bluuebunny/crossref_metadata_2025 huggingface dataset:
Landslide Inventory and Disaster Management Based on Community Participation for Sustainability Environment in the Volcanic Area
Authors: Masruroh Heni , Sumarmi  , Bachri Syamsul , Putra Alfyananda Kurnia , Andhika Yudha P
Published: December 2023

Landslides are still an essential problem for areas with rough morphology. There are several ways to map landslide vulnerability that can be used to reduce disaster risk. To produce maps with high accuracy is one of the challenges. This study proposes a community-based landslide inventory mapping approach. Communities are important in providing information about disaster events and are essential to disaster management. The aims of this study are 1) to conduct field investigations for the community for landslide inventory; 2) to identify and analyze the role of the community in disaster risk reduction for a sustainable environment. The method used in this research is using participatory mapping (P-GIS) and focus group discussion. The community is participatively asked to reconstruct past landslides. Community-based landslide data inventory using geospatial technology in the form of remote sensing imagery as support. The results of community participation showed that there were 138 landslides with translational and rotational landslide typologies. There is a community role in reducing the risk of landslides through the Taji Village Disaster Preparedness Community (SIBAT). The management model for land management carried out by the community is based on the principles of environmental sustainability in the form of easy application, local-based materials, local-based culture, and local-based knowledge, and provides sufficient economic income.
Flood Affected Building Footprints 3D Model from LiDAR and Aerial Photogrammetry (Case Study: Pandugo Street, Surabaya)
Authors: Hapriansyah Sultan Alifian , Handayani Hepi Hapsari , Maulana Mahendra Andiek
Published: December 2023

Frequent rainfall events in Surabaya occurred due to tall silt within the channel, which prevent water flow and at that point flooding onto the street. Information about the events, including the simulation and prediction are needing accurate visualization to be major consideration for infrastructure and public facilities decision-making. 3D modelling are accurate enough as flood disaster risk management for buildings, using LiDAR and aerial photogrammetry that can provide strong visual representations accurately. DSM and DTM derived from aerial photogrammetry survey are then used to get DSM LiDAR. DSM&DTM from LiDAR was taken in 2016 and DSM&DTM from aerial photogrammetry was taken in 2022. The only objects that are updated are buildings from DSM aerial photogrammetry then applied to DSM LiDAR. Buildings footprint, road network, nDSM, and flood inundation data are then processed to get the 3D Model of buildings and floods. The model are then evaluated by comparing the total of affected buildings with manual methods. Validation on buildings height also performed and results in 0.86233 RMSe that achieved the LOD2 standard. Potential further studies could focus on improving the LOD and considering other parameters such as rainfall data or gutter data.
3D Building Visualization Using LOD1 Level Lidar and Orthophoto Data (Case Study: Jalan Tambak Mayor Surabaya)
Authors: Putri Klarissa Ardilia , Maulana Mahendra Andiek
Published: December 2023

Surabaya is the second largest city in Indonesia after Jakarta, with a population of more than 2.8 million people. As the second largest city after Jakarta, of course Surabaya is classified as a city with a high population and building density. With this high level of building density, it is necessary to carry out good regional planning. Good regional planning is an important tool in creating cities and regions that are sustainable, environmentally friendly and provide a high quality of life for their residents. It also helps in addressing complex urban challenges and ensuring wise use of resources. Currently, various methods and technologies have developed that make it easier for the government to carry out regional planning. One method that can be used is to carry out 3D city modeling. Three-dimensional (3D) modeling is a technique used to create a digital model of an object or environment in three dimensions, using computer software capable of producing 3D images based on the data provided. Three-dimensional modeling for buildings with LOD1 level utilizes data obtained from field surveys, remote sensing and numerical modeling. Through this research, 3D city modeling was carried out using LiDAR data and aerial photography to analyze the condition of buildings in the Jalan Tambak Mayor area. This approach uses a 3D city model as the basis for analysis using ArcGISPro software. In this research, data updating will be conducted, which involves directly capturing aerial photographs in the field, as the existing aerial photograph data is from 2016 and needs to be renewed. Based on the resulting modeling, the results of 3-dimensional building modeling are shown on a map which is classified into 5 classes with a building height range between 0 - 46 meters.
Analysis Of 3-D Building Modeling Using Photogrammetric Software: Agisoft Metashape And Micmac
Authors: Rahman A.D.M , Cahyono A.B
Published: December 2023

In constructing three-dimensional models, photogrammetry techniques, particularly close-range photogrammetry techniques, are growing and becoming an alternative, specifically for architectural and historical site modeling. Because they are less costly, simpler, and quicker to complete while producing positive results, there is a great number of photogrammetry software. Still, it is difficult to determine which application provides the best measurement results because user expectations vary. It is necessary to conduct geometric precision and visualization analyses to assess the software’s output. For this experiment, 3D models of a building were created using Agisoft Metashape and MicMac. The geometric accuracy calculated by Agisoft Metashape has RMSE values of x=0.025 m, y=0.037 m, and z=0.021 m. RMSE values for the MicMac are x=0.066 m, y=0.129 m, and z=0.118 m. Visually, the Agisoft Metashape-created three-dimensional model offers superior visual results and fewer connection points than the MicMac GUI. On a three-dimensional building model processed with Agisoft Metashape, the generated cloud-to-cloud distance is comparable to the distance between the reference point cloud. Except for the building’s rear, the distance between clouds using the MicMac is nearly identical to that of the reference point cloud.
Geological Structure Model for Recharge Area in Patuha Geothermal Field
Authors: Indriani Rista Fitri , Anjasmara Ira Mutiara , Utama Widya , Dzulfiqar Rafi Muhammad Erfand , Lumban Gaol Daniel Juliadro
Published: December 2023

