A meta-analysis of studies evaluating the effect of porous pavements on surface hydrology. The analysis investigated experiments on infiltration rate and consequent runoff coefficient of porous pavements. Reviewed literature provided extensive indications on the benefits of porous pavements in mitigating hydrology in the built environment. It was demonstrated that previous pavements improved the hydrological properties of engineered surfaces including mitigating runoff and checking to flood. Accordingly, it was hypothesised that the mean effect among the selected studies is zero. A meta-analysis of selected experiments on porous pavements experiments established that the mean effect among the selected studies was zero. While the study adopted a methodology that included similar studies in terms of method, further study is recommended to control for the various factors that influence hydraulic properties of porous pavers mentioned in the conclusion of this study.

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Investigating the stress concentration in reinforced concrete connections under the blast loads is the purpose of the present paper. This goal was achieved by the design and analysis of the connections. The finite element package ABAQUS was used in this study to model and analyse the connections. A reinforced concrete connection which was tested experimentally was modelled and analysed in order to verify the modelling. The results of the modelling and experimental test were compared which demonstrated the accuracy of the modelling. Afterwards, two reinforced concrete buildings with five and nine storeys were designed employing the ETABS software. A beam-column connection of the ground floor of each building was designed. The sizes of the cross-sections of the beams and columns and the spaces of their stirrups were considered differently. These connections were also modelled and analysed. The distances of the connections from the blast centre were considered as 2.5 m, 5 m, and 10 m and the blast powers were adopted as 500 kg, 1000 kg, and 2000 kg TNT equivalent mass of explosive for the analyses of the connections. The stresses created in the reinforcements of the connections owing to the blast loads were examined. It was demonstrated that as the connection was located farther from the blast centre, the stresses in the connection reinforcements were reduced. Also, the stresses in the connection reinforcements were increased by enhancing the blast power. Meanwhile, using larger cross-sections for the beam and column in the connection of nine-storey building than the connection of five-storey building transferred the stress concentration in the reinforcements to the beam and near the beam-column connection. By decreasing the stirrups spaces of the beam in the connection of five-storey building, the high stresses in the reinforcements were mainly transferred to the beam of the connection which could reduce the likelihood of the progressive collapse of the structure.

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This paper represents the mathematical modeling, control design and simulation of grid connected single phase solar micro inverter. A system level approach is exploited to establish an upper-level block diagram that depicts the various blocks of the solar inverter. These blocks are PV panel, boost converter, inverter, ac grid and control system along with their coordination in power and signal flow. In mathematics modeling, complete state space model is developed, having three states of the system, magnetizing current, output voltage current and voltage. Photovoltaic voltage and duty ratio is taken as input to the state space model. A transfer function model between output ac voltage and input duty ratio is established and time domain analysis is conducted for its stability analysis. Frequency domain analysis is also carried out and a PI controller is designed to improve it relative stability. Feedback compensator and feed forward loop both are used to improve the system performance. The complete model along with its controller is developed in Simulink. Results of the model reveal the accurate operation of the inverter. DC rail output of the fly back converter produces 350V in steady state. In the startup phase of the inverter, it took 0.03 sec to synchronize the inverter output to the grid voltage. The peak voltage of the inverter is kept high than the grid voltage for the power injection to the grid. Safe mode operation of the inverter is tested by removing the grid intentionally and the inverter output voltage become zero.

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This study applied the measurement of dielectric properties and reflection coefficient by using Agilent E8362B slim probe. Slim probe and open-ended coaxial sensor are implemented to measure the dielectric properties and reflection coefficient of the cooking oil samples. The vegetable oils were purchased from the local market and were heated in the oven. Five types of cooking oil are corn oil, olive oil, palm oil; sunflower oil and walnut oil were measured at the temperature of 60°C, 80°C and 100°C for the frequency range of 0.2 GHz to 20GHz. As the oil, undergoes thermal degradation during heating, the chemical chain of oil will be altered and resulting in physical and internal properties change. Dielectric properties are part of physical-chemical properties of cooking oil that can be measured to inspect the oil quality. According to the dielectric properties and reflection coefficient measurement, there are different noticeable signal pattern which indicates the used and fresh cooking oil and the effect of heating period.

