Mudianta I.W.,University of Queensland |
Mudianta I.W.,Ganesha University of Education |
Skinner-Adams T.,Griffith University |
Skinner-Adams T.,Queensland Institute of Medical Research |
And 6 more authors.
Journal of Natural Products | Year: 2012
Twenty-one new psammaplysin derivatives (4-24) exhibiting a variety of side chains, as well as six previously known psammaplysins, were identified from the Indonesian marine sponge Aplysinella strongylata. The double bond on the side chain of the fatty acid-containing psammaplysins was located by GC-MS analysis of the fatty acid methyl esters and their pyrrolidide derivatives. HPLC and Mosher ester studies confirmed that the isolated metabolites possessing a 19-OH substituent were mixtures of diastereomers. Selected compounds (4, 5, 7, 8, 12, 18, and 22) were screened for in vitro activity against chloroquine-sensitive (3D7) P. falciparum malaria parasites. Of the new psammaplysins, 19-hydroxypsammaplysin E (4) showed the best antimalarial activity, with an IC50 value of 6.4 μM. © 2012 The American Chemical Society and American Society of Pharmacognosy.
Antara I.N.G.,Udayana University |
Made K.G.,Udayana University |
Ketut G.,Ganesha University of Education
Key Engineering Materials | Year: 2016
The development of the automotive industry brings impact of increasing use of aluminum for vehicle components that will ultimately produce more aluminum waste. If it is not addressed properly, it will be a serious problem for the environment. One of the solutions is to recycle the waste of drum brake to be a raw material for motorcycle accessories brake handle. The process of making motorcycle brake handle using the sand casting method can be done by varying the temperatures of casting molten metal which are at temperatures of 650°C, 700°C and 750°C. Furthermore, the testing of the mechanical properties and microstructure of the resulted product is done. The result shows that motorcycle brake handle required high impact strength in which the highest impact strength was 0.011 Nm/mm2 that was obtained when temperature of casting was 700°C. © 2016 Trans Tech Publications, Switzerland.
Ruliati L.P.,Udayana University |
Adiputra N.,Udayana University |
Sutjana I.D.P.,Udayana University |
Sutajaya I.M.,Ganesha University of Education
Proceedings - Joint International Conference on Electric Vehicular Technology and Industrial, Mechanical, Electrical and Chemical Engineering, ICEVT 2015 and IMECE 2015 | Year: 2015
One of the industries that support the fulfillment of food self-sufficiency is the rice milling industry. Rice milling activity cannot be separated from the working conditions. The working conditions in the rice mill at general pay less attention to the design aspects of ergonomics, occupational health and safety where employees work in standing, bent, and head down position, also lifting weights constantly. It causes fatigue and musculoskeletal disorders increases. This study aims to determine the improvement of working conditions may reduce fatigue and musculoskeletal disorders. The research uses experimental design Randomized Pretest and Posttest Control Group Design. The subject of research in the form of 30 male workers in the rice mill with an age range 16 until 56 years, divided into 15 subjects in the control group and 20 in the treatment group. The results showed that the post-test average the fatigue, there are results of 76.40 more less 13.50 in the control group and 55.53 more less 9.51 in the treatment group. Significance analysis showed that after two groups grind the rice, the fatigue average significantly different p less than 0.005. The amount of reduction in fatigue between the two groups was 27.31 percent. In the musculoskeletal disorders after the posttest showed that the mean score of musculoskeletal disorders in the control group was 77.33 more less 12.31 and the treatment group was 49.53 more less 8.18. Analysis of significance to the Independent Samples T Test after posttest showed that both groups average musculoskeletal disorders are different significantly, p less than 0.05. The amount of reduction in musculoskeletal disorders between the control group and the treatment group after the activity amounted to 35.95 percent. From this study we can conclude that the improvement of working conditions with the ergonomic approach may reduce the fatigue by 27.31 percent and musculoskeletal disorders by 35.95 percent. © 2015 IEEE.
