bluuebunny/crossref_metadata_2025 huggingface dataset:
Selbukassa - A Case Study for Aiming at Low Emission Buildings through Extensive Reuse of Materials
Authors: Plavina A , Gruner M
Published: October 2019

Recent reports from UN International Resource Panel call for double decoupling – decoupling of material use and related environmental impacts from economic growth. The construction and use of buildings constitute a significant portion of energy use, GHG emissions and extraction of materials in Europe. One of the central strategies addressing double decoupling in the construction industry is reuse and recycling of building materials and components that would limit raw material extraction and embodied emissions related to new products. A recent IPCC report states the urgency of limiting GHG emissions already by 2030 to remain below the 1.5-degree target. Given this timeframe, reducing emissions in the early stages of a buildings lifetime appears worth considering, meaning prioritizing embodied over operational emissions. The case study used for this article is an ongoing building project “Selbukassa” (“the Selbu box”) situated in Svartlamon – an experimental neighbourhood for urban ecology in Trondheim, Norway. It is a bottom-up, self-build project with a strong focus on reuse of materials. The 300 m2 building will house 4 families and is built reusing an old log house, as well as CLT-elements from a former pavilion used for exhibiting an art piece by the local artist Killi Olsen. Other salvaged materials and components include windows, doors, roof slate and most of the internal and external finishes. Due to the experimental status of the area and to allow for reuse of building components with lower energy performance, the fulfilment of energy requirements in the building code TEK 17 was not required by the local building authorities. The article examines the embodied and operational emissions of Selbukassa, and compares it with a reference building with no reused components and complying with energy requirements in the building code TEK17. Simien v.6.009 is used for energy simulations of the two cases, and LCA tool One Click LCA Norge for NS 3720:2018 with data sourced from Norwegian and other European EPDs is used for estimating embodied emissions. The article investigates the possible savings in emissions linked to reuse of materials, as well as the trade-offs between reused components with worse energy performance and the consequential higher energy demand. The article contributes to the discussion about the various implications of reuse of materials and more generally on how the built environment could respond more optimally to a combined emission and resource use reduction challenge.
Techniques for airflow measurements to determine the real efficiency of heat recovery in ventilation systems
Authors: Rønneseth Øystein , Liu Peng , Justo-Alonso Maria , Mathisen Hans Martin
Published: October 2019

Heat recovery in ventilation is essential to reduce energy use and thus mitigate greenhouse gas emissions from the building sector. Heat recovery efficiency of at least 80 % in new buildings is required according to Norwegian standards. However, measurements show that the real heat recovery efficiency during operation is commonly 10-20 % lower. Measuring heat recovery efficiency in buildings is challenging, mainly due to difficulties measuring airflow rates close to the air handling unit (AHU). This study assesses the following duct airflow measurement techniques and equipment: pressure differential, velocity traversal technique, ultrasound and tracer gas. The pressure differential method can provide accurate flow rates and thus it is used as the reference measurement. However, it is not suitable for duct flow measurements due to its high pressure penalty and long straight duct requirement. Velocity traverse and tracer gas methods introduce less disturbance to the flow. Nevertheless, both methods require intensive labour work and cannot track quick changes of the airflow with time. The application of ultrasound to measure airflow is relatively novel and it can automatically measure constant and fluctuating airflows with low pressure drop and acceptable accuracy when the proper installation and minimum straight duct are provided.
Analysis of Harmonic Effect of Photovoltaic Integration into Medium Power System
Authors: Apriansyah M E , Ramadhan U F , Aryani D R , Utomo A R
Published: October 2019

Renewable Energy is starting to grow rapidly, the use of solar energy in Indonesia has a good development. According to the grid code issued by the national utility company, the maximum standard harmonic limit is 5%. Harmonic is mostly caused by non-linear loads that form a distorted sine wave, which leads the equipment to become hotter faster, adding losses and reducing the equipment lifetime. The simulation method uses ETAP software to obtain values from Total Harmonic Distortion (THD) on the 20kV and 150 kV Beta substations sides with several scenario simulations of photovoltaic power plant integration with a capacity from 5 to 20 MWp with multiple of 5. The simulation results have shown that the maximum THDv value in the scenario at 20 kV Beta substation is 0.26% and at 150kV Beta substation is 0.1%. This value is still below the standard limit, so by the integration of PV plant, system still operates securely.
Study of Battery Sizing for Solar Power Plant
Authors: Bangun G M , Nabila N , Budiansyah M A , Alvianingsih G , Utomo A R
Published: October 2019

Photovoltaic is one of the products of renewable energy-based electrical energy generation technology, without using fossil fuels, even without mechanical movements in the energy conversion process. Photovoltaic depends only on photons from solar rays. The sensitivity is relatively high against the sun’s irradiance, so because of that, both the output voltage and current become unstable. However, the instability of photovoltaic in producing electricity needs to be fixed by adding power storage component, such as batteries. The purpose of this paper is to design an optimal system to measure the size of the battery in Solar Power Plant. The best sizing battery is 80MW with 194 cells.
Optimization of Rooftop Area on Building K Faculty of Engineering Universitas Indonesia for Grid-Connected PV
Authors: Bimantoro H , Ardita I M , Jufri F H , Husnayain F
Published: October 2019

