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Sorghum is a plant with broad adaptability, is resistant to drought, and is very suitable in marginal areas. Sorghum plants contain 7% to 17% seed composition and 83% to 93% leaf stems. At harvest, the moisture content of seeds is 20% to 30%, and the stem is around 76% to 88%. Several stages are carried out after the sorghum harvesting process, and one of them is threshing the sorghum seeds. The threshing of sorghum seeds requires a hold-on threshing machine so seeds can be threshed immediately after harvest, and the stems from sorghum plants can be chopped directly for cattle feed. This study aims to design and test the performance of a hold-on type sorghum threshing machine that can be used to thresh sorghum seeds immediately after harvesting at a grain moisture content of around 20% to 30%. The methods used include problem considerations, the preparation of structural designs, functional designs, manufacturing drawing designs, and manufacturing functional and performance testing. The results of testing the performance of the threshing machine revealed that the working capacity of the machine was affected by rod clamp rotation, the threshing cylinder, and the moisture content of sorghum seeds. The cleanliness level of sorghum seeds is above 90%, while the level of seed damage ranges from 0% to 1%.

The student's criterion for being diagnosed with MLD (Mathematics Learning Disabilities) can be classified as low arithmetic skills and poor working memory. The goal of this research is to understand students' process of thinking through the Polya stages when tackling arithmetic problems, as it has been expounded by Dr. Polya For students who have mathematics learning difficulties, the information is gathered by administering math problems to both females and males that ask the correct questions and have to be answered in their heads. the data gathered from the study concluded that students exhibit degrees of mental disorder that are caused by 3 distinct stages in which they must be addressed: problem-solving underachievement, when they are overreaching, and cognitive imbalance when they are overcommitted. to arrive at equilibrium, the more significant expansions must be coupled with an extensive assimilation and assimilation process As students with moderate to severe learning disability were completing multi-digit addition and multiplication, they underwent assimilation. Because of this, the cognitive fluidity present at this moment, the students have already found themselves in their present-looking-backward state of mind.

This study has developed a digital mathematics handbook that helps students to strengthen their mathematical skills at the elementary level of education. A survey of mathematics teachers collected data. In developing an integration manual on technology based on a survey of the state of technological integration in schools, it employed a research and development (R&D) approach. A number of 24 teachers participated in the material creation. The multimedia materials produced during the trial were developed and used. Participants consisted of primary learning children. Results have shown that the trainers' preferred theory is undergraduate, and most of them have a poor capacity to integrate creativity into a research analysis. In the presentation of the under-graduates in mathematics the material produced was extremely good.

Rubber Conical Bonded (RCB) is a component that connects the wheel with the train bogie, which functions to dampen vibration and noise. This RCB is made of rubber. In this research, RCB vulcanizate will be made with a mixture of natural rubber (RSS 1) and rubber waste. Rubber waste is the residue from the production process of technical rubber goods or rubber technical goods that are no longer used. This rubber waste goes through a devulcanization process to be reused as a raw material. In this study, rubber waste derived from the residue of the production process was varied with the phr ratio as follows: RSS 1 / Rubber waste / Devulcanized rubber waste (RCB0: 100/0/0; RCB10: 90/10/0; RCB30: 70/30/0; RCB50: 50/50/0; RCB10X: 90/0/10; RCB30X: 70/0/30). The vulcanizate obtained was then subjected to physical characterization (before and after aging 24 hrs; 70oC) and compared with the technical specifications of the RCB. Physical characterization includes Tensile Strength (min 14 N/mm2), Tear Strength (min 26 N/mm2), Hardness Shore A (50±5), Elongation at Break (min 400%), and Compression Set (max 30%). The results show that all variations meet the specifications for tensile strength, tear strength, and hardness.

Railway bridges are crucial for transferring passengers and commodities in the transportation network. Railway bridges require continuous monitoring to observe their performance. A structural health monitoring system is one method for assessing the viability of a railway bridge structure. The functioning of railroad bridge structures has been extensively observed using wireless technology. This research aims to implement smart wireless sensors for monitoring the structural health of the railway bridge online in real-time during operation. Many sensors were installed on the railway bridge, including strain gauges, accelerometers, linear variable displacement transducers, and proximity sensors. Geometric modeling and numerical simulation were performed to find critical frame locations on the railway bridge where the instrumentation sensors would be placed. In this study, MONITA® is employed for data acquisition modules. The MONITA® system consists of a combination of hardware and software that functions to retrieve, send, store, and process data. This paper describes the result of establishing this method to comprehend the performance of the steel railway bridge structure in real-time via the human-machine interface display dashboard. As a result, the monitoring system can appropriately assess a structural railway bridge in real time. This study may be helpful to practicing engineers and researchers in future studies of steel railway bridge evaluation. This could be a valuable reference for future studies in implementing such systems as the railway bridge early warning system technique in detecting bridge damage. [ABSTRACT FROM AUTHOR]

