast scan in differential diagnosis of breast mass with high accuracy. But there are little or no follow-up studies about it as we know. We studied $^{99m}Tc$-MDP uptake pattern and lesion/background ratio in patients complaining palpable breast lesions to evaluate the clinical usefulness of $^{99m}Tc$-MDP scan. Materials and Methods: Total 34 patients were studied with physical examination, mammo-gram and $^{99m}Tc$-MDP scan prospectively. Anteroposterior and both lateral view of breast were obtained 5 minutes after iv injection of 740 MBq $^{99m}Tc$-MDP. Breast uptake pattern of $^{99m}Tc$-MDP was analyzed by a grade system: 0=no uptake, grade 1=bilateral diffuse uptake, grade 2=asymmetric faint uptake, grade 3=focal hot uptake. 20 cases were pathologically confirmed by excision biopsy or aspiration biopsy. 14 cases were normal in physical examination and mammogram. Results: Pathologic results showed 7 carcinomas, 6 benign solid tumors, and 7 fibrocystic changes. Grade 3 pattern of $^{99m}Tc$-MDP uptake was noted in 4/7 carcinomas, 3/6 benign solid tumors, and 1/7 fibrocystic changes. Grade 2 pattern was 217, 0/7, 3/7 respectively. The average L/B ratio was 1.66 in carcinomas, 1.68 in benign solid masses, 1.20 in fibrocystic diseases, 1.05 in normal patients. L/B ratio was higher in carcinoma and benign mass groups than in fibrocystic change and normal control groups(p=0.005). But there was no statistical difference between L/B ratio of malignant mass group and benign mass group. Conclusion: $^{99m}Tc$-MDP scan is not suitable to routine clinical use for breast mass diagnosis. It might be used in limited conditions when whole body bone scan is planned.

• The Korean Journal of Nuclear Medicine
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• v.28 no.1
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• pp.44-51
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• 1994

It is known that the normal His-Purkinje system provides for nearly synchronous activation of right (RV) and left (LV) ventricles. When His-Purkinje conduction is abnormal, the resulting sequence of ventricular contraction must be correspondingly abnormal. These abnormal mechanical consequences were difficult to demonstrate because of the complexity and the rapidity of it's events. To determine the relationship of the phase changes and the abnormalities of ventricular conduction, we performed phase image analysis of $^{99m}Tc$-RBC gated blood pool scintigrams in patients with intraventricular conduction disturbances (24 complete left bundle branch block (C-LBBB), 15 complete right bundle branch block (C-RBBB), 13 Wolff-Parkinson-White syndrome (WPW), 10 controls). The results were as follows; 1) The ejection fraction (EF), peak ejection rate (PER), and peak filling rate (PFR) of LV in gated blood pool scintigraphy (GBPS) were significantly lower in patients with C-LBBB than in controls ($44.4{\pm}13.9%$ vs $69.9{\pm}4.2%,\;2.48{\pm}0.98$ vs $3.51{\pm}0.62,\;1.76{\pm}0.71$ vs $3.38{\pm}0.92$, respectively, p<0.05). 2) In the phase angle analysis of LV, Standard deviation (SD), width of half maximum of phase angle (FWHM), and range of phase angle were significantly increased in patients with C-LBBB than in controls ($20.6{\pm}18.1$ vs $8.6{\pm}1.8,\;22.5{\pm}9.2$ vs $16.0{\pm}3.9,\;95.7{\pm}31.7$ vs $51.3{\pm}5.4$, respectively, p<0.05). 3) There was no significant difference in EF, PER, PFR between patients with the Wolff-parkinson-White syndrome and controls. 4) Standard deviation and range of phase angle were significantly higher in patients with WPW syndrome than in controls ($10.6{\pm}2.6$ vs $8.6{\pm}1.8$, p<0.05, $69.8{\pm}11.7$ vs $51.3{\pm}5.4$, p<0.001, respectively), however, there was no difference between the two groups in full width of half maximum. 5) Phase image analysis revealed relatively uniform phase across the both ventricles in patients with normal conduction, but markedly delayed phase in the left ventricle of patients with LBBB. 6) In 13 cases of WPW syndrome, the site of preexcitation could be localized in 10 cases (77%) by phase image analysis. Therefore, it can be concluded that phase image analysis can provide an accurate noninvasive method to detect the mechanical consequences of a wide variety of abnormal electrical activation in ventricles.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.361-371
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• 2000

