• Archives of Pharmacal Research
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• v.28 no.11
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• pp.1205-1212
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• 2005

2-Thiouracil-5-sulphonic acid N-(4-acetylphenyl) Amide (1) was reacted with a series of aromatic aldehydes giving chalcones 2 (Claisen-Schemidt reaction), some of these chalcones were reacted with urea and thiourea giving pyrimidine-2-one and pyrimidine-2 thione derivatives respectively of the type 3a,b and 4a,b. In addition many chalcones were reacted with hydroxylamine hydrochloride giving isoxazoline derivatives 5a,b. They could also reacted with phenylhydrazine to give pyrazoline derivatives 5a,b, chalcones also were reacted withethylcyano acetate and/or malononitryl in pyridine giving pyran derivatives 7a,c and 8a,c. In another pathway chalcones were epoxidised by $H_{2}O_{2}$ giving epoxides 9a,c which in turn were reacted with phenylhydrazine giving 4-hydroxypyrazoline derivatives 10a,c. In another reaction chalcones were reacted with ethylcyanoacetate in presence of amm.acetate giving pyridone derivatives 11a,d which could be prepared also in exellent yield from compound 1 by its reaction with certain aromatic aldehydes and ethylcyanoacetate in presence of ammonium acetate. Finally, compound 1 was reacted with semicarbazide giving semicarbazone intermediate 12 which in turn was reacted with thionyl chloride giving thiadiazole derivative 13. The biological effects of some of the new synthesized compounds were also investigated.

• Proceedings of the KIEE Conference
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• 1998.07a
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• pp.107-109
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• 1998

This paper presents mechanical analysis of gas turbine generator (113MVA, $3{\phi}$, 2P, 0.9PF, F class, 3600rpm, 60Hz, 13.8kV, 4.72kA, Air-Cooling) field coil deformation. Rotor end coil deformation is only appeared on turbine end but collector end coil is normal. Expansion direction of end coil is tangential not axial. Deformation appears more severe at top turn. Retaining ling is expanded by centrifugal force of coil and itself. In case friction coefficient between coil top surface and retaining ring insulation inner surface is small, coil end length ${\ell}$ does not change. However, in case friction coefficient big condition, coil end is expanded ${\Delta}{\ell}$ due to start and stop. Deformation is assumed about 30mm by watching photograph inner surface of retaining ring is coated by Teflon at manufacturing condition. Usually Teflon coating insulation surface is small friction coefficient. It's value 0.08${\sim}$0.15. However it's value exceeds more than 0.297. Since top turn deformation appears. The distortion and subsequent failure have occurred because of the lack of a sufficient slip-plane between the top field coil conductors and the inside surface of the retaining ring insulation on the turbine end of the field-winding.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.1169-1171
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• 2003

This paper presents a 1.6[kW]class single phase high power factor(HPF) pulse width modulation(PWM) boost rectifier featuring soft commutation of the active switches at zero current. It incorporates the most desirable properties of conventional PWM and soft switching resonant techniques. The input current shaping is achieved with average current mode control and continuous inductor current mode. This new PWM converter provides zero current turn on and turn off of the active switches, and it is suitable for high power applications employing insulated gate bipolar transistors(IGBT'S). The principle of operation, the theoretical analysis, a design example, and experimental results from laboratory prototype rated at 1.6[kW] with 400[Vdc] output voltage are presented. The measured efficiency and the power factor were 96.2[%] and 0.99[%], respectively, with an input current Total Harmonic Distortion(THD) equal to 3.94[%], for an input voltage with THD equal to 3.8[%], at rated load.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.3
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• pp.215-227
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• 2019

Grid-connected inverters should satisfy a certain level of total harmonic distortion (THD) to meet harmonics standards, such as IEEE 519 and P1547. The output quality of an inverter is typically degraded due to grid voltage harmonics, dead time effects, and the device's turn-on/turn-off delay, which all contribute to increasing the THD value of the output. The use of a harmonic controller is essential to meet the required THD value for inverter output under a distorted grid condition. In this study, an improved feedforward harmonic compensation method is proposed to effectively eliminate low-order harmonics in the inverter current to the grid. In the proposed method, harmonic components are directly compensated through feedforward terms generated by the proportional resonant controller with the grid current in a stationary frame. The proposed method is simple to implement but powerful in eliminating harmonics from the output. The effectiveness of the proposed method is verified through simulation using PSIM software and experiments with a 5 kW single-phase grid-connected inverter.

