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Performance evaluation and improvement of bankless channel
surface irrigation systems

Performance evaluation and improvement of bankless channel surface irrigation systems

The assumptions of a uniform depth and flow relationship inherent in the kinematic wave model render the model unsuitable for describing level basin systems. Basin systems are not free draining and the depth of flow/discharge relationship varies across a basin throughout an irrigation event compromising the operation of the kinematic wave model (Bassett et al., 1980). In contrast, both the zero-inertia and the volume balance models predict application times and the infiltrated volume equally well with the zero-inertia model superior at predicting advance in level basin systems (Badiger et al., 1997). For reliable solution, the zero-inertia model requires sub-critical flows (ie F r < 0.3) (Bassett et al., 1980). Sub-critical flow is typical in surface irrigation systems, only being exceeded immediately after the wetting front and slightly ahead of the recession front which, according to Bassett et al. (1980), contributes fewer errors than those generated by input and calculation anomalies. Furthermore, in non-draining level basin systems, the occurrence of super-critical flows is constrained to the advance front of the irrigation event, further reducing the potential for error. However, as the zero-inertia model cannot be solved directly for the cutoff time needed to satisfy an irrigation design requirement, the volume balance model is preferred for approximating design requirements.
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Hand Gestures Recognition Based on One Channel Surface EMG Signal

Hand Gestures Recognition Based on One Channel Surface EMG Signal

This paper focuses on the experiment where we plan to use EMG signals to recognize 2 hand gestures. And based on that, we are going to improve the ac- curacy of recognition by optimizing the algorithm. We plan to use the surface electromyography sensor (OpenBCI Ganglion) to capture muscle activity infor- mation on the skin surface of the corresponding muscle group. We are going to perform experiments to find the best placement of the electrodes and get the most reliable data. MATLAB is utilized for analyzing and processing the signals and for distinguishing the EMG generated by different gestures. The accuracy will be evaluated by performing additional tests.
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Performance evaluation and improvement of bankless channel
surface irrigation systems

Performance evaluation and improvement of bankless channel surface irrigation systems

Bankless Channel Irrigation Systems (BCISs) are a surface irrigation system composed of adjacent, terraced bays with an interconnecting channel constructed such that the rim of the channel is level with the floor of each adjoining bay. The mode of irrigation is similar to Drain Back Level Basins (DBLBs) where the accumulated surface storage of each upstream bay is used to augment flow to a downstream bay. The systems of this study have been adapted from rice-based layouts to incorporate furrows for row-cropping. It is this style of BCIS that has generated considerable interest in Australia, particularly in the south east, where the system is used to grow a variety of crops and offers considerable labour and machine efficiency savings. Two defining features of BCISs are a positive field slope which rises from the bankless channel, and the hydraulic interaction between adjoining bays during the recession phase of the upstream bay and the advance phase in the downstream bay. These two features make evaluation challenging and mean no available hydraulic simulation model can simulate irrigation in these systems across an entire field.
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Effects of hydroxyapatite nanostructure on channel surface of porcine acellular dermal matrix scaffold on cell viability and osteogenic differentiation of human periodontal ligament stem cells

Effects of hydroxyapatite nanostructure on channel surface of porcine acellular dermal matrix scaffold on cell viability and osteogenic differentiation of human periodontal ligament stem cells

Before being seeded on scaffolds, PDLSCs showed typical fibroblast-like morphology and expressed MSC markers CD44, CD73, CD90, CD105, and CD166. However, PDLSCs adopt a polygonal shape on HAp-PADM while those on pure PADM maintain their intrinsic spindle shapes under SEM. These results indicate that the surface and chemical composition characteristics of the scaffolds could influence the phenotype of cells. In fact, scaffold mean pore size significantly influences cell morphology and phenotypic expression. 16 By the assembly of HAp on PADM,
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LDA Study of Particulate Flow in a Channel with Deformed Surface Locations and with Flow Conditioner

LDA Study of Particulate Flow in a Channel with Deformed Surface Locations and with Flow Conditioner

