Pair Of Coordinates Research Articles

Interplay of classical and quantal features within the coherent-state model

The classical and quantal features of a quadrupole coherent state and its projections over angular momentum and boson number are quantitatively analyzed in terms of the departure of the Heisenberg uncertainty relations from the classical limit. This study is performed alternatively for two choices of the pairs of conjugate coordinates. The role of deformation as mediator of classical and quantal behaviors is also commented. Although restoring the rotational and gauge symmetries makes the quantal features manifest dominantly for small deformation, these are blurred by increasing the deformation which pushes the system toward a classical limit.

Ladder Operators for Quantum Systems Confined by Dihedral Angles

We report the identification and construction of raising and lowering operators for the complete eigenfunctions of isotropic harmonic oscillators confined by dihedral angles, in circular cylindrical and spherical coordinates; as well as for the hydrogen atom in the same situation of confinement, in spherical, parabolic and prolate spheroidal coordinates. The actions of such operators on any eigenfunction are examined in the respective coordinates, illustrating the possibility of generating the complete bases of eigenfunctions in the respective coordinates for both physical systems. The relationships between the eigenfunctions in each pair of coordinates, and with the same eigenenergies are also illustrated.

An approach to the validation of computational solid mechanics models for strain analysis

The need to provide strong evidence of the validity of predictions from computational solid mechanics models used in engineering design decisions is discussed. A new procedure is proposed, based on image decomposition, for reducing the dimensionality of strain field data from models and experiments and then comparing the resultant feature vectors via a simple linear correlation in which validation is deemed to be achieved when the coordinate pairs from the two feature vectors lie within a scatter band defined by the minimum measurement uncertainty. The procedure is illustrated by some simple examples that allow the advantages and drawbacks of the approach to be highlighted. It is anticipated that the procedure could become part of a corporate plan or regulatory process for verification and validation of computational solid mechanics models.

Binding weakly interacting partners: a study of Ca–He2 and its isotopomers

We present in this paper binding energies and structures of non-rotating weakly bound 40Ca– n He2 triatomic complexes. Two kind of systems are discussed: bosonic (n = 4) and fermionic (n = 3) complexes at its singlet state (nuclear spin S = 0). Three different coordinate systems and methods have been used to solve the relevant Schrodinger equation: variational calculations (1) using satellite coordinates and a discrete variable representation of radial functions; (2) employing pair coordinates and products of distributed Gaussian functions as basis functions; and (3) variational/Diffusion Monte Carlo calculations in Cartesian coordinates. The potential energy surface is represented as the addition of pair potentials. By using the most realistic interaction between each pair of particles, present results from the three methods are in fair agreement. Only two bound states for each system are found in our computations.

A system for automatic recording and analysis of motor activity in rats

We describe the design and evaluation of an electronic system for the automatic recording of motor activity in rats. The device continually locates the position of a rat inside a transparent acrylic cube (50 cm/side) with infrared sensors arranged on its walls so as to correspond to the x-, y-, and z-axes. The system is governed by two microcontrollers. The raw data are saved in a text file within a secure digital memory card, and offline analyses are performed with a library of programs that automatically compute several parameters based on the sequence of coordinates and the time of occurrence of each movement. Four analyses can be made at specified time intervals: traveled distance (cm), movement speed (cm/s), time spent in vertical exploration (s), and thigmotaxis (%). In addition, three analyses are made for the total duration of the experiment: time spent at each x-y coordinate pair (min), time spent on vertical exploration at each x-y coordinate pair (s), and frequency distribution of vertical exploration episodes of distinct durations. User profiles of frequently analyzed parameters may be created and saved for future experimental analyses, thus obtaining a full set of analyses for a group of rats in a short time. The performance of the developed system was assessed by recording the spontaneous motor activity of six rats, while their behaviors were simultaneously videotaped for manual analysis by two trained observers. A high and significant correlation was found between the values measured by the electronic system and by the observers.

In-silico designing of acyclic nucleoside phosphonates and their anti-HIV potential

Method The object of our study is to develop newer nucleoside phosphonate analogs bearing unsaturation and modifications in heterogenous bases and prediction of their antiHIV potential. Designing is done keeping the Lipinski’s Rule of Five in focus. The diphosphates of compounds have been docked into the active site of wild type HIVRT (PDB: ID 2B6A). The forcefield of the Chemistry at Harvard Macromolecular mechanics (CHARMm) was applied to 3D models of PD HIV RT-nevirapine complex and synthesized ligands. The energy function is based on separable internal coordinate terms and pair wise non-bond interaction terms.

