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The shaft propeller is one of the most important parts of ship propulsion installations. To produce a good quality shaft propeller, the ship propeller designer must consider various parameters to produce the type and size of the propeller that has the value of effectiveness and high propulsion efficiency. Shaft propellers are usually made of steel, but the propeller shaft model is made of Aluminum Alloy base material in this study. So the material must have good mechanical properties. This study aims to see the mechanical properties of the sheller propeller with aluminum alloy base material with the addition of silicon elements and magnesium by going through the heat treatment process. The main base material used is 6063 aluminum alloy, with variations in the addition of Si (1, 2, 4 wt%). The addition of Mg can improve the mechanical properties of the casting. Alloy Al6063 is heated to a temperature of 790°C to reach a complete liquid state. Then the temperature is lowered to 645°C, then the Si element is inserted into the heating furnace and stirred. Then the temperature is lowered to 615°C, then the Mg element is added, then stirred thoroughly by a mechanical stirrer. The rotational speed of the stirrer is 70 rpm and the stirring time is 240 seconds. Then heated to a pouring temperature of 670°C. The mold is heated to a temperature of 265°C. Then poured into the mold and pressed 7 MPa. After that, it was allowed to stand for 600 seconds and removed from the mold. The cast propeller shaft is cooled at room temperature. Then the propeller shaft was heat treated with a solution treatment temperature of 485°C for 3600 seconds and then quenched using a fluid. After that, the casting products were treated with artificial aging. The results of the study are, Porosity will decrease along with the addition of Silicon elements. The lowest porosity level is in addition to 3% wt Silicon which is equal to 1.15%. Tensile test with the addition of 1% wt Silicon ie, 106.882 MPa, in addition of 2% wt Silicon that is, 128.713 MPa, and in addition of 3% wt Silicon ie 132.668 MPa. So the highest tensile stress value is at 3% wt. Hardness values will increase with the addition of Silicon elements. The highest hardness value was found in the variation of 3% wt Silicon ie, 69.9 HB. While in the variation (0, 1, 2% wt) that is, 43.75 HB, 51.24 HB and 56.45 HB. So this study, proves that adding silicon elements can improve the mechanical properties of the shaft propeller. [ABSTRACT FROM AUTHOR]

This paper proposes a novel power generator by adopting the concept of a footstep generator. We have modified this generator to be implemented at toll gates and harness the weight of vehicles passing through the generator, converting the kinetic energy generated by the vehicle's pressure into electrical energy. Our research capitalizes on the substantial traffic volume in Indonesia by introducing a modified and redesigned footstep generator that can be implemented on toll roads, referred to as a highway generator. The number of vehicles passing through toll roads in Jakarta province reached a total of 644,390,960 vehicles. By utilizing this highway generator, there is a potential to generate 26,435 GWh of electricity for a year. Moreover, this significant device also contributes to the reduction of CO2 emissions stemming from fossil fuel usage, amounting to 17 thousand tons of CO2 gas. [ABSTRACT FROM AUTHOR]

Nowadays, an increasing number of parents are providing their children with gadget to be used as entertainment purposes by encouraging their children to watch videos and play games as part of their daily activities. This habitual interaction with screens can significantly impact both the health of the child and the environment due to CO2 emissions. This research aims to investigate the effects of screen time on children under 5 years old and explore the environmental impact stems from emissions generated throughout the screentime, from production to their day-to-day usage specifically at Tsabitha Day Care in Depok, Indonesia. To examine the effect of screen time on children aged 2-5 years, this study proposes the development of a game prototype that will be implemented and evaluated at Tsabitha Day Care. The research will primarily focus on the cognitive abilities of children in the target age group, with a specific emphasis on their performance in both analog and digital memory game tasks. The ultimate goal of this research is to propose a time-limitedmemory game that will effectively curtail excessive smartphone usage among young children and, consequently, lead to areduction in emissions. [ABSTRACT FROM AUTHOR]

