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Lightning has always been a dangerous threat to the equipment of electric power systems consisting of: power plants, substations, transmission lines and distribution lines. Generally, overhead high-voltage transmission lines are exposed to lightning strikes. Therefore, the degree of protection against lightning is determined based on the degree of insulation of the equipment. To prevent damage to equipment due to lightning strikes, arresters are used. In this study, three arrester models were used as comparisons, namely. IEEE arrester model. The system was simulated using Alternative Transients Program (ATP) software. The results showed that the lightning rod was declared successful in protecting the transmission system, where the three lightning rods had a Margin Protection (MP) of arresters that reached 28%. In the simulation, it is known that the IEEE arrester successfully cut off the lightning current in the transmission system so that the transient overvoltage recorded on the transformer does not exceed the Basic Insulation Level ((BIL) trafo.  

Regency roads are local roads which do not include roads connecting the district capital to other districts, but their network is diverse as a link for local activities, namely connector roads between villages, between sub-districts, production center roads and environmental roads in residential areas. This research focuses on roads in Kaur Selatan District and Maje District, Kaur Regency, Bengkulu Province with a total length of 128.50 km with a total of 68 sections. There are several sub-district roads which are a road network that is integrated with national roads. In general, this road section is often used by various types of vehicles, from light to heavy vehicles. Utilization of roads that do not match their class and the influence of the weather climate in areas that are quite extreme result in landslides so that the road body becomes narrow and heavily damaged. As a result of damage to existing roads, community activities are hampered. The purpose of this research is to provide information to the Bengkulu Regency government in preparing priority planning, determining the type of pavement that is appropriate to the location of the road section and determining the calculation of the costs required. The results of research and calculations show that the cost required for road repairs is IDR. 70,788,844,000 for a period of 5 years. The priority scale consists of 17 sections with a cost of Rp. 57,541,204,000.

Technology has a very important role in creating quality human resources. In this case, technology also does not escape incoming and outgoing goods transactions, as happened with Dolphin Corp. Dolphin Corp is one of the printing companies in Jambi City which serves various types of printing, both small and large scale. The services provided by Dolphin Corp, such as printing invitations, books, calendars, food packaging, brochures, magazines and so on, are all carried out based on requests from consumers after the consumer makes payment. The system used to store data on incoming goods still uses physical records in books, where there is no system that functions optimally to increase the amount of stock, reduce the amount of stock and record stock reports.

As a company engaged in ports such as ship services, goods services, container services, passenger services, and various services related to the port and shipping industry, of course, prioritizing good service. Various activities in the work environment have potential risks that must be identified and evaluated. Systematic, thorough, and structured approaches such as Hazard Identification, Risk Assessment, and Determine Control or HIRADC are used to identify problems affecting work processes and risks associated with existing equipment or systems, which can endanger individuals around the port. This research was conducted qualitatively by analyzing the safety risks of workers at ports around Surabaya, East Java. The results showed that there were 7 types of work with 45 hazard risks identified.

This research uses the Support Vector Machine (SVM) algorithm to predict Persebaya Surabaya's ranking in BRI Liga 1. The data used includes goals scored, goals given away, total end-of-season points, and status as champions. The results of the analysis using Orange software show that Persebaya Surabaya does not necessarily become a champion if it has a point value of 42 and an SVM value of 41. To become a champion, Persebaya Surabaya must score 69 points or more in a season and achieve an average of more than 54 goals per season. The suggestion of this research is to have more data so that the results of data processing using Orange software are more optimal and accuracy is more precise.

This research aims to determine the effect of adding the additive Sika Fume on the compressive strength of hollow concrete. This research uses a type of quantitative research with experimental methods, namely by carrying out several tests on test objects in the laboratory. The results of this research show that the compressive strength of hollow concrete with the addition of sika fume with a variation of 0% and 2% of the weight of cement, the experimental results obtained for the compressive strength of hollow concrete for 28 days of concrete with a variation of 0% with an average of 16.83 Mpa. For a variation of 2% with an average of 17.42 Mpa. So it can be concluded that concrete with a variation of 2% with an average of 17.42 Mpa is the variation with the highest compressive strength value and reaches the design compressive strength. Meanwhile, the 0% variation with an average of 16.83 Mpa is the lowest compressive strength value and does not reach the design compressive strength.