Geothermal sustainability requires geological structure analysis using gravity methods for groundwater management. Geological structure analysis reviews fault data. Geological structure as a pathway for fluid movement for groundwater management in the research area, especially the Patuha Geothermal Field, West Java. This study uses global gravity model, terrestrial gravity, DEM, and geological data. The gravity method applied in this research involves calculations for latitude correction, free air correction, bouguer correction and terrain correction. The final results of this research are free air anomaly, complete Bouguer anomaly, and model evaluation (MRSE, MRE, and MAE). Free air anomaly results from free air correction of global gravity model data. DEM topography analyzes free air anomaly. The FAA data model evaluated RMSE at 1.27, MRE at 0.004, and MAE at 0.83. 138.02–280.26 mgal is the FAA range. The research area’s elevation range is 836–2431 m. Topography and free air anomaly correlate 0.75. Positive high connection. Mountains and plateaus may have positive gravity anomalies. Free air, bouguer, terrain, and CBA are applied to global gravity model data. The CBA model evaluation indicates quality. RMSE is 1.47, MRE is 0.012, and MAE is 1.11. CBA fluctuation implies fault spread. Faults serve as water flow conduits and channels, increasing the risk of infiltration. Meanwhile, cracks are being distributed as conduits and for infiltration. This research forms the basis for developing and increasing geothermal production so that further studies are needed regarding the influence of geological structures for reservoir in geothermal areas.
Deep Neural Network to Classify Seabed Sediment Using MBES Multifrequency
Authors: Khomsin  , Hadicahyo O
Published: December 2023

This study investigates the classification of sediment distribution and types in inland waters using Artificial Neural Network (ANN) models based on multibeam echosounder data. Multibeam Echosounder Technology (MBES) is an acoustic instrument that emits high-speed sound pulses to map the bottom of water bodies. Valuable information about sediment characteristics can be obtained by analyzing the backscattering phenomenon, which measures the acoustic intensity reflected from the water bottom. The angular response curve (ARC) method, developed by Fonseca and Calder, is employed to analyze the relationship between backscatter intensity and the angle of reflection. The ANN models in this study are trained and tested using intensity values and angular response curves obtained from multibeam echo sounders. The ANN model architecture consists of an input layer, three hidden layers, and an output layer. The sigmoid activation function is utilized in the output layer, while the ReLU activation function is applied to the input and hidden layers. Performance evaluation demonstrates that the ANN model using uncorrected data achieves remarkable accuracy, with 100% accuracy obtained in both the training and testing stages. The model exhibits a training loss value of 0.059443 and a testing loss value of 0.110030, indicating its effectiveness in capturing patterns and reducing errors. Visualizing the sediment distribution in Waduk Selorejo reveals a relatively balanced presence of Clavey sand and Sandy silt sediment types. However, noticeable differences arise between the corrected and uncorrected data, which can be attributed to the alterations made during the data correction process. The best-performing ANN model achieves a testing accuracy of 0.75, indicating that it does not perfectly predict the given data. Acknowledging the potential for prediction errors when using corrected data is important.
Construction Design of the Floater Considering the Free-Falling Impact of the Floatplane on Calm Water
Authors: Alifia Windha Umi , Sulisetyono Aries
Published: December 2023

The floatplane-type aircraft is very suitable to be developed as a means of transportation connecting the scattered islands in Indonesia, as it has floats under the fuselage to make landings and operate on the water surface. In bad weather, a floatplane can lose lift, resulting in a free fall from an abnormal height and a violent collision between the floatplane structure and the water surface. Meanwhile, regulations require that the strength of the structure be able to withstand the impact load due to an emergency landing. This paper proposes a floater construction design for the N219 floatplane with three scantling variations of 5083 H321 aluminium material that considers the total payload and take-off weight. The magnitude of the impact load on the bottom of the float with the water surface in the case of free fall at 0.5 m and 1 m height is predicted by the Wegner equation model at each cross section along the float. The magnitude of stress in each floater construction design is evaluated by the principle of the finite element method using commercial software. The simulation results show that all models have a maximum stress less than permissible stress and also maximum deformation is unsignificant.
Determination of Boundaries of Regional Marine Management Area in Central Sulawesi Province against Surrounding Provinces
Authors: Pribadi Cherie Bhekti , Hariyanto Teguh , Maulidi Fauzul
Published: December 2023

