• Journal of the Korean Electrochemical Society
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• v.8 no.1
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• pp.32-36
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• 2005

[ $WO_3$ ] and $NiO-WO_3$ thin films were deposited on a Si (100) substrate by using high vacuum thermal evaporation. The effects of various film thicknesses on the surface morphology $WO_3$ and $NiO-WO_3$ thin films were investigated. X-ray diffraction (XRD), Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy(XPS) were employed to characterize the deposited films. The results suggest that as $WO_3$ thin films became thick, their grain grew up to a $0.6{\mu}m$. On the other hand, NiO-doping to $WO_3$ thin films inhibited the grain growth five times less than undoped $WO_3$ thin films. This results show that NiO doping inhibited the grain growing of $WO_3$ thin films. Also, the variation of NOx sensitivity $(R_{NOx}/R_{air})$ to the thickness of $WO_3$ and $NiO-WO_3$ thin films were measured according to the thickness change of thin films and the working temperature of sensor in 5ppm NOx gas. As a result, $NiO-WO_3$ thin films showed more excellent properties than $WO_3$ thin films for NOx sensitivity.

• Journal of Energy Engineering
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• v.29 no.2
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• pp.61-67
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• 2020

ESS-based buildings are being widely studied as an effective methods for saving energy with ZEB, BEMS, and FEMS. However, in large scale buildings, there are many energy-consuming facilities, so it is necessary to identify important energy-consuming facilities to build a real-time measurement system. In addition, there are a myriad of factors that affect the dependent variable of energy use, therefore there is a limitation that effective energy management is difficult. Therefore, this study applied the measurement boundary setting methodology according to the energy supply status through due diligence for the demonstration ESS distribution logistics facility, and suggested the methodolgy for presenting priority for the construction of the measurement system. Afterwards, the impact variables that Acting as an independent variable affecting the energy consumption of the distribution and logistics facilities were categorized into intrinsic and meteorological variables. Lastly, all factors that could affect the energy consumption of the actual distribution and logistics facilities, were classified and presented as guidelines list. By applying the results of this study, it is possible to build a monitoring system at a low cost and high efficiency in a distribution and logistics facility with a complex structure. And by identifying the main independent variables for the measured energy consumption, effectively identifying trends in energy consumption and deriving saving points It is expected to be able to operate the ESS-based infrastructure.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.3
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• pp.382-388
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• 2002

In the present study, crown diameters and their sexual differences in deciduous teeth were investigated in children of Chon-ju city, Korea. Plaster casts of the deciduous dentitions obtained from 50 boys and 50 girls were examined. Mesiodistal and buccolingual crown diameters were measured using a digital caliper(0.01mm) according to the definitions of Seipel and Moorees et al. These measurements were performed three times, and intra-observer measurement errors were calculated by the single determination method. The crown index, module and area were calculated in order to provide a comparison of crown proportions. The results obtained were summarized as follows; 1. The mean values of intra-observer measurement errors were 0.255mm and are unlikely to have influenced the statistical analysis. 2. The mean values of mesiodistal and buccolingual crown diameters examined were larger in boys than girls. 3. The mean coefficient of variation was 5.6 in the deciduous dentition. There were a trend for the primary second molar to be the least variable in size of all teeth both in boys and girls. 4. Fluctuating asymmetry is the difference between left and right antimeres in individuals. Primary second molars were less asymmetrical than primary first molars in both dimensions. 5. In maxillary teeth, Crown index is larger in boys than in girls. In contrast, in mandibular teeth, except primary canine, it is larger in girls than in boys. Crown module is larger in boys than in girls and increased progressively from primary first incisor to primary second molar. Crown area is consistently larger in boys than in girls. The minimum crown area is mandibular primary incisor and maximum crown area is maxillary primary second molar.

