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Synthesis of biodiesel from palm oil with dimethyl carbonate and methanol as reagent variation using KOH and enzyme catalyst

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IOP Conference Series: Earth and Environmental Science 2018年第1期105卷

作者： Setiadi Hamid Fairuz Nawfal Bioprosess Engineering Study Program Department of Chemical Engineering Faculty of Engineering Universitas Indonesia Kampus Baru UI Depok Indonesia

Biodiesel is a methyl ester transesterification process from the result of triglyceride with a methyl reagent source using a catalyst. One of novel reagent used is Dimethyl Carbonate (DMC) which can eliminate the formation of glycerol as the byproduct through the reaction resulting a compound of glycerol dicarbonate. The advantage of this compound has the same physical properties and to be a mixture in one phase liquid product with methyl ester. Lipase is a hydrolase enzyme that can catalyze the formation of fatty acid molecule from the triglyceride containing oil in the reaction of transesterification. The purpose of this research is to produce biodiesel product by observing the formation of one phase mixture of biodiesel product from the palm oilusing methanol and DMC as the reagent, KOH and lipase catalyst andthe variation of molar ratio of the oil. To obtain the best biodiesel quality examined by four characteristics: methyl ester (FAME) content, density, viscosity, and cloud point. The result of this research is that biodiesel can be produced by both reagent, and for biodiesel by DMC there was only one-phase biodiesel formed without impurities shown visually. For catalyst variation, the best biodiesel produced by methanol is biodiesel with KOH catalyst and has 98.2% ester content, 0.858 g/ml density, and 4.58 cSt viscosity. The best biodiesel produced by dimethyl carbonate is biodiesel with KOH catalyst and has 89.0% ester content, 0.883 g/ml density, and 4.91 cSt viscosity.

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Commentaries on Viewpoint: Using V̇o2max as a marker of training status in athletes - can we do better?

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Journal of applied physiology (Bethesda, Md. : 1985) 2022年第1期133卷 148-164页

作者： Pedro L Valenzuela Manuel Mateo-March Xabier Muriel Mikel Zabala Alejandro Lucia David Barranco-Gil Grégoire P Millet Franck Brocherie Johannes Burtscher Martin Burtscher Benjamin J Ryan Rachel A Gioscia-Ryan Stephane Perrey Víctor Rodrigo-Carranza Fernando González-Mohíno José María González-Ravé Jordan Santos-Concejero Benedito S Denadai Camila C Greco Arturo Casado Carl Foster Raffaele Mazzolari Giulia Nicole Baldrighi Elisa Pastorio Davide Malatesta Aurélien Patoz Fabio Borrani Stephen J Ives Justin A DeBlauw Ricardo Dantas de Lucas Fernando Klitzke Borszcz Eduardo Marcel Fernandes Nascimento Luiz Guilherme Antonacci Guglielmo Tiago Turnes Richard T Jaspers Stephan van der Zwaard Romuald Lepers Julien Louis Anderson Meireles Hiago L. R. de Souza Géssyca T de Oliveira Marcelo P dos Santos Rhaí A Arriel Moacir Marocolo B Hunter S Meyler D Muniz-Pumares Renato M Ferreira Abigail S Sogard Stephen J Carter Timothy D Mickleborough Guilherme Pereira Saborosa Raphael Dinalli de Oliveira Freitas Paula Souza Alves dos Santos João Pedro de Souza Ferreira Francisco de Assis Manoel Sandro Fernandes da Silva Christoph Triska Bettina Karsten Dajo Sanders Elliot S Lipksi David J Spindler Matthijs K. C. Hesselink Rodrigo Zacca Márcio Fagundes Goethel David Bruce Pyne Brayden M Wood Peyton E Allen Jaden L Gabelhausen Alexandra M Keller Mast T Lige Alicia S Oumsang Greg L Smart Hunter L Paris Arthur H Dewolf Guillaume Toffoli Borja Martinez-Gonzalez Samuele M Marcora Daniela Terson de Paleville Ricardo J Fernandes Susana M Soares J. Arturo Abraldes Guilherme Matta Arthur Henrique Bossi D G McCarthy W Bostad J Gibala Mary Vagula Grupo de Investigación en Actividad física y Salud (PaHerg) Instituto de Investigación Hospital 12 de Octubre (imas12) Madrid Spain Faculty of Sport Sciences Universidad Europea de Madrid Madrid Spain Sport Science Department. Universidad Miguel Hernández Elche Spain Human Performance and Sports Science Laboratory Faculty of Sport Sciences University of Murcia Murcia Spain Department of Physical Education & Sport Faculty of Sport Sciences University of Granada Granada Spain Institute of Sport Sciences University of Lausanne Lausanne Switzerland Laboratory Sport Expertise and Performance (EA 7370) French Institute of Sport (INSEP) Paris France Department of Sport Science University of Innsbruck Innsbruck Austria Thermal and Mountain Medicine Division US Army Research Institute of Environmental Medicine Natick Massachusetts Department of Anesthesiology University of Michigan Ann Arbor Michigan EuroMov Digital Health in Motion University of Montpellier Montpellier France Sport Training Lab University of Castilla-La Mancha Toledo Spain Facultad de Ciencias de la Vida y de la Naturaleza Universidad Nebrija Madrid Spain Department of Physical Education and Sport University of the Basque Country UPV/EHU Vitoria-Gasteiz Spain Human Performance Laboratory São Paulo State University Rio Claro Brazil Center for Sport Studies Rey Juan Carlos University Madrid Spain University of Wisconsin-La Crosse La Crosse Wisconsin Department of Physical Education and Sport University of the Basque Country (UPV/EHU) Vitoria-Gasteiz Spain Department of Molecular Medicine University of Pavia Pavia Italy Department of Brain and Behavioural Sciences − Medical and Genomic Statistics Unit University of Pavia Pavia Italy Department of Biomedical Sciences for Health University of Milan Milan Italy Institute of Sport Sciences of University of Lausanne (ISSUL) University of Lausanne Lausanne Switzerland Health and Human Physiological Sciences Skidmore College Saratoga Springs New

