bluuebunny/crossref_metadata_2025_split huggingface dataset:
The two-levels rectangular microstrip Yagi antenna for Wi-Fi application
Authors: Ismail N , Oktafiani F , Permana D 
Published: December 2019

Abstract
An antenna is the most important part of a wireless communication system. Wi-Fi has an omnidirectional radiation pattern that results in a limited range of emissions. Therefore, it needs an external antenna with a higher gain than the internal antenna. This research designs rectangular Yagi microstrip antenna with two-levels of directors which can work at 2.4 GHz frequency (Wi-Fi Application). The selection of material permittivity value and dimension setting is committed carefully in order to gain > 5 dB. At the time of simulation, optimization is performed by changing the dimension of driven, director, reflector, and distance between levels. The realization of the antenna is committed by using dielectric material with relative permittivity of 4.3. The antenna test results show a bandwidth gain of 7.98 dB, S11 parameter of -16.223 dB with a bidirectional radiation pattern. By selecting the material permittivity value and prudence in managing the antenna dimensions, it is proven to produce an antenna with target gain although the antenna only uses 1 branch and 2-levels of directors.
Complementary of quaternion method and Boole’s rule on IMU sensor to calculate orientation angle of Stewart Platform
Authors: Nurhakim A , Saputra H M , Ismail N 
Published: December 2019

Abstract
This paper discusses the complement of the Quaternion method and Boole’s rules on the IMU sensor aimed to calculate the orientation angle of the Stewart Platform. Orientation angle validity of The Stewart platform is very difficult to recognize by using manual measuring devices. Thus, it requires an IMU sensor to calculate the orientation angle. The IMU sensor consists of three types of sensors, namely the accelerometer, magnetometer, and gyroscope sensors. The Quaternion method is used to calculate the pitch and roll angle of the accelerometer sensor. It is also used to calculate the yaw angle of the magnetometer sensor. Boole’s rule is used to calculate the pitch, roll, and yaw angles of the sensor gyroscope. Moreover, the orientation angle of accelerometer and magnetometer is combined with the orientation angle of the gyroscope using complementary. The test is carried out in six repetitions with angular parameters: 5º, 10º, 15º, 20º, 25º, 30º. Overall, the pitch angle has an average value of error percentage of 2.31%, roll angle has an average value of error percentage of 1.98%, and yaw angle has an average value of error percentage of 1.63%. The measurement results of the orientation angle of the Stewart Platform using the IMU sensor shows that the complementary quaternion and Boole’s rule on the IMU sensor is quite feasible as measuring instruments for the orientation angel of the Stewart Platform.
Diversity technique evaluation for LTE high mobility user based on high altitude platform
Authors: Ridwan A M , Alfian R , Daniil H , Iskandar I , Hamidi E A Z 
Published: December 2019

Abstract
HAPS (High Altitude Platform Station) is an alternative technology of communication system that utilizes terrestrial and satellite systems. HAPS technology is located in the stratosphere layer with the height of 17-22 km above the earth’s surface. HAPS has some advantages, which are wide range area, communication ability on line of sight (LOS), and low propagation delay. In this paper we present the comparison between single HAPS system and two HAPS diversity technique. From simulation result, it is evident that using two HAPS as a diversity technique gives better performance than the single HAPS system, it is shown by how the two HAPS diversity technique requires less SNR than the single HAPS system, typically 3 dB less of SNR.
Heart rate monitoring system based on website
Authors: Hamidi E A Z , Effendi M R , Ramdani F 
Published: December 2019

Abstract
Heart rate monitoring system based on Internet of Things is a device to monitor the heart rates through the website. The prototype designed using a pulse heart sensor that is attached to the finger, the Wi-Fi ESP 8266 module read the sensors and displayed in the LCD and the data obtained can be sent to the website. The data is sent to the databases to find out the record that can be accessed any time using smartphone by opening a web that is already available. So, the users can find when data recorded from the results of testing that has been done. Testing was done by taking 10 samples with a comparison between prototype and oximetry as a control, and the results are not too significant.
The generator operating system automatically uses a motorized change over switch devices
Authors: Muliyati D , Bakri F , Umami I , Sumardani D , Ambarwulan D 
Published: December 2019