Identification, reconstruction and validation of insertions in resequencing projects with GapFiller

Motivations. A difficult problem in resequencing projects is the identification, reconstruction, and validation of inserted regions within an unknown genome, with respect to a reference one. In most organisms, many structural variants are found in highly repetitive regions of the genome, making their identification difficult. Recent studies demonstrate the feasibility of detecting structural variants using next-generation, paired-end sequencing reads. Reconstructing completely or at least both ends straddling the inserted sequence is a first validation step. Both reconstruction and validation are still weak in existing tools. Methods. GapFiller is a tool developed to fill with a single sequence the gap between paired reads produced by NGS technologies. It is based on a seed-and-extend scheme and it implements techniques to avoid errors in produced contigs. A contig spanning the whole gap is dubbed certified if the mate of the seed read is found. As a matter of fact, GapFiller can be applied to whatever pair of sequences known to lay at an estimated distance, as long as a set of uniformly distributed short reads are provided as input to fill the gap. Our pipeline to reconstruct and validate insertions in a resequenced individual is divided in two main phases: the first one consists in constructing contigs straddling the borders of putative insertions, the second one in filling the gap between them. Before running the pipeline we need to determine locations of putative insertions and to extract the reads aligning around them. More specifically, if insertions in organism A with respect to organism B are to be investigated, we first extract locations of putative insertions, using a tool designed for this purpose (i.e., BreakDancer). Then the reads of A are aligned against the reference B and those mapping next to insertions are extracted, as well as their, possibly unmapped, mates, with the proper orientation. GapFiller is then run twice: a first time to fill the gap between the extracted paired reads in order to reconstruct the borders of each insertion, and a second time to reconstruct the sequence between the certified contigs produced. In the latter phase we treat contigs on the left and on the right side of an insertion as if they were the two pairs of a paired read, respectively, and GapFiller's output will be a super-contig. The event that the super-contig obtained starting from the left contig finally matches against the right one, represents an evidence that we have reconstructed the desired sequence. Clearly, the level of confidence is a function of the number of super-contigs for each (putative) insertion. Moreover, as an important byproduct, we have the assembly of the missing sequence. Results. In order to check correctness we tested our pipeline on a real dataset, consisting of a 30x coverage of paired reads from the Vitis vinifera variety PN40024 (485Mbp), for which the reference genome is known. Using BreakDancer we extracted pairs of coordinates on the reference corresponding to deletions on the resequenced variety Sangiovese. This way we simulated insertions in PN40024, with the advantage of being able to check if the sequences assembled by GapFiller were correct, by simply aligning them against the reference. As a preliminar validation step, for each sequence S identifying a putative insertion we computed the maximal tails of S covered by the (certified) contigs produced in the first phase, i.e. we consider only the contigs consisting of paired reads whose gap has been successfully filled. In particular, we identified 800 putative insertions for which we were able to correctly assemble at least 200bp on both tails. The second phase is more difficult as we try to reconstruct (probably highly) repetitive regions. For a few pairs of left and right contigs we were able to entirely reconstruct the inserted sequence, with respect to the reference genome PN40024. However, this point requires a deeper analysis and we are currently working on the improvement of the final step of our pipeline.

Investigating impacts of positional error on potential health care accessibility

Accessibility to health services at the local or community level is an effective approach to measuring health care delivery in various constituencies in Canada and the United States. GIS and spatial methods play an important role in measuring potential access to health services. The Three-Step Floating Catchment Area (3SFCA) method is a GIS based procedure developed to calculate potential (spatial) accessibility as a ratio of primary health care (PHC) providers to the surrounding population in urban settings. This method uses PHC provider locations in textual/address format supplied by local, regional, or national health authorities. An automated geocoding procedure is normally used to convert such addresses to a pair of geographic coordinates. The accuracy of geocoding depends on the type of reference data and the amount of value-added effort applied. This research investigates the success and accuracy of six geocoding methods as well as how geocoding error affects the 3SFCA method. ArcGIS software is used for geocoding and spatial accessibility estimation. Results will focus on two implications of geocoding: (1) the success and accuracy of different automated and value-added geocoding; and (2) the implications of these geocoding methods for GIS-based methods that generalise results based on location data.

Perspective Depth Extraction of Points on a Surface Under an Instantaneous Rigid Body Transformation

Abstract We consider the computational problem of finding the point in 3D-space on a transformed surface corresponding to a coordinate pair given in a perspective mapping. The transformation is a rigid body transformation that is assumed to be small and vary. Initially, it is unknown but when it becomes known, the output must be accurate and quickly returned. Therefore, the computations are adapted for those conditions. Preprocessed shape information about the surface is computed in a perspective mapping where the surface is in an original position. We are discussing algorithms for solving the considered problem.

