• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.193-193
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• 2016

In past decades beach erosion has been remarkably severe along coasts of different parts of the world, so that distinct types of coastal protective measures have been implemented; seawalls, wave-dissipating breakwaters, groins, artificial headlands or detached breakwaters have been constructed. In recent years, at Bongpeong beach, South Korea, an artificial headland was constructed to stop the beach erosion. The structure resulted in severe beach erosion of the adjoining places. In order to stop the consequences, another headland was constructed at some distance, but the construction of double headland did not prevent the erosion significantly. This paper focuses on the accurate design of the artificial double headland construction. The study presents the application of equilibrium shoreline empirical formula of parabolic type to estimate the equilibrium stages of the artificial double headland beaches and an analytic solution is presented in the present study. The research has solved the empirical formula of parabolic type to find the optimum result by considering the essential parameters that influence the erosion after the construction of double headland.

• Journal of the Korea Safety Management & Science
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• v.25 no.3
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• pp.1-7
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• 2023

As the capacity of renewable power generation facilities rapidly increases, the variability of electric power system and gas turbine power generation is also increasing. Therefore, problems may occur that require urgent repair while the gas turbine rotor is stopped. When the gas turbine rotor turning is stopped and then restarted, if the turning period is not appropriate, severe vibration may occur due to rotor bending. As a result of the experiment, it was confirmed that normal operation is possible when the gap data measured at the start of rotor turning after maintenance work is similar to the existing value. And the vibration value at the start of rotor turning was lower as the rotor temperature was lower or the stop period was shorter.

• The Research Journal of the Costume Culture
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• v.20 no.5
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• pp.655-663
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• 2012

Due to increased interest in character costumes, the field of animation character costume design is gradually developing into a specialized domain. The costume-making process for animation characters presents many differences from the costume-making process for regular apparel. However, there remains insufficient research on the actual process of making the character costumes used in stop motion videos both in Korea and abroad. The purpose of this study is to establish a costume design process for animation characters. Furthermore, this study presents a case study on the costume planning and making process for 3D stop motion animation characters. The character costume-making process was segmentalized into the following stages: character analysis stage, character modeling stage, and character costume making stage. In the character analysis stage, the investigator analyzed the character's movements, designed the character images, and analyzed the movements and motions of the animation characters. After completing character modeling, this study proposed a method for making the character costume. The style of the character costume was designed, and the structural design reflected the position and size of joints as well as the angle of movements. The patterns of the character costume were produced through dimensional tailoring after measuring the body size of the character. Afterward, the costume was completed after passing through the fitting and revision stages. The clothing material was selected to fit the colors and feelings shown in the illustration. To complete the costume after comparing it with the initial illustration, it was revised based on the assessment of its volume and overall atmosphere.

• Journal of the Korean earth science society
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• v.26 no.1
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• pp.41-57
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• 2005

The purpose of the study is to develop a educational data in order for students to perform geologic field survey effectively by themselves. A area around the Duta Mountain is selected. which is located at the southeastern part of Eumsung sedimentary basin because various rock types and geologic structures are well shown in this area and also it is convenient to reach there. Thirteen stops for observation are chosen m a route f3r exercising field geologic investigation. Data for field research are given and described in detail from each stop for observation. To do this, students make their own route map using general or digital geographic map and aerial photo is added to know relationship between large-scale structure and different rock types regionally. Moreover, it is designed to minimize conflict factors that may be experienced from the real field survey by showing outcrop photographs and polarizing photomicrographs of rut samples related to each stop and geologic structures. The attitude of students is investigated with the data of field geologic survey for students of an Earth Science class in the College of Education in Chungbuk National University. The results indicate that the educational data for geologic field survey brought positive changes that greatly help students perform field survey in definitive side, especially formation of absolute concepts on earth science.

