bluuebunny/crossref_metadata_2025 huggingface dataset:
Bayesian reconstruction of gravitational-wave signals from binary black holes with nonzero eccentricities
Authors: Dálya Gergely , Raffai Peter , Bécsy Bence
Published: December 2020

We present a comprehensive study on how well gravitational-wave signals of binary black holes (BBHs) with nonzero eccentricities can be recovered with state of the art model-independent waveform reconstruction and parameter estimation techniques. For this we use BayesWave, a Bayesian algorithm used by the LIGO–Virgo Collaboration for unmodeled reconstructions of signal waveforms and parameters. We used two different waveform models to produce simulated signals of BBHs with eccentric orbits and embed them in samples of simulated noise of design-sensitivity Advanced LIGO detectors. We studied the network overlaps and point estimates of central moments of signal waveforms recovered by BayesWave as a function of e, the eccentricity of the binary at 8 Hz orbital frequency. BayesWave recovers signals of near-circular (e ≲ 0.2) and highly eccentric (e ≳ 0.7) binaries with network overlaps similar to that of circular (e = 0) ones, however it produces lower network overlaps for binaries with e ∈ [0.2, 0.7]. Estimation errors on central frequencies and bandwidths (measured relative to bandwidths) are nearly independent from e, while estimation errors on central times and durations (measured relative to durations) increase and decrease with e above e ≳ 0.5, respectively. We also tested how BayesWave performs when reconstructions are carried out using generalized wavelets with linear frequency evolution (chirplets) instead of sine-Gaussian wavelets. We have found that network overlaps improve by ∼10–20 percent when chirplets are used, and the improvement is the highest at low (e < 0.5) eccentricities. There is however no significant change in the estimation errors of central moments when the chirplet base is used.
The interior inverse electromagnetic scattering for an inhomogeneous cavity
Authors: Zeng Fang , Meng Shixu
Published: December 2020

In this paper we consider the inverse electromagnetic scattering for a cavity surrounded by an inhomogeneous medium in three dimensions. The measurements are scattered electric fields measured on some surface inside the cavity, where such scattered electric fields are due to electric dipoles emitted on the same surface. By making use of a boundary value problem called the exterior transmission problem, we first prove that the measurements can uniquely determine the shape of the cavity. Then we apply the linear sampling method to reconstruct the cavity. Numerical examples are further provided to illustrate the viability of our algorithm.
A novel framework using gated recurrent unit for fault diagnosis of rotary machinery with noisy labels
Authors: Nie Xiaoyin , Xie Gang
Published: December 2020

Due to the harsh working environment, rotary machinery is susceptible to various faults, thus fault diagnosis to ensure safe operation is extremely important. Deep learning technology-based fault diagnosis is an effective method but may face the following limitations. With the complexity of labeling fault signals and limitation of labeling experience, noisy labels are likely to be introduced, which affects the diagnosis result. So a framework called GRUS-CL is proposed, in which a baseline network combining a gated recurrent unit and softmax (GRUS) is trained by minimizing the correction loss (CL). First, two-dimensional transformation is proposed to form two-dimensional samples with less calculation time. Second, GRUS is designed to extract features and diagnose automatically. Third, an adaptive balance factor is introduced to form CL. The proposed GRUS-CL is evaluated with a bearing dataset and achieves the advantages of excellent diagnosis effect, simple structure, high noisy label tolerance, and discriminative feature extraction.
A measuring method for layered compactness of loess subgrade based on hydraulic compaction
Authors: Zhang Zhipeng , Zhou Zhijun , Guo Tao , Xu Tianyu , Zhu Linxuan , Xu Fu , Chen Chaoran , Liu Tong
Published: December 2020

Subgrade compactness is a key factor determining subgrade quality. However, defects exist in the traditional methods for subgrade compactness measurement. Based on the theoretical analysis of dynamic impact and vibration waves, the hydraulic compaction method was used to measure the layered compactness of loess subgrade in this paper. A full-scale test was then carried out to observe the variation of soil parameters after hydraulic compaction. The results show that the layered interface settlement (LIS) of subgrade has the characteristic of stage change bounded by 0.9 m of depth and 6–9 blow times respectively. The compaction effect is not obvious when the depth exceeds 1.2 m, and thus the improvement depth was introduced. The settlement curve has the characteristic of the Boltzmann function. The relationship between layered compacted compactness and LIS was obtained by the regression method. Finally, based on the theory of layered compaction, a measuring method for the layered compactness of loess subgrade based on hydraulic compaction was presented. The field application demonstrates that the results of the hydraulic compaction method correspond well with that of the sand-filling method.
Insights into the green doping of clinoptilolite with Na+ ions (Na+/Clino) as a nanocatalyst in the conversion of palm oil into biodiesel; optimization and mechanism
Authors: Abukhadra Mostafa R , Basyouny Mohamed Gameel , El-Sherbeeny Ahmed M , El-Meligy Mohammed A , Luqman Monis
Published: December 2020

