Showing papers by "Chittagong University of Engineering & Technology published in 2012"
TL;DR: In this paper, three new square ferrocement jacketing techniques such as square jacketing with single layer wire mesh and rounded column corners (RSL), squared jacketing using single layer mesh with shear keys at the center of each face of column (SKSL) and squared jacket with two extra layers mesh at each corner (SLTL) are considered for this purpose.
59 citations
01 Dec 2012
TL;DR: The experimental results show that the proposed algorithm apparently preserves superior image quality and robustness under various attacks such as JPEG compression, cropping, sharping, contrast adjustments and so on.
Abstract: A combined DWT and DCT based watermarking technique with low frequency watermarking with weighted correction is proposed DWT has excellent spatial localization, frequency spread and multi-resolution characteristics, which are similar to the theoretical models of the human visual system (HVS) DCT based watermarking techniques offer compression while DWT based watermarking techniques offer scalability These desirable properties are used in this combined watermarking technique In the proposed method watermark bits are embedded in the low frequency band of each DCT block of selected DWT sub-band The weighted correction is also used to improve the imperceptibility The extracting procedure reverses the embedding operations without the reference of the original image Compared with the similar approach by DCT based approach and DWT based approach, the experimental results show that the proposed algorithm apparently preserves superior image quality and robustness under various attacks such as JPEG compression, cropping, sharping, contrast adjustments and so on
59 citations
TL;DR: In this paper, triple helical tapes made of mild steel with different helix angles, α=9°, 13°, 17°, and 21°, were examined for heat transfer enhancement.
58 citations
TL;DR: In this paper, the effects of different land uses on river water quality have been assessed using the Hydrologic Simulation Program (HSPF) and validated using relevant measurements by the Royal Irrigation Department (RID).
57 citations
01 Oct 2012
TL;DR: A location based early disaster warning and evacuation system for both normal and blind people using OpenStreetMap (OSM) is proposed and the experimental result demonstrates the effectiveness of the system.
Abstract: Natural Disasters have threatened mankind since history started. Due to geographic position and climate change, Bangladesh is one of most vulnerable countries to natural disasters. The country also lacks effective disaster preparedness system to confront natural disasters. Timely disaster warning and evacuation guideline can save lives of the people. In addition, a tourist or a blind people may face difficulties in finding safe area or shelter place prior to the occurrence of natural disasters. For this reason, we have proposed a location based early disaster warning and evacuation system for both normal and blind people using OpenStreetMap (OSM). The system is implemented on android mobile phone because of the burgeoning growth of smart phones in Bangladesh. So, our system comprises a third-party server named Disaster Management Server (DMS), android device with our application installed on it and user. The local weather office updates the disaster (tsunami, cyclone or flood) data on DMS. Device user registers on Android Cloud to Device Messaging (C2DM) server to get automatic notification of upcoming disaster otherwise user gets manual notification. The user communicates with DMS to have updated data sending the current position obtained by GPS or network provider. The probable disaster affected area is determined by ray casting algorithm. When our application recognizes the user in probable disaster zone then application will disseminate visual and audio disaster warning and evacuation guideline including shortest path of shelter or safe zone on the map of the application. Evacuation progress is also tracked using DMS and national identification of user. The experimental result demonstrates the effectiveness of our system.
50 citations
TL;DR: In this article, a unified measurement system with suction control (UMS_SC) was developed for measuring soil water characteristics curves (SWCC) and gas transport parameters under alternating drying and wetting cycles.
