5,298 research outputs found
Growth Improvement of Mung Bean (Vigna Radiata (L.) Wilczek R.) by Application of Mycofer and Phosphate Fertilizer
The objective of the research was to observe the effect of mycofer inoculation and the phosphate fertilizer on growth improvement of mung bean (Vigna radiata (L.) R. Wilczek). The research method used experimental method, which used randomize block design 2 x 7 factorial with 3 replications. The first factor was mycofer inoculation (M), which consisted of two levels, i.e. without mycofer inoculation (m0) and with mycofer inoculation (m1). The second factor was adding of phosphate fertilizer (P), which consisted of seven levels of doses, i.e. without adding of phosphate fertilizer (p0), 25 kg/ha (p1), 50 kg/ha (p2), 75 kg/ha (p3), 100 kg/ha (p4), 125 kg/ha (p5) and 150 kg/ha (p6). The observation parameter included the plant height, the leaf area, the dry weight, the number of pods, the seeds weight and the percentages of the root infection. The result showed that there was interaction between mycofer inoculation and the adding phosphate fertilizer to increase the plant height, the number of pods and the seeds weight. Phosphate fertilizer dose 75 kg/ha (p3) was the best dose for increasing the growth of mung bean plants inoculated mycofer on all parameters observed, except best phosphate fertilizers dose for the parameters of dry weight was 50 kg[1] / ha (p2)
Growth of beam-plasma instabilities in the presence of background inhomogeneity
We explore how inhomogeneity in the background plasma number density alters
the growth of electrostatic unstable wavemodes of beam plasma systems. This is
particularly interesting for blazar-driven beam-plasma instabilities, which may
be suppressed by inhomogeneities in the intergalactic medium as was recently
claimed in the literature. Using high resolution Particle-In-Cell simulations
with the SHARP code, we show that the growth of the instability is local, i.e.,
regions with almost homogeneous background density will support the growth of
the Langmuir waves, even when they are separated by strongly inhomogeneous
regions, resulting in an overall slower growth of the instability. We also show
that if the background density is continuously varying, the growth rate of the
instability is lower; though in all cases, the system remains within the linear
regime longer and the instability is not extinguished. In all cases, the beam
loses approximately the same fraction of its initial kinetic energy in
comparison to the uniform case at non-linear saturation. Thus, inhomogeneities
in the intergalactic medium are unlikely to suppress the growth of
blazar-driven beam-plasma instabilities.Comment: 10 pages, 6 figures, Accepted by ApJ, comments welcom
SHARP: A Spatially Higher-order, Relativistic Particle-in-Cell Code
Numerical heating in particle-in-cell (PIC) codes currently precludes the
accurate simulation of cold, relativistic plasma over long periods, severely
limiting their applications in astrophysical environments. We present a
spatially higher-order accurate relativistic PIC algorithm in one spatial
dimension, which conserves charge and momentum exactly. We utilize the
smoothness implied by the usage of higher-order interpolation functions to
achieve a spatially higher-order accurate algorithm (up to fifth order). We
validate our algorithm against several test problems -- thermal stability of
stationary plasma, stability of linear plasma waves, and two-stream instability
in the relativistic and non-relativistic regimes. Comparing our simulations to
exact solutions of the dispersion relations, we demonstrate that SHARP can
quantitatively reproduce important kinetic features of the linear regime. Our
simulations have a superior ability to control energy non-conservation and
avoid numerical heating in comparison to common second-order schemes. We
provide a natural definition for convergence of a general PIC algorithm: the
complement of physical modes captured by the simulation, i.e., those that lie
above the Poisson noise, must grow commensurately with the resolution. This
implies that it is necessary to simultaneously increase the number of particles
per cell and decrease the cell size. We demonstrate that traditional ways for
testing for convergence fail, leading to plateauing of the energy error. This
new PIC code enables us to faithfully study the long-term evolution of plasma
problems that require absolute control of the energy and momentum conservation.Comment: 26 pages, 19 figures, discussion about performance is added,
published in Ap
Prediksi Harga Komoditi Jagung Menggunakan K-nn dan Particle Swarm Optimazation sebagai Fitur Seleksi
Jagung merupakan komponen terpenting pakan pabrikan di dunia, terutama di daerah tropis. Fluktuasi harga produk pertanian akan mengakibatkan ikut berfluktuasinya pendapatan yang diterima oleh petani dari hasil produksi pertanian mereka. Salah satu upaya untuk mengantisipasi terjadinya fluktuasi harga adalah dengan melakukan peramalan harga. Peramalan harga dimaksudkan untuk melakukan prakiraan/prediksi harga masa depan dalam kurun waktu tertentu, dengan hasil keluaran berupa harga masa depan. metode KNN dapat digunakan untuk memprediksi harga komoditi. Hasil eksperiment yang telah dilakukan peneliti menunjukkan bahwa algoritma K-NN berbasis Particle Swarm Optimazation lebih baik dibandingkan dengan algoritma K-NN tanpa fitur seleksi. Berdasarkan hasil penelitian nilai RMSE terendah terdapat pada K-Nearest Neighbor berbasis Particle Swarm Optimazation untuk data jagung dengan variabel periode 4 parameter k 7 nilai population 5 Max Of Generation 40 dengan nilai RMSE 0,0
Importance of resolving the spectral support of beam-plasma instabilities in simulations
Many astrophysical plasmas are prone to beam-plasma instabilities. For
relativistic and dilute beams, the {\it spectral} support of the beam-plasma
instabilities is narrow, i.e., the linearly unstable modes that grow with rates
comparable to the maximum growth rate occupy a narrow range of wave numbers.
This places stringent requirements on the box-sizes when simulating the
evolution of the instabilities. We identify the implied lower limits on the box
size imposed by the longitudinal beam plasma instability, i.e., typically the
most stringent condition required to correctly capture the linear evolution of
the instabilities in multidimensional simulations. We find that sizes many
orders of magnitude larger than the resonant wavelength are typically required.
Using one-dimensional particle-in-cell simulations, we show that the failure to
sufficiently resolve the spectral support of the longitudinal instability
yields slower growth and lower levels of saturation, potentially leading to
erroneous physical conclusion.Comment: 7 pages, 9 figures, accepted by Ap
Uniform Diagonalization Theorem for Complexity Classes of Promise Problems including Randomized and Quantum Classes
Diagonalization in the spirit of Cantor's diagonal arguments is a widely used
tool in theoretical computer sciences to obtain structural results about
computational problems and complexity classes by indirect proofs. The Uniform
Diagonalization Theorem allows the construction of problems outside complexity
classes while still being reducible to a specific decision problem. This paper
provides a generalization of the Uniform Diagonalization Theorem by extending
it to promise problems and the complexity classes they form, e.g. randomized
and quantum complexity classes. The theorem requires from the underlying
computing model not only the decidability of its acceptance and rejection
behaviour but also of its promise-contradicting indifferent behaviour - a
property that we will introduce as "total decidability" of promise problems.
Implications of the Uniform Diagonalization Theorem are mainly of two kinds:
1. Existence of intermediate problems (e.g. between BQP and QMA) - also known
as Ladner's Theorem - and 2. Undecidability if a problem of a complexity class
is contained in a subclass (e.g. membership of a QMA-problem in BQP). Like the
original Uniform Diagonalization Theorem the extension applies besides BQP and
QMA to a large variety of complexity class pairs, including combinations from
deterministic, randomized and quantum classes.Comment: 15 page
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