Hydroabrasion in particulate flows plays an important role in various industrial and natural processes. To predict the effects of particulate flow and the resulting phenomena such as ero- sion/abrasion in a pipeline, channel or a fitting, it is essential to characterize the effects in a sim- ple standardized geometry. For this purpose, it is vital to initially understand the particulate flow behavior and motion in such geometries. In the present work, two series of experimental works by application of the LDA measurement technique were successfully conducted. First, the particulate flow behavior at downstream of a flow conditioner inside a channel with square cross-section was investigated. Shorter lengths for fully development of velocity profile by using the self-constructed flow conditioner were observed. Moreover, the flow at downstream of the conditioner was mod- eled with the CFD tool (ANSYS-CFX V. 14.57) and the simulation results were compared and vali- dated by the LDA experimental data. Better agreement between the simulation results and expe- rimental data was observed in the fully developed region. However, there are some deviations due to the actual pressure loss through the experimental loop and the calculated pressure loss value, which includes some assumptions for the loss coefficients. Furthermore, the particulate flow be- havior and vortex generation inside the deformed locations of a channel surface were studied in detail. With the help of the Matlab program, it was possible to calculate and visualize the velocity vectors for each measured point inside the channel accurately.
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EXPERIMENTAL INVESTIGATIONS OF HEAT TRANSFER ENHANCEMENT FROM DIMPLED SURFACE IN A CHANNEL

EXPERIMENTAL INVESTIGATIONS OF HEAT TRANSFER ENHANCEMENT FROM DIMPLED SURFACE IN A CHANNEL

et al. [8] describe the mechanisms responsible for local and spatially averaged heat transfer augmentations on flat channel surfaces with an array of dimples on one wall for one channel height, equal to 50% of the dimple print diameter. Other investigations consider flow and heat transfer in single spherical cavities [9]; effects of dimples and protrusions on opposite channel walls [4, 5]; the effects of dimple depth on vortex structure and surface heat transfer [11]; the effects of deep dimples on local surface Nusselt number distributions [2]; the combined influences of aspect ratio, temperature ratio, Reynolds number and flow structure [3]; and the flow structure due to dimple depressions on a channel surface [10].
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Finite Element Modelling of Biotransistors

Finite Element Modelling of Biotransistors

Abstract Current research efforts in biosensor design attempt to integrate biochemical assays with semiconduc- tor substrates and microfluidic assemblies to realize fully integrated lab-on-chip devices. The DNA biotransistor (BioFET) is an example of such a device. The process of chemical modification of the FET and attachment of linker and probe molecules is a statistical process that can result in variations in the sensed signal between different BioFET cells in an array. In order to quantify these and other variations and assess their importance in the design, com- plete physical simulation of the device is necessary. Here, we perform a mean-field finite-element modelling of a short channel, two-dimensional BioFET device. We com- pare the results of this model with one-dimensional cal- culation results to show important differences, illustrating the importance of the molecular structure, placement and conformation of DNA in determining the output signal. Keywords Biosensor Microarray DNA Model Sensitivity
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Thermal & Hydraulic Characteristics of Single phase flow in Mini-channel for Electronic cooling – Review

Thermal & Hydraulic Characteristics of Single phase flow in Mini-channel for Electronic cooling – Review

They give the reason for all three cases and source of error as well like, at low Reynolds numbers, the increase in temperature can be very large across a microchannel, causing a variable property effect. The large temperature gradient implies that the thermo-physical properties cannot be assumed as constant. This causes the bulk temperature of the fluid to vary in a non-linear form in the flow direction, which may cause deviations between experimental data and theoretical predictions the possible error that is often not taken into consideration is axial conduction. From all above Survey we come to know the importance of the non dimensional number like Re, Nu, Pr, Po and their physical interpretation. Type of fluid and fluid flow along with length of flow will help us to determine Convective heat transfer coefficient & also effect of inner surface roughness on pressure drop fluid flow and heat transfer. In mini channel range 200µm to 1 mm is very important to understand as per scaling law.
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The Thermal Effect of Variate Cross-Sectional Profile on Conformal Cooling Channels in Plastic Injection Moulding

