• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.367-372
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• 2022

The effect of the addition of a polyvinylchloride (PVC) non-solvent to a PVC-tetrahydrofuran (THF) solution on the surface properties of the PVC thin film was analyzed. The non-solvents used were composed of alcohol-based and non-alcoholic ones. Surface morphologies of PVC thin films according to the addition of the non-solvent were compared. In addition, the hydrophobic properties relying on the surface characteristics were compared. The micro-bubbles generated in the preparation of PVC-THF solution affected the surface morphology of the thin film. In order to implement the normal surface physical properties of the coating thin film at the relatively high concentration of PVC-THF solution, the selection of appropriate drying method was required. When an alcohol-based non-solvent was added, a PVC thin film having a granular porous surface was obtained and exhibited super hydrophobic properties. The volume ratio of the PVC-THF solution to the non-solvent affects the surface shape of the coating thin film. The larger the amount of non-solvent was added, the more advantageous it was to form a super hydrophobic PVC thin film.

• Nuclear Engineering and Technology
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• v.54 no.4
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• pp.1421-1430
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• 2022

The computation of the solid angle and the detector efficiency is considering to be one of the most important factors during the measuring process for the radioactivity, especially the cylindrical γ-ray NaI(Tl) detectors nowadays have applications in several fields such as industry, hazardous for health, the gamma-ray radiation detectors grow to be the main essential instruments in radiation protection sector. In the present work, a generic numerical simulation method (NSM) for calculating the efficiency of the γ-ray spectrometry setup is established. The formulas are suitable for any type of source-to-detector shape and can be valuable to determine the full-energy peak and the total efficiencies and P/T ratio of cylindrical γ-ray NaI(Tl) detector setup concerning the truncated conical radioactive source. This methodology is based on estimate the path length of γ-ray radiation inside the detector active medium, inside the source itself, and the self-attenuation correction factors, which typically use to correct the sample attenuation of the original geometry source. The calculations can be completed in general by using extra reasonable and complicate analytical and numerical techniques than the standard models; especially the effective solid angle, and the detector efficiency have to be calculated in case of the truncated conical radioactive source studied condition. Moreover, the (NSM) can be used for the straight calculations of the γ-ray detector efficiency after the computation of improvement that need in the case of γ-γ coincidence summing (CS). The (NSM) confirmation of the development created by the efficiency transfer method has been achieved by comparing the results of the measuring truncated conical radioactive source with certified nuclide activities with the γ-ray NaI(Tl) detector, and a good agreement was obtained after corrections of (CS). The methodology can be unlimited to find the theoretical efficiencies and modifications equivalent to any geometry by essential sufficiently the physical selective considered situation.

• Journal of the Korean Burn Society
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• v.24 no.2
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• pp.34-37
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• 2021

A 46-year-old female presented a mass on her right lower leg where she had a burn injury due to moxibustion 10 years ago. Physical examination revealed a 3 cm sized firm nodule with tenderness. Plain radiograph was performed and it revealed well-defined calcifications. According to the history of moxibustion burn injury and the result of plain radiograph, dystrophic calcinosis cutis caused by burn injury was suspected. The patient underwent excisional biopsy using pre-,intra-, and post-operative ultrasonography (USG). There was no sign of recurrence. Herein, we report a case of a 46-year-old healthy woman who presented with single hard nodule on the right lower leg. Our case is worthwhile in two respects. First, It is first case report of dystrophic calcinosis cutis due to moxibustion burn injury. In east asian culture, moxibustion is a commonly conducted procedure and it often induces burn injury. Second, USG was used pre-, intra-, and post-operatively to assess the shape, location, and depth of the calcinosis cutis and to determine the surgical margin.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.28 no.1
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• pp.23-30
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• 2022

This study investigated the characteristics for rice husk pulverization and surface modification of biomass byproducts composed of rice husk, corn extract gourd, wheat bran, and soybean curd. The size of particles of rice husk was at 6.44 ㎛ and represented the most affordable material for preparing the bio-degradable film among the tested byproducts. The silane treatment and adding 2% of ESO (Epoxidized soybean oil) and 3-aminopropyl triethoxysilane solution mixed in a 1:1 ratio were best to the surface modification and SEM-based particle shape. Above the results, adding 2% of mixed solution after silane treatment of rice husks processed through an air classifying mill (ACM) allows for its use as a raw material of bio-degradable plastic film.

