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The most common aid in assisting the visually-impaired person to move around is the white cane. However, the white cane has limitation in detecting head-level and trunk-level obstacles such as tables and tree branches. In this project, the Smart White Cane (SWC) is proposed. It is a retractable attachment device. It consists of Arduino microcontroller, piezoelectric sensor or buzzer, ultrasonic sensors, motion sensor and vibrating motors. The ultrasonic sensors play the role in detecting obstacles at head-level and trunk-level. At the end of the project, the SWC is built with the ability to detect head-level and trunk-level obstacles within 200 cm and 300 cm, respectively. However, the SWC still has limitations, such as unable to provide different alert outputs for the head-level and trunk-level obstacles, it needs to be lighter in weight and provides faster response time. [ABSTRACT FROM AUTHOR]

In this paper, technical and statistical analysis of Smart Living, one of the most important aspects of the next generation, has been provided with detailed information. Smart living refers to using technology and the internet of things (IoT) to pursue a more efficient, controllable, and productive lifestyle. In this century, with the increase in the global population, smart living is a significantly important criterion to ensure equal opportunities for all. Here a complete overview and case implementation are discussed, followed by an analysis of statistical data about the demand for smart living from a Techno-Socio point of view. Lastly, a few aspects and issues of Smart Living have been discussed, and a proposal is given to improvise it further for future research and possible implementation. [ABSTRACT FROM AUTHOR]

The photoelectrochemical performance of Ag coated CeO2 functionalized TiO2 nanotube arrays (AgCeTNT) is investigated here. The sample is prepared via three steps, such as synthesis of TiO2 nanotube by electrochemical anodization, CeO2 functionalization by hydrothermal and Ag coating by Successive Ionic Layer Adsorption and Reaction (SILAR) method. X-ray diffraction (XRD) analysis showed the anatase phase formation after annealing of TiO2 nanotubes. Field Emission Scanning Electron Microscopic (FESEM) images showed the conformal coverage of CeO2 and Ag nanoparticles on the surface of TiO2 nanotubes. Energy Dispersive X-Ray (EDX) analysis confirmed the presence of Ce, Ag, Ti and O in the AgCeTNT sample. Diffuse Reflectance Spectroscopy (DRS) study revealed the enhancement in visible light sensitivity with CeO2 functionalization and further with Ag coating. The photoelectrochemical measurement showed that the AgCeTNT sample exhibits improved photoelectrochemical performance compared to bare TiO2 nanotubes (TNT), CeO2 functionalized TiO2 nanotubes (CeTNT) and Ag coated TiO2 nanotubes (AgTNT) under the illumination of sunlight. This improvement in photoelectrochemical performance happeneddue to the combined effect of favorable band alignment of CeO2 and TiO2 and Surface Plasmon Resonance (SPR) effect of Ag nanoparticles, which lead to superior charge separation, efficient charge transport and enhanced visible light response. [ABSTRACT FROM AUTHOR]

Ultrathin g-C3N4 (g-CN) nanosheets are prepared by a two-step thermal exfoliation process in an air atmosphere. X-ray diffraction pattern (XRD) shows that ultrathin g-CN nanosheets have the same crystal structure as that of the bulk g-CN with a slight shift in the peak positions due to the reduction of sheet thickness. Field emission scanning electron microscope (FESEM) images show that the bulk g-CN is converted into ultrathin g-CN nanosheets due to thermal oxidation in an atmosphere, which increases the number of reactive active sites for water splitting. Due to a reduction in sheet thickness of g-CN, quantum confinement happened and thereby increase the bandgap from 2.88 (bulk g-CN) eV to 3.10 eV (ultrathin g-CN). Steady-state photoluminescence (PL) shows a blue shift, and time-resolve photoluminescence (TRPL) shows that the average lifetime of photogenerated charge carrier increases when bulk g-CN is converted into ultrathin g-CN nanosheets. Enhancement in photoelectrochemical performance is observed in ultrathin g-CN nanosheets compared to bulk g-CN due to the increased average lifetime of photogenerated charge carriers and a large number of reactive active sites. [ABSTRACT FROM AUTHOR]