Abstract: [1] A unified measurement system with suction control (UMS_SC) was developed for measuring soil water characteristics curves (SWCC) and gas transport parameters under alternating drying and wetting cycles. The new system consists of a diffusion chamber, sample ring, porous plate, tensiometer, moisture sensor, oxygen electrodes, and air pressure gauges. The SWCC and gas transport parameters [gas diffusion coefficient (Dp) and air permeability (ka)] for two different porous materials, Toyoura sand and granulated slag, were simultaneously measured under drying and wetting cycles. The SWCC and gas transport parameters measured by UMS_SC were consistent with recent models and independently measured data on exactly the same materials using standard experimental setups from literature. For an applied water suction head of less than 50 cm and corresponding water saturation of around 0.3–0.5, the UMS_SC data documented hysteretic (nonsingular) behavior in both measured Dp and ka under repeated drying and wetting cycles. The hysteretic behavior was insignificant for water and air contents but large for both gas transport parameters when applying suction, and hysteretic effects were larger for air permeability than for gas diffusivity. Additionally, hysteresis in the percolation threshold (soil-air content where gas transport ceases due to interconnected water-filled pores) for both gas diffusion and air permeability was insignificant for both materials. These findings should be taken into account when developing models for diffusive and convective gas transport and their parameters in variably saturated porous media.
43 citations
TL;DR: In this paper, double helical tape inserts with different helix angles (9°, 15°, 21° and 28°) were used to augment heat transfer and pressure drop in the tube for Reynolds number ranging from 22,000 to 51,000.
39 citations
TL;DR: Tilt correction by the least square fitting with perpendicular offsets (LSFPO) is proposed and implemented for estimating rotation angle of the LP region and a new algorithm based on artificial neural network (ANN) is used for recognition of Korean plate characters.
36 citations
TL;DR: In this paper, the heat transfer performance and friction factor characteristics in a circular tube fitted with twisted wire brush inserts were investigated experimentally, and correlations were developed based on the data generated from this work.
24 citations
TL;DR: Assessment of the current wind and solar energy potential in Bangladesh finds that renewable-energy-based system will bring more environmental benefits than conventional power in terms of human health, reduction of air pollution, and decrease of noise, and so forth.
Abstract: Wind and solar energies are the alternative energy sources that can be used to supplement the conventional energy sources particularly in Bangladesh. In this work, the aim is to assess the current wind and solar energy potential in Bangladesh. The wind data for the five stations obtained from Local Government Engineering Department have been assessed, but only two of them seem to be eligible for energy production. Annual average, monthly average, and hourly average wind speeds and wind power densities were calculated from the wind data. The Weibull distribution parameters (c and k), the dominant wind directions, and the frequency distributions were also determined. Experimentally measured solar radiation data are not available over Bangladesh. Measured climatological data such as cloud cover and sunshine duration data of Bangladesh Meteorological Department from 1992 to 2001 used for the estimation of global solar radiation as they are correlated. Technoeconomic feasibility analysis is done for 100 kW grid connected wind and solar photovoltaic (PV) systems. Renewable-energy-based system will bring more environmental benefits than conventional power in terms of human health, reduction of air pollution, and decrease of noise, and so forth. However, in the above estimation, these were not considered.
23 citations
TL;DR: In this paper, the authors used the log-Pearson Type III distribution (LPIII) to estimate the expected extreme and satisfactory flows for fish habitat at Panchpukuria, Narayanhat, Telpari and Enayethat stations, respectively.
Abstract: Environmental flows have scarcely been considered in river water management in Bangladesh. This study attempts to assess the environmental flow requirements in the Halda River, Bangladesh. Thus, the objectives are to estimate the Halda River flow with different return periods/probabilities, which was done using the log-Pearson Type III distribution (LPIII), and to mitigate the environmental problems in the Halda River using the building block method. The LPIII distribution was used to estimate the expected extreme and satisfactory flows for fish habitat at Panchpukuria station and the expected extreme water levels at Panchpukuria, Narayanhat, Telpari and Enayethat stations. It was found that floods are likely to occur at least once in 2.1, 1.02, 1.75 and 1.25 years at Panchpukuria, Narayanhat, Telpari and Enayethat stations, respectively. The results of flow and water quality analyses suggest that environmental flow requirements cannot be achieved in this river throughout the year. The environmen...
