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In developing countries like Indonesia, adding a new unit for hydroprocessing facilities is more efficient than modifying the existing equipment. When the addition occurs, refiners should analyze if the existing hydrogen network can supply enough hydrogen to the new unit before constructing a costly hydrogen plant. Current studies on the hydrogen network have yet to consider pressure drop adequately. Therefore, this paper integrates pressure drop estimation and density prediction into the multi-objective MINLP-based hydrogen network. The multi-objective problem is solved sequentially by adding a minor unit to obtain each configuration's maximum flowrate and total annual cost. The optimal configuration based on the combined objective function is to add 1 PSA and compressor for a hydrogen purity of 0.84 and specified pressure requirements. The pressure drop integration shows an insignificant impact averaging 0.004 m3/s of maximum flowrate difference compared to optimization without pressure drop. • The addition of a new hydroprocessing unit is more efficient than existing refiners. • Multi-objective MINLP-based hydrogen network is used to analyze retrofit options. • The pressure drop integration shows a small impact on the overall. • Network. • The optimal configuration is to add one PSA and one compressor. [ABSTRACT FROM AUTHOR]

• Reducing modifiable risk factors could prevent the onset of cognitive decline. • Physical multimorbidity–cognitive function association was mediated by depression. • Routine screening for depression in multimorbidity patient may delay dementia onset. This paper explores the role of depressive symptoms (mediator/moderator) in the association between physical multimorbidity (exposure) and cognitive function (outcome) among older adults in the three most populous middle-income countries. This study used cross-sectional data from China (2015 China Health and Retirement Longitudinal Study), India (2017/2018 Longitudinal Ageing Study in India), and Indonesia (2014/2015 Indonesian Family Life Survey), with a total sample of 73,199 respondents aged ≥ 45 years. Three domains of cognitive tests were harmonised across surveys, including time orientation, word recall, and numeracy. The four-way decomposition analysis assessed the mediation and interaction effects between exposure, mediator/moderator, and outcome, adjusted for covariates. The mean age of the respondents (in years) was slightly younger in Indonesia (56.0, SD = 8.8) than in China (59.5, SD = 9.3) and India (60.0, SD = 10.5). The proportion of male respondents was 49.3 % in China, 47.3 % in India, and 47.5 % in Indonesia. Respondents in China had the highest mean cognitive function z scores (54.7, SD = 19.9), followed by India (51.1, SD = 20.0) and Indonesia (51.0, SD = 18.4). Physical multimorbidity was associated with lower cognitive function in China and India (p < 0.0001), with 48.4 % and 40.0 % of the association explained by the mediating effect of depressive symptoms ('overall proportion due to mediation'). The association was not found in Indonesia. Cognitive functions were lower among individuals with physical multimorbidity, and depressive symptoms mainly explained the association. Addressing depressive symptoms among persons with physical multimorbidity is likely to have not only an impact on their mental health but could prevent cognitive decline. [ABSTRACT FROM AUTHOR]

As a rapidly developing country, Indonesia faces a challenge in improving air quality that is made more difficult by frequent forest fires linked to deforestation and volcanic eruptions. This paper analyses the link between development and air pollution in 30 Indonesian cities from 2002 to 2019. Air quality is measured using two novel regional air quality indicators (AQIs) for PM 2.5 and PM 10 estimated from weather observations and NASA satellite data on Aerosol Optical Depth (AOD). Results from an Environmental Kuznets Curve (EKC) analysis, based on a dynamic panel data model, show that forest fires and volcanic activity have significantly worsened regional air quality in Indonesia. The model also shows that the EKC hypothesis is rejected for Indonesia as cities have followed a monotonically increasing trend in air pollution with respect to economic growth. An additional 1% of economic growth increased long run pollution as measured by AQI PM 2.5 and PM 10 by 0.35% and 0.46%, and forest fire events by 0.11% and 0.06%. A partial Benefit-Cost Analysis (BCA) of forest fires shows that particulate matter pollution is excessive. Decreasing the frequency of forest fires by 1% would generate a net benefit of between US$17 million to 145 million. The lower estimate of the health benefits exceeds the agricultural benefits of forest fire without accounting for other non-market costs due to forest fires. Our results imply that, as Indonesia grows economically, air quality is likely to continue deteriorating. Further, regions affected by regular volcanic activity and wildfires should apply tighter emission standards to controllable point source emissions from industry and non-point source emissions such as agricultural forest fires. [ABSTRACT FROM AUTHOR]