Nyoman Sukajaya I.,Ganesha University of Education |
Ketut Eddy Purnama I.,Sepuluh Nopember Institute of Technology |
Purnomo M.H.,Sepuluh Nopember Institute of Technology
International Journal of Emerging Technologies in Learning | Year: 2015
Lately, personalized learning approach attracted the attention of so many researchers due to its capacity to improve the quality of educational system. This approach provides opportunities to maximize the potential of all students based on their profile. This indicates the necessity of grouping learners' profiles appropriately in order to optimize contribution of personalized learning approach in achieving learning objective. The problems occurred when classifying learners' profile especially when dealing with large number of learners, restricted time to classify, and requirement of authentic data. To solve the problem, we proposed the implementation of Bloom's taxonomy-based serious game as an assessment tool replacing paper-based tool for the gameplay data collection. Three different methods namely: BN, NB, and J48 were implemented to obtain the highest accuracy of classification. Our study finds that the NB classifier gives the highest percentage accuracy that is 92.31%. This classifier has the similar accuracy with BN but with lower error rate. In view of the strength of agreement, the result is categorized Very Good (κ = 0.85).
Siswanto E.,Bandung Institute of Technology |
Khodra M.L.,Bandung Institute of Technology |
Erawati Dewi L.J.,Ganesha University of Education
Proceedings - 2014 International Conference on Advanced Informatics: Concept, Theory and Application, ICAICTA 2014 | Year: 2014
Numerous studies have been conducted to explore the social network of Twitter; some have been conducted to predict the interest or the topic of the user's tweet. In this study, we investigate the best classification model for determining the user's interest based on the bio and a collection of tweets. We use the supervised learning-based classification with the lexical features. Two approaches were proposed; they are the classification that was made based on the user's tweet using multilabel classification method and the classification that was made based on specific accounts. From the result of experimental result, it could be concluded that the employment of the classification using specific accounts approach led to better accuracy. © 2014 IEEE.
Mudianta I.W.,University of Queensland |
Mudianta I.W.,Ganesha University of Education |
Katavic P.L.,University of Queensland |
Lambert L.K.,University of Queensland |
And 5 more authors.
Tetrahedron | Year: 2010
Chemical analysis of an Indonesian sponge sample has provided three new 3-alkylpiperidine alkaloids, tetradehydrohaliclonacyclamine A, its mono-N-oxide derivative, and a 2-epi isomer. The absolute structure of tetradehydrohaliclonacyclamine A has been established by X-ray crystallography from anomalous dispersion effects using Cu radiation, which determined that the absolute configuration is 2S, 3S, 7S, 9S while an HPLC study revealed that the alkaloid is enantiomerically pure. © 2010 Elsevier Ltd. All rights reserved.
Seidel M.,University of Oldenburg |
Beck M.,University of Oldenburg |
Riedel T.,University of Oldenburg |
Waska H.,University of Oldenburg |
And 6 more authors.
Geochimica et Cosmochimica Acta | Year: 2014
Seawater circulation in permeable coastal sediments is driven by tidal changes in hydraulic gradients. The resulting submarine groundwater discharge is a source of nutrients and dissolved organic matter (DOM) to the water column. Yet, little is known about the cycling of DOM within tidal sediments, because the molecular DOM characterization remains analytically challenging. One technique that can dissect the multitude of molecules in DOM is ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). To aim at a high resolution DOM analysis we study the seasonal turnover and marine and terrestrial sources of DOM in an intertidal creek bank of the southern North Sea down to 3m depth and link the biogeochemical processes to FT-ICR-MS data and the analyses of inorganic porewater chemistry, δ13C of solid-phase extracted dissolved organic carbon (SPE-DOC), dissolved black carbon (DBC) and dissolved carbohydrates (DCHO). Increasing concentrations of dissolved Fe, Mn, P, total alkalinity, dissolved nitrogen, DOC and a concomitant decrease of sulfate along the seawater circulation path from the upper tidal flat to the tidal flat margin indicate continuous microbial activity. The relative increase of Si concentrations, unsaturated aliphatics, peptide molecular formulae and isotopically more 13C-enriched SPE-DOC towards the tidal flat margin suggests that remineralization processes mobilize DOM from buried algal (diatoms) and microbial biomass. Porewater in sediments <100cm depth contains 13C-depleted SPE-DOC and highly unsaturated compounds which are probably derived from eroded peats, suggesting rapid removal of bioavailable marine DOM such as DCHO from the water column and selective enrichment of terrestrial DOM. DBC concentrations are highest in the discharging porewater close to the tidal creek suggesting that the intertidal flat is an important DBC source to the coastal ocean. Porewater DOM accumulating at the low water line is enriched in N and S. We hypothesize that this is partly due to DOM reacting with dissolved sulfide and ammonium which may increase the refractory character of the DOM, hence making it less bioavailable for in situ active microbes. © 2014 Elsevier Ltd.
