52 research outputs found
Development and application of generalized MUSTA schemes
No full textNumerical methods for solving non-linear systems of hyperbolic conservation laws via finite volume methods or discontinuous Galerkin finite element methods require, as the building block, a monotone numerical flux. The simplest approach for providing a monotone numerical utilizes a symmetric stencil and does not explicitly make use of wave propagation information, giving rise to centred or symmetric schemes. A more refined approach utilizes wave propagation information through the exact or approximate solution of the Riemann problem, giving rise to Godunov methods. Conventional approximate Riemann solvers are usually complex and are not available for many systems of practical interest, such as for models for compressible multi-phase flows. It is thus desirable to construct a numerical flux that emulates the best flux available (upwind) with the simplicity and generality of symmetric schemes. Here we build upon MUSTA approach [2,3], which leads to schemes that have the simplicity and generality of symmetric schemes and the accuracy of upwind schemes. First we present a new flux that is an average of symmetric fluxes and which reproduces the Godunov upwind scheme for the model hyperbolic equation. For non-linear systems it is found that this flux gives superior results to those of the whole family of incomplete Riemann solvers that do not explicitly account for linearly degenerate fields. Then we incorporate this flux into the MUSTA multi-staging approach, as predictor and corrector. It is found that the resulting MUSTA schemes reproduce the Godunov upwind scheme for the model hyperbolic equation for any number of stages, including multiple space dimensions. They are linearly stable in two and three space dimensions and the stability region is identical to that of the Godunov upwind method. For non-linear systems the MUSTA scheme with one or two stages gives results that are indistinguishable from those of Riemann solvers, such as the exact Riemann solver or Roe approximate Riemann solver. Finally, we assess the schemes on carefully chosen test problems for the one-dimensional equations of magneto hydrodynamics and nonlinear elasticity. High-order examples are provided for the multidimensional Euler equations in the framework of finite-volume WENO schemes [1]. The results illustrate the accuracy and efficiency of new methods combined with the ease of coding
Functional Cramér–Rao bounds and Stein estimators in Sobolev spaces, for Brownian motion and Cox processes
No full textWe investigate the problems of drift estimation for a shifted Brownian motion and intensity estimation for a Cox process on a finite interval [0,T], when the risk is given by the energy functional associated to some fractional Sobolev space H01⊂Wα,2⊂L2. In both situations, Cramér–Rao lower bounds are obtained, entailing in particular that no unbiased estimators (not necessarily adapted) with finite risk in H01 exist. By Malliavin calculus techniques, we also study super-efficient Stein type estimators (in the Gaussian case)
Preparasi dan Karakterisasi Katalis CoMo/H-Zeolit Y
No full textPreparation and characterization of catalyst CoMo/H-zeolite Y has
been done. Catalyst was prepared from NH4Y-zeolite then heated 115oC for 1 h
to eliminate water then calcined at 550oC for 2 h to evaporate ammonia,
produced HY-zeolite (HYZ) sample. Impregnation of CoMo metals on the HYZ
sample was done by co-impregnation method, where the HYZ (10 g) was mixed
with (NH4)6MO7O24.4H2O in 24 mL aquabidest and 3 mL of ammonia then
stirred of 60oC for 2 h. This mixture was then mixed with Co(NO3)2.6H2O in 24
mL aquabidest and 3 mL of ammonia then stirred of 60oC for 2 h. The resulting
sample was filtered and dried. The dried sample was then calcined under N2
stream at temperature of 550oC for 2 h, followed by oxidized with O2 then
reduced with H2 stream at temperature 400oC for 2 h, respectively produced
CoMo/HY catalyst. Characterization of the catalyst included analysis of NH3
groups was done with by infra red spectrofotometry (IR), the crystallinity with Xray
diffraction (XRD) and the acidity was calculated with NH3 absorption by
gravimetry method, metal content on the catalyst was determined by atomic
absorption spectroscopy (AAS). FTIR result of CoMo/HY catalyst showed that
disappeared ammonia was after heating. The XRD date indicated the increase of
catalyst crystallinity as the following: NH4Y< died NH4Y < HY< CoMo/HY.