This study aims to design and assess the simulation of the On-Grid PV System that will be implemented in Building K at the Faculty of Engineering, Universitas Indonesia (FTUI), Depok, West Java. In addition, this research is also to find out the amount of energy potential and issued by the 66 kW PLTS On-Grid design and its energy saving value. On-Grid PV System was designed and simulated by PVsyst and the results were analyzed. Load profile data from Building K FTUI are used. The simulation shows that the energy produced by PV is 97,889 MWh per year, the performance ratio is 82% with the contribution rate to Building K is 23.79% in a year, and the reduction in energy consumption from utilities is 19.48% during workdays and 49.01% during the weekend.
An explicit model of temperature-dependent thermal conductivity for nanofluids
Authors: Tiandho Y , Afriani F , Puriza M Y
Published: October 2019

Nanofluids is a material that has good prospects to increase the efficiency of the heat transfer process. With the addition of small fraction nanoparticles, the thermal conductivity of the nanofluids can increase significantly compared to the fluid base. Although it has excellent application prospects, the study of thermal conductivity models is still a problem. The uniqueness of the characteristics and rapid development of nanofluids experiments make the proposed model continue to undergo validation testing. In this paper, a model of temperature-dependent the effective thermal conductivity of nanofluids is proposed. This model is a development of a previously proposed model that only involves aspects of the fraction of the volume and diameter of nanoparticles. The model construction comes from the modification of the model proposed by Mintsa-Roy-Nguyen-Doucet, which is equipped with aspects of the nano-convection mechanism as proposed by Jang-Choi.
The Adsorption Efficiency of Iron from Post-Tin Mining Water using Nanomagnetic Fe3O4/Chitosan Portunus pelagicus shells
Authors: Julianti E , Samsiar A , Siregar R N , Fabiani V A
Published: October 2019

Adsorption was carried out on the water of post tin mining using nanomagnetic Fe3O4/chitosan from Portunus pelagicus shells. Nanomagnetic Fe3O4/Chitosan was prepared for iron adsorption. The nanomagnetic Fe3O4 was characterized through XRD and chitosan was characterized through FTIR The concentration of Fe in post tin mining water is 6.1 ppm. This study varied the mass of Fe3O4 and stirring time. The adsorption results were analyzed by AAS and obtained the largest adsorption efficiency (96.72%) at stirring 30 minutes with a mass of Fe3O4 of 120 mg.
Water Quality Testing Due to Oil Palm Plantation Activities in Bangka Regency
Authors: Sari F I P , Mahardika R G , Roanisca O
Published: October 2019

Agricultural activities are one of the main income sources in Bangka Regency, but this activity also provides a dilemma for environmental conservation. Oil palm plantation activities always use fertilizers and pesticides, leaving organic contamination in the waters. Cases of poisoning against pesticides, especially organophosphate groups, have been widely reported. To avoid that preventive measures are required, so we must know the water quality and pollution load that contained in the water around the area of oil palm plantations. This study aims to monitor water quality based on chemical parameters (DO, BOD, COD, nitrate and phosphate levels), and the presence of pesticide residues in the waters around oil palm plantations in Bangka Regency. The results showed waters around oil palm plantations in Zed meet mild to moderate pollution (3.21-4.95 mg/L) based on DO parameters, meet class II water quality standards for BOD (2.37-2.68 mg/L), COD criteria (8.7-11.4 mg/L), nitrate (0.985 mg/L) and phosphate (<0.0313 mg/L). Waters around oil palm plantations in Sempan meet moderate pollution based on DO parameters (3.59-3.78 mg/L), and meeting the class II water quality standards for the criteria of BOD(2.37-2.47 mg/L), COD (8.68-9.56 mg/L), nitrate and phosphate. The results did not found any pesticide organophosphate residue.
Application of Mulch and Palm Oil Waste as Bioremediation Agents in Post Mining Land
Authors: Yarda V R D , Lestari T , Pratama D
Published: October 2019

Post-tin mining land in Bangka Island can be utilized by application of mulch and nutrient from organic material to stimulate plant growth. The aims of this study is to know the effect of mulch and palm oil waste to stimulate growth of mustard. The research was conducted in Post-Tin Mining, Bangka, from December 2018 to May 2019. This study used Factorial Randomized Block Design with two factors. The first factor was application of mulch consisted of without (M0) and application of mulch (M1). The second factor was application of palm oil waste consisted of empty palm fruit bunch (T1), empty palm fruit bunch + cow manure + Effective Microorganism-4 (T2) and empty palm fruit bunch + palm bunch ash (T3). The result of variance analysis showed that mulch and palm oil waste gave significant effect on all parameter except ash content. Mulch gave the highest result than without mulch, and empty palm fruit bunch + cow manure + effective microorganism-4 gave the highest result than the other treatment. Interaction between mulch and empty palm fruit bunch + cow manure + effective microorganism-4 gave the best result and could be a profitable solution to stimulate the growth of mustard.
Feasibility Study on The Operation of Toboali Substation to Reduce The Use of Fossil Fuels as Power Plants and Energy Loss by Computer Simulation
Authors: Khoirun  , Asmar  , Puriza M Y , Kurniawan R , Tiandho Y , Siregar E M
Published: October 2019

