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Tendency in the Transformation of Agricultural Land into Non-Agriculture: some selected areas in Bangladesh
(Review of Pacific Basin Financial Markets and Policies., 22-11-07) Rokonuzaman1, M; Saha, G C; Alam, Mohammad Khurshed
The survey was conducted to - estimate the annual conversion of agricultural land into non-agriculture, investigate the present pattern of non-agricultural uses of the converted land, suggest suitable policy measures towards the protection of farmland in the country. Besides, consequent loss of crop production during the ten years of 2001 to 2010 was estimated. There were three Upazila from Mymensingh district: Mymensingh Sadar, Bhaluka, and Fulbaria; another three from Narshindi district: Narshindi Sadar, Belabo, and Polash Upazila as local of the study,respectively. Data were collected from 18. 01.12 to 10.03.12. The respondents were the household head. The total sample size was 180, of which 20 were from each Upazila. Data were collected using a face-to-face interview schedule. The data indicated that conversion of agricultural land 0.42 percent per year. Information regarding nonagricultural uses of converted land indicates that more than half (55 percent) of the converted land was used in housing predominantly in urban villages (53 percent) as expected. The subsequent two important uses were in constructing roads and usiness enterprises covering 11 and 8 percent respectively. The non-reported area of usewas also substantial (18 percent). Such land was the largest in rural villages (20 percent). Among different residential statuses of the households, the second most crucial utilization in peri-urban villages was road construction, covering 21 percent of its converted land. The respondents have put forward some suggestions for arresting the current rate of land conversion. Their ecommendations include the following agriculture should be made more profitable and attractive (50 percent); the special tax should be imposed on the conversion of land (29percent), and interestingly, area wise ceiling may be fixed for non-agricultural uses of land (9 percent), and tax exemption may be offered for commercial farms, and the agro-based industries scored same (9 percent). It was concluded that crop loss amounting to US$197,963,29 per year happens due to the conversion of farming land into non-agriculture purposes in Bangladesh as a whole.
Microcomputer Based Dish Antenna Position Control System
(IEEE, 1998-12-18) Saha, Pran Kanai; Ahsan, Syed Shabiul; Bhuyan, Muhibul Haque; Islam, Kamarul; Alam, AHM Zahirul
This paper presents a microcomputer-based control system to position a small dish antenna at a desired elevation and azimuth angle for maximum power reception from the satellite. Here satellite position is used as an input of the system. Two dc motors (one for azimuth position while the other for elevation position of the antenna) are used to position the dish antenna. Continuous pulses are sent to the motor control circuit through the parallel port of the computer to move the dish to the desired position. A prototype dish antenna is constructed and then positioned by using the developed control system. Results show a very good agreement between the desired position and the actual position of the dish antenna.
Workforce in Information Technology (IT): Australian Perspective
(Dhaka University, 2003) Islam, MMObaidul; Uddin, Md.Farid
Now-a-days, Information and Communication Technology (ICT) is the pillar of success of an organization. various studies show that there is acute shortage of skilled IT workforce all over the world. Managers throughout the world are experiencing a difficult situation of unprecedented demand for IT workers. Australia is not excluded from it. the future of the Australian IT industry lies on the capacity of Australian education and training systems to supply skilled people to the IT industry. Inn this paper, an attempt was made and suggestions were given to figure out the shortage of IT workers inn Australia and how to fulfill the increasing requirements.
Close-Relationship Management between Banks and Small Business: Exploring the interactions between policies
(Dhaka University, 2003-06) Uddin, Md.Farid; Islam, MMObaidul
Banks are the largest sources of finance for small business. Banks are known as have stable and long lasting relationship with their customers, which is why development of customer relations is a crucial strategic issue in banking. However, a basic problem in banking is that the customer base is heterogeneous, ranging from homogeneous segments of customers with the same preferences to customer with individual demands for customized services. A key issue in banking is that how bank managers view different strategies to develop their customer relations. This paper investigates how bank branch managers perceive the heterogeneity of their market and how the bank’s relationship strategy affects the development of customer relations. To this and 100 branch bank managers answered a questionnaire, which was processed by SPSS. Results suggest that how bank managers ma perceive customer relationship development strategy is determined by the heterogeneous market and bank’s relationship strategy. This suggests that banks relationship development need to focus more on customer orientation, and that realized strategies need to support this. Bank can be more customer-oriented in their lines of services to small business. It can be proofed that a bank should design a complete customer oriented relationship package with relationship characteristics like offering start-up incentive, monitoring during the period of loan and other efforts should continue to be made to improve the situation in particular to improve the exchange of information between banks and users of finance, which will help the loan users to run the business effectively and efficiently. The effort also continues to be made to improve the situation in Bangladesh between bank and small business relationship from existing and newly evolved ideas.
