Number Of Reference Points Research Articles

Hierarchical modelling of archaeomagnetic data and curve estimation by moving average technique

A Bayesian hierarchical modelling is proposed for the different sources of scatter occurring in archaeomagnetism, which follows the natural hierarchical sampling process implemented by laboratories in field. A comparison is made with the stratified statistics commonly used up to now. The Bayesian statistics corrects the disturbance resulting from the variability in the number of specimens taken from each sample or site. There is no need to publish results at sample level if a descending hierarchy is verified. In this case, often verified by archaeomagnetic data, only results at site level are useful for geomagnetic reference curve building. Typically, a study with at least 20 samples will give an α95i 5 per cent close to the optimal α95i for a fixed site number mi and if errors are random with zero mean (no systematic errors). The precision on the curve itself is essentially controlled, through hierarchical elliptic statistics, by the number of reference points per window and by dating errors, rather than by the confidence angles α95ij at site level (if a descending hierarchy). The Bayesian elliptic distribution proposed reveals the influence of the window width. The moving average technique is well adapted to numerous and very well dated data evenly distributed along time. It is not a global functional approach, but a (linear) local one.

Optimization of scaled probabilistic cleaning methods

The scaled probabilistic cleaning method is one of nonlinear noise reduction methods for chaotic time series, whose calculation quantity and needed memory volume increase exponentially with the number of reference points and the embedding dimension because of the joint processing of all data points in phase space. An optimized method, which modifies the estimation of forward probabilities and transition probabilities is proposed, and the computing workload is reduced to about 0.27 times that of the original method without degradation in noise reduction performance. The implementation of the method for the long time series also reduces the needed memory size.

適応的累積関数近似によるロバスト最適設計における計算効率の改善法

This paper proposes a new scheme for saving the computation cost of robust optimal design by using cumulative function approximation. Since robust optimal design seeks the optimal solution considering the variation of functions over distribution region, it requires much more computation cost than nominal optimal design because evaluation of each tentative solution requires iteration of system analysis at a certain number of reference points within a distribution region. The proposed scheme dramatically saves such computational cost by substituting system analysis at respective reference points with a cumulative function approximation that has an ability of gradually improving fidelity of approximation through gradual, adaptive and cumulative addition of sample points. In this paper, the outline of the scheme is discussed, the procedures of mini-max type robust optimal design and Voronoi diagram based cumulative function approximation are reviewed, and their hybridization for the purpose is described. Finally, numerical examples are demonstrated to ascertain its effectiveness.

Localization of Aircraft on an Electronic Navigation Display Using Verbal Communication

The present study examined the use of a track-up aircraft navigation display in localizing the position of a second aircraft given only verbal communication information of its position. Two experiments examined the role of map rotation, number of available fixed reference points, and the relative position between two aircraft on the ability to localize the position of the target aircraft. Both experiments confirmed that performance declined with map rotations other than north-up, with the poorest performance at 90° of rotation. The number of reference points available increased the response time for localization but did not improve accuracy. The relative position of the two aircraft also affected performance, finding that aircraft located on opposite sides of a reference point or aligned with one of the 4 cardinal compass directions resulting in the fastest and most accurate localization.

Reference Point Logistic Regression and the Identification of DNA Functional Sites

Logistic regression is frequently used in pattern recognition problems to model conditional probabilities of class membership given features observed. While performing well in many applications, logistic regression is limited to a relatively simple parametric model and is often not suitable for complex applications. This article describes a generalization of logistic regression based on reference point logistic (RPL) functions; i.e., normalized exponential functions of squared distance between the vector of observed features and reference points in the feature space. This generalization is closely related to a recently developed method for constructing classification rules. RPL regression and classification methods are based on the same parametric family of functions and the same optimization technique. The methods differ primarily in their optimality criterion and interpretation. Both methods are highly flexible. By adjusting the number of reference points, the complexity of conditional probability models and classification boundaries can be adapted to the problem at hand. Comparisons are made with related techniques from statistics and neural networks. As an illustration, RPL regression is applied to the problem of identifying functional sites at the boundaries of protein coding regions in genomic DNA.

Bias in Proportion Judgments with Pie Charts: The Cyclical Power Model

Subjects were shown pie charts with tickmarks at two, three, four, or eight evenly-spaced locations. The tickmarks were located around the edge of the pie, on a line where the subject responded, or both. A cyclical power model based on Stevens' law was used to account for the observed bias patterns. The model proposes that subjects use reference points to constrain the range of values used in the judgment. When more than two reference points are used, the model predicts multiple cycles of bias. The results showed that increasing the number of reference points on the response line from two to four changed the number of bias cycles, while the estimated Stevens exponent remained approximately constant at 0.8. The model can be used as a tool to assess how graphs, dials, and meters are read.

Two houses both alike in dignity: Reginald Pole and Edmund Harvell

ABSTRACTIn the period 1520–50 there was a large English community in the Veneto. This has traditionally been associated with the household of Reginald Pole, who is believed to have dispensed learning and patronage to those who went to the University of Padua in search of a continental education. However, an examination of both primary and secondary sources for the life of Pole suggests that he was only one of a number of reference points for young English scholars and travellers. Of equal, and perhaps greater, importance was the household of Edmund Harvell, a merchant who became English ambassador to the Republic. His household was philo-protestant in tone, and linked to Venetian dissenters and literary circles. These two central figures presented English scholars with the chance to experience the varying strands of Venetian political and religious philosophy at a time of great intellectual vitality. Men such as Richard Morison and Thomas Starkey returned home to write books about English government and society. When their work is set against the Venetian milieu of Harvell and Pole, we can gain a greater understanding of those Venetian influences which underpinned English political thought in the Tudor period and beyond.

