bluuebunny/crossref_metadata_2025 huggingface dataset:
Attenuation proxy hidden in surface brightness – colour diagrams
Authors: Małek K. , Junais  , Pollo A. , Boquien M. , Buat V. , Salim S. , Brough S. , Demarco R. , Graham A. W. , Hamed M. , Mullaney J. R. , Romano M. , Sifón C. , Aravena M. , Benavides J. A. , Busà I. , Donevski D. , Dorey O. , Hernandez-Toledo H. M. , Nanni A. , Pearson W. J. , Pistis F. , Ragusa R. , Riccio G. , Román J.
Published: February 2024

Aims. Large future sky surveys, such as the Legacy Survey of Space and Time (LSST), will provide optical photometry for billions of objects. Reliable estimation of the physical properties of galaxies requires information about dust attenuation, which is usually derived from ultraviolet (UV) and infrared (IR) data. This paper aims to construct a proxy for the far-UV (FUV) attenuation (AFUVp) from the optical data alone, enabling the rapid estimation of the star formation rate (SFR) for galaxies that lack UV or IR data. This will accelerate and improve the estimation of key physical properties of billions of LSST–like observed galaxies (observed in the optical bands only).

Methods. To mimic LSST observations, we used the deep panchromatic optical coverage of the Sloan Digital Sky Survey (SDSS) Photometric Catalogue, Data Release 12, complemented by the estimated physical properties for the SDSS galaxies from the GALEX-SDSS-WISE Legacy Catalog (GSWLC) and inclination information obtained from the SDSS Data Release 7. We restricted our sample to the 0.025–0.1 spectroscopic redshift range and investigated relations among surface brightness, colours, and dust attenuation in the FUV range for star-forming galaxies obtained from the spectral energy distribution (SED).

Results. Dust attenuation is best correlated with colour measured between u and r bands (u − r) and the surface brightness in the u band (μu). We provide a dust attenuation proxy for galaxies on the star-forming main sequence. This relation can be used for the LSST or any other type of broadband optical survey. The mean ratio between the catalogue values of SFRs and those estimated using optical-only SDSS data with the AFUVp prior calculated as ΔSFR = log(SFRthis work/SFRGSWLC) is found to be less than 0.1 dex, while runs without priors result in an SFR overestimation larger than 0.3 dex. The presence or absence of the AFUVp has a negligible influence on the stellar mass (Mstar) estimation (with ΔMstar in the range from 0 to −0.15 dex).

Conclusions. We note that AFUVp is reliable for low-redshift main sequence galaxies. Forthcoming deep optical observations of the LSST Deep Drilling Fields, which also have multi-wavelength data, will enable one to calibrate the obtained relation for higher redshift galaxies and, possibly, extend the study towards other types of galaxies, such as early-type galaxies off the main sequence.
Shocks, clouds, and atomic outflows in active galactic nuclei hosting relativistic jets
Authors: Perucho Manel
Published: February 2024

Context. A number of observations have revealed atomic and/or molecular lines in active galaxies hosting jets and outflows. Line widths indicate outward motions of hundreds to a few thousands of kilometers per second. They appear to be associated with the presence of radio emission in Gigahert-peaked spectrum (GPS) and/or compact steep spectrum (CSS) sources, with linear sizes of ≤10 kpc. Numerical simulations have shown that the bow shocks triggered by relativistic jets in their host galaxies drive ionization and turbulence in the interstellar medium (ISM). However, the presence of atomic lines requires rapid recombination of ionized gas, which appears challenging to explain from the physical conditions revealed thus far based on numerical simulations of powerful jets.

Aims. The aim of this paper is to provide a global framework to explain the presence of lines in terms of jet and shock evolution and to fix the parameter space where the atomic and molecular outflows might occur.

Methods. This parameter space is inspired by numerical simulations and basic analytical models of jet evolution as a background.

Results. Our results show that a plausible general explanation involves momentum transfer and heating to the interstellar medium gas by jet triggered shocks within the inner kiloparsecs. The presence of post-shock atomic gas is possible in the case of shocks interacting with dense clouds that remain relatively stable after the shock passage.

Conclusions. According to our results, current numerical simulations cannot reproduce the physical conditions to explain the presence of atomic and molecular outflows in young radio sources. However, I show that these outflows might occur in low-power jets at all scales and I predict a trend towards powerful jets showing lines at CSS scales, when clouds have cooled to recombination temperatures.
Analysis of the concept of circular economy application by small and medium industries in West Java province (a case study: Padamukti and Cibodas villages, Solokan Jeruk district, Bandung regency)
Authors: Nur Yudha Hadian , Sutadian Arief Dhany , Putra Nurjaman Gunadi , Nastiti Anindrya
Published: February 2024

