• Journal of the Korean earth science society
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• v.31 no.7
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• pp.708-719
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• 2010

The Gochang-gun Dongho macro-tide pocket-type beach, located on the southwestern coast of Korea, is investigated in terms of the seasonal variations of surface sediment and sedimentary environment. Surface sediments of 45 sites in four seasons (May 2006-February 2007) are sampled across three survey lines (15 sites in each survey line). The surface sediments of the Dongho Beach are mainly composed of fine to coarse sands, and the ratio of fine sand is the largest. The average of grain size is the coarsest in the summer. The spatial distribution of surface sediments shows a coast-parallel band of fine and medium sands during three seasons of spring, fall, and winter, whereas medium sands dominated in the northern part of the study area during the summer. These results suggest that a tide is more effective than a wave in the surface sediments of the Dongho Beach during the summer.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.2
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• pp.28-33
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• 2017

Recently, the operation of precision pocket machining has been studied for the high speed and accuracy in industry to increase production and quality. Moreover, the demand for products with complex 3D free-curved surface shapes has increasing rapidly in the development of computer systems, CNC machining, and CAM software in various manufacturing fields, especially in automotive engineering. The type of aluminum (Al6061) that is widely used in aerospace fields was used in this study, and end-mill down cutting was conducted in fillet cutting at a corner with end-mill tools for various process conditions. The experimental results may demonstrate that the end mill cutter with four blades is more advantageous than that of the two blades on shape forming in the same condition precise machining conditions. It was also found that cutting forces and tool deformation increased as the cutting speed increased. When the tool was located at $45^{\circ}$ (four locations), the corner was found to conduct the maximum cutting force rather than the start point of the workpiece. The experimental research is expected to increase efficiency when the economical precision machining methods are required for various cutting conditions in industry.

• Journal of Korean Society of Steel Construction
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• v.16 no.4 s.71
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• pp.425-432
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• 2004

Large studs were suggested not only for the design of steel-concrete composite bridges with simplified sections but also for the shear connection in precast decks requiring uniform distribution of shear pockets. Based on the push-out test results on studs with diameters of more than 25 mm, partial composite beams with 40%-degree shear connection were fabricated, and static tests were performed. The ultimate strength and horizontal shear load redistribution of partial composite beams, which have parameters of stud shank diameters and distribution, were evaluated, and group failure in the shear span was observed. Since the flexural strength of composite beams are dependent on the strength of their shear connection, the strength of the stud connection was estimated and it showed considerably higher shear strength. From the load-slip curves, the sufficient ductility and load redistribution of large studs were confirmed. Uniformly distributed large studs can provide proper ultimate behavior of composite beams.

• The Journal of the Korea Contents Association
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• v.6 no.8
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• pp.57-67
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• 2006

The motion effect of animation can be maximized by using the intended number of frame(flickering phenomena) responding to the viewer's perception in the production processes. But, the high contrast of chroma in a color arrangement can cause very dangerous situation if a particular effect(scheduled number of frame for the intended rapid flickering in a zoom-in scene of the warning light of police car and the traffic light) or a excessive visual stimulus is tried. The danger of flickering phenomena is defined as 'Flash Nervousness Attack Symptom' in medical terminology, which has received wide attention because the damage to the viewers of Pocket Monster was very serious in Japan. Producing a piece of animation work, the quality control of colors is important but the color setting considering the psychological aspects, the danger of repetitive flickering of flashes and patterns in image effect are more serious, so these factors should be checked in the production stages. After investigating the domestic and foreign prescriptions including the guidelines for animation production technique in Japan, a solution to reduce the danger of flickering phenomena of color and light was suggested through statistical comparative analysis with the test results.

• Cartoon and Animation Studies
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• s.16
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• pp.141-163
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• 2009

This paper examined the goblin characters in Japan animation. The meaning of the goblin in this paper is not a just monster. They have a spirit. This concept is based on animism in japanese mind. I attempted a chase of goblin character's making methods. My theoretical approaches lean on the concepts "inter-textuality" of Julia Kristeva and "text" of Roland Barthes. First of all, I compared some beings of the old chinese myth-geographical book with some characters of Japan animation . The making method of goblin characters is two. One is 'Hybrid', the other is 'Mutant'. And than I appled to Japanese traditional image, "Baek-kuy-ya-hang-do"(hundreds of goblins' parade). The making method of goblins is combined to a inter-textual way as hybrid or mutant.

