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Wood is biomass made from lignocellulose, the main raw material for pulp production, both species of hardwood and softwood. Utilization of as much wood as possible, including less-known wood species, is widely open because the availability of good quality wood for industry raw materials is increasingly limited. In general, all wood species can be used for paper pulp. But the selection of types of lignocellulosic material with specific properties, such as physical, anatomical and chemical, play an important role in efficiently using wood as raw materials for pulp and paper. This research was carried out to examine wood properties (specific gravity, fiber quality and cellulose content) of four less-known hardwoods from natural tropical rainforest in South Sulawesi province of Indonesia and assessed their potential use for paper pulp. Those hardwood species comprised of cempedak (Artocarpus integer Merr.), jabon merah (Anthocephalus macrophyllus Hav.), saling-saling (Artocarpus teysmanii Miq.) and simpur (Dillenia serrata Thunb.). The specific gravity determined by the weight of oven dried wood and volume of air dried wood where the wood volume be measured by water immersion method, the fiber dimensions measured through maceration preparations which was made using the Franklin procedure, while TAPPI method used for chemical analysis. In condition to paper pulp raw material, the specific gravity (0.40 – 0.69) is categorized as moderate, the fiber quality is classified as good (class II), and cellulose content (40.12% - 52.47%) is categorized as moderate to high for all those less-known hardwoods. All four less-known hardwoods studied potentially use for paper pulp raw materials. But simpur has the most potential due to long fiber and higher specific gravity. [ABSTRACT FROM AUTHOR]

One of the main problems faced in the property management industry especially in Indonesia is limited knowledge or even ignorance of the important role of information technology and information systems in supporting and developing their business. Whereas in a world that is currently heading towards the digital industry and the trend of industry 4.0 which is on the rise, IT and IS components are needed. This paper will explain the important role of IT and IS to help understand their use, and how they can help businesses to grow in the property management industry which is increasingly competitive. The research method used in compiling this paper is in the form of observation of problems in the field. The result of this research is an Information Technology Support Model in the use of information technology to support the property management business. [ABSTRACT FROM AUTHOR]

As a result of the advancement of technology, Indonesia's focus has shifted to the enhancement and simplification of everyday transactions. This is highly common in the widespread use of e-wallets as a payment method for digital transactions involving multiple verification methods, including PIN, Password, Face Recognition and others. This study was conducted by distributing questionnaires to 385 respondents from generation Z in Indonesia who utilized face recognition as a security verification method for digital transactions. The purpose of this paper is to demonstrate the security and efficacy of facial recognition in digital wallet payment verification applications as experienced by users. With the use of the TAM model's analysis, it is proved that all the variables used are significantly related, allowing one to conclude that the safety and efficacy that are possessed are adequate. This paper also supports the growth of trust factors and reasonings for the usage of face recognition in digital transaction self-verification. [ABSTRACT FROM AUTHOR]

According to Indonesia's National Guidelines on Green Buildings (Kemen PUPR No,21,2021) called Penilaian Kinerja Bangunan Gedung Hijau (BGH), green buildings are mandatory for new and existing buildings. As environmental concerns grow, the Government uses these ratings to control energy consumption. A government initiative aims to increase demand for environmentally friendly buildings. This paper evaluates BGH's green building rating system for project certification in two Indonesian cities, Jakarta and Padang Paser Utara. Jakarta is the capital of Indonesia, the largest and one of the most populous urban city in Indonesia. Moreover, the new Indonesia capital city, Nusantara, will be built in Penajam Paser Utara, East Kalimantan. Using the results of this research, recommendations and suggestions can be given related to the design of green buildings both in Jakarta and Penajam Paser Utara. Evaluations will be conducted on simple residential buildings. The results of these studies indicate that designers and architects may have difficulty incorporating this rating systems into their designs. An evaluation of BGH ratings and sustainability analysis can be performed with building information modeling and a conceptual framework is presented toward the end of this paper. A rating system's success depends heavily on discussion among all stakeholders, including architects, engineers, environmentalists, governments, and communities. Indonesian experts in the building sector should take part in and contribute to this project. [ABSTRACT FROM AUTHOR]