The critical demand for eco-friendly, renewable, and safe energy resources is an essential issue encountered in the contemporary world. The catalytic transesterification of plant oils into biodiesel was assessed as promising a technique for providing new forms of clean and safe fuel. Natural clinoptilolite was doped with Na+ ions by green chemical reactions between sodium nitrite and green tea extract, producing a novel modified structure (Na+/Clino). The Na+/Clino product had an enhanced total basicity (6.41 mmol OH/g), ion exchange capacity (387 meq/100 g), and surface area (312.7 m2 g−1), which qualified it to be used as a potential basic catalyst for the transesterification of palm oil. Transesterification tests were statistically assessed using a response surface methodology and a central composite design. Considering the effect of how the significant factors interact with each other, the synthetic Na+/Clino achieved a 96.4% experimental biodiesel yield after 70 min at 100 °C in the presence of 2.75 wt% catalyst loading and a 12.5:1 methanol-to-palm-oil ratio. Based on the optimization function of the statistical model, the performance of Na+/Clino can theoretically be enhanced to increase the yield to 98.2% by expanding the test time to 85 min and the loading value to 3 wt%. The product yielded by the Na+/ClinO process is of adequate technical properties, considering the international levels for standard biodiesel (EN 14214 and ASTM D-6751). Finally, the prepared green Na+ doped clinoptilolite had excellent recyclability as a heterogeneous basic catalyst and displayed higher efficiency than several species of previously studied heterogeneous and homogenous catalysts.
Dually acid- and GSH-triggered bis(β-cyclodextrin) as drugs delivery nanoplatform for effective anticancer monotherapy
Authors: Chen Jian , Liu Hui , Li Xiufang , Li Jianbing , Tang Rongdi , Deng Zhiwei , Yang Yanjing , Zhong Shian
Published: December 2020

The intrinsic poor solubility and limited load capacity of β-cyclodextrins (β-CDs) results in reduced bioavailability, rendering the material unsuitable in complex biological environments. In this work, a pair of β-CDs was methylated and covalently linked with acid-sensitive acylhydrazone and GSH-sensitive disulfide bonds to ensure a precise drug release pattern. The hydrophobic anticancer drug doxorubicin (Dox) was encapsulated inside the hydrophobic core of bis(β-CD) via hydrophobic association with loading capacity of 24% in weight and a hydrodynamic size of about 100 nm. When exposed to acidic and reductive environments, the acylhydrazone and disulfide bonds were found to be cleaved, resulting in Dox release. Using fluorescence imaging and flow cytometry analysis, the designed bis(β-CD) were determined to activate the drug release behavior by specific intracellular stimuli (pH and GSH). In vivo studies demonstrated specific drug delivery characteristics and controlled drug release behaviors in the tumor sites, giving rise to high antitumor activity and low toxicity. Taken in concert, this dual stimuli-responsive bis(β-CD) with superior amphiphilicity and biocompatibility features showed great potential for future clinical applications.
A reinforcement learning approach to rare trajectory sampling
Authors: Rose Dominic C , Mair Jamie F , Garrahan Juan P
Published: December 2020

Very often when studying non-equilibrium systems one is interested in analysing dynamical behaviour that occurs with very low probability, so called rare events. In practice, since rare events are by definition atypical, they are often difficult to access in a statistically significant way. What are required are strategies to ‘make rare events typical’ so that they can be generated on demand. Here we present such a general approach to adaptively construct a dynamics that efficiently samples atypical events. We do so by exploiting the methods of reinforcement learning (RL), which refers to the set of machine learning techniques aimed at finding the optimal behaviour to maximise a reward associated with the dynamics. We consider the general perspective of dynamical trajectory ensembles, whereby rare events are described in terms of ensemble reweighting. By minimising the distance between a reweighted ensemble and that of a suitably parametrised controlled dynamics we arrive at a set of methods similar to those of RL to numerically approximate the optimal dynamics that realises the rare behaviour of interest. As simple illustrations we consider in detail the problem of excursions of a random walker, for the case of rare events with a finite time horizon; and the problem of a studying current statistics of a particle hopping in a ring geometry, for the case of an infinite time horizon. We discuss natural extensions of the ideas presented here, including to continuous-time Markov systems, first passage time problems and non-Markovian dynamics.
Spatially resolved measurements of RF accelerated deuterons at JET
Authors: Sahlberg A. , Eriksson J. , Conroy S. , Ericsson G. , Nocente M. , Kazakov Ye.O. , JET Contributors
Published: December 2020

