• Title/Summary/Keyword: Global feature

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Novel Approaches for Efficient Antifungal Drug Action

  • Lee, Heejeong;Lee, Dong Gun
    • Journal of Microbiology and Biotechnology
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    • v.28 no.11
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    • pp.1771-1781
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    • 2018
  • The emergence of multidrug-resistant microorganisms, as well as fungal infectious diseases that further threaten health, especially in immunodeficient populations, is a major global problem. The development of new antifungal agents in clinical trials is inferior to the incidence of drug resistance, and the available antifungal agents are restricted. Their mechanisms aim at certain characteristics of the fungus in order to avoid biological similarities with the host. Synthesis of the cell wall and ergosterol are mainly targeted in clinical use. The need for new approaches to antifungal therapeutic agents or development alternatives has increased. This review explores new perspectives on mechanisms to effectively combat fungal infections and effective antifungal activity. The clinical drug have a common feature that ultimately causes caspase-dependent cell death. The drugs-induced cell death pathway is associated with mitochondrial dysfunction, including mitochondrial membrane depolarization and cytochrome c release. This mechanism of action also reveals antimicrobial peptides, the primary effector molecules of innate systems, to highlight new alternatives. Furthermore, drug combination therapy is suggested as another strategy to combat fungal infection. The proposal for a new approach to antifungal agents is not only important from a basic scientific point of view, but will also assist in the selection of molecules for combination therapy.

Improving INS/GPS Integrated System Position Error using Dilution of Precision (Dilution of Precision 정보를 이용한 INS/GPS 결합시스템 위치오차 개선)

  • Kim, Hyun-seok;Baek, Seung-jun;Cho, Yun-cheol
    • Journal of Advanced Navigation Technology
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    • v.21 no.1
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    • pp.138-144
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    • 2017
  • A method for improving the integrated navigation performance in the INS/GPS navigation system by the considering that the condition that the geometric arrangement of the satellite is degraded due to limitation of the line of sight of the satellite such as geographic feature and GPS signal jamming is proposed. A variable covariance extended Kalman filter (VCEKF) that correlated to the measured covariance to the DOP of GPS is suggested. The navigation performance of integrated navigation system using EKF and VCEKF is analyzed by Monte-Carlo simulations. The result is verified that VCEKF has better estimation performance than EKF using fixed covariance on condition that DOP value is larger than the smaller value.

AN IMAGE SEGMENTATION LEVEL SET METHOD FOR BUILDING DETECTION

  • Konstantinos, Karantzalos;Demetre, Argialas
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.610-614
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    • 2006
  • In this paper the advanced method of geodesic active contours was developed for the task of building detection from aerial and satellite images. Automatic extraction of man-made structures including buildings, building blocks or roads from remote sensing data is useful for land use mapping, scene understanding, robotic navigation, image retrieval, surveillance, emergency management procedures, cadastral etc. A level set method based on a region-driven segmentation model was implemented with which building boundaries were detected, through this curve propagation technique. The essence of this approach is to optimize the position and the geometric form of the curve by measuring information along that curve, and within the regions that compose the image partition. To this end, one can consider uniform intensities inside objects and the background. Thus, given an initial position of the curve, one can determine global, region-driven functions and provide a statistical description of the inside and outside object area. The calculus of variations and a gradient descent method was used to optimize the variational functional by an iterative steady state process. Experimental results demonstrate the potential of the proposed processing scheme.

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Future Directions on the Next Generation of Digital Signage (차세대 디지털 사이니지의 발전방향)

  • Kim, Chang-Hoon;Park, Kwang-Seuk
    • Journal of the Korean Academic Society of Industrial Cluster
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    • v.4 no.1
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    • pp.51-61
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    • 2010
  • Digital Signage is outdoor media to provide each content and message through digital displays instead that posters and signs are displayed on public facilities. Recently, digital signage have been popular to deliver variety information and advertising on the rapid development of intelligent digital imaging devices based LCD, LED. Continuously digital signage demand and market are growing because digital signage feature is able to capable of interactive communication. Digital signage is expected that digital advertising market is continue rising in spite of global economic downturn at various research institutions, and it is expected to replace traditional media advertising in a new way with the coming digital signage at convergence media side.

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Apraxia of Phonation: a Case Report (발성실행증 사례연구)

  • Kwon, Mi-Seon;Na, Duk-L;Kim, Hyang-Hee;Jung, Jin-Sang
    • Speech Sciences
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    • v.12 no.2
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    • pp.101-108
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    • 2005
  • Apraxia of phonation (AOP) has often been described as a feature of apraxia of speech or of severe non-fluent type of aphasia. Pure AOP is rare and, to our knowledge, only two cases have been reported. Brain lesion sites of the reported cases were not those sites known to be responsible for apraxia of speech. This study presents a case of AOP which resulted from the secondary stroke in the left corona radiata immediately following the first stroke in the left temporoparietal lobe. A 61-year old right-handed man shwoed a global type of aphasia after the first cerebral infarction, but was able to generate spontaneously some short fragments of speech. On the day after the first infarction, he suffered from the secondary infarction, leaving him a complete loss of voluntary phonation. He did not showed any significant change in language functions. Several occurrences of involuntary phonation were observed upon laughing or crying. He was also able to cough unintentionally. A vidoe-stroboscopic examination failed to reveal any evidence of structural and functional impairment in larynx. Although this case is not of pure form of AOP, AOP appeared after the secondary stroke without significant changes of language impairment since the first stroke. Therefore, AOP may be a consequence of the brain lesion from the secondary stroke even though we cannot rule out the possibility of an additive effect of the secondary to the first stroke.