TL;DR: In this paper, a comparative analysis of wind energy utilisation for power generation in South Asian countries is presented, showing that India is significantly ahead in wind energy utilization compared to other two countries Bangladesh and Pakistan.
TL;DR: An improved model of solar photovoltaic (PV) array along with the implementation of fuzzy logic as maximum power point tracking (MPPT) is presented, which is more accurate and with reduced complexity though considered discrete components.
Abstract: This paper presents an improved model of solar photovoltaic (PV) array along with the implementation of fuzzy logic as maximum power point tracking (MPPT). The proposed PV array behavioral model is more accurate and with reduced complexity though considered discrete components. The PV array model was well verified by considering the effect of change of environmental conditions, mainly intensity of solar irradiation (insolation) and temperature. The model was tested by feed a single phase inverter. MPPT control the operating voltage of PV arrays in order to maximize their power output as a result maximize the array efficiency and minimize the overall system cost. Using a Fuzzy logic based algorithm, the duty cycle of the converter inserted between source and load is adjusted continuously to track the MPP and compared with the conventional perturb and observed (P&O) method for changing environmental conditions. It was found that the Fuzzy logic based method can track the MPP more precisely and rapidly than the conventional one. In P&O method, if step size of input variable is very small, the accuracy in tracking MPP is sufficient but tracking speed becomes too slow. On the other hand if the step size is increased to imitate the rapidly changing weather conditions, accuracy deteriorates and unexpected results occur due to oscillation around a mean point although tracking speed increased. But in the case of proposed FLC whatever the step size of input variable it best suited to track MPP continuously and accurately. The obtained simulation results validate the competent of the solar PV array model as well as the fuzzy controller. DOI: http://dx.doi.org/10.11591/ijece.v2i6.1328 Full Text: PDF
18 May 2012
TL;DR: A remote exploration and control system has been developed using web Application, web server, database, GSM network, and Android mobile phone that automatically implements command like capturing picture and upload the captured picture to the server and control electrical devices.
Abstract: A remote exploration and control system has been developed using web Application, web server, database, GSM network, and Android mobile phone. Web application is used to control remotely an Android mobile phone and electrical devices connected with the mobile phone. Firstly, command is sent from the web Application and saved in database. The Android mobile phone reads the sent command from database and performs predefined procedure to execute the command and hence, generate outcome due to execution of the command. Thus, this system can be used as an exploration and control system because remote mobile phone automatically implements command like capturing picture and upload the captured picture to the server and control electrical devices. Command is implemented to capture picture automatically of the surrounding location and upload it to server. It can also send automatically GPS location of the mobile phone to server's database. So, it can be used to detect the device's geographical location and collateral condition. Hence, it can be used in monitoring as well as in security system. Finally, command is implemented for generating DTMF tone signal on Android phone. A DTMF detection circuit, interfaced with mobile phone, can automatically detect the DTMF tone signal and generates 4 bit digital code output. This digital output code can be utilized to control any electrical device.
26 Nov 2012
TL;DR: This paper proposes an algorithm for analyzing the vehicle image to extract the LP position in the image of the vehicle and is able to deal with candidate regions under different scale of the plate.
Abstract: Bangladeshi Vehicle License Plate Detection (BVLPD) plays an important and inevitable role in Vehicle License Plate Recognition (VLPR) system. The most challenging part of this method is to detect the region of the license plate from the vehicle image. In this paper, we propose an algorithm for analyzing the vehicle image to extract the LP position in the image of the vehicle. Initially, HSI color model is adopted to select a threshold for detecting candidate regions and then different geometrical properties of LP such as area, bounding box, aspect ratio are used to determine whether the candidate regions contain LP or not. Finally the candidate region is verified by intensity histogram. The proposed method is able to deal with candidate regions under different scale of the plate. In the experiment more than 100 images are used which are taken under different conditions such as uneven illumination, complex scenes, varied weather and varied distances from the vehicle to camera. The overall rate of success of the license plate detection algorithm is 85%.
