• Bulletin of the Korean Chemical Society
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• v.32 no.10
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• pp.3702-3706
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• 2011

The conformation of a neuropeptide, substance P (SP), in isotropic (q = 0.5) acidic bicelles was investigated using two-dimensional NMR techniques. By the nuclear Overhauser effect (NOE) cross peaks between SP and long-chain lipid molecules SP was probed to bind on the flat surface of the disc-like bicelles. Structural analysis of NMR data indicated that the helical conformation of SP extended to the C-terminal region of Leu10 as well as in the mid-region from Pro4 to Phe8. As compared with the conformations of SP bound on the sodium dodecylsulfate (SDS) or the dodecylphosphocholine (DPC) micelles with curved surfaces, the surface curvature of the membrane mimics was found to be one of the major factors inducing the biologically relevant conformation of SP. The negative surface charge of the membrane is also a key factor inducing both the binding of SP on the membrane and its biologically active structure.

• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.6
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• pp.11-19
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• 2001

A series of test on concrete-filled composite columns was preformed to evaluate structural performance under axial compression and cyclic lateral loading. It was presented that concrete-filled composite columns had high strength, high stiffness and large energy-absorption capacity on account of mutual confinement between the steel plate and filled-in concrete. A cross section analysis procedure developed to predict the moment-curvature relation of composite columns was proven to be on accurate and effective method. The ductility factor and the response modification factor were evaluated for the seismic design of concrete-filled composite columns. It was shown that concrete-filled composite columns could be used as a very efficient earthquake-resistant structural member.

• Composites Research
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• v.13 no.4
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• pp.67-74
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• 2000

The general solution of the anti-plane shear problem for the curved interfacial crack between viscoelastic foam and composites was investigated with the complex variable displacement function. Kelvin-Maxwell three parameter model is used to present viscoelasticity and the Laplace transform was applied to treat the viscoelastic characteristics of foam in the analysis. The stress intensity factor near the interfacial crack tip was predicted by considering both anisotropic and viscoelastic properties of two different materials. The results showed that the stress intensity factor increased with increasing the curvature of the curved interfacial crack and it also increased and eventually converged to a specific value with increasing time. The stress intensity factor increased with increasing the ratio of stiffness coefficients between foam and composites and the effect of fiber orientation on the stress intensity factor decreased with increasing the ratio of stiffness coefficients between foam and composites.

• Journal of the Earthquake Engineering Society of Korea
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• v.10 no.5 s.51
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• pp.85-97
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• 2006

Capacity design is to guarantee ductile failure of whole bridge system by preventing brittle failure of columns and any other structural elements until the columns develope fully enough plastic deformation capacity. This concept has been explicitly regulated in most bridge design specifications of foreign countries except the current Korea Bridge Design Specifications. In the capacity design, the transformed shear force from flexural overstrength of reinforced concrete column is used as the design lateral shear force for shear design of columns and design of footings and piles. Different calculating methods are adopted by the design specifications, since the variability of material strength and construction circumstances of the local regions should be considered. This paper proposed material overstrength factors by investigating 3,407 reinforcing bar data and 5,405 concrete compressive strength data collected in Korean construction sites. It also proposed calculating procedures for flexural overstrength of reinforced concrete columns using the material overstrength. Finally, overstrength factor was proposed as 1.5 by investigating 1,500 column section data from moment-curvature analysis using the material overstrength.

• Economic and Environmental Geology
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• v.35 no.1
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• pp.67-74
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• 2002

The purpose of this study is to determine the weights of the factors for landslide susceptibility analysis using artificial neural network. Landslide locations were identified from interpretation of aerial photographs, field survey data, and topography. The landslide-related factors such as topographic slope, topographic curvature, soil drainage, soil effective thickness, soil texture, wood age and wood diameter were extracted from the spatial database in study area, Yongin. Using these factors, the weights of neural networks were calculated by backpropagation training algorithm and were used to determine the weight of landslide factors. Therefore, by interpreting the weights after training, the weight of each landslide factor can be ranked based on its contribution to the classification. The highest weight is topographic slope that is 5.33 and topographic curvature and soil texture are 1 and 1.17, respectively. Weight determination using backprogpagation algorithms can be used for overlay analysis of GIS so the factor that have low weight can be excluded in future analysis to save computation time.