Although small and medium enterprises (SMEs) have played an important role in Indonesia’s economic growth, they bring various environmental problems. SMEs in the manufacturing sector, also known as small and medium industries (SMIs) are the majority of business entities in Indonesia and are one of the most significant polluters. This study focused on several SMIs located within two villages (i.e. Padamukti and Cibodas) alongside the Citarik River, which is one of the Citarum River tributaries. The study aimed to identify the concept of circular economy application by SMIs in West Java Province consisting of an understanding of (1) the circular economy concept and (2) internal and external factors of the circular economy application. In this study, we applied the snowball technique, closed questionaries, strengths-weakness-opportunities-threats (SWOT), and quantitative strategic planning matrix (QSPM). There were 10 selected respondents, including 4 respondents who were waste generators, while 6 respondents were classified as waste beneficiaries. The study found that 100% of the involved respondents had never heard or understood the concept of the circular economy even though they had partially applied the 5R principles. By using SWOT, driving and barrier factors were identified. The reprocessed waste became a strength factor, while the lack of knowledge and expertise in waste management were two major weaknesses. Meanwhile, there was attention and encouragement from the government for SMIs that implement environmentally friendly businesses as an opportunity factor, and insufficient market availability or consumers are part of the external analysis. Sequentially, using QSPM we suggest that socialization of the circular economy concept needs to be carried out in the wider community as the priority strategy and policy recommendations, followed by policymaking and guidelines for effective circular economy implementation.
Unravelling the effects of temperature shifts on microbial communities and biogas production of digested sewage sludge anaerobic digestion
Authors: Wiguna Sudiartha Gede Adi , Tsuyoshi Imai
Published: February 2024

Anaerobic digestion (AD) is an effective method to generate renewable energy from domestic wastewater via biogas production. AD is heavily dependent on temperature since it impacts the microbial communities, which in turn determines the stability of the AD process. This study investigated how microbial community structure changed during a stepwise temperature upshift from 37 °C to 41 °C in fed-batch serum vials using digested sewage sludge as inoculum and glucose-based substrate. Results showed that there was a 9% decrease in methane production when the temperature was shifted from 37 ºC to 39 ºC. Despite the lower methane yield, the methane content at 39 ºC is higher than the content at 37 ºC, followed by a 41% decrease in CO2 production. This condition indicates the activity of hydrogenotrophic Methanobacterium that consumed CO2 to produce methane and syntrophic Acetomicrobium that consumed CO2 to produce acetate to support acetoclastic methanogen, which was dominated by Methanothrix. The abundance of methanogens declined significantly after the temperature was shifted to 41 ºC followed by a decrease in biogas production. These findings exhibited how in a certain range of temperatures; the growth of methanogens was inhibited which further led to the decline in overall biogas production despite the versatility of syntrophic acetogens as their supports.
Bioavailability enhancement of petroleum-contaminated soil by electrokinetic remediation
Authors: Madonna Sandra , Effendi Agus Jatnika , Kardena Edwan , Hidayat Syarif
Published: February 2024

The Electro kinetic Remediation Technology (EKR) is recognized as the most potential remediation technology for soils with low permeability, like clay soil characteristics. Electrokinetic treatment could increase the bioavailability of contaminants in bioremediation petroleum-contaminated soil. The study, “Bioavailability enhancement of petroleum contaminated soil by electrokinetic remediation,” is experimental research in a laboratory to improve the bioavailability of petroleum hydrocarbons on clay during bioremediation with initial treatment using electrokinetic remediation techniques, finding optimum electrokinetic operating conditions of remediations, and analyzing the mechanism of remediation process in contaminated soil. Bioavailability enhancement was studied for 35 days. Polluted soil was treated with an electrokinetic box test (17cm×12cm×10cm), and DC power was used for 48 hours. Total Petroleum Hydrocarbon (TPH) concentration was determined by gravimetric methods. The results showed that the characteristics of the soil samples were dominated by 49.31% clay. The initial concentration of TPH in polluted soil is 3.7%. The electrokinetic applications during 48 hours and followed by bioremediation for 35 days those processes removed TPH up to 80.74 % (from 33780.66 mg HC (kg dry w)-1 to 6506.155176 mg HC (kg dry w)-1. There is an increase in bioavailability indicated by the rise in bacterial populations and an increase in biodegradation after electrokinetic remediation. With this approach, bioavailability has been increased by 70.18%. Bio-electrokinetic remediation is the recommended method for polluted clay soils with low bioavailability.
Analysis of the potential and characteristics of Nipa(Nypa fruticans)as a sustainable biofuel alternative source in Indonesia
Authors: Prasetyo Cahyo Purnomo , Effendi Agus Jatnika , Chaerul Mochammad
Published: February 2024

A sustainable energy source, one that doesn’t compete with food production, is crucial for enhancing national energy independence. This study assesses the feasibility of Nipa palm (Nypa fruticans) as a biofuel source in Indonesia. The research involved vegetation and laboratory analyses to determine Nipa palm’s potential for biofuel production. The results revealed a Nipa density of 3,167 trees ha-1with a mesocarp yield of 3.99 tons ha-1and sap yield of 177.35 kL ha-1. The mesocarp contains 39.37% carbohydrates, and the sap has a total sugar content of 13.13%. National estimates for mesocarp and sap production were 3,339,630 tons year-1and 148,443 thousand kL year-1, respectively. Estimated bioethanol production from Nipa sap was 13,330 thousand kL year-1. Incorporating Nipa bioethanol into the national fuel supply would increase it to 66,766 thousand kL year-1(24.95%), while reducing imports to 14,531 thousand kL year-1(47.86%). In conclusion, Nipa palm offers significant advantages as a potential biofuel feedstock, particularly for bioethanol production, without compromising food supplies.
Assessing compliance with environmental regulations: A case study of fines imposed on companies in the Citarum River Basin, Indonesia
Authors: Mayangsari Miranti , Nastiti Anindrya , Marselina Mariana , Astriani Nadia , Wibisana Andri Gunawan
Published: February 2024

