• Investigative Magnetic Resonance Imaging
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• v.21 no.2
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• pp.109-113
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• 2017

A 55-year-old male presented with dysesthesia of the right anteromedial thigh. A magnetic resonance image revealed a globular mass at the right extraforaminal area of the L3/4 level. Based on the diagnosis of neurogenic tumor, surgical excision was performed. The surgical impression and pathology confirmed extrusion of intervertebral disc. In a retrospective review of the magnetic resonance image, we noticed a fibrillary pattern directed from the intervertebral disc space to the lesion, and disrupted annulus fibrosus and indentation caused by the ring apophysis. We suggest aforementioned features, indicative of intervertebral disc lesions, to be checked when interpreting mass lesions around the intervertebral foramen.

• JSTS:Journal of Semiconductor Technology and Science
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• v.10 no.4
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• pp.316-324
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• 2010

In this paper, we design a 256 kbits EEPROM for a MCU (Microcontroller unit) with the wide voltage range of 1.8 V to 5.5 V. The memory space of the EEPROM is separated into a program and data region. An option memory region is added for storing user IDs, serial numbers and so forth. By making HPWs (High-voltage P-wells) of EEPROM cell arrays with the same bias voltages in accordance with the operation modes shared in a double word unit, we can reduce the HPW-to-HPW space by a half and hence the area of the EEPROM cell arrays by 9.1 percent. Also, we propose a page buffer circuit reducing a test time, and a write-verify-read mode securing a reliability of the EEPROM. Furthermore, we propose a DC-DC converter that can be applied to a MCU with the wide voltage range. Finally, we come up with a method of obtaining the oscillation period of a charge pump. The layout size of the designed 256 kbits EEPROM IP with MagnaChip's 0.18 ${\mu}m$ EEPROM process is $1581.55{\mu}m{\times}792.00{\mu}m$.

• Progress in Superconductivity and Cryogenics
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• v.18 no.1
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• pp.64-68
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• 2016

High Temperature Superconductor power cable systems are being developed actively to solve the problem of increasing power demand. With increases in the unit length of the High Temperature Superconductor power cable, it is necessary to develop highly efficient and reliable cryogenic pumps to transport the coolant over long distances. Generally, to obtain a high degree of efficiency, the cryogenic pump requires a high pressure rise with a low flow rate, and a partial emission type pump is appropriate considering its low specific speed, which is different from the conventional centrifugal type, full emission type. This paper describes the design of a partial emission pump to circulate subcooled liquid nitrogen. It consists of an impeller, a circular case and a diffuser. The conventional pump and the partial emission pump have different features in the impeller and the discharge flow passage. The partial emission pump uses an impeller with straight radial blades. The emission of working fluid does not occur continuously from all of the impeller channels, and the diffuser allows the flow only from a part of the impeller channels. As the area of the diffuser increases gradually, it converts the dynamic pressure into static pressure while minimizing the loss of total pressure. We used the known numerical method for the optimum design process and made a CFD analysis to verify the theoretical performance.

• Progress in Superconductivity and Cryogenics
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• v.22 no.4
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• pp.57-61
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• 2020

Cooling by gas helium circulation can be used for various HTS (high temperature superconductor) magnets operating at 20~40 K, and a cryogenic blower is an essential device for circulating gas helium in the cooling system. The performance of the cryogenic blower is determined by various design parameters such as the impeller diameter, the blade number, the vane angle, the volute cross-sectional area, and the rotating speed. The trailing edge angle and the height of impeller vane are also key design factors in determining the blower performance. This study describes the design, fabrication and performance evaluation of cryogenic blower to produce a flow rate of 30 g/s at 5 bar, 35 K gas helium. The impeller shape is designed using a specific speed/specific diameter diagram and CFD analysis. After the fabrication of the cryogenic blower, a test equipment is also developed using a GM cryocooler. The measured flow rates and the pressure differences are compared with the design values at various rotating speeds and the results show a good agreement. Isentropic efficiency is also evaluated using the measured pressures and temperatures.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.1
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• pp.114-127
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• 2010

The purpose of this study is to find out cold and fresh air producing areas using climate-ecological functions in Changwon city, Gyeongsangnam-do, South Korea. The evaluation of climate-ecological functions were composed of the six factors: patch size with cold air generation and inflow functions, farmland and grassland ratio, mean slope degree, cross section types, mean slope length and roughness of bottom in valley. The analysis results of each evaluation factor in the study area were divided into 5 grades according to the capacity of cold air generation. The first-grade area with the highest factor values for cold air generation was take up 3.51% of the total study area, second grade was 13.48%, third grade was 31.65%, fourth grade was 27.28%, and fifth grade was 24.09%. According to the spatial distribution of cold air producing areas, the valleys around Mt. Bongnim, Changwon tunnel, and Anmin tunnel had higher evaluation grade. It will require the future research to establish the climate-ecological conservation areas and to construct the wind corridor based on the long-term microclimatic monitoring.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.8
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• pp.1914-1924
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• 2014