• Tuberculosis and Respiratory Diseases
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• v.52 no.1
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• pp.76-85
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• 2002

A primary pulmonary malignant lymphoma is a rare disease. It is thought to be a category of non-Hodgkin's lymphoma arising from the bronchous-associated lymphoid tissue (BALT). The majority of primary pulmonary lymphomas are low-grade, small B-cell lymphomas, which are associated with Sjogren's syndrome and similar autoimmune disorders. A case of primary pulmonary low-grade B-cell lymphoma arising from the BALT was encountered in a patient with systemic lupus erythematosus. A 54-year-old man was admitted to the hospital for the evaluation of left pleuritic chest pain and multiple joint pain in both hands. Serologic tests for collagen vascular disease were performed. The results of ANA and anti-ds-DNA were all positive. The computed tomography of the chest showed patchy consolidations in the left lower lobe with a pleural effusion and a video-assisted thoracoscopic biopsy was performed. Here we report a case of a low-grade B-cell lymphoma of BALT in a patient with systemic lupus erythematosus with a review of the relevant literatures.

• Journal of the Korean Electrochemical Society
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• v.14 no.1
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• pp.1-8
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• 2011

Ionic liquids are room-temperature molten salts, composed of organic mostly of organic ions that may undergo almost unlimited structural variation. We approach the new aspects of ionic liquids in applications where the semiconductor nanoparticles used as sensitizers of solar cells. We studied the effects of ionic liquids as capping ligand and/or solvent, on the morphology and phase of the CdSe/ZnS nanoparticles. Colloidal CdSe/ZnS nanoparticles were synthesized using a series of imidazolium ionic liquids; 1-R-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([RMIM][TFSI]), where R = ethyl ([EMIM]), butyl ([BMIM]), hexyl ([HMIM]), octyl ([OMIM]). The average size of nanoparticles was 8~9 nm, and both zinc-blende and wurtzite phase was produced. We also synthesized the nanoparticles using a mixture of trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)imide ([$P_{6,6,6,14}$][TFSI]) and octadecene (ODE). The CdSe/ZnS nanoparticles have a smaller size (5.5 nm) than that synthesized using imidazolium, and with a controlled phase from zinc-blende to wurtzite by increasing the volume ratio of [$P_{6,6,6,14}$][TFSI]. For the first time, the phase and size control of the CdSe/ZnS nanoparticles was successfully demonstrated using those ionic liquids.

• Proceedings of the Korean Society of Rheology Conference
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• 2006.06a
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• pp.81-84
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• 2006

Slot coating process, in continuous and patch modes, has been applied for the many precise coating products, e.g., flat panel displays and second batteries. However, manufacturing uniform coating products is not a trivial task at high-speed operations because various flow instabilities or defects such as leaking, bubbles, ribbing, and rivulets are frequently observed in this process. It is no wonder, therefore, that many efforts to understand the various aspects of dynamics and coating windows of this process have been made both in academia and industry. In this study, as the first topic, flow dynamics within the coating bead in slot coating process has been investigated using the one-dimensional viscocapillary model by lubrication approximation and two-dimensional model by Flow-3D software. Especially, operability windows in both 1D and 2D cases with various slot die lip designs have been successfully portrayed. Also, effects of process conditions like viscosity and coating gap size on slot coating window have been analyzed. Also, some experiments to find minimum coating thickness and coating windows have been conducted using slot die coater implemented with flow visualization device, corroborating the numerical results. As the second topic, flow dynamics of both Newtonian and Non-Newtonian fluids in patch or pattern slot coating process, which is employed in manufacturing IT products such as secondary batteries, has been investigated for the purpose of optimal process designs. As a matter of fact, the flow control in this system is more difficult than in continuous case because od its transient or time-dependent nature. The internal die and die lip designs for patterned uniform coating products have been obtained by controlling flow behaviors of coating liquids issuing from slot. Numerical simulations have been performed using Fluent and Flow-3D packages. Flow behavior and pressure distribution inside the slot die has been compared with various die internal shapes and geometries. In the coating bead region, efforts to reduce irregular coating defects in head and tail parts of one patterned coating unit have been tried by changing die lip shapes. It has been concluded that optimal die internal design gas been developed, guaranteeing uniform velocity distribution of both Newtonian and shear thinning fluids at the die exit. And also optimal die lip design has been established, providing the longer uniform coating layer thickness within one coating unit.

