• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.682-687
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• 2003

The variations of temperature and velocity fields in a Hele-Shaw convection cell (HSC) were investigated using a holographic interferometry and 2-D PIV system with varying Rayleigh number. To measure quasisteady changes of temperature field, two different measurement methods of holographic interferometry; double-exposure method and real-time method, were employed. In the double-exposure method, unwanted waves can be eliminated effectively using digital image processing technique and the reconstruction images are clear, but transient flow structure cannot be reconstructed clearly. On the other hand, transient convective flow can be reconstructed well using the real-time method. However, the fringe patterns reconstructed by the real-time method contain more noises, compared with the double-exposure method. Experimental results show a steady flow pattern at low Rayleigh numbers and a time-dependent periodic flow structure at high Rayleigh numbers. The periodic flow pattern at high Rayleigh numbers obtained by the real-time holographic interferometer method is in a good agreement with the PIV results.

• 한국공작기계학회논문집
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• 제17권3호
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• pp.8-13
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• 2008

The paper proposes a model-based measurement of unsteady flow rate by using distributed parameter pipeline model and the measured pressure values at two distant points along the pipeline. The distributed parameter model of hydraulic pipeline is applied with consideration of frequency dependent viscosity friction and unsteady velocity distribution at a cross section of a pipeline. By using the self-diagnostics functions of the measurement method, the validity is investigated by comparison with the measured and estimated pressure and flow rate wave forms at the halfway section on the pipeline. The results show good agreement between the estimated flow rate wave forms and theoretical those under unsteady laminar flow conditions. The method proposed here is useful in estimating unsteady flow rate through an arbitrary cross section in hydraulic pipeline and components without installing an instantaneous flowmeter.

• International Journal of Air-Conditioning and Refrigeration
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• 제8권2호
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• pp.11-22
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• 2000

Holographic interferometric tomography can provide reconstruction of instantaneous three-dimensional gross flow fields. The technique however confronts ill-posed reconstruction problems in practical applications. Experimental data are usually limited in projection and angular scanning when a field is captured instantaneously or under the obstruction of test models and test section enclosures. An algorithm, based on a series expansion method, has been developed to improve the reconstruction under the ill-posed conditions. A three-dimensional natural convection flow around two interacting isothermal cubes is experimentally investigated. The flow can provide a challenging reconstruction problem and lend itself to accurate numerical solution for comparison. The refractive index fields at two horizontal sections of the thermal plume with and without an opaque object are reconstructed at a limited view angle of 80$\circ$. The experimental reconstructions are then compared with those from numerical calculation and thermocouple thermometry. It confirms that the technique is applicable to reconstruction of reasonably complex, three-dimensional flow fields.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 센서 박막재료 반도체재료 기술교육
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• pp.1-6
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• 2002

Plasma processing of semiconductor materials plays a dominant role in microelectronic technology. During last century, plasma have gone a way from laboratory phenomena to industrial applications due to intensive progress in both scientific and industrial trends. Improvement and development of new experience together with development of plasma theory and plasma diagnostics methods. A most parameters (pressure, flow rate, power density) and various levels of plasma system (energy distribution, volume gas chemistry, transport, heterogeneous effects) to understand the whole process mechanism. It will allow us to choose a correct ways for processes optimization.

• 대한한의진단학회지
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• 제19권1호
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• pp.47-54
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• 2015

Objective Wave reflection is an important factor that determines the shape of the pulse wave. The purpose of this study is to compare the conventional method used for estimating the reflection site of pulse with a cardiovascular simulator. Methods: In this study, cardiovascular simulator with one elastic tube was used. The pressure and flow was measured simultaneously at three different points. The measured data were used to the conventional methods to estimate the pulse wave reflection site. The results were compared with the known length which were the distances from the measured points to the end of tube. Results & Conclusions: There is a significant error with the time domain method. While, the reflection site with the frequency domain method was similar to the actual reflection site.

• 대한한의진단학회지
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• 제14권1호
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• pp.79-95
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• 2010

