• Explosives and Blasting
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• v.22 no.2
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• pp.33-43
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• 2004

The six grades weathering system is normally used in weathered rock classification. In this study. fresh and weathered rock block of grade I to V were sampled in Jang-soo ana but samples of the grade VI was omitted from this study. The variation quantities of chemical weathering indices with weathering degree are smaller than those of physical and mechanical properties. Increase of Weathering degree is well indicated by physical and mechanical properties such as strength, hardness, ultrasonic velocity and slake durability result. Especially, absorption and porosity ratio is a good indicator. As weathering proceeds. a number of the cracks affect the rock deformation. Therefore, stress-strain curves of weathered rocks in unconfined state are quite different from ones of fresh rocks.

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.1
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• pp.37-45
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• 2012

Purpose: The change of alignment between RGP lens and cornea according to the lens design was investigated by comparing the areas of fluorescein pattern in central and peripheral regions analyzed by astigmatic degree and corneal type when spherical and aspherical RGP lenses fitted in alignment. Methods: The fluorescein patterns of 90 eyes (19-30 years, $25.12{\pm}3.52$) having with-the-rule astigmatism were analyzed after spherical and aspherical RGP lenses fitted in alignment. Then, their fluorescent areas in central and peripheral regions were calculated and compared for the quantitative evaluation. Results: The case showing concordant base curve between spherical and aspherical RGP lenses in alignment fitting was 72% however, the possibility to have same base curves between spherical and aspherical RGP lenses in alignment fitting was to be less in the case of symmetric bowtietyped cornea and high astigmatism. The fluorescent area in peripheral region of aspherical RGP lens in alignment fitting was smaller than it of spherical RGP lens. Peripheral fluorescent areas in both RGP lenses decreased according to the increase of astigmatic degree and peripheral area in symmetric bowtie-typed corea was smaller than round-typed cornea's peripheral area. In the case of same astigmatic degree, peripheral fluorescent area of aspherical RGP lens was smaller in both corneal types. Conclusions: The results above suggest the changing degree in the alignment between RGP lens and cornea can be varied according to lens design, corneal astigmatism and corneal type. Thus, the results obtained from the quantitative analysis of the alignment between lens design and cornea may be used as the basic information about the establishment of guidelines for RGP lens fitting, the development of proper lens design, and different tear volume in partial regions.

• Korean Journal of Animal Reproduction
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• v.10 no.2
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• pp.211-217
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• 1986

This experiment was conducted to determine the effect of FSH on in vitro maturation and in vitro fertilizing ability of oocytes recovered from normal follicles of different sizes in superovulated rabbits. Follicular oocytes recovered were cultured in modified Ham's F12 medium containing 0, 0.1, 1.0 and 10$\mu\textrm{g}$ FSH/ml for 18 hours and investigated the degree of cumulus cells expansion and nuclear maturation, which were fertilized with in vivo capacitated rabbit sperm. 1. The number of normal follicles<1.5mm, 1.6 to 2.5mm and> 2.5mm in diameter at 16 to 18hrs after HCG administration was 4.8 (38.8%), 5.5(45.4%) and 3.3(15.8%), respectively. Average percent of oocytes recovered was 69.7% and larger follicles tended to have a higher percent, recovery rate than smaller follicles. 2. The degree of cumulus expansion in medium containing 0.1$\mu\textrm{g}$ FSH/ml was similar to that of control, but markedly decreased under the level of above 1$\mu\textrm{g}$ FSH/ml. The proportions of oocytes which reached the second meiotic metaphase were 57.1, 61.5, 43.8 and 45.0% in medium containing 0, 0.1, 1.0 and 10$\mu\textrm{g}$ FSH/ml, respectively. Oocytes from larger follicles showed a higher nuclear maturation than that from smaller follicles. 3. In vitro fertilization rate of oocytes matured under 1$\mu\textrm{g}$ FSH/ml was slightly, not significant, higher than that of others. 4. Progesterone level in follicular fluid was about 67 to 71ng/ml with no difference in follicular sizes and estradiol-17$\beta$ level was under 25pg/ml.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.8
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• pp.701-706
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• 2014

In these days, there have been numerous researches on nano and micro satellites under the slogan of "Faster, Smaller, Better, Cheaper". Since optical structure occupies large portion of satellite volume, research on deployable optical structure gains great attention to reduce total volume of the satellite. In this paper, we establish the requirement of deployable optical structure based on specification of conventional optical structure and propose two candidate mechanisms which can satisfy the degree of deployment precision. Then, in order to evaluate the degree of deployment precision, we carry out kinematic analysis on de-space among tilt, de-space and de-center which influences optical characteristic of a satellite.

