Data centers nowadays consume vast amounts of energy due to high density computational capabilities. Efficient energy consumption is a must to face the increased thermal dissipation of such modern data centers. Energy consumption can be addressed at multiple levels that include cooling requirements. Data center cooling represents a large portion of the energy consumed which can be minimized if best practices are applied in relation to the design of the data center. CFD simulations are the best tools to evaluate such practices in relation to the individual design of each data center. A simple raised floor data center was created using CFD software and two curtains were placed above the floor diffuser opening. The inlet air velocity was changed multiple times as well as the curtains heights. The results showed that: adding two curtains improves the temperature profile of the higher racks at the mid-plane, at low inlet velocities.

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Since from last decade, the lens antenna technology gained significant attention from researchers for various applications. Kinds of lenses introduced to enhance efficiency and gain regardless of end-user applications. The millimetre-wave beamspace communications are future communication technology introduced for improving the data rate and user capacity. However, the current solutions required the dedicated radio frequency channel which leads to extra overhead of energy consumption and cost efforts. Lens antenna technology has been proven an effective technique for Massive MIMO communications to improve the data rate and user capacity while achieving energy and spectral efficiency. In this paper, we present the scheme and experimental examination of the lens antenna based on Massive MIMO. The design of the lens antenna is performed by using the magnifying glass. The transceiver model of Massive MIMO consists of 60 lens antennas. This paper presents the complete design methodology of lens antenna for wireless communications and their experimental validations.

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Climate change affects the water cycle on the face of the earth which directly affects water availability. This study was conducted to identify the hazards of climate change to the water sector that are likely to occur in the Singkoyo Watershed. Some of the methods used include: Penman-Monteith method, calibration solver, F. J. Mock model, Mann Kendall and Sens (Makesens), relative distribution frequency (RDF) and weighting. The data used are secondary data, namely rainfall and climate of Singkoyo Station in the year 1986-2017. The results of the analysis of rain and climate data indicate that climate change has occurred in the Singkoyo Watershed. The hazard of decreasing water availability occurs in all projection periods with the weight of the hazards varying from the hazard of decreasing the availability of very high, high, medium and low water. The hazard of flooding does not occur this is seen from the decrease in the total runoff value (TRO) in the projected condition. While drought hazards occur in all projection periods with very high hazard weights due to a decrease in TRO = 120 mm/year, except for the period 2056 - 2065 there is a moderate drought hazard with hazard weight 3, where TRO reduction is 86.94 mm/year.

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In this work, two controllers, a Proportional Integral (PI) and a Model-based Predictive Controller (MPC), have been designed to regulate a DC/DC Buck-Boost converter. First, the modeling and linearization of the system was performed using a frequency response estimation method. Then the PI controller was designed around a certain setpoint. Next, an algorithm was designed according to the Extended Prediction Self-Adaptive Control (EPSAC). Finally, the performance of the controllers is evaluated for setpoint tracking and disturbance rejection.

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Microstrip Patch antennas are one of the biggest electronics markets being used in several industries and are responsible for many communication networks and systems. This project proposed to create a program using MATLAB to simulate a function that is similar to a high-frequency Microstrip Patch. The produced program was made from MATLAB with the aid of the antenna toolbox. Within this toolbox were custom antennas which means it was possible to create unique antenna geometry and meshes along with being able to determine the impedance needed. Antenna Toolbox and PDE Modeler is a function MATLAB contains commands for viewing the parameters when designing and analyzing MAPs.

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This geological structure estimation is done by flowing an electric current under the surface, then analyzing the different electrical resistance depending on the rock's quality, the degree of density, and soil moisture conditions. The research location is in East Kabaena, Bombana Regency, Southeast Sulawesi Province. The type of tool used is the G-Sound, a cheap and reliable resistivity (geoelectric) measurement tool. The geoelectric method used in this exploration is the resistivity method with the Schlumberger Method electrode configuration. Then the interpretation of the geoelectric survey data using the IP2Win software represents a sounding point. The results of field investigations found that the limonite layer with groundwater content had a resistivity value range of 0.28 -20.00 ohm-m. Then the limonite layer with a few chunks of rock with a resistivity value of 50.00 - 150 ohm-meters. The saprolite layer contains groundwater with a resistivity value of 100-200 ohm-m. The bedrock layer with a resistivity value greater than 5.034.00 - 23.351.00 ohm-m is the lowest part of the laterite profile. The nickel laterite is in the limonite and laterite layers with a resistivity value of 50.00 - 150 ohm-m with an estimated layer depth between 3 - 50 meters. The thickness of the layer ranges from 8 - 15 meters. Boring tests must accompany the use of geoelectric tools for the identification of soil structures. Interpretation of geoelectric data on metallic mineral resources includes the interpretation of geoelectric data into geological conditions.

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Surface Acoustic Wave (SAW) technology rapidly expands in modern sensing applications. Temperature, pressure and gases can be measured by SAW structure, configurable to be interrogated wirelessly. Presently, SAW sensor signal conditioning is mainly oriented to read the input-to-output phase difference by using analog circuits. Digital solutions are few (or not) explored, and its feasibility to process SAW signals in real conditions is unknown. This article studies two digital methods based on cross-correlation function and Fourier transform. Here is explained how good (or accurate) these methods read the phase difference when one of its input signals has considerable noise and attenuation, situation very common in SAW technology. This study has never been performed up to now and particular attention is given here to prove its feasibility. Our outcomes indicated that cross-correlation has better results than Fourier transform. In attenuation, cross-correlation reads the phase difference properly, but it is recommendable to apply smooth filtering when noise is significant. This function was developed by LabVIEW platform, whose noise and attenuation were included.

