• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.2
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• pp.205-220
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• 2010

Purpose : To analyze the effect of implant designs on insertion torque and stress by performing a comparative study on von Mises stress, torque and normal force through a three-dimensional finite element analysis. Materials and methods : Models of the screw type implant were used to model the implant as a form placed in the mandibular premolar region applying a three-dimensional finite element method. Screw type implant designs were classified into 4 types of parallel ones and 7 types of tapered ones. Other factors were simulated to represent clinical environment. Results : In parallel implant designs, higher and wider threads resulted in higher insertion torques and higher stress distributions. In tapered implant designs, changes in the taper led to remarkable differences in the insertion torques. It was difficult to determine a certain tendency of stress distribution around the implants since the stress level was too high around them. In tapered implant designs, smaller implants demonstrated lower insertion torques than the original type and were relatively less dependent on the degree of taper. Tapered implants showed higher insertion torques and higher stress distributions than parallel implants. Conclusion : According to this study, although the tapered implant demonstrated a higher insertion torque than the parallel implant, stress tended to be concentrated in the entire fixture of the tapered implant due to the inefficient stress distribution.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.402-408
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• 2007

This study was conducted in order to evaluate the antioxidant activity of extruded ginseng in different extracted fractions. Each of the fractions obtained from extruded ginseng and ginseng (control) were extracted with 80% ethanol, and then the lipophilic components were removed with ether while the hydrophilic components were separated with water-saturated butanol. Each of the 80% ethanol/butanol/water layers were collected and evaporated to acquire samples for tests of saponin content and antioxidant activity. The antioxidant activity of extruded ginseng fractions and ginseng fractions were determined via the oxygen radical absorbance capacity (ORAC) assay. Overall, the extruded ginseng samples harbored saponin contents of 2.2 (Rg1), 2.3 (Re), 1.2 (Rc), 1.3 (Rb2), and 2.2 (Rd) times that measured in the ginseng prior to extrusion. Antioxidant capacity was also higher, not only in the 80% ethanol/butanol which harbor a significant quantity of saponin, but also in the water fractions, which harbor relatively low quantities of saponin as compared to the control samples. All three of the fractions extracted from extruded ginseng evidence significantly higher antioxidant capacity than the controls (0.05

• Journal of the Korean Society of Radiology
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• v.10 no.3
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• pp.215-222
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• 2016

X-ray mammography is the most effective method for the diagnosis of calcified lesions of various breast diseases. To reduce patient dose and to obtain optimal image required for diagnosis, the performance of the mammography system should be maintained continuously. Because the target (anode) angle of the X-ray tube is measured from the central X-ray, the effective angle can be slightly different in view of the position on the detector, which can result in degrading spatial resolution of the imaging within the field of view. In this study, we measured the MTF to examine spatial resolution for positions on the detector in the digital mammography system. For a tungsten wire of $50{\mu}m$ diameter, the highest spatial frequency was obtained. It meant that a wire diameter for measuring MTF through LSF should be small compared to the pixel size of the detector used in the mammography system. The spatial resolution showed slightly different performance according to positions on the detector. The center position gave the best spatial resolution and positions away from the center showed the degraded performance although the difference of the spatial resolution was small. The effective focal spot size of the full width at half maximum also showed similar result. It concluded that the slightly increase of the effective focal spot size gave the degradation of the spatial resolution for positions on the detector.

• Applied Biological Chemistry
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• v.51 no.3
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• pp.188-193
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• 2008

This study was conducted to investigate the effect of moisture content and pressure on extraction yield, crude saponins and ginsenoside contents of puffed Korean ginseng. Puffed ginsengs showed relatively higher extraction yield ($50.0{\sim}62.1%$) and amounts of crude saponins ($19.6{\sim}48.8$ mg/g ginseng) than no-puffed ginseng ($37.6{\pm}0.8%$ and $11.0{\pm}1.0$ mg/g ginseng), respectively. The highest extraction yield and amounts of crude saponins were obtained in 8.0% moisture content sample puffed at 10 $kg_f/cm^2$. In HPLC analysis, amounts of measured major ginsenosides (Rb1, Rb2, Rc, Rd, Re, and Rg1) decreased with increasing puffing pressure, yet contents of almost all major gin senosides were higher than control (no-puffed). On the other hand, ginsenoside Rg3 were produced after puffing suggesting that chemical structure of some ginsenosides might be altered during the puffing process. These results indicate that puffing can increase the extraction yield and crude saponin contents and it could influence the ginsenoside composition.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2002.11a
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• pp.502-511
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• 2002