Several studies have focused on generating seismic vulnerability maps for earthquake-prone areas, particularly in Indonesia. Building typologies are a key factor in determining vulnerability to earthquakes. However, conducting large-scale field surveys to determine the spatial distribution of building typologies in a city is uneconomical. This paper explores the use of a convolutional neural network (CNN) to automatically detect building typologies from diverse regions in Indonesia, utilizing both conventional and automated building image acquisition processes. In this study, datasets from three distinct image acquisition methods are trained with four unique CNN architectures to identify the best-performing model to classify building typologies. The sample size effect on CNN performance is also investigated. The results showed that randomly sampled Google Street View (GSV) images are the most effective dataset for the CNN model, achieving an f1-score of 84.33%. Among the network architectures tested, MobileNet demonstrated superior performance on the majority of evaluated datasets. As the sample size increases by about 350% in the dataset, there is a positive correlation with up to 2.3% f1-score improvement. Using the best-performing CNN model, two building vulnerability models were employed to assess the spatial distribution of building damage in the urban area of Bandung, considering a hypothetical scenario of an M7 earthquake. Incorporating local construction data, one of the generated maps estimated that approximately 55% of buildings in Bandung would experience moderate to severe structural damage. This study showcases the potential of CNN models in automating regional seismic assessments and providing valuable insights for comprehensive seismic mitigation strategies. • A decision tree to label building typology objectively in Indonesia was developed. • CNN model trained with randomly sampled GSV dataset outperforms other models. • The CNN and probability model generated a city-scale building vulnerability map. [ABSTRACT FROM AUTHOR]

• We investigate the use of jurisdictional approaches to promoting sustainable palm oil production. • We theorise the intervention pathways through which jurisdictional approaches promote sustainability. • We analyse the effects of implementation contexts for how jurisdictional interventions are combined and sequenced. • We propose contextually adaptive strategies to improve the impact and resilience of jurisdictional approaches. Voluntary systems of sustainable commodity governance have come under intensified criticism for failing to catalyse transformative change beyond directly regulated supply chains. In response, there has been a surge of efforts to 'scale-up' sustainability impacts through governance interventions at landscape and jurisdictional scales. While these ambitious, scaled-up approaches are attracting significant interest, such approaches demand substantial changes to established repertoires of policy interventions and associated understandings of the pathways through which these contribute to sustainability outcomes. Drawing theoretical insights from scholarship on multi-stakeholder sustainability governance together with findings from a qualitative study of jurisdictional governance experiments in the Indonesian palm oil sector, this paper explores how emerging jurisdictional initiatives are promoting change pathways towards more sustainable commodity production, and how the political, environmental governance and economic contexts in which these interventions are implemented influence these pathways. Analysis shows that by integrating a distinctive mix of market and policy-driven interventions, jurisdictional approaches are contributing to three core pathways of change, centred respectively on network and coalition-building, collaborative governance, and resource mobilisation. However, which of these pathways are most influential, how interventions are sequenced and operationalised, and how the pathways interact in shaping change is highly sensitive to varied subnational implementation contexts, with important implications for the impact and resilience of jurisdictional programs. These findings highlight the need for jurisdictional policy interventions to respond flexibly to contextually-variable configurations of actor interests, coalitions and power relations within contested multi-scalar processes of sustainable commodity governance. [ABSTRACT FROM AUTHOR]

Chloride attack is the main cause of corrosion of reinforced concrete structures subject to marine environment. This paper deals with the assessment of a reinforced concrete jetty structure in Indonesia after 25 years of service life and simultaneously investigate the effect of applying newest Indonesian earthquake code on jetty structural element safety. The work comprises detailed inspection of the structure, on-site and laboratory tests of the structure, and analyses of existing and future structural strength based on the tests data. Current and future strength prediction is performed by assuming average and worst-case scenarios for corrosion. Based on the average-case scenario, the concrete jetty structural elements have no strength reduction up to 2028. By contrast, using the worst-case scenario, the concrete jetty structural elements start experiencing strength reduction in 2003. Applying the 2019 Indonesian earthquake code to analyze the jetty, shows significant reduction of safety factor of steel pipe pile element of the jetty. [ABSTRACT FROM AUTHOR]

