• Journal of Pharmaceutical Investigation
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• v.37 no.2
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• pp.107-111
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• 2007

Epigallocatechin gallate (EGCC), a flavonoid, is the main component of green tea extracts. EGCG has been reported to be an inhibitor of P-glycoprotein (P-gp) and cytochrom P450 3A(CYP3A4). This study investigated the effect of long-term administration of EGCG on the pharmacokinetics of verapamil in rats. Pharmacokinetic parameters of verapamil were determined after oral administration of verapamil (9 mg/kg) in rats pretreated with EGCG (7.5 mg/hg) for 3 and 9 days. Compared to oral control group, the presence of EGCG significantly (p<0.01) increased the area under the plasma concentration-time curve (AUC) of verapamil by 102% (coad), 83.2% (3 days) and 52.3% (9 days), and the peak concentration $(C_{max})$ by 134% (coad), 120% (3 days) and 66.1% (9 days). The absolute bioavailability (A.B.%) of verapamil was significantly (p<0.01) higher by 8.4% (coad), 7.7% (3 days), 6.4% (9 days) compared to control (4.2%), and presence of EGCG was no significant change in the terminal half-life $(t_{1/2})$ and the time to reach the peak concentration $(T_{max})$ of verapamil. Our results indicate that EGCG significantly enhanced oral bioavailability of verapamil in rats, implying that presence of EGCG could be effective to inhibit the CYP3A4-mediated metabolism and P-gp efflux of verapamil in the intestine. Drug interactions should be considered in the clinical setting when verapamil is coadministrated with EGCG or EGCG-containing dietary.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.80-80
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• 2016

GPS로 대표되는 위성항법시스템(GNSS : Global Navigation Satellite System)은 지구 주위를 돌면서 연속적으로 항법신호를 보내고 있다. 그 중 지구표면으로부터 반사되는 항법신호를 수신하고 해석함으로써 지구표면에 관한 정보를 취득할 수가 있다. GPS로 대표되는 항법신호는 L밴드를 사용하기 때문에 토양수분의 변화 등에 대한 반사강도의 감도가 비교적 높다고 알려져 있으며, 토양수분 측정 등에 사용할 수 있다. 뿐만 아니라 경량화, 소형화하기 쉬운 점, 능동적 마이크로웨이브 리모트센싱시스템(Active Microwave Remote Sensing System)과 달리 스스로 신호를 발사하지 않기 때문에 관측의 스텔스성(Stealth)dl 뛰어난 점 등의 장점을 가지고 있다. 또한 향후 10년 이내에 준천정위성(QZSS), Galileo, COMPAS, IRNSS 등 많은 위성항법시스템이 본격 운용되어 GPS와 함께 120기 정도의 항법위성이 항법신호를 송신할 예정이므로 이용 가능성은 크게 늘어날 것으로 기대된다.한편, 항법위성을 이용한 바이스테이틱 리모트센싱은 반사파의 강도가 상당히 미약하기 때문에 정량적 계측모델의 구축은 미미한 상태이다. 즉, 지상 타워에서의 관측, 항공기에서의 관측, 소형 위성에서의 관측 등이 수행되고 있으나, 타워관측과 같이 지상의 거의 동일한 장소를 계속적으로 관측하는 경우를 제외한 기존의 연구에서는 토지의 피복상황이나 토양수분 등의 상관관계를 제시하는 수준으로써 정량적인 계측방법은 아직 확립되어 있지 않다. 이러한 관점에서 본 연구에서는 GPS위성으로부터의 항법신호를 이용하여 지구표면에 관한 정보를 얻는 바이스테이틱 리모트센싱(Bi-static Remote Sensing) 기술을 바탕으로 육지면과 해면의 판별에 신호특성이 어떻게 유효한가를 실험적으로 밝혔다. 이러한 기술은 토양수분 측정 등 수자 원인자를 추출하는데 유용할 뿐만 아니라 수면의 고도 측정, 해상풍 산출 등에도 응용 가능하다.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.215-215
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• 2017

