• Structural Engineering and Mechanics
• /
• v.59 no.4
• /
• pp.719-737
• /
• 2016

The present study investigated the earthquake behavior of R/C structures considering the vertical earthquake motion with the help of a comparative study. For this aim, the linear time-history analyses of a high-rise R/C structure designed according to TSC-2007 requirements were conducted including and excluding the vertical earthquake motion. Earthquake records used in the analyses were selected based on the ratio of vertical peak acceleration to horizontal peak acceleration (V/H). The frequency-domain analyses of the earthquake records were also performed to compare the dominant frequency of the records with that of the structure. Based on the results obtained from the time-history analyses under the earthquake loading with (H+V) and without the vertical earthquake motion (H), the value of the overturning moment and the top-story vertical displacement were found to relatively increase when considering the vertical earthquake motion. The base shear force was also affected by this motion; however, its increase was lower compared to the overturning moment and the top-story vertical displacement. The other two parameters, the top-story lateral displacement and the top-story rotation angle, barely changed under H and H+V loading cases. Modal damping ratios and their variations in horizontal and vertical directions were also estimated using response acceleration records. No significant change in the horizontal damping ratio was observed whereas the vertical modal damping ratio noticeably increased under H+V loading. The results obtained from this study indicate that the desired structural earthquake performance cannot be provided under H+V loading due to the excessive increase in the overturning moment, and that the vertical damping ratio should be estimated considering the vertical earthquake motion.

• Journal of IKEEE
• /
• v.23 no.4
• /
• pp.1236-1242
• /
• 2019

Recently, according to improvement of robot technology, research for mobile robot is increasing. Mobile robot having 2-wheels or 4-wheels is easy for straight driving but is difficult for direction change and rotation. So, ball robot having one contact point with base is interested by researchers. By characteristics of the one contact, ball robot is required the balancing and driving control. In this paper, smart phone application, which is usable for control by wireless communication, is proposed. The ball robot having the proposed smart phone application is designed and manufactured. Balancing and driving control by wireless communication is conducted. From the test, it is conformed that ball robot has the control performances as roll angle error is ±0.8deg, pitch angle error is ±0.7deg, x-axis position error is ±0.1m, and y-axis position error is ±0.08m for 1m driving control.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.10
• /
• pp.4903-4929
• /
• 2018

In this study, a fully automatic pose and expression invariant 3D face alignment algorithm is proposed to handle frontal and profile face images which is based on a two pass course to fine alignment strategy. The first pass of the algorithm coarsely aligns the face images to an intrinsic coordinate system (ICS) through a single 3D rotation and the second pass aligns them at fine level using a minimum nose tip-scanner distance (MNSD) approach. For facial recognition, multi-view faces are synthesized to exploit real 3D information and test the efficacy of the proposed system. Due to optimal separating hyper plane (OSH), Support Vector Machine (SVM) is employed in multi-view face verification (FV) task. In addition, a multi stage unified classifier based face identification (FI) algorithm is employed which combines results from seven base classifiers, two parallel face recognition algorithms and an exponential rank combiner, all in a hierarchical manner. The performance figures of the proposed methodology are corroborated by extensive experiments performed on four benchmark datasets: GavabDB, Bosphorus, UMB-DB and FRGC v2.0. Results show mark improvement in alignment accuracy and recognition rates. Moreover, a computational complexity analysis has been carried out for the proposed algorithm which reveals its superiority in terms of computational efficiency as well.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.9
• /
• pp.27-33
• /
• 2011

In this paper, we propose an efficient on-line handwritten digit recognition base on Convex-Concave curves feature which is extracted by a chain code sequence using Smith-Waterman alignment algorithm. The time sequential signal from mouse movement on the writing pad is described as a sequence of consecutive points on the x-y plane. So, we can create data-set which are successive and time-sequential pixel position data by preprocessing. Data preprocessed is used for Convex-Concave curves feature extraction. This feature is scale-, translation-, and rotation-invariant. The extracted specific feature is fed to a Smith-Waterman alignment algorithm, which in turn classifies it as one of the nine digits. In comparison with backpropagation neural network, Smith-Waterman alignment has the more outstanding performance.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.34 no.7
• /
• pp.1149-1161
• /
• 2010

This study identifies the dimensions of cosmetics consumption values and the differences in cosmetics brand selection through a cosmetics consumption value group and by product type. The subjects of the study were females over age 20 living in Seoul and Gyeonggi Province between January and February 2008; 427 questionnaires were used for analysis. For data analysis the SPSS 17.0 statistical program was used, and principal component analysis, factor analysis using Varimax rotation, Cronbach's ${\alpha}$ reliability testing, cluster analysis, ANOVA test, and Duncan test were conducted. The results and conclusions of this study are as follows. The dimensions of cosmetics consumption values were found to be the pleasure value, the fashion value, the function value, the brand ostentation value, and the appearance ostentation value. Five types of groups by factor were identified: the group seeking function, the group seeking fashion and brand ostentation, the group seeking pleasure, the group seeking appearance and brand ostentation, and the indifferent group. Second, The group attaching importance to functionality was more likely to select high-priced brands while the group attaching importance to brand awareness were more likely to seek foreign brands, irrespective of product type. As far as base and color cosmetics are concerned, the group attaching importance to pleasure was more likely to select low, medium, and high priced foreign brands, as well as low and medium priced domestic brands. As for body products, the group attaching importance to fashion and brand awareness tended to select low, medium, and high priced domestic brands, as well as high priced foreign brands. By simultaneously purchasing high, medium, and low priced brands, these groups display an ambivalent consumption pattern. This study identified the differing dimensions around cosmetics consumption values and cosmetic brand selection. The research findings helps cosmetic companies set product prices and contributes to cosmetic marketing strategies.