Balinese saka calendar has a system of good and bad days called Ala Ayuning Dewasa. This system included a variety of activities. One of them is cayenne pepper farming. The farmers in Bali have used the Ala Ayuning Dewasa as a guide in planting because they are believed to coincide with favorable natural conditions. However, there has been no empirical evidence regarding the suitability of the system. This study aims to begin empirical evidence by showing a correlation between this system and optimal air temperature and humidity in growing cayenne pepper. This study uses the formula y = sin ( π 105 ∘ x + 90 ∘) as a mathematical model of the Ala Ayuning Dewasa, where the maximum cycle value (y = 1) represents a good day and the minimum value (y = -1) indicates a bad day. Correlation was measured against the initial assessment of the accuracy of a day as the beginning of cayenne pepper planting based on temperature and air humidity for three months after (time needed from planting to harvesting). The assessment was carried out using temperature and humidity data from October 1, 2014 to January 1, 2017. The comparison shows that there is no correlation between the two with correlation value of −0.161. However, the results of observations show that there is a similar pattern even with the beginning of a different phase. By revising the beginning of the Ala Ayuning Dewasa calendar by 60 days, the correlation value becomes 0.799. The suggestion from this initial research is to shift the beginning of Ala Ayuning Dewasa planting of cayenne pepper by 60 days to increase the correlation with optimal temperature and humidity conditions for cayenne pepper growth. [ABSTRACT FROM AUTHOR]

The education system today has progressed very rapidly. This is indicated by the many different ways used in the teaching and learning process to deliver material to students in the hope that the teaching delivered is more memorable and the learning activities carried out by students are more meaningful. Recently, in the teaching and learning process, many have used information and telecommunications technology, which is expected to advance the quality of education in line with technological advances. The development of multimedia technology opens up great potential in changing ways of learning, obtaining information, and so on. The effect of this multimedia also opens opportunities for educators to develop learning systems to get optimal results. Likewise, for students with multimedia, it is hoped that they will find it easier to determine in what way and how to absorb the information conveyed quickly and efficiently. The Human Coordination System is one of the biological materials in human physiology with complex concepts that cannot be fully visualized. The abstract idea is then concretized in the form of audio-visual and animation. Auxiliary media cannot be separated from computer technology (hardware) and software technology (software). The Computer Assisted Instruction (CAI) model uses computer tutorials to assist in the tutorial's learning. The activity model is a program designed to act as a tutor or teacher. The method for creating this model is to develop an implementation plan that follows the learning material according to the specified curriculum, then visualize it in a computer program in the form of attractive media to increase student motivation. In this research, an online-based human coordination system learning application will be designed to support the material learning process equipped with interactive question-and-answer questions so that students can find out to what extent they understand the material being taught. [ABSTRACT FROM AUTHOR]

The goal in writing this thesis is to create an online learning system, especially for Citizenship Education subjects, with the development of information systems and also the development of multimedia which helps conventional education systems that occur in class, where students can directly meet face to face to support the learning process so that researchers conduct surveys such as collecting data in the form of questionnaires from several respondents such as students to support the creation of an online learning system for Citizenship Education subjects using the ADDIE method, software used to design e-learning using the PHP and MySQL programming languages, after that the researcher also evaluated the online learning. The result of creating an online learning system for Citizenship Education subjects is to help students in the learning process by e-learning without any time limit, which makes students more effective in the lesson and also makes learning independent so that students/students can evaluate learning. One of the learning models that can be developed is the ADDIE model. This learning model emerged in 1967 and was created by Reiser and Molland. One of ADDIE's functions is to serve as a guideline in building training program tools and infrastructure that are practical, dynamic, and support the training work. This model was chosen because the ADDIE model is often used to describe a systematic approach to instructional development. In addition, the ADDIE model is a general learning model, so it is very appropriate to be developed in classroom learning. When used in education, this process is sequential but interactive, where the evaluation results of each stage can lead to the development of learning in the previous setting. [ABSTRACT FROM AUTHOR]

