1,116,438 research outputs found
Population Assessment During the Adult Stage of the Alfalfa Blotch Leafminer, \u3ci\u3eAgromyza Frontella\u3c/i\u3e (Diptera: Agromyzidae)
This paper presents a sampling procedure for estimating adult populations of the alfalfa blotch leafminer, Agromyza frontella (Rondani). The method is based on counts of the flies as they emerge from the soil following adult metamorphosis, taken in a series offurmel traps. Analysis of sampling variability showed that 80 traps per field will give adequate precision for life table studies in alfalfa. The pattern of counts was overdispersed but conformed to the negative binomial distribution
Improved Orientation Sampling for Indexing Diffraction Patterns of Polycrystalline Materials
Orientation mapping is a widely used technique for revealing the
microstructure of a polycrystalline sample. The crystalline orientation at each
point in the sample is determined by analysis of the diffraction pattern, a
process known as pattern indexing. A recent development in pattern indexing is
the use of a brute-force approach, whereby diffraction patterns are simulated
for a large number of crystalline orientations, and compared against the
experimentally observed diffraction pattern in order to determine the most
likely orientation. Whilst this method can robust identify orientations in the
presence of noise, it has very high computational requirements. In this
article, the computational burden is reduced by developing a method for
nearly-optimal sampling of orientations. By using the quaternion representation
of orientations, it is shown that the optimal sampling problem is equivalent to
that of optimally distributing points on a four-dimensional sphere. In doing
so, the number of orientation samples needed to achieve a indexing desired
accuracy is significantly reduced. Orientation sets at a range of sizes are
generated in this way for all Laue groups, and are made available online for
easy use.Comment: 11 pages, 7 figure
Analysis of new direct sampling indicators for far-field measurements
This article focuses on the analysis of three direct sampling indicators
which can be used for recovering scatterers from the far-field pattern of
time-harmonic acoustic measurements. These methods fall under the category of
sampling methods where an indicator function is constructed using the far-field
operator. Motivated by some recent work, we study the standard indicator using
the far-field operator and two indicators derived from the factorization
method. We show the equivalence of two indicators previously studied as well as
propose a new indicator based on the Tikhonov regularization applied to the
far-field equation for the factorization method. Finally, we give some
numerical examples to show how the reconstructions compare to other direct
sampling methods
Sampling Technique for Larvae of the Alfalfa Snout Beetle, \u3ci\u3eOtiorhynchus Ligustici\u3c/i\u3e (Coleoptera: Curculionidae)
This paper presents a sampling procedure for estimating larval populations of the alfalfa snout beetle, Otiorhynchus ligustici. The method is based on counts of the larvae taken in 16 x 16 cm quadrats of soil during early fall when the grubs are in their final two instars and feeding just below the crowns of the plant. Analysis of sampling variability showed that 200 quadrats per field are necessary to obtain adequate precision for intensive population studies but that 50 quadrats are sufficient for survey work. The pattern of counts was overdispersed but conformed to the negative binomial distribution
Does an Analysis of the Pulsatile Secretion Pattern of Adrenocorticotropin and Cortisol Predict the Result of Transsphenoidal Surgery in Cushing’s Disease.