Background and Purpose : By preventing diseases caused by exogenous evil, disorder of internal organs, and seven modes of emotions and adapting to mother nature when the mind is unsettled, and keeping the body and mind relaxed diseases can be avoided, but there can be unpredicted situations caused accidentally by stroke. Currently the general prescription is regulating the flow of vital energy including drugs eliminating blood stasis. Even though the stroke is resulted from diseases caused by exogenous evil, by observing the patient's physical appearance, essence of life, vital energy, and mental faculties which are believed to be the functions of the heart to clear the upper body and invigorate the functions of the spleen and stomach and purge with drugs of warm nature is a closer approach than simply prescribing vital energy regulating drugs with eliminating blood stasis to the main purpose of treatment. Methods : 1) The subject of the study are 2 cases of patients who have visited the private hospital of the person who is announcing the results of the study. These patients have been given a diagnosis of edema or cystoma caused by bursitis in the knee joint through perception or medical examination and were waiting for operational application. 2) Sources related to stroke from Dong Eui Bo Gwam(東醫寶鑑) were used as the general standard of Korean Traditional Medicine, and to promote the understanding the original text and the translation has been given. 3) By observing the whole body such as the patient's usual physical appearance, essence of life, vital energy, and mental faculties which are believed to be the functions of the heart, or partly using the "Yin is even and well while Yang is firm" theory of "Plain Questions" as the background to present the results of the clinical study. Results and Conclusion : Generally the prescriptions from the first volume of Dong Eui Bo Gwam(東醫寶鑑) are mostly drugs eliminating stagnated blood including extravasated blood and the blood moving sluggishly in circulation or congested in a viscus, alleviating pain, invigorating blood circulation. Also prescriptions for bone fracture or fracture of bones and sinews are mostly to eradicate blood stasis with drastic drugs or coaptation drugs added to drugs eliminating stagnated blood including extravasated blood and the blood moving sluggishly in circulation or congested in a viscus, alleviating pain, invigorating vital energy, possessing warm properties for the Xue system.

• 한국안전학회지
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• 제12권3호
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• pp.97-105
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• 1997

Mo-99(Molybdenum) is the only source of Tc-99m(Technetium) which is most frequently used in nuclear medical diagnostics and the demand is on the increase recently. Separation and refining of Mo-99 was investigated by adsorption and desorption on alumina. At pH=0.63, adsorption isotherm of Mo was fitted by Redlich ＆ Peterson equation using the adsorption experimental data. It was found that the pore diffusion model ($D_p=1.4{\times}10^{-6}cm^2/s, K_f/=0.4 cm/s$) agreed well with batch adsorption experimental data. RTDs(Residence Time Distributions ) were measured and axial dispersion coefficients were obtained in the fixed bed absorber according to the changes of the flow rate using 0.05% -NaCl. From the adsorption experimental data, it was shown that the behavior of breakthroughs depended on flow rate. Mo recovery yield was increased as adsorption flow rate was increased and desorption flow rate was decreased.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2007년도 동계학술발표대회 논문집
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• pp.576-584
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• 2007

A PIV(Particle Imaging Velocimetry) diagnostic technique for the evaluation of the flow characteristics in refrigerator is introduced. Smoke particles of which density is small enough to follow up the air flow are used for visualization of the air flows in the refrigerators. A rectangular room model is tested for the verifications of the dignostic technique. By evaluating the turbulent intensity and the deviation value of the turbulent intensity distribution that were obtained from PIV results, an optimal ventilating condition is suggested. The constructed technique is used for the diagnostics on the flow of an actual refrigerator. It has experimentally proved that the present technique is able to evaluate the ventilation conditions of refrigerators.

• International Journal of Oral Biology
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• 제44권1호
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• pp.8-13
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• 2019

Recently, the importance of on-site detection of pathogens has drawn attention in the field of molecular diagnostics. Unlike in a laboratory environment, on-site detection of pathogens is performed under limited resources. In this study, we tried to optimize the experimental conditions for on-site detection of pathogens using a combination of ultra-fast convection polymerase chain reaction (cPCR), which does not require regular electricity, and nucleic acid lateral flow (NALF) immunoassay. Salmonella species was used as the model pathogen. DNA was amplified within 21 minutes (equivalent to 30 cycles of polymerase chain reaction) using ultra-fast cPCR, and the amplified DNA was detected within approximately 5 minutes using NALF immunoassay with nucleic acid detection (NAD) cassettes. In order to avoid false-positive results with NAD cassettes, we reduced the primer concentration or ultra-fast cPCR run time. For singleplex ultra-fast cPCR, the primer concentration needed to be lowered to $3{\mu}M$ or the run time needed to be reduced to 14 minutes. For duplex ultra-fast cPCR, $2{\mu}M$ of each primer set needed to be used or the run time needed to be reduced to 14 minutes. Under the conditions optimized in this study, the combination of ultra-fast cPCR and NALF immunoassay can be applied to on-site detection of pathogens. The combination can be easily applied to the detection of oral pathogens.

• 설비공학논문집
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• 제11권6호
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• pp.749-757
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• 1999

Holographic interferornetric tomography can provide reconstruction of instantaneous three dimensional gross flow fields. The technique however confronts ill-posed reconstruction problems in practical applications. Experimental data are usually limited in projection and angular scanning when a field is captured instantaneously or under the obstruction of test models and test section enclosures. An algorithm, based on a series expansion method, has been developed to improve the reconstruction under the ill-posed conditions. A three-dimensional natural convection flow around two interacting isothermal cubes is experimentally investigated. The flow can provide a challenging reconstruction problem and lend itself to accurate numerical solution for comparison. The refractive index fields at two horizontal sections of the thermal plume with and without an opaque object are reconstructed at a limited view angle of 80" The experimental reconstructions are then compared with those from numerical calculation and thermocouple thermometry. It confirms that the technique is applicable to reconstruction of reasonably complex, three-dimensional flow fields.elds.