In this paper, a small-area cell array method of reducing number of SL drivers requiring large layout areas, where the SL drivers supplying programming currents are routed in the row direction in stead of the column direction for eFuse OTP memory IPs having less number of rows than that of columns such as a cell array of four rows by eight columns, and a core circuit are proposed. By adopting the proposed cell array and core circuit, the layout area of designed 32-bit eFuse OTP memory IP is reduced. Also, a V2V ($=2V{\pm}10%$) regulator necessary for RWL driver and BL pull-up load to prevent non-blown eFuse from being blown from the EM phenomenon by a big current is designed. The layout size of the designed 32-bit OTP memory IP having a cell array of four rows by eight columns is 13.4% smaller with $120.1{\mu}m{\times}127.51{\mu}m$ ($=0.01531mm^2$) than that of the conventional design with $187.065{\mu}m{\times}94.525{\mu}m$ ($=0.01768mm^2$).

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.2
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• pp.1-20
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• 2020

The purpose of this study was to analyze the distribution characteristics of spatial and temporal PM_2.5 in urban areas of Changwon-si, and to identify the causes of PM_2.5 by comparing the characteristics of land-use, and to suggest the direction of reduction measures. As the basic data, the every hour average from September 2017 to August 2018 of Airpro data, which has measurement points in kindergartens, elementary schools, and some middle and high schools in Changwon-si was used. Also, by using IDW method among spatial interpolation methods of GIS, monthly and time-slot distribution maps were constructed, and based on this, spatial and temporal PM_2.5 distribution characteristics were confirmed. First, to verify the accuracy of the Airpro data, the correlation with AirKorea data managed by the Ministry of Environment was confirmed. As a result of the analysis, R² was 0.75~0.86, showing a very high correlation and the data was judged that it was suitable for the study. In the monthly analysis, January was the highest year, and August was the lowest. As a result of analysis by time-slot, The clock-in time at 06-09 was the highest, and the activity time at 09-18 was the lowest. By administrative district, Sangnam-dong, Happo-dong, and Myeonggok-dong were the most severe regions of PM_2.5 and Hoeseong-dong was the lowest. As a result of analyzing the land-use characteristics by administrative area, it was confirmed that the ratio of traffic area and commercial area is high in the serious area of PM_2.5. In conclusion, the results of this study will be used as basic data to grasp the characteristics of PM_2.5 distribution in Changwon-si. Also, it is thought that the severe regions and the direction of establishing reduction measures derived from this study can be used to prepare more effective policies than before.

• Journal of Welding and Joining
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• v.19 no.6
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• pp.636-642
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• 2001

Partial penetration welding joint defines the groove welds that applies the one side welding which does not use steel backing and both side welding without back gouging, that is, the partial penetration welding joint leaves an unwelded portion at the root of the welding area. In this study, we analyzed the residual stress and fracture on the thick metal plates that introduced the partial penetration welding method. As results of using above mentioned welding method, we could draw a conclusion that longitudinal stress and traverse stress occurred around the welding area was so minimal and did not affect any influence. We also performed the fracture behavior evaluation on the partial penetration multi-pass welding with 25.4mm thick plate by using theJ-integral, which finally led us the conclusion that the partial penetration multi -pass welding method is more applicable and effective in handling the root face with less than 6.35mm.

• Journal of the Korean Home Economics Association
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• v.25 no.4
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• pp.123-139
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• 1987

A study on the House wife's Family Relation Satisfaction. This study aimed to investigate house wives satisfaction of their family relation. Major research question are as followings; 1. How do housewives satisfy their family relations? 2. What are difference in housewives satisfaction to such family relation areas. Marital relation, children relation, husband's parents relation, relative relation, and husband sister relation. 3. What are difference in housewives family relation satisfaction in terms of housewives personal variables (age, education, employment, husband job, family life cycle, family type…etc) The Subject of this study consisted of 863 housewives sampled in pusan, changwon area. The questionnaire which used in this study is made by the researcher. The data are analyzed statis factly. The finding of this study are as followings: 1. Home makers were found to show the high-satisfaction is 28.5%, the middle-satisfaction is 57.5% and the low satisfaction is 14.0%. And Pusan higher than changwon. T-test showed the significance according to Area(p<.05) 2. The satisfactioon of family-relations areas was showed that pusan higher than changwon homemakers on whole field. 3. The main factors which affected the state of satisfaction about their family-relations were their economical level, the state of employed of homemakers, the type of family.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.26 no.3
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• pp.342-349
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• 2016

Objectives: The objective of this paper is to find flow and heat transfer characteristics numerically in boiler buildings for three different ventilation window configurations. Methods: Turbulent natural convection flow in boiler buildings with a constant heating wall temperature was analyzed numerically. Governing equations were solved with standard finite-volume method using the SIMPLE algorithm. Conclusions: Flow and heat transfer characteristics are found for three different ventilation types. In the lower area under furnace, velocity and temperature distributions show similar patterns among the three different ventilation types. In the upper area over furnace, however, air flow is well mixed with lower peak temperatures for types B and C, which have roof ventilation windows, compared to type A which has side wall louvers only. Also, type B, with a single large roof window, shows better ventilation effect than does type C with its distribution roof windows.