CoMo/HY catalyst has average acidity = 6,87 mmol/g where as the HY has
average acidity = 7,66 mmol/g. The metal content in the HY was 8023 and 7681
ppm, for Co and Mo respectively
HIDRODESULFURISASI TIOFEN MENGGUNAKAN KATALIS CoMo/H-ZEOLIT Y
No full textTelah dilakukan penelitian terhadap reaksi hidrodesulfurisasi (HDS) tiofen
menggunakan katalis CoMo/H-zeolit Y. Proses hidrodesulfurisasi (HDS) tiofen
dilakukan dalam reaktor sistem batch dengan variasi temperatur 200, 250, 300, 350,
400 oC dan variasi laju alir gas pembawa (H2) 40, 55, 70, 85, 100 mL/menit. Produk
cair dianalisis dengan gas chromatography mass spectrometry (GC-MS). Konversi
produk gas dihitung berdasarkan persentase berat produk gas terhadap umpan. Hasil
analisis GCMS produk hasil reaksi hidrosulfurisasi tiofen menunjukkan adanya 1
puncak utama tiofen pada waktu retensi 3,764 menit. Konversi gas maksimum
tercapai pada suhu 350oC sebesar 82,07% (b/b) dengan konstanta laju reaksi (k)
sebesar 49,56 menit-1
Studi Kinetika Antibakteri dari Hasil Pirolisis Cangkang Biji Jambu Mete terhadap Staphylococcus aureus
No full textResearch on kinetics antibacterial from pyrolysis product of cashew nut shell againts Staphylococcus aureus have been carried out. Cashew nuts are prepared by separating the shell and seeds for pyrolysis. The results of S. aureus antibacterial activity test results pyrolysis pyrolysis products shell cashew nut showed inhibition is different for each variation of the concentration of 12.5%, 25%, 50%, 75% and 100% with inhibition of successive 0.87; 0.97; 1.38; 1.47 and 1.61 (cm). Based on these results it can be said that the result of the pyrolysis of cashew nut shells provide a response inhibition that were at concentrations of 12.5 and 25%. While the concentration of 50%, 75%, and 100% response inhibitory power is included in the strong category on the growth of S. aureus. Order the reaction of the antibacterial activity of S. aureus from the pyrolysis products obtained cashew nut shell 0,3 with activity rate constant of 0.38. The concentration of pyrolysis products of pyrolysis results cashew nut shell the minimum recommended for use as an antibacterial S.aureus
Studi Kinetika Efektifitas Minyak Daun Cengkeh (Syzigium aromaticum) Sebagai Antifungi Candida albicans
No full textKinetic studies effectiveness clove leaf (Syzigium aromaticum) oil as antifungal Candida albicans have been done. The study have purpose to determine the reaction order, reaction constants (k) and relationship the concentration of clove leaf (Syzigium aromaticum) oil every time (At) with the initial concentration of of clove (Syzigium aromaticum) oil (Ao) and time (t) and equipped determination of the minimum concentration of clove leaf (Syzigium aromaticum)oil effective anti-fungus Candida albicans. The results shows the anti-fungal activity clove leaf (Syzigium aromaticum) oil on Candida albicans for each variation of the concentration 100%, 75%, 50% and 25% are 14.2 mm, 12.2 mm, 10.8 mm and 10.4 mm respectively. Reaction order as antifungal of the clove leaf (Syzigium aromaticum) oil on Candida albicans is 0.2112 with k = 5.0594. The minimum concentration of clove leaf (Syzigium aromaticum) oil as anti-fungal Candida albicans is 17.86%
Pengaruh Penambahan Tepung Tapioka Pada Pati Ubi Kayu (Manihot esculenta) Terhadap Pembuatan Plastik Biodegradable dan Karakterisasinya
No full textResearch on Biodegradable Plastic Characterization of Cassava Wastes (manihot esculenta) Substitution of Tapioca Flour. As Biodegradable Plastics Base Material. This study aims to determine the ratio of cassava starch to tapioca starch which produces the best biodegradable plastic which is then used for testing the physical and mechanical properties of biodegradable plastic film using 5% acetic acid. Comparison of cassava starch with tapioca flour used is 1 : 1; 1 : 1,5; 1 : 2; 1 : 2,5; 1 : 3. The best plastics are obtained by comparison of cassava starch with tapioca flour is 1 : 3. The characteristics of biodegradable plastics include physical characteristics consisting of thickness with value 0,273 mm, 0,286 mm, 0,413 mm, 0,280 mm, dan 0,510 mm. While the mechanical characteristics consist of tensile strength with value 0,22138 MPa, 2,10724 MPa, 0,78896 MPa, 3,25933 Mpa, dan 0,508 Mpa. Percent lengthening with value 42%, 32,8%, 55,6%, 20%, dan 31,6%. Based on the result of research, it can be concluded that the value of thickness, percent elongation, and tensile strength are influenced by the comparative formula used.Keywords: Biodegradable plastic, physical properties, mechanics, cassava starch, tapioca flou
Musta Tritonus : Livemusiikkikuunnelman tehokeinot
No full textOpinnäytetyöprojekti Musta Tritonus -livemusiikkikuunnelma yhdistää valmiiksi äänitetyn kuunnelman elävään musiikkiin. Projektin tekijä vastasi käsikirjoituksesta, säveltämisestä,
äänityksestä ja ohjauksesta. Projektiin osallistui 24 muusikkoa, jotka koostuivat pääasiassa Jyväskylän ammattikorkeakoulun opiskelijoista. Käsikirjoitus perustuu Kainuun ammattiopistossa opinnäytetyössä käytettyyn Mustan Tritonuksen Seura -tarinaympäristöön.