Hebel brick is used in making the walls of the house. One of the materials used in making hebel bricks is sand. The water content of the sand will affect the quality of the hebel bricks. The less water content in the sand, the better the quality of hebel bricks. In order to get sand with a little water content, it is necessary to do the drying process. To overcome this problem, a rotary dryer for sand drying using renewable energy, particular biomass energy sources was designed. It can be placed in a sand quarry near a river or near a beach. It is designed to have the ability to dry the wet sand by putting it in a rotary dryer, making this drying system usable both in sunny and rainy conditions. The drying process can take place continuously using heat from biomass energy. The heat is produced from the combustion process in the biomass furnace and then distributed to the rotary dryer. The advantage of this rotary dryer system could be done continuously with a little human power. Moreover, from these calculations can be analyzed the performance of this rotary dryer machine, to determine the suitability between design calculations and test results.

The purpose of this study is to perform the techno-economic analysis of photovoltaic system utilization for lighting and cooling of Ferry Ro/Ro 500 GT. The world is facing a dilemma of increasing dependence on fossil energy with decreasing supply. This situation must be anticipated by all sectors by energy efficiency (EE) and utilizing renewable energy (RE). Especially for RE in the transportation sector, ships as consumers of oil energy can also take advantage of solar energy sources, for example for lighting and cooling. For that purpose, five steps must be taken. First, determine the design specifications. Second, determine the specifications of components of the PV system. Third, calculate the power required for lighting equipment. Fourth, calculate the power required for the cooling system. Fifth, make an investment comparison for propulsion systems between diesel engines and photovoltaic systems. The results show that the energy required for lighting and cooling system as well as for propulsion systems can be placed in the deck area of 148.8 m2 for all system components, such as; PV modules, charge controllers, batteries, and inverter. This study can provide an overview of the use of PV system in designing the environmentally new or renovation ships.

The need for beef in Indonesia continues to increase. In 2020, it will require imports of 300 thousand t of meat or the equivalent of 1.7 × 106 cattle a year. To overcome the problem, the biogas-energized livestock feed making machine (copper) was designed. The advantage of this copper is the process of making the livestock feed can efficient and effective. Results of the calculations, known that with increasing miller rotation output, the resulting capacity shows an increase. Also, it can use drive motors that are available on the market with a power capacity of 50 W. Hence; this machine is very efficient in the use of electricity, high economic value, convenient and easy move to other places. Electricity for the engine is designed with renewable energy, namely biogas from co-digestion substrates namely animal feed waste, kitchen waste, cow dung and excreta disposal from septic tanks. This co-generation is expected to improve the life of the breeders

Energy demand increases in line with rapid technological advances. Research on the harvesting of renewable energy continues to be done to make efforts to convert heat energy, which is very abundant in our daily environment. Thermoelectric technology is an alternative source in answering energy needs and can produce energy on a large and small scale. Thermoelectric technology works by converting heat energy into electricity directly, or from electricity to cold. This research presents an experimental study conducted to find out the thermoelectric characteristics of the TEC in the reversal function, with heating and cooling tests on each side of the TEC type thermoelectric element, carried out to obtain the voltage value as the electrical potential generated from this element. The result is thermoelectric potential to generate DC electricity but is very limited in the function of maintaining a heat source on the hot side element. This research then proposes thermal metamaterial that functions as a collector of thermal energy in the method of converting thermal energy into DC electrical energy for the application of low power consumption communication systems.