This study discussed the analysis of load flow before and after the Toboali Substation (GI Toboali) - that is still in development process stage when the paper is written-. This study was operated in a computer simulation using ETAP Software. The Toboali substation needs to be built because Toboali diesel power plant will be shut down because the Toboali diesel power plant is a diesel power plant leased from PT. Megapower. From the simulation results it was found that before the Toboali substation operated the energy loss was 3,895.7 MWh/year and after the Toboali Substation operated an energy loss was 3,377.5 MWh/year and will reduce 20 tons/day usage of biodiesel. It is expected that when the Toboali substation operates it will reduce the energy loss and electricity dependence of the region on fossil energi and also it will increase power system reliability.
Net Social Impact of Illegal Unconventional Onshore Tin Mining in South Bangka, Bangka Island
Authors: Sulista
Published: October 2019

Various economic, social, and environmental costs and benefits in illegal unconventional tin mining in Bangka Island have not been mapped clearly. The objective of this study is to obtain information on the economic, social, and environmental costs and benefits incurred by these mining activities expressed in monetary terms. The researcher conducted a field research in three mine villages and interviewed the miners, village government apparatus, and community leaders to map the impacts in the area. The benefits are the income and the growth of sales business, while the incurred costs include the flow of cash towards investors outside the village and the cost of river revitalization, land reclamation, watershed rehabilitation, and flood emergency response. Limited disclosure of data by the mining community and the lack of data available have yielded little cost benefit calculation. Net Present Value (NPV) approach was used to measure net social impact by assessing the profitability of mining, its benefits for the mining community, and the losses incurred by cost of investors and land reclamation. The results of calculation were positive, suggesting that unconventional mining had a significant economic impact at the local level. However, there needs to be further cost analysis of broader environmental damages.
The utilization of hydroxylsodalite synthesized from coal fly ash for zinc removal in acid mine drainage
Authors: Hidayat A E , Moersidik S S , Adityosulindro S
Published: October 2019

One of the alternative solution to reduce ash waste in landfills is by utilizing coal fly ash for the removal of metal ion in wastewater, especially acid mine drainage (AMD). In this study, zeolite was synthesized from coal fly ash using a two-step method, hydrothermal and fusion method. The coal fly ash and the zeolite product were characterized physically and were used for the removal of Zn2+ in AMD. The adsorption experiment was carried out using batch method in synthetic AMD solution to study the influential parameters such as adsorbent dosage, contact time, adsorbent isotherms and kinetics. The zeolite synthesized in this study resulting hydroxylsodalite zeolite type, which increases the surface area. It was revealed from the adsorption experiment that the removal efficiency of Zn2+ was 93.47% under the conditions of pH ± 3, initial concentration Zn2+ 100 ppm, optimum contact time 120 minutes, and adsorbent dose 6 g/L. Furthermore, the Langmuir isotherm model and the kinetics model of pseudo-second-order fitted the adsorption data better, with the maximum sorption capacity of 27.32 mg/g. The result of this study indicate hydroxylsodalite synthesized from coal fly ash has great potential as an economical and sustainable material for the removal of metal ion Zn2+ in wastewater.
Erosion Hazard Classification Analysis in Kantung the Watershed, Bangka District
Authors: Hisyam E S , Fahriani F
Published: October 2019

Watersheds in the Bangka Belitung Islands Province are increasingly experiencing environmental damage from year to year. Location of the Kantung Watershed in Parit padang Sungailiat Bangka Village. The causes of damage to this watershed are mining activities, land use changes that were previously forested as residences and agricultural land that is not managed properly so that the impact is reduced forest as a natural protector, erodible soil or erosion. The method of analysis carried out in this study is the USLE (Universal Soil Loss Equation) approach. Based on the analysis that has been carried out by the USLE method, the total erosion size of the Kantung watershed is 521,684 tons / ha / year 3,140,190,871 tons / year / year with Class V (Very Heavy) erosion hazard classification. Based on the results of the erosion hazard classification obtained is class V (Very Heavy), with large erodibility, the slope of the dominant slope is very steep, changes in land cover especially for mining activities, residences and agricultural land without management, the recommendations for reducing erosion are mechanical and vegetative soil conservation methods
Stress Analysis and Safety Factor of Shaft on Pepper Peeler Machine to Reduce Environmental Pollution
Authors: Rosa F , Rodiawan  , Prayitnoadi R P
Published: October 2019