To Improve HiSIM-SOI for Real Application
(Hiroshima University, 2004-03-31) Bhuyan, Muhibul Haque; Mattausch, Mitiko Miura-
SOI-MOSFET is a candidate for next generation integrated circuit technology due to its reduced junction capacitances and improved subthreshold swing. However, to utilize the technology for circuit application, a robust circuit model is needed. A complete surface-potential-based fully depleted SOI-MOSFET model for circuit simulation has been developed by our group and is named HiSIM-SOI [1, 2]. This model considers device features explicitly as well as preserves the charge conservation. To improve HiSIM-SOI for real application is the purpose of this present work.
To Improve HiSIM-SOI for Real Application
(Hiroshima University, 2004-03-31) Bhuyan, Muhibul Haque; Mattausch, Mitiko Miura-
SOI-MOSFET is a candidate for next generation integrated circuit technology due to its reduced junction capacitances and improved subthreshold swing. However, to utilize the technology for circuit application, a robust circuit model is needed. A complete surface-potential based fully depleted SOI-MOSFET model for circuit simulation has been developed by our group and is named HiSIM-SOI [1, 2]. This model considers device features explicitly as well as preserves the charge conservation. To improve HiSIM-SOI for real application is the purpose of this present work.
Minimal Order Bilinear Observer for High Performance Control of Induction Motor Taking Core Loss into Account
(The Society of Instrument and Control Engineers, 2004-05-01) Mannan, Mohammad Abdul; Toshiaki, Toshiaki; Tamura, Junji
This paper presents a minimal order rotor current and rotor flux observer for an indirect field-oriented induction motor drive with consideration of core loss due to eddy current from the viewpoint of nonlinear observer using bilinear model. The state equations for an induction motor were derived which behaved as a bilinear system in terms of the product of input and state variables. The design of the proposed observer is based on Lyapunov's stability method whose estimation error converges to zero exponentially irrespective of the inputs. We have also proposed a control system by using multi-input and multi-output optimal regulator theory. The estimated rotor current and rotor flux are fed back to the multi-input and multi-output optimal regulator. Simulation results are presented to show the validity of the proposed controller as well as rotor current and rotor flux estimation of induction motor drive.
DSP based Three Level PWM for Two Phase VSI
(IEEE, 2004-12-28) Bhuyan, Muhibul Haque; Rahman, Kazi Mujibur; Choudhury, Mohammad Ali
Three level PWM schemes offer more output voltage and less switching losses as compared to the two-level PWM strategy. For inductive loads, due to lack of zero voltage freewheeling path in a three level PWM, the load current waveform distorts and contains unwanted low order harmonics. Analysis of inverter performance with three-level PWM driving inductive load has not been investigated so far. In this paper the performance of a two-phase inverter driving a two-phase induction motor is investigated with three-level PWM technique. The three-level PWM scheme is modeled using regular sampling strategy. The scheme is implemented with a TMS320C50 digital signal processor and tested on a prototype MOSFET inverter with a 0.5HP two-phase motor load. The experimental performance is found in good agreement with the theoretical results, validating the theoretical model of the three-level PWM for two-phase VSI.
The Surface-Potential-Based model HiSIM-SOI and its Application to 1/f Noise in Fully-Depleted SOI-MOSFETs
(Nano Science and Technology Institute (NSTI), 2005-05-08) Sadachika, N.; Yusoff, M. M; Uetsuji, Y.; Bhuyan, Muhibul Haque; Kitamaru, D.; Mattausch, H. J.; Miura-Mattausch, M.
The fully-depleted SOI-MOSFET model HiSIM-SOI for circuit simulation is the first model for circuit simulation based on a complete surface-potential description. HiSIM-SOI solves the surface potentials at all three SOI-surfaces perpendiculars to the channel surface self-consistently. Besides, verification against measured I-V characteristics, HiSIM-SOI is also verified with a 1/f noise analysis, sensitive to the carrier concentration and distribution along the channel. During the noise analysis, it was found that the carrier concentration increase in SOI-MOSFET leads to an enhanced 1/f noise in comparison with the bulk-MOSFET. Therefore, HiSIM-SOI predicts that further reduction of the silicon-layer thickness necessary for achieving higher driving capability will cause unavoidable noise enhancement.