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Increasing accuracy of classification physical activity based on smartphone using ensemble logistic regression with boosting method

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Journal of Physics: Conference Series 2019年第4期1341卷

作者： A Lawi F Aziz S L Wungo Department of Computer Science Universitas Hasanuddin Makassar Indonesia. 90245 Faculty of Mathematics and Natural Sciences Universitas Pancasakti Makassar Indonesia. 90132 Program Study Informatics Engineering STMIK Kreatindo Monokwari Indonesia. 98300

At present, the smartphone is equipped with several sensors such as Accelerometer, Gravity sensor, and Gyroscope which can be used to recognize human physical activities such as walking upstair and walking downstairs etc. Machine learning is needed to group data and get information. Statistical methods have poor performance in classifying because procedures must be met. To overcome this, an ensemble technique was used. This study proposes the application of the gradientboost ensemble method to classify walking upstair and walking downstairs. The *** system is designed for data retrieval using a smartphone. Then, the dataset will be partitioned into 70% training data and 30% test data. The results show that the performance of the ensemble boosting method produces 81.82% accuracy, 86.11% sensitivity and 77.50% specificity.

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The difference of delay time in monitoring system of facial acupressure learning media using bluetooth, wireless and ethernet

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AIP Conference Proceedings 2018年第1期1941卷

作者： Eny Widhia Agustin Arimaz Hangga Muhammad Iqbal Fahrian Anis Fikri Azhari Beauty Education Study Program Faculty of Engineering Universitas Negeri Semarang Semarang Indonesia Electrical Engineering Department Faculty of Engineering Universitas Negeri Semarang Indonesia

The implementation of monitoring system in the facial acupressure learning media could increase the students’ proficiency. However the common learning media still has not implemented a monitoring system in their learning process. This research was conducted to implement monitoring system in the mannequin head prototype as a learning media of facial acupressure using Bluetooth, wireless and Ethernet. The results of the implementation of monitoring system in the prototype showed that there were differences in the delay time between Bluetooth and wireless or Ethernet. The results data showed no difference in the average delay time between the use of Bluetooth with wireless and the use of Bluetooth with Ethernet in monitoring system of facial acupressure learning media. From all the facial acupressure points, the forehead facial acupressure point has the longest delay time of 11.93 seconds. The average delay time in all 3 class rooms was 1.96 seconds therefore the use of Bluetooth, wireless and Ethernet is highly recommended in the monitoring system of facial acupressure.

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Design of Single Stage Axial Turbine with Constant Nozzle Angle Blading for Small Turbojet

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Journal of Physics: Conference Series 2018年第1期1005卷

作者： F Putra Adnan Firman Hartono Aeronautics and Astronautics Study Program Faculty of Mechanical and Aerospace Engineering Institut Teknologi Bandung

