The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Discriminative measurement of strain and temperature distribution is experimentally demonstrated by optical time-domain reflectometry of Brillouin dynamic grating (BDG-OTDR) in an elliptical core two-mode fiber (e-core TMF). The acoustic waves generated by the amplified spontaneous Brillouin scattering of LP01 mode in x-polarization are used to reflect the LP11 mode in x- and y-polarizations. Distribution...
Distributed measurement of hydrostatic pressure is demonstrated based on optical time domain analysis of Brillouin dynamic grating (BDG) in polarization maintaining fibers (PMF's). Spectral shift of the BDG is analyzed as a function of hydrostatic pressure from 14.5 psi (1 bar) to 884.7 psi (61 bar) using bow-tie PMF's and photonic crystal PMF (PM-PCF) with 1 m spatial resolution. The experimental...
Transition from TBM(Time-Based Maintenance) to CBM(Condition-Based Maintenance) is required on aging estimation of power cable. To maximize the cable estimation efficiency, sequential reinforcement standards must be established in accordance with aging factor. In this paper, diagnostic on a Medium Voltage(MV) underground cables using tan δ measurement that measures dissipation factor with 0.1Hz VLF...
Brillouin dynamic grating (BDG) represents an acoustic phonon generated by stimulated Brillouin scattering (SBS) of pump waves in one polarization which plays a role of reflection grating for probe wave at different optical frequency orthogonally polarized to the pump. Since the optical frequency offset between the pump and probe waves, called BDG frequency, is determined by the birefringence of the...
Temperature dependencies of the Brillouin dynamic grating (BDG) spectra in polarization-maintaining fibers (PMF's) are rigorously investigated. PANDA fiber, Bow-tie fiber, and PM photonic crystal fiber (PM-PCF) with different parameters are tested in the temperature range of −30 to +150 °C, where the linear and nonlinear temperature dependencies are quantified for each fiber. It is observed that bare...
Paddy field extraction is a prerequisite to precision agriculture and to the monitoring of the rice condition. Many studies have been carried out for improving the mapping accuracy and retrieving the biophysical parameter, but most of these studies used the scattering characteristics of the rice crop, and little attention has been given to the topographic information provided by the single polarimetric...
Big Data is used to find new value and brings us several benefits, which we didn't know before. Various analytics has been studied in Big Data area for benefits. Moreover, to reduce analysis time and to support real-time service to user, distributed processing can be an alternative solution. Big Data also requires high performance resource for distributed analysis, for this reason, Big Data and Cloud...
The hyperspectral vegetation index (HVI) has shown promise in vegetation fields, but its relationship to the radar vegetation index (RVI) is not known in the context of various land covers. This work presents a comparative analysis of the HVI data derived from the AISA sensor and RVI values originating from the RADARSAT-2 quad-polarimetric synthetic aperture radar (SAR) data. Six types of land cover...
Nowadays, providing personalized service to customers is one of the main issues in big data services. To provide the personalized service, analyzing various logs and cooperation between data analysts and developers are critical. However, the problem is that overhead can occur when the log data is analyzed due to general characteristics of big data system as well-known 4Vs(Velocity, Various, Value...
Experimental characterization of stimulated Brillouin scattering (SBS) in a few-mode fiber (FMF) is demonstrated. The Brillouin gain spectra of intramodal and intermodal SBS are analyzed for different pump-probe pairs of four LP modes - LP01, LP11, LP21, and LP02 modes - guided in the fiber. A mode-division multiplexer composed of concatenated mode-selective couplers is applied for selective launching...
The characterization of stimulated Brillouin scattering (SBS) in an elliptic-core two-mode fiber (TMF) is experimentally demonstrated, where a mode selective coupler is applied for selective launching of LP01 or LP11 mode to the TMF. The intermodal SBS between counter-propagating LP01 and LP11 modes is observed for the first time, and its properties are presented in comparison with those of the SBS...
ANoC (Asynchronous Network-on-Chip) has been developed to solve problems of large number of cores in SoC (System-on-Chip) by giving asynchronism to every core. This new architecture requires new Testing methods different from the existing SoC Test, and it freshly needs the test of router and routing networks. This paper first offers high-speed testing architecture that tests more than one routers...
Low-power electronic circuit design for VLSI (Very Large Scale Integrated) testing is one of key design issues since power consumption is increased dramatically during test operations due to heavy transitions. Scan chain reordering has been one of the efficient low-power test technology to solve this problem. In this paper, we propose a new dynamic scan cell reordering technique that improves power...
In a recent VoD application, a stationary VoD server delivers video stream to a mobile device, particularly PDA, over wireless. Our objective is to develop a simple cost effective scheme which offers an acceptable video quality over a noisy wireless channel using a buffer size available at PDA. The key idea is that the sending rate at the server is faster than the playback rate at the handheld device...
Correction data of SBAS are classified to three categories such as the fast correction, the long term correction and the ionospheric correction. To retrieve and process the correction data, this paper modifies the software GPS receiver designed by CSLAB. The designed receiver can process all kinds of SBAS signals: WAAS, EGNOS, MSAS and GAGAN by just changing software. The performance of the implemented...
In an infrastructure network based on IEEE 802.11a/b/g wireless LAN, heterogeneous hosts such as desktop PCs and PDAs can be connected to it. We measured a performance of data transmission between these heterogeneous hosts. When a PDA as a mobile host is used for downloading data from its stationary server, i.e., a desktop PC, a PC and a PDA acts as a fast sender and a slow receiver, respectively,...
The objective of this study is to develop the simulation software for numerical control (NC) machining. This paper presents the visualization and analysis of cutting process in slope machining by using advanced octree method. A software based on advanced octree algorithms has been developed and used as the basis in this study. The suggested algorithm with supersampling techniques in computer graphics...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.