Determining the boundaries of marine management areas is very important for an area to obtain the authority in order to manage natural resources in its territorial sea as regulated in the law on regional government for exploration, exploitation, and management of marine resources. The legal basis for determining the boundaries of marine management areas is regulated in Law Number 23 of 2014 concerning Regional Government and Minister of Home Affairs Regulation Number 141 of 2017 concerning Regional Boundary Affirmations. The two legal bases are sufficient to be used as a reference in determining the boundaries of marine management for the Province of Central Sulawesi and the boundaries for the division of regional marine space for each district and city. Central Sulawesi Province has many islands around there and most of the districts and cities are coastal areas, it is deemed necessary to determine the boundaries of marine management and the division of district/municipal marine space. The method used is the baseline method, which is using the normal baseline. Based on the results obtained, the area of marine management in Central Sulawesi Province is 73,519.507 km2. For making the median line, namely between the Provinces of Central Sulawesi and North Maluku because there is an overlapping area of 1,218.042 km2. In the results obtained in the division of regency/municipal sea space, the total area is 3,3592.222 km2.The largest marine spatial distribution area is in Banggai Laut Regency with an area of 5,913.362 km2 and the smallest is Palu City at 102.024 km2.
Enhancing Sustainability and Resilience in Surabaya Coastal Residence Through Advance High Water Level Modelling
Authors: Hariyanto Irena Hana , Gede Bhadra Pranaya Sardjitha I
Published: December 2023

Coastal areas are increasingly vulnerable to the impacts of climate change particularly the sustainability and resilience of the coastal residences. Surabaya as a coastal city in Indonesia is not an exception in facing the significant challenges. By developing an advanced high water modelling, it could predict the impacts of high-water levels on coastal residences. The spatial and temporal patterns of flooding events are analysed, allowing for the identification of vulnerable areas. This study shows the coastal residence in Surabaya City and their potential to be affected by tidal flooding based on the high resolution satellite imagery and actual Global Navigation Satellite System (GNSS) measurements. The result shows that an area with no barrier to separate the residential area with the sea has a bigger chance to be affected by tidal flooding. In this research, the study locations are divided into northern, middle, and southern locations. It shows that the southern location is the most vulnerable residence with possibility water intrusive as far as 10 meters far from High Water Level (HWL) reference. With an accurate position of the HWL coastline, the development of settlements and coastal areas is expected to be better and safer, especially from the tidal floods.
Investigation of the process of extraction of copper from dust of electric filters of oxygen-flare smelting furnace with sulfuric, thermal, and extractive phosphoric acid
Authors: Ramazonova Dilbar , Turayev Zokirjon , Mamurov Bakhodir , Shamishova Aisholpan , Absattorov Diyorbek , Makhmayorov Jasur , Usmanov Ilkham , Samadiy Murodjon
Published: December 2023

The results of studies on the extraction of copper from the dust of electrostatic precipitators of oxygen-torch melting with solutions of sulfuric, thermal, extraction phosphoric depending on S:L, concentration and duration of the leaching process are presented. It has been established that the maximum degree of copper extraction is observed when using extractive phosphoric acid, which reaches more than 86%. The optimal parameters for the extraction of copper in extraction phosphoric acid are S:L = 1:10, temperature 90°C and mixing time 25-30 minutes.
Development of low cost pyranometer IoT based solar irradiance measurement station
Authors: Lim Matthew T M , Tan Rodney H G , Tan G A , Hew C H , Lee W K , Mercha Mohammed
Published: December 2023

This paper presents the design of self-sustainable IoT pyranometer station using low cost BPW34 photodiode. The sustainable power of the station is achieved by a 20W solar panel charges a 7.2Ah lead acid battery through a charge controller. This station uses low cost BPW34 sensors which are connected to a 16-bit ADC module to convert the analog voltage into digital data. This module is connected to an ESP32 microcontroller that connects to Wi-Fi and sends sensor readings to ThingSpeak IoT platform to allow monitoring. This study collected over 36000 data points throughout February 2023 with an average daily data loss of 2.47%. Polynomial regression method was used to determine a best fit curve equation between the BPW34 sensor and the reference sensor. The result shows that the proposed BPW34 sensor achieve the highest error of ±80W/m2 with approximate 3% of daily data. The summary, a second order polynomial equation is found best fit for the proposed low cost BPW34 sensor.
Experimental investigation on photovoltaic thermal system performance with different attachment techniques
Authors: Umam Mukhamad Faeshol , Hasanuzzaman Md , Rahim Nasrudin Abd
Published: December 2023

Photovoltaic thermal (PVT) systems promise a more optimal solar energy utilization by producing electricity and heat simultaneously. However, the thermal collector design and the way it is connected to the PV panels are still a problem for the PVT system. This study aims to answer the use of thermal paste and insulation in thermal collectors are some of the issues in PVT system manufacturing. An experimental study was conducted by making three scenarios of thermal collectors combined with PV panels and then tested in an indoor solar simulator. Each design was tested with five different cooling water flow rates. This study found that thermal paste and insulation can improve the electrical power of PVT systems by up to 17.59% and its thermal performance increase by 10.13%. Thus, the use of thermal paste and insulation should be done in the manufacturing of each thermal collector for PVT systems.
Energy Management Strategies of Solar Rooftop Campus with Battery Energy Storage System (BESS) And EV Supply Equipment (EVSE) using HOMER
Authors: Mazlan M A A , Dahlan N Y
Published: December 2023

