• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 춘계학술대회논문집
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• pp.888-893
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• 2004

This paper proposed a dual actuator using bimorph PZT for information storage device based on prove array NSOM(Near-field Scanning Optical Microscopy). The gap between the media and the optical head should be maintained within the optical tolerance. Therefore, a new actuator having high sensitivity is required. Bimorph PZT, which has fast access time and high sensitivity characteristic, is suitable for this precise actuating system. This paper is focused on derivation of mathematical model of dual bimorph PZT actuator and control algorithm. Hamilton's principle was used for mathematical model. The model is verified by FEA(Finite Element Analysis), and compared with experimental results. Different control algorithms were used f3r two bimorph PZT actuating same direction and opposite direction. The gap between recording media and optical head was controlled within 20nm in experiment.

• 한국자동차공학회논문집
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• 제5권3호
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• pp.147-158
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• 1997

This paper presents the analysis technique and procedure of main engine components-cylinder block, cylinder liners, gasket and cylinder head-using the finite element method, which aims to assess mainly the potential of lower oil consumption in a view point of engine design and to decide subsequently the accuracy of engine design which was done. The F.E. model of an engine section consisting of one whole cylinder and two adjacent half cylinders is used, whereby the crankcase is cut off at the block bottom deck. By means of a 3-dimensional F.E. model-including cylinder block, liners, gasket, cylinder head, bolts and valve seat rings as separate parts a linear analysis of deformations and stresses was performed for three different loading conditions;assembly, thermal and gas loads. For the analysis of thermal boundary conditions also the temperature field had to be evaluated in a subsequent step.

• Parasites, Hosts and Diseases
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• 제57권5호
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• pp.499-504
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• 2019

Head-lice infestation, pediculosis capitis, remains a public-health burden in many countries. The widely used first-line pediculicides and alternative treatments are often too costly for use in poor socio-economic settings. Ivermectin has been considered an alternate treatment for field practice. This study was composed of 2 parts, a cross-sectional survey and an intervention study. The main objectives were to determine the prevalence and potential factors associated with head-lice infestation, and to evaluate the effectiveness and safety of oral ivermectin administration. A community-based cross-sectional survey was conducted among 890 villagers in rural areas along Thai-Myanmar border. Females with infestations were eligible for the intervention study, and 181 participated in the intervention study. A post-treatment survey was conducted to assess acceptance of ivermectin as a treatment choice. Data analysis used descriptive statistics and a generalized-estimation-equation model adjusted for cluster effect. The study revealed the prevalence of head-lice infestation was 50% among females and only 3% among males. Age stratification showed a high prevalence among females aged <20 years, and among 50% of female school-children. The prevalence was persistent among those with a history of infestation. The major risk factors were residing in a setting with other infected cases, and sharing a hair comb. The study also confirmed that ivermectin was safe and effective for field-based practice. It was considered a preferable treatment option. In conclusion, behavior-change communication should be implemented to reduce the observed high prevalence of head-lice infestation. Ivermectin may be an alternative choice for head-lice treatment, especially in remote areas.

• 한국유기농업학회지
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• 제21권2호
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• pp.247-263
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• 2013

본 실험은 강원지방에서 유기 생우분과 유기 발효우분을 시용하여 밭토양에서 하계작물로 sorghum ${\times}$ sudangrass 교잡종과 동계작물로는 rye 단파구, rye+red clover 혼파구, 논토양에서 벼 '추청' 재배 후, rye 단파구, rye+hairy vetch 혼파구를 도입하였을 때, 각 초종과 작부조합의 건물생산성, 사료가치, 혼파효과 및 가축사육능력을 평가하여 강원지역에서 조사료 생산에 적합한 작부조합을 선정하고자 하였고, 결과를 요약하면 다음과 같다. 하계작물로 밭토양에서 sorghum ${\times}$ sudangrass 교잡종의 건물수량은 CCM150에서 15.12 ton/ha으로 많았으나, CM150과는 유의한 차이는 없었다. 조단백질 수량은 1차 예취에서 CCM150이 0.59ton/ha로 유의하게 많았고(p<0.05), 2차 예취에서는 CM150이 0.44ton/ha로 유의하게 많았다(p<0.05). $K_{CP}+K_{TDN}/2$ 값은 CCM 150이 7.76head/ha로 많았다. 논토양의 유기 생우분 시용구에서 볏짚의 건물수량은 4.95 ton/ha으로 화학비료 시용구의 4.84ton/ha보다 많았지만 유의한 차이는 없었다. 조단백질 함량은 화학비료 시용구의 볏짚이 4.09%로 유의하게 높았고(p<0.05), TDN 함량은 유기 생우분 시용구의 볏짚이 55.63%로 화학시용구의 볏짚 53.94%보다 유의하게 높았다(p<0.05). 유기 생우분 시용구에서 볏짚의 $K_{CP}+K_{TDN}/2$ 값은 연간 1.89head/ha였다. 동계작물로 밭토양의 rye+red clover 혼파구의 건물수량은 CCM100에서 4.36ton/ha로 많았으나, 다른 처리구와 유의한 차이가 없었다. Rye+red clover 혼파구의 조단백질 함량은 CCM100에서 7.33%로 높았으나 CM100에서 rye+red clover 혼파구의 7.19%와는 유의한 차이는 없었다. Rye+red clover 혼파구의 $K_{CP}$와 $K_{TDN}$ 값은 각각 2.32head/ha와 2.36head/ha로 다른 처리구보다 유의하게 많았다(p<0.05). 논토양에서는 rye+red clover 혼파구의 건물수량은 4.19ton/ha로 많았으나, rye 단파구와는 유의한 차이는 없었다. Rye+red clover 혼파구의 조단백질 함량과 TDN 함량은 각각 7.21%와 59.33%로 다른 처리구보다 유의하게 높았다(p<0.05). 이상의 결과로 볼 때, 강원지방에서 유기우분을 시용하여 조사료를 생산할 경우 밭토양에서는 sorghum ${\times}$ sudangrass 교잡종을 재배한 후 rye+red clover의 혼파가, 논토양에서는 벼 재배 후 rye+hairy vetch를 혼파하는 작부조합이 생산성, 사료가치 및 가축사육능력을 높이는데 우수하였다고 판단된다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2005년도 창립60주년 기념 추계 학술대회
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• pp.99.1-99.1
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• 2005

