• Title/Summary/Keyword: spatial problem

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The Process of Small Town Development in Rural China (중국 농촌 소성진 개발 과정의 특성 - 온주시 용항진의 사례를 중심으로 -)

  • 문순철
    • Journal of Korean Society of Rural Planning
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    • v.4 no.2
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    • pp.58-69
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    • 1998
  • This paper is to describe the characteristics of the Small Towns development in Rural China. The policies to develop Small Towns have been induced for solving the problem raised during the rural reform. The changes and adaptations of rural reform processes are integrated in Small Towns. The characteristics in the process of development of Ronggang, a small town, are as follows. First, it was the fund raised by rural inhabitants that was used for construction and development of the small town, Second, by implementing the policies of selective migration, the inhabitants of the small town have been differentiated from those of rural region. Third, the activities of commerce and industry of Ronggang have progressed to joint-stock system. Fourth, Having the spatial characteristics of self- development, the small town has grown and is expected to grow higher hierarchy of settlement system.

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Neutron and gamma-ray energy reconstruction for characterization of special nuclear material

  • Clarke, Shaun D.;Hamel, Michael C.;Di fulvio, Angela;Pozzi, Sara A.
    • Nuclear Engineering and Technology
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    • v.49 no.6
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    • pp.1354-1357
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    • 2017
  • Characterization of special nuclear material may be performed using energy spectroscopy of either the neutron or gamma-ray emissions from the sample. Gamma-ray spectroscopy can be performed relatively easily using high-resolution semiconductors such as high-purity germanium. Neutron spectroscopy, by contrast, is a complex inverse problem. Here, results are presented for $^{252}Cf$ and PuBe energy spectra unfolded using a single EJ309 organic scintillator; excellent agreement is observed with the reference spectra. Neutron energy spectroscopy is also possible using a two-plane detector array, whereby time-of-flight kinematics can be used. With this system, energy spectra can also be obtained as a function of position. Spatial-dependent energy spectra are presented for neutron and gamma-ray sources that are in excellent agreement with expectations.

Uniform field emission on ink-jet printed CNT emitters through oxygen trimming

  • Song, Dae-Hun;Yun, Ho-Gyu;Han, Jong-Hun;Kim, Seong-Hyeon;Lee, Gyeong-Il;Lee, Cheol-Seung;Lee, Nae-Seong;Lee, Han-Seong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.450-450
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    • 2010
  • Recently, field emission emitters made by carbon nanotubes(CNTs) and ink-jet method have been extensively studied due to their low cost, little limitation of size and a high resolution. When CNT emitters are operated, a few highly protruded ones generate most of the emission currents that cause spatial nonuniformity. In this study, we applied selective oxidation to solve this problem on ink-jet printed CNT emitters. Consequently, O2 exposures to field emitting CNT arrays give rise to a permanent damage selectively on the highly emitting CNTs. In spite of turn-on field increase, emission images was showed remarkably uniform after oxygen trimming.

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A Practical Use of Geoboard in an Elementary School Class (초등학교 수학 수업에서 기하판의 활용)

  • 최창우
    • Education of Primary School Mathematics
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    • v.6 no.1
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    • pp.1-10
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    • 2002
  • The objectives of the current study are on the practical use of geoboard in an elementary school class. To do this, we first investigate how come geoboard is significant in a practical use. Second, we present an example of practical use of geoboard connecting with the analysis of the 7th curriculum. Third, we investigate the results of geoboard which is applied to elementary school class. The results of this research are as follows: First, the instruction of using geoboard can give an interest and curiosity to all students. Second, right triangle, rectangle, square and so on can be easily constructed because geoboard is linked by dots. Third, by constructing figures on geoboard and comparing figures which is made by themselves, students could better understand the concept of figures rather than the explanation of teacher. fourth, students can be improved the ability of problem solving and spatial sense by providing experience for exploration. Fifth, students need not to have anxiety for error because geoband is used and so can be corrected easily.

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Nonequilibrium Heat Transfer Characteristics During Ultrafast Pulse Laser Heating of a Silicon Microstructure

  • Lee Seong Hyuk
    • Journal of Mechanical Science and Technology
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    • v.19 no.6
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    • pp.1378-1389
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    • 2005
  • This work provides the fundamental knowledge of energy transport characteristics during very short-pulse laser heating of semiconductors from a microscopic viewpoint. Based on the self-consistent hydrodynamic equations, in-situ interactions between carriers, optical phonons, and acoustic phonons are simulated to figure out energy transport mechanism during ultrafast pulse laser heating of a silicon substrate through the detailed information on the time and spatial evolutions of each temperature for carriers, longitudinal optical (LO) phonons, acoustic phonons. It is found that nonequilibrium between LO phonons and acoustic phonons should be considered for ultrafast pulse laser heating problem, two-peak structures become apparently present for the subpicosecond pulses because of the Auger heating. A substantial increase in carrier temperature is observed for lasers with a few picosecond pulse duration, whereas the temperature rise of acoustic and phonon temperatures is relatively small with decreasing laser pulse widths. A slight lagging behavior is observed due to the differences in relaxation times and heat capacities between two different phonons. Moreover, the laser fluence has a significant effect on the decaying rate of the Auger recombination.