In this paper, an aerodynamic design of a single stage gas generator axial turbine for small turbojet engine is explained. As per design requirement, the turbine should be able to deliver power output of 155 kW at 0.8139 kg/s gas mass flow, inlet total temperature of 1200 K and inlet total pressure of 335330 Pa. The design phase consist of several steps, i.e.: determination of velocity triangles in 2D plane, 2D blading design and 3D flow analysis at design point using Computational Fluid Dynamics method. In the determination of velocity triangles, two conditions are applied: zero inlet swirl (i.e. the gas flow enter the turbine at axial direction) and constant nozzle angle design (i.e. the inlet and outlet angle of the nozzle blade are constant from root to tip). The 2D approach in cascade plane is used to specify airfoil type at root, mean and tip of the blade based on inlet and outlet flow conditions. The 3D approach is done by simulating the turbine in full configuration to evaluate the overall performance of the turbine. The observed parameters including axial gap, stagger angle, and tip clearance affect its output power. Based on analysis results, axial gap and stagger angle are positively correlated with output power up to a certain point at which the power decreases. Tip clearance, however, gives inversely correlation with output power.

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Conservation of batik: Conseptual framework of design and process development

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AIP Conference Proceedings 2018年第1期1941卷

作者： Rodia Syamwil Fashion Education Study Program Engineering Faculty Universitas Negeri Semarang Semarang Indonesia

Development of Conservation Batik concept becomes critical due to the recessive of traditional batik as the intangible cultural heritage of humanity. The existence of printed batik, polluting process, and new stream design becomes the consequences of batik industry transformation to creative industry. Conservation Batik was proposed to answer all the threats to traditional batik, in the aspect of technique, process, and motif. However, creativities are also critical to meet consumer satisfaction. Research and development was conducted, start with the initial research in formulating the concept, and exploration of ideas to develop the designs of conservation motifs. In development steps, cyclical process to complete motif with high preferences, in the aspect of aesthetics, productivity, and efficiency. Data were collected through bibliography, documentation, observation, and interview, and analyzed in qualitative methods. The concept of Conservation Batik adopted from the principles of Universitas Negeri Semarang (UNNES) vision, as well as theoretical analyses, and expert judgment. Conservation Batik are assessed from three aspect, design, process, and consumer preferences. Conservation means the effort of safeguarding, promoting, maintaining, and preserving. Concervation Batik concept could be interpreted as batik with: (1) traditional values and authenticity; (2) the values of philosophycal meanings; (3) eco-friendly process with minimum waste; (4) conservation as idea resources of design; and (5) raising up of classic motifs.

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Utilization of lignin as natural antioxidant for biodiesel

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AIP Conference Proceedings 2018年第1期2024卷

作者： Andre Fahriz Perdana Harahap Misri Gozan Bioprocess Study Program Chemical Engineering Department Faculty of Engineering Universitas Indonesia Kampus UI Depok 16424 Indonesia

As phenolic polymer compound, the hydroxyphenolic groups in lignin enable it to act as antioxidant. In this study, organosolv and commercial lignin were tested for their activity as antioxidant in biodiesel. Organosolv lignin was obtained by first performing pretreatment of Oil Palm Empty Fruit Bunch (OPEFB) by organosolv method at 170 °C for 2.5 hours followed with isolation by use of H2SO4 20%. The organosolv and commercial lignin were added separately to biodiesel with concentration variation of 500, 1000, and 1500 ppm. Synthetic antioxidant butylated hydroxytoluene (BHT) was used as positive control in this study. Biodiesel oxidation stability test was performed by Rancimat method. Antioxidant activity tests were done by determining the acid value, peroxide value, and kinematic viscosity of biodiesel each week for 4 weeks. The yield and lignin content of organosolv lignin obtained from this study were 13,7% and 64.5% respectively. Hydroxyphenolic content of organosolv lignin by means of spectroscopy method showed value of 6.8%. Addition of organosolv lignin, commercial lignin, or BHT showed ability to inhibit the oxidation rate of biodiesel with the sequence of antioxidant activity from the largest to the smallest are successively BHT, commercial lignin, and organosolv lignin. Rancimat test showed that 1500 ppm organosolv lignin resulted 4.2 minutes biodiesel induction time which equals the result of 1000 ppm commercial lignin as well as 500 ppm BHT. This study reveals that organosolv lignin from OPEFB and commercial lignin have future potential to be utilized as natural antioxidant for biodiesel.

