• Title/Summary/Keyword: Global/local analysis

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A Study on Performance Analysis of Optimization Techniques for Efficient OTC(Over-The-Cell) Channel Router (효과적인 OTC채널 라우터의 구현을 위한 최적화 기법의 성능 분석에 관한 연구)

  • Jang, Seung-Kew;Park, Jae-Heung;Chang, Hoon
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.37 no.5
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    • pp.77-87
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    • 2000
  • In this paper, we propose a Over-The-Cell channel routing algorithm for the advanced three-layer process. The proposed algorithm makes the channel routing problem to simplified one and makes use of simulated annealing technique to achieve the global optimal solution. And, a new method to remove the cyclic vertical constraints which are known to be the hardest element in the channel routing problem is proposed, and a way to detect the local minimal solution and escape from it successfully is presented. Futhermore, genetic algorithm based channel router is implemented and comparison is performed with the simulated annealing based one. All algorithms are written in C++ and GUI is made using Motif under Linux environment.

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A Study on Simple Calculation Method of Survival Time for Damaged Naval Ship Due to the Explosion (폭발에 의해 손상된 함정의 생존시간 간이계산법 연구)

  • Kim, Jae-Hyun;Park, Myung-Kyu
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.10 no.4
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    • pp.211-217
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    • 2007
  • Due to advanced new weapons and changes in the combat environment, survivability improvement methods for naval ship design have continuously evolved. Surface naval ships are easily detected by the enemy and, moreover, there are many attack weapons that may be used against surface naval ships. Therefore, it is important for modem naval ships, especially combat naval ships, to ensure survivability. In order to design a naval ship considering survivability, the designers are required to establish reasonable attack scenarios. An explosion may induce local damage as well as global collapse of the ship. Therefore, possible damage conditions should be realistically estimated at the design stage. In this study, an ALE technique was used to simulate the explosion analysis, and the survival capability of damaged naval ships was investigated. Especially, the author have establish the simple method of estimation of survival time for damaged naval ships.

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Multi-temporal Analysis of Deforestation in Pyeongyang and Hyesan, North Korea

  • Lee, Sunmin;Park, Sung-Hwan;Jung, Hyung-Sup
    • Korean Journal of Remote Sensing
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    • v.32 no.1
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    • pp.1-11
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    • 2016
  • Since forest is an important part of ecological system, the deforestation is one of global substantive issues. It is generally accepted that the climate change is related to the deforestation. The issue is worse in developing countries because the forest is one of important natural resources. In the case of North Korea, the deforestation is on the rise from forest reclamation for firewood collection and food production. Moreover, a secondary effect from flood intensifies the damage. Also, the political situation in North Korea presents difficulty to have in-situ measurements. It means that the accurate information of North Korea is nearly impossible to obtain. Thus, assessing the current situation of the forest in North Korea by indirect method is required. The objective of this study is to monitor the forest status of North Korea using multitemporal Landsat images, from 1980s to 2010s. Since the deforestation in North Korea is caused by local residents, we selected two study areas of high population density: Pyeongyang and Hyesan. In North Korea, most of clean Landsat images are acquired in fall season. The fall images have an advantage that we can easily distinguish agriculture areas from forest areas, also have an disadvantage that the forests cannot be easily identified because some of trees have turned red. To identify the forests exactly, we proposed a modified Normalized Difference Vegetation Index (mNDVI) value. The deforestation in Pyeongyang and Hyesan was analyzed by using mNDVI. The dimension of forest has decreased approximately 36% in Pyeongyang for 27 years and approximately 25% in Hyesan for 16 years. The results show that the forest areas in Pyeongyang and Hyesan have been steadily reduced.

Biodistribution and PET imaging of [18F]FMISO in mousecolon cancer xenografted mice

  • Seelam, Sudhakara Reddy;Lee, Ji Youn;Kim, Young Joo;Lee, Yun-Sang;Jeong, Jae Min
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.1 no.2
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    • pp.137-144
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    • 2015
  • Hypoxia is an important adverse prognostic factor for tumor progression and is a major cause of failure of radiation therapy. In case of short-term hypoxia, the metabolism can recover to normal, but if hypoxia persists, it causes irreversible cell damage and finally leads to death. So a hypoxia marker would be very useful in oncology. In particular, 2-nitroimidazole can be reduced to form a reactive chemical species, which can bind irreversibly to cell components in the absence of sufficient oxygen, thus, the development of radiolabeled nitroimidazole derivatives for the imaging of hypoxia remains an active field of research to improve cancer therapy result. 2-nitroimidazole based hypoxia marker, [$^{18}F$]FMISO holds promise for the evaluation of tumor hypoxia by Positron emission tomography (PET), at both global and local levels. In the present study, [$^{18}F$]FMISO was synthesized using an automatic synthesis module with high radiochemical purity (>99%) in 60 min. Immunohistochemical analysis using pimonidazole confirmed the presence of hypoxia in xenografted CT-26 tumor tissue. A biodistribution study in CT-26 xenografted mice showed that the increased tumor-to-muscle ratio and tumor-to-blood ratios from 10 to 120 min post-injection. In the PET study, [$^{18}F$]FMISO also showed increased tumor-to-muscle ratios from 10 to 120 min post-injection. In conclusion, this study demonstrates the feasibility and utility of [$^{18}F$]FMISO for imaging hypoxiain mouse colon cancer model using small animal PET.