• Molecules and Cells
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• v.21 no.2
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• pp.251-260
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• 2006

During mitosis, genomic integrity is maintained by the proper coordination of anaphase entry and mitotic exit via mitotic checkpoints. In budding yeast, mitotic exit is controlled by a regulatory cascade called the mitotic exit network (MEN). The MEN is regulated by a small GTPase, Tem1p, which in turn is controlled by a two-component GAP, Bfa1p-Bub2p. Recent results suggested that phosphorylation of Bfa1p by the polorelated kinase Cdc5p is also required for triggering mitotic exit, since it decreases the GAP activity of Bfa1p-Bub2p. However, the dispensability of GEF Lte1p for mitotic exit has raised questions about regulation of the MEN by the GTPase activity of Tem1p. We isolated a Bfa1p mutant, $Bfa1p^{E438K}$, whose overexpression only partially induced anaphase arrest. The molecular and biochemical functions of $Bfa1p^{E438K}$ are similar to those of wild type Bfa1p, except for decreased GAP activity. Interestingly, in $BFA1^{E438K}$ cells, the MEN could be regulated with nearly wild type kinetics at physiological temperature, as well as in response to various checkpoint-activating signals, but the cells were more sensitive to spindle damage than wild type. These results suggest that the GAP activity of Bfa1p-Bub2p is responsible for the mitotic arrest caused by spindle damage and Bfa1p overproduction. In addition, the viability of cdc5-2 ${\Delta}bfa1 $ cells was not reduced by $BFA1^{E438K}$, suggesting that Cdc5p also regulates Bfa1p to activate mitotic exit by other mechanism(s), besides phosphorylation.

• Journal of Korean Society of Transportation
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• v.23 no.4 s.82
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• pp.47-55
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• 2005

In recent years, the rapid growth of vehicles have increased traffic crashes. Since they can cause the economic losses and have put the life qualify in danger, there should be numerous efforts to reduce traffic crashes. To reduce traffic crashes, this research seeks to improve the safety of intersections by analysing causations of injury severity with Ordered Probability Model. This research applied the Ordered Probit Model, which assumes that ${\epsilon}_i$(random error) is normally distributed, for model calibration and used $p^2$ (likelihood ratio) and $x^2$ (Chi-square) for model selection. The results show that minor road traffic, heavy vehicle rates, major and minor right-turn rates, presence of lightings, speed limits, instructive line for left-turn traffic are significant factors affecting crash severities at signalized intersections.

• Korean Journal of Veterinary Research
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• v.44 no.1
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• pp.41-47
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• 2004

The alkaline single-cell gel electrophoresis (SCGE) assay, called the comet assay, has been applied to detect DNA damage induced by a number of chemicals and biological factors in vivo and in vitro. The DNA damage was analysed by tail moment (TM) and tail length (TL), which were markers of DNA strand breaks in SCGE. Human, mouse and rat peripheral blood lymphocytes (PBLs) were irradiated with different doses of $^{60}Co$ ${\gamma}$-rays, e.g. 1, 2, 4, and 8 Gy at a dose rate of 1 Gy/min. A dose-dependent increase in TM (p<0.01) and TL (p<0.01) was obtained at all the radiation doses (1-8 Gy) in human, mouse and rat PBLs. Mouse PBLs were more sensitive than human PBLs which were in turn more sensitive than rat PBLs when the treated dosages were 1 and 2 Gy. However, human PBLs were more sensitive than mouse PBLs which were in turn more sensitive than rat PBLs when the irradiation dosages were 4 and 8 Gy. Data from all three species could be fitted to a linear-quadratic model. These results indicated that there may be inherent differences in the radio-sensitivity among PBLs of mammalian species.

