• Structural Monitoring and Maintenance
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• v.7 no.3
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• pp.215-231
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• 2020

In a reinforced concrete building different shapes of column are adopted depending on the structural orientation and the architectural aspect. When there is an increase in loading due to changes in usage or revision in the design codes these columns need to be strengthened for enhanced performance during their service life. Strengthening materials such as carbon fiber and glass fiber polymer has been successfully used however, due to high cost application other alternative materials need to be explore. Galvanized steel wire mesh (GSWM) is one of the suitable materials locally available. High tensile strength, low weight, corrosion resistance, easy installation, minimum change in dimensions of the sections and cost effectives are the advantages of GSWM. Therefore, in this paper, four different shapes of column such as circular, square, rectangular and L were wrapped with different layers GSWM and jacketed with mortar. All the specimens were tested under axial compression. The objective of the study is to investigate the effectiveness of GSWM as a confining material for strengthening of column having varying shape. Test results shows that the axial strength enhanced with wrapping of GSWM jacket and a circular column presented the highest load carrying capacity and ductility as compared to the others. From the study of 22 column specimens, it is found that axial load is increased upto 20% and 19% when circular and square column are strengthened with one wrap of GSWM respectively, while a rectangular and L column required a wraps of two and three layers respectively in order to achieved the same load capacity as that of a circular column. Based on the present study, it is concluded that GSWM can be effectively used for strengthening of different shapes of concrete columns economically.

• Steel and Composite Structures
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• v.30 no.5
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• pp.483-492
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• 2019

In the current study, the influence of the initial lateral (sweep) shape and the cross-sectional twist imperfection on the lateral torsional buckling (LTB) response of doubly-symmetric steel I-beams was investigated. The material imperfection (residual stress) was not considered. For this objective, standard European IPN 300 beam with different unbraced span was numerically analyzed for three imperfection cases: (i) no sweep and no twist (perfect); (ii) three different shapes of global sweep (half-sine, full-sine and full-parabola between the end supports); and (iii) the combination of three different sweeps with initial sinusoidal twist along the beam. The first comparison was done between the results of numerical analyses (FEM) and both a theoretical solution and the code lateral torsional buckling formulations (EC3 and AISC-LRFD). These results with no imperfection effects were then separately compared with three different shapes of global sweep and the presence of initial twist in these sweep shapes. Besides, the effects of the shapes of initial global sweep and the inclusion of sinusoidal twist on the critical buckling load of the beams were investigated to unveil which parameter was considerably effective on LTB response. The most compatible outcomes for the perfect beams was obtained from the AISC-LRFD formulation; however, the EC-3 formulation estimated the $P_{cr}$ load conservatively. The high difference from the EC-3 formulation was predicted to directly originate from the initial imperfection reduction factor and high safety factor in its formulation. Due to no consideration of geometric imperfection in the AISC-LFRD code solution and the theoretical formulation, the need to develop a practical imperfection reduction factor for AISC-LRFD and theoretical formulation was underlined. Initial imperfections were obtained to be more influential on the buckling load, as the unbraced length of a beam approached to the elastic limit unbraced length ($L_r$). Mode-compatible initial imperfection shapes should be taken into account in the design and analysis stages of the I-beam to properly estimate the geometric imperfection influence on the $P_{cr}$ load. Sweep and sweep-twist imperfections led to 10% and 15% decrease in the $P_{cr}$ load, respectively, thus; well-estimated sweep and twist imperfections should considered in the LTB of doubly-symmetric steel I-beams.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.3_4
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• pp.499-508
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• 2004

The purpose of this research is to define body characteristics of middle-aged men at ages between 35 and 55 whose physical changes are very prominent, by comparing the measurement data collected from this age group. This research also classifies different body types, and provides basic data for designing slacks' original forms according to each body type. Based on factor analysis of the measured data, seven key factors are grouped. And five different body types are classified based on the cluster analysis using factor marks. Type 1 refers to those who are tall and standard. This body type is characterized by trapezoid body shape when looked from the front, and slim abdomen when looked from the side. Type 2 refers to short and a little fat body shapes, with trapezoid front and protruding hip and abdomen. Type 3 refers to tall and fat body shapes, with rectangular front, protruding abdomen, and slim hip. Type 4 refers to those who are of medium height and a little obese, with rectangular front and protruding abdomen and hip. Type 5 refers to short and obese body shapes, with rectangular front, slim abdomen, and protruding hip. 12 items are available to judge middle-aged men's low body types and the hit ratio is 90%.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.3
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• pp.61-71
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• 2000

The purpose of this article is to investigate the forms and styles of pond at private housing in terms of diachronically influencing characteristics in the Choson Dynasty. From various literatures and records, we have selected 73 cases of pond. We have analyzed the types of pond based on square type, squared type with islets, and modified types and found the following results: 1) Chronically, shapes of pond had been chanced from the three prototypes into their features of deducting side or edge, adding a triangular or trapezoid shape, and installing more islets, and replaced their figures with gradually progressive from side having a straight lined shape to a curved one. 2) As for characteristics of arranging ponds, we found three patterns of arrangement - the juxtaposition with a similar shape of pond, juxtaposition with a different shape of pond, and the juxtaposition with a pond having different topological level in the light of the relation with a stream and a pond. We can conclude the two changed patterns of ponds at private residence in Choson Dynasty that the one had been transformed shapes of pond with sides of pond, and the others had been transformed juxtaposition with either a stream or a natural stream. From this research we can find an important implications in understanding patterns and types of garden in the Choson Dynasty from exploratory approach and in the future the relationship between topographical characteristics of private residence and Confucian ideas, and shapes of pond is needed to be examined in explanatory manner.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.6
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• pp.979-994
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• 2015