The endocrinological, surgical, and histological findings of patients with ACTH-dependent Cushing's disease were correlated with the pulsatile secretion pattern of ACTH and cortisol and the outcome after transsphenoidal pituitary surgery. A total of 28 patients were studied. The preoperative pulsatile secretion of ACTH and cortisol was assessed by sampling blood at 20-min intervals over 24 h. The pulsatile pattern of secretion was analyzed by the Cluster program. In 21 patients, an ACTH-secreting pituitary adenoma was identified and resected. Of these patients, 18 underwent clinical remission, and their cortisol secretion was suppressed to a normal level by low dose dexamethasone. Histological examinations in the patients with persistent disease revealed normal pituitary in 6 cases, nodular hyperplasia in 1, and ACTH-secreting pituitary adenoma in 3 cases. Analysis of the pulsatile pattern of ACTH and cortisol secretion did not reveal significant differences in timing, frequency, and/or amplitude of ACTH and cortisol pulses in normalized patients and those with persistent disease after surgery. It is concluded that analysis of the secretory pattern is not a suitable method for predicting the outcome of ranssphenoidal surgery in patients with ACTH-dependent Cushing's disease
Optimal sampling strategies for multiscale stochastic processes
In this paper, we determine which non-random sampling of fixed size gives the
best linear predictor of the sum of a finite spatial population. We employ
different multiscale superpopulation models and use the minimum mean-squared
error as our optimality criterion. In multiscale superpopulation tree models,
the leaves represent the units of the population, interior nodes represent
partial sums of the population, and the root node represents the total sum of
the population. We prove that the optimal sampling pattern varies dramatically
with the correlation structure of the tree nodes. While uniform sampling is
optimal for trees with ``positive correlation progression'', it provides the
worst possible sampling with ``negative correlation progression.'' As an
analysis tool, we introduce and study a class of independent innovations trees
that are of interest in their own right. We derive a fast water-filling
algorithm to determine the optimal sampling of the leaves to estimate the root
of an independent innovations tree.Comment: Published at http://dx.doi.org/10.1214/074921706000000509 in the IMS
Lecture Notes--Monograph Series
(http://www.imstat.org/publications/lecnotes.htm) by the Institute of
Mathematical Statistics (http://www.imstat.org
Analisis Perbandingan Pendapatan USAhatani Karet Pola Eks Upp Tcsdp dan Pola Swadaya di Desa Koto Damai Kecamatan Kampar Kiri Tengah Kabupaten Kampar
The purpose of this study was to analyze and compare the net income between rubber farmers Ex UPP TCSDP pattern and Swadaya pattern in the Koto Damai Village Kampar KiriTengah District Kampar Regency . The analysis is the analysis of net income and the t test . The method used is survey by census sampling technique as much as 20 farmers Pattern Governmental and simple random sampling technique as much as 20 farmers Ex UPP TCSDP.Analysis results showed an average net income of farmers rubber Ex UPP TCSDP Pattern is 33 % larger than the SwadayaPattern . T test is greater than t table at the level of 95 %, which means there is a real difference in net income between rubber farmers Ex UPP TCSDP Pattern and Swadaya Pattern, income disparity is due to the difference in the amount of rubber production and the use of production factors between the second pattern rubber farming
Progress in high temperature speckle-shift strain measurement system
A fast, easy to use speckle tracking system is under development for the speckle-shift strain measurement technique. Preliminary correlation tests on wire specimens show strong correlations of well-developed speckle patterns. Stable cross-correlations were obtained from a tungsten filament at 2480 C. An analysis of the optical system determines the minimum required sampling frequency of the speckle pattern to be 2.55 pixels per speckle
Probabilistic Latent Tensor Factorization Model for Link Pattern Prediction in Multi-relational Networks
This paper aims at the problem of link pattern prediction in collections of
objects connected by multiple relation types, where each type may play a
distinct role. While common link analysis models are limited to single-type
link prediction, we attempt here to capture the correlations among different
relation types and reveal the impact of various relation types on performance
quality. For that, we define the overall relations between object pairs as a
\textit{link pattern} which consists in interaction pattern and connection
structure in the network, and then use tensor formalization to jointly model
and predict the link patterns, which we refer to as \textit{Link Pattern
Prediction} (LPP) problem. To address the issue, we propose a Probabilistic
Latent Tensor Factorization (PLTF) model by introducing another latent factor
for multiple relation types and furnish the Hierarchical Bayesian treatment of
the proposed probabilistic model to avoid overfitting for solving the LPP
problem. To learn the proposed model we develop an efficient Markov Chain Monte
Carlo sampling method. Extensive experiments are conducted on several real
world datasets and demonstrate significant improvements over several existing
state-of-the-art methods.Comment: 19pages, 5 figure
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