An understanding of fast (supra-thermal) ion behavior is of great importance in tokamak physics and is a subject studied from both theoretical and experimental perspectives. This paper investigates the spatial energy and density distributions of RF accelerated deuterons using the neutron camera at the tokamak JET. Using the 19 liquid scintillator detectors available in the neutron camera system, we obtain spatial information that cannot be accessed with a single sightline. We present a spectroscopic analysis method in which a spatially resolved model of the fast ion distribution is fitted to the pulse height spectra from all 19 detectors simultaneously. The fast ion distribution is parameterized in such a way that the density, energy, and pitch-angle parts are uncoupled. The energy part is composed of a Maxwellian distribution, characterized by an ‘RF tail temperature,’ and the spatial dependence is modeled as a two-dimensional Gaussian distribution on the poloidal plane of the tokamak. From this parameterized model, we can calculate the spectrum of fusion born neutrons originating from reactions involving RF accelerated deuterons, and by fitting this model to the measured neutron camera pulse height spectra, we obtain an estimate of the spatially resolved distribution of the fast deuterons. The method has been applied to three JET pulses using different RF heating schemes and is shown to identify several features of the fast ion distribution produced in the various scenarios. Hence, this method is able to provide quantitative information about the fast ion distribution resulting from different heating schemes, and can also be useful, e.g., to validate simulation results from RF modeling codes.
Linear MHD analyses of locked-mode-like instabilities in LHD
Authors: Okamoto M. , Tomita H. , Watanabe K.Y. , Sato M. , Takemura Y. , Sakakibara S. , Ida K. , Yoshinuma M. , LHD Experiment Group
Published: December 2020

To investigate the driving mechanism of the locked-mode-like instability observed in the large helical device, we reconstruct the magnetohydrodynamic (MHD) equilibria consistent with the measurement and identify a dominant MHD instability in the precursor phase based on linear MHD analyses. From the dependence of the linear growth rate on the magnetic Reynolds number, the radial mode structure of the electrostatic potential fluctuation and other indices, the ideal interchange mode is found to be dominant. Moreover, it is found that the Mercier parameter, D
I, becomes much larger than 0.3 during the phase, while the precursor has constant frequency and fluctuation amplitude. Therefore, D
I ≫ 0.3 is a good index of the on-set condition of the minor collapse itself. It is also found that the achievement of D
I ≫ 0.3 is due to the movement of the resonant surface to the inner plasma region, which corresponds to the larger pressure gradient region.
3rd International Conference on Vocational Education of Mechanical and Automotive Technology (ICoVEMAT) 2020
Authors: Siswanto I , Arifin Z , Nuryanto A , Pratiwi H , Efendi Y
Published: December 2020

The 3rd ICoVEMAT-2020 was organized by the Department of Mechanical Engineering Education and the Department of Automotive Engineering Education, Faculty of Engineering, Universitas Negeri Yogyakarta. It was successfully held on October 5th, 2020 using an online platform (zoom) due to the serious pandemic Covid 19 which is endangering people, leaving them no choice but to avoid gathering people at the same place.

The Third International Conference on Vocational Education of Mechanical and Automotive Technology (ICoVEMAT) 2020 aims to provide a platform for educators, academicians, researchers, and industry professionals from all over the world to share their ideas, research results, and to discuss the development and innovation in mechanical and automotive technology. It also provides an opportunity for the participants to find global partners for future collaboration.

Industrial revolution 4.0, the internet of things, environmental sustainability, and concern for the disabled person have an impact on every aspect of human civilization including in the field of mechanical and automotive engineering. The need for human resources who are capable of adapting and innovating with various technological advancements to contribute to improving the quality of the environment and people’s lives is increasing. Therefore, the theme of 3rd ICoVEMAT 2020 is “Technology Innovation-Based Mechanical and Automotive Engineering Education for Promoting Sustainable Freedom of Learning”

List of Steering Committee, Scientific Committee, Proceedings Chairs, Organizing Committee, Invited Speakers are available in this pdf.
Redesigning mini compact crucible furnace to improve its performance
Authors: Soemowidagdo AL , Surahmanto F , Rezani R , Pramana SB , Lutfian F
Published: December 2020

Redesigning mini compact crucible furnace to improve heat insulation durability and to obtain the best exhaust pipe position is needed to achieve compatibility for aluminium casting practice. Performance test of the redesigned mini compact crucible furnace was conducted by variation of crucible, support and economizer. The rate of temperature increase, the aluminium melting rate, and gas consumption for melting aluminium specify the furnace performance. The temperature change was determined by digital infrared thermometer. Heat insulator on the inner side wall of mini compact crucible furnace were redesigned by using stainless steel plate cylinder combining with ceramic blanket D.96. Total weight of the furnace decreases by 28%. This insulator combination was able to accelerate the temperature increase, maintain the heating chamber temperature, and reduce the gas consumption. The furnace was able to melt 3 kg of aluminium in 35 minutes by consuming around 1.2 kg of liquefied petroleum gas. The economiser functioned well, was able to accelerate the temperature increase, and maintain the heating chamber temperature.
Isn’t it effective if the transformation of product design tests into 3-dimention modelling?
Authors: Setiadi B R , Puspito J , Sudiyatno  , Kurniawan D , Kartowagiran B
Published: December 2020

