• Journal of Navigation and Port Research
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• v.31 no.5 s.121
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• pp.415-420
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• 2007

In this paper, we have designed and fabricated a new type of bandpass-filter that used rectangular ring and interdigital capacitive feeding-structure. The filter is applied the modified rectangular ring and interdigital capacitive feeding-structure in patch, which reduce rho size of filter and IEEE 802. 11 correspond to wireless LAN domain(2.45GHz and 5.2GHz) for operating. As a result, the design and fabrication process of the filter become simple and the size of it is reduced more than 60% compared with RF filter are available conventional PEMBF(Parallel Edge-coupled Microstrip Bandpass Filter) of accounted circuit by minimum stage, measurement result of fabricated filter, center frequence is down 2.408GHz and 5.075GHz. input return loss is -39.169dB at 2.408GHz, -40.922dB at 5.075GHz. insertion loss is -0.437dB at 2.408GHz, -1.669dB at 5.075GHz.

• Tuberculosis and Respiratory Diseases
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• v.49 no.2
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• pp.246-252
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• 2000

Lymphangioleiomyomatosis(LAM) is a rare disease of unknown etiology that occurs mainly in woman in her reproductive age. We recently experienced two cases of bilateral diffuse cystic lesion of the lung on chest X-ray and HRCT. The first case, a 26-year-old female, who had been diagnosed with tuberous sclerosis by the presence of clinical manifestation such as mental retardation, bilateral renal angiomyolipoma, adenoma sebaceum and generalized seizure, was admitted due to a recently developed hemoptysis. Chest PA showed diffuse ground-glass opacity with radiolucent cystic lesions of various sizes on both lung fields. HRCT showed innumerable small cystic lesions with suspicious diffuse ground-glass opacity on both lung fields The second case, a 30-year-old fema1e was admitted due to dyspnea and spewing of blood-tinged sputum for 2 weeks, shortly after delivery. Chest PA showed diffuse reticular and ground-glass opacities on both lung field. HRCT showed multiple well-defined and relatively uniform size air cysts with a uniform wall thickness on entire both lung fields, with small amount of right pleural effusion. By thoracoscopic lung biopsy she was diagnosed with pulmonary lymphangioleiomyomatosis. We report these cases with a brief review of the literatures.

• Structural Engineering and Mechanics
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• v.50 no.5
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• pp.589-603
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• 2014

Expressions for determining the value of the impact force as reported in the literature and incorporated into code provisions are essentially quasi-static forces for emulating deflection. Quasi-static forces are not to be confused with contact force which is generated in the vicinity of the point of contact between the impactor and target, and contact force is responsible for damage featuring perforation and denting. The distinction between the two types of forces in the context of impact actions is not widely understood and few guidelines have been developed for their estimation. The value of the contact force can be many times higher than that of the quasi-static force and lasts for a matter of a few milli-seconds whereas the deflection of the target can evolve over a much longer time span. The stiffer the impactor the shorter the period of time to deliver the impulsive action onto the target and consequently the higher the peak value of the contact force. This phenomenon is not taken into account by any contemporary codified method of modelling impact actions which are mostly based on the considerations of momentum and energy principles. Computer software such as LS-DYNA has the capability of predicting contact force but the dynamic stiffness parameters of the impactor material which is required for input into the program has not been documented for debris materials. The alternative, direct, approach for an accurate evaluation of the damage potential of an impact scenario is by physical experimentation. However, it can be difficult to extrapolate observations from laboratory testings to behaviour in real scenarios when the underlying principles have not been established. Contact force is also difficult to measure. Thus, the amount of useful information that can be retrieved from isolated impact experiments to guide design and to quantify risk is very limited. In this paper, practical methods for estimating the amount of contact force that can be generated by the impact of a fallen debris object are introduced along with the governing principles. An experimental-calibration procedure forming part of the assessment procedure has also been verified.

