• Progress in Superconductivity and Cryogenics
• /
• v.24 no.3
• /
• pp.19-23
• /
• 2022

We have been developing a magnetic separation device that can be used in low magnetic fields for paramagnetic materials. Magnetic separation of paramagnetic particles with a small particle size is desired for volume reduction of contaminated soil in Fukushima or separation of iron scale from water supply system in power plants. However, the implementation of the system has been difficult due to the needed magnetic fields is high for paramagnetic materials. This is because there was a problem in installing such a magnet in the site. Therefore, we have developed a magnetic separation system that combines a selection tube and magnetic separation that can separate small sized paramagnetic particles in a low magnetic field. The selection tube is a technique for classifying the suspended particles by utilizing the phenomenon that the suspended particles come to rest when the gravity acting on the particles and the drag force are balanced when the suspension is flowed upward. In the balanced condition, they can be captured with even small magnetic forces. In this study, we calculated the particle size of paramagnetic particles trapped in a selection tube in a high gradient magnetic field. As a result, the combination of the selection tube and HGMS (High Gradient Magnetic Separation-system) can separate small sized paramagnetic particles under low magnetic field with high efficiency, and this paper shows its potential application.

• Progress in Superconductivity and Cryogenics
• /
• v.25 no.3
• /
• pp.13-17
• /
• 2023

Magnetic separation technology for small paramagnetic particles has been desired for the volume reduction of contaminated soil from the Fukushima nuclear power plant accident and for the separation of scale and crud from nuclear power plants. However, the magnetic separation for paramagnetic particles requires a superconducting high gradient magnetic separation system applied, hence expanding the bore diameter of the magnets is necessary for mass processing and the initial and running costs would be enormous. The use of high magnetic fields makes safe onsite operation difficult, and there is an industrial need to increase the magnetic separation efficiency for paramagnetic particles in as low a magnetic field as possible. Therefore, we have been developing a magnetic separation system combined with a selection tube, which can separate small paramagnetic particles in a low magnetic field. In the previous technique we developed, a certain range of particle size was classified, and the classified particles were captured by magnetic separation. In this new approach, the fluid control method has been improved in order to the selectively classify particles of various diameters by using a multi-stage selection tube. The soil classification using a multi-stage selection tube was studied by calculation and experiment, and good results were obtained. In this paper, we report the effectiveness of the multi-stage selection tube was examined.

• Journal of the Korea Society of Computer and Information
• /
• v.26 no.12
• /
• pp.273-281
• /
• 2021

In this paper, we propose a ways how YouTube Mukbang content attributes affect favorability, satisfaction, and brand selection, and suggest to use YouTube Mukbang contents, and to propose a strategic marketing plan using YouTube at the food franchise. This study conducted survey on 218 people who had watched chicken Mukbang among YouTube Mukbang contents. Through previous studies, YouTube content attributes were classified into informativity, entertainment, reliability, and attractiveness. To verify the hypothesis of the study, single regression and multiple regression analysis were conducted for verifying the relationship between variables. Key results of the study are as follows. First, it was found that YouTube Mukbang content attributes had a positive relationship with favorability. Second, it was found that YouTube Mukbang content attributes had a positive relationship with satisfaction. Third, it was found that favorability had an effect on satisfaction. Fourth, it was found that favorability influenced brand selection. Fifth, it was found that satisfaction did not affect brand selection. Based on these findings, a strategic approach will be needed to increase users' favorability by providing attractive and accurate information through YouTube Mukbang contents and to continuously improve brand choices through continuous favorability to revitalizing YouTube marketing at the food franchise.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.7 no.4
• /
• pp.681-693
• /
• 1995

A new set of capillary tube selection charts for R-22 is proposed. The set of charts takes into account of the roughness effect on the mass flow rate. For this purpose, a set of numerical model is developed and a series of experiments is conducted to verify the numerical model. A numerical model is used to calculated the mass flow rate for several sets of tube diameter, length, inlet pressures and degree of subcooling. The outlet of the tube is controlled to be at critical condition. The experimental flow rate is compared with calculated values. The calculated values are consistently less than the experimental ones except for the flow rate range below 40kg/hr. The deviation is within 10---. Based on the nunmerical model and results of experiments, the set of capillary tube selection charts for R-22 is constructed. The set of charts consists of standard capillary tube chart(L=2030mm, d=1.63mm, ${\varepsilon}=2.5{\mu}m$), non -standard flow factor(${\phi}_1$) chart, and non-standard roughness factor(${\phi}_2$) chart. The mass flow rate, flow factor, and the roughness factor are defined respectively as; $\dot{m}={\phi}_1{\phi}_2\dot{m}_{standard}\\{\phi}_1=\frac{\dot{m}(L,\;d,\;\varepsilon_{standard})}{\dot{m}_{standard}(L_{standard},\;d_{standard},\;{\varepsilon}_{standard})}\\{\phi}_2=\frac{\dot{m}(L_{standard},\;d_{standard},\;{\varepsilon})}{\dot{m}_{standard}(L_{standard},\;d_{standard},\;{\varepsilon}_{standard})}$.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.10 no.1
• /
• pp.56-65
• /
• 1998

In this paper, experimental investigation of capillary tube performance for R-407C is performed. The experimental setup is made of real vapor-compression refrigerating system. In this study, mass flow rate is measured for capillary tubes of various diameter and length as inlet pressure and degree of subcooling are changed. These data are compared with the results of a numerical model. The mass flow rates of the numerical model are less than by 14% compared with the measured mass flow rates. It is found that mass flow rate and length for R-407c are less than those of R-22 under the same condition. Also based on this experimental study and the numerical model, a set of capillary tube selection charts for R-407C is constructed.