01 Dec 2012
TL;DR: A new dimension of soft decoding turbo-like multi-stage threshold decoding (TLMTD) for self-orthogonal convolutional codes (SOCCs) and gives 0.20 dB more coding gain compared to MTD for equivalent SOCCs at the bit error rate less than 104.
Abstract: This paper presents a new dimension of soft decoding turbo-like multi-stage threshold decoding (TLMTD) for self-orthogonal convolutional codes (SOCCs) The TLMTD uses comparatively shorter constraint length conventional code of multi-stage threshold decoding (MTD) system The bit error performance is considered for several types of soft decoding algorithms on the additive white Gaussian noise (AWGN) channel When threshold value used as a priori threshold value for other decoding stage, TLMTD realizes better performance in waterfall and error floor regions Moreover, the TLMTD gives 020 dB more coding gain compared to MTD for equivalent SOCCs at the bit error rate less than 104
01 Dec 2012
TL;DR: In this paper, a new input-switched single-phase high performance bridgeless AC-DC Zeta converter (Inverse SEPIC) topology is proposed, where instead of using a single phase rectifier followed by a boost DC-DC converter, or using a bridge rectifier with two diodes and two switches, the converter's input is chopped at high frequency during positive and negative cycles by a single bidirectional switch.
Abstract: A new input-switched single-phase high performance bridgeless AC-DC Zeta converter (Inverse SEPIC) topology is proposed. Instead of using a single phase rectifier followed by a boost DC-DC converter, or using a bridge rectifier with two diodes and two switches, the converter's input is chopped at high frequency during positive and negative cycles by a single bidirectional switch to get step-up/step-down AC-DC conversion. Total Harmonic Distortion (THD) of the input current of the proposed circuit with small input current filter is low. Input power factor and the efficiency of conversion of the circuit are high. The circuit exhibits such performance with variable loads at constant frequency switching. No additional control is required to achieve the advantages.
26 Nov 2012
TL;DR: The experimental results show that the proposed algorithm apparently preserves superior image quality and robustness under various attacks such as JPEG compression, cropping, sharping, contrast adjustments and so on.
Abstract: Use of image has been increasing in many applications. With the rapid development of the network multimedia systems, one can easily duplicate digital image. A digital image watermarking is a valid solution of protecting illegal manipulation of digital image. It embeds some secret information into the host image and this information uses for authentication. In this paper a joint DWT and DCT based watermarking technique with low frequency watermarking with weighted correction is proposed. DWT has excellent spatial localization, frequency spread and multi-resolution characteristics, which are similar to the theoretical models of the human visual system (HVS). DCT based watermarking techniques offer compression while DWT based watermarking techniques offer scalability. These desirable properties are used in this combined watermarking technique. In the proposed method watermark bits are embedded in the low frequency band of each DCT block of selected DWT sub-band. The weighted correction is also used to improve the imperceptibility. The extracting procedure reverses the embedding operations without the reference of the original image. Compared with the similar approach by DCT based approach and DWT based approach, the experimental results show that the proposed algorithm apparently preserves superior image quality and robustness under various attacks such as JPEG compression, cropping, sharping, contrast adjustments and so on.
TL;DR: In this article, an experimental investigation was carried out for turbulent flow through a tube with perforated strip inserts, and the heat transfer performance was evaluated and found to be 2.3 times that of the plain tube based on constant blower power.
Abstract: An experimental investigation has been carried out for turbulent flow through a tube with perforated strip inserts. Strips were of mild steels with circular holes of different diameters. Flow varies, with ranging Reynolds numbers from 15,000 to 47,000. Air velocity, tube wall temperatures, and pressure drops were measured for a plain and strip-inserted tube. The heat transfer coefficient and friction factor were found to be 2.80 times and 1.8 times, respectively, that of the plain tube. The heat transfer performance was evaluated and found to be 2.3 times that of the plain tube based on constant blower power.