Numerical Simulation for Jets Exhausting into a Two-Dimensional Channel with Self-Induced Oscillation. 2nd Report. Application of Neural Network.

An application of a neural network to jets with self-induced oscillation exhausting into a two-dimensional channel is presented. No established method nor suitable parameter to control flip-flop jets is known. One new approach for neural networks is a recurrent network. We find that if the flip-flop is periodic, the recurrent network can be useful to reproduce the original periodic orbit obtained by the time delay method. Another application of the recurrent network employed the flow pattern from velocity fields of the neural network. In this case, the results depend on the number of reference points and on the number of teaching patterns in computed fields given. A promising result is obtained for the control of flip-flop jets using a recurrent network.

Characteristics of Dimension Functions Associated With Cutting Measurements

The information dimension, D(0), of attractors associated with orthogonal turning is determined from experimental tool-workpiece relative acceleration data. Let E≡dimension of a delay coordinate space, n≡number of generic data points and m≡ number of reference points on the attractor. It is shown that properties of D(0) as a function of E, denoted by D(0):E, are unchanging, invariant, over large intervals of n and m. The qualitative properties of D(0):E discriminate between various cutting cases. This discrimination can be based on relatively small data sets. The computation of D(0) is shown to be robust in the sense that estimated values of D(0) are invariant or slowly varying over intervals of n and m.

Acquisition of locational information about reference points during locomotion with and without a concurrent task: effects of number of reference points.

Maintenance of orientation relative to reference points along a locomotion path and acquisition of locational information about these reference points were investigated by requiring subjects with and without a concurrent backwards counting task to walk in alleys and estimate direction and distance to the reference points when stopped. One or three reference points were presented on each trial in different groups of subjects. Acquisition of locational information was indicated by decreased latencies and variable errors with repeated exposure to the same locomotion path. Neither the larger number of reference points nor the concurrent task seemed to affect acquisition, but both lead to increased latencies indicating that the subjects under these conditions were unable to keep track of the locations of the reference points whilst walking. However, they may still have been able to infer these locations after the locomotion path had been traversed.

Excavations at El-Medeinah, Ancient Surt 1977

Excavations at El-Medeinah, ancient Surt (in previous reports erroneously called Medinat Sultan) took place between July 11 and August 6th 1977. The excavations were financed by the Department of Antiquities of Libya and by the Society for Libyan Studies. Participants of the excavations were Mr. Abdulhamid Abdussaid, Technical Director of the Department of Antiquities, Libya, Mr. Masoud Shagluf, Controller of Antiquities, Benghazi, Dr. Géza Fehérvári, School of Oriental and African Studies, University of London on behalf of the Society for Libyan Studies, Mr. Idris Ahmad Badi, Inspector of Antiquities, Benghazi, Mr. Michael Blyth and Mrs. Marta Kozary Blyth, Architects, Miss Marga Foley, Conservation student, Institute of Archaeology, University of London, Miss Caroline Ballingal, student, School of Oriental and African Studies, University of London and Mrs. Iren Fehérvári.The aims of the season's work were:1. to prepare an overall survey map of the site,2. to prepare for publication the previously excavated pottery, and3. to open a trial trench in the mosque area in order to investigate earlier occupation levels, and a second one inside the mosque to establish the existence of a ṗre-Fāṭimid mosque.With regard to the survey of the site, Professor Lucien Golvin of the University of Aix-en-Provence began such work on the site in June, 1975 and laid down a number of reference points on a 50 m grid. It was decided that the present survey should be based on Professor Golvin's grid, and implemented as necessary. A new reference system was evolved which will be used in future excavations. A contour map of 1:1000 was produced which extends beyond the suggested line of the city walls as they were set by the Department of Antiquities under the direction of Dr. Mohammad Mostafa. The map depicts the contours at 50 cm intervals and includes all the previously excavated areas and visible features of the site (Fig.1).

Contribution à la pondération des points d'observation

In the plate reduction, when a polynomial transformation is used, the minimum of the effect of an error calculated at the point where the error is acting does not always coincide with the plate centre (Debehogne, 1972). We have proved this property by means of a network (fictitious stars). Here, we will present a theoretical demonstration for the first and second order (straight line and parabole). For the first order, the minimum coïncides with the reference points centre (table I). For the second order, the minimum coïncides with this centre only when B = [formule], where n is the number of reference points, xt the abcisses, [xt2] = [formule] i Moreover, there are two maxima symetrically displayed around the centre for n < B. When B < n < 3 B, we have a maximum at the centre and two minima. See this extrema values in table II.

Precision of selenodetic frames of reference

The number of reference points for the fixing of a selenodetic reference frame in the Moon’s body is estimated. It is shown that, for this purpose, from 40 to 100 reference points are sufficient. Precision of the selenodetic coordinate transformations from one system to another is also analysed.

RESIDUAL GRAVITY IN THEORY AND PRACTICE

A precise definition of residual gravity is given and in a form most suitable for numerical application. Some pains are taken to show that the residual‐gravity picture one obtains depends on the method used in obtaining it and that there are many ways in which this may be done. Several examples from actual work on developed oil fields are given in the form of figures and maps to bear out the above statement. Conclusions are drawn as to the relative order of sensitivity of several factors entering into the computations in determining a given residual picture. Factors considered in this paper are (1) size of unit figure, (2) kind (or shape) of unit figure, (3) density of reference net; that is, number of reference points per unit area, and (4) sensitivity of reference points to lateral displacement on gravity map.