• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.2
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• pp.125-129
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• 2008

A low-voltage active CMOS inductor approach, which can improve the quality-factor(Q), is proposed in this paper. A low-voltage active inductor circuit topology with a feedback resistance is proposed, which can substantially improve its equivalent inductance and quality-factor(Q). This proposed low-voltage active inductor with a feedback resistance was simulated by ADS(Agilent) using 0.18um standard CMOS technology. Simulation showed that the designed active inductor had a maximum quality-factor(Q) of 3000 with a 1.5nH inductance at 4GHz

• Natural Product Sciences
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• v.22 no.3
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• pp.209-215
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• 2016

Kigelia africana (Lam.) Benth. (Bignoniaceae) is a flowering plants in South, Central and West Africa and commonly known as the sausage tree (Eng.); worsboom (Afr.); umVunguta, umFongothi (Zulu); Modukguhlu (North Sotho); Muvevha (Venda). The dried, powdered fruits are used as dressing for wounds and ulcers, haemorrhoids, rheumatism, purgative, skin-firming, lactation in breast-feeding mothers. The aim of this study is to investigate the cytotoxic and apoptotic potentials of 70% ethanolic extracts of Kigelia africana fruits in HCT116 human colon cancer cells. Treatment of Kigelia africana fruits with various concentrations resulted in a sequence of characteristic of apoptosis, including loss of cell viability and morphological changes. Flow cytometry analysis showed Kigelia africana fruits increased the sub-G1 phase (apoptosis) population. Apoptosis confirmed by annexin V-fluorescein isothiocyanate and propidium iodide double staining in HCT116 human colon cancer cell lines. Moreover, analysis of the mechanism indicated that Kigelia africana fruits showed an increased Bax and Bcl-2 expressions in a dose-dependent manner, resulting in activation of hallmarks of apoptotic events, caspase-3, caspase-9 and cleaved poly-ADP-ribose polymerase. This is the first report to demonstrate the cytotoxicity of Kigelia africana fruits on HCT116 human colon cancer cells.

• Journal of Korea Water Resources Association
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• v.31 no.5
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• pp.613-620
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• 1998

Field and laboratory studies of the near field behavior of the San Francisco ocean outfall were reported. The data sets cover broad ranges of discharge conditions and oceanic conditions, and are associated with a typical type of outfall discharges with multiport diffusers. The laboratory data sets were obtained in density-stratified towing tanks to replicate the field tests. Model studies of wastefield behavior using these data sets were predicted by the mathematical models UM, UDKHDEN, RSB, and CORMIX2 for minimum dilution, the height to top of wastefield, and wastefield thickness. In this paper, the results are discussed and compared measurements with mathematical model predictions. The hydraulic model studies reproduced the major features observed in the field. It also afforded considerable insight into the mechanics of mixing of multiport risers which could have been obtained neither from the field test nor the mathematical models.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.779-785
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• 2006

This paper introduces a result of internal signal modeling for a defect diagnosis of the UM-71C track circuit using on HSL. Actually, We fixed a sample area within operating section on HSL and performed the simulations for short circuit current that is reflected characteristic impedance and propagation factor. We compared the measuring data with the result of the simulation. These modeling can be used as the basic data for secure of the safety. Also, It need to make a criteria of analysis for the maintenance through comparison simulation data and inspection data.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.425-428
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• 2011

This paper presents a micro-scale solar energy harvesting circuit with a simple MPPT control. Solar Energy is harvested using a small off-chip PV cell generating output voltages under 0.5V instead of an on-chip PV cell. A simple MPPT is implemented using a pilot PV cell and utilizing the relationship between the open-circuit voltage of a PV cell ($V_{OC}$) and its MPP voltage ($V_{MPP}$). With applying the MPPT control, the designed circuit delivers the MPP voltage to load even though the loads is heavy such that the load circuit can operate properly. The proposed circuit is designed in TSMC 0.18um CMOS process.