• Journal of the Korean Applied Science and Technology
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• v.40 no.1
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• pp.146-159
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• 2023

As a makeup technique for a baby-faced image, there will be a difference in perception of the expression technique of baby-faced makeup according to general matters.' Two hypotheses were supported: 'There will be a difference in perception of the expression technique of baby face makeup depending on the general characteristics', and the makeup technique for creating a baby face image is an important function for both men and women, as well as appearance. As a 'physical resource' for social activities, it was confirmed that there is an improvement in the efficiency of the body and mind and an outstanding improvement in mental ability in daily life. Through the results of the study on 'expression of baby face image makeup', awareness and interest in baby face images are high, but research on the production of baby face images is needed. The need for facial expression elements for baby face makeup is expected to be used as basic data for developing baby face images, and this study focuses on external face management for baby face images and baby face makeup.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.5
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• pp.84-94
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• 1996

In order to prevent shell sticking by providing sufficient lubrication between the strand and the mold, the mold oscillation has been used. Now it is well known that the shape of the oscillation curve has a decisive effect on the surface quality of the cast product. Besides, oscillation parameters such as stroke and frequency are also very important. In order to guarantee that parameters which have been found to be optimal for a certain grade of steel do not change with time, periodical checks of the physical condition of the whole equipment are necessary. The portable mold oscillation analyzer with integrated computer, developed by POSCO, records the movement of the mold in every spatial direction. The system uses the gap sensors to measure the mold movement (displacement ) in the two horizontal directions according to the mold narrow and broad faces and the vertical strokes in the four corners of mold. The gap sensor is a non-contacting minute displacement measuring device using the principle of high frequency eddy current loss. The mold oscillation diagnosis system integrates the gap sensors, their converters and the industrial portable computer with plug-in data acquisition boards. The all programs, such as the fast Fourier transformation module (amplitude and phase spectrums) and harmonic analysis module, was coded by LabVIEW$^{TM}$ software as the graphical language. In an own 'expert module' which is included in the diagnosis program, one can obtain much information about the mold oscillation equipment.

• The Korean Fashion and Textile Research Journal
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• v.25 no.2
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• pp.185-198
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• 2023

The purpose of this study is to obtain information necessary for the development of patient clothes that can reduce physical fatigue of caregivers by quantitatively measuring the muscle load and fatigue. The patient clothes used in this study can be broken down into three types: A type (back center zipper open suit), B type (top-to bottom separated patient clothes), and C type (front zipper open suit). The EMG measurement sites are as follows: hand muscle (brachioradialis), upper arm (biceps, triceps), shoulder (anterior deltoid, medial deltoid, posterior deltoid, upper trapezius), and waist (erector spinae); additionally, the EMG signals were measured. Through this experiment, muscle load, muscle energy consumption, and muscle fatigue generation tendency were analyzed. The results of the study revealed that the C type patient clothes required the most strength in the muscles of the shoulders, upper arms, hands, and back when being put on and taken off compared to other patient clothes. The A type clothes required a relatively large force in opening the zipper. In terms of muscle energy consumption, B type generally called for more strength when it came to the zip-up and putarmsup motions. With regard to the cover the body and put legs/hips up motions, C type used the highest amount of muscle energy, whereas A type used relatively little energy. In terms of the occurrence of muscle fatigue during the putting on and taking off of the patient's clothing, there was a difference in the area and degree of muscle fatigue in the A, B, and C types, and there was also a tendency for muscle fatigue to occur when performing repetitive movements.

