Sign inSubmit
Tips: “quotes” for a phrase · author:Lee · a DOI goes straight to its article

142 articles for “low frequency”
Set a search alert
Also matching:1 special issue
Research ArticleOpen accessIn the abstractDIELECTRIC CHARACTERIZATION OF LIQUID CONTAINING LOW ALCOHOLIC CONTENT FOR POTENTIAL HALAL AUTHENTICATION IN THE 0.5-50 GHz RANGEZurina Zainal Abidin, Fatin Nordalila Omar, Pavithiran Yogarajah et al.A potential method for detection and discrimination of alcoholic containing drinks for halal authentication using dielectric properties has been investigated. Behaviors of several pure alcohols, alcohol solution in water and also liquids with alcoholic contents were studied for verification purpose. Dielectric constant and dielectric loss factor for low concentration of ethanol solutions were measured over the microwave frequency from 0.5 … …American Journal of Applied Sciences, Vol. 11, Issue 7 · 24 Apr 2014 · 7,678 accessesView PDFCite
Research ArticleOpen accessIn the abstractNEURO FUZZY BASED PERFORMANCE ANALYSIS OF MULTIBAND ULTRA WIDE BAND ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING SYSTEMG. Joselin Retna Kumar, K. S. ShajiThis study proposes an efficient channel-estimation scheme for Multiband (MB) Orthogonal Frequency Division Multiplexing (OFDM)-based Ultra Wide Band (UWB) communication systems. One of the challenges in wireless system is the frequency selective fading caused due to multipath channel between the transmitter and receiver. The signal bandwidth in broad band cellular wireless systems typically exceeds the coherence bandwidth of the multipath … …Journal of Computer Science, Vol. 10, Issue 8 · 5 Mar 2014 · 6,624 accessesView PDFCite
Research ArticleOpen accessIn the abstractHARMONICS REDUCTION IN FRONT END RECTIFER OF UNINTERRUPTIBLE POWER SUPPLIES WITH ACTIVE CURRENT INJECTIONT. Chandrasekar, B. Justus Rabi, A. KannanHarmonics are the by-products of modern electronics devices so it is necessary to mitigate the harmonics and offer techniques to mitigation of harmonics. It is greatly hampered by a three phase rectifier used as a front-end ac-to-dc converter in many systems. High power factor is achieved by injecting high-frequency currents into the three-phase rectifier. This study presents the high power … …American Journal of Applied Sciences, Vol. 11, Issue 4 · 1 Feb 2014 · 6,807 accessesView PDFCite
Research ArticleOpen accessIn the abstractEmbedded Computer Based Active Vibration Control System for Vibration Reduction of Flexible StructuresVenkata Ratnam Tatavolu, Seetha Ramaiah PanchumarthyResearch on Active Vibration Control System (AVCS) is being carried out to reduce structural vibrations caused by unwanted vibrations in many application areas such as in space, aircraft structures, satellites, automobiles and civil structures (bridges), particularly at low frequencies. The unwanted vibration may cause damage to the structure or degradation to the structure’s performance. The AVCS comprises physical plant, a … …Journal of Computer Science, Vol. 9, Issue 7 · 15 Jun 2013 · 6,555 accessesView PDFCite
Research ArticleOpen accessIn the abstractDesign of Pass Band Filter in Hybrid Architecture Planar/Non-Radiative Dielectric Waveguide Integration TechnologyGharssallah Ali, Harizi HanenProblem statement: The expansion of RF, microwave and millimeter devices has revolutionized today’s ommunication and sensor systems. Low-cost, high-performance and mass producible millimeter wave technologies are vital for commercial broadband systems. Challenging issues are commonly faced in the design of low-loss integrated circuits for example high-Q band pass filter, which the planar technique is fundamentally limited in performance. Approach: In … …American Journal of Applied Sciences, Vol. 9, Issue 10 · 10 Aug 2012 · 7,094 accessesView PDFCite
Research ArticleOpen accessIn the abstractSentence Annotation based Enhanced Semantic Summary Generation from Multiple DocumentsA. Kogilavani, P. BalasubramanieProblem statement: The goal of document summarization is to provide a summary or outline of manifold documents with reduction in time. Sentence extraction could be a technique that is employed to pick out relevant and vital sentences from documents and presented as a summary. So there is a need to develop more meaningful sentence selection strategy so as to extract … …American Journal of Applied Sciences, Vol. 9, Issue 7 · 17 May 2012 · 7,008 accessesView PDFCite
Research ArticleOpen accessIn the abstractDetermining Potential Sites for Runoff Water Harvesting using Remote Sensing and Geographic Information Systems-Based Modeling in SinaiHossam H. Elewa, Atef A. Qaddah, Ayman A. El-FeelProblem statement: Sinai is increasingly suffering from an overwhelming water crisis. Runoff Water Harvesting (RWH) could be a solution for this problem. The determined promising drainage basins for RWH could be used by the decision makers to propose appropriate controlling systems to overcome the problem of water scarcity and for implementing runoff farming and rain-fed agriculture. Approach: Remote sensing, geographic … …American Journal of Environmental Sciences, Vol. 8, Issue 1 · 15 Feb 2012 · 8,488 accessesView PDFCite
Research ArticleOpen accessIn the abstractWideband E-Shaped Microstrip Antenna for Wireless Sensor NetworksG. Elangovan, J. Rajapaul PerinbamProblem statement: Wireless Sensor Networks (WSN) is currently receiving significant attention due to their unlimited potential. It is still very early in the lifetime of such systems and many research challenges exist, out of which one of the challenges is sensor processing and fusion under limited capacities, the most important component in sensor is its TX/RX antenna. Approach: For high-speed … …American Journal of Applied Sciences, Vol. 9, Issue 1 · 21 Nov 2011 · 7,109 accessesView PDFCite
Research ArticleOpen accessIn the abstractDesign of A Microwave Amplifier for Wireless ApplicationM. Habib Ullah, Badariah Bais, Norbahiah Misran et al.Problem statement: Low-Noise Amplifiers (LNA) are very indispensable components in the design of numerous types of communication receivers employed in microwave technology. This paper is presents the design and development of low bias(Vce = 8v, Ic =10 mA) single stage low noise microwave amplifier operating in 1.5GHZ frequency range, Gain 13dB ± 0.5dB, input/output return loss < -10dB, noise figure … …American Journal of Applied Sciences, Vol. 9, Issue 1 · 3 Nov 2011 · 8,231 accessesView PDFCite
Research ArticleOpen accessIn the abstractAnalysis of Fundamental Frequency Contour of Coded Speech Based on Multi-Pulse Based Code Excited Linear Prediction AlgorithmSuphattharachai ChomphanProblem statement: In low-bit-rate speech communication, speech coding deteriorates the characteristics of the coded speech significantly. An important feature of the speech is the fundamental frequency contour which determines the pitch information of the speech. It has been known that pitch information is one of the core parameter of the multi-pulse based code excited linear prediction (MPCELP) speech coder. Therefore … …Journal of Computer Science, Vol. 7, Issue 6 · 14 Jun 2011 · 6,463 accessesView PDFCite