Commercial sector has been among the largest source of electrical load demand in Malaysia including educational buildings. Nowadays, distributed energy resources, such as solar photovoltaics (PV) and battery energy storage systems (BESS), are being implemented in educational campus to save and manage its energy consumption. Additionally, electric vehicles (EV) are becoming more popular as they are more environmentally friendly than the traditional gasoline-powered cars. This research aims to examine the cost-effectiveness, environmental and technical aspects of a microgrid system that includes grid-connected solar panels, BESS and EV supply equipment (EVSE). The study was conducted for Universiti Teknologi MARA campus Pulau Pinang. The campus microgrid models are simulated using HOMER software to explore four different of microgrid configurations. The load profiles of the buildings in the campus were gathered and used in the model to identify the optimum microgrid model. The findings show Grid-PV-BESS has the best hybrid energy system based on the weightage sum decision making approach considering multiple criteria assessments. Through this study, a sustainable hybrid energy system in the educational campus can be proposed integrating solar PV, BESS and EVs.
Solution-processed lead-free cesium titanium halide perovskites and their structural and optical characteristics
Authors: Aslam Sameen , Mohamad Samsuri Siti Azrah
Published: December 2023

Two primary challenges impede the extensive utilization of organic-inorganic lead halide perovskites: instability and potential risk of lead contamination. This paper describes an easy and effective solution-phase method for synthesizing lead-free Cs2TiI6 perovskites using inverse temperature crystallization. The perovskite precursor was deposited on glass substrates using various methods. The Cs2TiI6 films exhibit a cubic structure with a lattice parameter of 11.57 Å. The drop-cast thin film exhibited strong and broad absorption in the visible spectrum, indicating that Cs2TiI6 possesses notable optical properties. The optical energy gap calculated for both direct and indirect is 1.68 eV and 1.65 eV, respectively). The refractive index and optical conductivity demonstrate that Cs2TiI6 is an excellent optical absorber for photodevices. This study offers valuable perspectives for the advancement of lead-free double perovskites.
Modeling and analysis of rooftop solar photovoltaic system for educational institution in Malaysia
Authors: Mohd Zublie Muhammad Firdaus , Hasanuzzaman Md. , Rahim Nasrudin Abd
Published: December 2023

The education sector is one of the contributors to greenhouse gas emissions. Therefore, the education sector strongly supports the government’s aspirations to reduce carbon emissions. Energy consumption is related to the amount of carbon emission production—energy consumption information helps to forecast energy savings while creating carbon emission reduction. The research aims to propose a new modeling of rooftop solar photovoltaic (PV) by installing the Net Energy Metering (NEM) meter in the Politeknik Sultan Azlan Shah (PSAS) educational institution's ring distribution system. The energy demand at PSAS in 2022 is 3,916,534 kWh/year, equivalent to an energy cost of RM 1,429,535. The new model design is based on setting 20% of the total power supply in PSAS generated by solar. A feasibility analysis on the proposed modification of the distribution layout design found that in the next four years, it is predicted that the minimum energy savings that PSAS will obtain are 2,075,763 kWh, while the annual bill savings are RM 757,654. This energy saving leads to a reduction in gas emissions where PSAS can reduce the production of 1,526,620 kg of CO2 to the environment while saving 38,165 mature trees from being cut down.
A review on blue and green hydrogen production process and their life cycle assessments
Authors: Hamed Ali Mahmoud , Tuan Kamaruddin Tengku Nordayana Akma , Ramli Nabilah , Abdul Wahab Mohd Firdaus
Published: December 2023

Green and blue hydrogen are two types of hydrogen generated from renewable energy sources and fossil fuels, respectively. Green hydrogen is created by splitting water molecules into oxygen and hydrogen using renewable energy sources such as wind, solar or nuclear power in a process known as electrolysis. Blue hydrogen, on the other hand, is produced by reforming natural gas and capturing and storing the resulting carbon emissions. The production of both green and blue hydrogen has implications for the environment, and a life cycle assessment (LCA) can be used to evaluate the environmental impacts of hydrogen production and use. An LCA considers the entire life cycle of a product, from raw material extraction to end-of-life disposal and assesses the potential environmental impacts at each stage. The LCA of green hydrogen production generally shows a lower environmental impact compared to blue hydrogen production. This is because green hydrogen production does not emit any carbon emissions during the process, whereas blue hydrogen production still results in the emission of carbon dioxide. However, the environmental impact of green hydrogen production can vary depending on the source of the renewable energy used for electrolysis.
Luminescence properties of Eu3+ doped Li2SrSiO4 phosphor
Authors: Bhure P P , Puppalwar S P , Tingane K T , Sahu K V , Suryawanshi S M , Bahirwar B M
Published: December 2023

The modified solid-state reaction method has been used in this work to prepare Eu3+ doped Li2SrSiO4. PL spectroscopy was used to investigate photoluminescence (PL) properties of the sample. X-ray powder diffraction study was used to confirm the crystalline nature and phase purity of the sample. The particle size of prepared material ranges from 37 to 56 nm was observed from XRD. From PLE and PL spectrum the excitation and emission spectra of photoluminescence for Eu3+ doped Li2SrSiO4 were recorded. The prepared Eu3+ doped Li2SrSiO4 phosphor might have application in solid state lighting.
Structural and magnetic investigation on Cr3+ substituted Mn0.25Cu0.25Zn0.5Fe2O4 nano ferrites by co-precipitation route
Authors: Balbudhe Bhaurao R. , Badwaik Dilip S. , Wandhare Rupesh S. , Sharma Ajay , Daf Sarang R. , Suryawanshi Shrikant M.
Published: December 2023