TL;DR: In this paper, a rheology originally proposed for high damping rubber bearing (HDRB) is applied to natural rubber bearing and lead rubber bearing along with its simplified form, and the modeling effects of bearings on the seismic responses of a multi-span continuous highway bridge via nonlinear dynamic analyses for two strong earthquake ground motions.
Abstract: A rheology originally proposed for high damping rubber bearing (HDRB) is applied to natural rubber bearing (RB) and lead rubber bearing (LRB) along with its simplified form. Comparing HDRB, the elasticplastic equilibrium responses were found to be more dominant than the rate-dependent response due to viscosity for RB and LRB. Moreover, the overstress in loading/unloading was found to be analogous. The dependency of nonlinear viscosity on current strain was found to be weak in contrast to the existence of considerable nonlinearity in elastic response. The original rheology model considers the nonlinear elastoplastic and viscosity induced rate-dependent behavior into account, while the viscosity effect is eliminated in the simplified version. The models are implemented in a finite element code. The modeling effects of bearings on the seismic responses of a multi-span continuous highway bridge are investigated via nonlinear dynamic analyses for two strong earthquake ground motions. Three analytical models of isolation bearings are considered for comparison: the conventional design models and the proposed two models. Model parameters for the bearings were determined for two temperature conditions: the room temperature (+23 ◦ C) and the low temperature ( 20 ◦ C) based on experimental data. The implication of the rheology models for response prediction of a prototype bridge is studied by comparing the rotation of a plastic hinge in pier and shear strain at the top of the bearing. The comparison suggests that the modeling of RB and LRB considering rheology properties is important for rational prediction of the seismic response of highway bridges, particularly at low temperature condition.
01 Dec 2012
TL;DR: In this article, a single phase high performance input side switched AC-DC Cuk converter is proposed, where a bidirectional switch is formed by a unidirectional semiconductor switch with proper positioning of the bridgeless diodes at the input ac side for power conversion for both positive and negative half cycle.
Abstract: A new single phase high performance input side switched AC-DC Cuk converter is proposed. A bidirectional switch is formed by a unidirectional semiconductor switch with proper positioning of the bridgeless diodes at the input ac side for power conversion for both positive and negative half cycle. Because of the high frequency input side switching, the power factor of the circuit is inherently corrected and it requires a small filter to make the input current near sinusoidal with limited THD. The significant improvement in THD makes the circuit a good choice in applications needing AC-DC conversion with power conditioning. The circuit exhibits such performances with variable loads at constant frequency switching with no additional control circuits. The efficiency of the circuit is also satisfactory. Analysis and simulation results of the circuit are obtained by using software simulation. The main advantage of this new AC-DC converter is its superior power quality.
01 Dec 2012
TL;DR: In this paper, an Energy Neutral Home (ENH) is designed and implemented for rural areas of Bangladesh, which is able to meet the energy requirement with renewable energy resources without taking any electricity from grid.
Abstract: Nowadays, Power crisis is one of the greatest problems of Bangladesh. Most of the electricity produced in Bangladesh is based on non-renewable energy resources. The reserve of Natural resources or non-renewable energy sources such as: fossil fuels, oil, natural gas etc are limited. So this is the time to search such a system where the residential areas of Bangladesh become Energy Neutral. This paper demonstrates such a system in which an Energy Neutral Home (ENH) is designed and implemented for rural areas of Bangladesh. The designed system is able to meet the energy requirement with renewable energy resources without taking any electricity from grid. In this research, biogas is used as primary renewable energy source for the generation of electricity.
TL;DR: A new method of embedding image data into the audio signal and additive audio watermarking algorithm based on Discrete Cosine Transformation (DCT) domain is proposed, demonstrating that the watermark is inaudible and this algorithm is robust to common operations of digital audio signal processing.