The preference for domestic cereal crop of Setaria Italica has been increased with the recent interest in healthy foods. However, the productivity of Korean domestic produce, which has been decreasing due to the lack of cultivation technology and the low rate of mechanization during cultivation. Increase of germination ability will have a positive effect on the cultivation by reducing the labor of the manpower consuming and weeding work. Therefore, red light, ultrasonication, liquid priming and liquid smoke treatment that are effective for the germination of the seeds evaluated. The seeds of 1.4mm or more were used for the experiment. The priming solution used in the experiment was 1% $KH_2PO_4$ (74mM). During the priming, the light treated seeds at 2000 lux for 15, 30, 60 and 120 minutes. Ultrasonicationd treatment was performed for 5, 10, and 20 minutes at exposures of 60%, 80%, and 100% of ultrasound up to 21.6 kHz during priming. Light or ultrasound treated seeds transferred to priming treatment at $15^{\circ}C$ for 24 hours. The treatment of the liquid smoke was divided into the treatment of the liquid smoke alone and the treatment of the liquid smoke with the priming. The liquid smoke alone was diluted with distilled water without priming solution and the treatment of the liquid smoke was diluted with the salt priming solution. Both treatments were performed at 0.0%, 0.5%, 1.0%, 5.0%, and 10.0% of the liquid smoke (pH7) concentration at $15^{\circ}C$ for 6 hours. After each treatment, the seeds were dried to moisture content ranged 5-8% at $25^{\circ}C$ for 24 hours. All treatments showed better results than the non-treated control. Light treatment for 120 minutes improved for germination percentage (GP), Germination uniformity (GU) and heath seed percentage (HS). Ultrasonication treatment was most effective when treated with ultrasound at 21.6 kHz for 5 minutes in all germination characteristics. Ten % of the liquid smoke increase in 92% GP, 1.8 days MGT, $54%{\cdot}day^{-1}GR$, 0.76 GU and 88% HS comparing to non-treated control (72% GP, 2.3 days MGT, $45%{\cdot}day^{-1}GR$, 1.48 GU, and 63 % HS). This study showed that it is possible to obtain high germination by adding liquid smoke treatment to the seeds supplied to the farmers. The efficacy of light, ultrasonication, inorganic salt priming, and liquid smoke treatment on the seeds found in the experiment will be a positive alternative to labor force problems in the cultivation by improving germination.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.8C
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• pp.1104-1112
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• 2004

In this paper, we establish measurement methods of vibration frequency for three-dimensional behavior measurement of large-scale structure using laser and high-speed CCD camera. We project the diode laser having a smaller fluctuation on the object plane attached to the structure and measure the displacement of the structure using a precise relative measurement algorithm. When we use high-speed(120 frames/sec) CCD camera, we can measure the vibration frequency having the uncertainty within 0.5% by taking FFT on the displacement, from 0Hz to 40Hz. And we also confirm the reliability and economical string of the suggested measurement method of vibration frequency of the structure by showing the accuracy of displacement measurement using laser is comparable to that of relative positioning methods using GPS.

• Proceedings of the Korean Society of Computer Information Conference
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• 2009.01a
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• pp.117-120
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• 2009

본 연구는 디자인패턴 설계유형에 따라 Mobile 장치를 이용하여 현장의 농작물 중 벼의 생육 정보 및 생산 정보와 GPS를 이용하여 농작물의 위치정보를 서버에 있는 DB에 사용자의 권한별로 삽입/삭제/수정/검색을 할 수 있고, GIS를 이용하여 사용자의 위치 및 벼의 위치 정보를 수치지도 상에 보여 주는 시스템을 구축한다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.5
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• pp.109-120
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• 2017

It is important to estimate objectively in the driving test. Especially, the driving test is examined by totally driving ability, rule observation and situational judgement. For this, a grading automation system for driving test was presented by using GPS, sensor data and equipment operation informations. This system is composed of vehicle mounted module, automatic grading terminal, data controller, data storage and processing server. The vehicle mounted module gathters sensor data in the car. The terminal performs automatic grading using the received sensor data according the driving test criterion. To overcome the misposition of vehicle in the map due to GPS error, we proposed the automatic grading system by map matching method, path deviation and return algorithm. In the experimental results, it was possible to grade automatically, display the right position of the car, and return to the right path under 10 seconds when the vehicle was out of the shadow region of the GPS. This system can be also applied to the driving education.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9249-9258
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• 2014

Background: The encapsulation of curcumin (Cur) in polylactic-co-glycolic acid (PLGA) nanoparticles (Cur-NPs) was designed to improve its solubility and stability. Conjugation of the Cur-NPs with anti-P-glycoprotein (P-gp) antibody (Cur-NPs-APgp) may increase their targeting to P-gp, which is highly expressed in multidrugresistance (MDR) cancer cells. This study determined whether Cur-NPs-APgp could overcome MDR in a human cervical cancer model (KB-V1 cells) in vitro and in vivo. Materials and Methods: First, we determined the MDR-reversing property of Cur in P-gp-overexpressing KB-V1 cells in vitro and in vivo. Cur-NPs and Cur-NPs-APgp, in the range 150-180 nm, were constructed and subjected to an in vivo pharmacokinetic study compared with Cur. The in vitro and in vivo MDR-reversing properties of Cur-NPs and Cur-NPs-APgp were then investigated. Moreover, the stability of the NPs was determined in various solutions. Results: The combined treatment of paclitaxel (PTX) with Cur dramatically decreased cell viability and tumor growth compared to PTX treatment alone. After intravenous injection, Cur-NPs-APgp and Cur-NPs could be detected in the serum up to 60 and 120 min later, respectively, whereas Cur was not detected after 30 min. Pretreatment with Cur-NPs-APgp, but not with NPs or Cur-NPs, could enhance PTX sensitivity both in vitro and in vivo. The constructed NPs remained a consistent size, proving their stability in various solutions. Conclusions: Our functional Cur-NPs-APgp may be a suitable candidate for application in a drug delivery system for overcoming drug resistance. The further development of Cur-NPs-APgp may be beneficial to cancer patients by leading to its use as either as a MDR modulator or as an anticancer drug.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.217-217
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• 2017