Extraction of Some Transportation Reference Planning Indices using High-Resolution Remotely Sensed Imagery

  • Lee, Ki-Won
    • Korean Journal of Remote Sensing
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    • v.18 no.5
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    • pp.263-271
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    • 2002
  • Recently, spatial information technologies using remotely sensed imagery and functionality of GIS (Geographic Information Systems) have been widely utilized to various types of transportation-related applications. In this study, extraction programs of some practical indices, to be effectively used in transportation reference planning problem, were designed and implemented as prototyped extensions in GIS development environment: traffic flow estimation (TFL/TFB), urban rural index (URI), and accessibility index (AI). In TFL/TFB, user can obtain quantitative results on traffic flow estimation at link/block using high-resolution satellite imagery. Whereas, URI extension provides urban-rural characteristics related to road system, being considered one of important factors in transportation planning. Lastly, AI extension helps to obtain accessibility index between nodes of road segments and surrounding district areas touched or intersected with the road network system, and it also provides useful information for transportation planning problems. This approach is regarded as one of RS-T (Remote Sensing in Transportation), and it is expected to expand as new application of remotely sensed imagery.

Nonlinear analysis of reinforced concrete beam elements subject to cyclical combined actions of torsion, biaxial flexure and axial forces

  • Cocchi, Gian Michele;Tiriaca, Paolo
    • Structural Engineering and Mechanics
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    • v.17 no.6
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    • pp.829-862
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    • 2004
  • This paper presents a method for the nonlinear analysis of beam elements subjected to the cyclical combined actions of torsion, biaxial flexure and axial forces based on an extension of the disturbed compression field (DSFM). The theoretical model is based on a hybrid formulation between the full rotation of the cracks model and the fixed direction of the cracking model. The described formulation, which treats cracked concrete as an orthotropic material, includes a new approach for the evaluation of the re-orientation of both the compression field and the deformation field by removing the restriction of their coincidence. A new equation of congruence permits evaluating the deformation of the middle line. The problem consists in the solution of coupled nonlinear simultaneous equations expressing equilibrium, congruence and the constitutive laws. The proposed method makes it possible to determine the deformations of the beam element according to the external stresses applied.

Face Recognition Research Based on Multi-Layers Residual Unit CNN Model

  • Zhang, Ruyang;Lee, Eung-Joo
    • Journal of Korea Multimedia Society
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    • v.25 no.11
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    • pp.1582-1590
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    • 2022
  • Due to the situation of the widespread of the coronavirus, which causes the problem of lack of face image data occluded by masks at recent time, in order to solve the related problems, this paper proposes a method to generate face images with masks using a combination of generative adversarial networks and spatial transformation networks based on CNN model. The system we proposed in this paper is based on the GAN, combined with multi-scale convolution kernels to extract features at different details of the human face images, and used Wasserstein divergence as the measure of the distance between real samples and synthetic samples in order to optimize Generator performance. Experiments show that the proposed method can effectively put masks on face images with high efficiency and fast reaction time and the synthesized human face images are pretty natural and real.

The Analysis of Geospatial Efficiency of Goheung-Gun Aquaculture Type Ochon-Gye Using Bootstrap-DEA (고흥군 양식어업형 어촌계의 입지에 따른 어업효율성 분석에 관한 연구)

  • Kim, Jong-Cheon;Lee, Chang-Soo
    • The Journal of Fisheries Business Administration
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    • v.52 no.1
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    • pp.23-46
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    • 2021
  • The purpose of this study is to understand the production efficiency of individual fishing communities and provide directions for improvement. The subject of the study is aquaculture type Ochon-Gye in Goheung-gun. The analysis method used bootstrap-DEA to overcome the statistical reliability problem of the traditional DEA analysis technique. In addition, data mining-GIS was applied to identify the spatial productivity of fishing communities. The values of technology efficiency, pure technology efficiency, and scale efficiency were estimated for 32 aquaculture-type fishing villages. Then, using the benchmarking reference set and weights, the projection was presented through adjustment of the input factor excess, and furthermore, the confidence interval of the efficiency values considering statistical significance was estimated using bootstrap.

Machine Learning-based Screening Algorithm for Energy Storage System Using Retired Lithium-ion Batteries (에너지 저장 시스템 적용을 위한 머신러닝 기반의 폐배터리 스크리닝 알고리즘)

  • Han, Eui-Seong;Lim, Je-Yeong;Lee, Hyeon-Ho;Kim, Dong-Hwan;Noh, Tae-Won;Lee, Byoung-Kuk
    • The Transactions of the Korean Institute of Power Electronics
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    • v.27 no.3
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    • pp.265-274
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    • 2022
  • This paper proposes a machine learning-based screening algorithm to build the retired battery pack of the energy storage system. The proposed algorithm creates the dataset of various performance parameters of the retired battery, and this dataset is preprocessed through a principal component analysis to reduce the overfitting problem. The retried batteries with a large deviation are excluded in the dataset through a density-based spatial clustering of applications with noise, and the K-means clustering method is formulated to select the group of the retired batteries to satisfy the deviation requirement conditions. The performance of the proposed algorithm is verified based on NASA and Oxford datasets.