The ordinary Portland cement (OPC) is the function as a binder for grout material. However, a massive used of OPC had caused pollution to the environment. Thus, the earlier research proposed the environmental friendly binder known as geopolymer. This new binder needs to be mixed between alkaline liquids and materials rich in silica and alumina. In this paper, fly ash class C was used as source material with alkaline activators such as sodium hydroxide (NaOH) and sodium silicate (Na2SiO3). This paper concluded that the concentration of NaOH solution and sodium silicate-to-sodium hydroxide (Na2SiO3/NaOH) ratios have a significant effect on compressive strength. The different concentration of NaOH solution (10 M and 12 M) and sodium silicate-to-sodium hydroxide (Na2SiO3/NaOH) ratios (1.5, 2.0, 2.5 and 3.0) were used in the production of geopolymer. The parameters such as curing and solid-to-liquid (S/L) ratio were controlled in this paper. The main evaluation techniques in this study were compressive strength and optical microscopy (OM). The optimum compressive strength obtained was 15.5 MPa for 28 days resulted from 12 M of NaOH concentration and Na2SiO3/NaOH with ratio 2.5. [ABSTRACT FROM AUTHOR]

Cognitive radio (CR) is the latest type of wireless technology and provides more flexibility in terms of spectrum utilization. in CR, secondary user uses primary user's spectrum during primary user's absence without interrupting the primary user's transmission. However, the secondary user's transmission is interrupted as primary user reconnects to their spectrum. The secondary user needs to identify a new available spectrum for retransmission. This paper presents the development of cognitive radio network using Android based smart phone for the data transmission. Both Bluetooth and WiFi spectrum detection are focused here. The used sensing method is energy based sensing method. The CR is developed using Java based Android Eclipse. The developed CR network is verified using Android based smart phone. Result shows that the proposed CR network is able to sense the spectrum with accuracy of approximately of 81%. The developed CR network is able to help secondary users to sense and use spectrum (licensed) for data transmission. [ABSTRACT FROM AUTHOR]

In Bangladesh, several gas turbine-based power plants often desynchronized from the national grid and remain in shutdown condition due to unstable grid frequency, lower electricity demand in the cold season, inclement weather etc. The main objective of this paper is to utilize those shutdown periods to lengthen off-line water wash cycle interval of gas turbines and to increase electricity generation. Two units of GE LM6000PC gas turbine has selected for this study. Since its initiation in 1998, the LM6000PC gas turbine has undergone a series of successful factory tests and several turbines have begun commercial operation. This paper provides an update of the LM6000PC performance and operating characteristics in Bangladesh, based upon data recorded in Max Power Limited's test facilities completed in 2018. It has found that a series of 3 hot water rinsing at 75-80 °C after every 120 hours of operation time can increase the water wash cycle interval by 33.3% of the original time. About 9% of energy has recovered that was lost due to the continuous running of a dirty compressor. The overall engine performance improved rapidly with hot water rinsing and yearly cost for water wash has reduced by 25%. [ABSTRACT FROM AUTHOR]

The fluid flow along the Riga plate with the influence of magnetic force in a rotating system has been investigated numerically. The governing equations have been derived from Navier-Stokes’ equations. Applying the boundary layer approximation, the appropriate boundary layer equations have been obtained. By using a usual transformation, the obtained governing equations have been transformed into a coupled dimensionless non-linear partial differential equation. The obtained dimensionless equations have been solved numerically by an explicit finite difference scheme. The simulated results have been obtained by using MATLAB R2015a. Also, the stability and convergence criteria have been analyzed. The effect of several parameters on the primary velocity, secondary velocity, temperature distributions as well as the local shear stress and the Nusselt number have been shown graphically. [ABSTRACT FROM AUTHOR]

Vanadium substituted TiO2 samples are prepared by modified sol-gel process. X-ray diffraction (XRD) pattern and Raman spectra for all the samples reveal pure tetragonal phases of TiO2. Rutile percentage calculated from XRD pattern and Raman spectra follow a similar trend and signify that vanadium substitution promotes phase transformation from anatase to rutile. Due to aliovalent V substitution, donor levels are formed in the bandgap which is responsible for bandgap reduction. [ABSTRACT FROM AUTHOR]

Ce0.975A0.025O2 (A=Co, Ni) was synthesized using sol-gel method. X-ray diffraction (XRD), UV-Vis and Raman spectroscopy are employed to evaluate structural, optoelectronic and vibrational properties of samples. XRD and Raman analysis confirms substitution of Co and Ni in CeO2 host matrix. It is observed that Co doping cause more strain and structural disorder than Ni doping in CeO2. This is also reflected from crystallite size of samples. A broad Raman band emerges at ~ 540-650 cm-1 indicating increase in oxygen vacancies with doping. X-ray absorption near edge structure (XANES) analysis estimates oxygen vacancies and valance state of Ce (Ce3+/Ce4+) in CeO2. [ABSTRACT FROM AUTHOR]