The Indonesian Government has established targets for law enforcement concerning pollution loading and environmental damage, as regulated by the Regulation of the Minister of Environment (MoE) of the Republic of Indonesia 7/2014. Several cases of non-compliance with environmental laws have been processed in the Citarum River basin, resulting in varying fines being imposed. This research examines how much fines imposed on non-compliant companies align with the provisions outlined in the MoE Regulation 7/2014. Additionally, the study compares the fines with the capital required for establishing proper wastewater treatment plants and implementing comprehensive hazardous waste management. Based on data obtained from court evidence and decisions, this paper employs descriptive analysis to understand the current sanctioning and calculation of fines in multiple cases of environmental law non-compliance in the Citarum River, focusing on the textile industry. The findings from two civil cases of non-compliance reveal that the determination of sanctions does not consider the costs associated with environmental restoration and ecosystem loss. In those civil lawsuits, 99% of fines imposed only consist of losses caused by exceeding the environmental quality standard. In criminal cases, fines applied only cover approximately 8.37% of the total hypothetical WWTP operational cost and sludge handling (for wastewater discharge debit 100 m3 per day) and 0.84% of the total hypothetical WWTP operating cost and sludge handling (for wastewater discharge debit 1000 m3 per day). Based on the findings, we argue that the fines in civil and criminal cases for textile industries in the Citarum River Basin are still insufficient.
Learning environments for multi-stakeholder participation in water management: Visual Problem Appraisal Citarum River
Authors: Fliervoet Jan , Witteveen Loes , Roosmini Dwina , Geerling Gertjan , Nastiti Anindrya , Mansoor Alvanov Z.
Published: February 2024

Sustainable management of the Citarum River is a complex problem due to climate challenges such as increase of extreme weather events, as well as by increased anthropogenic activities leading to water pollution, waterborne diseases and floods. To act on this, active engagement of diverse stakeholders in decision-making for integrated water management is needed to share knowledges and understand diverse perspectives. This research reflects on the potential of the Visual Problem Appraisal (VPA) methodology to facilitate stakeholders’ participation in the complexity of sustainable water management in Indonesia. A VPA consists of a series of filmed interviews allowing stakeholders to express their concerns and issues. The interviews are used in thematic workshops to enhance dialogue and stimulating social learning in complex multi-stakeholder settings, in order to enhance environmental governance. Using the VPA solves two well-known problems: shortage of time and means for stakeholders to participate (stakeholder fatigue) and the fact that often the same people participate in diverse arenas (the usual suspects). The VPA could be used at ITB for bachelor’s and master’s degrees regarding Environmental Engineering, at Dutch universities and as a method to facilitate mediated participation within the Living Lab Upper Citarum.
Assessing the carbon footprint of drinking water supply system in Indonesia: A case study of the Rebana Metropolitan Area
Authors: Sudradjat Arief , Azizah Jihan N.
Published: February 2024

The development of the Rebana Metropolitan Area in the northern region of West Java aims to improve the economy in the area with improved infrastructure, including safe drinking water provision through a sustainable drinking water supply system (SPAM) that aligns with low-carbon development in Indonesia. This study presents a comprehensive assessment of the carbon footprint associated with SPAM. A dynamic system modeling approach was employed to calculate SPAM’s carbon footprint, considering key activities such as drinking water supply through piped networks and wells, bottled water distribution, potable water provision through refillable drinking water depots, and drinking water boiling. The model was calibrated and validated using data from Indramayu Regency, demonstrating its accuracy with an RMSPE value of 0.03% for the population and 4.89% for water treatment plant production capacity. By utilizing data from industrial zones (KPI) Patrol and Losarang, the model simulations revealed that under business as usual (BAU) conditions, the projected carbon footprint of SPAM in 2040 was 332,194 tCO2eq. To explore effective intervention strategies, three scenarios (I, II, and III) were simulated, incorporating different rates of wastewater recycling—10%, 20%, and 30% by 2030, respectively. The results demonstrated that implementing these scenarios would lead to reduced SPAM’s carbon footprints in 2040, with projected values of 283,275 tCO2eq, 246,586 tCO2eq, and 225,184 tCO2eq for scenarios I, II, and III, respectively. Bottled water exhibited the highest carbon footprint per unit volume of 28.847 kgCO2eq/m3.
Design and development of serious games for future proof peatland management: Option for virtual Living Labs
Authors: Witteveen Loes , Roosmini Dwina , Mansoor Alvanov , van der Maas Peter , Mahmud  , Horsten Brechtje , Blankestijn Wouter , Verspui Walter , Iriana Windy , Fliervoet Jan
Published: February 2024