The inventory problem that still occurs at PT Indonesia Plafon Semesta is the accumulation of resin and calcium raw materials which results in considerable losses. PT Indofon began to experience a buildup of resin raw materials in August amounting to 16,100Kg and for calcium amounting to 15,200Kg so that each month it soared until its peak in October, namely a buildup of 23,500Kg of resin, and 23,200Kg of calcium. The use of the right method for inventory control problems is Just In Time , which is a management strategy used to optimize the production process and product delivery by buying and producing only when needed and at the right time. Silver Meal Heuristic, a heuristic approach used in inventory control to determine the optimal lot size. The quantity of raw material orders using JIT is relatively more than the silver meal, but with JIT the supplier only needs to send 4-5 times, meaning that the company can save costs. The quantity and frequency obtained from data processing using silver meal is more optimal. However, the cost of raw material inventory incurred is quite large. For a decrease in efficiency costs by implementing a policy of making purchases with Just In Time  (JIT) and is expected to save on raw material inventory costs. So that these cost savings can be allocated by the company to other costs.

Rock mass is a volume of rock consisting of rock material in the form of minerals, texture, composition and also consisting of discontinuous planes, forming a material and interconnected with all elements as a unit. The rock mass itself is composed of several intact rocks which basically have isotropic, continuous and homogeneous properties. However, the conditions found in the field are different, namely anisotropic, discontinuous and heterogeneous. These properties will certainly influence the test results in the uniaxial test. There are several factors that influence the results of uniaxial rock tests, one of which is the scale effect. The purpose of this test is to determine and analyze the effect of rock sample size on the uniaxial compressive strength value of claystone. This rock testing was carried out at the Mineral and Coal Technology Laboratory and the rock sampling locations were in Palaran District, Samarinda City and in North Samarinda District, Samarinda City. In this uniaxial compressive strength test, 3 side widths with different lengths will be used. After carrying out the uniaxial compressive strength test, the average uniaxial compressive strength test value was obtained in each formation, such as the Balang Island formation, the average rock compressive strength test value was 1.68 Mpa and the Balang formation, the average rock compressive strength test value was 3.10. Mpa. Based on these results, it can be concluded that the larger the sample size, the smaller the rock compressive strength test value tends to be.      

Idle time or disturbing time is time wasted while the ship is moored is a classic problem that has not been solved in Indonesia. Tanjung Emas Port is the busiest port in Semarang City, Central Java, which is a stopover center for providers of sea transportation facilities and infrastructure in the context of loading and unloading means the transfer of cargo from and onto ships to be stockpiled into or directly transported to the place of the owner of the goods through the port dock using loading and unloading complementary equipment. This study aims to determine the effect of port services, ship engine tools, and loading and unloading productivity, on Idle Time at Tanjung Emas Port Semarang. The population in this study were ship crews from the deck departement division and the sample used in this study was 119 respondents. And do not use the sampling technique because the number of samples is the same as the population, then the data is analyzed using multiple liniar regression with the help of (software) Statistical Package (SPSS) Version 26. The formulation of the regression in this study is as follows: Y= 0,597 + 0,368X1 + 0,356X2 + 0,213X3 + m. From this equation it is know that the most dominant variable influencing Idle Time is the port Service variable with a regression coeffient of 0.368. The R2 test ( R The ) obtained a result of 0.443 or 44.3%, which means that Idle Time is influenced by the variable port Services, Loading and Unloadng Speed, and Ship Machinery Equipment which is equal to 44,3% and other factors that affect Idle Time Tanjung Emas Port Semarang, namely 100%.

Sweet arum mango is one type of mango which when harvested has the highest vitamin C content of 7.53 ± 0.4 mg / 100 g. Processed sweet arum mango fruit products that have the potential to be developed are in the form of fruit juice. This is a consideration for researchers to conduct further research on the addition of eugenol preservatives with different concentrations of preservatives and storage times to produce better mango juice. Eugenol compounds have pharmacological activities as analgesics, anti-inflammatory, antimicrobial, antifungal, antiseptic, stimulant, so these compounds are widely used in the pharmaceutical industry. Based on the experimental results, optimal conditions for the use of eugenol occurred until day 2, where the addition of eugenol with treatment 3 as much as 1 ml amounted to 38.82% better when compared to other variations of eugenol addition.  The addition of eugenol preservatives cannot preserve the content of vitamin C in sweet mango juice even the content of vitamin C tends to decrease. Sweet arum mango juice has a shelf life of 12 days and total dissolved solids of more than 20%, so the resulting fruit juice does not meet SNI 7382:2009.

