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not available Bangladesh J. Zool. 49(1): 169-173, 2021

The objective of this paper is to present and analyze the results of simulated steam generator tube rupture (SGTR) accident in VVER-1200 Nuclear Reactor in PCTRAN. In simulating the accident, 100% of one full tube rupture has been considered. The simulation result shows that pressure and temperature changes slightly but it doesn’t effect on reactor power and neutron flux because the VVER-1200 nuclear power reactor has several safety features which undertake the situation and as a result, reactor trip did not happen. The data obtained from the simulation are satisfactorily consistent with PSAR (Preliminary Safety Assessment Report) data regarding SGTR accident. These findings are expected to provide useful information in understanding and evaluating plants capability to mitigate the consequence of SGTR accident.

VO2 thin films were grown on conducting oxide underlayer SrRuO3 buffered SrTiO3 (111) and Si/SiO2 substrates, respectively, using sputtering. X-ray diffraction phi-scans revealed the epitaxial nature of the VO2 films grown on SrRuO3 buffered SrTiO3 and polycrystalline structure for films grown on SrRuO3 buffered Si/SiO2. X-ray photoelectron spectroscopy confirms a dominant presence of V4+ in both films and establishes a high-quality growth of single-phase VO2 films. Temperature and electric-field driven metal-insulator-transition in both the in-plane and out-of-plane configurations were investigated. Depending on the configuration, the resistance change across the metal-insulator-transition varies from a factor of 1.57–3. The measured resistance in each state as well as the magnitude of resistance change were similar during temperature and electric-field driven metal-insulator-transition. To shed light on the suppressed metal-insulator-transition characteristics due to the current shunting effect from conducting SrRuO3 bottom electrode, a distributed resistance network model is proposed and benchmarked against reports from the literature. The results demonstrate the growth of high-quality VO2 on conducting SrRuO3 layers and their electrical behavior, which is of particular interest for all-oxide electronic devices utilizing phase transitions such as resistive memory and neuromorphic oscillators.

LPG (Liquefied petroleum gas) is a form of natural gas which has been liquefied under extreme pressure and then contained in a metal cylinder. It is very sensitive to fire and can cause a great disaster if it's exposed to any fire source without precaution. LPG is more available than any other natural gas so most people choose LPG for their needs like cooking and other needs. So the event of gas leakage or blast occurring by leaked gas is frequently seen and heard. In this paper, a device has been introduced to prevent any possible accident from happening. It is called Smart Gas and Fire detector. The device can detect any spillage of gas and fire very quickly and send a response via gsm tool directly to the user very fast and a buzzer is set up to alert. The device also has another feature with an exhaust fan which will be activated in case of gas leakage and fire detected, to reduce the density of gas by pushing the air outside. The device is designed to detect gas and fire as quickly as possible. Its performance is the same in case of closed and open both types of room.

With a view to document the existing cropping patterns, cropping intensity and crop diversity, a study was carried out over all the upazilas of Bogra agricultural region during 2015-16. A pre-tested semi-structured questionnaire was properly used for this purpose. In the findings it was recorded that 21.88% of net cropped area (NCA) of the region was occupied by the cropping pattern Boro−Fallow−T. Aman. This pattern was found to be distributed over 27 upazilas out of 35. The second largest area, 13.26% of NCA, was covered by Potato−Boro−T. Aman, which was spread over 17 upazilas. A total of 177 cropping patterns were identified in the whole region in this investigation. The highest number of cropping patterns was identified 36 in Nandigram upazila and the lowest was six in Dupchachia and Kahalu upazila of Bogra district. The lowest crop diversity index (CDI) was reported 0.718 in Raiganj upazila of Sirajganj district followed by 0.734 in Kalai of Joypurhat. The highest value of CDI was observed 0.978 in Pabna sadar followed by 0.972 in Bera upazila. The range of cropping intensity values was recorded 183-291%. The maximum value was for Khetlal upazila of Joypurhat district and minimum for Bera of Pabna. As a whole the CDI of Bogra region was calculated 0.966 and the average cropping intensity at regional level was 234%.Bangladesh Rice j. 2017, 21(2): 73-90

Nanoelectronic devices emulating neuro-synaptic functionalities through their intrinsic physics at low operating energies are imperative toward the realization of brain-like neuromorphic computers. In this work, we leverage the non-linear voltage dependent partial polarization switching of a ferroelectric field effect transistor to mimic plasticity characteristics of biological synapses. We provide experimental measurements of the synaptic characteristics for a 28 nm high-k metal gate technology based device and develop an experimentally calibrated device model for large-scale system performance prediction. Decoupled read-write paths, ultra-low programming energies, and the possibility of arranging such devices in a cross-point architecture demonstrate the synaptic efficacy of the device. Our hardware-algorithm co-design analysis reveals that the intrinsic plasticity of the ferroelectric devices has potential to enable unsupervised local learning in edge devices with limited training data.

Finding proper design patterns has always been an important research topic in the software engineering community. One of the main responsibilities of the software developers is to determine which design pattern fits best to solve a particular problem. Design patterns support the effort of exploring the use of artificial intelligence in better management of software development and maintenance process by providing faster, less costly, smarter and on-time decisions (Pena-Mora & Vadhavkar, 1996). There has been a permanent interest in finding new design patterns, especially in the last two decades. Many new design patterns apply in various areas of computer science, such as software security, software parallelism, large-scale software evolving, artificial intelligence, and more. To the best of our knowledge, the “Obligation Link” and “History Reminder” design patterns are new and can be applied in software development in many areas of computer science including artificial intelligence.

As poor stability is the primary constraint for the commercialization of perovskite solar cells, improving stability has been the primary focus of recent research works regarding solar cells that make use of perovskite materials. Different metal oxide transport layers are being used with the aim of fabricating stable perovskite solar cells. A stable and efficient solar cell with both metal oxide transport layers (ZnO and N i O X ) and a perovskite (methyl ammonium lead iodide) absorber layer is simulated in this work, and a comparison of performance parameters is made with other transport layers from the literature. The issue of optimization regarding the thickness of the absorber layer and the doping concentration in the absorber and transport layers has been addressed, and the effect of defect concentration at the interface has been investigated. Optimum performance is achieved with an absorber layer of thickness 800 nm. Linear grading is also introduced in the absorber layer by varying the concentration of different halides, which increases the efficiency by approximately 8% owing to the increase in the short circuit current density.

Tunneling field effect transistor (TFET) is thought to be a successor in future nanotechnology because of its low SS and off current. Junctionless TFETs are easier to fabricate and possess no random dopant fluctuations. In this paper a new heterostructure based junctionless device has been proposed with unequal gates. The proposed device has been compared with Si based TFET and equal gate TFETs. High ON current, promising ION/IoFF ratio and low negative bias current has been demonstrated.

This paper presents the design and prototype implementation of USenSewer, an automated sewerage management system that uses Arduino microcontroller coupled with an ultrasonic sensor, a NRF module and a GSM module to automate the routine checkup and removal of drain blockage vital for the continuous waste water flow in the big cities. The proposed system consists of three main components; the blockage detection system which is placed inside the drain, the blockage removal system which is placed above the ground level and a control center which controls and coordinates the collection of waste materials placed by the first two components. Several pilot installations of the system in the city of Dhaka have shown that the proposed system significantly outperforms the state-of-the-art manual systems prevailing in the city from the scalability, flexibility and economic point of view.