The Barito, Pasir, and Tarakan Basins in Kalimantan Island is the most extensive coal-bearing sedimentary basin in Indonesia, mined since 1989. The coal is notable in having high sulfur coal content, exceeding >10% in some cases, contributed by the presence of pyrite. The latter issue contributed to interest in the coal, forming economic mineral deposits hosted by the sedimentary pyrite and organic matter. Novel findings of this research providing valuable information of trace element behavior during the diagenetic conditions. This paper documents the textural and compositional evolution of pyrite-organic matter of coals using coal petrographic, proximate, ultimate, total sulfur content, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), electron probe micro analyser (EPMA), and Raman spectroscopy. Coals from Kalimantan are mainly characterized by medium-high sulfur content (>3%) and the maximum temperatures reached by organic matter during diagenesis are 166 ± 10 °C for the Pasir Basin, 136 ± 11 °C for the Barito Basin, and 132 ± 12 °C for the Tarakan Basin. Pyrite is mainly found as large size framboids (mostly >5 μm), indicating formation in the sedimentary layer with dysoxic bottom water conditions during early–late diagenetic stages. The framboidal pyrite was preferably formed in detrovitrinite and gelovitrinite under topogenous mire conditions, due to the degradation of macerals and biochemical gelification, which provided the organic templates. High concentrations of trace elements (TEs) of framboidal pyrite, such as 1) Cu, Ni, and Co in the Pasir Basin and 2) As in the Barito Basin, likely reflect the local sedimentary provenance and underlying basement rocks. Pyrite texture evolved with increasing diagenetic temperatures from 1) framboidal pyrite, 2) recrystallized framboidal pyrite rims, and 3) anhedral, anhedral-euhedral pyrite transition, and euhedral massive pyrite. This study shows a similar average TE concentrations of various pyrite textures, suggesting that the TEs are not remobilized during the evolution of pyrite at the diagenetic stages. • Medium-high sulfur coals from Indonesia. • Association of pyrite and organic matter. • Textural and compositional evolution of pyrite in coals. • Trace elements of pyrite in coals. [ABSTRACT FROM AUTHOR]

This study aims to demonstrate the comprehensive development of typical meteorological years (TMYs) under relatively limited observational data. The distribution of missing hourly observational data of the 2011–2020 period at all sites was examined. This paper proposes a quality control method for filling the gaps in the missing hourly observational data using bias-corrected ERA5 reanalysis data in the process of developing TMYs. Initially, the temperature bias distribution from −4.5 °C to 2.7 °C was reduced to a range of −0.014 °C to 0.005 °C. The relative humidity bias distribution was −6 % to 10 %, and was reduced to −0.32 % to 0.07 %. The bias distribution of wind speeds ranging from −4 m/s to 2 m/s was reduced to −0.02 m/s to 0.35 m/s. The Sandia method with a modified weighting of Finkelstein-Shaffer (FS) statistics was applied to eight climate elements, namely, global horizontal irradiance, direct normal irradiance, diffuse horizontal irradiance, temperature, precipitation, wind speed, relative humidity, and dew point temperature to generate TMYs at 106 sites across eight climate zones in Indonesia. The verification results showed that the average correlation and RMSE between TMYs and their long-term averages were 0.96 and 75 w/m2 for global horizontal radiation, respectively, while those for temperature were 0.86 and 1.3 °C, respectively. • Quality control was performed on the datasets for the process of developing TMYs. • The ERA5 reanalysis datasets have been improved using a bias correction method. • TMYs have been proposed for 106 sites based on 8 climatic elements. • The climate pattern of each climate zone can be well represented by TMYs. [ABSTRACT FROM AUTHOR]

Palm kernel expeller (PKE), a by-product of the palm oil production process in Indonesia, has evolved into a billion-dollar export 'flex' commodity to feed cows in intensified dairy production in New Zealand. As the PKE trade grew in New Zealand, the dairy industry became a transnational behemoth and a leading global exporter. Through our examination of PKE, an understudied commodity, we reveal the ways that ecological degradation to local, regional, and world-ecologies are exacerbated and intertwined. This paper argues that neoliberalisation of regulatory and trade policy, both within and between the two countries, laid the groundwork for the growth of the ecologically destructive palm oil operations of Indonesia as well as the intensified dairy operations in New Zealand, both of which rely on dispossession of Indigenous lands. Our theorisation builds on the flex commodity literature by analyzing the ways PKE became an 'environmental fix' and part of a transnational waste regime linking two semiperipheral regions. This environmental fix for the dairy industry temporarily limits the negative impacts of climate change induced drought. The world-ecology(ies) of such 'fixes' is becoming increasingly urgent and increasingly tenuous in the face of climate change. [ABSTRACT FROM AUTHOR]