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This research examined the response to increasing temperature of free-living Symbiodinium from three coral host species in the Spermonde archipelago, Indonesia. We cultured free-living Symbiodinium released by corals collected from three different depths (3, 7 and 17 m), representing reef flat, reef edge and reef slope environments. The free-living Symbiodinium were cultured in Conway medium under artificial illumination with 12:12-h dark/light period for 4 weeks. The result showed that free-living Symbiodinium from the three coral hosts and three depths responded significantly to increasing temperature treatments. Symbiodinium from Seriatopora sp had a lower cell abundance than Porites lobata and Porites cylindrica. The highest temperature treatment (34 °C) had a significant effect on cell abundance and growth in Symbiodinium from all species and depths. Symbiodinium from Seriatoporasp coral hosts were the least tolerant to increasing temperature. Symbiodinium from 17 m were the least tolerant to increasing temperature, indicating that corals living in deeper waters may be more vulnerable to increasing temperature than shallow-water corals.

Aim of this study is to investigate the effect of tempering with various heating temperatures (200, 300 and 450°C) and time (2, 4 and 6 hours) on toughness and microstructure of high carbon steel in order to improve its properties. The toughness was measured using the Charpy test and the changes of microstructures were evaluated by Optical Microscope. The analysis was performed for specimens before and after tempering. The results showed the energy of impact and the impact number (toughness) of high carbon steel JIS G4401 were increased by rising tempering temperature. Besides, by addition of the time of tempering, the energy of impact and the toughness were also enlarged. The microstructures of specimens after tempering consisted of ferrite and pearlite phases where the pearlite phase appeared more dominantly during increasing temperature and time of aging.

Islamic finance essentially comprises of Islamic commercial finance (ICF) and Islamic social finance (ISF). This study aims to propose models of integrated Islamic commercial and social finance (IICSF) for Islamic bank in Indonesia using Delphi and Analytic Network Process (ANP) methods. The results propose six IICSF models for Islamic bank, and the IICSF Islamic bank should be prioritized on ICF (0.679) twice more than on ISF (0.321). The best model is Separate Baitul Maal model with integrated activities (0.221), where Islamic bank establishes separate Baitul Maal, as Amil of zakat and Nazir of waqf, to carry out all Islamic social finance activities, including zakat, infaq, waqf and other sadaqa, while the Islamic bank acts as corresponding/receiving bank of the Baitul Maal funds. The close second-best model is Corporate model with integrated activities (0.218), a corporate model, where in the corporate level zakat institution and waqf institution are established to manage Islamic social finance activities, while the Islamic bank will serve as corresponding/receiving bank of the zakat institution and the waqf institution. Even Integrated Baitul Maal model (0.162) is the ideal IICSF model for Islamic bank, it only ranked third, since this model is not yet applicable, since Islamic bank is still not allowed to become Amil of zakat and Nazir of waqf.

In the absence of upper airway patency, supraglottic methods of oxygen delivery become ineffective. We present two semi-elective difficult airway cases where oxygenation via the supraglottic route was deemed impractical due to upper airway obstruction. In order to facilitate safe airway management, apnoeic oxygenation was delivered via a narrow bore transtracheal cannula using a flow-regulated oxygen insufflator. The potential for safely prolonging apnoea time with this technique in both elective and emergency settings is discussed.

•A review of storage technologies.•A review of methods and applications for evaluating storage technologies.•A taxonomy for industry and research.

This is an experiment on the effect of adding various slag concentrations as Portland composite cement (PCC) on the mechanical and chemical properties. Slag waste is lumps of low-quality metal mixed with other materials. The elemental content of Ca in slag has the potential to be used as a substitute for PCC cement in cement mortar products. Slag powder 325 mesh and 400 mesh of 10, 20, 30, and 40% mass concentrations of PCC cement were used in this experiment. The mechanical properties of compressive strength, density, burn shrinkage, porosity and absorption were found to be 4.840 MPa, 2.76 g/cm3, 3.03%, 1.2% and 10.08% respectively, as optimum conditions. Ca elements and CaAl2Si2O8∙4H2O phases that affect mortar adhesion are shown from the results of each XRF and XRD.