• Journal of Powder Materials
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• v.30 no.2
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• pp.107-115
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• 2023

Li_1.3Al_0.3Ti_1.7(PO₄)₃(LATP) is considered a promising material for all-solid-state lithium batteries owing to its high moisture stability, wide potential window (~6 V), and relatively high ion conductivity (10^-3-10^-4 S/cm). Solid electrolytes based on LATP are manufactured via sintering, using LATP powder as the starting material. The properties of the starting materials depend on the synthesis conditions, which affect the microstructure and ionic conductivity of the solid electrolytes. In this study, we synthesize the LATP powder using sol-gel and co-precipitation methods and characterize the physical properties of powder, such as size, shape, and crystallinity. In addition, we have prepared a disc-shaped LATP solid electrolyte using LATP powder as the starting material. In addition, X-ray diffraction, scanning electron microscopy, and electrochemical impedance spectroscopic measurements are conducted to analyze the grain size, microstructures, and ion conduction properties. These results indicate that the synthesis conditions of the powder are a crucial factor in creating microstructures and affecting the conduction properties of lithium ions in solid electrolytes.

• Advances in concrete construction
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• v.15 no.3
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• pp.203-213
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• 2023

New techniques, technologies, and materials should be used to design and build sports stadiums. Since this century, much progress has been made in covering the roofs of sports stadiums, and the possibility of accurate computer calculation has been provided for stadiums, so by choosing a new structure, we can double the beauty and resistance of these stadiums. A stadium has an excellent and valuable design when its structure, shell, building, materials, and joinery follow a high architectural idea at all levels and scales. This article examines the mechanical performance of polymer cement strength in the construction of football stadiums, along with their structural knowledge in the form of the best examples in the world. Portland cement is one of the most used materials for constructing football stadiums. However, its production requires spending a lot of money, wasting energy, and damaging the environment. Considering the disadvantages in the production and consumption of concrete in different environments, it is necessary to find alternative materials. It should be used with cheaper, simpler technology, abundant primary resources, energy saving, less environmental damage, and better chemical and physical properties in concrete. High-strength concrete technology is considered a new development in the construction industry of concrete structures. In hardened concrete, strength and durability are two main factors, and as the compressive strength of concrete increases, concrete becomes more brittle. As a result, its tensile strength does not increase in proportion to the increase in compressive strength and has less strain tolerance. For this reason, the need to use is evident from the fibers in high-strength concrete. Fibers are used in concrete to increase tensile strength, prevent crack propagation, and significantly increase softness. The increase with the change of these resistances depends on the strength of concrete without fibers, the shape of fibers, and the percentage of fibers. This cement is obtained from the wastes of chemical and petrochemical industries and the wastes from coal combustion, which have the properties mentioned as substitutes for Portland cement.

• The Korean Journal of Pain
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• v.36 no.2
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• pp.208-215
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• 2023

Background: To evaluate the feasibility, inter-reader reliability, and intra-reader reliability for various morphological features reported to be related to iliotibial band friction syndrome (ITBFS) on knee magnetic resonance imaging (MRI). Methods: A total of 145 patients with a clinical diagnosis and knee MRI findings consistent with ITBFS were included in the "study group" and 232 patients without knee pathology on both physical examination and MRI were included in the "control group". Various morphologic features on knee MRI were assessed including the patella shape, patella height, lateral epicondyle anterior-posterior (AP) width, lateral epicondyle height, ITB diameter (ITB-d), and ITB area (ITB-a). Results: Patients in the study group had significantly higher lateral epicondyle height (13.9 mm vs. 12.92 mm, P = 0.003), ITB-d (2.9 mm vs. 2.0 mm, P = 0.022), and ITB-a (38.5 mm² vs. 23.8 mm², P < 0.001) than the control group. ITB-a showed higher area under the curve index (0.849 with 74.1% sensitivity and 72.4% specificity at a 30.3 mm² cutoff) than ITB-d (0.710 with 70.8% sensitivity and 61.2% specificity at 2.4 mm cutoff) and lateral epicondyle height (0.776 with 72.4% sensitivity and 67.8% specificity at 13.4 mm cutoff). However, only the inter-reader agreement for ITB-a (intraclass correlation coefficient = 0.65) was moderate, while the agreements for other morphologic features were good or excellent. Conclusions: Lateral epicondyle height seems to be a reliable and feasible morphologic feature for diagnosis of ITBFS.