51 research outputs found

    Analysis of Annual Rainfall Distribution and Planned Rain Intensity at 11 (Eleven) Rain Post Stations in Serang District

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    This research aimed to find the best rainfall probability model and planned rain intensity using the Mononobe formula for 11 rain stations in Serang Regency. Annual rainfall data is processed and evaluated as secondary data using the rain data consistency test method, the Gumbel probability distribution, the Normal probability distribution, the Log Normal probability distribution, and the Pearson Type III Log probability distribution. The consistency test results reveal that the rainfall data is consistent. The Gumbel probability distribution is used to examine the design rain intensity based on the analysis. This study is intended to guide estimating the design rainfall intensity to develop the design flood discharge and run-off calculations. Suggestions for future research include improving the accuracy of rain data processing and making longer-term data available to provide a more accurate frequency analysi

    Performance Review of Sustainable Urban Drainage System with Lid Concept

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    Purpose: Land conversion reduces infiltration areas and increases runoff that causes flooding and inundation. Efforts to reduce the impact are very important to minimize economic losses. However, large-scale attempts by widening rivers and land acquisition are difficult to implement, especially in urban areas. It requires the management of rainwater runoff at the source. The new paradigm for sustainable urban drainage systems is the LID (low impact development) concept, which approaches hydrology as a framework, considers micromanagement, and controls rainwater at its source.  Design/methodology/approach: It also uses simple non-structural methods to create a multifunctional area. Findings: LID can handle the flood water level and volume as well as the rise and fall of the base flow that will be released to the downstream site and filter waste. Its application consists of several units that depend on local needs, such as porous and semi-permeable pavements, retention and detention reservoirs, wetlands, infiltration trench, ditch, gulley, and well. It also includes a rooftop reservoir, green roofing, rainwater reuse, underground reservoir, grassed strips, and bioswale. Originality/value: This paper is an original work. Paper type: Research pape

    KARAKTERISTIK MEKANIK KOMPOSIT LAMINA SERAT RAMI EPOKSI SEBAGAI BAHAN ALTERNATIF SOKET PROSTESIS

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    Mechanical properties of ramie fiber reinforced epoxy lamina composite for socket prosthesis. This paper presentsan investigation into the application of natural fiber composite especially ramie fiber reinforced epoxy laminacomposite for socket prosthesis. The research focuses on the tensile and shear strength from ramie fiber reinforcedepoxy lamina composite which will be applied as alternative material for socket prosthesis. The research based onAmerican Society for Testing Material (ASTM) standard D 3039/D 3039M for tensile strength and ASTM D 4255/D4255M-83 for shear strength. The ramie fiber applied is a fiber continue 100 % Ne14'S with Epoxy Resin Bakelite EPR174 as matrix and Epoxy Hardener V-140 as hardener. The sample composite test made by hand lay up method.Multiaxial characteristic from ramie fiber reinforced epoxy composite will be compared with ISO standard forplastic/polymer for health application and refers strength of material application at Prosthetics and Orthotics. Theanalysis was completed with the mode of the failure and the failure criterion observation by using Scanning ElectronMicroscope (SEM). Based on results of the research could be concluded that ramie fiber reinforced epoxy compositecould be developed further as the alternative material for socket prosthesis on Vf 40-50%. Results of the research willbe discussed in more detail in this paper.Keywords: mechanical properties, ramie fiber reinforced epoxy lamina composite, socket prosthesi

    Inundation Prediction Model Based On Land Use in Krukut Watershed

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    Purpose: Flooding is a problem in urban areas, particularly in the Krukut watershed. The causative factors are changes in land use, increased land conversion from dry land to watertight built-up land, and reduced water catchment areas. Various efforts to control inundation have been made, but the location of inundation has not been significantly reduced. As a result, a model is required to predict the occurrence of inundation so that it can be anticipated. This study will discuss a mathematical model for predicting inundation in the Krukut Watershed by considering rainfall, land use, and the drainage system. Design/methodology/approach: Researchers gathered inundation data from trusted social media from 2010 to 2020, rainfall data from 2003 to 2018 from the Universitas Indonesia Campus station, and land use data from Citra Landsad in 2019. SPSS was used to analyze the data. Findings: The analysis results show a solid positive correlation with the variable Building Open Area impermeable to inundation. According to the research findings, the inundation area is 0.17 km2. Compared to the EPA SWMM modeling results, the result is 0.21 km2 with a return period of 25 years, with an overall accuracy of 90,91% and a kappa accuracy of 67%. It means that the applied model produces an acceptable level of truth. Paper type: Research pape

