• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.2
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• pp.148-154
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• 2014

Photoelasticity is a useful technique for obtaining the differences and directions of principal stresses in a model. In conventional photoelasticity, the photoelastic parameters are measured manually point by point. Identifying and measuring photoelastic data is time-consuming and requires skill. The fringe phase shifting method was recently developed and has been found to be convenient for measuring and analyzing fringe data in photo-mechanics. This paper presents an experimental study on the stress distribution along a horizontal line that passes the central point of a rhombus plate made of Photoflex (i.e., type of urethane rubber). The isoclinic fringe and/or principal stress direction is constant on this horizontal line, so a four-bucket phase shifting method can be applied. The method requires four photoelastic fringes that are obtained from a circular polariscope by rotating the analyzer at $0^{\circ}C$, $45^{\circ}C$, $90^{\circ}C$ and $135^{\circ}C$. Experimental measurements using the method were quantitatively compared with the results from FEM analysis; the results from the two methods showed comparable agreement.

• The Mathematical Education
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• v.61 no.2
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• pp.323-338
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• 2022

The purpose of this study are to analyze how well middle and high school students understand the concept definition of quadrangle and to explore the phenomenon about their concept image. A test tool was developed and 60 8th graders, 63 9^th graders and 65 10^th graders were tested, and some students who needed in-depth analysis were interviewed. The results are as follows. First, it cannot be said that understanding level of the concept definition of the quadrangle naturally improves as the grade level goes up. Particularly, it was found that the understanding of the definition of the rhombus is the lowest in all three grades compared to other quadrangle. Second, although female students understood the definition of square better than male students, the understanding level of the definition of trapezoid, parallelogram, rhombus, and rectangle did not differ by gender. Third, it was found that the students who did not understand the concept definition of the quadrangle were more and more influenced by the concept image as the grade level went up. Fourth, it showed that a tendency to be less influenced by the concept definition and more influenced by textbooks and teachers as the grades go up when students form a concept image.

• The Journal of Asian Finance, Economics and Business
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• v.1 no.2
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• pp.15-24
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• 2014

This research investigates the characteristics, principles, advantages, factors and problems of cluster development in Kazakhstan, and identifies the prerequisites, conditions and stages of organizing clusters on the framework of special economic zones. In this research, we used methods, which will allow analyzing of the organization industrial clusters in special economic zones in Kazakhstan. The author studied international experience of cluster development and the efficiency of the use of the model of the "rhombus effect" with account the specific features of interaction between the participants of the cluster, analysis of the legal framework for the formation and development of clusters. These have been identified as the more important or strategically necessary clusters in Kazakhstan: innovation-technological cluster, innovation-education cluster, innovation-petrochemical cluster, innovative-metallurgical cluster, transport and logistics cluster, textile industry cluster, tourism cluster, agro cluster, construction cluster, medical and pharmaceutical cluster. Firstly, the results suggest that the interaction of science, education, business and government in the development and implementation of innovation policy is not sufficiently structured to provide a balanced representation of the interests of the range of various innovative enterprises in Kazakhstan. Secondly, the legal basis of cluster development in Kazakhstan is determined. Need to develop mechanisms for the implementation of promising direction. Thirdly, the clusters can be formed in the existing special economic zones, allowing them to get right to the mass production of high-tech products that are developed.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.1
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• pp.159-171
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• 2018

The apron, which corresponds to an important clothing form, changed according to the taste, age, appearance and meaning of the wearer as well as from past to present. Decorative function and practical functions appear in the costumes of the East and West. Anak No. 3 tomb, Korea's 4th century Goguryeo tomb mural, was depicted in the form of a woman wearing a white apron and working in the kitchen, which is similar to that of a current kitchen, and the shape and purpose of the apron is similar to the present one. The characteristics of Korean aprons are summarized as western similarity, traditional reproducibility, and practical functionality. The U-shaped apron with the hem decoration of Goguryeo is similar to the apron of Crete with a rhombus pattern and hem decoration. Despite differences in time, it can be seen as traces of a cultural exchange across the East and the West. In addition, Korean skirts were decorated with wrinkles and a hem decoration based on rectangles. It is a reproduction of a traditional skirt and is different from a Western apron with a chest strap. In the Anak No. 3 tomb mural, women were wearing the first aprons that showed a practical functionality and not a decorative use.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.37 no.2
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• pp.33-40
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• 2000

In this study, a shape decomposition method using morphological operations is studied for decomposing the complex shape in 2-D image into its simple primitive elements. The serious drawback of conventional shape representation algorithm is that primitive elements are extracted too much to represent and to describe the shape. To solve these problems, a new shape decomposition algorithm using primitive elements that are similar to the geometrical characteristics of shape and 4 scan modes is proposed in this study. The multiple primitive elements as circle, square, and rhombus are extracted by using multiscan modes in a new algorithm. This algorithm have the characteristics that description error and number of primitive elements is reduced. Then, description efficiency is improved. The procedures is also simple and the processing time is reduced.