This study is based on the problem of microplastics found in water, where plastic packaging is now widely used in food and beverage packaging and raises social concerns about its health effects. The microplastics, small plastic particles with a size of 5 mm or less, found in the body can be toxic, cause hormonal imbalances, heart disease, infertility, and obesity. Research on methods for analyzing microplastics in water is still limited in Indonesia, this study identify and analyze the microplastic content in the drinking water and its saurce in Indonesia using raman spectroscopy method. The analysis of microplastics content was performed on various drinking water samples and their sources. The test included 7 water samples from different brands, water sources and different water bottle industries in Indonesia. Content analysis was performed in three stages, starting with the preparatory stage, the filtration process. The filtration process is performed using filter paper that matches the size of the sample to be inspected. In addition, various particles trapped in the filter paper were analyzed under a microscope to separate the microplastic particles. At last, a raman spectroscopy test was performed to determine the type of microplastics present in the contents of the water sample. Through the analysis and study of the content of various water samples carried out, the analyzed water content found various types of microplastics in the form of fragments, fibers, filaments, and films, most of which were PET (Polyethylene terephthalate). There are also found to be polypropylene and PVC (Polyvinyl chloride). [ABSTRACT FROM AUTHOR]

The steel industries account for 6% of the world's CO2 emissions. The number of emissions will continue to increase as the steel industry in Indonesia grows. Generally, steel production uses blast furnaces which can produce large CO2 emissions. The blast furnace process emissions called blast furnace gas (BFG) contain 20.7% mol of CO2. The high CO2 content also causes the calorific value of the gas to be low, so the gas must be purified to increase its calorific value to be used for power generation. In addition, the steel industry also produces steel slag as waste with a high CaO content (45.2%) but with low economic value. To increase its economic value, CaO content can be used to absorb CO2 from BFG to produce Precipitated Calcium Carbonate (PCC). The use of PCC is very broad for various industrial needs, such as a filler in the paper industry which can increase paper brightness. Therefore, the "Precipitated Calcium Carbonate from Blast Furnace Gas and Steel Slag" plant is expected to be a solution to reduce CO2 emissions from the steel industry. BFG and steel slag as raw materials were obtained from PT. Krakatau Posco. The PCC production process consists of three main stages, namely: (1) Pre-Treatment Steel Slag; (2) Carbonation; and (3) Purification. In the pre-treatment stage, the pH-swing method was used to extract CaO with NH4Cl solvent using pH control. The use of NH4Cl solution is advantageous because it can be recycled. This process obtained a solution of CaCl2 and NH4OH, which was then reacted with CO2 from BFG in a bubble column reactor, resulting in a carbonation process. In the reactor, PCC (CaCO3) and several impurities are formed. The PCC solids formed will then be filtered, dried, and reduced in size so that the moisture content and size are under PCC specifications for the paper industry. Besides producing PCC, purified BFG will be recycled and used as fuel for power generation. The plant location is integrated with PT. Krakatau Posco in the industrial area, Cilegon, Banten, West Java, with a production capacity of 12,750 tons/year. From the results of the economic analysis, with the capital expenditure (capex) of about IDR 337 million and operational expenditure (OPEX) of about IDR 89 million: the payback period is about 6.35 years, and the break-even point (BEP) is 32.38%. [ABSTRACT FROM AUTHOR]

