• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.329-334
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• 1992

Ultrasonic absorption was measured in bovine serum albumin (BSA) aqueous solution (50 g/l) in the frequency range from 100 kHz to 1600 MHz at neutral pH. Three experimental techniques were used to cover the wide frequency range : plano-concave resonator, conventional Bragg reflection, and high-resolution Bragg reflection methods. The absorption spectrum at neutral pH fitted the relaxation curve well using the distribution function of a mirror image of Davidson-Cole function. The relaxaition behavior was interpreted in terms of various degree of hydration of BSA molecules.

• Publications of The Korean Astronomical Society
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• v.11 no.1
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• pp.221-229
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• 1996

We have developed a measurement system with which harmful radio noise can be detected. It was designed to cover 1GHz band width centered at l.5GHz and 22.2GHz ($H_2O$ line).The system consists of pyramid horn antennas, receivers, equatorial tracking system, spectrum analyzer, and PC for the control of the servo and data taking. As a test of the system, the site of Taeduk Radio Astronomy Observatory (TRAO) was investigated to see if there is any harmful radio interference. It is found that in 22GHz band there is no significant radio noise, but there are identified and unidentified artificial radio signals in 1-2GHz range. However a simple calculation of radiation power shows that it is week enough not to affect the observations in TRAO.

• Advances in concrete construction
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• v.3 no.1
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• pp.15-37
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• 2015

Ongoing efforts for improved fracture toughness of engineered cementitious materials address the inherent brittleness of the binding matrix at several different levels of the material's geometric scale through the addition of various types of reinforcing fibers. Crack control is required for crack widths that cover the entire range of the grain size spectrum of the material, and this dictates the requirement of hybrid mixes combining fibers of different size (nano, micro, macro). Use of Carbon Nano-Tubes (CNT) and Carbon Nano-Fibers (CNFs) as additives is meant to extend the crack-control function down to the nanoscale where cracking is believed to initiate. In this paper the implications of enhanced toughness thus attained at the material nanostructure are explored, with reference to the global smeared constitutive properties of the material, through consistent interpretation of the reported experimental evidence regarding the behavior of engineered cementitious products to direct and indirect tension.

• Journal of Smart Tourism
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• v.1 no.1
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• pp.19-30
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• 2021

Smart tourism technologies are becoming ever more pervasive and an increasing number of destinations and hospitality establishments are investing in smart tourism initiatives. However, while governments and businesses around the world are aggressively pushing the smart tourism agenda forward, smart tourism research initiatives are still in their infancy and seem to not fully cover the whole spectrum of smart tourism-related issues and questions. This paper conducts a systematic review of existing smart tourism literature to determine the status quo of smart tourism research and to identify research gaps. Considering the steep growth of smart tourism initiatives starting at the beginning of this decade, this paper reviews publications on smart tourism over the last 8 years. All publications for which the keyword "smart tourism" appears in the title, keywords or abstract were included in the sample.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.41.3-41.3
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• 2019

Ices in interstellar environments are well traced mostly by their absorption features in the near- to mid-infrared spectrum. The infrared camera (IRC) aboard AKARI provides us the near-infrared spectroscopic data which cover $2.5-5.0{\mu}m$ with a spectral resolution of R ~ 120. Our AKARI spectroscopic survey of young stellar objects (YSOs), including low-luminosity protostars and background stars, revealed the absorption features of $H_2O$, $CO_2$, CO, and XCN ice components. We present near-infrared spectra of the observed targets and compare their ice abundances with those previously derived from various YSOs and the background stars behind dense molecular clouds and cores. In addition, we suggest possible science cases for SPHEREx, NASA's new near-infrared space observatory, based on the results from our AKARI IRC spectroscopic study.

• The Bulletin of The Korean Astronomical Society
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• v.46 no.1
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• pp.57.1-57.1
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• 2021

The icy mantles of interstellar grains are developed by the freeze-out of interstellar molecules and atoms onto grain surfaces. The ice molecules become more complex by surface chemistry induced directly by high energy photons or by the thermal energy diffused over heated grain surface. Therefore, the ice composition is an important tracer of physical conditions where the ices form. Ices have been studied via their absorption features against continuum sources, such as young stellar objects or evolved background stars, in infrared wavelengths. The Spitzer IRS was the most sensitive spectrometer for the observations of infrared ice absorption features. We has been developing an automated analysis tool for the Spitzer IRS spectra, especially for the 15 ㎛ CO₂ bending mode. The 15 ㎛ CO₂ absorption feature is very useful for the study of accretion process in star formation since its spectral shape varies with thermal condition of the dust grains. Eventually, this tool will cover the whole range of the Spitzer IRS spectrum (5~20 ㎛).

