• Progress in Superconductivity and Cryogenics
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• v.23 no.4
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• pp.56-60
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• 2021

The microwave Radar used for special purposes in the past is being applied in various areas due to the technological advancement and cost reduction, and is particularly applied to autonomous driving in the automobile field. The FMCW (Frequency Modulated Continuous Wave) Radar can acquire level information of liquid in vessel based on the beat frequency obtained by continuously transmitting and receiving signals by modulating the frequency over time. However, for cryogenic fluids with small impedance differences between liquid medium and gas medium, such as liquid nitrogen and liquid hydrogen, it is difficult to apply a typical Radar-based level meter. In this study, we develop an 80 GHz FMCW Radar for level measurement of cryogenic fluids with small impedance differences between media and analyze its characteristics. Here, because of the low intrinsic impedance difference, most of the transmitted signal passes through the liquid nitrogen interface and is reflected at the bottom of the vessel. To solve this problem, a radar measurement algorithm was designed to detect multiple targets and separate the distance signal to the bottom of the vessel in order to estimate the precise position on the liquid nitrogen interface. Thereafter, performance verification experiments were performed according to the liquid nitrogen level using the developed radar level meter.

• Textile Coloration and Finishing
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• v.15 no.2
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• pp.93-101
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• 2003

To acquire dyeing ability on aramid(Nomex) spun yarn in supercritical fluid dyeing, supercritical fluid dying(SFD) machine of 3L scale was designed. C. I. Disperse Red 60 and Red 360 were used in this work. It was possible to increase dyeing ability and to get level dyeing of fiber by attaching assistance devices(controlling device of supercritical fluid, nozzle, cover of carrier, etc.) to SFD machine. Physical properties(tensile strength, elongation, shrinkage) of Nomex spun yam treated by SFD were not changed. K/S values of dyed Nomex spun yam with Red 360 were higher than that with Red 60 and color fastness of dyed Nomex spun yam by SFD was similar to that by conventional dyeing method.

• Journal of the Korean Ceramic Society
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• v.35 no.10
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• pp.1049-1054
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• 1998

In order to fabricate ideal powders new processing is necessary in which the solute atoms in solution ra-pidly move to mix each other to the degree of molecular level the viscosity of solution should be low not to effect the moving of solute atoms and the powders could be directly obtained as crystalline. Supercritical fluid is defined as condensed gas sated up to its critical pressure and temperature. In this paper su-percritical fluid methods were studied as a new ceramic processing of powder preparation. The crystalline powders of TiO2 which are useful for electronic ceramic materials were fabricated by hydrolysis of titanium (IV) ethoxide using ethanol as a supercritical fluid at the condition of 270$\pm$3$^{\circ}C$, 7.3 MPa for 2hr. The cry stalline anatase powders could be directly obtained and its primary particle size was 20 min.

• Journal of Veterinary Clinics
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• v.34 no.2
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• pp.98-102
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• 2017

A 7-year-old, intact, female Siberian husky presented with vomiting and diarrhea after a fight with a dog with which it lived. The bitch was diagnosed with pyometra and severe dehydration. The patient received IV fluid therapy for 2 day pre- and post-operatively. Four days post-surgery, the patient had a decreased level of consciousness and suffered a tonic-clonic generalized seizure. On magnetic resonance imaging and histopathological findings, a diagnosis of laminar cortical necrosis caused by fluid overload was made. This case provides important information on the potential for fluid overload in a dehydrated patient giving rise to critical condition and death.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.1027-1030
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• 2013

Background: Peritoneal washing cytology (PWC) that shows the microscopic intra-peritoneal spread of gynaecologic cancers is not used in staging but is known as prognostic factor and effective in planning the intensity of the therapy. False negative or false positive results clearly affect the ability to make the best decision for therapy. In this study we assessed levels of tumour markers, carcinoembryonic antigen (CEA), cancer antigen 125 (CA-125) and carbohydrate antigen (CA19-9), in peritoneal washing fluid to establish any possible contribution to the peritoneal washing cytology in patients operated for gynaecologic cancer. Materials and Methods: Preoperative tumour markers were studied in serum of blood samples obtained from the patients for preoperative evaluation of a gynaecologic operation. In the same group peritoneal tumour markers were studied in the washing fluid obtained for intraoperative cytological evaluation. Results: This study included a total of 94 patients, 62 with malignant and 32 with benign histopathology. The sensitivity of the cytological examination was found to be 21% with a specificity of 100%. When evaluated with CEA the sensitivity of the cytological examination has increased to 37%. Conclusions: In addition to examination of PWC, the level of CEA, a tumour marker, in peritoneal washing fluid can make a diagnostic contribution. Determining the level of CEA in peritoneal washing fluid will be useful in the management of gynaecologic cancers.