• Korean Journal of Materials Research
• /
• v.8 no.3
• /
• pp.195-199
• /
• 1998

Magnetic and Magneto-Optical properties of Co-based MnSbPt thin films prepared by R.F Sputtering were investigated. In this study, the optimum heat treatment condition was found to be $300^{\circ}C$-4hours under a $5\times10^{-6}$ Torr, but perpendicularly magnetized thin films could not be obtained. Coercive force showed maximum value of about 5000e at $250\AA$ Co thickness but the value is not enough for practical use of the thin film. Heat treated Co-based MnSbPt thin film shows 0.78 degree of Kerr rotation angle for 700nm of incident wavelength.

• Journal of Korean Society of Steel Construction
• /
• v.9 no.4 s.33
• /
• pp.601-609
• /
• 1997

Bending and vibration results for a laminated plate base on a simplified higher-order plate theory with four variables are presented. Assuming a constant in-plane rotation tensor through the thickness in Reddy's higher-order shear deformation theory it is shown that a simpler higher-order theory can be obtained with the reduction of one variable without significant loss in the accuracy. This simple higher-order shear deformation theory is then used for predicting the natural frequencies and deflection of simply-supported laminated composite plates. The results obtained for antisymmetrical laminated composite plates compare favorably with third-order and first-order shear deformation theory. The information presented should be useful to composite-structure designers, to researchers seeking to obtain better correlation between theory and experiment and to numerical analysts in checking out their programs.

• Proceedings of the KWS Conference
• /
• 2009.11a
• /
• pp.41-41
• /
• 2009

To evaluate the applicability of dissimilar joining between Mg and Al alloys in automobile manufacturing process, solid state joining processes such as magnetic pulse welding(MPW), friction stir welding(FSW) and friction spot joining(FSJ) were attempted successfully. MPW process has been concentrated mainly on round section tube to tube and tube to bar welds. AZ31 Mg alloy has been successfully welded to pure Al A1070 as well as to Al alloy A3003. While, for friction stir welding of dissimilar sheet joints, AZ31B/A6061 with the thickness of 2mm were used and a square butt joint with a good quality was obtained at the conditions of 0.8mm/sec of travel speed and tool rotation speed of 850rpm. The maximum tensile strength of 179 MPa, which was about 80 % of the Mg base metal tensile strength, has been obtained. Finally, friction spot joining was attempted to make a dissimilar lap joint between AZ31(0.8mm) and A6061(1mm), while the joint exhibited the same level of tensile shear strength as that of similar Mg joint.

• Journal of Sensor Science and Technology
• /
• v.10 no.6
• /
• pp.310-316
• /
• 2001

We have been designed and constructed an artificial odour recognition system(electronic nose system) using metal oxide type sensor array for recognizing and analyzing various odours. We proposed an unsupervised clustering method based on Euclidean distances in order for human observer to examine easily multi-dimensional data, which has been measured from an array of sensors. This is a combination of Principal Components Analysis(PCA) used as a starting point for Sammom Mapping Method(SMM). No prior assumptions are made of the classes in which odour belong, and the error due to dimensional reduction at the PCA can be minimized without the disadvantages of rotation of clusters when the order of data sets in a data base was changed in the SMM. An artificial odour recognition system with the proposed unsupervised clustering method was applied to assessment of odour differences of Volatile Organic Compounds(VOCs) and Korean whiskies respectively, and demonstrated the best performances throughout the experimental trails.

• Journal of Powder Materials
• /
• v.13 no.1 s.54
• /
• pp.62-67
• /
• 2006

Friction welding of $Al_2O_3$ particulate reinforced aluminum composites was performed and the following conclusions were drawn from the study of interfacial bonding characteristics and the relationship between experimental parameters of friction welding and interfacial bond strength. Highest bonded joint efficiency (HBJE) approaching $100\%$ was obtained from the post-brake timing, indicating that the bonding strength of the joint is close to that of the base material. For the pre-brake timing, HBJE was $65\%$. Most region of the bonded interface obtained from post-brake timing exhibited similar microstructure with the matrix or with very thin, fine-grained $Al_2O_3$ layer. This was attributed to the fact that the fine-grained $Al_2O_3$ layer forming at the bonding interface was drawn out circumferentially in this process. Joint efficiency of post-brake timing was always higher than that of pre-brake timing regardless of rotation speed employed. In order to guarantee the performance of friction welded joint similar to the efficiency of matrix, it is necessary to push out the fine-grained $Al_2O_3$ layer forming at the bonding interface circumferentially. As a result, microstructure of the bonded joint similar to that of the matrix with very thin, fine-grained $Al_2O_3$ layer can be obtained.