The Thermal Effect of Variate Cross-Sectional Profile on Conformal Cooling Channels in Plastic Injection Moulding

For the case study, the industrial mould was adopted from previous study by Shayfull et al. [5] which consisted of two plate mould with submerged gating system for the front panel housing with dimensions of 120 mm x 80 mm x 18.75 mm and 2.5 mm thickness with a volume of 27663.64 mm3 was carefully chosen as the case study part for analysis (shown in Fig. 1). The size of selected part was able to accommodate with Sumitomo SH100A plastic injection moulding machine that available in production laboratory at Institut Kemahiran Tinggi Belia Abstract: Cooling system is an important role in designing a productive plastic injection moulding (PIM). The selection of geometry and layout for plastic injection moulding cooling channels strongly influences the cooling performance such as cooling time and thermal distribution that leads to shrinkage and warpage. This paper presents the study to determine the best cooling channel layout and cross-sectional profile which include circular straight drilled cooling channels, circular conformal cooling channels, square shape conformal cooling channels, elliptical conformal cooling channels and diamond conformal cooling channels. The cooling time and thermal distribution were simulated by Moldflow Insight (MFI) software. Results are presented based on ejection time and temperature variation by using transient analysis in MFI. The results found the best cross-sectional of cooling channels indicated by square shape conformal cooling channels, compare to others due to the shortest cooling time that recorded from simulation. The conformal cooling channel layout also resulted greater thermal distribution compared to straight drilled cooling channel design.
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Analysis of flow through rectangular mini channel with surface irregularities

Analysis of flow through rectangular mini channel with surface irregularities

Investigations on the flow and heat transfer behaviour of mini channels, both experimental and theoretical, have been compiled in many publications. While performing theoretical analysis, or using theoretical results to make comparisons with experimental results, often it is assumed that the channels possess regular geometrical shapes, with perfectly defined surfaces. In reality, the actual cross-sectional geometries produced by the fabrication techniques could be much different from these assumed perfect geometries, so that the assumption does not predict the performance correctly in an analysis. Single-phase convective heat transfer in a compact heat sink of hydraulic diameter 300 µm and depth 800 µm with relative roughness in the range 4–6% was investigated experimentally, by Shen et al. (2006). The friction factors and the local and average Nusselt number values were deviated significantly from theoretical predictions, depending on the surface roughness and the cross-sectional aspect ratio. Experimental investigation by Jiang et al. (1997) on the laminar flow of liquid in silicon micro channels with different cross-sections has shown that, for non-circular ducts, the values of C f & Re are smaller than predicted
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Sediment Yield and Soil Erosion Assessment by Using an Empirical Model of MPSIAC for Afjeh & Lavarak Sub-Watersheds, Iran

Sediment Yield and Soil Erosion Assessment by Using an Empirical Model of MPSIAC for Afjeh & Lavarak Sub-Watersheds, Iran

Abstract: Watershed degradation due to soil erosion and sedimentation is one of the major environmental problems in Iran. With respect to the relatively suitable compatibility of MPSIAC model to the arid and semiarid conditions of Iran and lack of hydrometric station in region, we employed the "modified PSIAC model" to estimating of sediment yield and providing sediment yield map in these sub-watersheds. The MPSIAC method incorporates nine environmental factors that contribute to sediment yield of the watershed, this factors are: surface geology, soil, climate, runoff, topography, ground cover, land use, channel and upland erosion. Open-source Geographic Information System (GIS) was used to facilitate the spatial interpola- tion of the nine model factors and interpretation of predicted sediment yield for the entire watersheds. At first, to enter the available raw data into the GIS framework we digitized the nine factors of maps. In the second stage, digitized maps were encoded with respect to the values of each factor and then these factors of maps were summed together, and finally sedi- mentation score map was provided. We applied (QS) equation on the sedimentation score map and finally related map was obtained. Various formations basically contain Shaly, Sandstone, Conglomerate and tuff lithology, covered this region more than igneous rocks. The results show that the most values of erosion are in Shaly, Marly, weathered Tuff and alluvial diposites parts of sub-watersheds correlated with sensitive formations such as Karaj and Quaternary sediments. Based on sediment yield map of MPSIAC model, more than 75% of the total sub-watersheds area was classified at class IV of erosion category with high sedimentation. Sub-basin’s erosion were calculated as 769.3 and 583.21 m2/km3 per year for each Afjeh and La- varak sub-basins by MPSIAC model, respectively. Linear regression analysis between MPSIAC model results and two of most influencing factors on erosion, the geology and soil erodibility indicated that there was a significant correlation. The results of this paper suggested that the model is suitable for predicting yearly average sediment yield of the Iranian water- sheds with similar conditions.
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Mutations causing Liddle syndrome reduce sodium dependent downregulation of the epithelial sodium channel in the Xenopus oocyte expression system

