This study examines the forced convective incompressible flow over a pair of side-by-side equal-sized circular cylinders confined in a rectangular channel in order to examine the influence of spacing on the heat transfer characteristics and the hydrodynamic force coefficients. Air with Prandtl number of 0.702 flows through the inlet at free stream temperature and velocity of T8 (=25oC) and U8(= 4.139m/s) respectively over the cylinders. The cylinder walls are at temperature Tw, where Tw>T8. The numerical study is carried out by solving continuity, momentum and energy equations using finite-element based software (COMSOL Multiphysics) at ReD = 2.35 x 104 and S/D = 1.1, 1.3, 2.0, 2.4, 3.0, 4.0 and 5.0. The results show that the drag and lift coefficients as well as the wake interactions depend strongly on spacing ratio. Biased flip-flop and anti-phase synchronised patterns were observed for the lift coefficients at S/D =2 and 3 respectively. At small spacing ratios S/D = 2, there is strong wake interaction between the cylinders whereas for S/D > 4, vortex structure interaction between the cylinders vanishes. Mean Nusselt numbers on the front, top, rear and bottom parts of the two cylinders are found to decrease as the S/D ratio increases. For all S/D, there are more isotherm contours on the front part than any other portions of the cylinders. This implies that the greatest heat transfer occurs on the front parts of the cylinders, and thereby flow interference on side-by-side structures is minimised at S/D > 2.

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Mobile Ad-Hoc Network (MANET) is an infrastructure-less network which has an ability to configure itself without any centralized management. The topology of MANET changes dynamically which make it open for new nodes to join it easily. The openness area of MANET makes it very vulnerable to different types of attacks. One of the most dangerous attacks is resource consumption attack (RCA). This type of attack, the attacker consumes the normal node energy by flooding it with bogus packets. Routing in MANET is susceptible to RCA and this is a crucial issue which deserves to be studied and solved. Therefore, the main objective of this paper is to study the impact of RCA on three routing protocols namely; Ad hoc On-Demand Distance Vector (AODV) and Dynamic Source Routing (DSR); as a try to find the most resistant routing protocol to such attack. The contribution of this paper is a new RCA model (RCAM) which applies RCA on the three chosen routing protocols using NS-2 simulator.

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Beam - column connection is a critical part of frame structure where it has to deal with different types of loads and transmit them. The beam-column connection effects on strength and serviceability of the structure should be taken into consideration throughout the design process. The beam-column connection has major roles in resisting lateral loads like earthquake, wind and blast. Undoubtedly, keeping joints sustain through these loads performing on a structure will protect human lives. For this specific reason, this research was carried out to investigate the beam-column connection by gathering the results from previous experimental researches. These researches have conducted an experimental trial on beam-column joint with different strengthen technique; such as ferrocement and carbon Fiber Reinforced Polymer, or using different types of stirrups like rectangle confining or spiral confining concrete. Theoretical analysis was operated using the finite element software, which is formulated considering the cyclic loading effects. The structural behavior under cyclic loading such as; energy dissipation capacity, stiffness degradation scalar, stress, good self-cantering, good ductility, compressive damage, tensile damage, displacements, equivalent plastic strain and plastic dissipation energy density were demonstrated. Comparisons with experimental results are performed to make sure that the finite element analysis is accurate. The parametric study in the next step will depend on evaluate parameters by calculating errors, accuracy, and predict its behavior by deep learning which considered to be advanced technology procedure of neural networks. In the end, the correlations between these parameters were presented as a prediction equation for parameters, and the best reinforcing details with minimum errors were proposed. For best details reinforcement from unconventional strengthen method was sample DCM- DOUBLE then DCM- SINGLE respectively, both show good handling for Damage dissipation energy density (DMENER), Magnitude of Plastic Strain (PEMAG) & Plastic Dissipation Energy Density (PENER), while for low Scaler Stiffness Degradation (SDEG) value samples (ND-T1 & ND-T2). Deep learning can be used to build equation connect all parameters with minimum error which improved by this research.

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In a set of experiments related to obtaining lipids from microalgae, a system was required that would automatically control some vital process variables (pH, temperature, wavelength and light/dark cycles) in the growth of such microorganisms. This article shows the design of such system, based on the emulation of a layered software architecture in the programming of a Programmable Logic Controller (PLC). Because this type of controller is exclusively programmed using logic blocks, the challenge of programming the PLC following a structured software architecture as the MVC (Model View Controller) pattern, was achieved. This allowed us for the improvement of the maintenance processes and simplified the addition of future modules. The system was successfully tested in a set of experiments, enabling several automatic tasks as: ease of control, continuous bioprocess monitoring, real-time data gathering, and evaluation of system status and execute corresponding system adjustments.

