Dual solutions of magnetohydrodynamic stagnation point flow and heat transfer of viscoelastic nanofluid over a permeable stretching/shrinking sheet with thermal radiation

The present study is intended to encompass the stagnation point flow and heat transfer of viscoelastic nanofluid with the presence of thermal radiation. The viscous incompressible electrically conducting and Jeffrey fluid model is taken into account. The governing partial differential equations are reduced to ordinary differential equations by using the appropriate similarity variables. The resulting differential equations are solved numerically using the built in bvp4c function in Matlab. Dual solutions are discovered for a certain range of the governing parameters. Numerical results for the velocity and temperature profiles as well as the skin friction coefficients and the local Nusselt number are elucidated through tables and graphs

Microdistribution of Tin in Newly Synthesized Organotin(IV)-Treated Tropical Wood Cells

Penetration of wood preservatives into the wood cell is believed to be important to protect the wood from biodegradation especially fungal degradation. preservatives effectiveness depends on the amount of uptake or retention as well as its uniform distribution within the wood cells. Interest on organotin(IV) complexes both mono- and disubstituted organotin(IV) is increasing due to their interesting structural features, biocidal properties and environmentally friendly. The microdistribution of tin-based preservative in tropical woods was examined using Scanning Electron Microscope-Energy Dispersive X-ray (SEM-EDX) analyzer. Bulk specimens of 1% organotin(IV)-treated cubes were used to examine the microdistribution of tin in Alstonia scholaris, Macaranga triloba and Hevea brasiliensis woods. Conventional SEM-EDX was able to detect spatial distribution of tin in wood microstructure. The SEM-EDX distribution maps and linescan analyses showed that the deposition of tin were uneven with respect to cell microstructure in all woods studied with relatively higher tin accumulation in the ray cells and middle lamella than in the fibre cell wall. The results indicated that ray as the penetration pathway of organotin(IV) solution into the wood microstructure capable of penetrating the cell wall

Antioxidant properties of rice bran oil from different varieties extracted by solvent extraction methods

Antioxidant properties of rice bran oil from different rice bran varieties; Rice Bran-Bario (RB-Bario), Rice bran-Lowland (RB-Low) and Rice Bran- Upland rice (RB-Up), collected from different cultural plots, were assessed. Measurement of antioxidant properties was evaluated by TPC (total phenolic content), DPPH scavenging activities and reducing power of extracts.. The study shows that antioxidant efficacy of rice bran was found the highest in RB-Up, followed by RB- Low and RB-Bario. The antioxidant properties were related to the rice bran origin and water irrigation demand by particular variety. RB –Up has a unique plantation condition which takes least amount of water retention which contribute to the highest antioxidant activity. Extraction solvents used shows that Upland (16.15%) and Lowland (16.16%) yielded the highest amount in conserving the crude fat oil in rice bran extract compared to Bario

Non-Destructive Evaluation Of Selected Plantation Species

Non-destructive evaluation (NDE) of wood strength is getting great attention. By using NDE, in-situ wood strength can be determined without much sample preparation and more importantly without destroying the sample. This study attempted to employ NDE in wood by means of free-free flexural vibration. The dynamic moduli of elasticity were determined on (a) Hevea brasiliesis, (b) Acacia mangium and (c) Paraserianthes moluccana. Samples of size 10 (R) x 20 (T) x 340 mm (L) were prepared from tension and opposite wood of the intended species. For tension wood, the results of (a), (b) and (c) were 12.21, 14.45 and 6.71 GPa respectively. The results for opposite wood of (a), (b) and (c) were 11.84, 13.10 and 7.31 GPa respectively. Destructive tests were done on the same samples where modulus of elasticity (MOE) and modulus of rupture (MaR) were determined using threepoint bending. For species (a), the MOE values of tension and opposite wood were 10.76 and 9.42 GPa and the MaR values were 52.89 and 44.19 MPa respectively. For species (b), the MOE values were 12.64 and 11.52 GPa in tension and opposite wood respectively. For MaR, the results in tension and opposite wood were 110 and 96.98 MPa respectively. For species (c), the results for MOE values in tension and opposite wood were 5.68 and 6.53 GPa and those for MaR values were 34.69 and 41.02 MPa respectively

Radiation pattern reconfigurable fm antenna

In this work, a radiation pattern reconfigurable antenna design using compact printed spiral monopoles that operates at 102 MHz is reported. The proposed antenna changes its radiation behaviour that responds towards a desired direction with the use of RF switches. The antenna is printed on a 76.6mm × 50mm PCB layer providing more than 20MHz bandwidth at -10 dB threshold and is easily fabricated with low manufacturing cost. The antenna was also simulated on 500mm × 500mm ground plane that represents the roof top of a vehicl

