98 research outputs found
An exploratory research on grammar checking of Bangla sentences using statistical language models
N-gram based language models are very popular and extensively used statistical methods for solving various natural language processing problems including grammar checking. Smoothing is one of the most effective techniques used in building a language model to deal with data sparsity problem. Kneser-Ney is one of the most prominently used and successful smoothing technique for language modelling. In our previous work, we presented a Witten-Bell smoothing based language modelling technique for checking grammatical correctness of Bangla sentences which showed promising results outperforming previous methods. In this work, we proposed an improved method using Kneser-Ney smoothing based n-gram language model for grammar checking and performed a comparative performance analysis between Kneser-Ney and Witten-Bell smoothing techniques for the same purpose. We also provided an improved technique for calculating the optimum threshold which further enhanced the the results. Our experimental results show that, Kneser-Ney outperforms Witten-Bell as a smoothing technique when used with n-gram LMs for checking grammatical correctness of Bangla sentences
A non-contact capacitance type level transducer for liquid characterization
The liquid properties such as buoyancy, pressure at
a depth, relative electrical permittivity, electrical
conductivity, thermal conductivity, absorption of
radiation, liquid surface reflection of sound or light
waves, are used to design the different types of liquid
level transducers for liquid level measurement in any
process industry. The contact-type level-sensing
transducers have the disadvantage that their
characteristic properties may change due to physical
or chemical reaction between the liquid and the
probing material, and hence may affect accuracy
besides their life time.
The non-contact-type level-sensing probes may
have longer life period, but they are comparatively
costly and require various environmental and
experimental precautionary measures when being
used.
In this paper, a low-cost non-contact capacitance
type liquid level measuring technique has been
designed and used for liquid identification objectives.
The results obtained are very much consistent with the
theoretical derivations
Prediction of signal attenuation due to duststorms using mie scattering
The present trend in radio design calls for the use of frequencies above 40 GHz for short links carrying wide-band digital communication signals. In order to utilize the new frequency band efficiently, signal attenuation studies due to duststorms is needed urgently for desert areas. This paper presents a mathematical model which has been developed to predict the signal attenuation due to duststorm. The proposed model enables the convenient calculation of the signal path attenuation based on Mie solution of Maxwell's equations for the scattering of electromagnetic wave by dust particles. The predicted values from the proposed mathematical model are compared with the measured values observed in Saudi Arabia and Sudan and show relatively close agreement
Disorder raises the critical temperature of a cuprate superconductor
With the discovery of charge density waves (CDW) in most members of the
cuprate high temperature superconductors, the interplay between
superconductivity and CDW has become a key point in the debate on the origin of
high temperature superconductivity. Some experiments in cuprates point toward a
CDW state competing with superconductivity, but others raise the possibility of
a CDW-superconductivity intertwined order, or more elusive pair-density wave
(PDW). Here we have used proton irradiation to induce disorder in crystals of
LaBaCuO and observed a striking 50% increase of
accompanied by a suppression of the CDW. This is in clear
contradiction with the behaviour expected of a d-wave superconductor for which
both magnetic and non-magnetic defects should suppress . Our
results thus make an unambiguous case for the strong detrimental effect of the
CDW on bulk superconductivity in LaBaCuO. Using tunnel
diode oscillator (TDO) measurements, we find evidence for dynamic layer
decoupling in PDW phase. Our results establish irradiation-induced disorder as
a particularly relevant tuning parameter for the many families of
superconductors with coexisting density waves, which we demonstrate on
superconductors such as the dichalcogenides and LuIrSi.Comment: 10 pages, 7 figure
Capacitive transducer circuits for liquid level measurement
This work is making use of the capacitive element that is made of two electrodes - a column of liquid the level of which is to be measured, and a metallic tube that is pulled and fitted over a PVC tube of accordingly smaller dimensions. Both of the electrodes are provided with contact terminals for easy connection within a bridge circuit, which is powered by a sinusoidal source of given amplitude and known frequency. Precautionary measures are taken for improved linearity and minimal interference of the power supply on experimental data obtained as a result of measurement. The experimental data shows good consistency with the theoretical details and
derivations
Optimum concentric circular array antenna with high gain and side lobe reduction at 5.8 GHz
The significance of high gain directional antennas stems from the need to cope up
with the everyday progressing wireless communication systems. Due to low gain of the widely
used microstrip antenna, combining multiple antennas in proper geometry increases the gain
with good directive property. Over other array forms, this paper uses concentric circular array
configuration for its compact structure and inherent symmetry in azimuth. This proposed array
is composed of 9 elements on FR-4 substrate, which is designed for WLAN applications at
5.8GHz. Antenna Magus software is used for synthesis, while CST software is used for
optimization. The proposed array is designed with optimum inter-element spacing and number
of elements achieving a high directional gain of 15.7 dB compared to 14.2 dB of available
literature, with a high reduction in side lobe level of -17.6 dB
2.45 Ghz passive RFID tag antenna mounting on various platforms
This chaptcr presents the design of Microwave RFID ug antenna. The lag ameDnaS are designed using the electromagnetic simulation software called CST for a passive RHO tag operaling in the Microwave frequency band. A microwave band ug antenna was designed and simulated for 2.45GHz. A high gain (5.842dB), a good impedance matching with the microchip (-30.0 dB Retum Loss) and a satisfactory read range performance (up to 5 m) was obtained. One approach of designing RFlO ug is thai the lag should be less sensilive to lhe various types of objects. The effects of obstacles on antenna's characterislics have been investigated by placing the tag amenna against a meullic, rubber, glass and wood surfaces. Simulation results show slighl variations which is within tolerance rang
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