Abstract
This system is carried out using two power between the National Electricity Company (PLN) as the main power and the generator as backup power. This system uses 30KVA power capacity for PLN and 45KVA for generator set (genset). This system relies heavily on the crucial role of the motorized change over switch device because the automatic transfer system can run properly without collisions when using the backup power supply and when the main power supplies return. The results provided by the observations on two power experiments between the power of the PLN and the power of the generator when there is a blackout at the PLN. The automatically performance of motorized change over switch works has a range of pauses of 18 seconds to be able to power the genset capable of taking on the role of PLN to back up the Building. Furthermore, when the PLN power returns the power is held for 30 seconds by a motorized change the over switch. It ensures that the main power of the PLN reconnected.
The effect of temperature on energy transfer capacity by laser
Authors: Rahardjo I A , Wadjdi F 
Published: December 2019

Abstract
This study aims to obtain an overview of the effect of temperature on energy transfer capacity by laser which can later be used as one of the basic considerations for transferring electrical energy through air that is converted into the form of light until it is received by the receiver by comparing the transmitted power and power received. The research method uses an experimental method with the design of a laser and a photovoltaic cell as a receiver. The schematic experiment starts with setting up equipment. It is then treated with temperature changes as an effect on the laser. The results of the treatment were analysed so that conclusions were obtained. Based on the results of the study, it was found that the significance level of probability value’s calculation or the significance coefficient was 8.26E-30 which means it is smaller than the specified error rate / alpha (α) of 0.05. And if the coefficient F is uses, the value of the calculated coefficient F is 459.3736 which means it is greater than the F table 4.001191. In accordance with the provisions that apply in testing the hypothesis, it can be concluded that the null hypothesis (H_o) which states “No effect of temperature on output power” is rejected. This means that the evidence of results accepts the alternative hypothesis (H_1) which states “There is an influence of temperature on the output power”. The correlation of the effect of changes in temperature to output power gives the equation y=3E-10xˆ3-3E-08xˆ2+6E-07x+5E-05. So it can be concluded that temperature changes have an effect on output power.
Simple smart glasses based on microcontrollers as money detector of nominal and authenticity
Authors: Muhammad M , Yusro M , Yuliatmojo P 
Published: December 2019

Abstract
This study aims to make a detector for the nominal value and authenticity of money (rupiah currency). The working principle of this tool is as follows: UV LED function to provide lighting to objects (money). The light will circulate hidden colours in original money so that you can differentiate original or fake money (money whose authenticity is doubtful). The white LED provides lighting for the object, then the light is received by the TCS3200-DB colour sensor to read its Red, Green and Blue (RGB). Furthermore, the RGB value will be processed by Arduino Mega 2560 to be compared with the RGB values in the program. The mini DF-Player functions to play sound according to the sound that has been recorded with the program. Testing the system is done to determine the percentage of success of the system in distinguishing between original money and the authenticity of money is doubtful. Testing of 5 (five) nominal 2016 emission rupiah, namely 2,000-rupiah (60%), 10,000-rupiah (100%), 20,000-rupiah (80%), 50,000-rupiah (100%) and 100,000-rupiah (66%), so the average percentage of success of the tool is 81.2%.
Development of smart and safe-bags for children based on microcontroller
Authors: Baihaqi A , Djatmiko W , Yusro M 
Published: December 2019