It has been recently reported that 2-bromopropane (2-BP) induces male reproductive toxicity in both human and experimental animals. However, delayed effects of 2-BP on male reproductive system have not been investigated in detail. The present study was conducted to investigate the testicular toxicity of 2-BP and to determine the recovery of normal spermatogenesis in Sprague-Dawley rats. Male rats aged 5 weeks were administered 1,000mg/kg 2-BP by gavage daily for 4 weeks and sacrificed sequentially at 1, 2, 3, 4 and 12 weeks after initiation of 2-BP treatment. Testicular toxicity was evaluated qualitatively by histopathological examinations and quantitatively by reproductive organ weights, spermatid head count, and repopulation index. In the 2-BP treated rats, the body weights was significantly suppressed and the weights of testes and epididymides were also decreased in a time-dependent manner. On histopathological examination, spermatogonia in stages I-VI and preleptotene and leptotene spermatocytes in stages VII-IX were strongly depleted at 1 week of dosing. Spermatogonia were depleted extensively in all spermatogenic stages at 2 weeks. Continuing with the evolution of spermatogenic cycle, zygotene spermatocytes, pachytene spermatocytes, and round spermatids were sequentially depleted at 2, 3, and 4 weeks of dosing due to the depletion of their precursor cells. Vacuolization of Sertoli cells and spermatid retention were also observed at all time points, suggesting that 2-BP induced Sertoli cell dysfunction. At 12 weeks, after 8 weeks recovery, most of the tubules appeared severely atrophic and were lined by Sertoli cells only. Leydig cell hyperplasia in the interstitial tissue was also found. In addition, dramatic reductions in the number of spermatid heads and repopulation index were observed, indicating that 2-BP-induced testicular injury is irreversible. These results indicate that 4 weeks repeated-dose of 1,000mg/kg 2-BP results in a progressive germ cell loss due to the depletion of spermatogonia followed by long-term testicular atrophy in SD rats.

• Korean Journal of Ichthyology
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• v.27 no.4
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• pp.293-299
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• 2015

The feeding experiment was conducted to investigate the effects of one experimental diet (EDP) and five different commercial diets (CEPs) on growth and body composition for juvenile parrot fish, Oplegnathus fasciatus. An EDP was formulated to contain 50% crude protein (CP) from fishmeal, casein, zein and wheat flour and 15% crude lipid (CL) from squid liver oil. Five CEPs for seawater fish were two domestic E commercial diet (DECD) and C commercial diet (DCCD), three imported H commercial diet (IHCD), L commercial diet (ILCD) and O commercial diet (IOCD) containing 53.1~66.6% CP and 10.7~14.6% CL, respectively. Each diet was fed to triplicate groups of juvenile parrot fish initially weighing $1.14{\pm}.01g/fish$ (mean${\pm}$SD) in a flow-through seawater system with a water temperature of $19.0{\sim}25.0^{\circ}C$. Weight gain (WG) and feed efficiency (FE) were significantly greatest in fish fed the DCCD and IOCD; intermediate responses were observed for fish fed the ILCD, while the IECD, IHCD, and the EDP produced the lowest WG and FE values. Survival with no significant difference approached 100% for fish fed the all six diets in this experiment. Whole-body moisture, protein, lipid and ash contents were not affected by the different type of diets. Therefore, type of diets appeared to be important factor in influencing WG and FE of juvenile parrot fish; the best diets for juvenile parrot fish was determined to be the domestic commercial C and the imported commercial O diets containing high protein (61.3, 66.6%) and lipid (14.6, 13.0%) in natural seawater based on highest WG, and FE, respectively. This study indicates that the two commercially formulated diets containing two highest proteins and lipids used in this experiment could be practical diets for juvenile parrot fish; these differences of growth performance between experimental diet and commercial diets may be reason for different dietary protein and lipid levels.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.2
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• pp.21-31
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• 2010

