• Structural Engineering and Mechanics
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• v.18 no.2
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• pp.211-229
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• 2004

The main purpose of this paper is the numerical analysis of the non-linear seismic response of a RC building mock-up. The mock-up is subjected to different synthetic horizontal seismic excitations. The numerical approach is based on a 3D-model involving multilayered shell elements. These elements are composed of several single-layer membranes with various eccentricities. Bending effects are included through these eccentricities. Basic equations are first written for a single membrane element with its own eccentricity and then generalised to the multilayered shell element by superposition. The multilayered shell is considered as a classical shell element : all information about non-linear constitutive relations are investigated at the local scale of each layer, whereas balance and kinematics are checked afterwards at global scale. The non-linear dynamic response of the building is computed with Newmark algorithm. The numerical dynamic results (blind simulations) are considered in the linear and non linear cases and compared with experimental results from shaking table tests. Multilayered shell elements are found to be a promising tool for predictive computations of RC structures behaviour under 3D seismic loadings. This study was part of the CAMUS International Benchmark.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.8
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• pp.3350-3365
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• 2020

A considerable literature has recently grown up on the theme of ship wireless communications. However, much of the research up to now has been descriptive in the offshore area. There has been little quantitative analysis of wireless communication in inland waterways, which has received considerable attention lately. Until now, only the effects on inland river environment are examined. What is less clear is the nature of channel change caused by the antenna movement. Here we explore the moving ship-to-fixed-ship fading characteristics at 5.9 GHz for an inland waterway in the city center of China. The ship motion trajectory is designed in order to determine the effect of changes in the antenna position. We evaluate the channel fading characteristics of inland waterway, which are highly correlated with the distance between transmitter and receiver. We demonstrate that the line-of-sight component, as well as the components from multipath with obstruction reflections, contributes largely to the mean power gap. Our findings reveal critical ship-to-ship characteristics in inland waterway, which definitely contribute to the field of ship wireless communications.

• Journal of the Korean Solar Energy Society
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• v.28 no.6
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• pp.15-23
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• 2008

The article deals with system technology of a new solar heating system which systematically combines exiting solar collector technology, auxiliary electrical water heating, floor heating system and well insulated construction method and its application of this system to apartment house heating system in the cold region, and also analyzed performance of the new system in terms of technical and economic feasibility. Results shows that energy efficiency approaches up to 50% of the energy consumption of local construction from 1980 to 1981. The implementation of "DQ technology" to floor heating system achieved from 79% to 85% of the energy-saving benefits comparing to other housing units which were supplied by the local district heating plant.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.5
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• pp.523-530
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• 2013

In this work, we study a heat transfer enhancement technology using fan-shaped small-scale fins. Fins having a thickness of 10 ${\mu}m$ move up-down by a pulsating flow. Owing to these motions, the heat transfer on a surface increases dramatically. The two-way FSI (fluid-structure interaction) method was applied for the analysis, and the analysis model was evaluated using a single fin model by comparing the experimental results. In summary, a maximum 40% increase in heat transfer capacity using a single and multiple small-scale fins was obtained in comparison with the results obtained without using fins. From this work, we believe that the proposed method can be a promising method for heat transfer enhancement in real applications.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.1055-1056
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• 2008

In this paper, we survey various Robust Object Recognition Algorithms. One of the core technologies for local feature detector is Scale Invariant Feature Transform. And we compared several algorithms with SIFT based on IPP technology. As a result, the conversion of source codes using IPP is sped up. And this will be more improved recognition speed using SIMD Instructions.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.10a
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• pp.80-93
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• 1995

Membrane Technology, which has been in use for over twenty five years, has established itself as one of the principle separation methods. With improved technology, Reverse Osmosis ("RO") has been applied to large volume water treatment facilities. UF and MF Membrane Technology has, up until recently, been applied to small scale water treatment facilities. The fouling of membrane has restricted the growth of Membrane Technology in Water Treatment. Membrane fouling compound found in water causes the loss of flux across the membrane by absorbing to membrane and plugging their pores. Various methods have been used in the reduction and prevention of membrane fouling. For RO, a conventional pre-treatment system removes the pollutants, preventing the function decline of RO membrane by keeping SDI < 4 as the standard condition of feed water. UF and MF Membrane Technology that must have pre-treatment function within itself, are required to keep its ability not to be influenced by fouling.y fouling.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.3
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• pp.122-129
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• 1997

Machining technology has emerged to the point of performing atomic-scale fabrication. In tail paper atomic-scale machining characteristics are investigated by using Molecular Statics simulation method. The cutting model used in this work simulates machining with tools such as an AFM. It is shown that built-up edge formation and cutting forces depend on tool tip geometry. Also, the material flow during cutting is shown for various cutting conditions such as depth of cut, rake angle, and edge radius of tool.

• International Journal of Concrete Structures and Materials
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• v.9 no.3
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• pp.267-281
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• 2015

Six full-scale prestressed concrete (PC) I-beams with steel fibers were tested to failure in this work. Beams were cast without any traditional transverse steel reinforcement. The main objective of the study was to determine the effects of two variables-the shear-span-to-depth ratio and steel fiber dosage, on the web-shear and flexural-shear modes of beam failure. The beams were subjected to concentrated vertical loads up to their maximum shear or moment capacity using four hydraulic actuators in load and displacement control mode. During the load tests, vertical deflections and displacements at several critical points on the web in the end zone of the beams were measured. From the load tests, it was observed that the shear capacities of the beams increased significantly due to the addition of steel fibers in concrete. Complete replacement of traditional shear reinforcement with steel fibers also increased the ductility and energy dissipation capacity of the PC I-beams.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.252-257
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• 2001

With the help of newly arrived technology such as PC clustering, molecular dynamics (MD) seems to be promising for large-scale materials simulations. A cost-effective cluster is set up using commodity PCs connected over Ethernet with fast switching devices and free software Linux. Executing MD simulations in the parallel sessions makes it possible to carry out large-scale materials simulations at acceptable computation time and costs. In this study, the MD computer code for fracture simulation is modified to comply with MPI (Message Passing Interface) specification, and runs on the PC cluster in parallel mode flawlessly. It is noted that PC clusters can provide a rather inexpensive high-performance computing environment comparing to supercomputers, if properly arranged.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2000.04a
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• pp.35-40
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• 2000

MCM technology languished troughout most of the 1990's due to high costs resulting from low yields and issues with known god die. During the last five years of the decade new developments in chip scale packages and high density, build up multi-layer printed wiring boards created new opportunities to design and produce ultra miniaturized modules using conventional surface mount manufacturing capabilities. Focus on the miniaturization of substrate based packages such as ball grid arrays (BGAs) resulted in chip scale packages (CSPs) offering many of the benefits of flip chip along with the handling, testing, manufacturing and reliability capabilities of packaged deviced. New developments in the PWB industry sought to reduce the size, weight, thickness and cost of high density interconnect (HDI) substrates. Shrinking geometries of vias and new constructions significantly increased the interconnect density available for MCM-L applications. This paper describes the most promising CSP and HDI technologies for portable products, high performance computing and dense multi-chip modules.