Dantes K.R.,Ganesha University of Education
International Journal of Applied Engineering Research | Year: 2015
The aims of this reseach is to obtained push metal v belt life time developed using austenitic AISI 205 material for Continously Variable Transmission (CVT). By using analytical methods, the reseach focused on tensile stress of steel ring and shear stress of pulley element contact.Thermal stress and bending stress occured on push metal v belt components. The result showed at ratio > 1 have 3,9106x105 cycle. Fo ratio =1 and ratio <1, the life time were 3,6522 x 105 cycle and 3,1282 x 105 cycle. © Research India Publications.
Darmawiguna I.G.M.,Ganesha University of Education |
Sunarya I.M.G.,Ganesha University of Education |
Kesiman M.W.A.,Ganesha University of Education |
Arthana K.R.,Ganesha University of Education |
Crisnapati P.N.,Ganesha University of Education
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2015
The Balinese people often tell their stories through dance, drama, textile designs, puppetry and music. Many stories are important as they teach children ideas about their land, traditions and customs. This project aims at the development of augmented reality story book that focusing on Balinese miths, and legends. Augmented reality is a live direct or indirect view of a physical, real-world environment whose elements are augmented by computer-generated sensory inputs. The application for augmented reality story book is developed in android mobile devices and was developed by using Unity3D with additional Vuforia libraries. The idea of the project is to make a story telling book with augmented reality technology. The book contains the image target as marker to display the objects from augmented reality application. When the application is pointed to the marker of book, the animated 3D scenes will show up combining with the narration of story and music. © Springer International Publishing Switzerland 2015.
Gunamantha M.,Ganesha University of Education |
Sarto,Gadjah Mada University
Renewable Energy | Year: 2012
Various methods of solid waste treatment are available. However, due to heterogeneity characteristic of solid waste, determined the best means to manage solid waste in environmental view of point is not straightforward. In this case, solid waste management scenarios and an environmental analysis tool are required. This study compared various energetic valorization options with each other using the simplified Life Cycle Assessment (LCA) methodology. These scenarios were landfilling without energy recovery as a representative of existing solid waste management, landfilling with energy recovery, combination of incineration and anaerobic digestion, combination of gasification and anaerobic digestion, direct incineration, and direct gasification. A case study area in a typical KARTAMANTUL (acronym of three cities: Yogyakarta, Sleman, Bantul) intercity region in province of Yogyakarta, Indonesia. One ton of solid waste treated was defined as the functional unit of the systems studied. The Life Cycle Inventory (LCI) analysis was done by including field and laboratory survey to characterize solid waste in area study and using emission factors which were adopted from literature to estimate environmental burdens for each scenario. Inventory's result was classified into impact categories, i.e. global warming, acidification, eutrophication, and photochemical oxidant formation. The indicators of categories were quantified by using the equivalence factors of relevant emissions to determine the environmental performance of each scenario. The study shown that in most of the impact categories (except acidification), a scenario with direct gasification indicated the best environmental profile. A sensitivity analysis was also conducted to examine change in outcomes for a variety of organic biowaste inputs, but had no significant effect on the overall result. © 2011 Elsevier Ltd.