This paper presents a design of PLL and SSCG for reducing the EMI effect at the electronic machinery and tools for DisplayPort application. This system is composed of the essential element of PLL and Charge-Pump2 and Reference Clock Divider to implement the SSCG operation. In this paper, 270MHz/162MHz dual-mode PLL that can provide 10-phase and 1.35GHz/810MHz PLL that can reduce the jitter are designed for 2.7Gbps/162Gbps DisplayPort application. The jitter can be reduced drastically by combining 270MHz/162MHz PLL with 2-stage 5 to 1 serializer and 1.35GHz PLL with 2 to 1 serializer. This paper propose the frequency divider topology which can share the divider between modes and guarantee the 50% duty ratio. And, the output current mismatch can be reduced by using the proposed charge-pump topology. It is implemented using 0.13 um CMOS process and die areas of 270MHz/162MHz PLL and 1.35GHz/810MHz PLL are $650um\;{\times}\;500um$ and $600um\;{\times}\;500um$, respectively. The VCO tuning range of 270 MHz/162 MHz PLL is 330 MHz and the phase noise is -114 dBc/Hz at 1 MHz offset. The measured SSCG down spread amplitude is 0.5% and modulation frequency is 31kHz. The total power consumption is 48mW.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.9
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• pp.25-33
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• 2007

In this paper, the high isolation and wideband 94 GHz MIMIC(Millimeter-wave Monolithic Integrated Circuit) single balanced cascode mixer was designed and fabricated. Also, we designed and fabricated a 3 dB tandem coupler which has a high isolation and wideband characteristic. The single balanced resistive mixer which does not require an external IF balun was designed using the 0.1 ${\mu}m$ InGaAs/InAlAs/GaAs metamorphic HEMT(High Electron Mobility Transistor). The DC characteristics of MHEMT's are 665 mA/mm of drain current density, 691 mS/mm of maximum transconductance. The current gain cut-off frequency($f_T$) is 189 GHz and the maximum oscillation frequency($f_{max}$) is 334 GHz. A 94 GHz single balanced cascode mixer was fabricated using our 0.1 ${\mu}m$ MHEMT MIMIC process. From the measurements, the fabricated couplers showed wideband characteristics. The conversion loss of single balanced cascode mixer was 9.8 dB at an LO power of 10.9 dBm. The LO to RF isolation of single balanced cascode mixer was 29.5 dB at 94 GHz. We obtained in this study a higher LO-RF isolation compared to some other single balanced mixers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.9
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• pp.1185-1193
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• 2006

This study investigated the effects of green tea on the disorders of lipid metabolism, oxidative system and hepatic functions induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), using adult male rats (SD) for 3 weeks. These 36 animals were divided into four groups. TCDD ($50{\mu}g/kg$ BW) was intraperitoneally injected at the beginning of experiment. Green tea powder was added 1% or 3% levels in basal diets respectively. Relative weights of thymus were decreased about one-third of control group, but those of liver, brain and testis were significantly increased in rats treated TCDD. Neutrophill% and lymphocyte% by TCDD treatment was improved by green tea diets. In liver functional enzyme, elevation of glutamic oxaloacetic transaminase (GOT) and alkaline phosphatase (ALP) activities due to TCDD treatment was lowered by green tea diets. The concentrations of serum and liver lipids were significantly increased by TCDD treatment, however, those of serum and liver triglyceride tended to decrease by green tea diets. Fecal lipid excretion was increased in rats fed green tea diets. Especially, fecal total cholesterol level was significantly elevated by 3% green tea diets. The activities of superoxide dismutase (SOD) were increased in rats fed 3% green tea diets. Increment of benzphetamine N-demethylase (BPND) activity by TCDD treatment was declined by 1% green tea diets. These results indicate that green tea can exert improving effects on liver lipid accumulation and unfavorable hepatic functions, and elevate antioxidation.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.702-708
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• 2011