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The structure of Co80Sm20 thin films deposited on zirconium underlayer and without zirconium underlayer using dc magnetron sputtering technique was investigated based on selected area electron diffraction (SAED) in Transmission Electron Microscopy (TEM). The use of zirconium underlayer between magnetic thin film and Si (100) substrate increases the coercivity of the film by about two times compared to that for the film deposited directly on Si (100) substrate. The film deposited directly on a Si (100) substrate shows a larger loop squareness compared to that for the film deposited on zirconium underlayer. The high coercivity observed in the films deposited on thicker (100 nm) zirconium underlayer is discussed. X-Ray Diffraction (XRD) pattern shows no crystalline diffraction peaks from any of the Co80Sm20 thin film deposited on zirconium underlayer. Moreover, XRD result reveals preferred (10.0) and (00.2) orientation. Electron diffraction patterns reveal diffused rings for thicker zirconium undelayer. No diffraction peak from Co80Sm20 thin film can be observed from these electron diffraction patterns.

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The vegetable oil refining generates significant amounts of wastewater, which can be highly acidic, oily, and with significant organic matter loads. The objective of this paper is to show the development of a biocatalyst for the stimulation of native bacterial population in wastewater grease traps of a physical palm oil refining industry. The results suggest that BOD5 is the indicator parameter for evaluating the biostimulation efficiency in the wastewater pretreatment system (grease traps). On average, BOD5 removal efficiency is 21.4%. For the entire treatment system, BOD5 concentration of the final discharge during the biostimulation period is 1.38 times lower compared to the non-biostimulation period. The dynamic model developed to simulate the biostimulation system shows the following adjustment statistics: R2 = 92.5%, root-mean-square error = 164836 CFU and mean-absolute-percentage error = 13.3%. Dynamic simulation suggests that the growth and decay phases in the amount of total heterotrophic bacteria end at 15 and 67 days after the biocatalyst has been applied, respectively. Namely, the system stabilization phase starts at 68 days. The cost-effectiveness ratio of the biostimulation treatment system is 1.27 times lower compared to the non-biostimulation treatment system (physicochemical). The average annual economic savings with the biostimulation system is $12.5USD per ppm of BOD5 removed.

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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 Watkins-Johnson 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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This paper discusses the development system of IoT Controlled Hybrid Power Switching to provide consumer a system which allows them to manage their hybrid electricity sources. The generations of electricity can be produced by various of resources such as conventional and renewable resources. The existing method of generating electricity through renewable resources for instance a small scale of stand-alone solar photovoltaic system or pico-hydropower system gives consumers the ability to generate their own electricity source. In general, generated electricity from the resources is able to store in energy storage devices such as rechargeable lead-acid batteries. The main reason for generating electricity from renewable resources is that to reduce consumer dependence on depleting conventional resources at the same time they can experience monthly electricity bills saving. Without wasting the existed conventional resources, two different electricity generation can be combined thus creating a hybrid power system. The system is developed in order for consumers to consume both resources efficiently without producing any energy waste. The objectives development of IoT Controlled Hybrid Power Switching could help the consumer to manage both their electricity generation and consumption more effectively thus able to reduce their monthly electricity bills with more savings. This system provides flexibility for consumer to choose their options on how to consume electricity consumption. The available options are Auto-Mode and Manual-Mode. Both options using different methods consuming generated electricity. The Auto-Mode implementing an IoT element that provides consumers the ability to control electricity consumption through the Blynk application on smartphones. The switching between two sources is based on the percentage level of battery voltage capacity. For the Manual-Mode, the option gives the consumer the capability to control switching between two sources based on the time set by the consumer. Both options are able to deliver advantages to consumers in order to manage their electricity consumption dynamically.

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The one kilogram is the SI base unit of mass. It has been redefined on 20 May 2019 using an invariable natural constant. However, dissemination of the one kilogram still realizes through weighing traced to standard masses. Nevertheless, the NMIs will need to review and adjust their uncertainty budgets for measurements made after this date. This work describes dissemination of the mass unit for sub-multiple and multiples of the kg, reference masses and weighing design using for this dissemination. The traceability to the International Prototype one Kilogram is performed through, calibrating the one kilogram standard and using calibration design for the other weights associated with uncertainty calculation.

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In modern conditions, glass and glass products are becoming more and more demanded in various industries. At the same time, the industry makes more and more stringent requirements for the quality of products. This requirement forces glass manufacturers to improve production technologies aimed at improving the quality and reducing the cost of production. This research work is devoted to the sheet stack production technology modernization through the development and implementation of a high-precision distributed controller. The paper analyzes the existing system, synthesizes a regulator and performs mathematical modeling of the resulting system. This work can be useful both for the manufacturer of the sheet stack, and for specialists in the field of mathematical and computer modeling.

