• Title/Summary/Keyword: Comparative research

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Comparative Histomorphology on Low and High Rubber Yielding Guayule Varieties of India

  • Jayabalan, Marimuthu;Rajarathinam, Kaniappanadar;Jayakumar, Muthukrishnan;Kil, Bong-Seop
    • The Korean Journal of Ecology
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    • v.24 no.6
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    • pp.381-384
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    • 2001
  • A preliminary comparative histodimensional studies, such as wood to bark ratio, total area of parenchyma cells and bast fibers, height and diameter of vascular rays, pith diameter and phenological parameters, height of the plant, perimeter of the stem, dry weight of the stem and leaves have been investigated for the low and high rubber bearing Guayule plants growing in same and different climatic regions of India. A plausible correlation is found between the percentage of rubber content and anatomical characters in the investigated varieties.

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CONVIRT: A web-based tool for transcriptional regulatory site identification using a conserved virtual chromosome

  • Ryu, Tae-Woo;Lee, Se-Joon;Hur, Cheol-Goo;Lee, Do-Heon
    • BMB Reports
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    • v.42 no.12
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    • pp.823-828
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    • 2009
  • Techniques for analyzing protein-DNA interactions on a genome-wide scale have recently established regulatory roles for distal enhancers. However, the large sizes of higher eukaryotic genomes have made identification of these elements difficult. Information regarding sequence conservation, exon annotation and repetitive regions can be used to reduce the size of the search region. However, previously developed resources are inadequate for consolidating such information. CONVIRT is a web resource for the identification of transcription factor binding sites and also features comparative genomics. Genomic information on ortholog-independent conserved regions, exons, repeats and sequences is integrated into the virtual chromosome, and statistically over-represented single or combinations of transcription factor binding sites are sought. CONVIRT provides regulatory network analysis for several organisms with long promoter regions and permits inter-species genome alignments. CONVIRT is freely available at http://biosoft.kaist.ac.kr/convirt.

Comparative Study of Sonar Image Processing for Underwater Navigation (항법 적용을 위한 수중 소나 영상 처리 요소 기법 비교 분석)

  • Shin, Young-Sik;Cho, Younggun;Lee, Yeongjun;Choi, Hyun-Taek;Kim, Ayoung
    • Journal of Ocean Engineering and Technology
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    • v.30 no.3
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    • pp.214-220
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    • 2016
  • Imaging sonars such as side-scanning sonar or forward-looking sonar are becoming fundamental sensors in the underwater robotics field. However, using sonar images for underwater perception presents many challenges. Sonar images are usually low resolution with inherent speckled noise. To overcome the limited sensor information for underwater perception, we investigated preprocessing methods for sonar images and feature detection methods for a nonlinear scale space. In this paper, we focus on a comparative analysis of (1) preprocessing for sonar images and (2) the feature detection performance in relation to the scale space composition.

Comparative Analysis of 10 MW Superconducting Wind Power Generators with Three-phase and Nine-phase Armature Windings

  • Kim, Taewon;Woo, Sang-Kyun;Sung, Hae-Jin
    • KEPCO Journal on Electric Power and Energy
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    • v.5 no.4
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    • pp.343-347
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    • 2019
  • When referring to weight, volume, and efficiency, a SuperConducting Synchronous Generator (SCSG) is definitely superior to conventional generators as a large-scale wind power generation system. The SCSG is connected to a full power converter that transmits the energy from the SCSG to the power grid. To reduce the current stress and system cost, the SCSG which has nine-phase armature windings with three converters is used. This paper deals with a comparative analysis of 10 MW superconducting wind power generators with three-phase and nine-phase armature windings. The stator windings of SCSGs are of various types. Using the finite element method, SCSGs are analyzed and compared in terms of the weight and volume of SCSGs, the total length of the superconducting wire, harmonics, torque performance, and efficiency. The analyzed results will be effectively utilized to design large-scale superconducting generators for wind power generation systems.

A Comparative Study on Collision Detection Algorithms based on Joint Torque Sensor using Machine Learning (기계학습을 이용한 Joint Torque Sensor 기반의 충돌 감지 알고리즘 비교 연구)

  • Jo, Seonghyeon;Kwon, Wookyong
    • The Journal of Korea Robotics Society
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    • v.15 no.2
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    • pp.169-176
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    • 2020
  • This paper studied the collision detection of robot manipulators for safe collaboration in human-robot interaction. Based on sensor-based collision detection, external torque is detached from subtracting robot dynamics. To detect collision using joint torque sensor data, a comparative study was conducted using data-based machine learning algorithm. Data was collected from the actual 3 degree-of-freedom (DOF) robot manipulator, and the data was labeled by threshold and handwork. Using support vector machine (SVM), decision tree and k-nearest neighbors KNN method, we derive the optimal parameters of each algorithm and compare the collision classification performance. The simulation results are analyzed for each method, and we confirmed that by an optimal collision status detection model with high prediction accuracy.