This study aims to prove whether changing and transforming into 3D modelling is more effective and efficient than presenting product design job questions in the form of 2D multi-view projection. This research study uses a mix-method with a sequential explanatory design—data collection using questionnaires and observations from video recordings of work. The research object was 28 students taking CAD courses in the Mechanical Engineering Education Department. The Covid-19 pandemic resulted in data collection being carried out online. The results showed that students’ speed on drawing problems with 2D and 3D modelling according to three levels (easy, medium, and difficult) had differences. The 3D modelling view makes it easy for respondents to do it in a short time and with the right results. If explored more in-depth, the thinking skills that dominate respondents according to their perceptions emphasize creative thinking processes and the ability to solve problems.
Experimental study on integrated biomass pyrolysis and gasification process from teak wood waste: preliminary
Authors: Mujiyono  , Nurhadiyanto D , Pratiwi H , Pratama GD , Priyono P , Kassyaf KM , Fauzi FH
Published: December 2020

This study aims to investigate the influence of teak wood waste column height on integrated biomass pyrolysis and gasification process. A design of new conversion process is developed in this study. Teak wood waste was compacted into a gasifier then a hollow like tube gap is inserted in the center of gasifier surrounded by char. Oxygen is passed in the inlet and was flown through the gap. When a flame was initiated, the gap was burned and temperature inside the gap was increased caused the pyrolysis of compressed teak wood happen. There were three different char column height investigated in this study, which are 50, 58 and 67 cm. Compactness of feedstock is set at 0.26 kg/m3. Water boiling test was conducted in order to find the fastest boiling time among the height variation. It is found that the higher the column, the faster the boiling time. Higher char column caused more gas produced due its higher feedstock mass. Furthermore, the gap between each teak wood chip in higher column has increased its ability to release the producer gas.
An Analysis on copper corrosion SUS304 corrugated metal gasket electroplating
Authors: Nurhadiyanto D , Amrullah A M , Mujiyono  , Kurniawati J
Published: December 2020

The objective of this study was to examine the corrosion characteristics on the copper coating on SUS 304 corrugated metal gasket electroplating. The corrosion process on the gaskets coating surface generates an oxide coating which affects the gasket quality both in the decorative aspect and the performance of the SUS 304 corrugated metal gaskets. The experiment method was used in this study. The objects involved consisted of five variants of copper coating thickness of 10, 15, 20, 25, and 30 µm. Each variant consisted of three samples. Analysis on the corrosion was done through the experiment and reference review. The findings show that the 10 µm thickness variant has a near perfect or flawless coating result. The oxide coating formed from the corrosion is not significant. On gaskets with 15 and 20 µm coating thickness variants, copper (I) oxide or Cu2O is formed with a reddish hue characteristic. Meanwhile, on gaskets with 25 and 30 µm coating thickness, two types of oxide coating, namely Cu2O and CuO are formed with a blackish grey hue. The corrosion level is a result of inadequate electroplating process.
The demonstration method using kinesthetic learning style on oxy-acetylene welding practice
Authors: Djatmiko R D , Pradana F N , Prasetya T A , Putra A G S
Published: December 2020

This study aims to determine the differences between students’ learning outcomes using kinesthetic learning demonstration learning methods on the oxy-acetylene welding practice subject for welding technique class grade X students at Sayegan 1 Vocational High School. The research method used was an experimental method with quasi-experimental design research as the research type. The results showed differences between the learning outcomes of welding technique class grade X students between before they were given the treatment and after, using the kinesthetic learning style demonstration method. It could be seen in the results of the assessment: the average post-test scores in the two classes are the highest on the aspect of the assessment criteria number 2 for the experimental and control groups with a value of 0.4. The lowest is in criterion number 8, with a value of 0.25 for the experimental group. For the control group, the lowest is on criterion number 4, with a value of 0.11. This was proved by the increase of the average score on assessment criteria before and after the treatment. Thus, the demonstration method’s effect using kinesthetic learning style on oxy-acetylene welding practices of welding technique class grade X students at Sayegan 1 Vocational High School.
The relevance of machining practices competencies through industrial needs
Authors: Paryanto P , Munadi S , Wagiran  , Purnomo E , Ardiyanto A , Rahmawati E D
Published: December 2020

This study aims to reveal the relevance of practical competencies in mechanical engineering vocational schools to the industry’s competencies in the Yogyakarta Special Region. This research is a quantitative descriptive study using survey research methods with five research subjects representing the manufacturing industry. The results of this study are, in general, the competence of learning machining practices at Mechanical Engineering Vocational Schools is very relevant to the manufacturing industry’s needs. Details of competency relevance data for each practical subject are as follows: (1) competency in lathe machining 42.10% relevant and 57.90% highly relevant; (2) competence of 40.90% milling machining is relevant and 59.10% highly relevant; (3) competence in grinding 33.33% relevant and 66.67% very relevant; (4) numerical control/computer numerical control and computer aided manufacturing competences 2.90% relevant and 97.10% highly relevant.
Online learning of mechanical engineering subject in the Covid-19 era: strategy, platform and media
Authors: Wagiran W , Rahdiyanta D , Wibowo A E , Sati O L , Badu M R
Published: December 2020