Worldwide, including Indonesia and the EU, current (agricultural) use in peatlands is based on massive water drainage. Because drainage leads to environmental problems, many scholars, policy makers and (agricultural) entrepreneurs are rethinking peatland use, aiming for more sustainable peatland management, based on rewetting. However, policymakers and governments often hesitate to implement measures in practice, because rewetting peatlands could have massive socio-economic impacts. Serious Gaming (SG) can facilitate the transition to more sustainable use of peat areas because it provides a safe environment in which social and physical impact of choices can be simulated and evaluated. The SG website http://peatland.eu/ aims to contribute to transition processes for sustainable futures by exploring processes of communication, participation, and social-ecological learning in peatland initiatives. Envisioning a similar impact of this virtual Living Lab it is the ambition to design http://peatland.asia/ and thereby provide a learning strategy for Higher Education Institutes and other interested parties. Achieving such strategy requires a transdisciplinary approach to meet user experience and interface requirements, scientific validity, and contemporary relevance. This paper explores both websites in a context of a collaborative initiative to engage a diversity of peatland colleagues in the further development of interactive relevance of the website.
Reliability study of raw water in the Krueng Aceh River for Banda Aceh City piped drinking water service system development
Authors: Marselina Mariana , Aulia M. Mirza , Sabar Arwin
Published: February 2024

Increasing population leads to higher demand for clean water. Clean water supply in Banda Aceh City is entrusted to the Tirta Daroy Water Supply Company with a capacity of 730 l/s with raw water sources from the Krueng Aceh River, Krueng Aceh Watershed. Master Plan of the Banda Aceh City Drinking Water Supply System 2015 was planned to increase production capacity by 1,916 l/s by 2035. So, a reliable raw water resources are needed to meet the increase in production capacity of 1,186 l/s. The reliability of raw water resources can be attempted by statistical analysis of minimum successive dry discharge data of duration 1,2,7,15, and 30 days with theoretical distribution fit tests carried out. The types of distributions used to analyze extreme dry discharge are the Gumbel, Log-Normal, and Log-Pearson III distributions. From the results, the Krueng Aceh River can meet the raw water sources needs until 2035 with the dependable flow of QR20-1 = 4.74 m3/s. Increasing production capacity is planned by building a processing plant at two stages, 800 l/s and 400 l/s.
Water availability of Akelamo River, Obi Island, South Halmahera
Authors: Yasya Heksantia Rahmadinda , Abfertiawan Muhammad Sonny , Gultom Tonny H. , Gunardi Petrus , Syahroni Muharwan
Published: February 2024

The nickel mining industry’s activities are not spared from the high quantity of water demand, such as those of Harita Nickel Indonesia, a company located in Obi Island, South Halmahera. As one of the largest nickel mining companies that uphold environmental conservation, Harita Nickel Indonesia conducted this study to identify and analyze water availability to ensure the company’s and local residents’ water needs. One of the water resources in this study is Akelamo River, which has a 254.99 Km2 catchment area (covering the catchment area of Karo Lake upstream). Referring to SNI 6738:2015, water availability can be indicated by the amount of dependable flow based on an 80% probability of occurrence. This calculation is carried out using F.J. Mock method that heavily relies on six (6) defining variables: Reflection coefficient (r), Exposed surface (m;%), Soil moisture capacity (ISMC), Infiltration coefficient (if), Flow recession constant (k), and Percentage factor (PF). Based on the method and conditions of this location, it is calculated that the dependable flow Q80 of the Akelamo River is 6.2 m3/sec. It should be noted that this figure only represents overflow discharge and does not include the amount of water currently stored in the water body. This availability study can be continued with a water balance analysis according to the planned water demand or even as a consideration in hydrological infrastructure planning such as dams.
The challenges in implementing the environmental flow concept in Indonesia
Authors: Nugroho Adam Rus
Published: February 2024

Environmental flow or ecological flow is a term used to define the minimum or optimal flow a stream should attain. It has begun to be adopted by many countries in the last two decades. Environmental flows contribute to freshwater conservation and all aspects it derives. Water for the environment is an aspect that plays an important role in maintaining sustainable development. However, environmental flow is still not well-known and not well-implemented in Indonesia, as indicated by its low research interest and minimal regulation in Indonesia. Therefore, this study shows the challenges of implementing the concept of environmental flow in Indonesia while at the same time also promotes the concept. This literature study highlights the typical issues of implementing the environmental flow policy reported from various countries. The global issues then compared to Indonesian characteristics. The factors that limit the implementation in Indonesia concluded as: competing priorities, lack of visibility, lack of awareness, and lack of data. These limitations become challenges in conserving water for the ecosystem, especially when the Indonesian government still struggles to satisfy access to clean water and tackle the problems of water pollution. Despite the constraints and challenges, we must preserve freshwater systems to achieve sustainable development.
Analysis of the presence of the blaCTX-M genes in Escherichia coli isolated from downstream of the Bekasi River
Authors: Gusti Lathifah Hana , Priadi Cindy Rianti , Rahmatika Iftita , Paramitadevi Yudith Vega
Published: February 2024