    Project delivery systems : The partnering concept in integrated and non-integrated construction projects

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    The project delivery system has a large effect in determining the quality of a project. Strategic plans determined by the owner in the project initiation phase must ensure that project performance indicators in the form of cost and quality as well as time are accomplished. A concept of partnering that is well-managed and planned from the initiation phase will determine the quality of the construction project. Increasing the maturity of partnering is needed in order to achieve better project performance indicators. The concept of partnering in integrated and non-integrated projects has a different pattern. This study intends to discuss the concept of partnering and then recommend several key strategies according to the project life cycle. Research this study is quantitative, analyzing secondary data in the form of weekly meetings and project reports with the comparative method and cause-and-effect analysis. The results show that in the phase above 51% of ongoing projects, there is a significant difference in the pattern of partnering between integrated and non-integrated projects. In order to improve deeper partnering, this research reveals several prerequisites that must be met in order to carry out effective partnering in non-integrated projects. This research may benefit owners, contractors, and stakeholders who want to develop their understanding and knowledge of the concepts of partnering and the maturity of partnering, which will be new strategies for developing and improving project delivery systems. This study focuses on a topic from the Sustainable Development Goals (SDGs), specifically partnership for the goal

    Performance factors for successful business incubators in Indonesian public universities

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    Measuring the performance of business processes is already a main concern for both faculty and enterprise players, since organizations are motivated to reach the productivity stage. Employing a performance achievement framework for the relationship between business incubator success factors will guarantee connection with commercial schemes, which support a high level of performance indicators in successful business incubator models. This research employs a quantitative approach, with the data analyzed using the IBM SPSS version 23 and Smart PLS version 3 statistical software packages. Employing a sample of 95 incubator managers from 19 universities which geographically located in Indonesia, it is shown that the image of business incubator factors has a positive effect on incubator performance. The study investigates the relationship between incubator performance and business incubator success factors in Indonesia. It was found that IT, as part of the business incubatorsā€™ facets/abilities, partially supports their performance; that the entry criteria directly support the performance of the incubators; that mentoring networks also support the performance, with good infrastructure systems as a moderating factor; that funding supports the performance of business incubators, also with good infrastructure systems as a moderating factor; and that university regulations and government support and protection enhance the performance of business incubators, with credits and rewards as a moderating factor. In addition, a variety of indicators from the local context affiliate positively to promote a community that highlighted the incubatorsā€™ strategies.N/

    Application of micromechanical modelling for the evaluation of elastic moduli of hybrid woven juteā€“ramie reinforced unsaturated polyester composites

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    Woven laminated composite has gained researchersā€™ and industryā€™s interest over time due to its impressive mechanical performance compared to unidirectional composites. Nevertheless, the mechanical properties of the woven laminated composite are hard to predict. There are many micromechanical models based on unidirectional composite but limited to the woven laminated composite. The current research work was conducted to evaluate elastic moduli of hybrid juteā€“ramie woven reinforced unsaturated polyester composites using micromechanical effectiveness unidirectional models, such as ROM, IROM, Halpinā€“Tsai, and Hirsch, which are based on stiffness. The hybrid juteā€“ramie laminated composite was fabricated with different layering sizes, and the stacking sequence was completed via hand lay-up with the compression machine. Tensile modulus values for hybrid composites are between those for single jute and single ramie. Obtained p-values less than 0.05 prove the relationship between layering size and tensile modulus. This study showed that several micromechanical models, such as Halpinā€“Tsaiā€™s predicted value of homogenized mechanical properties, were in good agreement with the experimental result. In the case of the hybrid composite, the micromechanical model deviates from the experimental result. Several modifications are required to improve the current existing model. A correlation function was calculated based on the differences between the elastic modulus values determined experimentally and those derived from each micromechanical model calculation

    Influence of dammar gum application on the mechanical properties of pineapple leaf fiber reinforced tapioca biopolymer composites