The COVID-19 pandemic has resulted in the application of theoretical and practical sessions in Vocational High School being carried out online. The teacher has carried out learning by utilizing information technology in the midst of existing limitations and constraints. This study aims to determine the implementation of vocational education learning in the pandemic era. There were 3 aspects that were the main focus, namely learning strategies, platforms, and instructional media used during the pandemic, both in theoretical sessions and practical sessions. The research method used was quantitative, with a descriptive approach. The research object was 44 Educators of Mechanical Engineering in Vocational High School. The results obtained were: first, the learning strategy that was widely applied in theory learning was 68% independent assignment and in practical sessions was watching video tutorials 27%. Second, Google Classroom was the most widely used as the LMS platform, both in theory sessions at 64% and practical sessions at 27%. Third, material in document form was the instructional media most widely used by educators in implementing 77% theory learning and 57% practical sessions. This research is expected to provide an overview and recommendations for vocational high school educators, especially in the field of Mechanical Engineering in carrying out learning in the pandemic era.
Improve learning outcomes on physics lesson in vocational high school 1 Magelang
Authors: Nurhadiyanto D , Sasongko B T , Ristianto B N , Ibrahim M R
Published: December 2020

This research aims to improve learning outcomes for students. This research was implemented in 2 cycles; at each cycle, there planning, implementation, observation, and reflection. The result of this research is showed that the inquiry method could improve learning outcomes for the student at Vocational High School 1 Magelang on physics lesson. That improved are showed from the amount of score student was obtained; at the first cycle is 2320; meanwhile, at the second cycle are improve and become 2510. During the 1st cycle, the average score was obtained by students is 72,5. During the 2nd cycle, the average obtained was 78,75. In a case of percentage, students who can reach minimum standard criteria are improved too, at the 1st cycle in the amount of 40,6% and improved become 68,75% in the 2nd cycle. This is showed that the implementation inquiry method is proved that can improve learning outcomes for students.
Analysis of the fracture area of tensile test for natural woven fiber composites (hibiscus tiliaceus-polyester)
Authors: Artha Wirawan Willy , Choiron Moch. Agus , Siswanto Eko , Dwi Widodo Teguh
Published: December 2020

The natural fiber is currently widely applied in aerospace applications and the transportation sector. The problem that often arises is the area of failure can be hardly predicted. This condition making it difficult to use fiber in a more complex application. The purpose of this study is to investigate the fracture area of woven natural fiber composites. Hibiscus tiliaceus bast fibers, as reinforcement, were prepared with alkali treatment using NaOH solution and then were added by the coupling agent. The composite was formed using a woven fiber arrangement with 60:40 fiber-matrices mass ratio using a vacuum pressure resin infusion method. The tensile test on the specimens was done on the ASTM D638-03 standard and fracture analysis was performed based on tensile tests. The results of the study show that the narrowing of the fracture area in composites was better and more predictable.
Alternative design of android-based assessment for dynamic-statics basic on mechanical engineering education
Authors: Didik N. , Widiyanti  , Achmad S. Z. , Ba’id F. N. , Ayu M. V. , Siti Z.
Published: December 2020

The low understanding of mechanical engineering education students on dynamic and statics basic impact on their difficulties to learn the course of statics and dynamics and machine design. For this reason, this study aims to obtain a form of dynamic-statics basic assessment design based on android that is easily accessible anywhere and anytime by students. This research was conducted with an R&D design from the Borg & Gall model consisting of research and information collecting, planning, and developing a preliminary form of product. The result of the development was the basic content of the material which consists of two parts: units and basic mathematics. Second result was product design validation indicators to assess the appropriateness of the content and products created. Finally, the main menus display which leading to learning, quizzes, and exit of assessment system. This assessment design will help students to understand the basic statics and dynamics in stages that could be accessed and studied by students through mobile technologies.
Analysis of heat load in coffee bean drying oven room
Authors: Leksono Edy Duwi , Widiyanti
Published: December 2020

Technology has an essential role in the production process which has a function to increase the quality and quantity of production results. Post-harvest coffee bean drying oven technology is needed to speed up the production process, which has been done manually— design and analysis of coffee bean oven machines to produce the effective performance of the oven machines. The method in this study uses the finite element method using ANSYS (Workbench) V 18.1 to analyze the strength of the material and the heat temperature generated from the combustion system. The results of the analysis obtained an average temperature value of 60ºC, with the highest temperature of 200ºC found in the engine furnace because of the initial heat source.
Correlation between total harmonic distortion of load and error percentage of kwh meter on inverter
Authors: Arif Rahardjo Imam , Muslim Suyitno , Subekti Massus
Published: December 2020