• Journal of Chest Surgery
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• v.29 no.11
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• pp.1212-1217
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• 1996

From Dec. 1993 to May 1995, 9 male and 5 female patients ranging in age from 25 to 65 years, were operated on for ascending aorta and/or aortic arch diseases. Six patients had acute aortic dissection, type A(ruptured in 4 cases); four had ruptured ascending aortic aneurysm; three had annuloaortic ectasia(ruptured in 1 cases); one had aortic arch aneurysm. The diagnostic procedures were echo cardiography and dynamic CT scan in all patients having acute dissection or rupture. The aortic angiography was performed in two cases. Indications for operations were rupture in five cases, acute aortic dissection in five cases, severe congestive heart failure in two cases, progressive aortic insufficiency in one case and impending rupture in one case. The emergent repair was performed in ten cases(71%). The surgical treatment consisted of 6 Cabrol operations, a Cabrol operation combined with arch replacement, a modified Bentall operation, 4 replacement of ascending aorta, a replacement of aortic arch, and a replacement of ascending aorta and aortic arch. Complications were a hypoxic encephalopathy, two atrial fibrillations, a sternal deheiscence, and a mediastinitis. Two early mortality(14%) were due to intractable bleeding and multiple organ failure, and one late mortality(7%) was due to ventricular arrhythmia. In eleven survivors, follow-up period was from 2 months to 12 months and the course was uneventful.

• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.2
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• pp.176-183
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• 2014

Acoustic emission testing (AET) of cylinders is advantageous in that it can be directly conducted on cylinders installed in a car, without needing to dissemble them on a real-time basis. Therefore, users prefer AET over other nondestructive testing methods. Owing to these advantages of AET, it has been approved by the Department of Transportation of the U.S. as a safety evaluation method for pressure containers or as an alternative to the hydroproof testing method. This paper presents a study of the quantitative evaluation criteria for a container having ultrasonic testing defects and also for Type 1 and Type 2 gas cylinders, which are defective seamless pressure containers provided by NK, a manufacturer of pressure containers. For the Type 1 cylinder, the process from crack growth to leak was observed in a repetitive fatigue test using a 113 L container according to ASTM E 1419-02. Further, for the Type 2 cylinder, integrity was evaluated using a 119 L sound container and a container damaged by hydraulic pressure, by the slow-fill method according to ASTM E 2191-02. Based on the AET results of the Type 1 and Type 2 cylinders, quantitative evaluation criteria were established for a defective and non-defective container.

• Journal of Korea Multimedia Society
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• v.6 no.2
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• pp.340-351
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• 2003

We introduce our experiences of the design and implementation of the Page Together system that has expanded hyperlink metaphor to utilize human resources in the web. This system supports that a user connects with others in the web, communicates through video/audio channel, navigates same web pages simultaneously and cooperates some work on Internet. For these functions, it comprises Collaborative Browsing Module (CBM), Multimedia Conferencing Module(MCM) Data Conferencing Module(I)CM) and Multi Protocol Interface(MPI). We adopted three standard protocols, IEC, H.323 and T.120 for each nodule and it allows developers to use them easily. We also defined MPI to synchronize information of session among modules. Each module exchanges information each other in session creating process and session terminating process. After a session is created once, each module works independently as its won protocol. Interferences among modules are reduced as minimizing to exchange information. We also introduce a web site that provides web board service based on the Page Together system. A user may post a notice with a link to himself/herself on our web board. After then, if someone read that notice and has any question about it, he or she can try to connect to the writer as clicking the link in that notice and communicate each other. This service site shows that our system can be applied to diverse internet services such as distance teaming and distance conference.

• Korean Journal of Dental Materials
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• v.44 no.4
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• pp.329-336
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• 2017

This study evaluates the machining accuracy of the custom abutment design according to the selected convergence angle and radius of curvature value in the CAD program. Ten custom abutments were designed based on dental CAD. And then, the fabricated custom abutment was scanned ten times using a contact scanner. The data of the scanned custom abutment was saved as "Test STL" file. The Geomagic studio software was used to superposition each exported as an "Test STL" file with the CAD-reference-model STL file (CRM) specified by the same name. In the experimental results, the A8 group (convergence angle $8^{\circ}$) showed lower error than the A4 group (convergence angle $4^{\circ}$) . In addition, the higher the radius of curvature, the less error in the top and chamfer regions of the custom abutment (p< 0.05). Overall, the convergence angle and radius of curvature value in the custom abutment design were found to affect the machining accuracy.