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    The objective of this work is to investigate the influence of the utilization of dammar gum (DG), which is a biodegradable and renewable binder, on the mechanical properties of short pineapple leaf fiber (PALF) reinforced tapioca biopolymer (TBP). Samples with variable DG concentrations (10%, 20%, 30%, and 40% by weight) and a constant 30% PALF composition were created with varying TBP percentages using an internal mixing process and compression molding. The results showed that PALF-TBP with 10% DG had the highest mechanical properties with tensile, flexural, and impact strength of 19.49ā€‰MPa, 18.53ā€‰MPa and 13.79ā€‰KJ/m2, respectively. Scanning electron microscopy (SEM) images prove the enhanced mechanical characteristics. In addition, Fourier transform infrared spectroscopy (FTIR) analysis showed that the DG improves the matrix and PALF interface. The results show that the utilization of DG significantly enhanced the mechanical characteristics of composites. In addition, it is anticipated that it will be able to create PALF-TBP-DG composites as a potential alternative for conventional polymers in various applications, especially in engineering applications such as automotive and packaging industries. Therefore, it is expected to be capable of contributing to sustainable development goals (SDGs)

    Influence of Post-Heat Treatment on the Characteristics of FeCrBMnSi Coating on Stainless Steel 304 Substrate Prepared by Twin Wire Arc Spray (TWAS) Method at Various Stand-off Distance

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    Twin wire arc spray (TWAS) is a type of thermal spray coating technology that has been extensively researched to improve the service life and overcome wear, cavitation and corrosion in pump impellers. This study aims to investigate the effect of post-heat treatment on the properties of FeCrBMnSi coatings fabricated by the Twin Wire Arc Spray (TWAS) method on 304 stainless steel substrates with varying stand-off distances. NiAl and FeCrBMnSi were employed as bond coats and top coats in this study. The substrate material was sandblasted before the coating process to achieve a surface roughness of 75ā€“100 Āµm. The TAFA 9000 Electrical Wire-Arc Spraying machine's voltage (V), current (A), and compressed air pressure (Bar) were set to 28.4; 150; and 5, respectively. The coating operation was performed at 100, 200, and 300 mm stand-off distances. The specimens were then post-heated for 3 hours at 500Ā°C and 700Ā°C in a Thermolyne F6010 Furnace Chamber. The quality of the coating produced in this study was evaluated using thickness, hardness, wear, bond strength, micrography, and SEM (Scanning Electron Microscope) testing. According to the findings of this study, specimens with a stand-off distance of 100 mm and a post-heat treatment temperature of 700oC produce the best coating qualities when compared to other specimens. This specimen resulted in a percentage of porosity and unmelted material, thickness, hardness, adhesive strength, and total wear rate of 7.1%, 5.53 x 10-1 mm, 1460 HV, 24.86 MPa, and 3.8 x10-4 mm3/s, respectively

    Biodegradation of polylactic acid-based bio composites reinforced with chitosan and essential oils as anti-microbial material for food packaging

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    This study aims to produce and investigate the potential of biodegradable Polylactic Acid (PLA)-based composites mixed with chitosan and Turmeric Essential Oil (TEO) as an anti-microbial biomaterial. PLA has good barrier properties for moisture, so it is suitable for use as a raw material for making packaging and is included in the GRAS (Generally Recognized As Safe). Chitosan is a non-toxic and antibacterial cationic polysaccharide that needs to be improved in its ability to fight microbes. TEO must be added to increase antibacterial properties due to a large number of hydroxyl (-OH) and carbonyl functional groups. The samples were prepared in three different variations: 2 g of chitosan, 0 mL TEO and 0 mL glycerol (Biofilm 1), 3 g of chitosan, 0.3 mL TEO and 0.5 mL of glycerol (Biofilm 2), and 4 g of chitosan, 0.3 of TEO and 0.5 mL of glycerol (Biofilm 3). The final product was characterized by its functional group through Fourier transform infrared (FTIR); the functional groups contained by the addition of TEO are C-H, C=O, O-H, and N-H with the extraction method, and as indicated by the emergence of a wide band at 3503 cmāˆ’1, turmeric essential oil interacts with the polymer matrix by creating intermolecular hydrogen bonds between their terminal hydroxyl group and the carbonyl groups of the ester moieties of both PLA and Chitosan. Thermogravimetric analysis (TGA) of PLA as biofilms, the maximum temperature of a biofilm was observed at 315.74ā—¦ C in the variation of 4 g chitosan, 0.3 mL TEO, and 0.5 mL glycerol (Biofilm 3). Morphological conditions analyzed under scanning electron microscopy (SEM) showed that the addition of TEO inside the chitosan interlayer bound chitosan molecules to produce solid particles. Chitosan and TEO showed increased anti-bacterial activity in the anti-microbial test. Furthermore, after 12 days of exposure to open areas, the biofilms generated were able to resist S. aureus and E. coli bacteria
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