This study aims to describe the correlation between total harmonic distortion (current) of load and error percentage of kWh meter to overcome the electric circuit that supplied from inverter through digital kWh meter. The method used in this research was an experimental method with a design set that consists of an inverter connected to incandescent lamp as linear load through power qualty analyzer and digital kWh meter. Next, researcher observed and recorded the total harmonic distortion (current) and energy on the power quality analyzer that connected to the loads circuit for 1 hour. Then compared the energy measurement results with a digital kWh meter, calculated, and analyzed it as an error to be concluded the correlation between total harmonic distortion (current) of load and error percentage of digital kWh meter on the inverter. The load that presented by incandescent lamp affect to measurement of kWh meter. The energy that be consumed of load of 100 watt during 60 minutes is 102.99 Wh. Based on the measurement data, the average error percentage of kWh meter is 2.52% for linear load that caused by 2.85% of total harmonic distortion (current). The higher the total harmonic distortion (current), the higher the error percentage of kWh meter on the inverter that occurs is. And the equation of the correlation between total harmonic distortion (current) of load and percentage of error in kWh meter in inverter gives the R2 of 0,9236 that means the independent factors are not significant.
Design of low jerk automatics transmission for vehicle using fuzzy control to improve gear shifting quality and low fuel consumption
Authors: Marji  , Harly Muchammad
Published: December 2020

Vehicle driveline is the system used transfer engine traction to the wheels. An automatics transmission is the essential and has high role of the driveline. This research was designing a automatic transmission plant and gear shifting logic base on jerk sensing. Which exploit fuzzy mamdani controller. Input variable were throttle-Up and Down position and rate, desired vehicle speed and speed error and even Jerk sensor, while the output of the control was a eight gear shifting actuator. Shifting algorithm was implemented by state machine, which controlled by fuzzy.

Based on discussion of simulation result, the proposed automatic transmission control system produce lower vehicle jerk response, smoother drive comfort and fuel consumption.
Project-based learning to improve learning outcomes and 21st century skills of vocational high school students competency of light vehicle engineering skills
Authors: Apriadi P.F. , Sudjimat D.A. , Yoto
Published: December 2020

In Indonesia, hard skills are more developed by 90% and 21st century skills are only 10% while the world of work demands students has 21st century skills. Project-based learning is a learning model that makes the project to intregate and gather knowledge based on an experience that learners have in real life. This study used experiments because researchers wanted to find out the differences between the group of students who were taught using project-based learning and the method of lecturing students on the competency of light vehicle engineering skills. This study uses pseudo-experimental design using a 3 x 2 factorial design. The group of students used in the study is class X learners of SMKN Bali Mandara Light Vehicle Engineering competency. It consists one control class and one experiment class. Pretests for knowing the initial ability of high, medium, low and post tests are used to find out the learning outcomes of students. hypothetical test of study results among the group of students taught using a project-based learning model using a lecture model with a coefficient value of F calculated at 4,174 and a signification value of 0.002, so that H0 in reject and H1 are accepted. Testing of the 21st century skills hypothesis between the group of students taught using the project-based learning model and using the lecture model showed an F coefficient value of 4,050 and a significant value of 0.003, resulting in H0 being rejected
The influence of centrifugal particulate matter reducer on gas opacity and fuel consumption of inspection train
Authors: Rozaq Fadli , Artha Wirawan Willy , Hari Boedi W. , Dadang Sanjaya A. , Nurtanto Muhammad
Published: December 2020

This study aims at determining the level of exhaust gas opacity and fuel consumption using a centrifugal particulate matter reducer in a diesel-engine inspection train. The opacity level was tested using a smoke tester and fuel consumption measurement per 30 seconds. The test was carried out by varying the types of diesel fuel including Bio-solar, Dexlite, and Pertamina Dex. Based on the test results, there is a decrease in exhaust gas opacity for the use of Bio solar and Dexlite fuels by 5.75% and 6.3%, while the type of Pertamina Dex gained an increase of opacity by 0.6%, respectively. Besides, it was an escalation of fuel consumption in Bio-solar and Pertamina Dex by 7.7% and 2.7%, respectively, while Dexlite did not change the amount of fuel consumption.
The utilization of moving train as an alternative energy sources in railways with savonius wind turbine
Authors: Utomo Ilham Satrio , Atmaja Dadang Sanjaya , Wicaksana Yoga
Published: December 2020

The purpose of this research is to obtain the dimensions of the savonius wind turbine and to test the calculation results and design of the savonius wind turbine based on the wind speed generated due to the movement of the train in the tunnel. The method used is to calculate the dimensions of the turbine diameter. The results of the calculations show that the savonius wind turbine diameter is 60 cm with a height of 60 cm. The maximum voltage generated is 12.26 V with a current of 0.52 A at a wind speed of 5.7 m/s.
The utilization of waste cooking oil (wco) in simple stove as an alternative fuel for household scale
Authors: Susilawati  , Zamzami Rifaul , Buchori Azhis Sholeh
Published: December 2020

