• KOREAN JOURNAL OF CROP SCIENCE
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• v.50 no.6
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• pp.369-377
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• 2005

Precise application of topdressing nitrogen (N) fertilizer is indispensible for securing high yield and good quality of rice and minimizing N losses to the environment as well. For precise N management, growth and nitrogen nutrition status (NNS) should be diagnosed rapidly and accurately. The objective of the study was to evaluate the applicability of vegetation index (VI) calculated from hyperspectral canopy reflectance measurement and SPAD reading to nondestructive in situ diagnosis of growth and NNS of rice. Canopy reflectance, SPAD read­ing, growth parameters, and NNS characteristics were measured from various N treatments to evaluate the relationships among them for two cropping seasons from 2001 to 2002. The correlation coefficient of VIs with variables of growth and NNS increased positively as rice canopy became more closed. Regardless of growth stages, VIs had significantly high correlations with LAI, shoot dry weight (DW), shoot N content and nitrogen nutrition index (NNI). Those correlation coefficients increased steadily before heading stage as rice grew up. However, tiller number and leaf N concentration showed significantly high correlations with VIs only at and after panicle initiation stage (PIS). Among the VIs, RVIgreen had significantly higher correlation with the measured parameters than the other VIs: it showed correlation coefficients greater than 0.8 with leaf and shoot N concentration and DW, and much higher coefficients greater than 0.9 with LAI, shoot N content, and NNI. At LAI of below 2.5, VIs had non-significant or low correlations with the growth and NNS indicators due to the background effects. SPAD reading had significantly high correlation with leaf N concentration and NNI at each growth stage. In addition, it had significant correlations with variables of growth and NNS at PIS and booting stage, particularly, at booting stage. Though SPAD reading had a significantly high correlation value at a given growth stage in each year, it showed very weak relationship with variables of growth and NNS when pooled across growth stages and years. In conclusion, RVIgreen was found to be the most reliable VI to estimate the growth and NNS of rice around at PIS, but SPAD reading had much limitations.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.38C no.12
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• pp.1095-1105
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• 2013

This paper proposes the RDMS(Rough Set Theory based Disease Monitoring System) which efficiently manages diseases in Healthcare System. The RDMS is made up of DCM(Data Collection Module), RDRGM(RST based Disease Rules Generation Module), and HMM(Healthcare Monitoring Module). The DCM collects bio-metric informations from bio sensor of patient and stores it in RDMS DB according to the processing procedure of data. The RDRGM generates disease rules using the core of RST and the support of attributes. The HMM predicts a patient's disease by analyzing not only the risk quotient but also that of complications on the patient's disease by using the collected patient's information by DCM and transfers a visualized patient's information to a patient, a family doctor, etc according to a patient's risk quotient. Also the HMM predicts the patient's disease by comparing and analyzing a patient's medical information, a current patient's health condition, and a patient's family history according to the rules generated by RDRGM and can provide the Patient-Customized Medical Service and the medical information with the prediction result rapidly and reliably.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.310-317
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• 2009

Dens evaginatus is a dental anomaly involving an extra cusp or tubercle that protrudes from the occlusal surface of the affected tooth. The prevalence of dens evaginatus is 1 to 4 percent, and dens evaginatus is observed most commonly in premolars. It can be worn or fractured easily, resulting in pulpal exposure, pulpal infection, loss of vitality, facial infection and osteomyelitis. Since the tooth frequently has the immature apex when the tubercle is fractured, there is difficulty in treatment. Although calcium hydroxide is widely used for pulp treatment of an immature permanent tooth, several alternatives have been suggested to reduce patient's appointments. Mineral trioxide aggregate is considered biocom-patible and has excellent marginal sealing ability. In addition, it can minimize patient's visits. In this case report, apexification with MTA was attempted on the immature premolars in patients with cellulitis patient, caused by pulp necrosis due to dens evaginatus. Favorable clinical and radiologic results were achieved. In one case, continued root formation was observed.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.813-816
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• 2005