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The practical use of Alumina in various fields of engineering has become more in demand due to its properties to withstand high temperature, resist corrosion, and possess good hardness and strength. The synthesis of alumina nanoparticles is done by DC Thermal Plasma method where aluminum powder is flowed through oxygen gas to pass through arc in plasma torch so that primary particles are combusted and cause evaporation and crystallization to form alumina nanoparticles in particular phases. The XRD (X-Ray Diffraction) observation results showed variations in aluminum powder flow rate of 4.72, 5.90, 7.08 and 8.26 l/min with a processing time of 10, 20, 30, 40s. The alumina nanoparticles formed different dominant phases of ?-alumina and d-alumina phases with intensities above =75%. SEM (Scanning Electron Microscope) observations of the alumina nanoparticles was used to characterize the resulting particle diameter, morphology and structure. The powder flow rate variation of specific process times produced different agglomeration, mean size and structure of the resulting alumina nanomaterial.

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This research aims to find a best operating condition of a communal composter to process household solid waste to compost. 3 communal composters with a volume of 150 L and a diameter of 50 cm were used in this study. The composters have different operations including variation A with standard aeration and no stirring, variation B with standard aeration and stirring, and variation C with standard aeration, stirring, and blower for excess aeration. The compost activator used is Effective Microorganism (EM4), which is widely available in local market. Compost observations of 19-27 days resulting in temperature, pH, texture, colour, and odours complied with The Indonesian National Standard (SNI 19-7030-2004). Analysis on compost quality suggests that moisture content, C-organic, nitrogen, C/N ratio, phosphorus, and potassium fulfilled SNI 19-7030-2004. Quantity of compost result is in the range of 15-16 kg and the compost reduction is 48-51%. Scoring analysis suggests that composter with variation C displays the best performance on maturity, quality, and quantity.

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To improve the efficiency of irrigation water use and support increased food production, and in an effort to break the life cycle of Plant Disturbing Organism (PDO), it is necessary to adjust cropping patterns. Nowadays, monitoring and data collection on cropping patterns and paddy cultivation calendar can be done by applying remote sensing technology using satellite imagery and aerial imagery, for example, the Moderate Resolution Imaging Spectroradiometer (MODIS) image has a resolution of 250 meters. The purpose of this study was to identify cropping patterns of Cihea Irrigation Area in Cianjur Regency, West Java Province using MODIS imagery data for 2008 - 2018. The results showed in the Cihea Irrigation Area in Cianjur Regency, there are three growing seasons in one cultivation calendar year with a cropping pattern of twice paddy and one secondary crop (palawija) or mixed (paddy-palawija). The accuracy of the determination of crop types based on the analysis of NDVI data on MODIS imagery in first season (GS 1), second season (GS 2), and GS 3 were 80%, 80%, and 70% respectively.

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The addition of fibers to concrete has been of great interest in the field of materials science. The toughness of concrete mixes is affected by the material, geometric and amount of fiber used. Since different fiber produce different flexural behavior, it is necessary to conduct experimental test to determine the effects of fibers on mechanical properties of concrete. Therefore, in the present study is investigated the energy absorption capacity of hooked ends steel fiber reinforced concrete (0.3 and 0.9% volume fraction) against unreinforced concrete. Four different codes are used to evaluate the flexural toughness in all cases. The overall best results are obtained for the steel fiber–reinforced concrete with 0.90% volume fraction that depicted the largest toughness in comparison with the lower fiber proportion concrete mix (0.3% of vol.). In this concrete mix, the first-crack deflection was 0.06 mm, flexural toughness based on ASTM C1018 method starting from 5.1 up 32.2, and, flexural toughness values of 3.1, 1.06 and 71.6 for JSCE, Banthia and Trottier and ACI 544 methods, respectively. Experimental results also illustrated the beneficial effects of the steel fiber used to delaying the flexural strength peak in the strain hardening region.