Abstract
This study aims to develop smart and safe bag that children use to go to school. This bag can provide information about the bag’s weight and the location of the user via text messages (SMS). The bag is designed using several main electronic devices, namely the microcontroller (Arduino Mega2560 board), the buck adjustable IC LM2956 module, the 5 Kg load cell sensor, the Neo 6M-V2 GPS module and the 800L-SIM module. From the test results, this bag system can measure the bag weight of up to 5 Kg with measurement accuracy reaching around 0.3 Kg; can read the user’s position with the accuracy of the GPS position reading reaching around 25 meters, and can provide bag weight information and user’s position through SMS communication. This bag is also capable of working for around 8 hours using a rechargeable Li-Po-3S 1400mAH battery.
Depth control design and simulation of hybrid underwater glider
Authors: Latifah A , Fatimah D D S , Hakim B L , Chandrahadinata D 
Published: December 2019

Abstract
The hybrid underwater glider is a class from the autonomous underwater vehicle (AUV) that the concept of a buoyancy-engine to drive the vehicle sinking or to float are integrated and propeller propulsion systems for variable motion. This kind of vehicle has multi-functionality that enables to maneuver with glider and AUV mode so that it is an effective tool for oceanographic research. To represent the vehicle dynamic, the mathematical model base on the Newton–Euler approach is designed as a nonlinear equation that derives from forces and moment that acting from the vehicle design. For glider motion, buoyancy-engine and moving mass are coupled for working as an input controller actuator, and there is controlling need to make the vehicle go to mission point in some depth for a mission. In this paper, the depth controller will be designed to make the vehicle stay on depth condition. PID controller is used for controller design, that the mathematical model is derived to linear model. Simulation on MATLAB/Simulink is used to design the model and get dynamic vehicle response. With vehicle characteristic for glider motion, desired waypoint obtained with PD control for moving mass in x-axes and P controller for buoyancy engine.
The automatic battery charger based on floating technique
Authors: Mulyana E , Atmoko T D , Kamelia L 
Published: December 2019

Abstract
An automated system will simplify all the work done by humans. One of the automatic systems that has been used is the battery charger system that can be cut by itself. This paper discussed the implementation of automatic systems for battery chargers based on floating techniques. The system will automatically fill and repair the battery from several causes of damage such as overcharging the battery. This charger functions with the switch system turning on and off. The circuit works by comparing the input that goes into the IC, and makes the control input as the main standard of 1.10 V which is attached on a positive foot (pin3) on the IC. The main control system consists of Transistor BC547, IC LM358 and Transistor 2N2907A. This system also uses two transformers, each of which is used to support control and power supply. For the control section using 1A transformer and for power supply using 2A. This system will automatically switch on when the load level is below 12.27 V.
Double layer parasitic radiator for S-Band antennas to increase gain and bandwidth performances
Authors: Sandi E , Diamah A , Iqbal M W , Fajriah D N 
Published: December 2019

Abstract
In this paper, a parasitic radiator combination was developed to improve the gain performance and bandwidth of the S-Band frequency microstrip antenna. Previous studies focused on adding one side layer of the parasitic radiator and the same structure, so the idea emerged to develop a microstrip antenna by adding parasitic radiators from the two sides of the antenna radiator layer and the different structure of the parasitic structure. In this paper, the design of the parasitic radiator is added by combining the circular parasitic radiator patch on the upper layer of the antenna radiator and the square parasitic radiator patch on the bottom layer of the antenna radiator. This study uses a research and development approach through the calculation of parasitic radiator structure and setting the distance between layers. Next is the simulation design and fabrication of antenna samples to verify the test results. Simulation and measurement results show that by adding a parasitic combination of radiators with a distance of 0.36 λ_g at the top layer and 0.15 λ_g at the bottom layer of the antenna, a better gain and bandwidth performance improvement as compared to the addition of parasitic radiator designs in previous studies. This result confirms that the idea of adding a double layer parasitic radiator can be used to improve the performance of a microstrip antenna.
Direct and indirect measurement techniques of cavitation intensity: a brief review
Authors: Triawan F , Budiman B A , Nurprasetio I P , Sunnardianto G K 
Published: December 2019