최근 휴대폰의 활용 범위는 단순히 사용자간의 통신이라는 기본적인 목적을 넘어서 다양한 기능을 제공하고 있다. 그중 휴대폰에 카메라를 탑재하여 디지털 카메라의 기능을 혼합한 휴대폰은 최근 각광을 받고 있으며 휴대폰에 탑재된 카메라의 기능은 디지털 카메라의 메가 픽셀 급 화질을 제공하는 정도의 수준으로 발전하였으며 이미 그 수요는 대중화되어 가고 있다. 이런 카메라 폰을 응용한 연구 분야로 생체 인식 기술을 적용할 수 있으며, 본 논문에서는 휴대폰 환경에서의 홍채 인식을 위한 홍채 영역에서의 홍채 코드 추출에 관한 방법을 제안한다. 휴대폰에서의 홍채 인식에 사용되는 홍채 코드 추출 과정은 다음과 같다. 먼저 휴대폰 카메라를 통해 얻은 메가 픽셀 급 영상($2048{\times}1536$ pixel 8bit gray Image)에서 동공위치 추적 & 홍채 영역 추출 알고리즘[1]을 이용하여 눈 영상($640{\times}480$ pixel 8bit gray Image))을 추출한다. 이렇게 추출된 눈 영상 중에 홍채 코드 인식 에러율을 좀더 낮추기 위해 눈썹영역, 안경에 의해 반사되는 반사광(Specular Reflection), 눈꺼풀 영역을 눈 영역에서 제거 하는 과정을 거친다. 이 논문에서는 위와 같은 과정을 거쳐 얻어진 홍채 영상에 그대로 극좌표 가버 필터[2]를 씌워 홍채 코드를 추출해내기 때문에 기존 보간법을 이용한 스트레칭 된 홍채 영상에서의 홍채 코드 추출보다 잘못된 홍채 코드 정보를 줄일 수 있으며 휴대폰이라는 특수한 환경에서의 홍채 코드 추출이란 점을 고려하여 가버 필터를 고주파와 저주파로 나누어 미리 설계해두어 좀더 빠르고 정확한 홍채 코드를 추출해 내는 방법을 제안한다. 실험 결과, 기존 방식보다 극좌표 가버 필터를 사용한 홍채 코드 추출 실험에서 보다 높은 인식률을 보였다.

• Korean Journal of Weed Science
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• v.18 no.3
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• pp.214-224
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• 1998

This study was conducted to develop labor and chemical cultural practice improvement for weed control in ginseng field. Five crop species were screened in vitro and three crop extracts were sprayed in the test allelopathic effect for weed species. Methyl alcohol extracts of rice, oat, rye and wheat straw showed inhibitory effect on the germination of six weed species, Amaranthus retroflexus, Chenopodium album, Arthraxon hispidus, Digitaria adscendens, Echinochloa crus-galli, and Setaria viridis. Especially, extract of oat straw was most effective to inhibit the germination of six weed species tested. Also, spraying the extract solution of rice, rye and wheat straw was effective to inhibit the growth of weeds in ginseng field. Ginseng root length, diameter, fresh and dry weight in extract spraying plot were higher than those of non-treatment plot.

• Analytical Science and Technology
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• v.13 no.5
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• pp.666-674
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• 2000

The present study describes an analytical method for the determination of polybrominated biphenyls (PBBs) in biota samples by gas chromatography-mass spectrometry (GC/MS). PBBs are extracted twice from 20 g samples with mixture solvent 40mL acetone and 80mL hexane using ultrasonic agitation for 20 min. Lipids in extracts are degraded by concentrated sulfuric acid and then PBBs are purified with Florisil column. The purified extracts are analyzed by GC/MS-selected ion monitoring mode for the quantitation of PBBs in biota sample. The overall recovery yields of PBBs range between 77 and 111% under these experimental conditions.