Electric Vehicles are vehicles that operate entirely or partially on electric motors, utilizing electrical energy stored in batteries or other rechargeable energy storage sources. The increasing use of electric vehicles also brings potential risks of new types of accidents, different from those associated with conventional internal combustion engine vehicles. Therefore, there is an urgent need to provide accurate information and appropriate handling related to electric vehicle technology, including hazard potential assessment, optimization of firefighting basics, selection of suitable firefighting agents, and the development of electric vehicle firefighting application methods. This study aims to understand the handling of electric vehicle fires using a literature review method on 10 research articles. The results show that 6 studies used water as a firefighting agent either alone or in combination with other agents such as CO2, C₆F₁₂O, liquid nitrogen, foam, and fire blankets, making it more effective in extinguishing electric vehicle fires. However, one study does not recommend using water due to its environmental impact when extinguishing electric vehicle fires. The research findings indicate the need for further innovation and research in safety technology and firefighting for electric vehicles.

Pelayaran Semesta Sejahtera Lestari Belawan is a company that operates as a shipping agency (ship agency) which provides domestic and international services. The process of handling ship departure (clearance out) at PT. The Semesta Sejahtera Lestari Belawan voyage starts when the ship has finished carrying out activities at the port, the agent makes another request for ship departure or Clearance Out. The Clearance Out process is a maximum of six hours before the ship leaves, the agent submits a ship out service in the Inaportnet system. To issue an SPB (Sailing Approval Letter), the agent must complete all documents and costs which are the agent's responsibility. For the issuance of an SPK (Work Order), guide the ship out no later than one hour after the SPB (Sailing Approval Letter) is issued. After processing the SPB (Sailing Approval Letter) is complete, the agent will take the ship documents and SIB (Sailing Permit) at KSOP. PT Pelayaran Semesta Sejahtera Lestari is a company that operates in the service and agency services sector, in other words a representative of the general agent/principle to take care of ship documents and take care of all ship needs that are needed when the ship is at the port. To obtain data, the author used field research and library research methods.

The aim of this research is to analyze the effect of adding hyperplasticizer and retarder on the compressive strength of self-compacting concrete. Fine aggregate and coarse aggregate from the Jenneberang River, Kab. Gowa. The concrete mix design uses a trial and error mix design for self-compacting concrete by making visual observations, so that the physical conditions of the mixture appear to be sufficient to produce a good mix. The stages of this research, by finding a comparison of the slump flow values ​​of the self-compacting Concrete concrete, then making test objects, after that curing the test objects using the water curing method for 28 days, then testing the compressive strength of the self-compacting Concrete concrete to produce comparison to the compressive strength of normal(conventional) concrete. The results of this research show that self-compacting concrete has a compressive strength value of 46.25 Mpa compared to normal concrete of 45.02 Mpa, an increase of 2.73% compared to normal concrete. And the slump value of normal concrete is 8 - 13 cm, while the slump flow of self-compacting concrete is 63 - 84.9 cm, with a time range between 2.53 - 3.46 seconds, able to reach a diameter of 500 mm on the segregation board.  

Indonesia is one of the countries that has a fairly high level of natural disaster vulnerability. Mount Sinabung is a strato-type volcano. Administratively, Mount Sinabung is in the Karo Regency, North Sumatra. The eruption of Mount Sinabung has had a very significant physical, psychological and social impact on society. In facing a disaster, survivors need to survive and continue living. The ability to adapt to conditions after experiencing a traumatic event is called resilience. People who lost their homes due to the eruption of Mount Sinabung must be willing to be relocated to new, safer places such as permanent Shelter. Researchers want to see how disaster survivors in the Siosar Permanent Residence respond to being able to recover or recover from their previous situation. The method used in this research is descriptive qualitative with a case study approach. Data collection techniques were carried out using interviews/FGD, observation and documentation studies. The research results show that there are still teenagers who are not yet fully resilient. Researchers found teenagers who have not been able to recover from the problems they faced after the eruption of Mount Sinabung. Therefore, support from various parties or the pentahelix (government, academics, business world, society and mass media) is needed to build sustainable resilience in Siosar Permanent Shelter.