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Supervised Model for Identifying Differentially Expressed Genes in DNA Microarray Gene Expression Dataset Using Biological Pathway Information

  • Chung, Tae Su;Kim, Keewon;Kim, Ju Han
    • Genomics & Informatics
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    • v.3 no.1
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    • pp.30-34
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    • 2005
  • Microarray technology makes it possible to measure the expressions of tens of thousands of genes simultaneously under various experimental conditions. Identifying differentially expressed genes in each single experimental condition is one of the most common first steps in microarray gene expression data analysis. Reasonable choices of thresholds for determining differentially expressed genes are used for the next-stap-analysis with suitable statistical significances. We present a supervised model for identifying DEGs using pathway information based on the global connectivity structure. Pathway information can be regarded as a collection of biological knowledge, thus we are trying to determine the optimal threshold so that the consequential connectivity structure can be the most compatible with the existing pathway information. The significant feature of our model is that it uses established knowledge as a reference to determine the direction of analyzing microarray dataset. In the most of previous work, only intrinsic information in the miroarray is used for the identifying DEGs. We hope that our proposed method could contribute to construct biologically meaningful structure from microarray datasets.

Person Re-identification using Sparse Representation with a Saliency-weighted Dictionary

  • Kim, Miri;Jang, Jinbeum;Paik, Joonki
    • IEIE Transactions on Smart Processing and Computing
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    • v.6 no.4
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    • pp.262-268
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    • 2017
  • Intelligent video surveillance systems have been developed to monitor global areas and find specific target objects using a large-scale database. However, person re-identification presents some challenges, such as pose change and occlusions. To solve the problems, this paper presents an improved person re-identification method using sparse representation and saliency-based dictionary construction. The proposed method consists of three parts: i) feature description based on salient colors and textures for dictionary elements, ii) orthogonal atom selection using cosine similarity to deal with pose and viewpoint change, and iii) measurement of reconstruction error to rank the gallery corresponding a probe object. The proposed method provides good performance, since robust descriptors used as a dictionary atom are generated by weighting some salient features, and dictionary atoms are selected by reducing excessive redundancy causing low accuracy. Therefore, the proposed method can be applied in a large scale-database surveillance system to search for a specific object.

Biogeographic Feature of North Korean Ecosystem (북한 자연생태계의 생물지리적 특성)

  • Kong, Woo-Seok
    • Journal of Environmental Impact Assessment
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    • v.11 no.3
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    • pp.157-172
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    • 2002
  • This work aims to collect a biogeographic informations on the biota, alpine ecosystem, nature reserves, forest ecosystem of North Korea, and also to accumulate a basic data on the current situation and problem of the natural ecosystem of North Korea for the preparation of future cooperation and exchange between South and North Koreas. The obtained findings are as follow. First, North Korean biota contains 18,013 species, and consists of 6,710 plant species, including 3,860 species of vascular plants. Secondly, urgent investigation on the biogeographically important arctic-alpine and alpine plants and ecosystem, those are known to be endangered due to environmental change and global warming, is required. Thirdly, the conservations of diverse nature in North Korea are conducted by the introduction of various systems, such as nature preservation region, reserves for plant, animal and sea bird, and natural monuments. Fourthly, out of 9.5 million hectares of forest, one million hectares have already faced forest denudation, thus caused lots of damages for forest ecosystem. Sharp decline of North Korean forest land are due mainly to the expansion of terraced dry-field farming and deforestation. Recovery of denudated forest land should be approached by both South and North Korean sides to solve the problem of shortage of foods and restoration of natural ecosystem of North Korea.

Network-centric CAD

  • Lee, Jae-Yeol;Kim, Hyun;Lee, Joo-Haeng;Do, Nam-Chul;Kim, Hyung-Sun
    • Proceedings of the CALSEC Conference
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    • 2001.08a
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    • pp.615-624
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    • 2001
  • Internet technology opens up another domain for building future CAD/CAM environment. The environment will be global, network-centric, and spatially distributed. In this paper, we present a new approach to network-centric virtual prototyping (NetVP) in a distributed design environment. The presented approach combines the current virtual assembly modeling and analysis technique with distributed computing and communication technology fur supporting virtual prototyping activities over the network. This paper focuses on interoperability, shape representation, and geometric processing for distributed virtual prototyping. STEP standard and CORBA-based interfaces allow the bi-directional communication between the CAD model and virtual prototyping model, which makes it possible to solve the problems of interoperability, heterogeneity of platforms, and data sharing. STEP AP203 and AP214 are utilized as a means of transferring and sharing product models. In addition, Attributed Abstracted B-rep (AAB) is introduced as 3D shape abstraction for transparent and efficient transmission of 3D models and for the maintenance of naming consistency between CAD models and virtual prototyping models over the network.

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A New Stereo Matching Algorithm based on Variable Windows using Frequency Information in DWT Domain (DWT 영역에서의 주파수 정보를 활용한 가변 윈도우 기반의 스테레오 정합 알고리즘)

  • Seo, Young-Ho;Koo, Ja-Myung;Kim, Dong-Wook
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.7
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    • pp.1437-1446
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    • 2012
  • In this paper we propose a new stereo matching algorithm which is suitable for application to obtain depth information with high-speed in stereoscopic camera environment. For satisfying these condition we propose a new adaptive stereo matching technique using frequency information in discrete wavelet (DWT) domain and variable matching window. The size of the matching window is selected by analysis of the local property of the image in spatial domain and the feature and scaling factor of the matching window is selected by the frequency property in the frequency domain. For using frequency information we use local DWT and global DWT. We identified that the proposed technique has better peak noise to signal ratio (PSNR) than the fixed matching techniques with similar complexity.