• YAKHAK HOEJI
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• v.13 no.4
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• pp.125-138
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• 1969

The absorptions of aminopyrine, molecular compounds of aminopyrine and mixed compounds of aminopyrine were studies in the small intestine of rats (in situ). The molecular compounds of aminopyrine were more absorbed than aminopyrine and mixed compounds of aminopyrine were less absorbed than aminopyrine in small intestine of rats. The appearent permeability coefficients and the absorption velocity constants of the molecular compound of aminopyrine-barbital were highest and the orders of decreasing in values of permeability coefficients and the absorption velocity constants of the other molecular compounds are as follows: Aminopyrine-secobarbital, Aminopyrine-phenobarbital Aminopyrine-amobarbital, Aminopyrine-cyclobarbital Aminopyrine-allobarbital. The orders of decreasing in values of the appearent permeability coefficients and the absorption velocity constants of the mixed compounds of aminopyrine are as follows: Aminopyrine secobarbital, Aminopyrine allobarbital Aminopyrine cyclobarbital, Aminopyrine amobarbital Aminopyrine phenobarbital, Aminopyrine barbital. The relative absorption rates of aminopyrine, molecular compounds of aminopyrine and the mixed compounds of aminopyrine by the goldfish method and the partition coefficients were correlative to the values of circulation method.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.2
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• pp.234-240
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• 2006

Al film(135.5 nm thick) with Pd film(39.6 nm thick) on the top of it was made by thermal evaporation method. Hydrogen absorption of Al/Pd film was measured by quartz crystal microbalance(QCM) method at room temperature. The sample was activated by hydrogen absorption and desorption cycling at room temperature. Hydrogen was introduced into the film by increasing hydrogen gas pressure step by step up to 640 torr at room temperature. Hydrogen concentration reached up to 25% at $5{\sim}10$ torr. But at high pressure the concentration decreased. This strange tendency was not understood yet. Further study is needed to find out the mechanism of hydrogen absorption in Al in Al/Pd film.

• Journal of Magnetics
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• v.11 no.2
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• pp.90-94
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• 2006

A finite-element method is used to analyze loss generation and electromagnetic noise absorption characteristics of a coplanar waveguide transmission line integrated with a magnetic thin film. Parameters used in the analysis are the electrical resistivity of the magnetic layer and the thickness of both magnetic and insulating layers. The results indicate that L-C resonance is the main loss mechanism of the electromagnetic noise absorption.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.762-765
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• 2005

The absorption materials have been used to enhance the performance of a noise barrier and improve the room acoustics. In this study, 6 products of absorptive materials generally used in Korea were chosen, and their absorption performance were tested in various conditions, that is, it was measured while changing thickness, density and air gap in their back, and measured with or without facing on their face. Finally, the absorption coefficients were compared by reverberation and impedance tube method.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1723-1726
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• 2008

In recent years, there has been a remarkable progress in the development of the fiber optic sensors for the detection of various chemicals. Fiber optic sensors have the advantages of very small size, flexibility and low cost. The fiber optic sensors employing different optical or spectroscopic phenomena have been reported such as bulk absorption, optical reflectance, fluoresces and energy transfer. In this study, the effect of nanoparticle concentration in liquid upon light absorption and scattering was studied using extrinsic fiber optic method. For the evaluation, we used Red (650 nm) and Blue (430 nm) light sources which are coupled through the standard cuvette using optical fiber to detector. The experiments are carried out with Polystyrene latex (400 - 800 nm), and Silicon (35 - 110 nm) nanoparticles suspended in Isopropanol. Differences in light absorption and scattering depending on nanoparticle concentration and type are discussed. This method may be useful to study nanoparticles properties for various application and research.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.5 s.122
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• pp.373-378
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• 2007

Today, the use of the sound absorptive material is increasing to improve the room acoustics in the auditorium and music hall, etc. Usually, the sound absorption materials have been used to enhance the performance of a noise barrier and improve the room acoustics in construction site. Generally, the sound absorbtion coefficients are the most important factor reflecting the sound absorbtion performance. There are two methods to measure the sound absorption coefficient. The first one is the reverberation room method, and the second is the impedance tube method. In this study, we measure the sound absorbtion coefficients using these two methods, and then we compared the results of the sound absorbtion coefficients to look into the difference of results between reverberation room method and impedance tube method. Also we compared the results of the sound absorbtion coefficients with respect to the size of sample and the volume of reverberation room. From the experiment, we could see that the sound absorbtion coefficients are measured equally for different sample size. But the sound absorbtion coefficients are measured differently according to test methods and test conditions.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.200-203
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• 2008

The objective of this study is to produce the $CO_2$ (carbon dioxide) absorption map using KOMPSAT-2 imagery. For estimating the amount of $CO_2$ absorption, the stand biomass of forest was estimated with the total weight, which was the sum of individual tree weight. Individual tree volumes could be estimated by the crown width extracted from KOMPSAT-2 imagery. In particular, the carbon conversion index and the ratio of the $CO_2$ molecular weight to the C atomic weight, reported in the IPCC (Intergovernmental Panel on Climate Change) guideline, was used to convert the stand biomass into the amount of $CO_2$ absorption. Thereafter, the KOMPSAT-2 imagery was classified with the SBC (segment based classification) method in order to quantify $CO_2$ absorption by tree species. As a result, the map of $CO_2$ absorption was produced and the amount of $CO_2$ absorption was estimated by tree species.

• Journal of the Optical Society of Korea
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• v.9 no.4
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• pp.131-134
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• 2005

We have proposed a method to calculate the absorption coefficients for the bound-to-continuum transitions in a strong biased quantum-well infrared photodetector. We have applied this method to a manufactured sample of typical device parameters, and obtained good agreements with experiments. The absorption coefficients evaluated are up to 5,700/cm at some particular operating conditions. We have also been able to make a qualitative explanation for the bias dependence of response.

• YAKHAK HOEJI
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• v.29 no.3
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• pp.111-116
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• 1985

Effect of sodium-5-methoxysalicyclate (5MSA-Na) on the absorption of cefmetazol (CMZ) was studied in rectum and duodenum of rats via in situ loop method. Effect of 5MSA-Na on the absorption of CMZ showed markedly different results in rectum and duodenu. Penetration of 5MSA-Na was greater in rectum than in duodenum and water-transfer was markedly increased in duodenum.

• The Journal of the Acoustical Society of Korea
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• v.37 no.4
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• pp.181-187
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• 2018

In this paper, sound absorption of micro-perforated elastic plates installed in an impedance tube of a circular cross-section is discussed using an analytic method. Vibration of the plates and sound pressure fields inside the duct are expressed in terms of an infinite series of modal functions, where modal functions in the radial direction is given in terms of the Bessel functions. Under the plane wave assumption, a low frequency approximation is derived by including the first few plate modes, and the sound absorption coefficient is given in terms of an equivalent impedance of a single surface. The sound absorption coefficient using the proposed formula is in excellent agreement with the result by the FEM (Finite Element Method), and shows dips and peaks at the natural frequencies of the plate. When the perforation ratio is very small, the sound absorption coefficient is dominated by the vibration effect. However, when the perforation ratio reaches a certain value, the sound absorption is mainly governed by the rigid MPP (Micro-Perforated Plate), while the vibration effect becomes very small.