• Journal of the Korea Society of Computer and Information
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• v.20 no.10
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• pp.15-21
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• 2015

In this paper, we propose a stable automatic signature verification algorithm applicable to various smart devices. The proposed algorithm uses real and forgery data all together, which can improve the verification rate dramatically. As a tool for signature acquisition in a smart device, two applications, one using touch with a finger and the other using a pressure-sensing-stylus pen, are developed. The verification core is based on SVM and some modifications are made to include the characteristics of signatures. As shown in experimental results, the minimum error rate was 1.84% in the SVM based method, which can easily defeat 4.38% error rate with the previous parametric approach. Even more, 2.43% error rate was achieved with the features excluding pressure-related features, better than the previous approach including pressure-related features and only about 0.6% more error than the best result, which means that the proposed algorithm can be applied to a smart device with or without pressure-sensing-stylus pens and used for security purposes.

• ETRI Journal
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• v.46 no.4
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• pp.648-659
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• 2024

Author verification is challenging because of the diversity in writing styles. We propose an enhanced handwriting verification method that combines handcrafted and automatically extracted features. The method uses a genetic algorithm to reduce the dimensionality of the feature set. We consider offline Bangla handwriting content and evaluate the proposed method using handcrafted features with a simple logistic regression, radial basis function network, and sequential minimal optimization as well as automatically extracted features using a convolutional neural network. The handcrafted features outperform the automatically extracted ones, achieving an average verification accuracy of 94.54% for 100 writers. The handcrafted features include Radon transform, histogram of oriented gradients, local phase quantization, and local binary patterns from interwriter and intrawriter content. The genetic algorithm reduces the feature dimensionality and selects salient features using a support vector machine. The top five experimental results are obtained from the optimal feature set selected using a consensus strategy. Comparisons with other methods and features confirm the satisfactory results.

• 한국기계연구소 소보
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• s.10
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• pp.11-20
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• 1983

Photoelasticity is an experimental technique for stress and strain analysis that is particularly useful for members having complicated geometry, complicated loading conditions, or both. The principle and engineering applications of photoelastic stress analysis are briefly reviewed. Experimental stress analysis with Reflection Polariscope at KIMM Structural Mechanics Laboratory was applied to the following practices: Stress analysis of the crosshead of the structural fatigue testing machine; Experimental safety verification of domestic excavator.

• Korean Institute of Interior Design Journal
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• v.20 no.2
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• pp.30-38
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• 2011

Personal creativity could be promoted and improved through many experience, training and various prior knowledge. This researcher had proceeded several preceding studies to find effective using methods of analogy for creativity enhancement. This study, following work of preceding studies aims to verify the effects of verbal and visual analogy for creativity improvement. Effect verification had been progressed by comparing the residential design results of two groups which are classified an experimental group consisted of sophomore college students with a comparative group consisted of sophomore university students. Consequently, the experimental group that had undergone many training on verbal and visual analogy in several preceding studies is superior to the comparative group in terms of creative design rate, sketch rate with high quality. Through this result it is verified that the using methods of verbal and visual analogy is very effective on creativity enhancement in interior design process. But the limitation of this study is that there were a few populations. Nevertheless, interdisciplinary this study will be used as a practical one to suggest a model on a teaching method and a theory for creativity improvement in interior design education.

• Transactions of Materials Processing
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• v.28 no.3
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• pp.115-122
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• 2019

In this paper, finite element analysis of an automatic five-stage precision cold forging process of a yoke, a steering part of a passenger's car, is conducted with emphasis on spring back analysis at the yoke-forming stage and its experimental verification is subsequently made. An elastoplastic finite element method with MINI-element technique employed for the analysis of the entire process is explained. There is emphasis that the thin film of material formed between the punch and die in the stage may result to some errors especially in elastoplastic finite element analysis of spring back due to frequent remeshing. The numerical robustness of the spring back analysis in regards to remeshing is hence shown first through investigation into its effect on the predicted spring back. Experimental measurement of displacement due to spring back is carried out for comparison with the predicted results, and they are in a qualitative agreement with each other.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1996.10a
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• pp.96-100
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• 1996

So far the analysis and modeling of cutting process is studied commonly assumed as being linear stochastic or chaotic without experimental verification. So we verified force signals of cutting process(ball end-milling) is low-dimensional chaos by calculating Lyapunov Exponents. reconstructing attractor using time delay coordinates and calcula-ting it's fractal dimension.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.28B no.11
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• pp.904-912
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• 1991

Automatic recognition of seal imprint has been required in the oriental countries. In this paper, a hierarchical approach for seal imprint verification is presented. Global features are used for seal imprint description in the first step. In the second step, conventional and several proposed local features are used to detect useful informations such as size, distribution and relative position of stroke length from seal imprint. In the last step, seal imprints are classified into one of three categories 'accept', 'ambiguous' and reject', based on the hierarchical classification. Experimental results show good performance on classification and recognition.

• Proceedings of the KSPS conference
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• 2003.05a
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• pp.137-140
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• 2003

In this paper, we propose a robust endpoint detection algorithm for speaker verification. Proposed algorithm uses energy and cepstral distance parameters, and it replaces the detected endpoints with endpoints of voiced speech, when the estimated signal-to-noise ratio (SNR) is low. Experimental results show that proposed algorithm is superior to energy-based endpoint detection algorithm.

• The Journal of Korea Robotics Society
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• v.4 no.2
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• pp.105-111
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• 2009

In this paper, we provide experimental results and verification for obstacle avoidance algorithm 'ELA(Emergency Level Around)', which is applicable to rescue robots. ELA is a low level intelligence-based obstacle avoidance algorithm, so can be used in fast mobile robots requiringhigh speed in operation with little computational load. Constructed system for experiments consist of laptop, sensors, peripheral devices and mobile robot platform VSTR(Variable Single-tracked Robot) to realize predetermined scenarios. Finally, experiment was conducted in indoor surroundings including miscellaneous things as well as dark environment to show fitness and robustness of ELA for rescue, and it is shown that VSTR navigates endowed area well with real-time obstacle avoidance based on ELA. Therefore, it is concluded that ELA can be a candidate algorithm to increase mobility of rescue robots in real situation.

• Journal of the Korean Society of Industry Convergence
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• v.17 no.1
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• pp.15-19
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• 2014

Recently, cyclone is used to collect fine particles in various industrial precesses, but many studies are undergoing because of cyclone's low collection efficiency. Thus, we have developed water-cyclone which minimizes disadvantages of existing conventional cyclone and designed 3 different stages depending on precessing materials. Stage 1 collects particles by using principles of conventional cyclone. Stage 2 processes acid gases by extending contact time with water film through vortex movement. Stage 3 processes uncollected substances in stage 1 and 2. Hence, we evaluate water-cyclone by experimental verification.