Manually, pepper peeling uses water flowing in the river for 8-14 days that cause the river to become polluted by pepper peel and cause a bad smell. A pepper peeling machine is a tool to peeling pepper that has a system using two dishes consisting of a fixed top dish and a rotating bottom dish. A shaft is used to rotate the bottom dish with 14.58 rpm rotation, and it requires 1 kW electric motor with 1400 rpm rotation that is transmitted by reducer ratio of 23.3:1 and a bevel gear ratio of 1.6: 1. The shaft must be analyzed to determine its ability where the material is carbon steel material that has yield strength 350 MPa and is supported by two angular contact bearings which function as pin constraints and frictionless constraints. The shaft was analyzed using stress analysis with static analysis method using Autodesk Inventor Version 2019 software. Based on the analysis results, a minimum von mises stress of the shaft is 0.00 MPa and a maximum of 826.57 MPa on the diameter of 25 mm, minimum safety factors of 0.42 on the diameter of 25 mm and a maximum of 15. In Von-Mises stress and safety factor, the diameter of a shaft is not strong enough to withstand the load. To be able to meet the determined yield strength with a minimum safety factor of 1, the minimum diameter needed is 34.05 mm with a safety factor of 1.1. Using this machine, pepper peeling that done in the river can reduce river pollution.
Design Information System of Small Island in Bangka Belitung Archipelago Province
Authors: Putra G B , Atmaja E J J
Published: October 2019

Bangka Belitung Archipelago Province is one of the few provinces in Indonesia that has nomenclature of archipelago province in Indonesia. Archipelago Province means that the provinces have fewer land areas compare to sea areas. The Bangka Belitung Archipelago Province has many small islands is about 470 islands that have names, and the rest, 480 islands, that doesn’t have name. Information technology are believed to be able to answer a number of obstacles and problems that found on those small islands. The use of information technology by design information system for the small island is to make ease manage the information about the island and development planning of the potency of those island and in order to collect data on island in Bangka Belitung so planning and development for those island can carried out in the future, especially economic and tourism. This information system provide information on small islands and their potency and sea lanes can be used when they want to visit the island in Bangka Belitung. The system can be access using computer and smartphone through Internet to make it easier to get information about small islands and detail information when visiting the island in Bangka Belitung
Evaluation of pedestrian facilities to improve the pedestrian environment in The Central Market of Pangkalpinang
Authors: Safitri R , Amelia R
Published: October 2019

Plaza Pangkalpinang – Bangka Trade Center Area as The Central Market of Pangkalpinang, generates a large number of trips. The trips are not only vehicle trips but also trips of the pedestrian. The high pedestrian traffic requires pedestrian facilities. The availability of pedestrian facilities will affect the pedestrian environment. The pedestrian-friendly environment will encourage people to walk more. This study aims to assess pedestrian facilities to improve the pedestrian environment in Plaza Pangkalpinang – Bangka Trade Center Area. Pedestrian facilities are evaluated based on the walkability index. In this study, the area is divided into 2 zones, followed by determining the pedestrian routes in each zone. All of the pedestrian routes are divided into 16 road segments. Then, the walkability index will be assessed using 9 parameters in each road segment. The research finding shows that Plaza Pangkalpinang – Bangka Trade Center Area is in bad condition for walking and not pedestrian-friendly. The walkability index in this area is 49.17. It means the available pedestrian facilities are not good enough for walking. Furthermore, the result can be used as a consideration of the government for increasing pedestrian facilities to improve the pedestrian environment in Plaza Pangkalpinang – Bangka Trade Center Area.
Chitin Deacetylation Shells of Portunus pelagicus L. Using Microwave Irradiation
Authors: Mahardika R G , Jumnahdi M , Widyaningrum Y
Published: October 2019

Natural polymers such as chitosan are one of the interesting things to study or are widely used as industrial raw materials such as adsorbents, membranes, and edible films. Portunus pelagicus L. is one of the sources of chitosan from nature. The shell of Portunus pelagicus L. in Bangka Island are waste from the untapped food industry. Even though this shell can have high values because there are chitin and chitosan. Good chitosan has a high degree of deacetylation. So the research purpose of this study is to see the effect deacetylation process using a microwave. The microwave used was MARS 6 - Microwave Accelerated Reaction System (CEM) using an EasyPrep Plus vessel. Various in Microwave deacetylation process is the time at 1200 W and 100°C. The method for analyzing the structure and degree of deacetylation (DD) in this study uses Fourier Transform Infrared (FTIR) spectroscopy. The results showed that deacetylation using conventional methods for 120 minutes at a temperature 100°C had DD 76.67% while deacetylation using microwave for 40 minutes at a temperature of 100°C had a DD 77.89%. Microwave deacetylation is three times faster than conventional methods.
The Effect of Particle Size on the Performance of Electrode Supercapacitor based on Pepper (Pipper Nigrum) Shell Activated Carbon
Authors: Kurniawan W B , Indriawati A , Marina D
Published: October 2019