Antimicrobial resistance (AMR) is a global public health threat caused by antibiotic resistance genes (ARGs), such as blaCTX-M. The blaCTX-M is one of the most common ARGs that confers cephalosporin resistance. This study aimed to investigate the concentrations of cefotaxime-resistant Escherichia coli (E. coli) and the presence of the blaCTX-M in E. coli isolated from downstream of the Bekasi River. The results of this study provided some information on AMR in reservoir environmental bacteria. This study used polymerase chain reaction (PCR) to amplify DNA and gel electrophoresis to visualize the target genes. The results are downstream of the Bekasi River had an average concentration of non-selective E. coli (2,3 ± 0,4) × 104 CFU/100mL and the average concentration of cefotaxime-resistant E. coli (2,1 ± 0,6) × 103 CFU/100 mL. The ratio of antibiotic-resistant E. coli to non-selective E. coli was 9.4%. The blaCTX-M genes were detected in 80% of E. coli isolates, with blaCTX-M group 1 genes predominating, which includes the blaCTX-M -1, blaCTX-M-3, and blaCTX-M-15 genes.
Designing web-based designed for decision making process of upgrading slum sanitation
Authors: Apriadi Dian Permatasari , Barjenbruch Matthias , Soewondo Prayatni
Published: February 2024

In Indonesia’s slum areas, Inadequate sanitation is a major challenge. This study introduces an interactive web-based platform, UPSS (“Upgrading Slum Sanitation”), to aid in selecting appropriate sanitation technologies for these regions. UPSS integrates a Decision Support System (DSS) to streamline the decision-making process. Our objective was to create UPSS to facilitate the selection of suitable sanitation technologies, tailored to the specific needs of Indonesia slum areas. We employed a mixed-methods approach to develop UPSS, focusing on user-friendly interfaces and streamlined decision-making processes. The first screen will help identify the slum classification (high, middle and low slum) by using the questionnaire. The following screens will identify alternative sanitation technologies. After that we apply the UPSS in the case study area, Manado Indonesia. The application of UPSS in slum areas of Indonesia demonstrated its effectiveness in reducing planning time for sanitation improvement. The results, presented in an easily interpretable format, showed a range of sanitation options and were well-received by facilitators in these areas. UPSS proves significant in improving sanitation planning in slums. It offers a quick, efficient, and user-friendly tool for stakeholders to identify and implement the most suitable sanitation technologies, thereby addressing a critical need in urban sanitation management
Development and validation of instrument to measure citywide inclusive sanitation (CWIS Scale) for Low-and Middle-Income Countries (LMICs)
Authors: Safira Khansa Fay’i , Nastiti Anindrya , Kurniati Ami Santika , Sakti Anjar Dimara
Published: February 2024

Universal access to safe and adequate sanitation is a critical public health and environmental issue, particularly in low-income urban areas. The Citywide Inclusive Sanitation (CWIS) approach seeks to address the challenge of meeting the universal access to sanitation for all, including the most vulnerable groups. The six key criteria in CWIS are: (1) equity; (2) safety; (3) sustainability; (4) responsibility; (5) accountability; and (6) Resource Planning and Management. This study aimed to develop and validate survey instruments for CWIS measurement in urban areas of Low- and Middle-Income Countries (LMICs). First, we specified the domains based on the six CWIS criteria by, adding the vulnerability criterion to the equation. We developed candidate items for each domain by reviewing the relevant literature. Face validity was determined through cognitive interviews, and content validity was determined through the evaluation of two experts. We added, removed, merged, and rephrased items based on the results of cognitive interviews and feedback from subject matter experts. We piloted the instrument and conducted statistical analysis to ensure the validity and reliability of the ‘scales and indices. The CWIS survey modules address a recognized need for greater emphasis on inclusive sanitation. We provide researchers and policymakers with tools to measure CWIS sub-constructs in a valid and reliable manner to generate data for improved targeting, design, implementation, and evaluation of strategies to improve sanitation access for vulnerable and marginalized urban citizens.
Image processing techniques for measuring primary microplastic abundance in various of dispersant
Authors: Maula Rahmatun , Zevi Yuniati , Hakiki Rijal , Muntalif Barti Setiani , Daniar Putri Sandi
Published: February 2024

Microplastics have become one of the world’s most important environmental issues and have received widespread attention as a new type of pollutant. Microplastic quantification methods have evolved from manual to semi-automated and automated methods. These methods still possess drawbacks such costly detecting equipment, lengthy detection durations, and imprecise detection rates, making the detection of microplastics difficult in natural environments. This study aimed to measure the abundance of primary microplastics (microbeads) using Image Processing Techniques (IPT) with various dispersants and validated them using microscopy. Plugable Digital Viewer v.3.1.07 software was used to capture digital images of the IPT tool, while the microscope used Obtilab viewer 3.0. The IPT results were processed and analyzed using ImageJ 1.53t software. The originality of this study is that digital images were taken directly in liquid samples with the preparation sample dispersant so that microplastics in surface water could be directly quantified and identified. This study provides a very strong correlation between the sample mass and particle counting, as seen from R2>0.75. A statistical test of the data obtained (P-Value>0.05) demonstrated a normal distribution of the data. The t-test results between each mass variation obtained (P-Value <0.05) indicated that the microplastic particles from each mass variation were different. The LoD for PP and PE were 1.75 and 0.00009 respectively while the LoQ were 28.5 and 39.5. The %recovery from 10 repetitions produced consistent values for PP and PE, which had less stable values obtained at 0% in repetitions 1.5 and 8. The %RSD from 10 repetitions was below 40%.
Analysis of fecal pollution load factor from septic tanks of residential area (study case: Bandung City, Indonesia)
Authors: Firdayati Mayrina , Hasibuan Munira Afina , Abfertiawan Muhammad Sonny
Published: February 2024