Mutations causing Liddle syndrome reduce sodium dependent downregulation of the epithelial sodium channel in the Xenopus oocyte expression system

Na 1 -dependent regulation of ENaC may require a sensor for Na 1 activity. This sensor could theoretically be either in ENaC itself or in another protein that would transmit the sig- nal by direct interaction with ENaC (e.g., ENaC binding pro- teins carrying WW-domains), or translate it into another sig- nal, e.g., a second messenger that would then act on ENaC. Whatever this mechanism may be, at some point it must re- quire the presence of an intact PY motif in both the b and the g subunits. The PY motifs are not only required for internal- ization, but also for the regulation of the current passing through each channel. Analyzing the mediators of the Na 1 - dependent regulation was not the focus of this study. How- ever, the experiments done in BAPTA- and EGTA-injected oocytes seem to indicate that intracellular calcium activity does not play a direct role in channel feedback regulation. In mouse mandibular duct cells, involvement of G proteins in regulation of a highly selective epithelial Na channel by [Na 1 ] i
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Report on the surface drift of the English Channel and neighbouring seas during 1897.

Report on the surface drift of the English Channel and neighbouring seas during 1897.

We conclude therefore that a wind exerting a horizontal pressure of 3'3 pounds per foot = a velocity of 26 miles per hour, or a force intermediate between 4 and 5, and blowing steadily [r]

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Study the Development and Operation of Discrete Vertical Drain Lateral-Diffused MOS (VDMOS) Power Transistors

Study the Development and Operation of Discrete Vertical Drain Lateral-Diffused MOS (VDMOS) Power Transistors

To expound two closely placed pn junctions at different depths below the silicon surface a vmosfet utilizes two successive diffusion steps. This dual diffusion technique can be used laterally in the same manner. The device structure called LDMOS. In this structure the channel length does not depend on the lithography step as in conventional lateral mosfets; rather it depends on the diffusion processes. Fig 4 shows the cross sectional view of LDMOS.

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Novel concept of multi-channel fiber optic surface plasmon resonance sensor

Novel concept of multi-channel fiber optic surface plasmon resonance sensor

Christos Themistos is an assistant professor at the Frederick Institute of Technology, Cyprus. His research interests are in the development of finite element based vectorial models in conjunction with perturbation technique for the analysis of surface plasmon modes in optical waveguides at optical and terahertz frequencies. He is also a visiting fellow at the photonics modeling group at City University, London.

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Novel concept of multi-channel fiber optic surface plasmon resonance sensor

Novel concept of multi-channel fiber optic surface plasmon resonance sensor

Permanent repository link: http://openaccess.city.ac.uk/14833/ Link to published version: http://dx.doi.org/10.1016/j.snb.2008.12.020 Copyright and reuse: City Research Online aims to ma[r]

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THERMAL PERFORMANCE IMPROVEMENT IN A SQUARE CHANNEL HEAT EXCHANGER WITH VARIOUS PARAMETERS OF V-WAVY PLATES