The synthesis of pepper shell activated carbon-based supercapacitor electrodes to determine the effect of particle size on electrode performance has been done. The pepper shell activated carbon was synthesized using HCl activator with a ratio of 1: 4 (W/V) and then activated physically in an inert condition at 6000C. The characteristics of activated carbon samples were carried out using SEM and BET. SEM results show that carbon has a porous morphology with radius size of absorption pores of 130.0 nm and 121.9 nm respectively for particle size samples of 74 microns and 149 microns. The results of cyclic voltammetry (CV) to find out the value of specific capacitance at a scan rate of 50 mV/s showed an amount of 0.037 F/g and 0.0075 F/g for samples 74 and 149 microns. The results showed the influence of particle size on the performance of supercapacitor electrodes.
Use of Gypsum Waste and Tin Tailings as Stabilization Materials for Clay to Improve Quality of Subgrade
Authors: Apriyanti Y , Fahriani F , Fauzan H
Published: October 2019

Clay is a soil with low stability, so an effort is needed to improve soil stability in order to improve the quality of subgrade. In this study, an effort was made to improve soil stability by adding gypsum waste and tin tailings as a mixture in clay. Gypsum waste and tin tailings have not been utilized optimally in Bangka Belitung Province, so the research needs to be done to determine the effect of using gypsum waste and tin tailings as a material for stability of clay. The tests of soil characteristics carried out in this study were sieve analysis, soil specific gravity, compaction and direct shear test. In this study, the addition of gypsum waste and tin tailings in soft soil with 4 variations, namely clay with additional 8% gypsum waste and 20% tin tailings, clay with additional 8% gypsum waste and 30% tin tailings, and clay with addition 8% gypsum waste and 40% tin tailing, besides that, testing of the original soil was also carried out. The results of sieve analysis test showed that the addition of gypsum waste and tin tailings to clay soils could change the gradation of clay. Addition of gypsum waste and tin tailings on clay soil increases cohesion (c) dan shear angel value so that increases soil shear strength. From the results of the study, the addition of gypsum waste and tin tailings can improve the stability of clay so Improve Quality of Subgrade.
Green-synthesis of CuO-doped SnO2 nanoparticles using pelawan (Tristaniopsis merguensis) leaf extract
Authors: Mustari  , Evi J. , Noor A , Rafsanjani R A , Tiandho Y
Published: October 2019

CuO-doped SnO2 nanoparticles were successfully synthesized using biosynthetic methods with the pelawan leaf extract. This method is a modification of the sol-gel process by utilizing antioxidant compounds from the leaf extract as a trap-matrix for tin oxides. This research was conducted based on variations in CuO doping. The characteristics of tin oxide observed in this study were a phase, crystallite size, and crystallinity, which determined based on x-ray diffraction method. It is expected that the method proposed in this study can be developed to synthesize SnO2 nanoparticles that are environmentally friendly.
The Sustainability of Photovoltaic System at Rawasari Village, Tanjung Jabung Timur through Student Community Service - Community Empowerment Learning Program
Authors: Aliyah F , Novitasari D , Budiarto R , Mahfud A
Published: October 2019

Rawasari is one of location at Tanjung Jabung Timur Regency that installed by photovoltaic system through Millenium Challenge Account Indonesia (MCAI) program by Konsorsium Energi Mandiri Lestari (KEMALA) in early 2018. The total installed photovoltaic system at Rawasari was 41.8 kWp which consisted of solar home system, solar system for public facilities, and solar system for business unit. When Kemala program ended in February 2018, the sustainability of the business unit was threatened because of there was not educated or skilled assistance that ensure photovoltaic system can run well. Therefore, the role of Student Community Service - Community Empowerment Learning Program (SCS-CEL) by Universitas Gadjah Mada (UGM) was deemed necessary to parse that problems. The SCS-CEL program has conducted from June-August 2018 that involved about 27 students from multidiscipline studies. Through two main programs of SCS-CEL namely strengthening the management system for photovoltaic and improving the quality and capacity of production business units. The result showed that an increasing of public awareness of the importance of maintaining a photovoltaic system and developing of drinking water business unit.
Environmental Risk Analysis Of Road Improvement In Tarakan City
Authors: Prihartanto E , Nawir D
Published: October 2019

The development of the Tarakan City Road network for coastal areas has increased. The area of Tarakan in particular, the Binalatung Street has improved quality, it aims to help the community activities to fulfill daily needs. In the activity of this beach road increase has risks that can affect the quality of the work so it is interesting to be researched from the point of view of Public Works and the planning of the city Department as the owner. The research method is done by spreading questionnaires and interviews, with respondents from the Public Works and the planning of the city Department of Tarakan as the owner of the project to increase the road of Tarakan. From the questionnaire will be processed with statistics to find out the highest risk events from the road enhancement activities. The results obtained from this study are from 13 risk variables from 9 risk criteria. analysis of inter-risk relationships followed by micmac analysis so that it is obtained: 1). Autonomous: 1 risk variable. 2). Dependent: 4 risk variables. 3). Linkage: 5 risk variables. 4). Independent: 3 risk variables.
Projection and Analysis of National Energy Consumption Levels on Indonesia’s Economic Growth Rate through Exponential Smoothing Approach
Authors: Dalimunthe D Y , Aldila H
Published: October 2019