Binarization and Stroke Reconstruction of Low Quality Character Image for Effective Character Recognition (효과적인 문자 인식을 위한 저 품질 문자 영상의 이진화 및 획 재구성 방법)

  • Kim, Do-Hyeon;Cha, Eui-Young
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.3
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    • pp.608-618
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    • 2007
  • Image binarization is an important preprocessing to identify the object of interest by dividing pixels into the background and object. We proposes efficient binarization method and a stroke reconstruction method of the low quality character image for an effective character recognition. First, the character image is binarized by using the both advantages of local and global thresholding method and then the noise elimination around the character stroke and the hole filling on the stoke by the analysis of the binarized stroke image are performed to enhance the quality of the character stroke. Proposed binarization algorithm for character image achieved an efficiency of both processing speed and performance by the adaptive threshold selection. Moreover, We could get a high qualify binary image by a stroke reconstruction of the step-by-step denoising process.

The Fashion Product Purchase and Fashion Consciousness of Malaysian Muslim Women (말레이시아 무슬림 여성의 패션제품 구매와 패션의식)

  • Jang, Seonu;Park, Hyewon
    • Journal of Fashion Business
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    • v.25 no.2
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    • pp.63-79
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    • 2021
  • In order to expand the overseas market of the Korean fashion industry, it is necessary to investigate the fashion-related purchases and fashion consciousness of Muslim women, who are increasingly attracting attention as global fashion consumers. Therefore a survey was conducted to identify the fashion design preferences and fashion consciousness of Malaysian Muslim women. A total of 245 responses were collected and analyzed. The survey included questions on demographic characteristics, fashion product purchases, design preferences and environmental awareness. The data were analyzed through frequency, average and standard deviation. The analysis showed that the majority of respondents were young Malaysian Muslim women in their 20s and 30s. They preferred a modern, Sophisticated, and sporty image, and their preference for unpatterned fabrics was high. When choosing fashion products, these women seek to both pursue fashion trends and comply with Islamic laws. When the women buy clothes, they consider practicality and design elements. The women also collected fashion trend information through SNS and the Internet, and ues this information to purchase fashion products through the Internet and shopping malls. This study was based on a practical survey of local consumers. Therefore, it is expected that the results can be used as data for fashion-related studies and to expand overseas markets to reach Muslim women in Southeast Asia.

An Empirical Study on the Export Competitiveness of Korean Automobiles in the Local Chinese Market (한국 자동차의 대중국 수출경쟁력에 관한 연구 - RCA, CAC, ESI 지수 비교를 중심으로)

  • Kim, Tae-Heon
    • International Area Studies Review
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    • v.13 no.3
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    • pp.583-611
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    • 2009
  • This study aims at analysing the export competitiveness of the six largest countries which have the highest market share in world automobile market, namely Japan, USA, China, Germany, South Korea and France for the last seven years between 2000 and 2006 in Chinese automobile market by using revealed comparative advantage index(RCA), comparative advantage index by country (CAC) and exporting similarity index(ESI). On analysis of the RCA index, it showed that the export competitiveness of Korean automobile in the world market was high following Japan and Germany, but it ranked the lowest competitiveness among the six trade competitors in Chinese automobile market. In other side, it is also made sure that the formidable competitors of Korean automobile export in global market are Germany and Japan. Therefore, South Korea needs to raise its ability to adjust to improvement of the international competitiveness in exports through close cooperation between government and automobile export enterprise and consistent monitoring about Chinese automobile industry and market.

