• Journal of the Korean Society for Precision Engineering
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• v.20 no.6
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• pp.113-122
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• 2003

Topology optimization is begun with layout optimization that is attributed to Rozvany and Prager of the 1960's. They claimed that structure was transformed into truss connecting all the nodes of finite element and optimized by control of its sectional modulus. But, this method is partial topology optimization. General layout optimal design appliable to continum structure was proposed by Bendsoe and Kikuchi in 1988. Topology optimization expresses material stiffness of structure into function of arbitrary variable. If this variable is 1, material exists but if this variable is 0, material doesn't exist. Therefore, topology optimization searches the distribution function of material stiffness for structure. There are a few researchs for simple engineering problem such as topology optimization of square plane structure or truss structure. So, This study applied to topology optimization of table liner for vertical roller mill that is the largest scale in the world. After table liner decreased by 20% of original weight, the structure analysis for first optimized model was performed.

• Advances in concrete construction
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• v.5 no.6
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• pp.671-683
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• 2017

Commonly used concrete in general, consists of cement, fine aggregate, coarse aggregate and water. Natural river sand is the most commonly used material as fine aggregate in concrete. One of the important requirements of concrete is that it should be durable under certain conditions of exposure. The durability of concrete is defined as its ability to resist weathering action, chemical attack or any other process of deterioration. Durable concrete will retain its original form, quality and serviceability when exposed to its environment. Deterioration can occur in various forms such as alkali aggregate expansion, freeze-thaw expansion, salt scaling by de-icing salts, shrinkage, attack on the reinforcement due to carbonation, sulphate attack on exposure to ground water, sea water attack and corrosion caused by salts. Addition of admixtures may control these effects. In this paper, an attempt has been made to replace part of fine aggregate by tailing material and part of cement by fly ash to improve the durability of concrete. The various durability tests performed were chemical attack tests such as sulphate attack, chloride attack and acid attack test and water absorption test. The concrete blend with 35% Tailing Material (TM) in place of river sand and 20% Fly Ash (FA) in place of OPC, has exhibited higher durability characteristics.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1994.03a
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• pp.175-182
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• 1994

Effect of some process variables including area reduction, stroke advance, materials on the extrusion load, plastic flow and height ratio of upper to lower extruded parts in the cup-cup axisymmetric extrusion were experimentally investigated and analyzed. Deformed pattern is visualized by grid-marking technique using half-cut billets splitted. The influence of using split specimen and original specimen on the extrusion load and height ratio is examined by experiment.

• Journal of the Korean Operations Research and Management Science Society
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• v.6 no.1
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• pp.25-32
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• 1981

The optimum design problem of a proposed oil pipeline network has been formulated as a zero-one programming model to determine the optimum sizes of pipe and pump which minimize the sum of material costs and operating costs during the 20 years of life span. Applying to a real situation, the problem constitutes an assignment type zero-one programming with 372 zero-one variables and 13 constraints. A heuristic algorithm has been developed based on the modified Petersen algorithm utilizing the special form of the activity matrix. The results showed impressive cost savings of 37 percent of the total cost from the original proposal.

• Explosives and Blasting
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• v.10 no.2
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• pp.3-7
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• 1992

Concerning to Taeku city subway construction project(1-4 site), the original design was adapted NATM Tunnel method to the 8 meter thickness of overburden. Surveyor checked sity and design material and finally decided to change into Open Cut method because overburden is not only below 1 1/2 times thickness of comparate Tunnel width but there is no traffic conjunction in job site.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.187-188
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• 2017

Domestic industrial disasters are decreasing, but construction industrial disasters are increasing every year. So this study draw a conclusions from the major types of safety accidents based on disaster intensity analysis to solve the problems caused by increasing construction industry disasters. Also figure out a risk about original cause material to establish management directions which is significant manage things.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.2 s.179
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• pp.129-137
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• 2006

Polymer micro-fluidic devices were fabricated with laser processes. A UV laser and a femto laser were used to machine polymer micro-fluidic structures directly. This laser direct machining process suits the need of rapid prototyping, as in many applications changes from the original design are often required. As examples, two polymer micro-systems were developed: a micro-check valve and a micro diffuser pump. The micro fluidic devices can be applied for many applications such as clinical diagnostics and drug delivery. Advantages and disadvantages using polymers as a material for micro-fluidic applications are discussed.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.9
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• pp.1102-1107
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• 1988

We describe a volume holographic associative memory using photorefractive material and conventional planar mirror. Multiple hologram is generated with two angular multiplexed writing beams and Fourier transformed object beam in Ba Ti O3 crystal at 0.6328 um. Complete image can be recalled successfully by partial input of the original stored image without any additional thresholding and optical feedback process. It is proved that our system is useful for optical implementation of real-time associative memory and location addressable memory.

• Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.123-127
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• 2014

Parabrachiella bera (Yamaguti, 1939) is redescribed based on newly collected material from multicolorfin rainbowfish, Parajulis poecilopterus, landed at Wando fishery port on the southern coast of Korea. Although some differences were observed between the original description and the specimens examined in this study, these differences do not warrant a change in the taxonomic status of this species. Parabrachiella bera bears some resemblance to Parabrachiella incurva Shiino, 1956, but differs from it in details of the trunk and genital processes.

• Archives of design research
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• v.17 no.3
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• pp.199-208
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• 2004

From the aspect that design should respond to the necessity of various cultural bases, design is important to be grafted to Korean traditional culture. This circumstance leads this study to clarify the plan of multimedia contents development of 'paintings and original forms of shaman spirit' in Korean shamanism as one of realistic re-illumination works for Korean cultural original forms. The main study results are conduded as followings through literature reviews, internet searches and case studies. First, 'the planning process' necessary for the development of scenarios, characters and multimedia contents are suggested based on the establishment of hierarchy structure among shaman spirits which are classified into necromancer, human being, nature and life after death. Second, relating to execution of process above, it is suggested that 'the strategic. plan by business items and its genres' such as blessing fancy goods, characters for mobile or game, scenarios for game or animation, online digital exorcisms, e-cards, e-talismans and so on. Finally, as future industrialization concerns, 'the industrial development plan' is suggested which can be extended to scenario-based original businesses such as game scenarios for online or mobile and heroism fictions. The study results highlight the fact that multimedia design approach are considered for expanding the target and scope of creative material for Korean cultural original forms. Future researches, based on the results of the study, are expected to be expanded to the various designerly-thinking approaches into 'Shaman' themes and rather to be re-illuminated to the development of Korean cultural original forms as a nation's strategic standpoint.