To support green energy and reduce the effects of greenhouse gases, it is necessary to conceptualize and explore the use of renewable energy. In this research, the use of new renewable energy, especially photovoltaics (PV), will be applied to educational buildings, especially at ITS PKU Muhammadiyah Surakarta. This system is intended to reduce the use of conventional electrical energy. This system will be installed on the roofs of campus buildings with installation plans to meet the power requirement of 4.8 kW. This photovoltaic (PV) system will be modeled to determine the number of PV panels needed. Based on the simulation results, the number of panels required is 36 panels (2 series, 18 parallel) to produce 4.85kWh of power. Modeling and analysis of this system was carried out using RETScreen and MATLAB SIMULINK software.

Regular and effective maintenance at Airport Rescue & Fire Fighting (ARFF) at Syamsudin Noor Airport in Banjarmasin is very important to maintain the performance and reliability of the system. However, the maintenance process is often still carried out manually or using less efficient methods. Therefore, this research aims to develop a web-based ARFF maintenance application that can increase the efficiency and effectiveness of the maintenance process. From the results of research on the development of the Web-based Syamsudin Noor Banjarmasin Airport Maintenance Airport Rescue & Fire Fighting (Arff) application, conclusions can be drawn in the form of making it easier for officers/admins to search and present actual information. Makes it easier to create monthly or annual reports that include all reports that can be done efficiently. 

This paper aims to find out the process of managing export and import documents by PT Adhigana Pratama Mulya Belawan branch, the process starts from before the arrival of the ship to the port of Belawan, the agent has prepared the documents needed by the ship in loading and unloading activities. The data collection method used by the author in writing this paper is the field observation method (field research) and the library method (library research) to find out more closely how the company PT. Adhigana Pratama Mulya Belawan branch in carrying out export and import document management activities. The problems faced in the process of managing export and import documents are frequent quantity differences that cause revisions to documents. Good cooperation and coordination between shipping companies and related agencies in the management of export and import documents is needed for the smooth service of handling export and import documents

To find out more closely how the company PT Admiral Lines Belawan Branch, carrying out shipping activities in the issuance of Outward Manifest in the Customs online system, this aims to carry out responsibilities in submitting cargo reporting documents to parties that are truly related and responsible. As for the completeness of customs documents to support and expedite the Outward Manifest issuance procedure. as for the obstacles in the Outward Manifest issuance process that make it difficult to issue the Ouward Manifest, which the company can overcome seriously so that the company does not experience losses caused by a staff in submitting online data. With the Manifest Module online system, it is easier to manage Outward Manifest documents that train staff to be more thorough. This paper uses 2 (two) types of research methods, namely: the Field Observation method (Flied Reseach), interviews with employees and the Heritage Study Method (Library Reseach), namely taking data from library books.

Of course, a soccer field needs water and the fertility of the field soil so that the grass can grow. The development of science and technology currently has a big influence on getting work done. A pump is a tool used to move liquids (fluids) from one place to another through pipes (channels) by adding energy to the fluid being moved and continuing continuously. Currently, many water pumps still use the manual method, namely using a switch or even just using a plug. Grass will also live if the soil has appropriate humidity, if the soil moisture level is low, the grass will die if there is excess moisture and it will not be able to grow. This problem certainly requires a solution that can help monitor soil moisture as well as control water pumps. By utilizing NodeMCU ESP8266 microcontroller technology as the control center, the YL-69 sensor measures soil moisture values ​​and also relays as a replacement for manual switches. To control pump conditions via Blynk.

One of the intersections in the city of Palembang is the Three-way Intersection of Bukit Siguntang, which is a signal-free intersection. This intersection is located in an educational and residential area, connecting Srijaya Negara Street and Demang Lebar Daun Street. The road has a very high volume of vehicles, with traffic flows reaching 45,208 vehicles on Sundays or holidays, 82,124 vehicles on Mondays, and 80,379 vehicles on Wednesdays. Among these three days, Monday is the busiest day with a vehicle count of 84,364. The intersection's performance is evaluated by examining the capacity levels at each approach. The Three-way Intersection of Bukit Siguntang shows a degree of saturation (DS) above 0.85 on all approaches, indicating that the road capacity has reached a saturation level resulting in a service level of D for the intersection, with an average intersection delay of 34.27 seconds/vehicle. To enhance the intersection capacity, several alternatives can be implemented, including road geometric widening and changing the traffic flow policy from two-way single lane to one-way single lane. Simulation of the capacity improvement for the intersection with both alternatives indicates that road geometric widening results in a delay of 24.58 seconds/vehicle, falling within the service level C for the intersection. Meanwhile, changing the traffic flow policy from two-way single lane to one-way single lane results in a delay of 17.39 seconds/vehicle, also falling within the service level C for the intersection.