• Journal of the Korean GEO-environmental Society
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• v.11 no.8
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• pp.57-63
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• 2010

For optimum scale design of containment area, a series of laboratory tests using column were performed in this study as followings; sedimentation test and self-weight consolidation test for dredged soil, and suspended solid concentration test for supernatant. Containment area has been designed and evaluated, based on field condition and concentration of suspended solid of effluent water. In addition, the relation between width of containment area and target concentration of suspended solid was analyzed. The results show that concentration of suspended solid decreases as the width of containment area decreases and the length of containment area increases. It was also observed that influence of change in ponding depth should be considered to predict the change in suspended solid concentration in supernatant discharged as disposal is conducted; the lower target suspended solid concentration of effluent water, the more important.

• Journal of Welding and Joining
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• v.31 no.1
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• pp.51-57
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• 2013

Residual stress caused in the weldments with high restraint force are often observed during welding in the weldments of Inner and outdoor materials or radial tanks. The reason is that quantitative analysis about thermal stresses during laser welding is lacking for this weldments. To verify Finite Elements Method (FEM) theory, the temperature was measured with thermocouple in a real time in this paper. Also analysis of the thermal stress for welding condition is performed by Comsol program package on various welding condition in SCP1-S butt welding. The principal stress in laser welding process is seen through the width direction. Also, it was confirmed that a change in base metal by thermal expansion made the stress in width direction stronger. Base metal close to the weld bead as the process progresses to the tensile stress in the compressive stress was varied. It was shown that the change of stress was quantitative from the bead at a certain distance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.04b
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• pp.10-11
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• 2008

We developed the equipment palpating cell proliferation using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity, frequency and so on. Especially, to control the light irradiation frequency, FPGA was used, and to control the change of output value, TLC5941 was used. Control stage is divided into 30 levels by program. Consequently, the current value could be controlled by the change of level in Continue Wave(CW) and Pulse Width Modulation(PWM), and the output of a high brightness LED could be controlled stage by stage. And then, each experiment was performed to irradiation group and non-irradiation group for bone marrow cells. MIT assay method was chosen to verify the cell increase of two groups and the effect of irradiation on cell proliferation was examined by measuring 590nm transmittance of ELISA reader. As a result, the cell increase of bone marrow cells was verified in irradiation group as compared to non-irradiation group.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.26 no.2
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• pp.45-63
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• 1996

In attempt to determine radiation effect on the mandibular condyle of the growing rat, 27 white female rats (Sprague-Dawley) were divided into 3 groups and irradiated respectively 5Gy, 10Gy, 20Gy using MK Cell Irradiator. Mandibular condyles from rats on the day of 1, 7, 14 after the irradiation day were obtained, sectioned sagittally and examined by light microscopy, and thereafter middle portion through anteroposterior direction on the sagittal plane was selected to examine the ultrastructural change by transmission electron microscopy. The obtained results are followings. 1. In the proliferative zone some cells showed little organelles in case of 5Gy irradiation, in addition the number of degenerative cells increased and in case of 10Gy irradiation, and in case of 20 Gy irradiation total number of cells decreased. 2. In the hypertrophic zone, narrowing of width and partial disorder in hypertrophic process were noted in case of 5 Gy irradiation, and more prominent narrowing of width and more irregular disorder in hypertrophic process in case of both 10Gy and 20Gy irradiation. 3. In the upper hypertrophic zone some chondrocytes seemed to be dying and the polarity of nuclei could not be seen, if any. 4. The periodic observation showed the severest change at day 7 and the signs of recovery at day 14 after irradiation.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.8
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• pp.1378-1385
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• 2001

Textile The purpose of this research is to develop the design for activation of women s hanbok focused on functionality and convenience as well as on keeping the traditional beauty, and then to produce them. As a result of these explorations, I have reached conclusions as follows. first, the transformation of jackets and skirts are mainly limited to partial change in elements of the dress design-width and length of a jacket string and the upper strip on the outside of a jacket, change in width, and granting of symbolic meaning. Second, aesthetic features and formative beauty of traditional hanbok that the harmonization of mainstream colors and highlighting colors and curved silhouettes evoke were mental by products created as our people wished to become friendly to and to harmonize with nature. Third, grounded upon study of lines form and survey on brands, I have developed designs that maintain hanbok’superiority and at the same time incorporate functionality and convenience to fit modern life. I believe that the outcome of these of these explorations will contribute greatly to carrying the traditional beauty of Korean dresses to the maximun, and to developing and popularizing functional and practical living-fitted Korean dresses.

