Review Pemanfaatan Design Expert untuk Optimasi Komposisi Campuran Minyak Nabati sebagai Bahan Baku Sintesis Biodiesel

Pencampuran berbagai jenis minyak nabati untuk sintesis biodiesel merupakan salah satu upaya pencarian sumber energi alternatif terbarukan. Campuran berbagai macam minyak nabati lebih potensial karena ketersediaannya masih melimpah dan kurang dimanfaatkan. Campuran minyak nabati yang dapat digunakan sebagai bahan baku antara lain: minyak jarak pagar, minyak nyamplung, dan minyak jelantah. Komposisi campuran ditentukan dan dioptimasi menggunakan metode simplex lattice design dengan total campuran tertentu. Data yang akan didapat yaitu data pengaruh masing-masing campuran minyak terhadap penurunan bilangan FFA saat reaksi esterifikasi. Metode simplex lattice design merupakan salah satu metode yang terdapat di dalam software Design Expert 10.0 yang digunakan untuk optimasi formula pada berbagai jumlah komposisi bahan yang berbeda. Sintesis biodiesel dijalankan berdasar design of experiment yang dihasilkan oleh program Design Expert 10.0. Kegunaan metode simplex lattice design diantaranya: penentuan formula, mengoptimalkan variabel formulasi dan mengetahui jumlah run, menjaga konsentrasi total tetap konstan. ANOVA (Analysis of variance) dilakukan untuk menentukan signifikansi analisis respon antar variabel dan dapat mengetahui model yang disarankan. Desirability merupakan nilai fungsi yang menunjukkan kemampuan program untuk memenuhi keinginan berdasarkan kriteria yang ditetapkan pada produk akhir. Nilai desirability yang semakin mendekati nilai 1,0 menunjukkan kemampuan program untuk menghasilkan produk yang dikehendaki semakin sempurna

Numerical cubature from Archimedes' hat-box theorem

Archimedes' hat-box theorem states that uniform measure on a sphere projects to uniform measure on an interval. This fact can be used to derive Simpson's rule. We present various constructions of, and lower bounds for, numerical cubature formulas using moment maps as a generalization of Archimedes' theorem. We realize some well-known cubature formulas on simplices as projections of spherical designs. We combine cubature formulas on simplices and tori to make new formulas on spheres. In particular $S^n$ admits a 7-cubature formula (sometimes a 7-design) with $O(n^4)$ points. We establish a local lower bound on the density of a PI cubature formula on a simplex using the moment map. Along the way we establish other quadrature and cubature results of independent interest. For each $t$, we construct a lattice trigonometric $(2t+1)$-cubature formula in $n$ dimensions with $O(n^t)$ points. We derive a variant of the M\"oller lower bound using vector bundles. And we show that Gaussian quadrature is very sharply locally optimal among positive quadrature formulas.Comment: Dedicated to Krystyna Kuperberg on the occasion of her 60th birthday. This version has many minor change

Synthesis of CdS/L-cys nanoparticles colloid solutions with predetermined optical properties

The purpose of this paper is to summarize experimental data of CdS/L-cystein nanoparticles (NPs) colloid solutions optical properties as function of 3-component mixture (Cd2+–S2 –L-cys) content. The NPs synthesis was carried out at pH 11 in the wide composition range based on literature data. The influence of the solutions composition on the colloids stability and the CdS/l-cys NPs size was monitored by absorption and fluorescence spectra observation at room temperature and studied by TEM. A polynomial model was used for the responses produced from Scheffe’s simplex lattice design with fourth degree terms. The paper also compares the results of two statistical-experimental methods, namely 2D Scheffe’s simplex-lattice design and 3D-plot by STATISTICA v6 program. Both models were found to be adequate for prediction the optical properties of the solutions but with various approximation level

Optimasi Kombinasi Aspartam- Tropicana Slim® Sebagaipemanis Dalam Formulasi Tablet Effervescent Dari Ekstrak Kelopak Bunga Rosella (Hibiscus Sabdariffa L.) Dengan Metode Simplex Lattice Design

Flower calyces Rosela (Hibiscus sabdariffa L) is a traditional medicine as anti-hypertension is now widely used in various preparations. This research alms to create effervescent tablets of flower calyces extract Rosela (Hibiscus sabdariffa L) with a stable characteristic of simplex lattice design method. Formula optimization used simplex lattice design because this method does not require much effort and money. Then extracts are tested their physical properties including appearance, viscosity, and moisture content. Granules obtained are tested it flow time. While testing physical properties include the effervescent tablet weight uniformity, tablet hardness, friability, and time dissolve tablet in water. To get the equation to obtain the profile properties - the physical properties of effervescent tablets, then the simplex lattice design based on the formula that made three Fl (aspartame 50%: 50% Tropicana Slim®), Fll (aspartame 100%: 0% Tropicana Slim®) and Fill (0%aspartame: 100% Tropicana Slim®). Formula optimization is done by using variable hardness, friability, and time dissolve with each - each coefficient of 0.33, 0.32, 0.35. From the results of optimization using simplex lattice design method obtained a total response value (R)Is the concentration of aspartame 40%: 60% Tropicana Slim® which is the optimum formula. Besides the active compounds of flavonoids routine can still be found in the effervescent tablet is produced. Respondents most preferred formula is formula II, with 50% aspartame and 50% Tropicana Slim®

polyDB: A Database for Polytopes and Related Objects

polyDB is a database for discrete geometric objects. The database is accessible via web and an interface from the software package polymake. It contains various datasets from the area of lattice polytopes, combinatorial polytopes, matroids and tropical geometry. In this short note we introduce the structure of the database and explain its use with a computation of the free sums and certain skew bipyramids among the class of smooth Fano polytopes in dimension up to 8.Comment: 15 page

Synthesis of CdS/L-cys nanoparticles colloid solutions with predetermined optical properties

The purpose of this paper is to summarize experimental data of CdS/L-cystein nanoparticles (NPs) colloid solutions optical properties as function of 3-component mixture (Cd2+–S2 –L-cys) content. The NPs synthesis was carried out at pH 11 in the wide composition range based on literature data. The influence of the solutions composition on the colloids stability and the CdS/l-cys NPs size was monitored by absorption and fluorescence spectra observation at room temperature and studied by TEM. A polynomial model was used for the responses produced from Scheffe’s simplex lattice design with fourth degree terms. The paper also compares the results of two statistical-experimental methods, namely 2D Scheffe’s simplex-lattice design and 3D-plot by STATISTICA v6 program. Both models were found to be adequate for prediction the optical properties of the solutions but with various approximation levels

Representing Patterns of autonomous agent dynamics in multi-robot systems

It is proposed that vocabularies for representing complex systems with interacting agents have a natural lattice hierarchical structure. We investigate this for the example of simulated robot soccer, using data taken from the RoboCup simulation competition. Lattice hierarchies provide symbolic representations for reasoning about systems at appropriate levels. We note the difference between relational constructs being human supplied versus systems that abstract their own constructs autonomously. The lattice hierarchical representation underlies both