• Journal of Korean Foot and Ankle Society
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• v.13 no.1
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• pp.23-27
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• 2009

Purpose: The purpose of this study was to evaluate the clinical outcome of neglected Achilles tendon rupture treated with reconstruction and augmentation with flexor hallucis longus (FHL) tendon using one incision technique. Materials and Methods: Between July 2006 and March 2008, eleven patients with neglected Achilles tendon rupture received surgical treatment. Through one incision technique, augmentation with auto FHL tendon transfer was performed using a Bio-Interference screw (Arthrex, Naples, FL) and followed by V-Y advancement (5 cases) or gastronemius fascial turn-down flap procedure (6 cases). After mean follow up of 20.7 months (range, 11.8-33.3 weeks), clinical outcomes were evaluated with Visual Analogue Scale (VAS), American Orthopedic Foot and Ankle Society (AOFAS) score, 10 repetitive double heel raise test, 10 repetitive single heel raise test and subjective satisfaction. Results: The length of the gap after debridement was $5.4{\pm}2.0$ cm. The VAS improved from $4.1{\pm}0.9$ to $1.5{\pm}0.8$ at last follow up (p<0.05). The AOFAS score increased from $38.9{\pm}12.2$ to $91.5{\pm}8.9$ at last follow up (p<0.05). Eight patients were satisfied with excellent results and three were satisfied with good results. All patients were able to perform 10 repetitive double heel raise and nine out of eleven patients were able to perform 10 repetitive single heel raise at last follow up. There were no complications including deep infection or re-rupture. Conclusion: Augmentation with FHL tendon transfer and reconstruction with V-Y advancement or turn-down flap through one incision technique appeared to be effective and safe. This technique is recommendable for the treatment of neglected Achilles tendon rupture.

• Korean Journal of Applied Biomechanics
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• v.22 no.1
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• pp.43-53
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• 2012

The purpose of this study was to quantitatively examine the biomechanical variables of Fouette turns for expert and beginner ballet dancers and to determine the difference in the variables between the two groups. sixteen female ballet dancers participated in this study. They were divided into an expert group(age, $25.38{\pm}1.92$ years; height, $168.38{\pm}4.66$ cm; mass, $49.63{\pm}4.41$ kg) and a beginner group(age, $20.88{\pm}1.13$ years; height, $161.63{\pm}7.42$ cm; mass, $48.88{\pm}3.64$ kg) depending on their ballet experience. Descriptive data were expressed as mean ${\pm}$ standard deviation (SD) for all variables including the duration, displacement of the center of the body, velocity of the center of the body, angle of the body segments, angular velocity of the body segments, ground reaction force, lower extremity torque, muscle activity, body weight, age, and body mass. An independence t-test was conducted to determine how the following variables differed between the beginners and experts: duration, displacement of the center of the body, velocity of the center of the body, angle of the body segments, angular velocity of the body segments, ground reaction force, lower extremity torque, and muscle activity. All comparisons were made at the p<0.05 significance level. The results show that the experts scored high on the biomechanical variables, although all the variables were not significant. Significant differences were found in the angle of body segments, angular velocity of the body segments, lower extremity torque, and muscle activity(p<0.05). The findings of this study demonstrate that the experts have the required skill to make an improved Fouette turn. The findings may also help ballet dancers to learn and understand the Fouette turn.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.145-148
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• 2014

Purpose: Serum thyroglobulin (Tg) determination has been reported to be a sensitive indicator of persistent or recurrent differentiated thyroid cancer (DTC) after total thyroidetectomy. In patients free of metastasese and recurrences after a complete thyroidectomy and radioiodine removal for DTC, the Tg is usually <1 ng/mL or can no longer be detected even with TSH stimulation. Therefore, report in low Tg levels and selecting criteria for retest is very important. The purpose of this study was to establish selecting criteria for retest which is efficient at reliability improvement and Turn around time (TAT). Materials and Methods: Sera from 137 patients with DTC were divided into two groups as first(<1.0 ng/mL or >4.0 ng/mL) and second(1.0-4.0 ng/mL). In case of group(<1.0 ng/mL) is in patient free of metastases and recurrences, >4.0 ng/ml is low coefficient of variation (CV%) at internal quality control and good linearity at standard curve. Therefore first group began with Delta/Panic check (D/P) and second group surveyed with the latest results. In that the latest results were <1.0 ng/ml, we checked the thyroxin withdrawal. Finally selected specimen retested with raw specimen. Results: In first group, we was able to reduce the retest rate(30.8% to 7.7%). and In second group, 40% to 5%. The total retest rate was 7.3%. Conclusion: If using the selecting criteria for retest, is helpful to accuracy and quickness of the result report.