According to the Ministry of Environment and Forestry, 2017, domestic waste is the most significant contributor to pollution sources in the Citarum watershed (62.16%) and Bandung City (94.15%). To overcome the problem, planning for infrastructure development and improvement of the domestic sewage treatment system is necessary. One of the essential characteristic parameters, which is the subject of this study, is the pollutant load factor parameter in the city of Bandung. Compared to sewage pipelines, the domination of domestic wastewater treatment in Bandung is the On-site Sanitation System (OSS) (38.47%), and the most widely used type of OSS is a septic tank. For this reason, thirty fecal sludge samples were taken from two fecal disposal points in Bandung City, and the concentrations of TSS, COD, BOD, and Ammonia were then analyzed. Based on the results of the study, the range of fecal sludge pollutant load factor for TSS in Bandung City is 57.28 g / person/day – 1,064 g / person/day with an average value of 546.39 g / person/day, the range for total COD is 30.06 g / person/day – 294.99 g /person/day with an average of 294.99 g / person/day, the total BOD range is 14.05 g /person/day – 504.97 g / person/day with an average of 175.5 g / person/day, and ammonia range 1.61 g/person/day – 3.11 g/person/day with an average of 2.62 g/person/day. Based on fecal sludge data, the result can be considered a recommendation to re-determine the main domestic wastewater pollution indicator generation. The new suggestions can be used to design an adequate domestic wastewater treatment system, especially in Bandung. The pollutant load factors can also be used to estimate the pollution loading of wastewater generated by present and future populations. It is important in urban growth planning.
Evaluation of psychosocial factors affecting faecal sludge desludging practice compliance in Bekasi City
Authors: Putri Dyah Wulandari , Amadea Josephine
Published: February 2024

Desludging operators have important role in on site sanitation to achieve safe sanitation. Desludging practice have to comply with the principles of safe sanitation and regulations to maintain the health and safety of the worker, the community, and the environment. However, the implementation of desludging sometimes does not comply with safe sanitation principle and regulation. This study aims to identify the compliance of faecal sludge desludging with regulation and safe sanitation principle. Furthermore, Theoretical Domains Framework (TDF) is applied to explore psychosocial factors of the operators that affect desludging practice. Questionnaire assessing desludging practice and psychosocial factors based on TDF was given to 32 desludging operators that works in local government and private desludging services in Bekasi City. Desludging practice in Bekasi City were not comply desludging practice procedure. From desludging procedure compliance, only 56% of the respondents claimed to have carried out the desludging practice in accordance with the procedures, low percentage also found in the worker’s safety procedure especially in wearing Personal Protective Equipment (PPE) eventhough mostly do not do high risk action in emptying. Related to faecal sludge disposal procedure, high percentage (84%) of workers always discharge to Faecal Sludge Treatment Plant (FSTP), while some small amount (16%) often follow the discharge procedure. Spearman’s Rank Correlation analysis was used to determine domains in TDF that significantly affecting desludging practice compliance. From the correlation analysis, Knowledge (ρ = 0.505; P =0.003), Beliefs about consequences (ρ =0.473; P = 0.006), and Environmental context and resources (ρ =0.389; P = 0.028) are statistically significant affecting desludging practice.
Development of an economically viable plastic recovery waste management system in Cibodas and Padamukti Village, West Java
Authors: Purnomo Carissa Eukairin , Priadi Cindy Rianti , Ombasta Osha , Suwarso Reni , Marthanty Dwinanti Rika , Taufik Farhan Dzakwan , Holden Jane , Hadfield Paris
Published: February 2024

Out of the 2,142 existing community-managed sorting and recycling facilities in Indonesia, known as TPS-3R, only 14% are functioning optimally due to economic challenges, highlighting the need for financially viable TPS-3R. To address this issue, the research aims to recommend an economically viable plastic recovery waste management system with optimum residue and income. Cibodas and Padamukti Villages are chosen as the case study location, as it has only 20% waste collection coverage and is located in the Citarum Watershed, whose river is a source of water for 60 million people and is part of the Citarik Ecotourism Living Lab. Primary data collection was carried out through interviews with recyclers in the villages and through waste volume and composition characterization. Three scenarios were developed for the Plastic Recovery Facility (PRF) objectives: Scenario 1 (S1) serves as the baseline of PRF, Scenario 2 (S2) buys plastic wastes from existing traders to be processed with more advanced plastic recycling technologies, and Scenario 3 (S3) is a self-sustaining PRF that could be replicated for the whole villages. Data analysis involved mass balance, financial models, BCR, NPV, and multicriteria decision-making. The residue disposed of in landfills is 32%, 17%, and 28% of the total waste managed for S1, S2, and S3. Financial modeling yielded BCR values of 1.06, 1.15, and 1.24, as well as NPV +IDR78,036,332; +IDR465,224,754; and +IDR354,414,072. The results highlight the importance of detailed analysis of mass balance and financial modeling according to the waste composition in any TPS-3R location, especially the differences in the value of rigid and flexible plastics, which will affect the types of technology and products. While the recommended scenario, S3, does not eliminate the need for capital investment from the government, it provides a framework to plan PRF with an operating surplus, which will increase the community’s willingness to run it and ensure the PRF’s long-term functionality to yield social and environmental benefits.
Measurement of motorcycle exhaust emissions on urban roads using remote sensing
Authors: Gantina Tina Mulya , Lestari Puji , Arrohman Maulana Khafid , Mahalana Aditya , Dallmann Tim
Published: February 2024