Longitudinally welded steel pipe piles are not as commonly used as seamless steel pipe piles in offshore platform. Although longitudinally welded steel pipe piles are considerably cheaper than seamless steel pipe piles, yet many feared that longitudinally welded steel pipe piles are prone to fail because of non-uniformity in the heat affected zone (HAZ), especially when receiving impact loads during the installation process. In this paper, a finite element model is developed to study the deformation and failure of the longitudinal welded piles. Two modelling cases are performed: single and double piles, with two different failure parameters: maximum stress and maximum plastic displacement.

Celecoxib is a non-steroidal, anti-inflammatory drug used in the treatment of pain and inflammation associated with rheumatoid arthritis, and several other inflammatory disorders. It is a class II compound according to the Biopharmaceutics Classification System owing to its low water solubility and high membrane permeability. The objective of this study was to improve the solubility and dissolution rate of celecoxib using solid surfactant technology that might be useful in developing solid dosage forms. Solid surfactant was developed by mixing and grinding together a liquid surfactant (Tween 80) with various inorganic carriers like Fujicalin®(Dibasic Calcium Phosphate Anhydrous), Pineflow®(Porous-structured Maltodextrin), Neusilin®(Magnesium Alumino metasilicate) and Aerosil®(Colloidal Silicon dioxide) in a mortar and pestle in different ratios of liquid surfactant and the carrier to obtain solid surfactants. The celecoxib tablets prepared with solid surfactants were then evaluated for their solubility and dissolution properties. Among the fillers used, Fujicalin showed the highest solubilization capacity for celecoxib. The dissolution behaviors of various tablets prepared with solidified surfactants were compared to those of conventional celecoxib tablets in a simulated gastric fluid. Celecoxib tablets prepared using solidified surfactants showed improved dissolution behaviors when compared to the conventional counterparts. Fujicalin solidified Tween 80 was further analyzed by powder X-ray diffraction analysis, differential scanning calorimetry thermographs and reverse phase high performance liquid chromatography.

The research trend of moving robot mechanism in this decade begins to evolve toward to bio robot mechanism. Bio robot mechanism is objectification of a mechanism that emulates the animal’s gait (bio mimicry). The development such as mechanism has resulted various type of robot that able to move inside the pipeline. The technic of this movement imitates earthworm’s motion, which the traction effect produced from peristaltic movement such as swallowing movement in the digestive organs. Given the way of this movement is similar to peristaltic movement in the digestive organs, so the robot usually called peristaltic robot. Generally, these robots consist of elastic segments that deformed in both longitudinal and transverse direction. Each segment able to deforms alternately to generate wave pattern. These consecutive moving of contract and elongate will produce a movement. This manuscript described design, manufacturing, and laboratory test robot in the pipe tube. The results of early test obtained the value of traction is 142 N and the ability test to climb obtained the maximum tilt angle of pipe about 42° with the slip grade of 37%. This study results peristaltic robot that has capability to crawl inside the pipe tube. It is expected; in the future robot can be used to inspection and maintenance of pipe in oil and gas industry

In this work, a probabilistic fracture mechanics analysis of multiple cracks in a cylindrical pressure vessel was conducted. The analysis was performed to predict service life of a pressure vessel with a certain level of reliability if the vessel has a multiple internal surface cracks that interact each other. The stress intensity factor of multiple cracks configuration was determined from the stress intensity factor of a single surface crack in a plate subjected to uni-axial load and the interaction factor between the cracks. In this work, the Swift’s crack link-up criterion was employed. These parameters together with several other stochastic parameters, i.e. initial crack size, Paris’s crack propagation constants and fracture toughness, were then used to calculate the probability of failure with a certain level of reliability. The failure probability was simulated using guided direct simulation, for cycle-by-cycle crack propagation, to find the expected service life and the mode of failure (leak or break). A case study of a high-pressure vessel having different initial crack sizes have been simulated and the service life with 99,99% reliability were determined.