This study briefly wants to know the value of the projections of Indonesia’s total energy consumption and how it affects the economic growth that occurs. This is also in line with the need for preventive actions related to the type of policy that will be carried out by decision makers where in this case the government will have an impact on the economic performance of a region reflected in the data presented in income posts and expenditure from Gross Domestic Product. The forecast method used in this study is the Exponential Smoothing method which emphasizes the procedure of continuous improvement of the latest observation objects. This method consists of three types, namely simple exponential smoothing, holt winters and triple exponential smoothing models which will be seen which model is the best. Based on the projection analysis, it was found that the Holt Winters Smoothing Smoothing method was the best method of the other method with R Square value of 0.608, RMSE of 68.446, MAPE of 4.495 and Normalized BIC of 8.888. Based on the projection results for the next n years, total energy consumption has an upward trend with the projection value in 2018 amounting to 1248.76 (thousand barrels of oil equivalent and experiencing an increase in 2019 amounting to 1273.47 (thousand BOE).
Preliminary Plant Design of Biofuel From Algae in Balikpapan, East Kalimantan
Authors: Harahap A F P , Ramadhan M Y A , Lestari T , Gozan M , Srinophakun P
Published: October 2019

Biodiesel is one of the promising alternative energy to replace fossil fuel which is produced from natural resources that contains lipid or oil. Common sources of biodiesel are lately growing controversy about the use of potential food sources for the production of fuel. One of the strongest non-food alternative for biodiesel source is algae since it can produce considerable amount of lipid based on their species and cultivation condition. One of the suitable species that can be used is Botryococcus braunii because of its ability to accumulate high amount of lipid and hydrocarbons extracellularly. All process simulations are done by using SuperPro Designer v9.0. The objective of this algae-based biodiesel preliminary plant design is to provide technological reviews, economical assessments, and HSE assessments of this plant. Based on supply consideration and process area needed, the best location for this plant is in Kariangau, Balikpapan, East Kalimantan with the estimated land area of 7,700 m2. The value of IRR and ROI of this plant is found to be 17.39% and 16.9% respectively. The NPV of this plant is 2,902,358.32 USD. It can be concluded from the profitability analysis that this algae-based biodiesel plant with capacity of 3,000 ton of biodiesel per year is economically feasible with payback period of 5.91 years.
Simulation of ejector for vacuum generation
Authors: Macia L , Castilla R , Gámez P J
Published: October 2019

Supersonic ejectors are used in a wide range of applications such as compression of refrigerants in cooling systems, pumping of volatile fluids, or vacuum generation. The objective of the present paper is to mesh and simulate, in an OpenFOAM environment with an open access implicit density-based solver HiSA, the physics of the vacuum ejector, and, later, compare the results with experimental measurements. In order to achieve this a 2D axisymmetric mesh made by hexahedral cells has been created. Steady solutions have been obtained, with prescribed total pressure in primary and secondary inlets. Secondary total pressure ranges from 1 to around 0.2 bar in which the secondary flow is zero. Numerical results are compared with experimental measurement, with two flowmeter sizes for small flow rate accuracy. Two regimes are encountered. In supercritic regime the secondary is chocked and sonic flow is reached in the second nozzle. In subcritic regime, the secondary flow is subsonic. The agreement is good, although simulation tends to slightly overestimate flow rate for large values region.
Effect of friction on nominal stress results in a single tooth bending fatigue test
Authors: Vukic M , Čular I , Mašović R , Vučković K
Published: October 2019

One of the main reasons for gear failure is bending fatigue, which occurs due to cyclic stresses at the tooth root region. Bending fatigue can cause crack initiation which, in turn, may propagate and result in catastrophic tooth breakage. Single tooth bending fatigue tests are frequently employed to generate statistically significant fatigue data at relatively low price. Hence, they are often employed as screening tests for bending fatigue behaviour of actual running gear pair. Since relatively small alteration of nominal tooth root stress values can produce significant change in bending fatigue lives, it is important to adequately consider the effect of friction and test fixture deformation when conducting single tooth bending fatigue tests. In this paper, numerical investigation of tooth flank friction effect on spur gear load capacity during single tooth bending fatigue test is carried out. Two different test fixtures are considered. Linear elastic finite element analysis is carried out to obtain nominal tooth root stresses. The results show that friction at gear tooth flank as well as fixture deformation can affect nominal tooth root stress results.
Gears or rotors - three approaches to design of working units of hydraulic machines
Authors: Stryczek J , Bednarczyk S , Codina E , Gamez-Montero P J , Ivanovic L , Matejic M
Published: October 2019