THERMAL PERFORMANCE IMPROVEMENT IN A SQUARE CHANNEL HEAT EXCHANGER WITH VARIOUS PARAMETERS OF V-WAVY PLATES

waviness aspect ratios (0.33, 0.42, and 51) with the diameter of the perforation of 5 mm and the width/height of the winglets of 5 mm. The Reynolds number in the range of 3900 to 11,400 was considered. They concluded that the maximum thermal enhancement factor is found to be around 1.26 at the lowest Reynolds number and at the highest waviness aspect ratio. Lotfi et al. (2016) investigated the thermo-hydraulic performance improvement in the wavy fin-and-elliptical tube heat exchanger combined with the new type vortex generator. The winglet was selected for their investigation to enhance the heat transfer rate and thermal performance of the wavy fin-and-tube heat exchanger. Du et al. (2014) and Du et al. (2013) selected the punched longitudinal vortex generator to increase the heat transfer rate of the wavy finned flat tube heat exchanger. They concluded that the average performance evaluation criteria or PEC can be up to 1.31 with six delta winglet pairs punched on the wavy fin surface. Song et al. (2015) presented the numerical investigation on heat transfer rate, pressure loss and thermal efficiency in the wavy fin channels of a compact heat exchanger. The effects of the channel space, wavelength ratio and amplitude ratio on
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Low Power and Simple Implementation of Secure Hashing Algorithm (SHA-2) using VHDL Implemented on FPGA of SHA-224/256 Core

Low Power and Simple Implementation of Secure Hashing Algorithm (SHA-2) using VHDL Implemented on FPGA of SHA-224/256 Core

In Channel shells, Nozzles are required for inlet and outlet purposes either to carry fluids or for providing multipurpose connections. If these nozzles present on peak of the dish end do not disturb the symmetry of the shell. However sometimes process requires that nozzles to be placed on the periphery of the shell. These nozzles disturb the symmetry of the shell. Geometrical parameters of nozzle connections may significantly vary even in one channel shell. These nozzles cause geometric discontinuity of the shell wall. So a stress concentration is created at the junction. Hence a detailed analysis is required. If nozzles are placed on the periphery of a channel shell, they disturb the axis symmetry of the system and cause eccentricity. Sometimes this cause generation of a couple & lead to a structural imbalance. So that it need to analysed in FEA to understand effects of nozzle on Stress attributes of the shell. This work also studies the effect of eccentricity of the nozzles under varying thickness of shell and reinforcement pad. The effect of material concession for nozzle and Shell on the stress induced is also studied. From the results obtained by ANSYS, optimum study was performed by response surface methodology to obtain optimum shell thickness and reinforcement pad thickness for different class of materials.
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4H-SiC Trench-Gate MOSFET: Practical Surface-Channel Mobility Extraction.

4H-SiC Trench-Gate MOSFET: Practical Surface-Channel Mobility Extraction.

The plasma-generated, reactive species, in addition to etching surface atoms, may also form non-volatile products which are deposited locally on surfaces creating a conformal film (which is the fundamental theory of PECVD). Fluorine plasmas can react with carbon atoms and be a major source of non-volatile fluorocarbon species. Under ion bombardment the non-volatile products may be sputtered, broken into smaller molecules, and/or react with the plasma, breaking down and forming volatile products (i.e. etched). It is commonly believed that non-volatile species which are sputtered or deposited on feature sidewalls assist in the anisotropic nature of RIE by inhibiting reactive plasma species from reaching the sidewalls. In summary, the RIE process effectiveness consists of an on-going balance between all these factors (plasma generated reactive species, chemical reactions, ion bombardment, non-volatile deposition, sputtering, and exhausting volatiles).
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The interaction between fluid flow and ultra-hydrophobic surface in mini channel

The interaction between fluid flow and ultra-hydrophobic surface in mini channel

The difference in the intensities of pixels over the line is well determined. The thickness of the air film was calculated against the position of the surface. The values of air film was correlated to the Re number of liquid flow. The results are seen in the Fig. 4. The PCB sample covered with UED ® nanoparticles is present as a reference sample. This sample has the surface roughness close to the stainless steel samples K-KAN-C with Ra 2.0, and K-KAN-D with Ra 2.2. This chart proves the dependence of the air film thickness on the surface roughness and it is not important, if the roughness is initial, ie. it is a material property, or it is developed due the covering process. This proof also corresponds with the theory of ultra-hydrophobicity on the rough defined surfaces. [5]
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