This study aim to determine motorcycle exhaust emissions and emission factors on urban roads using unintrusive roadside remote sensing equipment, specifically the ETC M752 type version 3.1 from 2020. The research gathered 1012 valid and identified vehicle samples from five locations, comprising four in Jakarta and one in Bandung. The results unveiled median motorcycle emissions: CO2 (13.90%), CO (1.42%), smoke (0%), HC (1499 ppm), and NOx (2447 ppm). These measurements were recorded at an average speed of 21.81 km/h with an average acceleration of 0.05 m/s². Meanwhile the emission factors determined from this study were: 46.50 g/km, 1.95 g/km, 0 g/km, 0.22 g/km, and 0.46 g/km for CO2, CO, soot, HC, and NOx, respectively. An increase in the production year of motorcycles led to a significant reduction in exhaust emissions and emission factors. Across all production year categories, CO and HC emissions remained within acceptable thresholds. CO and HC emission factors already meet Euro 3 standards, while the NOx emission factor still does not meet the standard. Enhancing engine cylinder capacity resulted in a slight uptick in motorcycle exhaust emissions and emission factors. Specifically, the CO and HC emissions on Yamaha motorcycles are lower compared to Honda, while the NOx emissions on Yamaha motorcycles are higher compared to Honda. However, both brands have met Euro 3 standards for CO and HC but not for NOx.
Evaluation of detached plume and total organic carbon in the main chimney of the Indocement Plant 9-10 Palimanan to optimize clinker production and its influence on SO2 emissions
Authors: Alfisyah Muziibu , Sitohang Osvaldo Zubeldia , Indriyanto Wisnu
Published: February 2024

Detached Plume is the phenomenon of the formation of a cloud of gas/smoke that is interrupted in the main chimney of a cement Plant from the combustion of a kiln containing compounds consisting of Ammonia, Sulfur and Organic Carbon. The Detached Plume that occurred at Plant 9-10 of Indocement-Palimanan was analyzed and controlled so that the SO2 emissions produced could be reduced. This research aims to analyze the effect of Total Organic Carbon (TOC) on clinker production at Plant 9-10, understand the control of Detached Plume and SO2 emissions produced in the main chimney of Plant 9-10, and determine the optimization of the clinker production process at Plant 9-10 by Total Organic Carbon as a variable in Raw Meal. The analysis methods used include monitoring the Detached Plume phenomenon in the Main Chimney, its effect on SO2 Emissions, observing the effect of TOC changes in Raw Material on Clinker production capacity at Plant 9-10. The research results show that the TOC value of Plant 9 is 1.22%, thereby reducing Clinker production capacity to 3466 tpd from the target of 3600 tpd. On the other hand, the TOC value for Plant 10 in the month was 1.00%, thereby reducing Clinker production capacity to 4070 tpd from the target of 4200 tpd. This shows that a significant increase in TOC value in Raw Meal reduces Clinker production capacity. The Detached Plume is also influenced by the ammonia gas content in the main chimney emissions, where the ammonia content > 2 mg/Nm3 increases the visibility of the Detached Plume in the main chimney of Plant 9-10, and the SO2 value
Correlation of public mobility and Covid-19 incidence in Indonesia during six phases of restriction policy implementation
Authors: Sujatmiko Budi , Alhayati Arina Nurhaqiqi , Pratiwi Yuni Susanti , Aryanto Eko Fuji , Halleyana Putri , Indraswari Noormarina
Published: February 2024

Public mobility is considered one of the factors thought to impact the transmission of SARS-CoV2. The Indonesian government has imposed six mobility restriction policies since the beginning of the COVID-19 pandemic to cope this situation, however there has been no comprehensive evaluation of this program. This study aimed to examine the correlation between mobility and the incidence of COVID-19 during the implementation of this policy in Indonesia. Secondary data on public mobility, acquired through the Google Community Mobility Reports, and data on COVID-19 new cases, recorded on the COVID Task Force website, were utilized from 2 March 2020 to 20 July 2021.The analysis in this study was carried out using the Pearson correlation test with an alternative Spearman correlation test. The result reported a positive correlation between COVID-19 cases and mobility in certain places, such as in Grocery Store and Transit Station (r = 0.75; p-value <0.001; r = 0.62 p-value <0.001) while there was negative correlation in residential area (r= - 0.276 p-value < 0.001). Public mobility is found to be correlated with an increase in COVID-19 cases during the six phases of restriction policy implementation. In conclusion, regulating public mobility is important to minimize the risk of COVID-19 transmission.
The occurrence of Antibiotic-Resistant Escherichia coli in the Upper Citarum River and surrounding wastewater effluents
Authors: Kusumah Siska Widya Dewi , Kandio Nadhira , Maghfirah Raihan , Setiyawan Ahmad Soleh , Ariesyady Herto Dwi
Published: February 2024