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.6
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• pp.57-65
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• 2010

In this paper, we present a universal steganalysis scheme. The proposed method extract features of two types. First feature set is extracted from histogram characteristic of the wavelet subbands. Second feature set is determined by statistical moments of wavelet characteristic functions. 3-level wavelet decomposition is performed for stego image and cover image using the Haar wavelet basis. We extract one features from 9 high frequency subbands of 12 subbands. The number of second features is 39. We use total 48 features for steganalysis. Multi layer perceptron(MLP) is applied as classifier to distinguish between cover images and stego images. To evaluate the proposed steganalysis method, we use the CorelDraw image database. We test the performance of our proposed steganalysis method over LSB method, spread spectrum data hiding method, blind spread spectrum data hiding method and F5 data hiding method. The proposed method outperforms the previous methods in sensitivity, specificity, error rate and area under ROC curve, etc.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.369-375
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• 2001

For Optimization technology Was Developed in 1960, the Optimization Technology have grown into a full-featured, robust, highly rated and highly used. And Optimization techniques, having reached a degree of maturity over the past several years, are being used in a wide spectrum of industries, including aerospace, automotive, chemical, electrical, and manufacturing industries. With rapidly advancing computer technology, computers are becoming more powerful, and correspondingly, the size and the complexity of the problems being solved using Optimization techniques are also increasing. But Optimization techniques with analysis solver have many problems. For instance, the difficulties that a particular interface must be coded for each design problem and that the designer should be familiar with the optimization program as well as the analysis program. The purpose of this paper is Optimal Design Framework for Mechanical systems design. This Design Framework has two Optimizers, ADS (local optimizer) and RSM(Response Surface Method), and graphic user interfaces for formulation and optimum design problem and controlling the design process. Current Design Framework tested by two analysis solver, ADAMS and ANSYS. First this paper focused on the core Framework and their conception. In the second of the paper, I cover subjects such as Design Framework Operation. Next, The validity and effectiveness of Design Framework are shown by applying it to many practical design problems and obtaining satisfactory results. Finally, if you are an advanced Operator, you might want to use Response Surface Method, so that cover the result applied by RSM. here.

• Korean Journal of Remote Sensing
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• v.31 no.2
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• pp.137-148
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• 2015

The National Institute of Meteorological Research (NIMR) has operated the Fourier Transform InfraRed (FTIR) spectrometer which is the Atmospheric Emitted Radiance Interferometer (AERI) in Anmyeon island, Korea since June 2010. The ground-based AERI with similar hyper-spectral infrared sensor to satellite could be an alternative way to validate satellite-based remote sensing. In this regard, the NIMR has focused on the improvement of retrieval quality from the AERI, particularly cloud-data filtering method. The AERI spectrum which is measured on a typical clear day is selected reference spectrum and we used region of atmospheric window. We performed test of threshold in order to select valid threshold. We retrieved methane using new method which is used reference spectrum, and the other method which is used KLAPS cloud cover information, each retrieved methane was compared with that of ground-based in-situ measurements. The quality of AERI methane retrievals of new method was significantly more improved than method of used KLAPS. In addition, the comparison of vertical total column of methane from AERI and GOSAT shows good result.

• Journal of the Korean Society of Radiology
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• v.6 no.6
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• pp.483-487
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• 2012

In 1895, the discovered X-ray is used for not only in this field of medicine wide but also field. The detection of radiation after, people realized the risk of the radiation exposured recommended the principle about the protection of radiation by the part of the effort for lowering the radiation exposure. In this recommendation, all unnecessary radiation exposure have to be prevented by All doses include the protection of radiation, general idea of applicable two kinds of that it has to low maintain. Presently, in the General X-ray room of the clinical, the lead (Pb) was used for the shielding, However, because it had the problem of the lead poisoning which is fatal in the human body, the alternatives was showed. and Among them, the material that it is the tungsten was presented. in this research, the absorbed spectrum according to the thickness in the continuous X-ray energy of the tungsten which is not harmful to the human body through the Monte Carlo simulation, tried to compare with the absorbed spectrum of the lead (Pb). The tungsten confirmed that simulation presumption than result lead in the whole domain that absorbed probability was higher and it is considered that tungsten shows the absorbed efficiency higher than the lead in particularly, 70 keV ~ 90 keV and the tungsten is more useful to the X-ray energy cover of the high energy diagnostic area.