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Generation of the electrical energy based on photovoltaic (PV) technology has been increased over the world due to either the continuous reduction in the traditional energy sources in addition to the pollution problems related to their usage, or the clean nature and safe usage of the PV technology. Also, PV systems can generate clean electricity in the site of using without any transmission which can be considered cost effective than other generation systems. The performance of the PV system is highly affected by the amount of solar radiation incident on it. Completely or partially shaded PV systems can affect its output. The PV system can be shaded by trees, buildings, dust, incorrect system configuration or other obstacles. The present paper studies the effect of the partial shading on the performance of a thin film PV module under climatic conditions of Cairo, Egypt. This effect was measured and evaluated according to practical measurement of the characteristic curves such as current-voltage and power-voltage for two identical PV modules (with and without shading) placed at the same time on one mechanical structure for comparison. The measurements have been carried out for the following shading patterns; half cell (bottom, middle and top of the PV module); complete cell; and two adjacent cells. For all shading patterns, the shapes of the I-V and P-V curves were changed and had more than one maximum power point. This problem can inversely affect the system in case of using traditional maximum power point trackers. Also, the output power from the module decreased according to the incomplete solar radiation reaching the PV module due to shadow patterns. The power loss due shading was 7%, 22% and 41% for shading of half-cell, one cell and two adjacent cells of the PV module, respectively.

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The oil and gas transmission pipelines used in the petrochemical industry are a very important asset but are in turn exposed to a very high risk due to the various threats to which they are subjected, one of these is third party damage to these pipelines, because the pipes suffer fracture or deformation that affect the integrity of the asset in mechanical characteristics such as strength and hardness among others and operational conditions such as fluid pressure and flow, causing deformations, leaks or in the worst case a break, delays in transport and therefore an increase in the costs of the same This is how the need arose to analyze the suitability for service according to API 579 by means of finite elements in a pipe with dent failure API 5L x70 of 42" diameter, belonging to a pipeline. To this end, the mechanical and operational conditions of the dent failure pipe were defined, the boundary conditions were established in a pipe model and finally the behavior of the pipe was resolved and analyzed by means of finite elements in a non-linear static regime.

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The Robellini Palm or Pygmy date palm is a species native to Laos. Reaching a maximum height of 5 meters, it is considered one of the most exotic and elegant palms in the world. In fact, according to the Colombian Ministry of Agriculture and Rural Development, in the Colombian department of Cundinamarca, approximately 5000 hectares have been planted with flowers and foliage, including this palm. As its main market is the United States, this palm is grown at high levels of quality, procuring, and the correct leaf length. However, this can be cumbersome for the farmers owing to the height of the plants. In this study, we aim to build a convolutional neural network (CNN) model that can help Robellini Palm farmers identify current plant growth stages through aerial photographs taken with drones. Therefore, crop images were collected and classified into the four stages identified by the grower (seedbed, sowing, development and cutting) with 230 images used to train the model designed. After different tests, the accuracy of the Robellini Palm growth stage identification system was determined to be between 85% and 90%. Hence, the designed CNN satisfactorily classified the images loaded from the different crop stages.

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Abstract:

Even though the world is well-advanced and fast-enough, cancer is still a life-threatening disease for every living being. The global mortality rate due to cancer is steadily increasing all days. In particular, breast cancer is the one which plays a major role in affecting human lives. Thus, a proper automated and computer-aided diagnosis tool is essential for the prediction of breast tumours. The paper aims to propose a hybridized algorithm that integrates Quadratic Discriminant Analysis (QDA) with Multi-Layer Perceptron (MLP) techniques. The idea behind the proposed algorithm is that the output of Quadratic Discriminant Analysis is cascaded with the Multi-Layer Perceptron network for the automatic classification of breast tumours. The paper utilizes the standard benchmark breast cancer dataset, Breast cancer wisconsin (diagnostic) dataset. The evaluated results are compared against the support vector machine, random forest, adaboost and Gaussian process classification algorithms. These comparisons are done through the calculation of confusion matrix elements. By using the elements of confusion matrix, several performance metrics are derived and used for the comparison of proposed classification algorithm with the existing ones. The paper exactly assesses the classification of tumour severity of breast cancer i.e. benign and malignant ones. The evaluated results show that the proposed hybrid algorithm is better in classifying the benign and malignant inputs than the existing algorithms.

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Abstract:

This research paper shows the utilization of image processing technique to calculate the distance and the size of an object. We call it LASERCAM, as it uses the laser beam technology. The proposed technique is based on the concept of image perspective in which one can observe that as the distance of an object from observer increases, the observer feels that the object is shortening. The primary logic for using the laser spots is to make its projection on the required object so that when the image is capture, the two spots also get captured in image frames so that the proposed method to calculate its distance and size can be implemented. The calculation of distance is based on the distance between the two spots at a specific distance. According to the theory of image perspective there is an inverse relation between distance from object and distance between laser spots, which is observed during the study as the distance increases from object, the distance between two laser spots decreases. The calculation of size is based on the numbers of pixel present between laser spots. The proposed method determined the length of specific number of pixels between laser spots and the known length is used to calculate the size of the object.

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