There are considerable areas of wet paddy fields in Korea that requires improvement of its drainage system. In poorly drained sloping paddy fields, upland crops can be damaged by either rainfall or capillary rise of the water table caused by percolating water beneath the upper fields during summertime rainy season. The purpose of this study is to evaluate excess water stress of soybean yield by drainage systems. Four drainage methods namely open ditch, vinyl barrier, pipe drainage and tube bundle were installed within 1-m position at the lower edge of the upper paddy fields. Stress Day Index (SDI) approach was developed to quantify the the cumulative effect of stress imposed on a soybean yield throughout the growing season. SDI was determined from a stress day factor (SD) and a crop susceptibility factor (CS). The stress day factor is a measure degree and duration of stress of the ($SEW_{30}$). The crop susceptibility factor (CS) depends of a given excess water on crop stage. The results showed that SDI used to represent the moisture stress index was most low on the pipe drainage 64.75 compared with the open ditch 355.4, vinyl barrier 271.55 and tube bundle 171.55. Soybean grain yield increased continuously with the rate of 3% in Vinyl Barrier, 32% in Pipe Drainage and 16% in Tube Bundle.

• The Korean Journal of Nuclear Medicine Technology
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• v.23 no.1
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• pp.35-39
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• 2019

Purpose Hepatitis B virus (hepatitis B virus, HBV) infection is a worldwide major public health problem and it is known as a major cause of chronic hepatitis, liver cirrhosis and liver cancer. And serologic tests of hepatitis B virus is essential for diagnosing and treating these diseases. In addition, with the development of molecular diagnostics, the detection of HBV DNA in serum diagnoses HBV infection and is recognized as an important indicator for the antiviral agent treatment response assessment. We performed HBeAg assay using Immunoradiometric assay (IRMA) and Chemiluminescent Microparticle Immunoassay (CMIA) in hepatitis B patients treated with antiviral agents. The detection rate of HBV DNA in serum was measured and compared by RT-PCR (Real Time - Polymerase Chain Reaction) method Materials and Methods HBeAg serum examination and HBV DNA quantification test were conducted on 270 hepatitis B patients undergoing anti-virus treatment after diagnosis of hepatitis B virus infection. Two serologic tests (IRMA, CMIA) with different detection principles were applied for the HBeAg serum test. Serum HBV DNA was quantitatively measured by real-time polymerase chain reaction (RT-PCR) using the Abbott m2000 System. Results The detection rate of HBeAg was 24.1% (65/270) for IRMA and 82.2% (222/270) for CMIA. Detection rate of serum HBV DNA by real-time RT-PCR is 29.3% (79/270). The measured amount of serum HBV DNA concentration is $4.8{\times}10^7{\pm}1.9{\times}10^8IU/mL$($mean{\pm}SD$). The minimum value is 16IU/mL, the maximum value is $1.0{\times}10^9IU/mL$, and the reference value for quantitative detection limit is 15IU/mL. The detection rates and concentrations of HBV DNA by group according to the results of HBeAg serological (IRMA, CMIA)tests were as follows. 1) Group I (IRMA negative, CMIA positive, N = 169), HBV DNA detection rate of 17.7% (30/169), $6.8{\times}10^5{\pm}1.9{\times}10^6IU/mL$ 2) Group II (IRMA positive, CMIA positive, N = 53), HBV DNA detection rate 62.3% (33/53), $1.1{\times}10^8{\pm}2.8{\times}10^8IU/mL$ 3) Group III (IRMA negative, CMIA negative, N = 36), HBV DNA detection rate 36.1% (13/36), $3.0{\times}10^5{\pm}1.1{\times}10^6IU/mL$ 4) Group IV(IRMA positive, CMIA negative, N = 12), HBV DNA detection rate 25% (3/12), $1.3{\times}10^3{\pm}1.1{\times}10^3IU/mL$ Conclusion HBeAg detection rate according to the serological test showed a large difference. This difference is considered for a number of reasons such as characteristics of the Ab used for assay kit and epitope, HBV of genotype. Detection rate and the concentration of the group-specific HBV DNA classified serologic results confirmed the high detection rate and the concentration in Group II (IRMA-positive, CMIA positive, N = 53).