Soil Properties under Various Stages of Secondary Forests at Sarawak, East Malaysia

Changes in the forest community during secondary succession are influencing in various soil properties. However, there is limited information available on the soil properties under different stages of secondary forests in Sarawak. The aims of this study are to clarify the soil morphological and physicochemical properties at secondary forests under different age stands after similar land change (slash and burn). Field surveys were conducted at 3, 5, 10, and 20 years old of secondary forests in Sabal, Sarawak. Different fallow time influence changing soil properties in various stage secondary forests. A number of soil properties affected soil development process and land use change. Soil morphological and physicochemical properties differed under different stages of fallow periods. The results showed that the soils under different stages of fallow lands after shifting cultivation in the study sites was categorized in acidic soil as indicated by pH (H2O) values of below than 5 and the low content of T-C and T-N as well as exchangeable bases. The close relationship can be assumed between soil development process and vegetation succession. The knowledge of forest soil properties is essential to understand the change and development process under various stages secondary forests. The comprehensive understanding about soil properties and development process is important in order to conserve and manage secondary forests

Soil Properties under Various Stages of Secondary Forests at Sarawak, East Malaysia

Change in the forest community during secondary succession is influencing in various soil properties. However, there is limited information available on the soil properties under different stages of secondary forests in Sarawak. The aims of this study are to clarify the soil morphological and physicochemical properties at secondary forests under different age stands after similar land change (slash and burn). Field surveys were conducted at 3, 5, 10, and 20 years old secondary forests in Sabal, Sarawak. Different fallow time influence changing soil properties in various stage secondary forests. A number of soil properties affected soil development process and land use change. Soil morphological and physicochemical properties differed and varied under different stages of fallow periods. The close relationship can be assumed between soil development process and vegetation succession. The knowledge of forest soil properties is essential to understand the change and development process under various stages secondary forests. The comprehensive understanding about soil properties and development process is important in order to conserve and manage secondary forests

Negative refraction metamaterial with low loss property at millimeter wave spectrum

The design of the millimetre-wave (MMW) metamaterials (MMs) unit cell operates at 28 GHz is presented and numerically investigated. The proposed structure composed of a modified split ring resonator (MSRR) printed on both sides of the substrate layer. Popular MM structures such as S-shape, G-shape, and Ω-shape are adjusted to operate at the 28 GHz for comparison purpose. MSRR achieves a wide bandwidth of 1.1 GHz in comparison with its counterparts at the resonance frequency. Moreover, the proposed structure presents very low losses by providing the highest transmission coefficient, S21, at the corresponding frequency region. The radiation loss is substantially suppressed and the negativity of the constitutive parameters of the proposed MM structure is maintained. By applying the principle of the electromagnetically induced transparency (EIT) phenomenon, the MSRR unit cell induces opposite currents on both sides of the substrate which leads to cancelling out the scattering fields and suppresses the radiation loss. The constitutive parameters of the MM structures are retrieved using well-known retrieval algorithm. The proposed structure can be used to enhance the performance of fifth-generation (5G) antenna such as the gain and bandwidth

Reliable early breast cancer detection using artificial neural network for small data set

This paper proposes a breast cancer detection module using Artificial Neural Network for small data set. The developed system consists of hardware and software. Hardware included UWB transceiver and a pair of home- made directional sensor/antenna. The software included a Graphical User Interface (GUI) and k-fold based feed-forward back propagation Neural Network module to detect the tumor existence, size and location along with soft interface between software and hardware. Forward scattering technique is used by placing two sensors diagonally opposite sides of a breast phantom. UWB pulses are transmitted from one side of phantom and received from other side, controlled by the software interface in PC environment. Firstly feed forward backpropagation neural network (FFBNN) is developed. Then, k-fold is combined with developed FFBNN for testing purpose. Four data sets are created where contains 125, 95, 65 and 30 data samples in 1st,2nd,3rd and 4th data set respectively. Collected received signals were then fed into the NN module for training, testing and validation. The process is done for all data sets separately. The system exhibits detection efficiency of tumor existence, location (x, y, z), and size were approximately 87.72%, 87.24%, 83.93% and 80.51% for 1st, 2nd, 3rd and 4th data set respectively. The proposed module is very practical with low-cost and user friendly. The developed breast cancer detection module can be used for large data samples as well as for minimum data samples