• Natural Product Sciences
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• v.8 no.2
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• pp.44-47
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• 2002

The effects of Eurycoma longifolia Jack on masculine copulatory behaviour were studied in the middle aged male Sprague-Dawley rats, 9 months old and retired breeders after dosing them with 500 mg/kg twice daily for 10 days prior to test. The test lasted for 30 minutes after a 20 minute adaptation period, was carried out on the 11th day during the dark phase of the light-dark cycle (2000-0700 hours) and in subdued light, using a modified copulation cage but with the presence of a piece of mirror of appropriate size to facilitate observation. Results showed that the mean values of EL-1, EL-2 and EL-3 of the control middle aged male rats were 103.20 sec, 91.21 sec and 80.00 sec but were significantly (p<0.05) increased to 118.40-120.20 sec, 101.24-171.28 sec and 100.42-110.21 sec respectively in the methanol-chloroform, methanol-butanol-water and methanol-butanol treated middle aged male rats. However, further results also showed that PEI-1 and PEI-2 of the control middle aged male rats were 182.30 sec and 257.2 sec but were significantly (p<0.05) decreased to 100.42-121.31 sec and 40.21-132.31 sec respectively in the methanol-chloroform-butanol-water and methanol-butanol treated middle aged male rats. In conclusion, this study showed that although E. longifolia Jack continued to enhance the sexual activity of the middle aged male rats by extending the duration of coitus and decreasing the refractory period between the different series of copulation, but to a smaller degree as compared to sexually active, adult male rats (Ang and Sim, 1997).

• Journal of Radiation Protection and Research
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• v.33 no.1
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• pp.41-46
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• 2008

To estimate the finger dose absorbed by $^{99m}Tc$ injection, simulations are carried out to calculate the dose equivalent of each finger per second with radioactivity of 370 MBq, based on the GEANT4 simulator. For the $^{99m}Tc$ source of the volume of 0.4mL and the radioactivity of 370 MBq, we obtained the dose equivalent of the right thumb ($0.29\;{\mu}Sv{\cdot}sec^{-1}$), the right index finger ($1.19\;{\mu}Sv{\cdot}sec^{-1}$), the right middle finger ($1.07\;{\mu}Sv{\cdot}sec^{-1}$), the left thumb ($4.36\;{\mu}Sv{\cdot}sec^{-1}$), and the left index finger ($3.37\;{\mu}Sv{\cdot}sec^{-1}$), respectively. This simulation results may serve as a useful data in the prediction of finger dose absorbed by $^{99m}Tc$ injection.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.8-14
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• 1985

A circulation water channel with observational section of $4m{\times}2.4m{\times}1m(length{\times}breadth{\times}depth)$ and the maximum channel flow speed of 2 m/sec was designed for model tests of fishing gears. It consists of 6 sections evenly divided for easy connection. Two observational acryl windows of $1.2m{\times}1.5m$ and 2cm thick are provided. Steel deflection plates, equally spaced in 20-40cm, are fixed at corners of the channel to reduce the loss of water pressure head through the channel. The flow in the channel is controlled by D.C. motor control system with 50 H.P. driving propeller system. A series of model testing capabilities for fishing gear have been examined and the results are as follows. 1) The speed of water flow was in the range from zero to 2.3 m/sec. 2) The difference between the velocity of channel flow along the center line and that along both sides in the channel was less than 0.2 m/sec.

• Journal of the Korean Chemical Society
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• v.13 no.3
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• pp.221-228
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• 1969

The nucleophilic addition rate constants of n-amyl-, n-hexyl-, n-octyl-and n-decyl mercaptide ion to 3,4-methylenedioxy-${\beta}$-nitrostyrene were determined and found to be 2.82 ${\times}10^8$ $M^{-2} .sec^{-1}$, 1.00 ${\times}10^8$ $M^{-2}.sec^{-1}$, 2.23 ${\times}10^8$ $M^{-2} .sec^{-1}$ and 1.77 ${\times}10^8$ $M^{-2}.sec^{-1}$ respectively. At low pH, for n-amyl-, n-hexyl-, n-octyl-and n-decyl mercaptan the values determined are 2.82 ${\times}10^{-2}$ $M^{-1} . sec^{-1}$, 1.95 ${\times}10^{-2}$ $M^{-1} . sec^{-1}$, 7.08 ${\times}10^{-2}$ $M^{-1} . sec^{-1}$ and 5.63 ${\times}10^{-2}$ $M^{-1} . sec^{-1}$ respectively. The rate equations which can fully explain the addition mechanism over wide pH range were also be obtained.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.4
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• pp.721-728
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• 2018

This paper introduces various linear block error correction code and compares performances of the correction circuits. As the risk of errors due to power noise has increased, ECC(: Error Correction Code) has been introduced to prevent the bit error. There are two representatives of ECC structures which are SEC-DED(: Single Error Correction Double Error Detection) and SEC-DED-DAEC(: Double Adjacent Error Correction). According to simulation results, the SEC-DED circuit has advantages of small area and short delay time compared to SEC-DED-DAEC circuits. In case of SED-DED-DAEC, there is no big difference between Dutta's and Pedro's from performance point of view. Therefore, Pedro's code is more efficient than Dutta' code since the correction rate of Pedro's code is higher than that of Dutta's code.