Abstract: Many effective watermarking algorithms have been proposed and implemented for digital images and digital video. However, a few algorithms have been proposed for audio watermarking. This is due to the fact that, human auditory system (HAS) is far more complex and sensitive than human visual system (HVS). In this research work, a new method of embedding image data into the audio signal and additive audio watermarking algorithm based on Discrete Cosine Transformation (DCT) domain is proposed. First, the original audio is transformed into DCT domain. The DCT coefficients are divided into a fixed number of subsections and the energy of each subsection is calculated. Next, watermark is generated from image by image processing algorithm. Watermarks are then embedded into selected peaks of highest energy subsection. Experimental results demonstrate that the watermark is inaudible and this algorithm is robust to common operations of digital audio signal processing, such as noise addition, re-sampling, requantization and so on. To evaluate the performance of the proposed audio watermarking method, subjective and objective quality tests including Bit Error Rate (BER) and Signal to Noise ratio (SNR) are conducted.
01 Dec 2012
TL;DR: The design and experimentation of a novel secure real time method to control device is presented, which can be useful for the people who are working in research laboratory, industry & education in the field of Communication, Control, wireless technology etc.
Abstract: In the age of electronic systems it is important to acquire and control information from everywhere. Here we present a novel secure real time method to control device. We summarizes a study conducted to examine the feasibility of implementing Global System for Mobile Communications (GSM), using Duel Tone Multi-Frequency (DTMF) as an alternative means of communication to Radio Frequency (RF) to control electrical appliances. In remote communication, DTMF signal can replace RF signal for the advantage of simplicity and audibility. A user can send DTMF tone to control home appliances or machines in industries. Any GSM mobile phone can be employed to send DTMF tone. The advantage of this system is the use of GSM technology for communication and at a time control of many devices. This paper deals with the design and experimentation, which can be useful for the people who are working in research laboratory, industry & education in the field of Communication, Control, wireless technology etc.
26 Nov 2012
TL;DR: In this article, the GE 3.6 MW wind turbine model was implemented in Matlab and Simulink and tested by varying the aerodynamic parameters C p, max and λ opt.
Abstract: This paper describes the implementation and investigation the functionality of the GE 3.6 MW Wind Turbine model implemented in Matlab® and Simulink® when exposed to a wind-step. The robustness of the Wind Turbine is tested by varying the aerodynamic parameters C p, max and λ opt . It is found that, the implemented model operate as expected in different wind speed regions under different disturbances e.g. wind speed step, grid-fault. However, while simulating in the low-wind speed region, it is found that, the pitch controller does not work according to the expected behavior. The pitch-angle tends to change, although it should not be the case for low-wind speed operation.
26 Nov 2012
TL;DR: An ontology (Fruit Ontology) is proposed of agricultural sub-domain which is designed with OWL Description Logic (DL) language and described the each steps of designing the “Fruit” ontology briefly.
Abstract: Agricultural knowledge is so distributed, heterogeneous and polymorphic that current web architecture may unable to find the desired search results. So ontology of semantic web architecture is used for better search results. Semantic web makes the data of the web machine understandable and ontology is the core step of semantic web technology. Ontology captures the domain knowledge in a generic way and provides a commonly agreed understanding of a domain. It helps the search engine to find out the meaningful and scientifically correct information. In this paper, an ontology (Fruit Ontology) is proposed of agricultural sub-domain which is designed with OWL Description Logic (DL) language. Agricultural ontology is used by many organizations for better agricultural information service (AIS) or for adapting reliable information and communication system in agriculture. This paper also describes the each steps of designing the “Fruit” ontology briefly. For designing ontology AGROVOC is used as the base vocabulary. AGROVOC is developed by the Food and Agricultural Organization (FAO) of United Nations which is used all over the world for indexing, retrieving and organizing data in agriculture information system.
01 Dec 2012
TL;DR: An investigation on IP-based mobility management schemes in WMNs is conducted and the open challenges at the end are proposed.