The gerotor pump has many advantages over other hydraulic pumps, such as high reliability, compactness, lower noise in running conditions etc. Considering the increasingly stringent regulations in the field of environmental protection, one of the main goals in the industrial applications of gerotors is to improve their design by using light materials and optimize their performance. This paper will give an overview of modern research that focuses on improving the performance of gerotor pumps. A joint publication of three university centers, namely of Wroclaw, Terrassa and Kragujevac, presents their original approaches to the problem of designing gerotor and orbital systems. The presentations have been prepared in separate parts, but according to similar rules. The first part of the paper focuses on meshing between internal and external gear of gerotor. Analysis for both cases, moved axis and fixed axis, will be provided in accordance to their working characteristics and their application. The second part of the paper provides the design of a gerotor pump strikes a balance between volumetric efficiency, manufacturability and mechanical efficiency. The third part of the paper defines the methodology for selecting the best combination of geometric form parameters of the trochoidal gearing in relation to the reduction of contact stresses and improving other characteristics of the pump. All three parts provide manufacturing and application review in the fluid power machines. Paper concludes with presented theoretical and experimental review of the authors and their practice achievements.
Stress analysis of lifting table using finite element method
Authors: Rasovic N , Vučina A , Obad M
Published: October 2019

Lifting table has been designed and developed through the concept of Learning Factory (LF) at the University of Mostar. The idea for lifting table design has come from the local industry needs for a lifting platform that should lift a man and/or load at a certain height. For safety reasons, design is checked under the loading using a method of finite element analysis. The paper predicts and explains methodology for structural analysis used in presented case study. Results of FEM analysis are basis for making ways and guidelines to optimize current design in order to get optimal parameters for weight, stability, capacity, mobility and layout of the lifting table.
The response of a random vibrations of nonlinear structure under white-noise excitations
Authors: Stan P , Stan M
Published: October 2019

Random vibration is the phenomenon wherein random excitation applied to a mechanical induces random response. Random vibration is the most practical of the areas discussed in this paper. In this paper, the sistem is excited by a force W which is a random process described. A method is to replace the governing set of non-linear defferential equations by an equivalent set of linear equations the defference betwen the sets being minimized in somme appropiate sense. In this way, the parameters of the linearised system are determined.
Analysis of the wind effect on the mechanical structures in the case of the four-side sunshade
Authors: Markovic B , Krajišnik M , Đurić A
Published: October 2019

This paper presents the analysis of the wind effect of four-side sunshade construction. The aim of the paper is to demonstrate the possibility of applying analogy in research, with examples from civil constructions, in order to simplify and reduce the analysis. The paper presents the analytical calculation of the pressure on the sides of the four-sided sunshade, analogously to the calculation of pressure on the four-sided roofs of civil construction objects.
Failure diagnosis and prognosis of sliding bearings
Authors: Antunovic R , Vučetić N , Halep A
Published: October 2019

Sliding bearings are widely used machine elements from which the correct operation depends on the availability of many technical systems and great attention is paid to the study of the prediction method for sliding bearings. Problems that occur with sliding bearings lead to high levels of vibration and noise. One of the important parameters in the diagnosis and prediction of the failure of sliding bearings is the thermal analysis. In addition to these parameters, frequent vibration spectrum analysis, oil film thickness and other relevant parameters are often used. Using advanced technologies, it is possible to significantly reduce the duration of measurement, and on the other hand increase the accuracy of diagnostic methods. Phase logic is a mathematically formalized mode of representation modeling uncertainty. In this paper, a selection of damage in the operation of a sliding bearing has been made and the way of diagnosing these problems is shown. Methods that integrate several diagnostic parameters into one show reliable methods of early detection of slip bearing damage.
Application of the multi-criteria decision making in the selection of materials of composite shaft
Authors: Djordjevic Z , Jovanovic S , Kostic S , Blagojevic M , Nikolic D
Published: October 2019

Thanks to the outstanding combination of construction and special features such as high resistance and stiffness, increased wear resistance to fatigue, higher values of critical speeds, lower mass, long lifetime, and so on, today a growing number of shafts, especially in the automotive industry, are made of composite materials. The optimal values of these parameters can be obtained by selecting the appropriate material.

The selection of materials in the process of product design requires efficient decision-making. Incorporating hybrid materials, in addition to providing the potential for improved performance, can make the decision-making process in the selection of material difficult. In this sense, the use of multi-criteria decision making (MCDM) was used as an adequate tool and support for making optimum decisions. This method has the potential to improve practically all areas of decision making in engineering from design to product.
Tools of organizational-economic mechanism of internal control functioning
Authors: Aristarchova M K , Fakhrutdinov V S
Published: October 2019

The article touches upon the topical issues of the internal control functioning at the enterprise. The tools developed by the organizational-economic mechanism of functioning of internal control, including the principles, functions, logicaly, time aspect, controlling, norms. The structural and functional components of internal control are identified, the technology of each of them is considered. The adaptive organizational structure of the risk management and internal control system is formed, which can be the basis for the formation of the model of internal control of the gas transportation enterprise.
Modeling of 3D temperature field in butt welded joint of 6060 alloy sheets using the ANSYS program
Authors: Matuszewski M
Published: October 2019