Vanadium substituted TiO2 samples are prepared by modified sol-gel process. X-ray diffraction (XRD) pattern and Raman spectra for all the samples reveal pure tetragonal phases of TiO2. Rutile percentage calculated from XRD pattern and Raman spectra follow a similar trend and signify that vanadium substitution promotes phase transformation from anatase to rutile. Due to aliovalent V substitution, donor levels are formed in the bandgap which is responsible for bandgap reduction. [ABSTRACT FROM AUTHOR]

Ce0.975A0.025O2 (A=Co, Ni) was synthesized using sol-gel method. X-ray diffraction (XRD), UV-Vis and Raman spectroscopy are employed to evaluate structural, optoelectronic and vibrational properties of samples. XRD and Raman analysis confirms substitution of Co and Ni in CeO2 host matrix. It is observed that Co doping cause more strain and structural disorder than Ni doping in CeO2. This is also reflected from crystallite size of samples. A broad Raman band emerges at ~ 540-650 cm-1 indicating increase in oxygen vacancies with doping. X-ray absorption near edge structure (XANES) analysis estimates oxygen vacancies and valance state of Ce (Ce3+/Ce4+) in CeO2. [ABSTRACT FROM AUTHOR]

A study of structure, morphology, and dielectric/complex impedance spectroscopy of lead-free 0.94(Na0.50Bi0.50)Ti0.95V0.05O3-0.06BaTiO3 ceramics, prepared by a modified sol-gel process, is explored. Rietveld refinement of x-ray diffraction confirmed the rhombohedralR3c phase. Temperature-dependent dielectric studies showed the antiferroelectric to paraelectric phase transition at a temperature, Tm~ 287 ºC.Complex impedance spectroscopy confirmed that the conductivity was found to increase from 1.8 × 10-8 Ω-1cm-1 (at 240 ºC) to ~2.6 × 10-5 Ω-1cm-1 (at 380 ºC) with increasing temperature. [ABSTRACT FROM AUTHOR]

The pure and V-Nd co-doped TiO2 samples are prepared by the modified sol-gel process. The phase formation is confirmed by XRD spectrum. Phase transformation is delayed in V-Nd co-doped TiO2 (TVN) samples compared to pure TiO2. The particle size is comparatively small in TVN samples at both the temperature 450 °C and 900 °C. Hence the effect of Nd doping is dominated over V doping in both phase transformation and grain growth process of TiO2. [ABSTRACT FROM AUTHOR]

The pure and V-Nd co-doped TiO2 samples are prepared by the modified sol-gel process. The phase formation is confirmed by XRD spectrum. Phase transformation is delayed in V-Nd co-doped TiO2 (TVN) samples compared to pure TiO2. The particle size is comparatively small in TVN samples at both the temperature 450 °C and 900 °C. Hence the effect of Nd doping is dominated over V doping in both phase transformation and grain growth process of TiO2. [ABSTRACT FROM AUTHOR]

Pulsating heat pipe (PHP) is a new innovation in the modern era of miniaturizes thermal management system for its higher heating and cooling capacity. The objective of this experiment is to observe the performance of open loop pulsating heat pipe using two fluids at different filling ratios. This OLPHP is a copper capillary tube of 2.5mm outer diameter and 2mm inner diameter. It consists of 8 loops where the evaporative section is 50mm, adiabatic section is 120mm and condensation section is 80mm. The experiment is conducted with distilled water and acetone at 40%, 50%, 60%, and 70% filling ratios where 0 (vertical) is considered as definite angle of inclination. Distilled water and acetone are selected as working fluids considering their different latent heat of vaporization and surface tension. It is found that acetone shows lower thermal resistance than water at all heat inputs. Best performance of acetone is attained at 70% filling ratio. Water displays better heat transfer capability at 50% filling ratio. [ABSTRACT FROM AUTHOR]

Organic ferroelectric crystals – diisopropylammonium bromide (DIPAB) and diisopropylammonium iodide (DIPAI) have been synthesized using different chemical methods. However the polarization values of these crystals are found comparable to that of inorganic ferroelectric materials. Monoclinic polar structure have been found for the crystals but the polarization and other electrical properties of DIPAB are much stable than those of DIPAI crystals. Hydroscopic nature of DIPAI crystals seems to be responsible for unstable electrical properties. [ABSTRACT FROM AUTHOR]