Seed priming leading to improved emergences, germination speed and uniformity under unfavorable conditions without loss of longevity are the best level of techniques. We studied the possibility to obtain primed seed with reduced mean germination time (MGT) and uniformity but with simple, fast and effective methods. The experiments were carried out at $15^{\circ}C$ for 16 hours with priming treatment. To compare the effects of each treatment, we used 200mM $CaCl_2$ priming or hydro priming or no imbibition after ultrasonication or red light treatment. The light treatment was performed by irradiating 2000 lux of red light for 15, 30, 60, and 120 minutes. Addition, in order to investigate the effect of the priming solution, treated at 200mM $CaCl_2$ for 8 hours. Ultrasonication treatment was performed for 5, 10, and 20 minutes at exposures of 13.0, 17.3, and 21.6 kHz during priming. For liquid smoke (LS) treatment, seed soaked in 0%, 0.5%, 1.0%, 5.0% and 10.0% of diluted water and 200mM $CaCl_2$ solution. After each treatment, the seeds were dried to moisture content ranged 5-8% at $25^{\circ}C$ for 24 hours. The effect of seed treatment was evaluated with germination percentage (GP), MGT, germination index(GI), germination rate(GR), Germination Uniformity(GU) and heath seed percentage(HS). For several factors tested, we found that the desired germination improvement could be obtained by treating the seed with ultrasonication at 17.3 kHz for 5 minutes in water or red light exposure at 2000 lux for 120 min in water that resulted very similar to those used to 200mM $CaCl_2$ priming for 16 hrs. However, LS treatment showed no improvement in all diluted solution. Therefore, the methods applied ultrasonication and red light treatment showed high potential for fast and easy treatment avoiding pollution of salt solution waste.

• Journal of the Korea Society of Computer and Information
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• v.12 no.1 s.45
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• pp.189-197
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• 2007

Developed safety system which transfers danger information to rear cars for accident prevention when drivers detect a accident, a dropping or a freezing during driving on the high way. To prevent an accident, each vehicles mount OBU which is made up of a GPS unit and a transmitter-receiver and the trace of road is always renewed and saved in OBU per a regular past distance. When the driver see dangerous situation, transfer a danger pattern and a trace information by pressing button. All cars which receive information compare the received data with the original data. And then, only cars which are located at the rear in a regular distance respond and occur a warning. Performed a road test at the rate of $30{\sim}50$ kilometer a hour using two test cars which saved about 120meter's space between them were mounted OBU which had 447Mhz transceiver. As a result of the experiment, communication between test cars had no problem. Accordingly, it can use a safety driving device because driver can notice a danger situation and set themselves ready for it using this system in advance.

• Journal of environmental and Sanitary engineering
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• v.21 no.1 s.59
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• pp.21-34
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• 2006

To investigate anti-HIV-1 activity of water soluble chitosans, sulfated chitosan derivatives were prepared in mild condition. Various sulfated chitosan derivatives (N-3,6-O-S-chitosan, N-desulfated 3,6-O-S-chitosan, 3,6-O-S-chitin, and 3,6-O-sulfated-N-(o-carboxybenzoyl) chitosan) were synthesized with sulfurtrioxidepyridene complex in pyridine solvent. Characterization of the sulfated chitosan derivatives was carried out by $^{13}C$ NMR and IR spectroscopies. To observe ionic reaction properties, pKas of the sulfated chitosan derivatives and chitosan of low molecular weight were estimated by potentiometric titration. The sulfated chitosan derivatives had high water solubility, pKas (pKa : 7.7) of N-3,6-O-S-chitosan and N-desulfated 3,6-O-S-chitosan were increased than pKa of water insoluble chitosan (pKa : 6.2), These results suggest the participation of electrostatic interaction of amino and sulfate groups on the sulfated chitosans. Anti-HIV-1 drugs, such as AZT, ddC, and ddI for anti-HIV activity had higher selective index compared with SCB-chitosan but N-3,6-O-S-chitosan has shown higher selective index compared with ddC and ddI as HIV drugs.. These results suggest that sulfated chitosan derivatives were expected as an anti-HIV drug with differential driving force mechanism against some nucleoside analogs drug in the future.