Suomessa kuunnelma on ollut taidemuotona pienessä mutta sisukkaassa asemassa. Projektin tavoite oli elävöittää kuunnelmakulttuuria, luoda elokuvamainen elämys näkörajoitteisille sekä tarjota projektiin osallistuville uusia kokemuksia. Kaksi ja puoli vuotta valmisteltu projekti huipentui kahteen esitykseen Jyväskylän ammattikorkeakoulun Hannikaissalissa joulukuussa 2013.
Opinnäytetyön kirjallisessa osassa raportoitiin kuunnelman vaiheet juonisynopsiksesta valmiikseen esitykseen. Kuunnelman eri tehokeinoja analysoitiin käsikirjoitusoppaan ja musikaalianalyysien avulla. Kirjallisessa osassa pyrittiin luomaan standardi, jonka avulla livemusiikkikuunnelman
tehojeinoja voitaisiin tarkastella. Merkittävimmät tehokeinot olivat draaman kaari, esityksen rytmitys sekä kuulijan huomion vangitsevat henkilöhahmot. Projektin massiivisuudesta johtuen Mustaa Tritonusta tuskin tullaan esittämään uudelleen lähiaikoina. Lisää Mustan Tritonuksen Seuran seikkailuja tullaan kuitenkin julkaisemaan tekijän kotisivuilla.The thesis project called Black Tritone: A Live Music Radio Drama combines a pre-recorded radio drama with live music. The project was written, composed, recorded and mixed by the author of this thesis. The project was participated by 24 musicians of whom most were studying at JAMK University of Applied Sciences. The script was based on a story environment called The Order of the Black Tritone used in an earlier thesis of the author completed in the Kainuu Conservatory.
In Finland radio drama as an art form has had a small and, yet, a headstrong position. The aim of the project was to invigorate the radio drama culture, create cinematic experiences for the visually challenged and give the participants new experiences. The project took two and a half years to finish and it was premiered twice at the chamber music hall of JAMK University of Applied Sciences, called
Hannikaissali, in December 2013.
The written part of the thesis dealt with the process of producing a live music radio drama from a plot synopsis to the complete performance. The radio drama’s methods of enhancement were analyzed based on script guides and a musical analysis. The written part aimed to create a standard
based on which those methods of a live music radio drama could be viewed. The most important enhancement methods were the dramatic structure, the performance's pacing and the characters that capture the listeners' attention. Due to its massiveness the Black Tritone is unlikely to be reperformed
in the near future. The stories of the Order of the Black Tritone will still continue on the author's website
Smooth nonparametric estimation under monotonicity constraints
No full textIn this thesis we address the problem of estimating a curve of interest (which might be a probability density, a failure rate or a regression function) under monotonicity constraints. The main concern is investigating large sample distributional properties of smooth isotonic estimators, which have a faster rate of convergence and a nicer graphical representation compared to standard isotonic estimators such as the constrained nonparametric maximum likelihood and the Grenander-type estimator. In the first part, we focus on the pointwise behavior of estimators for the hazard rate in the right censoring and Cox regression models, while the second part is dedicated to global errors of estimators in a general setup, which includes estimation of a probability density, a failure rate, or a regression function. We provide central limit theorems and assess the finite sample performance of the estimators by means of simulation studies for constructing confidence intervals and goodness of fit tests.Statistic
Synthesis of Methyl Ester Nitrate from Mahogany Seed Oil (Swietenia mahagoni Linn)
No full textNitration of methyl ester from mahogany oil (Swietenia mahagoniLinn) can be produced by Methyl Ester Nitrate (MEN), an additive that is useful for increasing Cetane Numbers in diesel fuel. This study aims to determine the yield of MEN that can be produced from mahogany seed oil after esterification, trans-esterification, and nitration and to identify the MEN compounds produced. Mahogany oil is obtained by pressing mahogany seeds and then degumming to remove the gum. Mahogany oil-free gum is esterified using methanol with the mole ratio of oil: methanol (1: 6), then trans-esterified, also using methanol with mole ratio (1:15) and a methyl ester is obtained. Then the methyl ester was nitrated with HNO3, sulfuric acid, and acetic anhydride to obtain a translucent reddish colored MEN product with a yield of 24.99%. The success of the synthesis was shown by the FTIR spectrophotometer in the presence of absorption at 1550 cm-1 which indicated the presence of the C-ONO2 group, the absorption at 1365 cm-1 indicated the presence of the NO2 group, and at 1118 cm-1 indicated the presence of the C-N group. The reaction mechanism that occurs during the predicted nitration reaction is an electrophilic substitution reaction and nucleophilic addition
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