A low-temperature co-precipitation approach was used to prepare Mn0.25Cu0.25Zn0.5Fe2-xCrxO4 (x=0.0, 0.4). The X-ray diffraction with most intense (311) peak and crystallite size in the range 25-29 nm confirms the formation of spinel nano ferrites. The transmittance within 400-600 cm-1 for all samples confirms Fe-O bond at tetrahedral and octahedral sites of prepared spinel nano ferrites demonstrated by FTIR. The soft magnetic nature of prepared material was recorded by VSM. The small Coercivity (16.6032 &20.9224 Oe), retentivity (1.4588 &1.5617 emu/g) and magnetic saturation (23.83 &31.8169 emu/g) demonstrates superparamagnetic, pseudo single domain and randomly oriented multi-domain nature of the nano ferrites. The produced superparamagnetic nano ferrites advantageous in high frequency and biomedical applications.
pH influenced synthesis and characterization of Ni0.3Cu0.3Zn0.4 Fe2O4 nano ferrite for energy storage and high frequency applications
Authors: Suryawanshi Shrikant M. , Badwaik Dilip S. , Hedaoo Pushpalata S. , Warhate Vijay V. , Badwaik Vandana D. , Lekurwade Pranali P.
Published: December 2023

A spinel nanocrystalline Ni0.3Cu0.3Zn0.4 Fe2O4 was prepared using co-precipitation method maintaining pH -7,10 and 12. The pH influenced structural, spectroscopic and magnetic parameters were recorded by X-ray diffraction (XRD), FTIR and VSM. The crystallite size (31.12 nm to 45.32nm), lattice dimension (8.4175 Å to 8.4368 Å), strain (2.525x10-3 to 3.669x10-3), dislocation density (1.024 x10151/m2 to 4.867 x10151/m2) shows considerable structural enhancement due to pH variation. The Fe-O group analysis by FTIR within 400-600 cm-1 corresponds to tetrahedral (587 cm-1 to 591cm-1) and octahedral (442 cm-1 to 444 cm-1) vibration confirms the formation of spinel nanoferrites. The smooth hysteresis M-H loop with coercivity (12.5826 Oe to 11.2212 Oe), magnetic saturation (62.8431 emu/g to 66.2495 emu/g) and retentivity (0.6375 emu/g to 0.6988 emu/g) describes multi domain nature of prepared material. The obtained structural and magnetic parameter clearly indicates energy storage and high frequency application.
Actual and design wind loads for overhead transmission lines in the Central European part of Russia
Authors: Loktionov O A , Fedotova E V , Kondrateva O E , Dolchinkov N T , Kuznetsov N S
Published: December 2023

This paper reveals an impact of the climatic loads on the sustainable operation of power grid facilities. An overview is provided considering various international standards related to the design of overhead transmission lines. The aim of the research was to analyze and compare the actual and design values of wind loads for transmission lines located in the Central European part of Russia and operated by the power grid company “Rosseti Center and Volga Region”. An analysis of wind load dynamics has been carried out considering the territory of 9 subjects of Russia and 1983-2022 timeframe. The actual climate data were computed according to the direct measurements of the weather stations. Nomograms of the maximum annual wind speeds are formed utilizing the first limiting Gumbel distribution for two climatic regions of the research area. The retrospective wind loads values were compared against the design values. The results of the study show that climate standards should be updated more frequently as it is the case nowadays, in particular, it relates to revision of existing wind loads or recalculation of wind speed correction factors for the near future.
Design of 6 slots/10 poles modular rotor sandwich switched flux switching permanent magnet motor
Authors: Soomro Irfan Ali , Sulaiman Erwan Bin , Jenal Mahyuzie Bin , Zarafi Bin Ahmad MD , Binti Mostaman Nur Afiqah
Published: December 2023

Conventional flux-switching permanent magnet brushless machines (PMFSM) gained a lot of attraction due to their high torque densities, simple and robust rotor structure, and the permanent magnets and coils on the stator. The sandwich PMFSM machine has been proposed to improve the torque density of the machine in which two PM pieces are sandwiched in one stator pole to enhance the PMs usage efficiency. 2D finite element analysis (2DFEA) method is employed to compare the performance of sandwich PMFSM with salient rotor topology with that of sandwich PMFSM with modular rotor, in terms of flux linkage, flux distribution, flux strengthening, induced back EMF, cogging torque and average torque. From the results it is shown that the salient sandwich PMFSM and sandwich PMFSM modular rotor produces 9.28Nm and 6.7Nm, respectively.
Daylight performance of horizontal light pipe and shading systems in office room with bilateral opening
Authors: Elsiana F , Ekasiwi SNN , Antaryama IGN
Published: December 2023

Daylighting implementation in the building can reduce building energy use. Previous research about Horizontal Light Pipe and shading systems in the Tropics examined daylighting strategies in a room with a unilateral opening, which receives daylight through a window in one wall. The bilateral openings from two adjacent side windows have the potential to improve daylight distribution and have yet to be discussed in previous research. This research evaluates the daylight level and distribution of HLP and shading systems in a room with a bilateral opening from two adjacent windows. The research method is experimental with simulation using IES-VE (Integrated Environment Solution-Virtual Environment) as a tool. The Daylight Factor (DF) and Uniformity Daylight Factor (UDF) of a room with bilateral openings from two adjacent windows were compared with a room with bilateral openings, HLP, and shading systems. The results indicate that integrating HLP and shading systems in an office room with two adjacent side windows decreases the average Daylight Factor (DF) by 48.74%, bringing the average DF fulfilling the recommended DF level for the office room. HLP and shading systems improve the Uniformity Daylight Factor and percentage of sensor points with DF 2-5%, as high as 56% and 67.38%, sequentially.
Experimental investigation of nucleate pool boiling heat transfer characteristics on modified copper surface via laser-structured microstructures
Authors: Sugumaran L , Zubir M N M , Newaz K M S , Zahari T Z T , Aznam S M , Halil A M
Published: December 2023

