• Structural Engineering and Mechanics
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• v.15 no.1
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• pp.135-149
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• 2003

The bubble packing method is implemented for adaptive mesh generation in two and three dimensions. Bubbles on the boundary of a three-dimensional domain are controlled independently of the interior bubbles in the domain, and a modified octree technique is employed to place initial bubbles in the three-dimensional zone. Numerical comparisons are made with other mesh generation techniques to demonstrate the effectiveness of the present bubble packing scheme for two- and three-dimensional domains. It is shown that this bubble packing method provides a high quality of mesh and affordable control of mesh density as well.

• Research in Mathematical Education
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• v.18 no.2
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• pp.129-148
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• 2014

In this study, we examined the relationships among years of teaching experience, professional rank, number of courses taken, and knowledge of algebra for teaching (KAT). 338 in-service and 376 pre-service secondary mathematics teachers in China completed a KAT questionnaire. Various statistical techniques were employed to examine these relationships. The pre-service participants teachers performed statistically significantly higher in advanced mathematics knowledge than their in-service counterparts. Among the inservice teachers, senior teachers had scored higher in school mathematics and teaching mathematics, compared with junior teachers. Yet participants' advanced mathematics knowledge decreased as their professional rank advanced or their teaching experience increased. The number of courses taken has significantly positive correlation with school mathematics knowledge and advanced mathematics knowledge. The implications of these findings for mathematics teacher education are discussed.

• International Journal of Aeronautical and Space Sciences
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• v.13 no.1
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• pp.99-105
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• 2012

Track-before-detect techniques based on dynamic programming have provided solutions for detecting targets from a sequence of images. In its application to airborne threat detection, dynamic programming solutions should take into account the distinguishable properties of objects in a collision course. This paper describes the development of a new track scoring function that accumulates scores for airborne targets in Bayesian framework. Numerical results show that the proposed scoring function has slightly better detection capabilities.

• Journal of the Optical Society of Korea
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• v.5 no.3
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• pp.83-89
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• 2001

Room temperature quasi-continuous operation is achieved near 1556 nm with threshold current as low as 2.2 mA from a 5.6-${\mu}{\textrm}{m}$ oxide-aperture vertical-cavity surface-emitting laser. Wafer fusion techniques are employed to combine the GaAs/AlGaAs mirror and the InP-based InGaAs/InGaAsP active layer. In this structure, an $Al_x/O_y$/GaAs distributed bragg reflector and intra-cavity contacts are used to reduce free carrier absorption.

• Current Optics and Photonics
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• v.2 no.5
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• pp.460-467
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• 2018

Three-dimensional (3D) refractive-index (RI) imaging and quantitative analyses of angiosperm pollen grains are presented. Using optical diffraction tomography, the 3D RI structures of individual angiosperm pollen grains were measured without using labeling or other preparation techniques. Various physical quantities including volume, surface area, exine volume, and sphericity were determined from the measured RI tomograms of pollen grains. Exine skeletons, the distinct internal structures of angiosperm pollen grains, were identified and systematically analyzed.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.04a
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• pp.50-52
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• 2009

Ontology maintenance is a time consuming and costly process which requires special skill and knowledge. It requires joint effort of both ontology engineer and domain specialist to properly maintain ontology and update knowledge in it. This is specially true for medical domain which is highly specialized domain. This paper proposes a novel approach for maintenance and update of existing ontologies in a medical domain. The proposed approach is based on modified Ontology Maturing Process which was originally developed for web domain. The proposed approach provides way to populate medical ontology with new knowledge obtained from medical documents. This is achieved through use of natural language processing techniques and highly specialized medical knowledge bases such as Unified Medical Language System.

• Journal of Sensor Science and Technology
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• v.32 no.6
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• pp.370-377
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• 2023

Soft and stretchable electronics, equipped with diverse functional devices, have recently garnered attention owing to their versatility in applications such as stretchable displays, flexible batteries, and electronic skin (e-skin). A fundamental challenge in realizing stretchable electronics lies in conferring the necessary flexibility to crucial electrical components such as electrodes and devices. However, the prevalent electronic materials, exhibit limited stretchability, presenting a significant obstacle to the advancement of soft and stretchable electronics. To overcome this challenge, various strategies rooted in geometrical engineering have been explored to enhance the adaptability of rigid materials. This study delves into the realm of geometrical engineering by, examining techniques such as serpentine patterns, kirigami-inspired designs, and island structures, with a keen focus on recent progress and future prospects.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.7
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• pp.27-33
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• 2013

In this paper, we design and analyze the performance of Coordinated Multi-Point (CoMP) techniques to the number of users for next-generation cellular systems. We perform Monte Carlo simulations with Long Term Evolution-Advanced (LTE-Advanced) and confirm the performance from the graph of the Cumulative Distribution Function (CDF). From simulation results, we show the significant performance gain when CoMP technique is used and also show better performance when we apply the various schemes additionally as scheduling and precoding.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.4
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• pp.219-230
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• 2011

The nuclear fuel cycle (NFC) analysis is a study to set a NFC policy and to promote systematic researches by analyzing technologies and deriving requirements at each stage of a fuel cycle. System analysis techniques are utilized for comparative analysis and assessment of options on a considered system. In case that NFC is taken into consideration various methods of the system analysis techniques could be applied depending on the range of an interest. This study presented NFC analysis strategies for the development of a domestic advanced NFC and analysis techniques applicable to different phases of the analysis. Strategically, NFC analysis necessitates the linkage with technology analyses, domestic and international interests, and a national energy program. In this respect, a trade-off study is readily applicable since it includes various aspects on NFC as metrics and then analyzes the considered NFC options according to the derived metrics. In this study, the trade-off study was identified as a method for NFC analysis with the derived strategies and it was expected to be used for development of an advanced NFC. A technology readiness level (TRL) method and NFC simulation codes could be utilized to obtain the required metrics and data for assessment in the trade-off study. The methodologies would guide a direction of technology development by comparing and assessing technological, economical, environmental, and other aspects on the alternatives. Consequently, they would contribute for systematic development and deployment of an appropriate advanced NFC.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.10
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• pp.4031-4040
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• 2010

The purpose of this study is to research the characteristics of masonry techniques on Roman ancient architecture. Opus so means masonry, has many types and techniques and still we use that word. Roman masonry technique appears to be very diverse kinds throughout to try and change the outcome of new technology. Depending on the use of materials the process can distinguished in three courses. First, just use only stones and bricks. Second is the use of concrete that is advanced to cement structure. Third is the use of air-dried bricks and grilled bricks. Roman masonry ranges of techniques not limited to the construction of the resulting but created a variety of architectural language. Architectural space is based on a comprehensive development of masonry techniques.