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In the world where collaboration among multidisciplinary services is necessary for continuous improvements, scientific computing, unfortunately, lacks the infrastructure that allows for this type of collaboration. As such, this paper recommends guidelines of service-oriented, multi-layered designs through the exemplifications of models, service-oriented architecture, architectural layers, service compositions, and computational stages. The objective is to apply these services-computing principles to the designs of scientific-computing applications. To establish the validity of these suggestions, further benchmarks that run on 32 computers have demonstrated consistent speedups of at least 20 times with negligible latencies in service orchestrations (under 1% of the total simulated time). This study provides sciences with procedures that coalesce with technologies through services computing platforms.

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Gardener conveys a wide range of plants which will have fluctuating watering requirements for each plant must get the perfect measure of water. An unreasonable measure of water may keep the plant's underlying foundations from oxygen and thought to process them to decay; too less water and the plant will now not get hold of the nutrients in wishes to keep on existing. Besides, gardener mostly do not know how was the character shown by plant instead of pets where they could show their feeling when they are threatening. This experiment concentrated on the best way to build up a framework utilising Arduino that controls all the parameter required of plants life at the ideal time. Besides that, this project proposed as no automation needed as we want it to be interactively fun like playing a "Pou" game for real in terms of plants.

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Performance analysis of Small Hydro Turbine is an essential practice to ensure that Small Hydro Plant performance is still at an acceptable level. In addition, performance testing is required as a part of programs to improve the efficiency, output, and economic performance of small hydro plants along with Optimization which has been an important focus in recent years. This study deals with three different Small Hydro Turbines of various manufacturer or projects. Comparison between simulation results and project/manufacturer data reveals a good agreement. To the best of the author’s knowledge these novel approach for CFD analysis of Small Hydro Turbines together using DSS Solidworks Flow Simulation (FloEFD) is absent in renewable energy or fluid mechanics literature due to its assessment complexity.

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The importance of the average reservoir pressure in all phases of the hydrocarbon industry implies to conduct continues research for better calculations of this property. In this paper the pseudo steady-state pressure solution in hydraulically fractured wells combined with a better determination of the effective wellbore radius is used to provide accurate estimations of the average reservoir pressure. These solutions initially presented for homogeneous formations are also extended to naturally fractured reservoirs and expressions for reservoir shape factors and average reservoir pressure are introduced for flow, pressure buildup and multi-rate tests for either liquids or gas reservoirs. The expressions are successfully tested with synthetic examples and compared to calculations from material balance given absolute deviation errors lower than 0.25 %.

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In Colombia, Battery Energy Storage Systems (BESS) is expected to be included in transmission and distribution power systems in the following years. In this paper, Quasi-Dynamic Simulations are performed to evaluate the BESS include impact in a Local Distribution System (LDS) lightly loaded. Simulation is performed in the IEEE 34 Node Test Feeder System modified with the Commercial and Industrial Colombian sectors demand curves. BESS operates during two peaks of load profiles. Voltages, Active and Reactive Power Levels are analyzed during a 24 hours period. Loading in transformers and distributions lines are analyzed too, in order to verify the electrical behavior during the operation of BESS. BESS do not increase considerably the voltage levels in the nodes but modify the active power pro-file during the peaks of the curves and change the reactive power levels in the LDS. The loading in lines and transformers have important changes. The Quasi-Dynamic simulation shows that is necessary include voltage regulators in a distribution system to keep the levels in the adequate range. In a distribution system lightly loaded the BESS cause small voltage changes in the nodes.

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In this work, two controllers, a Proportional Integral (PI) and a Model-based Predictive Controller (MPC), have been designed to regulate a DC/DC Boost converter. First, the modeling and linearization of the system was performed using a frequency response estimation method. Then the PI controller was designed around a certain setpoint. Next, an algorithm was designed according to the Extended Prediction Self-Adaptive Control (EPSAC). Finally, the performance of the controllers is evaluated for setpoint tracking and disturbance rejection.

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The prosthesis of hands in some of the cases allow to reach the same functionality that has a real hand. For this reason, in the development of this document we present a functional hand and forearm prosthesis, which allows providing a replacement option to those who, due to lack of development of this part of the body or an amputation, do not have this limb. To design this prototype, first some calculations of forces and torques that the proposed system can support are made. Then, with the support of a model designed in the software of Autodesk, simulations are found in which the design is subjected to external forces, giving as results the forces, deformations, tensions, among others, to which the prototype can operate.

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In this study, a new passive solar system-a sunspace in combination with solar chimney (SS)-is proposed to go well the challenges of energy demand in buildings. Renewable strategies for heating demand to be performed before regarding mechanical equipment. The SS system with an area of 4 m2 on the southern facet of the building is supposed. The simulation was conducted through the Energyplus software and validated by experimental data. Based on the outcomes, utilizing the SS system in buildings can increase the amount of heat gained. This is a practical plan to support space heating in wintry months. Furthermore, natural night ventilation over the SS can decrease the cooling load during warm seasons. The results additionally show that the highest energy-saving for heating and cooling observed in January and July respectively. Finally, the annual economic benefit of the SS system regarding the power saving will be 14.3% subsequently the extended charge for installing the SS will be regained by 8 years ordinarily.

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This paper presents a proposal for a Neuro-Fuzzy system to detect cancer-type Uveal Melanoma (UM). The proposed method integrates image processing algorithms with neuro-fuzzy system to detect the Uveal Melanoma. The results present the training process for two configurations of the neuro-fuzzy system. Rules that are redundant in the system could be identified and simplified. The model created using ANFIS provides a suitable system for the detection of Uveal Melanoma obtaining results close to 90.2% of accuracy.

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