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There have been various studies on channel flow due to its relevance in engineering applications, but the effects of the entry conditions on the its flow characteristics have not be given much attention. This 2-D numerical simulation studied how the initial velocity and tripping devices at the entrance of a channel affect the mean flow structure. The CFD analysis is based on the use of COMSOL Multiphysics. The turbulent stresses in the RANS equation are closed using the k-? turbulence model. Input parameters for the simulation are taken from experimental conditions in the literature, with Reynolds number ranging from 18,700 to 600, 000. The CFD strategy flow without tripping is validated against experimental results and a good agreement is achieved. The results show that the skin friction factor for the flow without tripping for Reynolds number 18,700 is 3.59x10-3. However, for the same Re, with tripping devices covering 15%, 30%, 45%, and 60% of the channel height, the skin friction factors are 3.68x10-3, 3.78x10-3, 3.82x10-3, and 3.98x10-3 respectively. Hence it has been shown the tripping devices placed at the entry of a channel increase the skin friction coefficient by values between 2% to 11% for the various conditions considered in this work.

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Building facade inspection usually uses time-consuming, expensive data collection processes, with a risk level above the desirable, mainly because it is based on visual inspection. In this context, studies that address the acquisition of automated data and the post-processing of digital images have increasingly aroused researchers interest. In this work, we developed a low-cost system for identifying and classifying building facades pathologies formed by a drone for capturing high-resolution images and a web application containing three components: a) a set of machine learning and deep learning algorithms for the pathologies classification; b) a dataset of façade pathologies; c) an interface that allows an environment of interaction and selection of information that contributes to the user's decision-making process. To select the best method for identifying the type of pathology, we also performed a comparative analysis of algorithms effectiveness that uses decision trees, random forests, and convolutional neural networks. The results contribute to improving inspection processes on buildings facades and reducing costs and the risk of accidents.

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The physical, chemical and microbiological parameters of the water in the El Salado stream were determined, taking into account nine parameters: turbidity, dissolved oxygen, BOD5, pH, nitrates, phosphates, fecal coliforms, total solids and temperature in order to compare with the regulations, after which the Water Quality Index of the National Sanitation Foundation (ICA - NSF) of the United States was calculated; For this, four monitoring campaigns were carried out between the months of February, March, April and May 2019; at four sampling points. The results obtained show that the water quality is within the range of Bad to Medium.

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COVID-19 (corona virus disease 2019) a newly discovered virus that infects humans and is categorized as a global pandemic. Including in Indonesia, everyday case of COVID-19 increases and gets worse. In this digital era, we always use mobile smartphones every day to do our activities, that is why Traker choosesa mobile platform for development. Traker is a mobile application to trace and record the activity of an infected person, also to show any information about COVID-19 to the community as we proposed in Jakarta city. Traker works both on Android and iOS and Traker uses GPS method solution to track down the infected. The proposed model was designed using Unified Modeling Language (UML) such as a use case diagram for figure out the business process in the systems whilst a class diagram was used to design the database model. Android studio was used to implement the systems where each displayed user interfaces as a print screen of the running prototype application.

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Currently, mobile phones are one of the essential necessities that have everyday usage applications (apps). These are used for sending and receiving emails, watching pictures and movies, navigation, and much more. One of the most famous open-source mobile platforms is the Android which is installed on 79% of all new mobile devices. For the increase in usage of the Android operating system, security assurance of the user data is very important factor. The permission mechanism, required by the Android, requests for very sensitive permissions which are a matter of concern in most of the cases, but the user has to accept it to avail app installation. Now a day, researchers are focusing on the Android modification that includes the development of user-enhanced privacy over it. Many solutions are being proposed but with the flaw of reduced potential resulting from its modification. So it is required to develop such solutions where a user has the facility to review and edit permissions before the installation of an app. This paper provides a survey of permission-based security models and approaches for the Android operating system. The study also reveals and highlights the security issues of Android.

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The convolution integral is a linear operation. Invoking the linearity property, the superposition principle is applied in this paper to obtain the convolution integral between two signals. The method depends on dividing the two signals into several segments; each has a fixed function and a finite or infinite width. Depending on the product of the segments’ number of the first signal and that of the second signal, the evaluation of the convolution integral is divided into several sectors. Within each sector, one, two, or three integrals are needed to be calculated. The number of the integrals and the limits for each one depends on the width and the edge points of the two signals’ segments involved in a particular sector. After calculating all integrals, the superposition principle is applied to find the convolution integral for a specific period. The unit step function can be applied to express the convolution integral as a single expression.

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