• Title/Summary/Keyword: Spatial target

Search Result 771, Processing Time 0.042 seconds

Calibrator Survey for evolved stars using the KVN

  • Choi, Yoon Kyung;Wagner, Jan;Jung, Taehyun;Yun, Youngjoo;Cho, Se-Hyung
    • The Bulletin of The Korean Astronomical Society
    • /
    • v.41 no.1
    • /
    • pp.43.2-43.2
    • /
    • 2016
  • We present results of a calibrator search near twenty evolved stars using the Korean VLBI Network (KVN). Our evolved star targets include candidate sources for a Key Science Project (KSP) of the KVN. The KSP plans to investigate the spatial structure and dynamical effects between SiO and H2O maser regions including mass-loss process and development of asymmetry in circumstellar envelopes of evolved stars. For these purposes, we need compact and strong extragalactic sources close to the evolved stars. We carried out 5 observations in order to detect radio continuum sources that can be used for source frequency phase-referencing (SFPR) -based analysis. We observed 153 sources, out of which we detected 29 at 22 GHz and 20 at 43 GHz at signal-to-noise ratios higher than 50 at all baselines. Therefore, we successfully found target and calibrator pairs for the KVN KSP.

  • PDF

Virtual displays and virtual environments

  • Gilkey, R.H.;Isabelle, S.K.;Simpson, B.B.
    • Journal of the Ergonomics Society of Korea
    • /
    • v.16 no.2
    • /
    • pp.101-122
    • /
    • 1997
  • Our recent work on virtual environments and virtual displays is reviewed, including our efforts to establish the Virtual Environment Research, Interactive Technology, And Simulation (VERITAS) facility and our research on spatial hearing. VERITAS is a state-of -the-art multisensory facility, built around the ${CAVE}^{TM}$ technology. High-quality 3D audio is included and haptic interfaces are planned. The facility will support technical and non-technical users working in a wide variety of application areas. Our own research emphasizes the importance of auditory stimulation in virtual environments and complex display systems. Experiments on auditory-aided visual target acquistion, sensory conflict, sound localization in noise, and loxalization of speech stimuli are discussed.

  • PDF

Moving target detection by using the hierarchical spatiotemporal filters with orientation selectivity (방향성 계층적 시공간 필터에 의한 움직이는 물체의 검출)

  • 최태완;김재창;윤태훈;남기곤
    • Journal of the Korean Institute of Telematics and Electronics B
    • /
    • v.33B no.9
    • /
    • pp.135-143
    • /
    • 1996
  • In this paper, we popose a neural network that detects edges of moving objects in an image using a neural network of hierarchical spatial filter with orientation selectivity. We modify the temporal difference network by adding a self loop to each neuraon cell to reduce the problems of phantom edge detected by the neural network proposed by kwon yool et al.. The modified neural network alleviates the phantom edges of moving objects, and also can detect edges of miving objects even for the noisy input. By computer simulation with real images, the proposed neural netowrk can extract edges of different orientation efficiently and also can reduce the phantom edges of moving objects.

  • PDF

The Selection of the Scenery and Sound as the Environmental Friendly Elements (친환경 요소로서의 경관과 그에 어울리는 소리의 선택)

  • Shin, Yong-Gyu;Jeon, Ji-Hyeon;Jang, Gil-Soo;Kook, Chan
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2005.11a
    • /
    • pp.682-685
    • /
    • 2005
  • In this research, how the evaluation of the spacial image influenced by the environmental friendly elements included in the visual information, and how the selection of the sound changed depending on the characteristics of spatial image by the 40 subjects were carried out. Vast tracts of green land and the waterfront were highly preferred and impressive than the other spaces. The green music, signal with water sound and bird chirping sound were highly scored. In the frequency characteristics of the factors, the first factor was artificial sound(high at the low frequency band), the second was natural sound(uniform at all frequency band) and the third was water sound(high at the middle and high frequency band over 500Hz). This shows that the proposal of the sound which has the frequency characteristics fit to the spacial image should be selected for the soundscape of the target space.

  • PDF

Neural network algorithm for VOC gas recognition and concentration estimation at field screen using E-Nose System

  • Kim, Jeong-Do;Byun, Hyung-Gi;Ham, Yu-Kyung;Lee, Jun-Sub;Shon, Won-Ryul;Heo, Nam-Up
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.61.3-61
    • /
    • 2001
  • Field screening for pollutants has been a target of instrumental development for number of years. An electronic nose can be of substantial benefit to rapidly localize the spatial extent of a pollution or to find pollutant source. Although an electronic nose cannot separate complex composition into the whole spectrum of present volatile organic compound(VOC) in pollutants such as Gas chromatography(GC), qualitative and semi-quantitative chemical characterizations are rapidly available on site at a low cost using the optimum sensory system and pattern recognition algorithm based on neural network.