This study aims to evaluate the performance of pool boiling heat transfer on a structured surface subjected to constant heat flux. A nanosecond laser ablation was used to create different surface profiles on copper samples. Specifically, a series of step-like microstructured surfaces with varying secondary groove widths were fabricated to investigate their effect on pool boiling heat transfer performance of distilled water. The results indicated a significant enhancement in heat transfer performance for the laser-structured surfaces compared to the smooth surface at low heat flux. This improvement was attributed to the increased surface area, nucleation frequency, and nucleation site density. However, at higher heat flux, the surface with a smaller secondary groove width (LS 2) exhibited a decline in heat transfer performance, which was likely due to larger bubble escaping resistance. In contrast, the surface with a larger secondary groove width (LS 1) demonstrated the best heat transfer performance. The current work would help in finding an optimum surface structuring design for gaining higher boiling heat transfer performance which benefits industries dealing with thermal management processes.
A real-time thermal behaviour monitoring and analysis of a 500 kWh grid-connected battery energy storage system
Authors: Shahroom Afif Firdaus , Mansor Muhammad , Ying Yong Jia , Abd. Rahman Muhamad Safwan
Published: December 2023

Statistical analysis yields critical data for risk evaluation and management of a stationary battery energy storage system (BESS). Lithium-ion (Li-ion) batteries have attained huge attention for both stationary and non-stationary applications due to their lucrative features such as lightweight, high energy density efficiency, and long lifespan. However, detailed analysis and trends subjected to thermal behaviour of the device especially in grid-connected BESS application is still neglected. Therefore, this paper presents a statistical analysis for thermal behaviour of a grid connected BESS. The significance of Li-ion battery employing battery thermal management is presented, which can guarantee a reliable and safe operation as well as examining the effect of voltage, current and state of charge (SOC) on BESS operation. The large group of datasets recorded daily with five-minute intervals are difficult to be analysed numerically in a timely manner. Thus, the analysis can be made by visualizing the numerical data that was retrieved through representational state transfer (REST API) for easier interpretation and trend analysis. The visualization is made using Microsoft Power BI and presented in this paper.
Thermal performance of serpentine channel immersion cooling for lithium-ion battery 18650 with HFE-7100
Authors: Febriyanto R , Pranoto I , Ariyadi H M , Khasani
Published: December 2023

This paper presents Serpentine Channel Immersion Cooling (SCIC) as a new design for battery immersion cooling applications using HFE-7100 dielectric fluid. The main objective of this research is to analyze the temperature generation characteristics of Li-ion batteries with the performance of natural convection (NC) and Serpentine Channel Immersion Cooling (SCIC) with HFE-7100 liquid. The depth of discharge (DoD) is carried out at 80% of the battery capacity during the discharge process with variations in C-rates of 1 C, 1.5 C, and 2 C. The results show that the C-rate has a greater value, the temperature value released by the battery will also be greater. The negative pole, intermediate battery, and positive pole exhibit the characteristics of the battery pack’s surface temperature in order from highest to lowest throughout the discharge process. At the negative pole of the battery, the highest temperature in NC cooling is 30.1°C, 32.3°C, and 33.3°C can reduce this temperature to 28.8°C, 29.73°C, 31.8°C by SCIC with HFE-7100 liquid at DoD 1 C, 1.5 C, and 2 C respectively. Battery surface temperature characteristics based on channel position from highest to lowest using NC in the order of 6-3-2-4-5-1 and SCIC in the order of 6-5-4-3-2-1.
Effect of annealing time on the structural stability of LiCo0.55Ni0.4Ti0.05O2 cathode material via combustion method
Authors: Azahidi A , Kasim M F , Elong K , Kamarulzaman N
Published: December 2023

Layered LiNi1-xCoxO2 cathode material, particularly LiCo0.6Ni0.4O2 (LCN) in stoichiometry is one of the promising cathode materials as it possesses a good electrochemical behaviour and performances comparable with commercial LiCoO2 (LCO) cathode material. However, more improvement needs to be done in LCN cathode material in terms of higher toxic Co content and higher cation mixing in the material which mainly contributes to the structural instability and affects the capacity fading of the material. To combat both significant issues in the material, the stability of that material structure needs to be tackled first. In this study, Co was partially substituted with Ti4+ to give the LiCo0.55Ni0.4Ti0.05O2 (LCNT) cathode material using the combustion method. To get the optimum condition of LCNT, the precursor was then calcined at a temperature of 750°C for 24 hours, 48 hours and 72 hours and denoted as LCNT24, LCNT48, and LCNT72 respectively. XRD reveals that all samples are pure, single-phase with no impurities present except for LCNT72. Nano-sized LCNT24 sample has the highest RIR value of 1.84 indicating the lowest degree of cation Li+/Ni2+ mixing in the material and the most stable structure compared to others.
Nutritional value of sea cucumber Acaudina molpadiodes from Delta Wulan Estuary, Demak Regency, Central of Java, Indonesia
Authors: Widianingsih W , Hartati R
Published: December 2023