• Korean Journal of Optics and Photonics
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• v.9 no.6
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• pp.408-412
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• 1998

As the radius of curvature of curved optical waveguide gets smaller, the loss increases at the junction of linear-curved waveguide by the cross sectional mode mismatch. The concept of lateral offset has been used widely to minimize it, and simple method of maximum matching has been efficient for most cases of silica waveguide with low optical confinement and large radius of curvature. Here, we analyzed that the propagation mode characteristics of the lateral offset and propagation mode characteristics of general case with effective index method and Airy function solution. As the normalized frequency varies, mode characteristics changes near the boundary of 1/V=0.7 and the simple matching of gaussian profile might give -35% of error at most. We proposed improved method with a new correction factor to improve the mode mismatch problem of conventional methods for general cases, and showed the convenience and feasibility of this method for the calculation of the lateral offset.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.114-117
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• 2008

Curved thick plate forming in shipbuilding industry is currently performed by a thermal process, called as Line Heating by using gas flame torches. It was examined as an alternative way in this study to manufacture curved thick plates by the multi-punch die forming. Experiments and finite element analyses were conducted to evaluate the feasibility of the reconfigurable discrete die forming to the thick plates. Configuration of the multi-punch dies suitable for multi-curvature was investigated. As a result, single step forming by reconfigurable discrete die with scale factor improved formability.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.4
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• pp.38-43
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• 2011

Industrial reducer is in general use to Deck Crane. High-precision and high-efficient reducer is minimized the power-loss and energy-loss of a machine. So it contribute the price reduction and life extension. Reducer is usually using the Planetary gear reducer. Planetary gear reducer is composed the sun gear, planet gear, internal gear and casing. Industrial reducer's wear and breakage have a short-life. To solve this problem, it is using the profile-shifted-gear or tooth modification. This study was carried out the effect of addendum modification coefficient on tooth fillet bending strength to planetary reducer. Tooth fillet bending stress is calculate. And all parameter were expressed the function of addendum modification coefficient. And then stress concentration factor of tooth fillet curve was express the function of addendum modification coefficient using comparison between theory and finite element analysis.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.8
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• pp.335-343
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• 2002

A segment matching algorithm in stereo vision via the fusion of multiple features on long edge segments is proposed. One problem of the previous segment matching algorithm is the similarity among the segments caused from its short length. In the proposed algorithm, edges are composed of longer segments which are obtained by breaking the edges only at the locations with distinguished changes of the shape. Such long segments can contain extra features such as curvature ratio and length of segments which could not be included in shorter ones. Use of such additional features enhances the matching accuracy significantly To fuse multiple features for matching, weighting value determination algorithm which is computed according to the degree of the contribution of each factor is proposed. The stereo matching simulations with the proposed algorithm are done about various images and their results are included.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.527-532
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• 1997

Design strength of structural members could be determined by applying a strength reduction factor to nominal strength. At the beginning point of the transition region for the strength reduction factor, P=0.1$\sigma$$_{ck}A_g$, only sectional area and concrete strength are adopted as the variables of P=0.1$\sigma$$_{ck}A_g$. Therefore, P=0.1$\sigma$$_{ck}A_g$ is the empirically adopted which does not consider steel ratio, steel yielding stress, and steel arrangement. So, this research was perpormed the computer program for the analysis of axial force-moment-curvature relationship of reinforced concrete columns by sectional behaviour nonlinear analysis using a concrete compressive stress-strain curve, in order to investigate the ductility of reinforced concrete columns. As a result, ductility indicies of axial force, P=0.1$\sigma$$_{ck}A_g$, represented the lack of consistency of the indicies value for the various sections.