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Abstract. This study intended for the generation of hydroelectric power at suitable area of the strait in order to provide electric current to a close environment. The project uses a threedimensional model of taking flow into account the variation of hydrostatic pressure in the liquid vertical layers. We brought back to a two-dimensional calculation using the shallow water equations. The objectives of the study are getting simultaneous obtaining the velocities of currents by the component of velocities and distributions of the kinetic energy from the numerical results. The Bunaken strait is 5280 m width for an average depth of 130 m. Numerical calculation is simulated using horizontal meshes of 60 side meters. The numerical solutions obtained by using a time step of one second. It found that there was no great difference between 2D and 3D numerical simulations because the effect of flow velocity in the vertical direction is very small. The numerical results have shown that the average current velocities when low and high tide currents are 1.46 m/s and 0.85 m/s respectively. The kinetic energy ranged from 0.01 to 2.54 kW/m 2 when low and high tide in the Bunaken strait area at discharge of 1 Sv, whereas at discharge 2 Sv, 0.11-17.40 kW/m 2 and 0.11-2.77 kW/m 2 (when low and high tide currents). These results can used in the design of turbines for power generation marine currents in the Bunaken strait at depths below 60 meters. IntroductionConstruction of electrical power plants in Indonesia is urgently needed to overcome the shortage of electrical energy to date. One of the components for the construction of the power plant is marine current turbine [8,9]. Marine current turbine designs requiring variable of current velocity which is directly proportional to the kinetic energy. Many ways to get the data of current velocity, one way is by numerical model [2]. A numerical model of marine currents in Bunaken strait used a semi-implicit finite difference method for the numerical solution of three-dimensional shallow water flows. Several numerical methods with solution of shallow water equations used in practical applications [1,2,3,5]. Several existing numerical model for two and three dimensional shallow water flow simulations based on an alternating direction implicit ADI method. In semi-implicit method, only the barotropic pressure gradient in the momentum equations and the velocity divergence in the continuity equation taken implicitly. Each time step a linear five-diagonal system solved in new the water surface elevations for the entire domain are the unknowns. The model is generally explicit with the exception that the vertical eddy viscosity terms discretized implicitly. In the model formulation, the governing system of equations split into an external and an internal mode [2]. Momentum exchanges between vertical layers expressed in a set of tri-diagonal matrix equations relating the discrete horizontal velocities in each vertical level to the gradient of the water surface elevations [5].

Abstract.Manually recorded attendance of all the employees has produced some problems such as the data accuracy and staff performance efficiency. The objective of this research is to design and develop a software of RFID attendance system which is integrated with database system. This RFID attendance system was developed using several main components such as tags that will be used as a replacement of ID cards and a reader device that will read the information related to the employee attendance. The result of this project is a software of RFID attendance system that is integrated with the database and has a function to store the data or information of every single employee. This system has a maximum reading range of 2 cm with success probability of 1 and requires a minimum interval between readings of 2 seconds in order to achieve an optimal functionality. By using the system, the discipline attitude of the employees and also the performance of the staff will be improved instantly. IntroductionThe recording of employee attendance is one of the important factors in human resource management. In-depth and detailed information about an employee's presence can determine work performance, salary, productivity or agency progress in general. However, manually recording the attendance might cause some drawbacks namely time consuming and not being marked due to human error [1][2] [3]. RFID (Radio Frequency Identification) technology started to be developed as one of the alternative technology that makes it easy for users to identify for various things [4]. This technology itself consists of a tag in the form of a special chip where the chip has a unique code of information and a reader that serves to read the codes in the tag [4]. This technology has been implemented into several systems such as library management system, parking system [5] [6]. The use of RFID technology also has been used widely in such ways for automatic attendance system. In year 2016 and 2017, another student attendance monitoring system using a number of technologies has been presented [7][8]. The process of recording and reporting and employee attendance is a continuous process. Employees come at a certain time to attend the absence then at certain hours also the employee is doing absent return. At a certain times the administrative officer will take the attendance card and do the recapitulation to know the attendance number of an employee. Such a process would be very ineffective because it contains several weaknesses, therefore a system that can replace the process of data collection of employee attendance automatically and computerized with the help of RFID.To focus to the research, therefore this research has been limited to entry employee profile and attendance of the employee. With reference to the formulation of the above problem, the objective to be achieved in this research is to design an attendance system by using RFID technology that can help the

Abstract. One of equipment as prime movers in the marine current power plant is turbine. Marine current turbines require a data of marine currents velocity in its design. The objective of this study was to get the velocities distribution of marine currents in the Bangka strait. The method used survey, observation, and measurement in the Bangka strait. The data of seawater density conducted measurement in the Bangka strait. The data of width and depth of the strait collected from the map of Bangka strait and its depth of the sea. Problem solving of the study used a numerical model. The velocities distribution of marine current obtained from a numerical model in the form of numerical program. The results showed that the velocities distribution at seawater column when low and high tide currents which the maximum happened at 0.1 Sv were 0-0.9 and 0-1.0 m/s respectively, while at 0.3 Sv were 0-2.7 and 0-3.0 m/s respectively. The results will be a product in analyzing the potential kinetic energy that used to design profile of the turbines as prime mover for marine currents power plant in the Bangka strait, North Sulawesi, Indonesia.

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