Sea cucumber Acaudina molpadiodes has a nutritional value that can be utilized as a functional food for humans. Therefore, this study aims to examine the composition of proximate, fatty acid, and amino acids in A. molpadiodes. The samples were collected from Delta Wulan Estuary, Demak Regency, Central Java, Indonesia. Based on the result of this study, the average value of moisture, protein, carbohydrate, total lipid, and ash contents in A. molpadiodes ranged between 90.44 – 91.23%, 4.44 – 4.97%, 4.12-4.35%, 0.16-0.18%, and 0.05-0.06% respectively. According to the result of amino acid analysis, the profile of essential amino acids comprised phenylalanine, isoleucine, valine, lysine, leucine, threonine, histidine, cysteine, methionine, and tryptophan. The average value of leucine content was 2273.95 ± 291.61 mg.kg-1, and the threonine content was 2732 ± 276.93 mg.kg-1. The non-essential amino acid profile consisted of glutamic acid, alanine, glycine, aspartic acid, tyrosine, proline, and taurine. The glycine and glutamic acid content in A. molpadiodes are 6843.67 ±393.71 mg.kg-1 and 5975.06 ± 687.85 mg.kg-1. Fatty acid profiles in A. molpadiodes are DHA (docosahexaenoic), EPA (Eicosapentaenoic acid), and AA (Arachidonic acid with an average value of 2.03 ±0.17 mg.100g-1, 2.42 ± 0.83 mg.100g-1, and 6.20±1.56 mg.100g-1.
Variation in Eastern Little Tuna (Euthynnus affinis) catches related to El Niño Southern Oscillation (ENSO) events in the Makassar Strait
Authors: Syamsuddin M L , Puspita A R , Syamsudin F , Ihsan Y N , Sunarto  , Zainuddin M
Published: December 2023

In order to determine how the El Niño Southern Oscillation (ENSO) affects Eastern Little Tuna catch rates in the Makassar Strait (MS), satellite-derived oceanographic variables, including sea surface temperature (SST), chlorophyll-a, salinity, sea surface height (SSH), ocean current, Niño index 3.4, and Eastern Little Tuna (Euthynnus affinis) catch data were used. Analyses were conducted for a seven-year period (January 2015-December 2021), which included the El Niño (2015) and La Niña (2021) events. A higher CPUE value is obtained in 2021 when La Niña occurs with a CPUE value of 3973 kg/trip, compared to the El Niño event. Based on seasonal variations, the highest catch was recorded during the northwest monsoon (706.02 kg/trip) with 2789 fishing points, while the lowest occurred during the southeast monsoon (700 kg/trip) with 2942 fishing points. The CPUE was 16.25 kg/trip with 1133 fishing points during El Niño and 23.56 kg/trip with 1027 fishing points during La Niña, respectively. The fishing grounds area was wider during the La Niña period, at 2 - 8°S and 115 - 120°E. This study revealed a strong impact of the La Niña events, significantly increasing Eastern Little Tuna catch in the MS.
The effect of continuous lighting on the rearing of yellowfin tuna (Thunnus albacares) larvae
Authors: Slamet Bejo , Hutapea Jhon H. , Gunawan  , Setiadi Ananto
Published: December 2023

Yellowfin tuna (Thunnus albacares) has important economic value in the world market. This study aims to determine the effect of continuous lighting on survival, growth, stomach contents, and histology of the eye of larvae. Larval rearing was conducted on 6 concrete tanks with 60 m3 in volume that support the water circulation and aeration system with an initial stocking of 20 eggs/liter. The treatments tested were A: Larval rearing by a 40-watt fluorescent lamp (TL) which was positioned 1 m above the surface of the water surface for 24 hours and B: Without lights (control). Each treatment used 3 repetitions and data analysis with a t-test. The parameters observed were larval survival and growth stomach content and eyes histology. The results showed that the rearing of larvae in treatment B can with a survival of 0.26±0.0231% and a final total length of 3 6.2 ± 7.3 mm which is significantly higher (P<0.05) compared to treatment A (0.10±0.057% and 24.3 ± 5.5 mm). From the observation of stomach contents at night in treatment B still eats rotifers while in treatment A stomach is empty. The inner nuclear layer cell arrangement of larval eyes is more tenuous than control. From these results, it can be concluded that the provision of continuous lighting treatment can improve the survival, growth, stomach content, and vision ability of larvae.
Performance Of Maintaining Brood Stock of Clarias gariepinus With Different Densities
Authors: Prabowo G , Kristiany M G E , Marlina E , Suhermanto A , Adi C A
Published: December 2023

African catfish is a type of fish that is favored by Indonesian people. In the cultivation, availability of broodstock determines the success rate of production. A well-managed of broodstock will produce high productivity. Productivity is measured from the time interval of broodstock required to produce eggs after spawning, the fecundity and hatching rate. The density of broodstock will affect on productivity. This study aims to determine the right broodstock density in order produce eggs continously. The main container used is a cement tank with dimensions of 1 × 1 m2and 1,2 m depth. The broodstock were reared in a recirculating system with stocking densities of 5, 10 and 15 fish/m2. Each treatment was repeated in 3 times. During maintenance, the number of broodstock was fed with floating pellets at 3% per day with the provision of 2 times every day. The results of water quality measurements as supporting data include temperature, pH, ammonia, nitrite and nitrate. Productivity was measured during 3 months of rearing to determine the egg production cycle. The productivity of broodstock with a stocking density of 15 fish/m2resulted in a faster gonadal maturity level. However, the resulting fecundity, Fertilization Rate and Hatching Rate were better at the number of stocking 10 and 5 fish/m2.
Physical, chemical and sensory properties of cookies added with Arthrospira platensis granules and stevia sugar
Authors: Raharjo S , Ekantari N
Published: December 2023