The use of High-pressure Vessel in eco-friendly Natural Gas Vehicles (NGV) is technologically feasible nowadays. Common applications of High-pressure Vessel are to carry Compressed Natural Gas (CNG), hydrogen for fuel-cell vehicle, and high-compression air in the new air-car technology. High-pressure Vessel is subjected to extreme compression-decompression cycles that could cause fatigue failure. Therefore, vessel shall be inspected regularly to detect if there is crack inside. The objective of this paper is to optimize the inspection interval of CNG Highpressure Vessel by means of Probabilistic Fracture Mechanics Analysis. Vessel is made of highalloy steel and assumed to have distributed elliptical cracks. Three length-to-depth crack ratios (a/c), i.e. 3, 8, and 15, are simulated. Crack is assumed to propagate in fixed ratio. Stress Intensity Factors at each crack tip are calculated by Finite Element Analysis and Crack Closure Technique. Fatigue crack growth is simulated by Cycle-by-Cycle Integration Technique. The Fracture Mechanics Analysis is then expanded to probabilistic analysis by considering stochastic nature of analysis parameters. Probability of failure is computed by Guided Direct Simulation Method using software which is specially written for this project [1]. Based on simulation result, High-pressure Vessel is recommended to be inspected every 3 years.

Cutting tool wear is a major problem in machining processes. It has a great effect on the quality of a workpiece. Thus, monitoring cutting tool wear is very important in order to maintain the workpiece quality as well to reduce production rate and production time. The use of a single sensor in a monitoring system may not be accurate to detect cutting tool wear. In this paper, sensor fusion technology is introduced for monitoring cutting tool wear.

The dynamic nature of marine environment is the major cause of fatigue failures in subsea gas pipeline structures. Since the severest loaded part of piping system is the free span, freespan inspection is performed periodically to ensure that no free span exceeds its critical length. The objective of this paper is to optimize free-span inspection interval by means of probabilistic fracture mechanics analysis. Simulation data is taken from previous work of Tronskar [1]. Stress intensity factors at the crack tip are calculated by crack closure technique. Fatigue crack growth is simulated by cycle-by-cycle integration technique. The fracture mechanics analysis is then expanded to probabilistic analysis to include stochastic input parameters. Probability of failure is computed by modified direct simulation method. Based on the result of direct simulation, the studied pipelines are recommended to be inspected every 3 years to make sure that no free span exceeds 30 m.

We report the first attempts to describe thermophilic bacterial communities in Indonesia's thermal springs using molecular phylogenetic analyses. 16S rRNA genes from laboratory cultures and DNA directly amplified from three hot springs in West Java were sequenced. The 22 sequences obtained were assignable to the taxa Proteobacteria, Bacillusand Flavobacterium, including a number of clades not normally associated with thermophily.

Abstract: The causes and nature of nitrate pollution of wells in a village within Kotagede, a subdistrict of the city of Yogyakarta, Indonesia, were investigated in a detailed hydrological study. Nitrate concentrations in groundwater frequently exceeded the WHO recommended limit of 50 mg L − 1. Groundwater nitrate concentrations were measured over a 19-month period in monitoring wells and in piezometers placed strategically in relation to sewage tanks within the village. Results indicate that the tanks are major sources of nitrate in the groundwater and that the input is markedly dependent on rainfall, resulting in a surge of nitrate into the groundwater at the beginning of each wet season. That the tanks are a major source was confirmed by measuring nitrate in soil cores obtained by augering close to selected tanks. Washrooms, where people wash themselves, are not significant sources of nitrate. Faecal coliform counts in groundwater from a random selection of wells are very high. The results have implications for the siting of wells and toilets within villages in Indonesia.

Fecal specimens from 89 orangutans (36 captive, 34 rehabilitant, and 19 wild) at different locations in Indonesia were examined. Strongyloidesspp, Balantidium coli, and strongylid nematodes were the most common infestations detected. A syngamid nematode, Mammomonogamussp, is reported for the first time in orangutans.

