• Smart Structures and Systems
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• v.13 no.3
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• pp.375-388
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• 2014

The effectiveness of using the advanced seismic protection technology based on shape memory alloy (SMA) dampers to preserve a historical minaret is investigated. The proposed studied case, the minaret of Mansourah, is a seven century old minaret located in Tlemcen, Algeria. Its original height was of 47m, while nowadays, the monument is half destructed and its current height reaches the 40m. The proposed seismic retrofit is based on the technique that utilizes SMA wires as dampers for the upper flexible part of the minaret. The effectiveness of the proposed technique is numerically evaluated via non-linear finite element analysis using the structural software ANSYS. The effectiveness of the proposed device in mitigating the seismic hazard is demonstrated by the effective reduction in its dynamic response.

• Smart Structures and Systems
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• v.4 no.2
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• pp.153-169
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• 2008

The use of pre-tensioned shape memory alloy (SMA) wires to retrofit historic masonry structures is investigated. A small wall, serving as a prototype masonry specimen, is constructed to undergo a series of shaking-table tests. It is first studied in its original state, and its dynamic characteristics (in terms of modal frequencies) are extracted from the recorded signals. The results are then compared with those obtained when an increasing number of couples of pre-stressed SMA wires are introduced in the specimen to link the bricks together. A three-dimensional finite element model of the specimen is developed and calibrated according to the modal parameters identified from each experimental test (with and without SMA wires). The calibration process is conducted by enhancing the masonry mechanical behaviour. The results and the effectiveness of the approach are presented.

• Journal of Industrial Technology
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• v.35
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• pp.55-58
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• 2015

Natural shifting of rivers has been disturbed by anthropological activities. Urbanization in Kathmandu has been encroached the natural floodplain of Bagmati and currently channeled by training walls. The study compares the change in shape of Dhobikhola, a small tributary using 1966 and 2014 satellite images. It has been found that the original shape is heavily changed over time at the beginning and end section of river under study. The river width is now fixed by training walls and roads along the banks. Using multiple data sets like satellite images and GIS analysis, these shifts can be easily detected to plan for management and restoration of physical and ecological behaviors of rivers.

• International Journal of Contents
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• v.5 no.4
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• pp.1-6
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• 2009

In this paper, we propose a mesh smoothing method for mesh models with noise. The proposed method enables not only the removal of noise from the vertexes but the preservation and smoothing of shape recognized as edges and comers. The magnitude ratio of 2D area and 3D volume in mesh data is adopted for the smoothing of noise. Comparing with previous smoothing methods, this method does not need many iteration of the smoothing process and could preserve the shape of original model. Experimental results demonstrate improved performance of the proposed approach in 3D mesh smoothing.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.2
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• pp.149-161
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• 1997

Masked intake ports of a DOHC gasoline engine were divised and the shape was optimized to maximize the swirling and tumbling motions in the cylinder. Performances of the ports, swirling number, tumbling number and discharge coefficient were measured by Ricardo's rig test. By combination of the angle and height of the protrusions in the intake ports wall, swirling and tumbling strength can be controlled and the port shape can be optimized to increase the swirling number 13 times and tumbling number 2 times larger than those of an original port of DOHC engine with the expense of 3% decrease of discharge coefficient.

• Proceedings of the IEEK Conference
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• 2002.06d
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• pp.145-148
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• 2002

A study on image searching and management techniques is actively developed by user requirements for multimedia information that are existing as images, audios, texts data from various information processing devices. We had been studied an automatical shape region segmentation method using color. distribution and edge characteristics of moving images for. contents-base description. The Proposed method uses a color information quantized on human visual system and extracts overlapped regions to be matched by using edge characteristics of the image frame. The performance of the proposed method is represented by similarity for comparison to a segmented image and original image.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.1
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• pp.59-64
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• 1997