Fuzzy-Logic-Based Self-Tuning PI Controller for Speed Control of Indirect Field-Oriented Induction Motor Drive
(The Society of Instrument and Control Engineers, 2005-08) Mannan, Mohammad Abdul; Muratra, Toshiaki; Tamura, Junji
In this paper, a new self-tuning proportional and integral (PI) controller based on fuzzy logic is proposed to improve the performance of conventional PI speed control of induction motor (IM) taking core loss into account. A new parameterization technique to tune the proportional and integral gains of PI controller is adopted by using a single parameter (h) from the knowledge of pole placement technique. To tune the parameter h depending on the operating points, a simple fuzzy logic system is designed where only one input, one output variables, three membership functions for each input-output variable, and three fuzzy rules are used. Since the poles of PI speed controller are placed in negative real values by using the proposed parameterization technique, the speed controller always works in stable region. Moreover, the overshoot and steady state error problems are also overcome by changing of h based on the proposed fuzzy system under the variations of load torque and parameters. The performance of proposed fuzzy-logic-based self-tuning PI controller has been demonstrated through the simulations. The simulation results confirm that the excellent desired speed is achieved against the variations of load torque and parameters without any overshoot and steady state error by using the proposed system.
Speed Control and a Full-Order State Observer for Efficiency Optimized Induction Motor
(Taylor and Francis, 2005-09) Mannan, Mohammad Abdul; Murata, Toshiaki; Tamura, Junji; Tsuchiya, Takeshi
To improve the efficiency of an induction motor (IM), an algorithm has been developed in terms of slip frequency. A discrete-time multi-input and multi-output (MIMO) optimal regulator is proposed to achieve the desired speed with efficiency optimization. Furthermore, a full-order observer is proposed to estimate rotor flux and magnetizing current because these states of IM are feedback to design the proposed controller. The performances of the efficiency optimized speed control and observer system have been verified by simulation. Regarding the simulation study, it can be stated that the proposed controller and observer system are suitable for the implementation of efficiency optimized speed control of IM.
Design of A Two-Level PWM Scheme for Two Phase Voltage Source Inverter using DSP
(Multimedia University, Malaysia, 2005-11-24) Bhuyan, Muhibul Haque; Rahman, Kazi Mujibur
Digital Signal Processor (DSP) TMS320C50-based two-level PWM scheme for two-phase voltage source inverter is proposed. The performance of this inverter is investigated by driving a two-phase induction motor. The experimental result is found in good agreement with the theoretical ones.
Investigation of short channel effects in MOSFET using the device simulator, MEDICI
(Multimedia University, Malaysia, 2005-11-24) Bhuyan, Muhibul Haque; Khan, Sher Shermin Azmiri
Short channel effect is investigated using MEDICI. For long and short channel MOSFETs, threshold voltages are calculated using equations obtained from the literature. Calculated and simulation results show that one-dimensional device equation needs to be modified to include the short channel effects
Microcomputer Based Dish Antenna Position Control System with Autocalibration Option
(IEEE, 2005-12-28) Bhuyan, Muhibul Haque; Saha, Pran Kanai
This paper presents a microcomputer-based control system to position a small dish antenna at a desired azimuth and elevation angle. The desired angle of rotation is the input data of the system. Two dc motors (one for azimuth position while the other for elevation position of the antenna) are used to position the dish antenna. Signals are sent to the motor control circuit through the parallel port of the computer. Due to aging, the component behavior of the motor control circuit may change, and as no feedback system is included auto-calibration system has been incorporated with the system so that the system can be freshly calibrated at any time. A prototype dish antenna is constructed and then positioned by using the developed control system. Results show a very good agreement between the desired position and the actual position.
MOS device simulation using MEDICI
(Bangladesh Electronics and Informatics Society, 2005-12-31) Bhuyan, Muhibul Haque; Khan, Sher Shermin Azmiri
MEDICI is a powerful device simulation program that can be used to simulate the behavior of MOS and other semiconductor devices. The program can be used to predict electrical characteristics for arbitrary bias conditions. In this paper, various characteristics of the conventional bulk MOS device have been simulated using the MEDlCl. Gate and drain characteristics, mobility and carrier concentration profiles, and effects of various device parameters on the threshold voltage of MOSFET are simulated. Finally, a CMOS is constructed and simulated to verify the MOS structure. Also, simulation results of threshold voltages are compared with the calculated results using the conventional bulk MOSFET equation.