  • PDF

Visualization of chromatin higher-order structures and dynamics in live cells

  • Park, Tae Lim;Lee, YigJi;Cho, Won-Ki
    • BMB Reports
    • /
    • v.54 no.10
    • /
    • pp.489-496
    • /
    • 2021
  • Chromatin has highly organized structures in the nucleus, and these higher-order structures are proposed to regulate gene activities and cellular processes. Sequencing-based techniques, such as Hi-C, and fluorescent in situ hybridization (FISH) have revealed a spatial segregation of active and inactive compartments of chromatin, as well as the non-random positioning of chromosomes in the nucleus, respectively. However, regardless of their efficiency in capturing target genomic sites, these techniques are limited to fixed cells. Since chromatin has dynamic structures, live cell imaging techniques are highlighted for their ability to detect conformational changes in chromatin at a specific time point, or to track various arrangements of chromatin through long-term imaging. Given that the imaging approaches to study live cells are dramatically advanced, we recapitulate methods that are widely used to visualize the dynamics of higher-order chromatin structures.

State-of-the-art progress of gaseous radiochemical method for detecting of ionizing radiation

  • Lebedev, S.G.;Yants, V.E.
    • Nuclear Engineering and Technology
    • /
    • v.53 no.7
    • /
    • pp.2075-2083
    • /
    • 2021
  • The article provides a review of the research results obtained during of more than 20 years concerning using the gaseous radiochemical method (GRCM) for detecting of ionizing radiation. This method based on threshold nuclear reactions with production of radioactive noble gas which does not interact with the materials of gaseous tract. The applications of GRCM in the diagnostics of neutrinos, neutrons, charged particles, thermonuclear plasma thermometry, and the study of the structure and dynamics of astrophysical objects, position-sensitive dosimetry of neutron targets with accelerator driving, spatial distribution of the fast neutron flux density in a nuclear reactor allowing the transformation of longitudinal coordinate of neutron flux distribution into a temporal distribution of the radiochemical gas decay counting rate ("barcode" semblance) and measurement of bombarding particles spectra are described. Experimental testing of the described technologies was made on the neutron target driven with the linear proton accelerator of Institute for Nuclear Research of Russian Academy of Sciences (INR RAS).

Mouse Cre-LoxP system: general principles to determine tissue-specific roles of target genes

  • Kim, Hyeonhui;Kim, Minki;Im, Sun-Kyoung;Fang, Sungsoon
    • Laboraroty Animal Research
    • /
    • v.34 no.4
    • /
    • pp.147-159
    • /
    • 2018
  • Genetically engineered mouse models are commonly preferred for studying the human disease due to genetic and pathophysiological similarities between mice and humans. In particular, Cre-loxP system is widely used as an integral experimental tool for generating the conditional. This system has enabled researchers to investigate genes of interest in a tissue/cell (spatial control) and/or time (temporal control) specific manner. A various tissue-specific Cre-driver mouse lines have been generated to date, and new Cre lines are still being developed. This review provides a brief overview of Cre-loxP system and a few commonly used promoters for expression of tissue-specific Cre recombinase. Also, we finally introduce some available links to the Web sites that provides detailed information about Cre mouse lines including their characterization.

A Study on Two-Dimensional Variational Mode Decomposition Applied to Electrical Resistivity Tomography

  • Sanchez, Felipe Alberto Solano;Khambampati, Anil Kumar;Kim, Kyung Youn
    • Journal of IKEEE
    • /
    • v.26 no.3
    • /
    • pp.475-482
    • /
    • 2022
  • Signal pre-processing and post-processing are some areas of study around electrical resistance tomography due to the low spatial resolution of pixel-based reconstructed images. In addition, methods that improve integrity and noise reduction are candidates for application in ERT. Lately, formulations of image processing methods provide new implementations and studies to improve the response against noise. For example, compact variational mode decomposition has recently shown good performance in image decomposition and segmentation. The results from this first approach of C-VMD to ERT show an improvement due to image segmentation, providing filtering of noise in the background and location of the target.

Photoresponsive Hydrogels as Drug Delivery Systems

  • Abueva, Celine DG.;Chung, Phil-Sang;Ryu, Hyun-Seok;Park, So-Young;Woo, Seung Hoon
    • Medical Lasers
    • /
    • v.9 no.1
    • /
    • pp.6-11
    • /
    • 2020
  • Hydrogels have been developed and used in tissue engineering and regenerative medicine to deliver therapeutics to injured or diseased tissue because of their versatility and properties that can be tailored to match the natural extracellular matrix. Hydrogels can be made with a variety of physical and chemical properties combined with light responsiveness ideal for applications in different fields of medicine that require the spatiotemporal control of therapeutics. Light, as a stimulus, is relatively inexpensive, contact-free, noninvasive with high spatial resolution and temporal control, convenient and easy to use, and allows deep tissue penetration that is relatively harmless. Photoresponsive hydrogels are ideal candidates for on-demand drug delivery systems that are capable of sustained and controlled drug release, minimizing the side effects, and ensuring the activity and efficient delivery of drugs to the target tissue.