• Korean Journal of Ichthyology
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• v.9 no.1
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• pp.130-140
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• 1997

The osteological features of Rhodeus uyekii were examined. In this study, the detailed descriptions of cranium, vertebra and fin skeleton of Rhodeus uyekii are presented. R. uyekii had the following characteristics ; there was no fontanell in the cranium ; there was no process of supraethmoid ; the free interneural spine was large and flat ; the dorsal process of the supraoccipital was high and triangular ; the fourth infraorbital was reduced ; in the urohyal, the hypohyal attachment is bifurcated, the horizontal and vertical plate has a elongated rhombus shape with posterior edge pointed ; there was no coracoid foramen in the shoulder girdle ; there was no uroneural in the first preural centrum.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.9
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• pp.67-75
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• 1999

In this paper, a shape decomposition method using morphological operations is studied for decomposing the complex shape in 2-D image into its simple primitive elements. The serious drawback of conventional shape representation algorithm is that primitive elements are extracted too much to represent and to describe the shape. To solve these problems, a new shape decomposition algorithm using primitive elements tat are similar to the geometrical characteristics of shape and 4 scan modes is proposed in this study. The multiple primitive elements as circle, square, and rhombus are extracted by using multiscan modes in a new algorithm. This algorithm have chatacteristics that description error and number of primitive elements is reduced. Then, description efficiency is improved. The procedures is also simple and the processing time is reduced.

• Journal of Electrical Engineering and Technology
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• v.11 no.4
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• pp.974-986
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• 2016

Reversible image watermarking, a type of digital data hiding, is capable of recovering the original image and extracting the hidden message with precision. A number of reversible algorithms have been proposed to achieve a high embedding capacity and a low distortion. While numerous algorithms for the achievement of a favorable performance regarding a small embedding capacity exist, the main goal of this paper is the achievement of a more favorable performance regarding a larger embedding capacity and a lower distortion. This paper therefore proposes a reversible data hiding algorithm for which a novel piecewise 2D auto-regression (P2AR) predictor that is based on a rhombus-embedding scheme is used. In addition, a minimum description length (MDL) approach is applied to remove the outlier pixels from a training set so that the effect of a multiple linear regression can be maximized. The experiment results demonstrate that the performance of the proposed method is superior to those of previous methods.

• Bulletin of the Korean Chemical Society
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• v.19 no.1
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• pp.79-82
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• 1998

Novel coordination polymers of general form $[Co(NCS)_2(Py_2L)_2]_n\; (Py_2L=trans-1,2-bis(4-pyridyl)ethylene$ (bpee), 1; 1,2-bis(4-pyridyl)ethane (bpea), 2) have been synthesized by slow diffusion of aqueous solution of $Co(NCS)_2$ with ethanolic solution of appropriate spacer ligand, $Py_2L$, in a mole ratio of 1 : 2. X-ray analyses on both 1 and 2 have provided similar unit and infinite structures with space group Ibam. The local geometry around the cobalt(Ⅱ) atoms is an octahedral arrangement with two NCS groups in trans position (N-Co-N, 180.0° (1); 180.0°(2)) and four pyridine units in propeller fashion. Each spacer ligand connects two cobalt(Ⅱ) ions defining the edges of a $[Co(II)]_4$ rhombus. The most fascinating feature is the occurrence of perpendicular interwoven of independent square grid sheets: this is, one molecular network is perpendicularly interpenetrated through the centers of the $[Co(II)]_4$ rhombuses of another independent network with all of the cobalt(Ⅱ) atoms in a coplanar sheet. The physicochemical properties of the present unique structures were studied.

• Journal of Ecology and Environment
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• v.45 no.4
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• pp.170-173
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• 2021

Background: The Slender racer (Orientocoluber spinalis Peters, 1866) has recently been reclassified to the new genus Orientocoluber from Hierophis. Ecological knowledge of this species is limited due to its highly mobile behavior. On 17 July 2020, we captured a female O. spinalis on Oeyeon Island, Boryeong-si, Republic of Korea, and collected its feces for a diet analysis. We observed snake scales from the collected feces and subsequently determined the prey species through morphological and molecular methods. Results: We initially hypothesized that the extracted fecal sample scales belonged to H. vibakari, due to their thin keel and rhombus shape. We also amplified H. vibakari DNA from the extracted fecal sample using Illumina sequencing methods. Our morphological and molecular results suggest that O. spinalis predates H. vibakari on Oeyeon Island. Conclusion: This is the first report of O. spinalis predating another snake species, ophiophagy, and implies that H. vibakari may be a crucial prey item for O. spinalis on Oeyeon Island.