• The Journal of Korean Medicine
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• v.23 no.2
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• pp.88-96
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• 2002

Objective : This study attempted to evaluate the ultrasonographic diagnosis of sinusitis compared to X-ray diagnosis and further to help the diagnosis and treatment of sinusitis through oriental medicine. Methods : Both A-mode ultrasonography and X-ray were taken of 30 symptom-positive patients and 10 symptom-negative controls. Nasal obstruction, rhinorrhea, postnasal drip, headache (facial pain), hyposmia (anosmia), throat discomfort and chronic cough were included in the symptoms of sinusitis. Both ultrasonographic and X-ray findings were divided into four groups (clear, mucosal thickening, air-fluid level and cystic shape) according to severity. Results : 1. The symptoms of patients (n=30) were as follows: nasal obstruction (83.3%), rhinorrhea (70.0%), postnasal drip (60.0%), chronic cough (53.3%), headache (40.0%), throat discomfort (40.0%), hyposmia (26.7%). 2. There was a significant correlation between symptoms and ultrasonographic findings (n=40, ${\gamma}=0.550$, P=0.001). 3. There was a significant correlation between symptoms and X-ray findings (n=40, ${\gamma}=0.555$, P=0.001). 4. There was a significant whole coincidence between ultrasonographic and X-ray findings (n=60, ${\gamma}=0.335, P=0.00l). Moreover, there was a significant coincidental trend between the two findings as they became severe (n=60, ${\gamma}=6.284$, P=0.012). 5. The distance of the ultrasonographic echoes was as follows: clear echo (n=9, from transducer pulse to air mucosa echo) $0.90{\pm}0.19cm$, mucosal thickening echo (n=23, from transducer pulse to air mucosa echo) 1.85{\pm}0.14cm, air-fluid level echo (n=26, from transducer pulse to back wall echo) $3.70{\pm}0.16cm$. 6. The highest diagnostic reliability of the ultrasonographic findings compared to X-ray findings was as follows: over-diagnosis in clear finding 77.3%, matched diagnosis in mucosal thickening finding 62.0%, matched diagnosis in air-fluid level finding 86.7%, matched diagnosis and under-diagnosis in cystic shape finding 50.0%. 7. In mucosal thickening, air-fluid level and cystic shape finding, there was a significant individual coincidence between the ultrasonographic and X-ray findings. In clear finding, there was no significant individual coincidence between the two findings. Conclusion : The ultrasonographic diagnosis significantly reflects the symptoms of sinusitis like X-ray diagnosis and is a valuable tool to screen prognostic factors such as mucosal thickening, air-fluid level and cyst. Therefore the ultrasonography will be useful for the diagnosis and treatment of sinusitis in oriental medicine.

• Analytical Science and Technology
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• v.20 no.4
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• pp.268-278
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• 2007

Nitrite which can be derived from water for dilution of metal working fluid can induce nitroso compounds which can be classified as carcinogen, if it co-exists with ethanolamines added for pH control in metal working fluid. The survey of nitrite, nitrate and nitroso-compounds level in 42 metal-working fluids collected from 17 factories was done by ion chromatography and gas chromatography with mass detector. Diluted metal working fluid showed higher level of nitrite and nitrate compared with raw fluid. Nitrite was detected in 11 (52%) samples among 21 diluted solution. Three (14%) samples showed over German recommendation level ($20{\mu}g/mL$).N-nitrosodiethanolamine(NDELA) was detected in 18 samples among 21 diluted solution. Seven (33%) samples showed over German recommendation level ($5{\mu}g/mL$). The concentration of NDELA was correlated with nitrite ion ($R^2=0.453$, n=19).

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.04a
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• pp.609-614
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• 2014

This study is on the experiment of the pipe noise due to the internal fluid. The straight pipe, the $90^{\circ}$ mitred pipe, rounded $90^{\circ}$ and $1350^{\circ}$ pipe were tested and measured the vibration and noise. In the experiment, the vibration and noise level of the straight pipe and rounded pipes show that the vibration and noise level are almost same. The $90^{\circ}$ mitred pipe shows the high vibration and noise level. In the prediction of noise due to the internal flow, the use of pipe surface vibration and radiation efficiency shows good agreement with experiment result.

• The KSFM Journal of Fluid Machinery
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• v.13 no.3
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• pp.24-29
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• 2010

Axial fans for an air-conditioning unit are designed to equip the system with an expected flow-rate and low noise level by applying the blade design method of multi-sectioning and local camber generation. In this study, the distributions of chord length, stagger angle, and camber angle are globally and locally determined for the given specific speed, which is considered to be relatively high. The mock-up fans are observed to satisfy the aerodynamic performance and the noise level for the system simultaneously and discussed in terms of local flow patterns related to the emitted noise.

• 한국전산유체공학회:학술대회논문집
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• 2008.03a
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• pp.221-226
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• 2008

Numerical simulation is performed for microdroplet deposition on a pre-patterned micro-structure. The level-set method for tracking the liquid-gas interface is extended to treat the immersed (or irregular-shaped) solid surface. The no-slip condition at the fluid-solid interface as well as the matching conditions at the liquid-gas interface is accurately imposed by incorporating the ghost fluid approach based on a sharp-interface representation. The method is further extended to treat the contact angle condition at an immersed solid surface. The present computation of a patterning process using microdroplet ejection demonstrates that the multiphase characteristics between the liquid-gas-solid phases can be used to improve the patterning accuracy.