Comparative Study and Development of Computer Program on The Coefficient of Consolidation (압밀계수 산정방법의 비교연구 및 전산프로그램의 개발)

  • 장병욱;윤상묵
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.33 no.4
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    • pp.96-104
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    • 1991
  • The research effort has been focused on better calculation methods for the coefficient of consolidation under the theory of one dimensional consolidation. This research has been made available to engineers in the form of the computer program COMCv. The following conclusions can be drawn from the result of the engineering analysis, programming, and field observations. 1.Performing comparative study on six mehods(Taylor, Casagrande, Sivaram & Swamee,Su, Cour, and Scott) which can find out the coefficient of consolidation, the computer program COMCv is developed for each method. 2.Comparing the observed settlement and computed one in use of the coefficient of consolidation computed with COMCv, the result by the method of Sivaram & Swamee, Taylor, and Su is closer to the observed settlement.

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Mathematical Programming Approaches to GT Cell Formation: A Comparative Study

  • 원유경
    • Journal of the Korean Operations Research and Management Science Society
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    • v.16 no.2
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    • pp.137-137
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    • 1991
  • This paper compares and evaluates the performances of the two types of mathematical programming models for solving the machine-part cell formation problem in group technology manufacturing : indirect formulation relying on surrogate measure such as similarity coefficient and direct formulation seeking to minimize the number of exceptional elements. New indirect formulation, called the generalized p-median model. is proposed. Unlike existing p-median formulations, proposed formulation includes the classical cell formation problem in which only one process plan exsits for each part as a special case. The proposed new formulation can also deal with the cell formation problem in which alternative process plans exist for a part. The indirect formulation is compared with a new direct formulation which needs much fewer extra variables and constraints than existing direct formulations. Some significant findings from comparative experiment are discussed.

Comparative Study on Various Memristor Models

  • Jeong, Cheol-Mun;Lee, Eun-Seop;Min, Gyeong-Sik
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2011.05a
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    • pp.244.1-244.1
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    • 2011
  • Memristors have been studied for many years due to better scalability than DRAMs and FLASH memories thus they are considered now as a strong candidate for future memories. To describe the electrical behavior of memristors, various memristor models have been developed. Especially, many kinds of window function have been used to express the non-linearity of memristors which are thought to cause different voltage-current relationships in memristors. In this paper, the previous memristor models with different window functions are compared and analyzed. This comparative study can be very useful in not only understanding the diversity in memristor's electrical behaviors but also developing memristor circuits. This work was financially supported by the SRC/ERC program of MOST/KOSEF (R11-2005-048-00000-0). The CAD tools were supported by the IC Design Education Center (IDEC), Korea.

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Effects of Science Activities connected to Physical Expression on the Four-year-old Children's Creativity (신체표현 연계 과학 활동이 만 3세 유아의 창의성에 미치는 효과)

  • Moon, Hyukjun
    • Journal of Families and Better Life
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    • v.33 no.1
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    • pp.75-85
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    • 2015
  • This study aimed to examine the effects of science activities connected to physical expression on the four-year-old children's creativity. This study conducted an observation of sixty-four children of four years of age attending the kindergartens in the city of Seoul. Thirty-seven were classified in the experimental group and the remaining twenty-seven were in the comparative group. For the statistical analysis of the data collected, the t-test and the analysis of covariance(ANCOVA) were conducted. The findings of this research are as follows. The children of the experimental group who experienced science activities connected to physical expression demonstrated higher score than those of the comparative group in creativity. The result of the research indicates that science activities connected to physical expression, for children, enhances their creativity. Therefore, science activities connected to physical expression can be an effective approach for creativity of young children.

A Comparative Analysis of Energy Policies and Joint R&D Programs in Advanced Nations

  • Kim, Eun-Sun;Koo, Young-Duk;Park, Young-Seo
    • Journal of information and communication convergence engineering
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    • v.2 no.4
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    • pp.247-250
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    • 2004
  • Currently, advanced countries such as European countries and Japan invest lots of efforts to develop improvement of electric power production and supply, environmental countermeasure, and renewable energy development. Accordingly, Korea has been putting efforts to all kinds of electric related technical development based on the mid-long term plan. Further, it is necessary to increase effectiveness of R&D investment by propelling joint research activities with advanced countries for development of important technologies. Based on this background, this study tries to find thought-provoking suggestions of energy projects, programs and policies. For a comparative analysis, Japan which is similar to Korea in terms of market size and policies, and EU where joint research has been actively carried out among nations are analyzed and compared to policies and joint R&D activities of Korea.