Search results for "sampling"

L’indagine sulla mobilità turistica: strumenti di rilevazione

2010

This paper discusses the features and the structure of the interview forms used within the sample research on tourist mobility carried out in Sicily and Sardinia in years 2009 and 2010. The focus of the paper is on the strategies adopted by the research team in order to control non sampling errors. The limitations of the instruments respect to the secondary purposes of the research will be discussed as well.

The research on the mobility of tourists in Sicily: detection and estimation of non-sampling errors

2011

Intelligent Sampling for Vegetation Nitrogen Mapping Based on Hybrid Machine Learning Algorithms

2021

Upcoming satellite imaging spectroscopy missions will deliver spatiotemporal explicit data streams to be exploited for mapping vegetation properties, such as nitrogen (N) content. Within retrieval workflows for real-time mapping over agricultural regions, such crop-specific information products need to be derived precisely and rapidly. To allow fast processing, intelligent sampling schemes for training databases should be incorporated to establish efficient machine learning (ML) models. In this study, we implemented active learning (AL) heuristics using kernel ridge regression (KRR) to minimize and optimize a training database for variational heteroscedastic Gaussian processes regression (V…

Formal Contractual Agreements: A Transaction Cost Study of Tanzania Firms

2011

This is exploratory study that aims at examining formal contractual agreements for firms in Tanzania using Transaction cost theoretical approach. Transaction cost studies have rarely being done on firms in Africa and Tanzania in particular. Sampling frame used is from Tanzania revenue authority records for registered business 2008-2010. The study is centered on business - to business buyer -seller relations. Primary data were collected from buying side of this business relationship. Random sample of n =150 buyers were contacted through telephone calls and questionnaire were delivered personally. The response rate was about 65%. The findings suggest Transaction cost theoretical framework to …

An evaluation of the microscopical counting methods of the tape in hirst-burkard pollen and spore trap

1981

Abstract Three different sampling units in current use and different sampling strategies were tested. Randomly placed microscope fields are good in estimating the daily mean concentration, but very big sample size is needed. Traverses across the slide in systematic order are best to estimate the shortterm concentrations and diurnal variation. A formula for the estimation of the error in one transverse traverse is given. Twelve transverse traverses in systematic order is also enough to estimate the daily mean concentration. One or two traverses along the length of the slide give often unreliable estimates because of the irregularities in the transverse variation of the particle concentration…

Splines Computation by Subdivision

2015

In this chapter, fast stable algorithms are presented, which compute splines’ values at dyadic and triadic rational points starting from their samples at integer grid points. The algorithms are implemented by the causal-anticausal recursive filtering of initial data samples, which is followed by iterated application of FIR filters. Extension of the algorithms to the multidimensional case is straightforward. A natural application of the presented subdivision algorithms is for upsampling of signals and images. A few upsampling examples are provided.

Non-periodic Discrete Splines

2015

Discrete Splines with different spans were introduced in Sect. 3.3.1. This chapter focuses on a special case of discrete splines whose spans are powers of 2. These splines are discussed in more detail. The Zak transform provides an integral representation of such splines. Discrete exponential splines are introduced. Generators of the discrete-spline spaces are described whose properties are similar to properties of polynomial-spline spaces generators. Interpolating discrete splines provide efficient tools for upsampling 1D and 2D signals. An algorithm for explicit computation of discrete splines is described.

Non-periodic Discrete-Spline Wavelets

2015

This chapter describes wavelet analysis in the spaces of discrete splines whose spans are powers of 2. This wavelet analysis is similar to wavelet analysis in the polynomial-spline spaces. The transforms are based on relations between exponential discrete splines from different resolution scales. Generators of discrete-spline wavelet spaces are described. The discrete-spline wavelet transforms generate wavelet transforms in signal space. Practically, wavelet transforms of signals are implemented by multirate filtering of signals by two-channel filter banks with the downsampling factor 2 (critically sampled filter banks). The filtering implementation is accelerated by switching to the polyph…

Discrete-time multioverlapping controller design for structural vibration control of tall buildings under seismic excitation

2012

Published version of an article from the journal: Mathematical Problems in Engineering. Also available from the publisher:http://dx.doi.org/10.1155/2012/636878 In this paper, a computationally effective strategy to obtain multioverlapping controllers via the Inclusion Principle is applied to design discrete-time state-feedback multioverlapping LQR con- trollers for seismic protection of tall buildings. To compute the corresponding control actions, the proposed semidecentralized controllers only require state information from neighboring stories. This particular configuration of information exchange allows introducing a dramatic reduction in the transmission range required for a wireless imp…

INVESTIGATING MARKET POTENTIAL FOR STREAMING SUBSCRIPTION MODEL IN EMERGING ECONOMIES : A CASE OF NIGERIA

2018

Master's thesis Music management MU501 - University of Agder 2018 Building on two marketing theories: the product and marketing concept, this study conceptualizes how music sampling, consumers’ income and attitude affect streaming subscription in Nigeria. The aim is to test whether efficient market for streaming subscription could be developed in emerging economies and contribute to growth in the world digital music markets. The study used a binomial logistic regression to analyse 230 observations obtained from a survey data to estimate a conceptual framework. Results show that music sampling positively affect streaming subscription. Conversely, consumers’ income and attitude are both not s…