Indonesian villages are facing dangerous condition. Every year, young people are deserting the villages. To overcome this problem, Tangsi Jaya hamlet, West Java, has been provided with 18 kW micro-hydro to supply electricity both to the community and to Small Processing Center for ground coffee production. Results of cash flow analysis for ground coffee in Tangsi Jaya hamlet, with total investment of IDR 110 750 000 and discount rate of 18 % for 5 yr. Banyumeneng I hamlet, Yogyakarta with an investment cost IDR 95 000 000 and production cost of IDR 34 195 000 yr–1 and the interest rate of 14 % yr–1, the payback period was estimated to be 3 yr with ROI of 40 %. PEST analysics indicate that the higher electricity tariff and interest rate while the higher the value of technology and number of people involve with the SPC will result in the bigger value of ROI. Renewable energy technology could be used for value added activities in rural areas, create small industries, provide job opportunities to the local people and create conditions for sustainable economic development. However, vigilance is needed because small industries can also cause pollution because they produce waste

The purpose of this study is to conceptualize Indonesia’s ICT-based energy security tracking system with detailed indicators of renewable energy (RE) and energy efficiency (EE) from the smart city extension. The opportunities for improvement to the energy security system is still wide open with the support of advances in information and communication technology (ICT) to integrate the internet and smart grid. The method refers to five main dimensions: availability, efficiency, affordability, sustainability, and governance. Then, how to link the concept of energy security with detailing indicator of RE and EE to the smart city. Empirically, energy security is a function of availability, efficiency, affordability, sustainability, and governance. The most important dimension is the Government (Go) to realize the interconnectivity and the information. If the Go has been realized, the other four dimensions will be easily obtained. With the development of ICT, the energy security status will certainly be more easily accessed anytime and anywhere by the stakeholders. The concept of a smart city usually integrated with the ICT infrastructure, especially for monitoring, management and decision-making tool. This research provides an overview of how the concept of energy security system is closely related to the implementation of the smart grid.

The aim of this research is to determine the performance of PV panels, wind turbines, battery storage and power imported from the grid to the system which will ensure a reliable energy supply, as well as the technical feasibility of a smart microgrid system. Indonesia’s renewable energy potential for electricity reaches 443 GW, where solar energy is the largest potential, namely 4.8 KWh m–2 or equivalent to 112 000 GWp, but only 10 MWp has been utilized. The most basic problem in this system, namely, the uncertainty of wind energy and solar energy, one of the most vital factors in the optimal size of a renewable energy-based smart microgrid system is the reliability of the system being built. The method used in this research is to collect data on the availability of wind energy and solar energy as well as load analysis on the smart microgrid system. As a result, the resulting power output was 6.2 MWh during the experiment. The highest average Performance Ratio (PR) of the solar energy power generation system, namely 77 % in February 2020. Optimized with Battery Life (OBL) model produces a power output of 102.4 kWh and has an overall system efficiency of 81.92 %.

Indonesia is an archipelago that has a wealth of marine fish resources, and the country with the second-longest coastline in the world. The improvement witnessed in the economy of Indonesia in recent years, is as a result of the growth experienced in various sectors, among which is the fisheries and marine. To overcome this problem, a portable conveyor system of moving equipment for fishermen’s catches was designed. It can be placed at the dock or port where the fishermen are anchored and unloading the fishermen’s catches from the sea. It designed to have the ability to move up and down in the moving frame, making this conveyor system can be used both in high tides and low tides of seawater level conditions. The advantage of this portable conveyor system is could be done continuously with a little human power. Other than that, from the results of the calculations, known that with increasing motor rotation, the required traveling time will only become shorter. The resulting conveyor capacity shows an increase. Also, it can use drive motors that are available on the market with a power capacity of 0.37 kW. Therefore, the process of this portable conveyor system can be more efficient.

The purpose of this study is to analyze the potential for energy savings because the laundry industry consumes a lot of energy and water. If the laundry industries are not controlled, it will cause serious environmental and energy problems. The audit activity was divided into three stages. Pre-audit stage, the auditors were divided into groups with clear details of tasks and responsibilities, starting with conducting energy audits on the floor, analyzing statistical data, and process flow. Site audit stage; conduct an audit on the floor from the beginning to the end of the process, then collecting and confirming the statistical data for energy and production. Post-audit stage, complete the audit report that will be submitted or presented to the laundry management, which consists of; audit findings with loss or savings analysis, accompanied by recommendations for further improvement. The results show that there are many savings opportunities, especially by overcoming the energy wasted in the production process. Improvements can be made by overcoming energy waste and controlling energy consumption and production more efficiently, implementing renewable energy technology such as solar dryer and hybrid photovoltaic and thermal (PVT) collector, and then considering industrial revolution 4.0 with IoT and ICT.