Abstract: Wireless mesh networking (WMN) has received unprecedented attention from the research community due to its cost effectiveness for providing high bandwidth internet access. For realizing large scale wireless mesh network with seamless communication, mobility management is a vital issue. Although remarkable contribution has been made on mobility management in WMNs, it needs more attention for improvement of real time communication. In this article, an investigation on IP-based mobility management schemes in WMNs is conducted. By analyzing the existing and current research works on mobility management in WMNs, this paper proposes the open challenges at the end.
18 May 2012
TL;DR: In this paper, a series of polycrystalline spinel ferrites with composition Ni 0.27 Cu 0.10 Zn 0.63 Al x Fe 2−x O 4 for x values ranging from 0.00 to 0.16 in steps of 0.04 and sintered at 1300°C have been prepared and investigated by the standard double sintering ceramic technique.
Abstract: A series of polycrystalline spinel ferrites with composition Ni 0.27 Cu 0.10 Zn 0.63 Al x Fe 2−x O 4 for x values ranging from 0.00 to 0.16 in steps of 0.04 and sintered at 1300°C have been prepared and investigated by the standard double sintering ceramic technique. The effect of Al-ion substitution on the AC electrical resistivity and dielectric properties at different frequencies from 100 Hz up to 120MHz was studied. The AC resistivity results were discussed in terms of the electron hopping model. The dispersion of the dielectric constant was discussed in the light of Koop's phenomenological theory and Maxwell-Wagner interfacial polarization. The dielectric loss tangent exhibit dielectric relaxation peaks which are attributed to the coincidence of the hopping frequency of the charge carriers with that of the external fields. All the variations are explained on the basis of Cu2+ and Cu+; Ni2+ and Ni3+; Fe2+ and Fe3+ concentrations on octahedral sites and electronic hopping frequency between Fe2+ and Fe3+ ions and hole transfer between Cu2+ and Cu+; Ni2+ and Ni3+ over octahedral site.
26 Nov 2012
TL;DR: In this paper, the authors pointed out the possible energy resources for electricity generation in Bangladesh with the help of scientific analysis and available statistics, and proposed underground coal as the ultimate choice.
Abstract: Energy and economy are directly correlated. Now-a-days the development of a country is measured by the energy consumption rate of that country. Bangladesh's energy infrastructures are quite small, insufficient and poorly managed with per capita energy consumption of 220KWh only. Bangladesh is steadily climbing up the development ladder and industries are shifting towards automation process. Energy and power need to act as a key catalyst in helping Bangladesh in this endeavor. The installed capacity of the power plants of Bangladesh is around 8000MW for supporting the demand of around 7000MW. However due to failure in the proper fuel management in the last few years the whole country is suffering from 1500–1800MW of shortage. In order to cater the growing demand and sustain the development phase it is the high time to think about the underground coal as the ultimate choice. This paper is one such attempt in pointing out the possible energy resources for electricity generation in Bangladesh with the help of scientific analysis and available statistics.
01 Dec 2012
TL;DR: A cooperative relay selection scheme where one of the inactive STj which achieves the primary target Rtarget will be selected as a best relay to forward the primary information is proposed.
Abstract: We consider an underlay cognitive radio network consisting of a single pair of primary transmitter-receiver PTx-PRx and a group of M secondary transmitter-receiver pairs STx-SRx within the transmission range of the primary system. Secondary transmitters are partitioned into two groups K, KeM active secondary transmitters ST i , i e {1, 2,…, K} which may transmit data with the co-existence of PTx below a certain interference threshold to the primary receiver and (M-K) inactive secondary transmitters ST j , je {1, 2,…, (M-K)} which are in idle state, ready to assist the primary system when the data rate between PTx and PRx over a direct link falls below the target rate R target . In this paper, we propose a cooperative relay selection scheme where one of the inactive ST j which achieves the primary target R target will be selected as a best relay to forward the primary information. Simulation results show the effectiveness of our proposed system.