In work, the modeling of a three-dimensional temperature field in a butt weld connection of two 6060 aluminum alloy sheets using Finite Element Method is presented. The calculations were performed for two welding methods: TIG (Tungsten Inert Gas) and MIG (Metal Inert Gas). The Goldak's double ellipsoidal heat source model has been used in modeling. The thermal-mechanical properties of the material were assumed to depend on the temperature. The Workbench, DesignModeler, Mechanical, Fluent and CFD-Post modules of the ANSYS program were used for numerical simulations. In the description of the geometry of joints, cube type elements were used, with density of grid in the heat affected zone. The parabolic shapes of face and root were assumed based on the literature and results of the experiment. The temperature distributions in cross-sections of welded joints as well as welding thermal cycles at selected points were analyzed. The results of numerical simulations were verified experimentally. Comparison of calculated and obtained in the experiment the characteristic limits of heat affected zones showed satisfactory compatibility. The directions of heat propagation determined by vectors of cooling rates coincide with the longitudinal axis of dendritic grains determined on the basis of metallographic tests.
Energy performance of the Serbian and Estonian family house with a selective absorption facade
Authors: Lukic N , Nešović A , Nikolić N , Siirde A , Volkova A , Latosov E
Published: October 2019

In this paper the influence of selective absorption facade on heating energy consumption of the family house is analyzed. Two houses built according to Serbian and Estonian building energy performance regulation (minimum requirements) are simulated by EnergyPlus software. For simulation process the appropriate weather data are used (Serbia – Kragujevac and Estonia – Tallinn). Heat transfer by radiation, gains and losses can be a significant part of the energy consumption, during heating season. Using selective absorption facade those gains and losses could be increased and reduced, respectively. Several simulation scenarios of Serbian and Estonian house are carried out. Different weather conditions in case of the defined houses point on specific impact of the applied improvement on family house energy performance. Maximum annual percentage savings of heating energy compared to house without selective facade, in case of Serbian house are obtained as 8.32%. In case of Estonian house maximum savings are obtained as 1.92%.
Innovative solution of fine horizontal trash rack for small hydroelectric power stations
Authors: Miltenovic A , Prodanović M , Beju L , Miltenović V , Velimirović N
Published: October 2019

Alternative energy sources have a number of advantages over energy derived from fossil and nuclear power plants. In this way, the environment is protected, and many countries are encouraging the use of alternative energy sources. Large potential from this aspect has small hydropower plants, which are not expensive, they can be installed on small rivers, and in this way the received electricity is much cheaper. One of the problems that need to be solved is to prevent the penetration of impurities into turbine plants. This is solved by placing protective trash rack on water intakes. The paper presents an innovative solution for horizontal fine trash-rack with cleaning function for small hydro-electric power stations.
Insulation impact on appliance acoustic characteristics
Authors: Zvolensky P , Lestinsky L , Dungel J , Grencik J
Published: October 2019

The paper is aimed on types of insulation actually used in washing machines and raising requirements on its characteristics. Next part is design of unconventional insulations, which will be applied directly on appliance. Then, series of tests will pass (according to regulations), so it will be possible to determine acoustic power. After that, we will use simulation to determine impact of insulation rigidity on washing machine shell (with identification of acoustic benefit). Relatively important factor is rigidity of washing machine shell and forces affecting the shell. Force affecting on the shell depends on inner and outer tub weight (and all equipment attached), load, unbalance in a drum and revolutions during spin cycle. Usually more rigid washing machine shell produces less noise than weaker shell. That’s why is relatively important to stiffen shell. Doing this by changing type of insulation is advantageous because it is possible to do without any significant side effects.
Indoor positioning and navigation system for autonomous vehicles based on RFID technology
Authors: Regus M , Talar R , Labudzki R
Published: October 2019

The localization and navigation systems play a very significant role in today’s world. They are commonly used in different fields of industry as well as in our daily life. Location of objects is crucial in logistics and transport to provide the real-time monitoring and management of process chain. There are numerous methods which allows to follow people and objects within defined area. One of them is Global Positioning System (GPS), which provides geolocation of objects on the earth as long as an unobstructed line of sight to four or more satellites is assured. As a consequence of this limitation, GPS cannot be applied for indoor environments. Recently, a couple of Indoor Positioning Systems (IPS) based on different technologies have been developed. Despite the drawbacks and limitations, these systems have been successfully applied for different fields of industry. Notwithstanding the above, reliable, accurate, cost-effective and simple indoor positioning methods are still in the area of scientists interest. Present paper provides a general overview of existing indoor positioning systems as well as authors concept of 2D wireless indoor positioning and navigation system dedicated for autonomous vehicles based on Radio Frequency Identification (RFID) technology.