• Journal of Photoscience
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• 제2권2호
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• pp.95-98
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• 1995

The photodimers with cyclobutane rings and C$_2$ symmetry, derived from coumarin (syn, head to tail and anti, head to head) have been calculated by PM3-UHF-CI and Molecular Mechanics force field. The photocycloaddition to coumarin and 5,7-dimethoxycoumarin(DMC) dimers were deduced to be formed by their preferable frontier orbital interactions and via more stable cycloaddition by the C$_3$, C$_4$ bond. These results are consistent with the coumarin dimer model that the theoretical C$_4$-photocyclodimer of coumarin is predicted much more than the experimental C$_4$-photocyclodimer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1428-1429
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• 2008

In this study the formula of electromagnetic field s by dipole antenna theory were applied to 3 phase power lines and effect of over-head earth lines was calculated and analyzed.

• Journal of Electrical Engineering and Technology
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• 제11권6호
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• pp.1744-1753
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• 2016

The main purpose of this article is a complex hyperthermia applicator system design for treatment of head and neck region. The applicator system is composed of four waveguides with a stripline horn aperture and circular water bolus. The specific absorption rate (SAR) and temperature distribution from this applicator in various numerical phantom models was investigated. For used targets, the treatment planning based on the optimization process made through the SEMCAD X software is added to show the steering possibilities of SAR and thereby temperature distribution. Using treatment planning software, we proved that the SAR and temperature distribution can be effectively controlled (by amplitude and phase changing) improving the SAR and temperature target coverage approximately by 20 %. For the proposed applicator system analysis and quantitative evaluation of two parameters 25 % iso-SAR and $41^{\circ}C$ iso-temperature contours in the treatment area with the respect to sensitive structures in treatment area were defined. To verify our simulation results, the real measurement of reflectivity coefficient as well as the temperature distribution in a homogenous phantom were performed.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.505-508
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• 2006

An electrostatic ink jet head can be used for manufacturing processes of large display systems and printed circuit boards (PCB) as well as inkjet printers because an electrostatic field provides an external force which can be manipulated to control sizes of droplets. The existing printing methods such as thermal bubble and piezo inkjet heads have shown difficulties to control the ejection of the droplets for printing applications. Thus, the new inkjet head using the electrostatic force has been proposed in this study. In order to prove the theory of the developed electrostatic ink jet head, the applicable and basic theory has been studied using distilled water and water with sodium dodecyl surfate (SDS). Also, a numerical analysis has been performed to calculate the intensity of the electrostatic field using the Maxwell's equation. Furthermore, experiments have been carried out using a downward glass capillary with outside diameter of $500{\mu}m$. The gravity, surface tension, and electrostatic force have been analyzed with high voltages of 0 to 5kV. It has been observed that the droplet size decreases and the frequency of the droplet formation and the velocity of the droplet ejection increase with increasing the intensity of the electrostatic field. The results of the experiments have shown good agreement with those of numerical analysis.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2007년도 추계학술대회
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• pp.128-133
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• 2007

An electrostatic inkjet head can be used for manufacturing processes of large display systems and printed circuit boards (PCB) as well as inkjet printers because an electrostatic field provides an external force which can be manipulated to control sizes of droplets. The existing printing methods such as thermal bubble and piezo inkjet heads have shown difficulties to control the ejection of the droplets for printing applications. Thus, the new inkjet head has been proposed using the electrostatic force. A numerical analysis has been performed to calculate the intensity of the electrostatic field using the Maxwell's equation. Also, experiments have been carried out to investigate the droplet movement using a downward capillary with outside diameter of $500{\mu}m$. Gravity, surface tension, and electrostatic force have been analyzed with high voltages for a drop-on-demand ejection. It has been observed that the droplet size decreases and the frequency of the droplet formation and the velocity of the droplet ejection increase with increasing the intensity of the electrostatic field using high-speed camera.