• Journal of Korean Medicine for Obesity Research
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• v.7 no.2
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• pp.45-59
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• 2007

Background : There are many korean women who have localized fat despite of they have normal or slightly over weight. The relationships of traditional diagnostic method with total body fat and body mass index had been reviewed in other study, but there is no study regarding the relationship of traditional diagnostic method and localized fat. So we designed this study to find out the relationships between localized fat and traditional diagnostic method among Korean high-school girls. Methods : This research was performed in 21 high-school girls with localized fat during April 2007. We measured body mass index, percent of body fat, waist circumference, hip circumference and means of both thigh circumference. Phlegm questionnaire, blood stasis questionnaire, cold-heat questionnaire, Korean eating attitude test-26 and questionnaire of Sasang constitution classification Ⅱ+ have been administered. Results : There were significant correlations between body mass index, percent of body fat and body size. Regardless of body mass index, they had high phlegm and heat pattern. Most of them are classified as Tae-um type person. Conclusions : High-school girls with localized fat had pattern of high phlegm, heat and characteristics of Tae-um person.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.436-440
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• 2014

The ${\alpha}$-Effect; Ground state; Transition state; Intramolecular H-bonding; Yukawa-Tsuno plot; Second-order rate constants for aminolysis of 2-chloro-4-nitrophenyl X-substituted-benzoates (1a-h) have been measured spectrophotometrically in 80 mol % $H_2O/20$ mol % DMSO at $25.0^{\circ}C$. The Br${\emptyset}$nsted-type plot for the reactions of 2-chloro-4-nitrophenyl benzoate (1d) with a series of primary amines curves downward, which has been taken as evidence for a stepwise mechanism with a change in rate-determining step (RDS). The Hammett plots for the reactions of 1a-h with hydrazine and glycylglycine are nonlinear while the Yukawa-Tsuno plots exhibit excellent linearity with ${\rho}_X=1.22-1.35$ and ${\gamma}= 0.57-0.59$, indicating that the nonlinear Hammett plots are not due to a change in RDS but are caused by stabilization of substrates possessing an electron-donating group (EDG) through resonance interactions between the EDG and C=O bond of the substrates. The ${\alpha}$-effect exhibited by hydrazine increases as the substituent X changes from a strong EDG to a strong electron-withdrawing group (EWG). It has been concluded that destabilization of hydrazine through the electronic repulsion between the adjacent nonbonding electrons is not solely responsible for the substituent dependent ${\alpha}$-effect but stabilization of the transition state is also a plausible origin of the ${\alpha}$-effect.

• The Journal of Korean Medicine
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• v.28 no.1 s.69
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• pp.51-62
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• 2007

Objectives . The types of Sasang constitutional medicine (SCM) have definite effect on response to herbal drugs. The majority of human P45O dependent xenobiotic metabolism is carried out by polymorphic enzymes which can cause abolished, altered or enhanced metabolism. Therefore, we evaluated the relation of major CYP2C19, 2D6 polymorphism with Sasang types. Methods : 214 healthy subjects were recruited with informed consent; 172 among them had Sasang diagnosis by QSCC2. CYP2D6, 2C19 polymorphism were determined by PCR-RFLP method. Results : None of the Sasang types showed significant difference in CYP2D6, 2C19 polymorphism. However, the Tae-um type showed relatively low frequency of CYP2D6 $^{*}$10/$^{*}$10 polymorphisms with low activity (p=0.110). In the So-yang type, specific $^{*}$3/$^{*}$3 genotype which is a poor metabolizer of CYP2C19$^{*}$3 was detected (p=0.078).Conclusion . These results suggest that the Tae-um type which is said to have high liver function in SCM has the tendency of high drug-metabolizing enzyme activity. With further study, the CYP polymorphism could serve as a scientific tool for SCM diagnosis.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.6
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• pp.50-56
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• 2015

An efficient fast response hysteretic buck converter suitable for mobile application is propoesed. The problems of large output ripple and difficulty in using of small power inductor that conventional hysteretic converter has are improved by adding ramp generator. and the changeable switching frequency with load current is fixed by adding a delay time control circuit composed of PLL structure resulting in decrease of EMI noise. The circuits are implemented by using BCDMOS 0.35um 2-polt 4-metal process. Measurement results show that the converter operates with a switching frequency of 1.85MHz when drives 80mA load current. As the converter drives over 170mA load current, the switching frequency is fixed on 2MHz. The converter has output ripple voltage of less 20mV and more than efficiency 85% with 50~500mA laod current condition.

• Proceedings of the KIEE Conference
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• 1999.07f
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• pp.2786-2788
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• 1999

In this paper, a mixed mode exciting resonant inverter topology applicable to high performance electronic ballast is presented. Mixed mode exciting technique combines the attractive features of self exciting resonant inverter with those of external exciting one. The control IC is designed and manufactured by using a 0.8um CMOS process for 5V operation and has only 8 pins. This performs the operations of filament preheating, dimming control, output power regulation and protections. The mixed mode exciting resonant inverter with control IC has very simple structure, high performance and expensive manufacturing cost.