Coronavirus Disease 2019 (COVID-19) has become a pandemic since the beginning of 2020. COVID-19 is also spreading very rapidly in Indonesia and so far, no definitive therapy has been found.

Corrosion is a major cause of the failure of the materials; especially in the cutting tools that mostly use carbon steel ST-37. Painting is performed on ST-37 to reduce or protect metal surface from the destructive effects of weather or the occurrence of corrosion. Besides, it is also applied to improve the esthetical and artistic value of metals. This study was conducted to determine how the influence of the current as well as the time of protection on the thickness of paint by continuous painting method. In this method, the specimens are hanged and hooked at the driving belt that put on the coating tub, and then the specimens are moved along tub during the painting process using the motor. The variables used for protection current are 1A, 2A, and 3A, while the variable times of paintings are 30, 45, and 60 minutes. The thickness of painting is investigated by Optical Microscope. As results, the thickness of the paint layer at a current of 1A, 2A, and 3A and time of 30 minutes are 154.15, 166.6 and 172.8 um. For the coating time of 45 minutes, the thicknesses of the paint layer are 162.4, 181.2, and 191.6 um. Meanwhile, for a coating time of 60 minutes with same above current, the thicknesses of paint are 235.3, 252.05, and 279.1 um. The effective protection layer is found at a protective current of 1A, on 30 minutes of coating time with a thickness of paint layer is 154,15 um.

Online taxi is a transportation mode that mostly grows in urban area. It integrates online technology from cellular phone application to offline activities in its service. This transportation mode is an example of ride sharing concept. This transportation emergence has generated positive and negative impact, where many studies had discussed that. Any kind of transportation mode has an impact to the environment. However the online taxi impact on the environment has rarely been heard. This article aimed to identify the recent studies on the relation of online taxi with green concept. Using Systematic Literature Review and thematic analysis method, the result of research showed that many studies mentioned online taxi is closely related to the green concept. In addition to that, there are still limited number of studies conducted on the policy connecting online taxi to green sustainable energy. Discussion and implication of research was discussed further in the article.

Traditional music in Banyumas especially Calung Banyumasan is very famous for its very distinctive style. But now there is a tendency of quantity and the quality of the music began to decline. Vocational high school of Banyumas is one potential that can be used in this art conservation effort. The purpose of this research is to find the form of preservation of Calung art through education. The result of the research shows that the effort of defence of the art of Calung tradition is part of the effort to preserve the art of tradition and culture of Banyumas in general. The Calung material spread in several subjects, both theoretical and practical manifested in the form of Basic Competence and Basic Material of each subject in the syllabus. All Calung learning materials are classic (Banyumas original style) without influence from other musical styles. Meanwhile, to popularize this type of music, this school performs an off-campus musical performance with a mixed-style, classic and contemporary type. To develop the competence of students and to contribute to the community of artists of this music, the school performs activities Prakerin (Practice industrial activities).

In this study, I compared the physical elements of two Indonesian traditional houses between a Kaili tribe (Central Sulawesi) and a Bugis-Makassar tribe (South Sulawesi). If we viewed of the name, meaning and function from both traditional houses have similarities, namely the Souraja/Saoraja house (House of the King), however, observed more detail the physical elements of architecture also show the differences. The spatial, physical and stylistic systems (N. John Habraken's theory) were applied to analyze their differences and the similarities of the physical elements of architecture on those two traditional houses. The results of the analysis identified that the physical elements of architecture such as the orientation, the function and distribution of rooms (the spatial system), the constructions and materials of floor, wall and roof (the physical system) and the opening types of the door and window as well as ornaments used showed similarities. Meanwhile the physical elements of architecture such as the arrangement of columns, form and spatial pattern as well as the placement of the stairs (the spatial system), the constructions and materials of foundation, column and beam (the physical system) as well as the form of the roof and facade found differences of both traditional houses.