• Journal of Sensor Science and Technology
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• v.27 no.6
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• pp.421-426
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• 2018

To develop a piezoelectric inkjet printhead for high-resolution and high-speed printing, we studied the characteristics of an inkjet printhead by analyzing the major design parameters. An analytical model for the inkjet printhead was established, and numerical analysis of the coupled first-order differential equation for the defined state variables was performed using state equations. To design the dimension of the inkjet printhead with a driving frequency of 100 kHz, the characteristics of the flow rate and discharge pressure of the nozzle were analyzed with respect to design variables of the flow chamber, effective sound wave velocity, driving voltage, and voltage waveform. It was predicted that the change in the height of the flow chamber does not significantly affect the Helmholtz resonance frequency and discharge speed of the nozzle. From the analysis of change in flow chamber width, it is observed that as the width of the flow chamber increases, the ejection speed greatly increases and the Helmholtz resonance frequency decreases considerably, thereby substantially affecting the performance of the inkjet printhead.

• Journal of the Korean Institute of Rural Architecture
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• v.14 no.3
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• pp.93-100
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• 2012

The purpose of this study is to examine the change of inner roads responding to the street system and to examine the how to influence to communal space of village focused on 22 existing old settlements in downtown Cheong Ju. This study examined the types of inner roads based on advanced research. For the research on communal space, interviews with the residents living in the village were conducted to figure out the location and function of it. Also, it was analyzed comparatively with the present communal space. The results are as followings: the width of an inner road has a effect to function of an inner road when flow of an inner road has kept. The function of inner road has been kept when the width of an inner road expanded as pedestrians should be given priority to vehicular traffic. However, the function of inner roads has been changed and the community has been separated when the width of inner roads expanded for vehicular. Because the location of the communal space in the village is affected by the change of the inner road, when the inner road is maintained, the location of the communal space is also maintained, but when the inner road is changed, the location of the communal space is also changed. The communal spaces such as public wells and wash spaces have lost and they have been substituted with senior citizen centers or community centers.

• The Korean Journal of Mycology
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• v.20 no.4
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• pp.309-314
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• 1992

Nine species of powdery mildew fungi were examined to understand the change in size of conidia in relation to air temperature. Of these, Sphaerotheca aphanis, S. fusca and S. pannosa showed constant value of conidial sizes regardless of changes in air temperature. The length/width ratio in the conidia of Erysiphe, artemisiae and E. sordida increased as the air temperature rose. E. cichoracearum gave the result against that shown in the above two species of Erysiphe. The conidia of Microsphaera pseudolonicerae became decreased in their width as the air temperature fell. The length/width ratio of conidia was markedly increased. M. alphitoides and M. robiniae showed variable size measurements in conidia regardless of changes in air temperature and studies for it needed for additional examination in future.

• Journal of Periodontal and Implant Science
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• v.31 no.3
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• pp.531-542
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• 2001

Periodontal debridement is most important procedure in periodontal treatment, because periodontal disease is the biofilm infection. The use of ultrasonic instrument has many clinical advantages compared to classical hand instrument. The introduction of newly developed ultrasonic scaler tips made the use of ultrasonic scaler popular. However the study of tooth substance removal according to the working parameters of ultrasonic scaler with newly developed tips is not sufficient. The purpose of this study is to evaluate the effects of working parameters of piezoelectric ultrasonic scaler with curette tip on casting gold removal. The working parameters was standardized by the sledge device which controls lateral force(0.5 N, 1.0 N, 2.0 N) and power setting was adjusted 2, 4, 8 in P mode and S mode and instrumentation time was 5 seconds. The defect depth and width were measured with profile meter and defect surface was examined by SME. The depth of defect was significantly large in S mode( $39.58{\pm}19.35{\mu}m$) compared to P mode( $8.37{\pm}6.98{\mu}m$). There was significant decrease of depth of defect between 1.0N($32.87{\pm}27.18{\mu}m$) and 2.0N( $14.86{\pm}15.04{\mu}m$). The area of defect was also significantly large in S mode($4482.42{\pm}3551.71{\mu}m^2$) compared to P mode( $922.06{\pm}960.32{\mu}m^2$). There was significant decrease of area of defect between 1.0N($3889.12{\pm}3936.00{\mu}m$) and 2.0N( $974.66{\pm}986.01{\mu}m$). The change of mode did not effect on the width of the defect. The change of power setting did not effect on the depth, width, and area of defect. In spite of limitation of this study it could be concluded that the use of piezoelectric ultrasonic scaler with curette tip on S mode could make significant tooth substance loss.

• Fire Science and Engineering
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• v.31 no.4
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• pp.26-34
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• 2017

The purpose of this study is to identify and improve the performance of the adjacent room ventilation system in living room ventilation facilities, and compare and analyze the smoke control regulations of the NFPA code and the national fire safety standard (NFSC). The analysis method was fire dynamics simulation (FDS) and was used to analyze the, variations of the air supply amount, width of the boundary, change in indoor combustion and wind velocity of the incoming air. It was found to be advantageous to secure the clean layer when the amount of air supplied is less than the amount of discharged air in the fire room. However, in the supply room, it is more effective to secure the clean layer when the amount of supplied air is larger than the amount of discharged air, as a longer boundary width gives rise to better performance. In addition, it is necessary to consider the amount of air supplied and discharged as a function of the kind of flammable material. Moreover, decreasing the air inlet wind speed and amount of incoming air is advantageous for securing the clean layer of the fire room.