The use of LPG (Liquefied Petroleum Gas) fuel as a substitute for kerosene fuel on the stove has advantages in its excellent combustion process, but there are several weaknesses in its use, namely the risk of gas leakage in the LPG cylinder, and of course the high price of LPG cause increasing the community burden. The purpose of this study was to produce a waste cooking oil simple stove on a household scale. This research used an experimental method which was conducted for 6 (six) months, began from February 2020 to July 2020. The stages of the research were data collection, making waste cooking oil stove design, preparing tools and materials, making waste cooking oil stoves and testing it. The results showed that the flame produced on the waste cooking oil stove was stable, but the resulting fire was still red due to the incomplete combustion process caused by the lack of air/oxygen pumped into the stove. The advantage of this waste cooking oil stove is the simple installation, portable to use, inexpensive manufacturing cost and more safety than using LPG stove.
The Development of Engine Management System’s Learning Media Video in Lightweight Vehicle Engineering Expertise Nasional Berbah Vocational High School
Authors: Fatin N N , Arifin Z
Published: December 2020

This research aimed at (1) developing the engine management system’s learning media video, (2) knowing the feasibility of developing the engine management system’s learning media video with assessment from media and material, also (3) knowing the responses of the lightweight vehicle engineering students of National Berbah Vocational High School toward the engine management system’s learning media video. The research of the engine management system’s learning media video is a research and development (R&D) study that employed 4D development model (Define, Design, Develop and Disseminate). Data collection technique carried out front analyses and questionnaires then analysis of feasibility is carried out by describing it into five categories such as the Likert scale. The results of this development study are the engine management system’s learning media video contained the three materials which were characteristics, functions, and the working of sensors, actuators, and electronic control unit, the media feasibility of this learning media is determined by assessment of material expert (4.3), media feasibility based on media expert (4.1), then student responses as the user get a grade (3.5), so the engine management system’s learning media video was feasible to be used in the learning process.
Development of Tutorial Video Learning Media on Engine Management System Diagnosis
Authors: Agama A A , Solikin M
Published: December 2020

Students readiness before participate in the practice activity need to be well prepared through a tutorial video for practicing. Therefore, this study aimed to (1) develop the Learning Media Video Tutorials for Engine Management System (EMS) practices in the Automotive engineering class, and (2) Identify the feasibility of the learning media developed. A research and development approach was implemented. There were two experts analized the product. The results showed that (1) the product is a tutorial video on a vehicle’s EMS diagnosis using a scanner, (2) the utorial video is an.MP4 form with a file size of 2552 MB, which can be played through smartphones or computers, (3) the contents of the tutorial video is consisting introduction, DTC Function, Current Data Function, and Oscillsocope Function, (4) experts validity revealed that the tutorial video for diagnosing EMS on a vehicle is good and feasible to be implemented in the classroom activities. A further study to identify the effect of the tutorial video on the student’s achievement is suggested.
The Development of Learning Media’s “Tutorial Video for Setting the Front Wheel Alignment With a 3D Spooring Tools” at SMK N 1 Magelang
Authors: Prihantono M R , Usman T , Wakid M
Published: December 2020

This study aims to: (1) Produce a learning media’s tutorial video for setting the Front Wheel Alignment with a 3D Spooring tool; (2) find out the feasibility of developing a tutorial video for setting the Front Wheel Alignment with a 3D Spooring tool for learning media on Light Vehicle Engineering Department in Vocational High School 1 Magelang. The type of this research is Research and Development (R&D) using the 4D model (define, design, develop, disseminate) because more clearly the steps in each stage of this model. Data collected by observation, interviews, and questionnaires. The video feasibility assessment in this study was conducted by one material expert, one media expert, and 30 students of XII OA class in Vocational High School 1 Magelang and then converted to qualitative data with five eligibility categories. The results of this study are tutorial video for setting the front wheel alignment with a 3D spooring tool which gets a score of 3.94 (feasible) from material experts, from media experts get a score of 4.11 (feasible), and student opinions get a score of 4.41 or 88.11% (very feasible) so that learning media’s tutorial video for setting the front wheel alignment with a 3D spooring tool is very suitable for use in learning.
Developing Learning Media of Electronic Fuel Injections (EFI) System Android-Based in Piri 1 Yogyakarta Vocational High School
Authors: Ikhsan M R , Solikin M , Rohman J N
Published: December 2020

This research aims to: (1) producing android-based Electronic Fuel Injections (EFI) learning media; (2) knowing the feasibility of android-based EFI learning media; and (3) knowing students’ responses to the learning media of the Android-based Electronic Fuel Injections (EFI) system. The rsearch was conducted using the Borg and Gall model modified by Sugiyono. The technique of data collection is done by questionnaire, while the data analysis technique uses descriptive quantitative methods. The results of the research were obtained: (1) products in the form of Android-based Electronic Fuel Injections (EFI) system learning media; (2) learning media in terms of material included in the very feasible category and in terms of media included in the very feasible category; and (3) students’ responses when testing the product, the aspects of use are included in the category very easily and the aspects of usefulness are included in the category of very useful. The response of students when testing the use, the aspects of use included in the category is very easy and the usefulness aspects including the category is very useful.
Wheel-hub and Upright Development on GE 19 Racing Cars for International Student Car Competition
Authors: Wakid M , Hidayat N T , Setiawan W D
Published: December 2020