• Proceedings of the KSME Conference
• /
• 2007.05a
• /
• pp.751-755
• /
• 2007

The purpose of this study is to find the optimization processing on expanded tube using Taguchi method which was generally used to analyze the effects of various control factors. Mini-Tab is a good for program that is making a selection using Taguchi method. The results of experimental test and analysis are as follows. Optimization processing on a expanded tube is dependent on lubrication condition. The slight eccentricity of expanded tube was obtained a good results on the expanded tube. When expending processing on the expanded tube was performed, the test specimens were almost unaffected by changing pressure loading. The tendencies of test results were related to lubrication condition and eccentricity in expending processing. As a result, a proper lubrication condition and eccentricity in the step of design will improve the optimization processing of expanded tube.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2022.05a
• /
• pp.209-211
• /
• 2022

YouTube, a video platform used by millions of people worldwide, provides a rapidly growing video service. This study aims to understand the characteristics and cultural differences of each country using the Kaggle dataset, one of the public datasets, and to show the usefulness of the public dataset. For this purpose, we analyze data from 11 countries, 15 categories, and about 1.1 million trending videos. This study adopts Python to obtain the number of videos by category for data analysis, the selection period of videos rapidly increasing in popularity, and the ratio of unique videos. In the future, based on machine learning, we plan to research to help diagnose individual videos and establish channel operation plans and strategies by predicting the selection possibility and selection period based on machine learning.

• The Korean Journal of Zoology
• /
• v.26 no.2
• /
• pp.95-106
• /
• 1983

Selections for rapid and slow walking behavior were carried out with the populations, drived from Oregon-R and lethal free strain of Drosophila melanogaster. The behavior was measured by means of connected test-tube apparatus. The populations responded effectively to the artificial selection, and it reached the selection plateau after 7 generations. The realized heritability for the first 10 generations was estimated to be about $9\\sim14%$ for the rapid walking behavior, and those for slow walking behavior was about $11\\sim16%$. The results of hybridization analysis between selected populations at generations 8 and 10 indicated that some polygenes showing a slow walking behavior were partially dominant over polygenes controlled rapid trait. The populations selected for rapid and slow walking behavior were relaxed after 10 generations of selection. The response to natural selection of rapid population was completely returned to their neutral states after only 5 generations. Such phenomena would be explained by the genetic homeostasis resulted from an action of natural selection. However, the slow population did not make any difference from walking scores of their original artificial selection. It seems reasonable to assume that the slow walking behavior was possibly controlled by a major gene.

• Journal of Veterinary Clinics
• /
• v.35 no.5
• /
• pp.184-189
• /
• 2018

Wild birds rescued for various reasons are injured and admitted to a wild animal rescue center. With the case of collision with cars, buildings and wires on a power pole, most wild birds are severely traumatized or get fractured, which need intensive veterinary treatment. In general, inhalation anesthesia to wild birds is the best choice for the medical and surgical procedure, and intubation is recommended for the stable anesthesia. Although the certain size of an endotracheal tube can be chosen depending on the size and morphology of the bird, there are a few standardized guidelines. Therefore, the optimal endotracheal size of the rescued 162 individual birds of 41 species for four years from March 2014 to December 2017 was investigated and sorted empirically, suggesting possibly the appropriate endotracheal sizes for diverse avian species. It may provide practical information data for wildlife veterinarians to select the size of an endotracheal tube according to the size of the domestic wild bird species, especially during surgery in the emergency cases.

• Nuclear Engineering and Technology
• /
• v.34 no.4
• /
• pp.358-369
• /
• 2002

Abundant information about analyses of single steam generator tube rupture (SGTR) events is available because of its importance in terms of safety. However, there are few literatures available on analyses of multiple steam generator tube rupture (MSGTR) events. In addition, knowledge of transients and consequences following a MSGTR event are very limited as there has been no occurrence of MSGTR event in the commercial operation of nuclear reactors. In this study, a postulated MSGTR event in an APR1400 is analyzed using thermal-hydraulic system code MARSI.4. The present study aims to examine the effects of affected steam generator selection. The main steam safety valve (MSSV) lift time for four cases are compared in order to examine how long operator response time is allowed depending on which steam generate. (S/G) is affected. The comparison shows that the cases where two steam generators are simultaneously affected allow longer time for operator action compared with the cases where a single steam generator is affected. Furthermore, the tube ruptures in the steam generator where a pressurizer is connected leads to the shortest operator response time.