Abstract
Cavitation has been one of the critical issues in turbomachinery operation which often causes the reduction of service life of the components. In order to predict the service life, cavitation intensity (CI) needs to be measured accurately. In this paper, several notable developments of techniques to measure CI are reviewed briefly. Those techniques can be classified into two groups, i.e. direct and indirect measurements. For the indirect technique, a method which estimates the impact load of bubble collapse by inverse analysis is particularly elaborated. For the direct technique, a method which utilizes painting technique to quantify the actual CI is specifically presented. The advantages and disadvantages of both direct and indirect techniques are also discussed.
Analysis of fire rate on paper coated with the silica gel from rice husk ash
Authors: Sutrisno H H , Wirawan R , Febriani A , Ambarwati D 
Published: December 2019

Abstract
Silica element can be used as one of additional elements in a material. It is good to improve the thermal properties so it can stabilize the heat resistance of a material. The silica gel resulted from the extraction process of rice husk ash can also do the stabilization of heat resistance. This element is known to be able to reduce the fire rate in a material. In this research, the fire rate on a paper is analyzed from the result of paper coating by using the silica resulted from the extraction of rice husk ash. It is done by using the flammability test device. The silica gel used to coat the paper is obtained from variety of time during the extraction process, so it will give a difference toward the fire rate on the paper. From the research result, the paper coated by the silica gel sourced from the extraction of rice husk ash with the shortest amount of heating time has the lowest fire rate compared to other samples. It means that the percentage of silica gel obtained from the extraction of rice hush ask with various time variety is in line with the reduction of fire rate.
The influence of engineering students numerical reasoning on the academic achievement of Computer Numerical Control (CNC) course
Authors: Dudung A , Nurhidayat D , Yuliatmojo P 
Published: December 2019

Abstract
The research aimed to examine the relationship between numerical reasoning abilities and academic achievement in CNC (Computer Numerical Control) course and the contribution of numerical reasoning of CNC course. This study employed a survey method with correlational causal relationships. The stratified random sampling proportional technique is employed with 30 engineering students. The results of the study show the significant relationship between numerical reasoning and academic achievement of CNC course with r count = 0.76. The two coefficients are terminated by independent variables (predictors of X) for changes in the dependent variable (Y criterion) of R square = 57.8%. The results show that there is a positive relationship between the two variables. Therefore, the learning experiences should provide the opportunities for students to develop their numerical reasoning.
How vocational high-school students understand geothermal energy
Authors: Wahyudi W , Pambudi N A , Biddinika M K , Basori B , Rudiyanto B 
Published: December 2019

Abstract
Indonesia has the highest potential of geothermal energy in the world with 28,5 GW. However, the utilization ratio is low with around 6% only. This situation occur since there are several geothermal energy targets failed to be achieved. The development of geothermal energy has several problems and one of them is rejection in the community when geothermal development begins. To overcome this situation, an increase in community understanding of this technology usage needs to be conducted. Therefore, the objective of this study is to discover public understanding by exploring the knowledge of vocational high school students about geothermal energy. This is conducted because they are young people who are part of the community. Their knowledge plays an important role in selecting energy sources for the country in the future. This study uses a triangulation strategy model that combines quantitative and qualitative methods. Respondents were students in Indonesia with a case study in Karanganyar Regency, Central of Java. Knowledge is measured by an indicator of the level of understanding of geothermal technology.
The influence of acid and base solutions on the quenching process against the hardness of ST37 steel
Authors: Akbar A , Firdaus R , Mulyadi M 
Published: December 2019

Abstract
Previous research stated that salt water cooling media has higher hardness value after going through the heat treatment process compared to freshwater cooling media. From this explanation, a study was conducted on the effect of using acid and alkaline solutions in the quenching process against the hardness of ST37 steel. This study uses vinegar water cooling media and soapy water. In this study several steps were carried out, namely: hardening on ST37 steel with a heating temperature of 700ºC with a holding time of 15 minutes, direct quenching with acidic cooling media (vinegar: 2.4 pH) and alkaline solution (soap water: 9.3 pH ) with a 15 minute holding time. After the heat treatment process and direct quenching on ST37 steel, Rockwell hardness was tested. From the test results, the use of acid and base solution cooling media in the quenching process has an effect on the hardness of ST37 steel, the best hardness value is an alkaline solution compared to an acid solution, alkaline solution has a hard value of 66.73 HRC, while acid solution has a hardness value of 64.31 HRC. The results of this study will be one of the references for further research, especially the use of weak acid-base solutions as a cooling medium.
Microwave absorbing characteristics in multilayer absorbers based on barium ferrite and teflon
Authors: Handoko E , Susila A B , Sugihartono I , Marpaung M A , Jalil Z , Alaydrus M 
Published: December 2019