Wastewater has the potential to introduce antibiotic-resistant bacterial contamination into the adjacent river, posing environmental health risks to surrounding community. However, there is limited data on the bacterial resistance pattern in aquatic environments of developing countries. This study aimed to explore the hazard level of Antibiotic-Resistant Escherichia coli from effluents and river water based on the enumeration and resistance pattern towards thirteen antibiotics of varying potency. Escherichia coli enumeration was performed on samples collected from nine segments of the Upper Citarum River, and the effluents of two hospitals, six farms, five pharmaceutical companies, and two municipal treatment plants. Agar dilution on Chromocult® Coliform Agar ES was utilized to profile antibiotic susceptibility. The results show that Escherichia coli from farm wastewater has the highest average number (43.347 CFU/100mL) and the widest range of antibiotic resistance (up to eight type), followed by Escherichia coli from domestic, hospital and pharmaceutical effluent. Meropenem-resistant Escherichia coli is already detected in all effluent sources. Escherichia coli in the river water was resistant to thirteen types of antibiotics, and the load was increasing downstream. It is important to take immediate and effective measures to address bacterial resistance occurrence in the aquatic environments.
The application of bioassay using Daphnia magna for the evaluation of hospital and pharmaceutical industry wastewater containing Active Pharmaceutical Ingredients (APIs) toxicity
Authors: Tiarina Aisha Maulani , Ariesyady Herto Dwi , Nastiti Anindrya
Published: February 2024

Several groups of Contaminants of Emerging Concern (CECs) including Active Pharmaceutical Ingredients (APIs) can influence ecosystem even at low levels of exposure. The concentration of APIs often belongs to the class of micropollutants, so that toxicity tests should be developed using sensitive test organisms. In this research we developed a potential sensitive Daphnia magna to evaluate the toxicity of APIs-containing wastewater from the total of 7 hospitals and pharmaceutical industries in Greater Bandung, West Java, Indonesia. Physico-chemical parameters that were analyzed including pH, BOD5, COD, TSS, Total N, and Phenol, according to the Ministry of Environment Regulation No. 5/2014. To determine the LC50 values, the Whole Effluent Toxicity (WET) method was applied. The results showed that the maximum concentration of pH, BOD5, COD, TSS, Total N, and Phenol of the pharmaceutical industries WWTP effluents were 7.9, 293 mgL-1, 418 mgL-1, 37 mgL-1, 10.7 mgL-1, and 0.188 mgL-1, respectively. These values have fulfilled the effluent standards. However, based on the acute toxicity testing using WET method, it was found that the minimum LC50 value of those WWTP effluents was 6.51% or equal to the TUa value of 15.35. Based on the TUa toxicity class, this effluent was categorized to be high acute toxic (10 ≤ TUa < 100).
AISI 304 stainless steel milling process state diagnosing
Authors: Polasik Robert , Roszak Mikołaj , Boiko Juliy
Published: February 2024

The article presents the results of works on the analysis of using cutting forces and torque to determine AISI 304 stainless steel milling process state. The research and analyzes were carried out for the determine tool state and the process state itself. The tests were performed using Sandvik milling head, equipped with 345R-1305M-PM 4230 inserts . This study presents and discusses the obtained results determining the resultant value of the minimum and maximum cutting forces and the tool life. The results of observations of the tool's condition were presented.
Parametric modelling of control cable fittings geometric configuration with interpolation of FEA results
Authors: Matiukh Serhii , Dykha Aleksandr , Holenko Kostyantyn , Łukasiewicz Marcin
Published: February 2024

Studying the behavior of control cable fittings (actually a pipe-type part) during radial crimping for fixation on the pipeline is a difficult task since it is necessary to control the presence of obvious plastic deformations: on the one hand, insufficient crimping can cause the fitting to break off from the cable conduit (axial loads over 100 kgf), and on other – the excessive crimping can block the operation of the cable (the core will jam). The selection of the optimal ratio of the fitting diameter and its wall thickness at different load values is the topic of a multi-parameter problem, and one of the ways of solving it will be presented in our research. To evaluate the nonlinear behavior of the Structural Steel NL Ansys material will be used Bilinear Isotropic Hardening stress-strain model with further interpolation of the Tangent Angle Coefficient (TAC) which is suggested as a new calculation parameter of pipe stress estimation.
Formula Student car chassis – research on the torsional stiffness
Authors: Wolska Natalia , Szyca Mikołaj , Estrada Quirino , Castaneda Leonel
Published: February 2024

In the article, the torsional stiffness of a formula student's space frame was analyzed. The article mainly focuses on the comparison of the stiffness between different frame designs, which were used in three consecutive formula student cars designed by the weracing™ team as well as a comparison of the result of two calculation methods. The calculations were made in computer-aided engineering software, i.e. ABAQUS dedicated to analyzing Finite Elements models. The assumption for analysis was to check the rotation of the frame after applying a 5000 Nm load. The torsional load was introduced by first fixed the four rear bulkhead joint and then subsequently applying a force couple to the upper front wishbone mounts. Having a distance between joint from the central line and torque moment, the force for specific nodes can be calculated. The calculation for each model was performed. The obtained differences result from the construction of frames and applied methods of calculations.