Wind energy is one of the primary energy sources that can be used to produce electricity. Indonesia has the potential to harness wind energy to produce electricity due to located on the equator, especially in coastal areas. An alternative to the availability of electricity in remote coastal areas is to use small-scale wind power plants. One component that plays an important role in wind power generation systems is the generator. A generator is a machine that converts mechanical energy into electrical energy. In small scale wind power plants, permanent magnet synchronous generators (PMSG) are commonly used as energy conversion machines. In this paper, a PMSG has been designed for small-scale and low-speed wind power generation as an energy conversion machine. PMSG which has been designed has the following specifications: 500 W, three phases, 18 slots, 12 poles, with a rotation speed of 500 rpm. The simulation test results obtained the following data, the output phase-phase maximum voltage of the generator is 38.84 V, and phase maximum voltage is 22.5 V.

Sorghum is a versatile plant with various parts that can be utilized. However, information on the physical and mechanical properties of the sorghum plant is crucial for designing agricultural machinery for primary handling processes such as threshing and chopping. This study aimed to determine the technical characteristics of sorghum plants (Bioguma variety) including the physical and mechanical properties of the stems, leaves, panicles and seeds to design a configuration system concept for threshing and chopping machines capable of processing sorghum plants with high moisture content immediately after harvesting. The study used a descriptive method and included samples of sorghum plants randomly taken from fields in Majalengka and Bogor, Indonesia. The physical and mechanical properties were measured using several replications, ranging from 3 to 30 depending on the parameter. The sorghum plants were harvested at at ages 80, 90 and 108 days after transplanting (DAT). It was found that the moisture content of sorghum stem and seeds decreased with the increase of plant ages where stem ranged between 84.18-79.81 %wb and seeds ranged between 51.7-29.4 %wb. The result revealed that planting ages influenced its properties including stem properties and seed properties. Longer DAT increased the stem hardness from 290.64 ± 29.41 to 350.00 ± 0.81 N and seed hardness from 8.2 ± 1.7 to 44.9 ± 5.4 N but decreased the tensile force of seed form panicles from 16.7 + 3.2 to 6.0 ± 0.8 N. The data on stem strength and seed hardness provide important considerations for the development of several equipment for sorghum processing. The findings of this study can serve as a basis for designing effective and efficient threshing and chopping machines for sorghum plants at high moisture content. [ABSTRACT FROM AUTHOR]

In recent years, due to its feasibility and reliability, the organic rankine cycle has become a widespread concern and is the subject of research. In the organic rankine cycle system, the radial turbine component is a highly influential component of the high low performance resulting. This paper discusses the design of radial turbines for organic rankine cycle systems. The design stage consists of preliminary design and detail design with parametric methods on the working fluid R22 to determine the geometry and initial estimation of the performance of the radial turbine. After that, a numerical study of the fluid flow region in the radial turbine with R22 as the working fluid was performed. The analysis was performed using computational fluid dynamics of Autodesk Computational Fluid Dynamics Motion software on two models of real gas, k-epsilon and shear stress transport. From the results of this analysis, there is pressure, velocity and temperature distribution along the radial turbine blades and estimated performance under various operating conditions. Comparison between parametric and computational fluid dynamics analysis results show different performance. The difference is due to the computational fluid dynamics analysis already involving the real gas shear stress transport model.

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The research aimed to reduce the amount of coffee pulp (CP) as a pollutant and turn it into Coffee Cherry Fluor (CCF) as a functional food. CCF is expected to serve a function as a non-heme iron source to treat anemia. Further, reusing CP should be able to boost the circulation of economy. Six CP samples from three Arabica coffee areas (highlands of Mount Batur, Mount Ijen, and Mount Arjuno) in Indonesia were compared to La Boite CCF, a commercial product made in Brazil. Variables observed were iron contents which is determined by Inductively Coupled Plasma Optical Emission Spectrometer, vitamin C contents as enhancers by Iodimetric titration, total phenol contents as inhibitors by Folin-Ciocalteu method, tannin contents by spectrophotometry method, lignin contents by Van Soest method, total plant count by ISO 4833-1, and antioxidant capacity by IC 50 in the DPPH scavenging assay. Sample disparity significance was statistically determined by ANOVA, followed by Tukey test at 95 %. Sample resemblance with La Boite CCF was tested using Principal Coordinates Analysis (PCoA) and then presented in Heat Map. Conclusively, Mengani CCF and Mengani CP Estate samples are similar to La Boite CCF regarding vitamin C and inhibitor contents. It is suggested to reduce the temperature of the artificial drying device in Mengani. Further research should cover heavy metal contents, proximate analysis, and the detail of amino acid contents as research observed variables; expanding this research in vivo to study non-heme Fe's bioavailability should also be conducted. [ABSTRACT FROM AUTHOR]