By using a selective learnable self-organizing feature map(SOFM) a more practical and generalized mehtod is proposed in which the effective nonlinear shape restoration is possible regardless of the existence of the distortion modelss. Nonlinear mapping relation is extracted from the distorted imate by using the proposed selective learning SOFGM which has the special property of effectively creating spatially organized internal representations and nonlinear relations of various input signals. For the exact extraction of the mapping relations between the distorted image and the original one, we define a disparity index as a proximal nmeasure of the present state to the final idealy trained state of the SOFM, and we used this index to adjust the training of the mapping relations form the weights of the SOFM. Simulations are conducted on various kinds of distorted images with or without distortion models, and the results show that the proposed method is very efficeint very efficient and practical in nonlinear shape restorations.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.7
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• pp.55-61
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• 2014

This paper presents a method to reduce the stray loss of core Tie-Plate of distribution power transformer. The method combines a 3-dimensional FEM with PSO(Particle Swarm Optimization) algorithm to determine the shape of the Tie-Plate that minimizes eddy current and flux-leakage losses. To verify the method a 24MVA distribution(cast-resin) transformer was simulated using one objective function and two design variables with some constraints. The final optimized Tie-Plate has nine($3{\times}3$) slots of 10mm width, 15mm thickness and 25mm distance. After four iterations, the Tie-Plate loss was reduced to about 21 % of the original.

• Korean Journal of Oriental Medicine
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• v.12 no.1
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• pp.39-48
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• 2006

The Following is a list of specific external and internal morphology of Rheum palmatum L. and R. undulatum L. in Rhei Rhizoma. 1. For the original plants of Rhei Rhizoma in the literatures. 18 plants are reported. 2. The external characteristics of original plant : R. palmatum has a large palmate leaf, its petiole of radical leaf has a simple bristle and its flower is purple and pink color. Whereas R. undulatum has a medium ovate leaf, its petiole of radical leaf is purphish, its stem leaf surrounds a half of stem and its flower is yellowish white color. 3. The character of herbal states : a. diameter and size-- R. palmaum is bigger and heavier than R. undulatum. b. in section--R. palmatum is dark brown color, R. undulatum is bright brown color Fibrovascular bundle is arranged in circle shape in R. patmatum. R. undulatum shows a distingushed wheel shape. 4. The internal characteristics : R. palmatum has a large intercellular space of cork layer, its cambium is clear and a xylem medullary ray is comparatively tight, Whereas R. undulatum has a tight intercettular space of cork layer., its cambium is a few clear and xylem medullary ray is verty tight. As these results, additional study is required to distinguish herbs and their effect among many kinds of same genus-degree of relatedness.

• The Korea Journal of Herbology
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• v.32 no.2
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• pp.33-40
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• 2017

Objectives : This study is aimed at establishing the discriminative criteria for Adenophorae Radix (AT; Sasam), Codonopsis Lanceolatae Radix (CL; Yangyu) and Adenophorae Remotiflori Radix (AR; Jeni). Because of confusable publications and the similitude of herb shape, CL and AR have been used as AT in the markets. Methods : We firstly discriminated and confirmed AT, CL and AR through observing the external morphology of original plants. Then, external-internal morphological features of the medicinal herbs were studied. A stereoscope was used to determine macroscopic features of dried herbal medicines and a microscope was conducted to examine internal features with the samples, which were embedded in paraffin and stained. Results : 1. The original plant of CL was discriminated with the stem shape in comparison with others. AT and AR were classified by the leaf position of original plant. 2. In the macroscopic morphological study of medicinal herbs, CL had lumps, which seem like a wart. Also, AT and AR were different in the density of cross section. 3. In the microscopic morphological study of the medicinal herbs, the phloem, fissures and the arrangement of xylem were selected as discriminative criteria for 3 kinds of herbs. With these contents, we suggested the identification keys, including further details. Conclusions : These results, especially identification keys, will be helpful to distinguish 3 kinds of herbs, referred to as a 'Sasam'. Moreover, macroscopic and microscopic methods used in this article would be applicable tools for the discrimination of other herbs.