컴퓨터의 기술적 발전은 사회 여러 분야에 막대한 영향을 끼쳤다. 그중 악보 인식분야에도 커다란 영향을 주었다 그러나, On-line 상에서 그린 악보를 실시간으로 정형화된 악보형태로 변환하는 처리에 대한 연구가 미흡하여 이에 대한 연구가 필요하다. 본 논문에서는 실시간으로 악보를 인식하고, 사용자의 편의를 도모하기 위해 DP(Dynamic Programming) 매칭법을 이용한 On-Line 악보인식에 관한 방법을 제안하였다. 본 연구에서는 실시간으로 입력되는 악상기호를 인식하기 위해, 가장 유효한 정보인 악상 기호내의 방향, x, y 좌표를 이용하여 벡터형태로 추출한 후 음표와 비음표(쉼표, 기타기호)의 두개의 그룹으로 나누어진 표준패턴과의 DP매칭을 통해 인식한다. 먼저 tablet을 통해 실시간으로 악상 기호를 입력할 때 생기는 x, y좌표를 이용하여, 펜의 움직임에 대한 16방향 부호화를 수행한다. 음표와 비음표를 구분하기 위한 시간을 줄이고자 16방향 부호화를 적용하치 않고 사사분면부호화를 적용한다. 음표를 약식으로 그릴 경우 음표 머리에 해당하는 부분의 좌표는 삼사분면에 분포하고, 폐곡선의 음표일 경우에는 좌표가 사사분면에 고르게 나타난다. 폐곡선을 제외한 음표의 머리는 폐곡선과 같은 조건이면서 입력받은 y좌표값들 중에서 최소값과 최대값을 구한 다음 2로 나눈 값을 지나는 y좌표의 개수가 임의의 임계값 이상이면 음표로 판단한다. 위 조건을 만족하지 않을 경우 비음표로 취급한다. 음표와 비음표를 결정한 다음, 입력패턴과 표준패턴과의 DP매칭을 통하여 벌점을 구한다. 그리고 경로탐색을 통해 벌점에 대한 각각의 합계를 구해 최소값을 악상기호로 인식 하였다. 실험결과, 표준패턴을 음표와 비음표의 두개의 그룹으로 나누어 인식함으로써 DP 매칭의 처리 속도를 개선시켰고, 국소적인 변형이 있는 패턴과 특징의 수가 다른 패턴의 경우에도 좋은 인식률을 얻었다.r interferon alfa concentrated solution can be established according to the monograph of EP suggesting the revision of Minimum requirements for biological productss of e-procurement, e-placement, e-payment are also investigated.. monocytogenes, E. coli 및 S. enteritidis에 대한 키토산의 최소저해농도는 각각 0.1461 mg/mL, 0.2419 mg/mL, 0.0980 mg/mL 및 0.0490 mg/mL로 측정되었다. 또한 2%(v/v) 초산 자체의 최소저해농도를 측정한 결과, B. cereus, L. mosocytogenes, E. eoli에 대해서는 control과 비교시 유의적인 항균효과는 나타나지 않았다. 반면에 S. enteritidis의 경우는 배양시간 4시간까지는 항균활성을 나타내었지만, 8시간 이후부터는 S. enteritidis의 성장이 control 보다 높아져 배양시간 20시간에서는 control 보다 약 2배 이상 균주의 성장을 촉진시켰다.차에 따른 개별화 학습을 가능하게 할 뿐만 아니라 능동적인 참여를 유도하여 학습효율을 높일 수 있을 것으로 기대된다.향은 패션마케팅의 정의와 적용범위를 축소시킬 수 있는 위험을 내재한 것으로 보여진다. 그런가 하면, 많이 다루어진 주제라 할지라도 개념이나 용어가 통일되지 않고 사용되며 검증되어 통용되는 측정도구의 부재로 인하여 연구결과의 축적이 미비한 상태이다. 따라서, 이에 대한 재고와 새로운 방향 모색이 필요하다고 사료된다.로 사료되며, 임신관련 cytokine에 대한 다양한 연구가 요구되고 있다.₂/Hf(Variable)/Si 계에서 HfO₂ 박막이 Si 기판위에 직접 증착되면, 순수 HfO₂ 박막의

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.343-347
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• 2008

There are two kind of system in hotel for evaluating management. the first is infra system, for example Front management system - reservation system, C/I, C/O system, POS system , web system, call center management -, Back office system, interface system, and so on which manage direct control for hotel, and next is strategic system, for example BSC , CS . which is supporting hotel management. The purpose of this study was to find using the Balanced Scorecard to evaluate hotel management perfomance. Management performance is based on productivity, quality, time, effect, and responsiveness. Hotel economic value is not equal visual asset which is measured financial value. It is include hotel brand, image, customers who have good loyalty, employees who give customers special service, and systems which was affected by internal process. In conclusion, innovation, growth, internal system process, empioyee and customer have effect hotel performance. Therefore hotel has to know non-financial performance which has positively relate to financial performance.