• The Journal of Korean Physical Therapy
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• v.12 no.3
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• pp.349-359
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• 2000

The aim of study was to evaluated the possible role of cranial artery velocity in headache pathogenesis. The present study was studied of five headache(F=5. Mean $age=29.80\pm6.76yrs$) were compared to 4 controls(F=4, Mean $age=29.00\pm5.48yrs$). Transcranial doppler ultrasonography(TCD) is a new non-invasive and easily applicable method to evaluate flow velocities of the intracranial and extracranial cerebral arteries. TCD was performed with standard method to measure the mean Flow Velocity(MFV) of the middle and posterior cerebral arteries, the internal carotid artery, the vertebral and the basilar artery. We reviewed the whole TCD results performed at Taejon Veterans Hospital from October. 11. 2000 to November. 10. 2000. Mean flow velocities in headaches and controls at their 6 decades are $28.00\pm3.61cm/sec$ and $41.25pm1.71cm/sec$ in lent PCA (P<0.01), $50,000\pm23.07cm/sec$ and $82.75\pm15.59cm/sec$ in right MCA(P<0.05), $26.20\pm4.82cm/sec$ and $45.50\pm4.51cm/sec$ in fight PCA(P<0.01). $26.60\pm4.56cm/sec$ and $38.25\pm4.92cm/sec$ in right VAC(P<0.01). After treatment for 2 weeks, mean of velocity on pre treatment and post treatment and post treatment are $28.00\pm3.61cm/sec$ and $38.20\pm5.81cm/sec$ in left PCA (P<0.05), $26.20\pm4.827cm/sec$ and $39.20\pm5.54cm/sec$ in right PCA(P<0.05), $40.60\pm9.18cm/sec$ in right VA(P<0.01). It is concluded that Electrical Therapy for two weeks was effected to promote Mean Flow of Velocity in cranial artery. Mean of velocity in cranial artery with headaches observed in this study was lower than controls, but MFV was promote after treatment for 2 weeks.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.271-276
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• 2008

Ribosome stalling by nascent sticky peptide has been reported in several organisms across the kingdom. To test whether small subunit (SSU) rRNA is involved in this phenomenon, we developed a genetic system that utilized the specialized ribosome system to isolate SSU rRNA mutants that enable ribosomes to bypass the SecM-derived sticky peptide in protein synthesis. In this system, CAT-SecM mRNA, which encodes CAT protein containing the sticky peptide derived from SecM, is only translated by specialized ribosomes. These ribosomes were shown to transiently stall on CAT-SecM mRNA followed by the synthesis of the sticky peptide. Expression of specialized ribosomes resulted in the decreased steady-state level of CAT-SecM mRNA, which is consistent with a notion that ribosome stalling induces mRNA degradation. Isolation and characterization of SSU rRNA mutations using this genetic system that are sufficient to circumvent ribosome stalling induced by the SecM-derived sticky peptide will provide evidence of SSU rRNA function in mRNA cleavage.

• Journal of Korean Society of Transportation
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• v.8 no.2
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• pp.43-54
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• 1990

Six Levels of Service are defined for each type of facility for which analysis procedures as available. They are given letter designations, from A to F with Level of Service A representing the best operating conditions and Level of Service F the worst. Yet the appropriate criteria by vehicle delay model in our situations are not formed. Therefore, The objective of this study is to form the criterion of by average approach delay based on the criterion of V/C ratio. Level-of-Service criterion of this study by TRANSYT-7F Delay Model is as follows. A:${\leq}35.5$ sec, B:${\leq}41$ sec, C:${\leq}48$ sec, D:${\leq}56.5$ sec, E:${\leq}66.5$ sec, F:>66.5 sec.

• 한국해양학회지
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• v.1 no.1_2
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• pp.7-13
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• 1966

한국해협(韓國海峽)을 통과(通過)하는 해수용적수송량(海水容積輸送量)의 계절(季節) 및 영년변화(永年變化)에 대(對)하여 기존자료(旣存資料)를 써서 지형유리론(地衡流理論)에 입각(立脚)하여 계산(計算) 음미(吟味)하였다. 한국해협(韓國海峽)을 통과(通過)하는 “쯔시마” 난류(暖流)의 북방수송량(北方輸送量)은 약 $2{\times}10^6m^3$/sec의 우세(優勢)한 년변화량(年變化量)을 갖고 동춘절(東春節)의 $0.33{\times}10^6m^3$/sec 로부터 하추절(夏秋節)의 $2.21{\times}10^6m^3$/sec 사이에서 변화(變化)한다. 그리고 정미(正味)의 수송량(輸送量)의 년평균치(年平均値)는 1935년(年)의 $1.3{\times}10^6m^3$/sec 로부터 1939년(年)의 $0.8{\times}10^6m^3$/sec사이로 변화(變化)하며 영년변화량(永年變化量)은 약 $0.5{\times}10^6m^3$/sec로서 년변화량(年變化量)의 약 1/4밖에 안된다. 북방수송량(北方輸送量)의 영년변화(永年變化)는 약(約) 4년주기(年週期)를 갖는 것 같이 보인다.

• Journal of the Korean Vacuum Society
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• v.5 no.4
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• pp.284-291
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• 1996

We have implemented a fast pressure control system for the transport chamber of a high vacuum cluster tool for advance semiconductor fabrication and evaluated its performance. To overcome the typically slow response of mass flow controllers, the modified experimental method is used very effectively to optimize the pressure control procedure. We successfully obtained quite fast pressure control by adjusting the starting time and eht tuning constants by the Ziegler-Nichols method. In the transport pressure $10\times 10^{-5}$ torr, actual pressure control starts from 4 sec after an initial gas load of 2.1 sccm. As a result, optimum conditions for the tuning constants are the rise rate of 0.02 torr/sec, the lag time of 0.15 sec, and the sampling period of 0.5 sec. Then the settling time is about 9 sec within about $\pm$0.5% for the referenced value. This settling time is enhanced above 75 percents in comparison with conventional experimental method. To account for the experimental effects observed, a theoretical model was developed. This experimental result has a tendency to fit with the theoretical result of $\omega$=-1.0.