Automatic Electric Billing System using Digital Wattmeter and Powerline Carrier System
(The CSE Review, Shahjalal University of Science and Technology, Volume 2, 2006-01-01) Islam, Md Manirul
The "Information Age" in electricity metering has arrived. Today's power measurement applications demand that energy meters be both intelligent and powerful to satisfy the challenges of a competitive marketplace. DIGITAL WATTMETER with a suitable LED display is such a potent device to accurately measure energy consumption and demand in the real world so to reduce system losses and consumer dissatisfaction. This paper describes an alternative infrastructure design of the electric meter reading system to eliminate the manual meter reading by remote monitoring of the power consumption and meter status using powerline carrier system and digital wattmeter. At a certain predefined time interval, the central system connected to each meter through powerline networking would collect the readings and automatically print the billing at the end of the month.
A Fuzzy-Logic-Based Self-Tuning PI Controller for High-Performance Vector Controlled Induction Motor Drive
(Taylor and Francis, 2006-04) Mannan, Mohammad Abdul; Murata, Toshiaki; Tamura, Junji; Tsuchiya, Takeshi
Vector control (VC) of an induction motor (IM) is generally implemented by applying a proportional and integral (PI) controller owing to its simple design technique. The performance of an IM deteriorates under the variations of load torque and parameters where the gains of a PI controller are kept constant. Therefore this paper presents a self-tuning PI (ST-PI) controller based on fuzzy logic control (FLC) theory for high performance of an IM. According to the pole placement technique, the gains of a PI controller are tuned by applying FLC. The effectiveness of the proposed fuzzy-logic-based ST-PI controller is demonstrated through simulation results. These clarify that the proposed ST-PI controller can provide better response than a conventional PI controller.
Energy Model Based Loss-Minimized Speed Control of Induction Motor with a Full Order Observer
(John Wily and Sons, Inc., 2006-05) Mannan, Mohammad Abdul; Murata, Toshiaki; Tamura, Junji
In this paper, a loss-minimization algorithm is developed to achieve maximum efficiency in terms of slip frequency. The optimal value of slip frequency can be obtained by minimizing all controllable losses of the induction motor (IM). The ratio of magnetic energy converted to torque (WT) to magnetic energy stored in the rotating field (Wq) is defined in terms of slip frequency to obtain an error function that is used to design a controller to achieve the desired speed. Since the energy model of the IM can be expressed by the multi-input and multioutput (MIMO) system, an MIMO optimal regulator is proposed to achieve the desired speed with maximum efficiency. To design an optimal regulator, it is necessary to measure all state quantities. But WT and Wq cannot be measured directly. Therefore, a full-order observer is proposed to estimate these state quantities. The gains of the observer system are calculated by using the pole placement technique. Consequently, the observer system becomes stable. The performance of the proposed controller and observer system are verified by using simulation. With regard to the simulation results, it can be concluded that the desired speed can be achieved by using the proposed controller and the unknown state quantities can be estimated properly by using the proposed observer system.
IP Controller Based Vector Control of Induction Motor Taking Core Loss into Account
(John Wily and Sons, Inc., 2006-05) Mannan, Mohammad Abdul; Murata, Toshiaki; Tamura, Junji
This paper presents speed and current control of the induction motor (IM) taking core loss into account based on integral plus proportional (IP) control strategy. The proposed IP controller can overcome the problems (such as overshoot, instability under the variations of parameters and load torque) of the conventional PI controller. The performance of the proposed IP controller and PI controller is compared. The performance comparison of the IP controller and the PI controller is verified by using Matlab/Simulink.
A Study of Marketing Mix Adaptation Requirement with Export Performance by the Domestic Exporters of Leather Goods to the International Market
(Journal of Business and Technology, 2006-07) Karim, Khondaker Sazzadul; Rahman, Md. Lutfor
According to the MIXADAPT model, export performance depends upon the marketing mix adaptation. Many studies found the existence of a mostly positive effect of marketing mix adaptation on export performance, even though controversies still exist regarding the determinants of export performance and whether there are other internal and external determinants other than marketing mix that have an impact on export performance. In the case of the leather industry in Dhaka city, no significant relationship was found between export performance and adaptation of the marketing mix. Price adaptation is the only variable that significantly affects export performance. The findings suggest further research incorporating other internal and external variables such as management attitude and perceptions, management characteristics, industry characteristics, foreign market characteristics, and domestic market characteristics to be incorporated with the MIXADAPT model to explain the export performance of the leather industry in Bangladesh.