• Journal of Applied Biological Chemistry
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• v.57 no.1
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• pp.73-81
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• 2014

The present study was carried out to assess exposure and risk to thiophanate-methyl wettable powder for agricultural worker during mixing/loading and application with power sprayer in green pepper, cucumber and apple fields. Dermal exposure was measured with patches, gloves, socks and masks, while inhalation exposure was evaluated with personal air pump and solid sorbent. Those methods were full validated before experiment. During mixing/loading, dermal exposure amount in green pepper, cucumber and apple fields was $24.0{\pm}6.7$, $4.5{\pm}1.5$ and $18.5{\pm}0.6mg$, corresponding to mean 0.007, 0.001 and 0.005% of prepared active ingredient, respectively. The major exposed part for mixer/loader was hands (78-92%). Dermal exposure amount for applicator in green pepper, cucumber and apple fields was $84.9{\pm}14.0$, $34.0{\pm}20.8$ and $30.7{\pm}9.1mg$, corresponding to mean 0.024, 0.016 and 0.013% of applied active ingredient, respectively. The main body parts of exposure in apple field were hands, while thighs and shins in other fields. Inhalation exposure amount in green pepper, cucumber and apple fields was $1.5{\pm}2.2$, $52.7{\pm}48.9$ and $4.0{\pm}4.9{\mu}g$ during mixing/loading and $0.2{\pm}0.1$, $23.2{\pm}12.4$ and $0.4{\pm}0.6{\mu}g$ for applicator, respectively. These results were suggested that main factors affecting dermal exposure were contact frequency to the plants, foliage density, hygienic behavior, work type, and working environment, while inhalation exposure was affected mainly by working environment, especially wind. In risk assessment, margin of safety for thiophanate-methyl in all cases was over 1. However, during application in green pepper field, margin of safety was close to 1.

• Korean Journal of Medicinal Crop Science
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• v.4 no.1
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• pp.78-85
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• 1996

The effects of growth regulators, sucrose and gelling agents were investigated to increase the efficiency of the callus growth and plant regenerarion in tissue culture of Angelica koreana Max. The fresh weight and dry weight of subcultured callus was highest in MS medium supplemented with 1 mg/l 2,4-D. Callus growth was excellent in 2% sucrose, but it was inhibited in propotion to sucrose content. Effect of gelling agents on callus growth was highest on 1.2% agar and 0.4% Gelrite medium, respectively. The browning of callus was protected on the media supplemented with 10 mg/l ABA and 5 or 10 mg/l $AgNO_3$. In the callus induction and growth from the peduncle of immature inflorescence, 2,4-D was more effective than NAA, and the frequency of callus induction was highest as 81.7% in 2 mg/l 2,4-D. Plant was not regenerated from the callus derived from young leaf. Somatic embryos were developed from the surface of callus drived from the peduncle of immature inflorescence in the medium containing 0.5 mg/l 2,4-D, 1 mg/l kinetin, 5 mg/l ABA and 5 mg/l $AgNO_3$. Plants were developed from the matured somatic embryos in the medium supplemented with 0.2 mg/l 2,4-D and 1 mg/l kinetin.

• Journal of Animal Environmental Science
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• v.14 no.3
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• pp.159-166
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• 2008

This research was carried out to test and analyze capacity of the long distance sprayer fan in large livestock farmhouses. Long distance sprayer was manufactured to be able to spray a lot of water, which was a solvent for agricultural chemicals and black dye with the maximum spraying distance of 140 m and the effective spraying distance of 100 m. The spraying quantity and the distance were measured the intensity values of images within A4 papers, which absorbed the agricultural chemicals by spraying by binary image processing. These A4 papers were fixed upon the height of 1 m from soil ground at regular 10 m interval. After the A4 papers were collected and analyzed the intensity values of gray level. Gray level was ranged from 0 to 255, where 0 was black and 255 was white. A4 paper was fallen down from the stick at 10 m distance, because there were too large amount of sprayed water with black dye. Also, the paper showed low gray level at distance 30 m because of dropping lots of black water. The intensity value of gray level was showed almost less than 200 on the A4 papers between the distance 20 m and 100 m, which meant equality of spraying quantity. Additionally, it was possible to spay agricultural chemicals of until 180 m. Throughout this research, long distance sprayer could apply for preventing hoof-and-mouth disease in large livestock farmhouses.

• Sleep Medicine and Psychophysiology
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• v.19 no.1
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• pp.11-17
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• 2012

Objective: Among various methods developed to quantitatively explore electroencephalograms (EEG), we focused on a wavelet method that was known to yield robust results under nonstationary conditions. The aim of this study was thus to introduce the wavelet method and demonstrate its potential use in clinical sleep studies. Method: This study involved artificial EEG specifically designed to validate the wavelet method. The method was performed to obtain time-dependent spectral power and phase angles of the signal. Synchrony of multichannel EEG was analyzed by an order parameter of the instantaneous phase. The standard methods, such as Fourier transformation and coherence, were also performed and compared with the wavelet method. The method was further validated with clinical EEG and ERP samples available as pilot studies at academic sleep centers. Result: The time-frequency plot and phase synchrony level obtained by the wavelet method clearly showed dynamic changes in the EEG waveforms artificially fabricated. When applied to clinical samples, the method successfully detected changes in spectral power across the sleep onset period and identified differences between the target and background ERP. Conclusion: Our results suggest that the wavelet method could be an alternative and/or complementary tool to the conventional Fourier method in quantifying and identifying EEG and ERP biomarkers robustly, especially when the signals were nonstationary in a short time scale (1-100 seconds).