• Water for future
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• v.26 no.3
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• pp.137-148
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• 1993

A hybrid finite difference method for the longitudinal dispersion equation was developed. The method is based on combining the Holly-Preissmann scheme with the fifth-degree Hermite interpolating polynomial and the generalized Crank-Nicholson scheme. Longitudinal dispersion of an instantaneously-loaded pollutant source was simulated by the model and other characteristics-based numerical methods. Computational results were compared with the exact solution. The present method was free from wiggles regardless of the Courant number, and exactly reproduced the location of the peak concentration. Overall accuracy of the computation increased for smaller value of the weighting factor, $\theta$ of the model. Larger values of $\theta$ overestimated the peak concentration. Smaller Courant number gave better accuracy, in general, but the sensitivity was very low, especially when the value of $\theta$ was small. From comparisons with the hybrid method using the third-degree interpolating polynomial and with split-operator methods, the present method showed the best performance in reproducing the exact solution as the advection becomes more dominant.

• 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 the Korean Society of Clothing and Textiles
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• v.27 no.1
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• pp.18-28
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• 2003

The purpose of this study is to provide total data of real body-type and self-evaluation about it. The subjects were 614 middle-aged women between 35 and 59 years old. Data were collected through measurement and a questionnaire survey on self-evaluation. The results of self-evaluation of body are as follows; 1. As the result of the recognition degree analysis, people consider themselves thicker, shorter or smaller than what they really we, regardless of ages and types. In addition, the women of younger group rather than the women of older group consider themselves bigger/thicker and shorter than what they really are. They think that the items of waist girth, abdominal girth, hip girth, upper arm girth. and thigh girth are thicker than the other items, however, among girth items the size of bust girth is smaller than the other items. The women of the late middle-aged group consider their somatotype thicker/bigger and shorter than the women of the early middle-aged group do. 2. As the result of body cathexis for each part, women in general rum out themselves not to be satisfied with their body parts, regardless of ages and types. Particularly, they are not satisfied with abdominal girth, weight, hip girth. According to the age bracket, the women in the older group are more satisfied than the women of younger group in terms of their body. According to somatotype, women in tall and slim groups are more satisfied with their body. The women of the early middle-aged group turn out not to be satisfied with girth items while the women of the late middle-aged group are not satisfied with length items.

• Journal of Korea Water Resources Association
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• v.46 no.5
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• pp.439-447
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• 2013

The applicability of the parameter map of the Modified Bartlett-Lewis Rectangular Pulse (MBLRP) model for the Korean Peninsula was assessed from the perspective of flood prediction. The design rainfalls estimated from the MBLRP model were smaller than those from observed values by 5% to 40%, and the degree of underestimation of design rainfall increases with the increase of the recurrence interval of the design rainfall. The design floods at a virtual watershed estimated using the simulated rainfall time series based on MBLRP model were also smaller than those derived from the observed rainfall time series by 20% to 45%. The degree of underestimation of design flood increases with the increase of the recurrence interval of the design flood.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.1
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• pp.177-186
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• 2017

Recently, Autonomous vehicles are getting hot attention. Amazon, the biggest online shopping service provider is developing a delivery system that uses drones. This kinds of platforms are need accurate attitude information for navigation. In this paper, a structure design of AHRS using low-cost inertia sensor is proposed. To estimate attitudes a Kalman filter which uses a quaternion based dynamic model, bias-removed measurements from MEMS Gyro, raw measurements from MEMS accelerometer and magnetometer, is designed. To remove bias from MEMS Gyro, an additional Kalman filter which uses raw Gyro measurements and attitude estimates, is designed. The performance of implemented AHRS is compared with high price off-the-shelf 3DM-GX3-25 AHRS from Microstrain. The Gyro bias was estimated within 0.0001[deg/s]. And from the estimated attitude, roll and pitch angle error is smaller than 0.2 and 0.3 degree. Yaw angle error is smaller than 6 degree.

• Economic and Environmental Geology
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• v.17 no.1
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• pp.49-55
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• 1984

This paper describes three-dimensional (3-D) standard curves for conductive dipping buried bodies in induced polarization (IP) method. Dipole-dipole IP responses for the dipping bodies are calculated by the numerical modeling technique using an integral equation solution. Dip angles of the bodies are 0, 20, 45, 70 and 90 degrees, respectively. The horizontal (0-degree dip) and vertical (90-degree dip) bodies produce symmetrical patterns of IP responses. The dipping bodies of 20, 45 and 70 degrees, however, produce asymmertical patterns, with the highest IP contours dipping in the direction opposite to the bodies in pseudo-sections. The most remarkable asymmetrical pattern appears in the model of 20-degree dip. It is difficult to distinguish the body of 70-degree dip from that of 90-degree dip on the basis of dipole-dipole IP data. The IP pattern in pseudo-sections varies when the line moves away from the center of the body along strike, with the anomaly deeper and smaller in amplitude. IP maps seem to be more useful than IP pseudo-sections in predicting the location of target.