A CPU-GPU Hybrid System of Environment Perception and 3D Terrain Reconstruction for Unmanned Ground Vehicle

  • Song, Wei;Zou, Shuanghui;Tian, Yifei;Sun, Su;Fong, Simon;Cho, Kyungeun;Qiu, Lvyang
    • Journal of Information Processing Systems
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    • v.14 no.6
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    • pp.1445-1456
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    • 2018
  • Environment perception and three-dimensional (3D) reconstruction tasks are used to provide unmanned ground vehicle (UGV) with driving awareness interfaces. The speed of obstacle segmentation and surrounding terrain reconstruction crucially influences decision making in UGVs. To increase the processing speed of environment information analysis, we develop a CPU-GPU hybrid system of automatic environment perception and 3D terrain reconstruction based on the integration of multiple sensors. The system consists of three functional modules, namely, multi-sensor data collection and pre-processing, environment perception, and 3D reconstruction. To integrate individual datasets collected from different sensors, the pre-processing function registers the sensed LiDAR (light detection and ranging) point clouds, video sequences, and motion information into a global terrain model after filtering redundant and noise data according to the redundancy removal principle. In the environment perception module, the registered discrete points are clustered into ground surface and individual objects by using a ground segmentation method and a connected component labeling algorithm. The estimated ground surface and non-ground objects indicate the terrain to be traversed and obstacles in the environment, thus creating driving awareness. The 3D reconstruction module calibrates the projection matrix between the mounted LiDAR and cameras to map the local point clouds onto the captured video images. Texture meshes and color particle models are used to reconstruct the ground surface and objects of the 3D terrain model, respectively. To accelerate the proposed system, we apply the GPU parallel computation method to implement the applied computer graphics and image processing algorithms in parallel.

College student adoption of smart learning management system - Implementing Blackboard learn - (대학생의 스마트 학습관리시스템 수용에 대한 연구 - 블랙보드 도입과 활용 -)

  • Lee, Kyu-Hye;Kim, Ji-Yeon;Seo, Hyun-Jin
    • The Research Journal of the Costume Culture
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    • v.27 no.5
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    • pp.512-523
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    • 2019
  • Contemporary University students are considered the Z generation who were born after 1995. They are more tech savvy than millennials. To target the generation, traditional class management platforms have evolved to smart LMS that is more customized and accessible for smart devices. Global level information search and collaboration can also be implemented using such smart LMS. However, switching from one LMS to another LMS requires great effort from teachers and support from staffs. This study measured the learners' perception of the system when they were exposed to a new smart-LMS. Blackboard Learn Ultra was used for 15 weeks and at the end of the semester, a questionnaire was administered to the students of these classes. Results indicated that experience with previous LMS discouraged students from adopting Blackboard Learn. Result of TAM modeling indicated that perceived usefulness, compared to perceived ease of use and attitude, was an effective aspect to bring positive acceptance of the system. A qualitative approach and network analysis were also conducted based on students' responses. Both positive and negative responses were detected. Inconvenience due to mechanical aspects was mentioned. Dissatisfaction compared to previous local LMS use was also mentioned. Mobile application and communication effectiveness were positive aspects. Revised course development and promoting how useful the system may help enhance the acceptance of the new system.

Behavior of three-tube buckling-restrained brace with circumference pre-stress in core tube

  • Li, Yang;Qu, Haiyan;Xiao, Shaowen;Wang, Peijun;You, Yang;Hu, Shuqing
    • Steel and Composite Structures
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    • v.30 no.2
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    • pp.81-96
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    • 2019
  • The behavior of a new Three-Tube Buckling-Restrained Brace (TTBRB) with circumference pre-stress (${\sigma}_{{\theta},pre}$) in core tube are investigated through a verified finite element model. The TTBRB is composed of one core tube and two restraining tubes. The core tube is in the middle to provide the axial stiffness, to carry the axial load and to dissipate the earthquake energy. The two restraining tubes are at inside and outside of the core tube, respectively, to restrain the global and local buckling of the core tube. Based on the yield criteria of fringe fiber, a design method for restraining tubes is proposed. The applicability of the proposed design equations are verified by TTBRBs with different radius-thickness ratios, with different gap widths between core tube and restraining tubs, and with different levels of ${\sigma}_{{\theta},pre}$. The outer and inner tubes will restrain the deformation of the core tube in radius direction, which causes circumference stress (${\sigma}_{\theta}$) in the core tube. Together with the ${\sigma}_{{\theta},pre}$ in the core tube that is applied through interference fit of the three tubes, the yield strength of the core tube in the axial direction is improved from 160 MPa to 235 MPa. Effects of gap width between the core tube and restraining tubes, and ${\sigma}_{{\theta},pre}$ on hysteretic behavior of TTBRBs are presented. Analysis results showed that the gap width and the ${\sigma}_{{\theta},pre}$ can significantly affect the hysteretic behavior of a TTBRB.