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Analysis of piperine content in cabe jawa extracts (Piper retrofractum Vahl) using UV spectrophotometry and HPLC

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IOP Conference Series: Materials Science and engineering 2019年第1期509卷

作者： Bambang Cahyono Eli Fatihatul Hasanah Judiono Meiny Suzery Widayat Organic Chemistry Laboratory Department of Chemistry Faculty of Science and Mathematics University of Diponegoro Semarang Indonesia Center for Research of Indonesian Herbal and Herbs Diponegoro University Semarang Indonesia Diploma III Study Program of Nutrition Bandung Polytechnic of Health Jl Babakan Loa Village Pasir Kaliki Cimahi Indonesia Department of Chemical Engineering Faculty of Engineering Diponegoro University Tembalang Semarang Indonesia

Cabe Jawa (Piper retrofractum Vahl) is an important commodity for herbal industries in Indonesia. One of the bioactive compounds in this herb is piperine. In this study, concentration of piperine in Cabe Jawa was analysed using HPLC and UV spectrophotometry methods. Cabe Jawa samples were prepared using two different methods. The first sample (S1) was dried from fresh Piper retrofractum, while the second sample (S2) was dried from boiled Piper retrofractum. Both samples were extracted using Soxhlet, followed by solvent evaporation to obtain the concentrated extract. Piperine concentration was measured using UV spectrophotometry and HPLC via internal standard method. The yields of extract of S1 and S2 were 23.0% and 22.1%, respectively. Piperine UV spectrophotometry standard curve equation was y = 0.1107*(X)-0.1578, R2 = 0.9999, whereas HPLC standard curve equation was y = 105916*(X) + 28100.9, R2 = 0.9978. Piperine concentration in S1 and S2 extracts quantified using UV spectrophotometry were 19.0% and 18.1%., respectively. The values for S were much higher compared to values obtained by HPLC, which were 6.8% (S1) and 7.3% (S2). Therefore, the use of UV spectrophotometry for analysis of piperine is not recommended due to the interference of other compounds, which are absorbed at the same wavelength.

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Response of Gravity, Magnetic, and Geoelectrical Resistivity Methods on Ngeni Southern Blitar Mineralization Zone

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Journal of Physics: Conference Series 2018年第1期979卷

作者： Sunaryo Geophysical Engineering Program Study Physics Department Sciences Faculty University of Brawijaya Malang Indonesia

The research with entitle response of gravity, magnetic, and geoelectrical resistivity methods on Ngeni Southern Blitar mineralization zone has been done. This study aims to find the response of several geophysical methods of gravity, magnetic, and geoelectrical resistivity in an integrated manner. Gravity data acquisition was acquired 224 data which covers the whole region of Blitar district by using Gravity Meter La Coste & Romberg Model 'G', and magnetic data acquisition were acquired 195 data which covers the southern Blitar district only by using Proton Precession Magnetometer G-856. Meanwhile geoelectrical resistivity data only done in Ngeni village which is the location of phyropilite mining with the composition content of Fe, Si, Ca, S, Cu, and Mn by using ABEM Terrameter SAS 300C. Gravity data processing was performed to obtain the Bouguer anomaly value, which included unit conversion, tidal correction, drift correction, correction of tie point, base station correction, free air correction, and Bouguer correction. Magnetic data processing has been done by some corrections i.e daily, drift, and IGRF(International Geomagnetic Refference Field) to obtain the total magnetic anomaly. From gravity data processing has been obtained the simple Bouguer anomaly value in range from -10mGal until 115mGal. From this data processing has been obtained the total magnetic anomaly value in range from -650nT until 800nT. Meanwhile from geoelectrical resistivity 3.03Ωm until 11249.91 Ωm. There is a correlation between gravity anomaly, magnetic anomaly, and geoelectrical resistivity anomaly that are associated with deep anomaly, middle anomaly, and shallow anomaly.

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The dynamic model of paddy field conversion control in Citarum watershed

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IOP Conference Series: Earth and Environmental Science 2019年第1期399卷

作者： I Firmansyah Widiatmaka B Pramudya S Budiharsono Study Program of Natural Resources and Environmental Management IPB University Department of Soil Science and Land Resources Faculty of Agriculture IPB University Department of Mechanical Engineering and Biosystem Faculty of Agriculture Technology IPB University Technical Advisor Ministry of National Development Planning/National Development Planning Agency (BAPPENAS)

The rate of population growth and the increase in food needs for consumption have made the need for paddy fields higher. On the other hand, the pressure on paddy fields is quite intense so that the conversion of paddy fields is quite challenging to be controlled. Moreover, the concerns about food security and food sovereignty have become critical issues. The high demand for land utilization has caused pressure on paddy fields in the Citarum watershed. The objective of this study is to build a model for maintaining paddy fields in the Citarum watershed. The study was conducted from June to September 2015. The method of this research is a modelling using system dynamics approach by simulating time series data. From the simulation, it can be concluded that the rate of conversion of paddy fields will still be high if there is no specific policy in its protection. This fact can be seen from various scenario conditions, either in existing circumstances, in the optimistic scenario, as well as in a moderate scenario. The strategy that can be done is that paddy fields should be specially protected or owned by the government to minimize the rate of conversion.

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