The mode shapes of a segmented hull model towed in a model basin were predicted using both the Proper Orthogonal Decomposition (POD) and cross random decrement technique. The proper orthogonal decomposition, which is also known as Karhunen-Loeve decomposition, is an emerging technology as a useful signal processing technique in structural dynamics. The technique is based on the fact that the eigenvectors of a spatial coherence matrix become the mode shapes of the system under free and randomly excited forced vibration conditions. Taking advantage of the simplicity of POD, efforts have been made to reveal the mode shapes of vibrating flexible hull under random wave excitation. First, the segmented hull model of a 400 K ore carrier with 3 flexible connections was towed in a model basin under different sea states and the time histories of the vertical bending moment at three different locations were measured. The measured response time histories were processed using the proper orthogonal decomposition, eventually to obtain both the first and second vertical vibration modes of the flexible hull. A comparison of the obtained mode shapes with those obtained using the cross random decrement technique showed excellent correspondence between the two results.

• Phonetics and Speech Sciences
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• v.5 no.4
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• pp.195-200
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• 2013

This study investigates formant transition shapes of Korean front vowels produced by native speakers of Seoul Korean. Sixteen speakers (eight male and eight female speakers) produced [pVt] syllables where the vowels were [i, e, ɛ]. F1, F2, and F3 transition shapes were estimated by presenting formant values at 11 points by dividing the vowel duration into 10 different time intervals. The results indicated that the male and female speakers overall demonstrated similar formant transition shapes and measurement points arriving at the maximum and minimum formant values for the three front vowels. As for the vowels [e] and [ɛ], both male and female speakers showed similar formant values across the 11 measurement points and similar measurement points arriving at the maximum and minimum values, indicating that the two Korean vowels have been merged not only in the steady-state formant values, but also in the dynamic transition shapes.

• Earthquakes and Structures
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• v.2 no.4
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• pp.337-356
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• 2011

In this paper, cable-stayed bridges with single pylon and two equal side spans, with variations in geometry and span ranging from 120 m to 240 m have been studied. 3D models of the bridges considered in this study have been analysed using ANSYS. As the first step towards a detailed seismic analysis, free vibration response of different geometries is studied for their mode shapes and frequencies. Typical pattern of free vibration responses in different frequencies with change in geometry is observed. Further, three different seismic loading histories are chosen with various characteristics to find the structural response of different geometries under seismic loading. Effect of variation in pylon shape, cable arrangement with variation in span is found to have typical characteristics with different structural response under seismic loading. From the study, it is observed that the structural response is very much dependent on the geometry of the cable-stayed bridge and the characteristics of the seismic loading as well. Further, structural responses obtained from the study would help the design engineers to take decisions on geometric shapes of the bridges to be constructed in seismic prone zones.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.30-31
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• 2006

In a multi-action tooling system, which is usually used for the powder compaction process to fabricate the complex multilevel parts, crack formation is crucially detrimental and should be avoided. Among various process factors, tool shape is an important factor to prevent the crack formation during powder compaction process. In this work, the effects of different tool shapes were investigated through the experimental oberservation of pore distribution in real products and the finite element analysis of residual stresses. The results were interpreted based on non-uniform powder density in the compacted parts.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.56-60
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• 1996

An experimental study on the grinding temperature and Acoustic Emission(AE) signals due to the different shapes of wheel was conducted. The grinding characteristics by slotted shapes of wheel changed by width and helical angle, were compared with those by general one. Lower grinding temperature was obtained for 30$^{\circ}$ helical angle with 10mm width, Root Mean Square(RMS) values of AE signals were higher for slotted wheel rather than general one.

• Geomechanics and Engineering
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• v.36 no.1
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• pp.39-50
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• 2024

Bitumen and high-quality subangular aggregates, the two principal materials used for asphalt concrete construction, are finite and expensive materials. The general availability of crumb rubber and naturally occurring aggregates of different shapes, especially flat and elongated shapes, indicates that they are feasible alternative materials for expanding the volume of bitumen and utilizing a wider range of aggregate shapes for the development of asphalt concrete, with an associated environmental benefit. The study investigated the effect of adding up to 15% crumb rubber and aggregates sorted into different groups, i.e., rounded, elongated, flat, and their combinations, on the rheological and mechanical properties and durability of 50/70 of hot-mix asphalt pavement. The addition of crumb rubber decreased ductility and penetration but increased the softening point. For a 5.5% bitumen content, asphalt concrete briquettes consisting of 7% crumb rubber and three types of aggregate shapes, i.e., 100% rounded, a mix of 75% rounded and 25% elongated, and a mix of 75% rounded, 15% elongated and 10% flat, were associated with high Marshall stability and indirect tensile strength as well as low lateral deformation due to their high solidity and moderate angularity ratio. Also, the addition of 7% crumb rubber resulted in a significant improvement in the tensile strength ratio and rebound strain of briquettes consisting of 75% rounded and 25% elongated aggregates and those with 75% rounded, 15% elongated and 10% flat aggregates. In relation to the parameters investigated, the three groups of briquettes met some of the local (South Africa) requirements for the surface course and base course of low traffic volume roads.