• Journal of Korean Ophthalmic Optics Society
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• v.12 no.2
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• pp.1-12
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• 2007

Object of this research is to estimate the effect of myopia correction and safety on reverse geometry contact lens fitting in school children. This research include 53(106eyes) schoolchildren among 7 to 18 years who has low to moderate myopia(-1.00D~-5.00D) and prescribed reverse geometry contact lens for purpose on orthokeratology between January to July 2004 and had 3months full follow up examination. They were tested for slit lamp examinations, BUT(Break up time), direct ophthalmoscopy, retinoscopy, uncorrected visual acuity, best corrected visual acuity, autorefraction, autokeratometry and corneal topography in each examination(1day, 1week, 2weeks, 1, 2, and 3months) of before-and-after lens wearing to find out the effect of myopic correction and side effect. The results came out as follow. The average of uncorrected visual acuity was $0.0938{\pm}0.378$ before lens wear and $0.3136{\pm}0.283$ after 1day lens wear, and there was fast improvement after 1week($0.7925{\pm}0.301$) and little improvement after 2weeks period but still they shows better uncorrected visual acuity(p<0.01). The result of this study, the reverse geometry lens is very useful to correct refractive error and control the progression of myopia temporally among low to moderate myopic patient. The side effects were relatively rare but further study should be necessary with long term lens wear effect on eye health. For the lens prescription, the clinical fitting process had higher rate of success with consideration of eccentricity and corneal topography.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.4
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• pp.519-526
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• 2015

Purpose: To evaluate the changes of OSI value according to tear-film instability measured serially by OQAS(Optical Quality Analysis System, Visiometrics, Spain) every seconds. The presented study analyzed the relationship of the OQAS parameter with the results of the tear-film break-up time, Schirmer test, and the McMonies score. Methods: 147 eyes of 82 subjects were randomly selected from university students (age: $21.51{\pm}3.97$, male 45, female 37). Subjects were measured tear-film break-up time, Schirmer test, McMonies score and once every second for 15 seconds after blinking by continuous measurements from OQAS system. Results: The normal eye groups presented OSI values of $2.13{\pm}1.16$ while the dry eye groups had OSI values of $3.76{\pm}1.42$. Therefore, a significant difference between the normal eye group and dry eye group was discovered (p<0.05). In addition, the OSI value of all subjects increased over time. The OSI value, which was measured every second after blinking occurred, significantly increased between 6 seconds and 7 seconds after the start of the measurement (p<0.05). OSI cut off of 30% (sec.) showed a greater correlation; TBUT (r = 0.855, p = 0.000), McMonies test (r = -0.351, p = 0.003), Schirmer (r = 0.316, p = 0.012). Conclusions: Continuous measurement of OQAS showed a high correlation with the value of the existing dry eye tests. Therefore, Analysis of OSI values by utilization of OQAS could be useful in objectively evaluation of tear film in patients.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.5
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• pp.193-199
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• 2010

In this paper, we propose a new metric to measure the dynamic connection states of Ad Hoc network. The new metric measures the total path break up time $\sum_{i}T_i$, where $T_i$ is the time period during which maximum cluster distance exceeds the radio range. $T_i$ can be calculated from the maximum cluster distance function of time, which can be computed from the node position samples of mobility model. The proposed metric can be used as a total system metric as well as an individual connection metric.

• Journal of Bio-Environment Control
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• v.17 no.2
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• pp.150-156
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• 2008

The influences of night break by costly artificial light sources were investigated on the photo-morphogenesis and growth of leafy perilla (Perilla ocymoides L.). The irradiation of red, blue, and three-colored light for night break significantly increased the stem length and stem diameter compared to dark. Three-colored light gave the highest fresh and dry weight of stem, followed by red and blue light. Floral induction was suppressed up to 100 days after the night break, by red and three-colored light, but the plants grown under the dark or treated with blue light showed 85% and 31% flowering rate, respectively. The time needed for floral induction after night break was 60 days in dark and 80 days in blue light. The number of leaf, leaf area, and fresh weight per plant were the highest in red and three-colored light night break, followed by blue light and dark. The photosynthetic rate observed 80 days after night break was the highest in red light, followed by blue and three-colored light. A low light compensation point of $20\;{\mu}mol\;m^{-2}{\cdot}s^{-1}$ was observed in three-colored light, while red and blue light tended to show higher measurements.