• Geotechnical Engineering
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• v.9 no.3
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• pp.77-90
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• 1993

In the settlement analysis of shallow foundation soil properties, loads and soil strata involve many uncertainties so it is necessary to do analysis of settlement that considers the probabilistic properties of each variable. This study is performed to probabilistic analysis for settlement of shallow foundation consisted of individual footings by using Monte Carlo Method. To consider the uncertainty of variables, both the soil properties and loads are assumed to be normal distribution random variables and get settlement mean and coefficient of variation of individual footing. And the settlement of each individual footing is also assumed to be normal distribution. Settlement of each individual footing which considers the probability of soft soil pockets in soil strata follows Markov process. Then it is performed to do sensitivity analysis which is involved to excess probability of allowable criteria of maxi mum settlement and differential settlement according to varity of each variable. It is thought to be proper that the settlement analysis of shallow foundation should be analyzed considering uncertainty of variables and soil stratum conditions.

• Korean Journal of Construction Engineering and Management
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• v.11 no.6
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• pp.45-53
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• 2010

Safety management for building deconstruction works has been received extremely limited attention in the domestic construction society. Lack of systematic safety management practices and defective education system lead to the high level of fatality compared to that of advanced countries. Under the above domestic deconstruction environment, the authors intend to develope an integrated safety management guidelines that covers both mechanical and partial deconstruction works. Research outcome includes such specific educational materials as safety manual, checklists, pocket pamphlets, and e-manuals. Furthermore, to validate the applicability of the above materials, questionnaire survey and interviews were conducted. Detailed descriptions are provided for each research outcome.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.1
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• pp.7-15
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• 2008

Currently existing high-accuracy and high-speed die sets used in reciprocal press create scratches at the surface of guide posts, steel balls, and bushes due to vertical movement of balls with point-contacts between inner surface of bushes and guide posts. Consequently, accuracy of the die set and the life span of the metal mold are reduced. However, those scratches could reduce the pre-load of the steel ball. This research designed and developed a groove-type die set which improves life span of the die set by eliminating point-contacts of steel balls with guide posts. The guide post consisted of a steel-ball retainer, a steel-ball retainer stopper, a guide bush, a guide pin, a snap ring, and a spring. The steel-ball retainer has 72 holes with 8 columns of 9 holes in each column. The inner surface of the guide bush was grinded(surface roughness: $Ra\;\\;0.2{\mu}m$, accuracy: $0\;{\sim}\;-0.002mm$) after NC turning and heat treatment. Also, a line of small intermediate pocket was processed inside of the guide bush for lubrication and elimination of foreign materials. Guide grooves of steel balls were processed using a wire EDM(Electrical Discharge Machining) after heat treatment. With such a design of the guide post stated above, loads against steel balls could be dispersed greatly by the line contacts through the guide groove between the guide post and the guide bush, and the life span of the guide post could be expanded semi-permanently.

• Journal of Korean Society of Steel Construction
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• v.18 no.5
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• pp.633-642
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• 2006

Serviceability design is required to control the cracking at the joint of precast decks with longitudinal prestress in continuous composite bridges. Details of twin-girder bridges are especially complex not only due to their main reinforcements and transverse prestresses for the design of long-span concrete slabs, but also due to the shear pockets for obtaining the composite action. This paper suggests the design guidelines for the magnitude of the effective prestress and for the selection of filling materials and their requirements that would allow for the use of precast decks for twin-girder continuous composite bridges. The necessary initial prestress was also evaluated through long-term behavior analysis. From the analysis, existing design examples were revised and their effectiveness was estimated. When a filling material with a bonding strength higher than the requirement is used in the region of a high negative moment, a uniform configuration of the longitudinal prestressing steels along thewhole span length of continuous composite bridges can be achieved, which would result in the simplification of the details and the reduction of the construction costs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.202-208
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• 2016

In this study, the defect in connection with a C-tray was inspected using a low-cost camera. The four test items were the device overlapping in the tray, the bending of the tray, the loaded quantity of the tray, and the device pocket leaving, an algorithm was developed for defining and detecting the above defect types. Therefore, the developed handling system could extend the application of the stack of the c-tray and provide a quantity verification inspection on the packing processing. The machine operation control program, which can ensure the optimal inspection image to match the scan speed, was developed and the control program that can process the user gui and the vision image utilizing the control was developed. Overall, a mechanical system that is practicable for obtaining an image and processing the vision data was designed.