• Food Science and Preservation
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• v.7 no.4
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• pp.373-379
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• 2000

The Ulmi corex extract was prepared using various solvents to investigate the availability as a natural antioxidant. The extracts were added to lard emulsion and the antioxidant activities were compared. The extract that had a greater antioxidant activity was fractionized. Then the antioxidant activity and substrate specificity of the fraction were examined and optimum concentration of addition was determined. To observe the antioxidative effect of the fraction in vivo, an inhibition rate of lipid peroxidation from which might be derived was measured using a microsome in rat's liver. Among the extracts of Ulmi cortex, the extract from water had the best antioxidant activity, and the addition of 0.05% (w/w) of ethyl acetate fraction showed similar antioxidant activity to a synthetic antioxidant, butylated hydroxyanisole(BHA). Ethyl acetate fraction (0.05%, w/w) also presented the antioxidative effect in lard, soybean oil, palm oil, and com oil. The inhibition of lipid peroxidation in liver microsome showed feater in the ethyl acetate fraction than caffeic acid in both nonenzymatic peroxidation (Fe$\^$++/ascorbate system) and enzymatic peroxidation (Fe$\^$++/-ADP/NaDPH system).

• Polymer(Korea)
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• v.32 no.5
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• pp.415-420
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• 2008

The porcine small intestinal submucosa (SIS) without immunorejection responses and hyalunonic acid (HA) can be used as biomaterials. In this study, we tried to design and characterize novel sponge. SIS- HA sponge was prepared by freeze-drying after addition 1wt% HA solution into fabricated SIS sponge. Sponge was crosslinked with 1-ethyl-(3-3-dimethyl aminopropyl) carbodiimide hydrochloride (EDC) solution with 100mM concentration for 24 hrs and lyophilized. SIS-HA sponge was characterized by scanning electron microscopy and fourier transform infrared spectrometer. And water absorption ability of sponge was evaluated. We seeded NIH/3T3 cells in SIS-HA sponge and cellular attachment was assayed by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltertazolium-bromide (MTT) test. We demonstrated presence of HA in SIS-HA sponge from C-O functional group observed by the FT-IR analysis. Moreover, we confirmed low cytotoxicity and high cell viability of the SIS-HA sponges. Therefore, we could expect that SIS- HA scaffolds are applicable for the tissue regeneration.

• Applied Chemistry for Engineering
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• v.32 no.5
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• pp.556-561
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• 2021

Recently, iron oxide nanoparticles have been used as the subject of many studies on drug delivery system (DDS) due to their excellent magnetic properties and biocompatibility in response to external magnetic fields. In this study, hyaluronic acid-superparamagnetic microneedles (HA-SMNs) and carboxy methyl cellulose-superparamagnetic microneedles (CMC-SMNs) containing superparamagnetic iron oxide nanoparticles (SIONs) were prepared with HA and CMC as a matrix materials of MNs (microneedles). Various properties of SMNs were then investigated with scanning electron microscopy (SEM), superconducting quantum interference device-vibrating sample magnetometer (SQUD-VSM), frequency mixing magnetic detection (FMMD), and polymer/bio membrane. The SQUID-VSM measurements showed superparamagnetism of HA-SMNs and CMC-SMNs containing SIONs. The FMMD results demonstrated that the signal intensity changed significantly as the concentration of SIONs increased. In addition, SMNs exhibited the average skin permeability intensities on the bio membrane for HA-SMNs and CMC-SMNs were 92.5 and 98.5%, respectively. These results suggested that SMNs could be utilized as deliver materials for a TDDS and MR molecular imaging.

• Korean Chemical Engineering Research
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• v.57 no.2
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• pp.232-238
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• 2019

Polyethylenimine-crosslinked chitin (PEI-chitin) was developed as a biosorbent to effectively remove dyestuffs from dye-containing wastewater. A representative reactive dye, Reactive Orange 16 (RO16) was used as a model dye. The effect of pH, isotherm, kinetic and desorption experiments were performed to evaluate the adsorption/desorption ability of PEI-chitin for RO16. As a result, the maximum adsorption capacity calculated by the Langmuir model was 266.3 mg/g at pH 2, and the time needed for adsorption equilibrium was evaluated to be about 20, 60, and 240 min for 50, 100, and 200 mg/L, respectively. The desorption experiments were carried out using various eluents such as ammonia/ethanol mixture, NaOH, $NaHCO_3$, and $Na_2CO_3$, and the highest desorption rate was 75.24% in the ammonia/ethanol mixture.