• Proceedings of the KOR-KST Conference
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• 1996.06a
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• pp.3-22
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• 1996

To translate the goal of redeveloping Shanghai as one of the international hubs of economy, finance and trade in 2010, the foundation is to be created, and international standing as global city is to be established preliminarily. Transformation of urban functions and approach of "High starting position and jump over" will give impetus to promote Shanghai as an international metropolitan within fairy short period of time. To transform urban functions and translate" High starting position and jump over", certain links which have great impact on Shanghai's rising-up must be handled and normal approach to develop the city must be renovated to reach the goal of establishing an international city. Four strategic approaches as following are explored in this paper : $\bullet$ To transform urban function from industry only to integrated developments. $\bullet$ To break through administrative boundary and expand urban development space. $\bullet$ To develop centralized urban infrastructure framework. $\bullet$ And to erect modern life and culture facilities towards 21st century.

• 한국전산유체공학회:학술대회논문집
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• 2009.11a
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• pp.218-222
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• 2009

A level-set (LS) method is presented for computation of boiling phenomena which involve liquid-vapor interfaces that evolve, merge and break up in time, the flow and temperature fields influenced by the interfacial motion, and the microlayer that forms between the solid and the vapor phase near the wall. The LS formulation for tracking the phase interfaces is modified to include the effects of phase change on the liquid-vapor interface and contact angle on the liquid-vapor-solid interline. The LS method can calculate an interface curvature accurately by using a smooth distance function. Also, it is straightforward to implement for two-phase flows in complex geometries. The numerical method is applied for analysis of nucleate boiling on a horizontal surface and film boiling on a horizontal cylinder.

• Journal of the korean Society of Automotive Engineers
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• v.7 no.4
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• pp.57-66
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• 1985

This paper deals with an experimental study on a liquid atomization to investigate the break- up mechanism of a liquid film flow which is formed by a high speed air flow in parallel direction and an atomization characteristics of a liquid film flow in order to provide the basic data for the development of the twin fluid atomizer. Authors had built the simplified, transparent new devices which can form a uniform thickness of liquid film and an electrical measuring circuit of the liquid film thickness. By introducing the new devices and the measuring circuit, the time variation of a liquid film thickness the mean diameter of the droplets, the droplet size distribution, the degree of the dispersion and the atomization rate of a liquid film are measured experimentally. As the analysis of the study, it can be said the experimental investigation will fairly contribute for further study in this field of study.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.451-452
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• 2008

In this paper we describe a multi-module, multi-port memory design procedure that satisfies area and/or energy constraints. Our procedure uses ILP models to determine (a) the memory configuration with minimum area, given the energy bound, (b) the memory configuration with minimum energy, given the area bound. If we have a margin in time constraint, we break up conflict edges and expend the search space of ILP. This method effectively reduces area and power of the designed results.

• Journal of the Korea Furniture Society
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• v.24 no.3
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• pp.263-272
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• 2013

This study is the content of the environment-friendly is the tendency of one of postmodernism. Rather than end up post-modernism in the past, such trend has affected many in the design of modern furniture. Appeal to emotion in order to achieve an intimate relationship with the user, especially in the new material, you are the fulfillment of desire more than a simple function. In addition, designers of modern Many or even looking from the re-interpretation of the design past the motif of the design such as the time that post-modernism has arrived. Users who are using the furniture, because there is a tendency to features In addition to the primary that it has, you have to Want the meaning of one another, and to Serve by generating story distance from him this some. In this study, to target households that still is very important in modern design, and a historic of postmodernism the concept with a different meaning functional, the figurative to break free from meaning one-dimensional with the furniture I was analyzed on the basis of the flow.

• Journal of Welding and Joining
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• v.15 no.3
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• pp.47-55
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• 1997

Dynamic characteristics of the short circuit mode are investigated using the Volume of Fluid (VOF) method. When the initial molten drop volume, contact area and wire feed rate are given, rate change of the molten bridge profiles, pressure and velocity distributions are predicted. The electromagnetic force with proper boundary conditions are included in the formulation to consider the effects of welding current. It is found that the molten metal is transferred to the weld pool mainly due to the pressure difference caused by the curvatures in the initial stage, and electromagnetic force becomes dominant factor in the final stage of short circuit transfer. Necking occurs at the contact position between the molten drop and weld pool, and the initial molten drop volume and welding current have significant effects on break-up time.