A website is a page containing information that can be viewed if the computer is connected to the internet. With a website, everyone in the world can get and manage information from various sources available on the internet. The website itself can currently contain various kinds of media, ranging from text, images, sound, and even video. With the existence of a website via the internet, Mandiri Arts Crafts decided to use the website as one marketing medium so these products and products can be wider and known to the wider community. The people around and especially the city of Medan also don't have to bother getting the desired product and don't need to come directly to the product distribution point which is very attractive, beautiful, and worth selling. Study This paper discusses an online-based marketing information system for handicrafts from water hyacinth at Mandiri Arts Crafts. This system helps Mandiri Crafts to update the marketing system for handicrafts from water hyacinth, which is still done manually, so it is inefficient and far from the reach of the public, and its products are still limited to being online-based. This system consists of a system for inputting handicrafts, a system for marketing handicrafts, and preparing reports. The results of this study indicate that the design of an online-based handicraft product marketing information system can help Mandiri Seni Crafts in marketing its products outside the region and facilitate the delivery of information to customers. The study this using Hypertext Preprocessor or only PHP is a language script with function especially general _ used for web development. As well as using MySQL, which is a database management system that is useful for managing databases on websites that will later become data storage areas [ABSTRACT FROM AUTHOR]

Kerambitan District is one of the pioneers of tourism that has contributed to raising the name of Bali in the international community. However, so far the planning and implementation of tourism activities have not accommodated the integrated tourism aspects and disaster-safe tourism services. In fact, most tourist destinations in Kerambitan are dominated by natural tourism with hilly contours, which are included in areas prone to extreme weather disasters and areas prone to flooding and landslides during high-intensity rainfall. This study aims to build an early warning system based on digital application, to help create a disaster-safe tourist village. The Waterfall Method is used in development process. This application is Android-based, and integrating the Google Firebase Cloud Messaging feature for sending messages and notifications to various Android devices. The results of this study are an SIGADis E-tourism application, which in addition to display and promote tourist location information in Kerambitan, also has safe and disaster-responsive features including the early warning system feature through messages and notifications, information list of disasters that have occurred, disaster's distribution map and the weather information each tourist location that combined with Balinese lunar calendar (Sasih). Based on the application testing results using BlackBox Testing and Beta Testing methods, the application has been running according to the desired function, able to provide information about tourism village in Kerambitam, also provide disaster messages and notifications to various android devices, and able to display disaster distribution maps and suggestions related to the disasters when bad weather or events occur. [ABSTRACT FROM AUTHOR]

Indonesia targets net zero emissions by 2060. Therefore, pyrolysis from biomass is a promising first step in the transportation fuels-making process. This study aims to investigate the pyrolysis oil and the charcoal produced from the pyrolysis process of oil palm fronds in a 40 L rotary drum reactor. These pyrolysis products can be used as raw materials for bio-fuel and bio-carbon black. The research methodology is to conduct experiments on the conversion of palm fronds into pyrolysis oil and charcoal with variations in heating rates and pyrolysis temperatures, and also with and without the use of heat carrier media (steel shots S330). Based on the experiment results, optimal heating is carried out at a temperature of 500˚C for 1 hour, where it produces the most pyrolysis oil at 37.0%, followed by 30.4% charcoal and 32.6% gas. This pyrolysis oil has a heating value of 16 MJ/kg, 38.3% water content and 38.2% Carbon, 8.8% Hydrogen, 52.0% Oxygen, and 0.1% Sulphur content. Meanwhile, the bio-char has a calorific value of 31 MJ/kg, with a fixed carbon content of 77.0%, volatile matter of 12.9% and ash content of 10.1%. Experiments with steel shots produced fine charcoal and coarse charcoal. The ash content of fine charcoal is 20.8%, greater than coarse charcoal by 6.9%, but coarse charcoal has a Carbon content of 80.7%, which is higher than fine charcoal by 68.2%. This causes the Higher Heating Value (HHV) of coarse charcoal of 30.8 MJ/kg to be greater than the HHV of fine charcoal of 25.7 MJ/kg. Those results are crucial, as those are the data needed to upgrade the pyrolysis oil into high-quality fuel and when processing the bio-char into carbon black, which is a high value-added material. [ABSTRACT FROM AUTHOR]