Cookies can be supplemented with the protein, fatty acids, vitamins, and minerals present in Arthrospira platensis, however adding the powder alters the product’s flavor, color, and aroma. Granulating the powder, which has the benefit of not being easily soluble in the dough, is one technique to reduce the fishy smell and flavor and boost consumer acceptance. Stevia sugar is used in this study to make low-calorie cookies in place of sucrose sugar. This study conduct to ascertain how the inclusion of Arthrospira granules and stevia sugar affected sensory qualities and levels of customer acceptance. The study 2×4 totally random design included stevia sugar replacement (30%; 50%) and granule addition (3%; 6%; 9% (w/w dough)) with 0% serving as the control. The results showed that stevia sugar affected swelling volume and that granules affected granule appearance, color, and flavor. A follow-up test was carried out because, with sensory averages of like-really like, the G1S1 (3% granules: 30% stevia) and G1S2 (3% granules: 50% stevia) treatments were not significantly different based on hedonics. Although the ash content was not considerably different, the water content and overall sugar content were. In the depth investigation revealed that 3% of granules can be added to arthrospira to lessen its fishy flavor. The Time Intensity results show that G1S1 treatment produces the best Arthrospira platensis granula cookies that can be utilized as an alternative functional food, whereas G1S2 treatment produces a very bitter aftertaste.
Direct numerical simulations on oscillating flow past surface-mounted finite-height circular cylinder
Authors: Kumar Abhishek , Kumar Prashant , Tiwari Shaligram
Published: December 2023

In this work, a surface-mounted circular cylinder with a fixed aspect ratio (ratio of height of the cylinder to its diameter) of 5 is subjected to a non-zero mean oscillating flow with a range of frequencies and amplitudes. Three-dimensional direct numerical simulations are then conducted on this finite-height cylinder. The mass and momentum equations are resolved using the finite volume-based Open Source Field Operation and Manipulation (OpenFOAM). A fixed Reynolds number

Re

=

U
o

D

/

ν

of 250 is used in this study, which is defined based on mean velocity at the inlet (

U
o

) and cylinder diameter (D). Here

ν

is the kinematic viscosity of the working fluid. Non-dimensional velocity oscillation amplitude (

A

∗

=

a

/

U
o

) is varied from 0.1 to 0.3, while the non-dimensional oscillation frequency (

f

∗

=

f

/

f
o

) takes the values of 0.33, 0.5, 1, 2, and 3. Here a and f are the dimensional oscillation amplitude and frequency, respectively and

f
o

is the vortex shedding frequency corresponding to a uniform flow at Re = 250. The three-dimensional vortex structures, presented with the help of iso-Q surfaces, show that the oscillating flow changes the size and shape of the hairpin-shaped vortices. Wake is found to be synchronized with the oscillation frequency at f* = 2 for each value of the A* and results in the maximum lift force on the cylinder. Hilbert Huang transformation analysis of the transverse velocity signals at a specific point in the wake reveals that the wake is more complex and aperiodic in nature for f* values of 0.33, 0.5, and 1, whereas it is periodic for f* = 2 and 3. In order to further disclose the nonlinearity associated with the oscillating flow, the degree of stationarity is discussed corresponding to each value of A* and f*. Dynamic mode decomposition is exploited to obtain information about the coherent vortical structures and their spatial and temporal behavior in the wake with a change in the value of f*. Effects of A* and f* on the dynamic characteristics are also investigated.
Study on interfacial morphologies of AA1060 and SS321 magnetic pulse welded joints
Authors: Su Shan , Wang Yiming , Wu Yuanyuan , Wang Ruichen
Published: December 2023

In this study, the application of magnetic pulse welding was employed for the production of tubular joints using 1060 aluminium and 321 stainless steel. Two crucial process parameters, the charging voltage, and the gap between the outer and inner tubes, were subjected to mechanical property tests and morphology analysis. The joints that exhibited favourable mechanical properties were obtained with a gap size of 1.25 mm and a charging voltage exceeding 3.5 kV. The presence of intermetallic compounds at the joint interface indicates the occurrence of fusion in the transition zone. The quantity of molten metal increased with an increase in the charging voltage. The aluminium content in the intermetallic compounds within the transition zone decreased as one moved from the 1060 aluminium side towards the 321 stainless steel side. The gap distance plays an important role in determining the efficiency of energy transformation at the joint interface during magnetic pulse welding (MPW). A smaller gap distance resulted in a substantial amount of energy being transformed into plastic deformation in the transition zone. Conversely, a greater gap distance led to a significant amount of energy from the electrical charging voltage being converted into thermal energy. The MPW joint consisted of bonding, mechanical interlock, and non-bonding regions. The mechanical properties of the joint were influenced by the composition of the intermetallic compound. Taking into account the impact of morphologies and elastic modulus of the transition zone, an increase in the melting of stainless steel during the welding process was found to be advantageous for the MPW of 1060 aluminium to 321 stainless steel.