Abstract
In order to investigate a new microwave absorbing characteristics of multilayer absorbers. Barium ferrite BaFe12O19 was synthesized by a standard ceramic method. Teflon was obtained from the china product and is available in the market. Multilayer absorbers based on 2 mm of barium ferrite layer thickness and 0.5 mm of teflon layer thickness with 2, 4, 6 and 10 layers were characterized by using vector network analyzer (VNA) Rohde-Schwarz ZVA 67 for 7.5 – 11.5 GHz frequencies. Reflection loss (RL) of multilayer absorbers were calculated and simulated using the transmit line theory. The microwave absorption abilities were enhanced for multilayer structure due to the combination of barium ferrite and teflon layers. The optimal absorption ability was achieved with − 20 dB (i.e. 99.9 % absorption) of reflection loss.
Energies of the static solitary wave solutions of the one-dimensional Gross-Pitaevskii equation
Authors: Prayitno T B , Budi E , Fahdiran R 
Published: December 2019

Abstract
We calculated the energies of the static solitary wave solutions of the one-dimensional Gross-Pitaevskii equation with the time-dependent parabolic trap, the time-dependent scattering wave length of s-wave, and the time-dependent external potential describing a gain or loss term. Some written solutions of the equation were used, two of which are based on the experimental results. The solutions satisfy the condition of solitary wave solution since they are localized over the space. By this argument, the energies were obtained by integrating the Hamiltonian density over the space formulated in the classical field theory. To do that, we constructed the appropriate Lagrangian density representing the equation by initially writing the ansatz Lagrangian density and then substituting into the Euler-Lagrange equation. We found that two of the solutions have the same energies and the other one should mathematically have the pure imaginary function describing the gain-loss term to achieve the real energy.
Ideal gas model of Bose-Einstein condensates confined in the parabolic trap
Authors: Prayitno T B , Budi E , Fahdiran R 
Published: December 2019

Abstract
By using the one-dimensional canonical partition function, we modelled an ideal gas-like form of a set of Bose-Einstein condensates confined by a three-dimensional anisotropic parabolic trap. The model itself was constructed by taking the eigenenergies of the one-dimensional Gross-Pitaevskii equation in the longitudinal direction and enabling the harmonic volume as the inverse cube of average geometric trapping frequency to substitute the real volume. In this paper, we showed that the condensates form an ideal gas represented by its equation of state and have similar mature to Einstein’s solid-like model with the corrections in both the low and high temperatures in the internal energy formulations.
PASSING for experiment tool in elasticity and hooke’s law concept on springs arranged in series and parallel
Authors: Suhendi H Y , Nurhasanah S , Yuningsih E K , Mulhayatiah D , Malik A 
Published: December 2019

Abstract
This study aims to analyze the feasibility of learning media PASSING (String Series Parallel) for concept elasticity and Hooke’s law. The method used in this study is ADDIE developed by Robert Marie Branch. The stages are Analysis, Design, Development, Implementation, and Evaluation. The steps of this study are: 1) Curriculum analysis, analysis of the results of interviews and questionnaires of students, and analysis of literature studies, 2) Designing learning media PASSING, 3) Realizing PASSING practicum tools 4) Performing expert validation tests 5) Product revisions. The results of the study obtained a tool validation value of 90.47% with a feasible category. This study concluded that PASSING is feasible to be used as a learning media in the concept of elasticity and Hooke’s law.