• Journal of the Korean Geotechnical Society
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• v.37 no.11
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• pp.23-36
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• 2021

In this paper, the effect of shear rate on internal friction angle and unconfined compressive strength of non-cemented and cemented sand was investigated. A dry Jumunjin sand was prepared at loose, medium, and dense conditions with a relative density of 40, 60 and 80%. Then, series of direct shear tests were conducted at shear rates of 0.32, 0.64, and 2.54 mm/min. In addition, a cemented sand with cement ratio of 8% and 12% was compacted into a cylindrical specimen with 50 mm in diameter and 100 mm in height. Unconfined compression tests on the cemented sand were performed with various shear rates such as 0.1, 0.5, 1, 5 and 10%/min. Regardless of a degree of cementation, the unconfined compressive strength of the cemented sand and the angle of internal friction of the non-cemented sand tended to increase as the shear rate increased. For the non-cemented sand, the angle of internal friction increased by 4° at maximum as the shear rate increased. The unconfined compressive strength of the cemented sand also increased as the shear rate increased. However, its increasing pattern declined after the standard shear rate (1 mm/min). A discrete element method was also used to analyze the crack initiation and its development for the cemented sand with shear rate. Numerical results of unconfined compressive strength and failure pattern were similar to the experimental results.

• Journal of Sericultural and Entomological Science
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• v.41 no.1
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• pp.20-28
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• 1999

Color qualities investigated on the basis of Munsell code and Korean standard color code for the cocoons from various strain of mulberry silkworm, Bombyx mori. 16 of different color qualities were identified from 21 of original silworm strains, and determinated international name with the revision of Korean color name for cocoon. The various cocoon color confirmed on the sphere from 567 to 593 nm wavelength, 78% of those located at the region about 580 nm (575~584) of sensitive "color difference limen". Y gene engaged broad ranges of wavelength (575~593 nm) in the color expression, by contrast with other genes of Pk (593 nm), F (584~593), Grc and relative G group (567~570 nm), on the transmission of carotenoid or flavonoid color substance. YC gene expression by original silk worm strain was also distinguished by those variation of specific yellow than other colors from Grc, GaGb, Gc, and YPkF. Appearance of chrome yellow cocoon was dominant than other yellow in the cross among vivid yellow group. F1 of pin${\times}$green produced the cocoon of yellow such as "additive mixture" as color light, however, most of the hybrid between yellow cocoon showed the color similar to "subtractive mixture" as a mixture of dyestuff. Hybrid cocoons among yellow or green colors were decreased their hue, value, and chroma, than those of parent. Diallel cross among the strain of various green cocoon suggest the existence of Grc, Ga, Gb, Gc genes. Cream colored cocoon of B. mandarina was differed from other yellow cocoon of Bobyx mori B. mori. Y$^A$ with Ymc showed the similar role of Y with C, therefore, segregated yellow cocoon from the B. mori${\times}$B. mandarina (+$^YC/Y^AYmc$). YC expression of $Y^AY$mc genes might be suppressed by deficiency of outer layer sericin on the middle division of silk giand in the B. mandarina.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.2
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• pp.135-142
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• 2011

This experiment was carried out to compare the growth characteristics and forage productivity between Italian ryegrass (Lolium multiflorum Lam.) and Oats (Avena sativa L.) sown in early spring on trial field of Grassland and Forages Division, National Institute of Animal Science, RDA, Cheonan and Jeollanam-do Agricultural Research and Extension Services, Naju in 2007 and 2008. Varieties used were Swan and Foothill in early- and late-maturing Oats, and Kospeed and Hwasan 101 in early- and late-maturing Italian ryegrass, respectively. In early-maturing variety, heading date of Swan was 14 May that was earlier one day than that of Kospeed. Plant length of Swan was 92cm that was longer 4cm than that of Kospeed. Average dry matter (DM) yield of 3 trial regions was not significantly different between Kospeed (6,809 kg/ha) and Swan (6,756 kg/ha) but DM yield of Italian ryegrass Hwasan 101 was less 35% than that of Swan. Average total digestible nutrient (TDN) yield of 3 trial regions was not significantly different between Kospeed (4,240 kg/ha) and Swan (4,162 kg/ha). In paddy cultivation of Naju, TDN yield of Kospeed was 4,154 kg/ha that was more 45% than that of Swan. Forage feed value was similar Kospeed to Swan in early maturing variety. Considering TDN yield and feed value of forage, early-maturing variety of Italian ryegrass was effective for spring-sown cultivation and suitable for forage production on paddy in southland of Korea.