This study aims to determine the cause of scale formation in the T-115 oil well in the Tanjung Field and to provide a suitable chemical solution to prevent the same problem from occurring in other wells. Samples of scale and water formation were collected from the well and analyzed using x-ray diffraction (XRD), X-ray fluorescence, and cation and anion tests. Based on the results, the researchers designed a chemical solution to overcome the scale in the tubing. The implication of this study is to provide insights to the production team to prevent similar issues in other wells in the field and optimize production operations. [ABSTRACT FROM AUTHOR]

The purpose of this paper was to show a calculation simulation of the Weighted Product method integrated with the CSE-UCLA evaluation model in determining the best recommendations for decision support. There are four evaluation components of the CSE-UCLA model that are used as standards for evaluation, including system assessment, program planning, program implementation, program improvement, and program certification. In addition, there are 10 evaluation aspects are used as alternative recommendations. The process of determining the best recommendation was carried out by simulating the calculation of the Weighted Product method, which consists of five stages, including preliminary data preparation, weights normalization, Vector-S calculation, Vector-V calculation, and determination of recommendations based on ranking results. The simulation results of the Weighted Product method resulted in three aspects of the CSE- UCLA evaluation model which became the best recommendations with a preference value was 0.1008. Those aspects included: aspect-1, aspect-7, and aspect-10. This paper has a positive impact on developing the insight of evaluators and education observers about innovation. This innovation demonstrates the use of the Weighted Product method in the field of computer science that can be used in determining the evaluation aspects of the CSE-UCLA model which are the best recommendations for decision support. [ABSTRACT FROM AUTHOR]

This paper aims to show the similarities and differences between the two innovative evaluation models. The innovative evaluation models are called the CIPP–SAW and CIPP–WP evaluation models. The two evaluation models are models that combine an educational evaluation model called CIPP (Context–Input–Process–Product) with a decision support system method called SAW (Simple Additive Weighting) and WP (Weighted Product). The way to obtain the similarities and differences between those two innovative evaluation models through a calculation simulation approach of the two SAW and WP methods integrated with the CIPP model in determining the best recommendations. There are four evaluation aspects and four CIPP evaluation components that are used for the calculation simulation. The simulation results showed five similarities and two differences between the CIPP–SAW evaluation model and the CIPP–WP evaluation model. The impact of this paper on the field of education is to provide positive information to educational evaluators and education observers regarding the similarities and differences between the two innovative evaluation models that combine the educational evaluation model with the decision support system method. [ABSTRACT FROM AUTHOR]

The purpose of this research was to show the user interface design of the Amalgamation Evaluation Application Based on the Provus-Alkin-WP(Weighted Product) integrated Rwa Bhineda and determine the quality level of the application. This research was developed using the Borg & Gall model, which focused on the design phase, initial trial phase, and revision phase of initial trial results. The research location was carried out at several IT vocational schools in Bali. The subjects involved in the initial trial were 24 respondents, consisting of experts and evaluators. Data collection was obtained using a questionnaire consisting of 12 questions. The data analysis technique of the research results was carried out by comparing the initial trial results with the five's scale quality standards. The research results showed the user interface design was categorized as good by a percentage level of quality of 85.49%. The impact of this research on educational evaluators is to increase the knowledge of evaluators about the importance of user interface design as the initial foundation for realizing a good evaluation application, and ready to use. [ABSTRACT FROM AUTHOR]