This study aims to produce proper designs of the wheel hub and upright components of a GE 19 racing car. The design results were analyzed using analysis software to ensure the strength of the steering system components is safe in every driving condition. The upright and wheel hub which are designed are the developments of the EVO 14 racing car. The development This development was carried out because there was a change in the drive system from which the car initially used front drive to rear drive. In addition, the development also aims to minimize the occurrence of cracks in the upright and wheel hub components. The method used in this development is the Engineering Design Process model. The object of this development is the wheel hub and upright design which will then be applied to the GE 19 car to participate in the 2019 International Student Car Competition. The data analysis technique used is a power simulation using the Finite Element Analysis (FEA) feature on Solid works. FEA simulation data is in the form of stress contour images and safety factor values for the wheel hub and upright components of the steering system at each driving condition. The results of this development indicate that the design of the upright components and wheel hub of the GE 19 car has good strength and safety factors in every driving condition.
Online Learning Model in The Pandemic Time COVID 19 at SMK Negeri 1 Saptosari Yogyakarta
Authors: Sofyan H , Isnantyo F D , Fu’adi  , Pratama A
Published: December 2020

This research is a qualitative descriptive study, the purpose of this research is to: (1) Find out what online learning models are used by SMKN 1 Saptosari teachers during the Covid 19 pandemic; (2) Describe the technical steps for developing an online learning model for subjects at SMKN 1 Saptosari; (3) obstacles experienced by teachers in implementing online learning; (4) Efforts to overcome obstacles. This research was conducted at SMK N 1 Saptosari with research subjects Teachers of productive subjects who represent the existing expertise competencies at SMK N 1 Saptosari as many as 40 people, data collection was carried out by observation techniques in schools when the teacher was doing online learning, interviews with teachers productive, and instruments in the form of a questionnaire used to reveal data on online learning models, the obstacles faced and efforts to overcome them. The results showed: (1) The online learning model used by SMKN 1 Saptosari teachers during the Cocid 19 pandemic used the following platforms: google classroom, google meet, Zoom, WA group, youtube channel, and Microsoft 365; (2) The technical steps for developing an online learning model for subjects at SMKN 1 Saptosari include: (a) Initial analysis to identify the online learning model and platform used; (b) Determination of material; (c) Implementation of lecture, discussion, and mentoring methods in preparing material, structuring the material so that it is easily accessible to students, real-time interaction, role playing; (d) Preparation of RPP; (3) Obstacles faced: (a) Teachers do not master the internet well, (b) Internet quota is limited, (c) The signal is not supportive, (d) Not all students have laboratory devices, (e) Students and their parents are lacking understand the procedures for learning through online well; (4) Efforts are made: (a) Organizing online learning workshops for teachers, (b) Creating class group WA, (c) Simplifying the material so that it is easily accessible and understood by students, (c) Providing internet quota assistance for students, (d) Conduct home visits for students who encounter problems, (e) Provide a grace period in collecting assignments.
Designing Shell Eco Marathon Car Bodies with Solid Work
Authors: Gunadi  , Fergianto F
Published: December 2020

The Shell Eco Marathon is a world-class car competition for students. Through this competition, students compete to create innovation and creativity in the development of vehicle technology. The final result of this competition is the birth of vehicles that are economical, environmentally friendly, including a lightweight and aerodynamic body. This study aims to produce an urban concept car body design for racing purposes, with several provisions that comply with the Shell Eco Marathon competition regulations, have a low drag coefficient and turbulence value. This research includes research and development (R&D), using the ADDIE development model (Analysis, Design, Development, Implementation, and Evaluation). The test object is the 3D urban concept body shape design. The development of the urban concept body design uses the Solid work 2018 software with a flow simulation feature to analyze 3D urban concept body shape designs. The results of this research and development are (1) the design of the car body shape has met the competition regulations, (2) the drag coefficient value can be achieved at 0.1965, and (3) the value of turbulence intensity can be achieved at 0.133%. The results showed that the development of the urban concept body shape design was as planned.
Multi-Channel Method of Non-isolated DC Voltmeter for EFI Instrument Measure
Authors: Adiyasa I W , Solikin M , Khalid H , Umar A , Riyan I N
Published: December 2020

The use of instruments for vehicle repair is very important to use. However, the instrument is very expensive and many features are not used. So that in this study designed a simple measuring instrument that is able to measure the size of the sensor. The tool uses a 32bit based microcontroller integrated with bluetooth. There are 4 voltage gauge channels. The reading data is communicated to the graphic user interface (GUI) on the laptop device. The measuring instrument can record the measured sensor on a vehicle for 1 minute for analysis.