The need for renewable energy is highly increasing worldwide to fulfil energy demand as well as reduce the impact of global warming. Indonesia as the most extensive archipelago face real challenge to power its remote areas with green electricity. This paper assesses economically the idea of hybrid power plant of solar and/or biomass to electrify Indonesian remote areas with green electricity. Furthermore, the carbon credit as an additional income of this project is estimated using CDM methodology. The project is proposed in Sakti, Batukandik, and Batumadeg villages in Nusa Penida Island, Bali; the ER are 7460.57, 2587.10, and 9044.84 tCO2e/year, accordingly. The IRR is analyzed under two scenarios: the initial electricity cost of USD 0.15/kWh and the reduced cost of USD 0.10/kWh including carbon credits and biochar sales. The sensitivity analysis is conducted to observe the effect of most tentative variables towards the IRR. Furthermore, determining the feasibility of this project by analyzing the ERR is assessed to be important, whether it is profitable for the community or not. For the ERR analysis, there are two results calculations. The ERR value with the application of carbon credits shows 32.66%. In comparison, the ERR value without the application of carbon credits shows 28.19%. These values are obtained from several parameter calculations in the ERR analysis in this study. It consists of a consumer surplus, which is computed from the benefits obtained by PLN. Then, the producer surplus and job increases are computed from the benefits obtained by the community if this project is executed. This paper result has essential role in contribution to social, economic, and environmental goal for sustainable development and supporting national economic activities. [ABSTRACT FROM AUTHOR]

COVID 19 disease has spread worldwide, disrupting the economy, society, education, and health. It became crucial to understand the transmission curve and identify the best action in combating this highly transmissible epidemic. Epidemiological parameters of the deterministic Susceptible-Infected-Removed (SIR) model are widely used in explaining the characteristics and behavior of the disease spreading. Disease like COVID-19 is highly influenced by the uncontrolled factors of randomness, hence in this paper, the deterministic susceptible-infected-recovered-death (SIRD) model is extended to the stochastic SIRD (SSIRD) model. SSIRD model takes into consideration the noisy behavior of the process which explains the uncontrolled effects of the COVID-19 outbreak. The epidemiological parameter of the model changes throughout the epidemic due to external factors such as enforcement and public obedience to the control measures as well as the changes in healthcare facilities. These parameters need to be estimated. This paper estimates the epidemiological parameters of the SSIRD model using the Markov Chain Monte Carlo (MCMC) method of the Metropolis Hasting algorithm. The COVID-19 data from Malaysia and Indonesia are used and the dynamical behavior of the COVID-19 outbreak in both countries is simulated. The results show the parameter changing due to the uncontrolled factors influencing the trend of the pandemic curve. [ABSTRACT FROM AUTHOR]

The implementation of Community Activities Restrictions Enforcement (PPKM) during the Covid-19 pandemic reduced activities in the transportation sector. This paper presents the measurement of Carbon Monoxide (CO) concentrations during the PPKM in Makassar City, Indonesia. The samples were collected weekly from August to September 2021 from two traffic-heavy roads using Tedlar bags and a vacuum pump and then analyzed using the Non-Dispersive Infrared method (NDIR). Results showed that the average concentrations of CO on the first street in the morning, midday, and afternoon were 826.63±83.34 µg/m3, 685.65±57.43 µg/m3, 861.6±59.79 µg/m3, respectively; and on the second street were 875.46±77.80 µg/m3, 741.80±62.95 µg/m3, 833.04±44.80 µg/m3, respectively. These CO concentrations measured during the PPKM are lower than those measured before the PPKM on the same sites, reported in another paper. The concentrations are also much lower than those of the Air Quality Standard in Makassar, 30,000 µg/m3. This finding implies that similar policies to reduce traffic and pollution, such as car-free-day, should be enacted to improve air quality. [ABSTRACT FROM AUTHOR]

Urban planners often have a good vision for the urban environment, but that vision is usually limited to visual aesthetics. The sound-based qualitative perspective of the urban environment, which includes sonic and ecological diversity in urban design, is generally ignored. The soundscape approach can be the most effective system for application in urban planning. This paper aims to apply the soundscape approach to urban planning and explore the impact of sound on the formation of urban open spaces through a case study of the Surakarta City parks Indonesia. A mixture of quantitative and qualitative research methods was used. The quantitative method was used to measure background noise using a sound level meter and visualize with a surfer mapping software. The qualitative method was used to observe behavior, the physical environment and perception through interviews. In this context, the paper concludes that the concept of the soundscape is a well-established theme in acoustic environments to identify acoustic data that is compared with the human perception of the environment. Human perceptions of the natural environment and elements of natural sounds, as physical factors, can shape human settlements into a better living environment. [ABSTRACT FROM AUTHOR]