• Korean Journal of Optics and Photonics
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• v.28 no.6
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• pp.263-272
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• 2017

To design a wide-field optical system, the inverted telephoto configuration, which has a negative front group and a positive rear group, is popular. For a two-mirror system, the inverse Cassegrain system has the inverted telephoto configuration, but the inverse Cassegrain system with the conventional, axially symmetric configuration shows severe field screening and ray obstruction. To avoid these problems, we put the aperture stop on the secondary mirror of an inverse Cassegrain system to increase field of view, and designed a wide-field off-axis two-mirror system which only uses the off-axis field, without ray obstruction.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.11
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• pp.353-356
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• 1996

Early this year the construction of new high voltage power lines have been forced to stop due to the demonstration of residents in Kwa-chun. According to mutual agreement between the residents and Korea Electric Power Corporation, electromagnetic field(EMF) from present power lines was measured and EMF after completion of new power lines was estimated. The results show that EMF near power lines Is relatively low, and EMFnear electric substation is quite high due to the short distance between the power lines and ground. For 4 conduction 345kV line, magnetic field decreases to 3mG at the distance of 50m from the power line.

• Current Optics and Photonics
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• v.4 no.4
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• pp.336-344
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• 2020

Exact optical characterization of virtual and augmented reality devices using conventional luminance measuring methods is a time-consuming process. A new measurement method is proposed to estimate in a relatively short time the boundary of ray trajectories emitting from a specific position on a virtual images. It is assumed that the virtual image can be modeled to be formed in front of one's eyes and seen through some optical aperture (field stop) that limits the field of view. Circular and rectangular shaped virtual images were investigated. From the estimated ray boundary, optical characteristics, such as the viewing direction and three dimensional range inside which a eye can observe the specified positions of the virtual image, were derived. The proposed method can provide useful data for avoiding the unnecessary measurements required for the previously reported method. Therefore, this method can be complementary to the previously reported method for reducing the whole measurement time of optical characteristics.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.4 no.2
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• pp.12-17
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• 1995

The operation of heavy tracked vehicle has the problems in the steering that made by misoperations. The protection device is applied to the vehicles. But that device is applied to the vehicles. But that device has the engine stop and over load condition problems. the steering safety system is developed on the basis of clutch slip that proved the durability in the dynamo test and field test. The steering safety system caused the performance improvement of vehicles when steering.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1987.11a
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• pp.1-27
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• 1987

1. Gasoline engine sludge is a major worldwide problem 2. U.S. and European sludge have similarities 3. Stop-go driving and longer oil drains make the problem worse 4. Fuel is a major influencing factor 5. Increased use of cracked components may be cause 6. Sludge can be peproduced in controlled field tests 7. Daimler benz M102E and ford PV-2 (VE) tests have been developed to overcome problem by higher oil quality 8. The M102E and PV-2 respond in a similar way to increased dispersancy 9. High dispersant ocp viscosity modifiers appear to have unique adbantage in both tests

• Analytical Science and Technology
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• v.25 no.6
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• pp.476-482
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• 2012

Asian dust particles are known to have sizes ranging from a few nanometers up to about a few micrometers. The environmental and health effects depend on the size of the dust particles. The smaller, the farther they are transported, and the deeper they penetrate into the human respiratory system. Sedimentation field-flow fractionation (SdFFF) provides separation of nano to microparticles using a combination of centrifugal force and parabolic laminar flow in a channel. In this study, the steric mode of SdFFF (Sd/StFFF) was tested for size-based separation and characterization of Asian dust particles. Various SdFFF experimental parameters including flow rate, stop-flow time and field strength of the centrifugal field were optimized for the size analysis of Asian dust. The Sd/StFFF calibration curve showed a good linearity with $R^2$ value of 0.9983, and results showed an excellent capability of Sd/StFFF for a size-based separation of micron-sized particles.The optical microscopy (OM) was also used to study the size and the shape of the dust particles. The size distributions of the samples collected during a thick dust period were shifted towards larger sizes than those of the samples collected during thin dust periods. It was also observed that size distribution of the sample collected during dry period shifts further towards larger sizes than that of the samples collected during raining period, suggesting the sizes of the dust particle decrease during raining periods as the components adsorbed on the surface of the dust particles were removed by the rain water. Results show Sd/StFFFis a useful tool for size characterization of environmental particles such as the Asian dust.