Method to Determine Handwriting Stroke Types and Directions for Early Detection of Handwriting Difficulty

The early detection of children suffering from handwriting difficulty is important for timely intervention to avoid negative impact in learning. In this paper, a method that identified the types of strokes involved in writing Latin alphabets and its drawn direction is proposed to detect handwriting difficulty based on the errors formed during character drawing. The method accepts stroke inputs of point series recorded in xy-coordinates, and categorized the input strokes into three categories, which are simple straight lines, curve lines, and complex straight lines, i.e. combination of two or more simple sstraight lines that are drawn continuously in one stroke. The classification is done based on the angle difference detected between series of points in each stroke. Next, the type of the handwriting stroke and direction to produce each stroke will be identified through the rrelationship of consecutive coordinate pairs. The proposed method works well in classifying and identification of simple straight line strokes, while additional features are needed to improve the accuracy in recognition of curve and complex straight lines.

Analytical resolution of the electrical four-parameters model of a photovoltaic module using small perturbation around the operating point

In this paper, a new real-time curve fitting method for photovoltaic (PV) modules is presented. The method solves the four-parameters photovoltaic cell model without scanning the entire I–V curve, without sensing irradiance or temperature and with no need of any manufacturer data. Only six pairs of voltage and current coordinates are needed to obtain the photovoltaic module parameters in any conditions of illumination, temperature or degradation. Once the electrical model is known, a new technique to compute the maximum power point (MPP) of the module is devised. This method is suitable for real time applications where the I–V curve of the module and the MPP can be extracted at any moment without affecting the operation of the system. The theory that supports the estimator and experimental results are presented in this work.

Astrometric results of observations at Russian observatories of mutual occultations and eclipses of Jupiter’s Galilean satellites in 2009

In 2009, in five Russian observatories photometric observations of Jupiter’s Galilean satellites during their mutual occultations and eclipses were carried out. Based on these observations, an original method was used to ascertain astrometric results such as the difference between the coordinates of pairs of satellites. Fifty-three phenomena were successfully observed. A total of 94 light curves of satellites were measured. The error in the coordinates of satellites due to random errors in photometry, calculated on all data obtained, was 0.041″ in right ascension and 0.046″ in declination. The discrepancies between the theory and observations in these coordinates was found to be 0.060″ and 0.057″, respectively. The results were uploaded to the common database for all observations of natural satellites of planets at the Natural Satellites Data Center (NSDC), which is available online at http://www.sai.msu.ru/neb/nss/index.htm. For the first time in the practice of photometric observations of satellites in epochs of mutual occultations and eclipses a new method of observation was tested, which eliminates from astrometric results the major systematic errors caused by an inaccurate account of the background level. The tests were conducted in the Terskol Observatory and the observatory of the Crimean laboratory of the Sternberg State Astronomical Institute of the Moscow State University. The application of the new method showed that the elimination of the background level at these observatories was carried out correctly.

Analyzing local image statistics via maximum-entropy constructions

AbstractBecause the space of signals that the visual system encounters is high-dimensional, investigations of visual processing and perception must utilize a sampling strategy. One kind of approach begins with a class of models for input-output relations, and then chooses a stimulus ensemble such as white noise that enables efficient determination of model parameters. A second kind of approach begins with the explicit recognition that it is important to understand the visual system in the context of the inputs under which it functions and evolves; this motivates the use of naturalistic stimulus ensembles. Neither approach alone is sufficient: models built from ensembles such as white noise provide only a fair account of responses to natural scenes, and the complex statistical structure of naturalistic stimuli makes it difficult to isolate computational mechanisms.Here we present a step in the direction of bridging this gap. Our starting point is a recent analysis of the multipoint correlations of natural images (Tkačik et al., 2010) which showed that four-point correlations in specific configurations (“gliders”) capture the informative local statistics in binarized natural images. We focus on one such glider, 2x2 windowpanes. The corresponding set of image statistics has ten parameters, and we determine a set of coordinates for this space that are calibrated for equal salience to an ideal observer. Via maximum-entropy constructions, we generate ensembles that isolate the individual coordinates and coordinate pairs. We then characterize the perceptual salience of these image statistics, alone and in combination, via a texture-segmentation task (Chubb et al., 2004). Three main findings emerge. First, observers are sensitive to image statistics of low and high-order. Second, the pattern of sensitivities, which is not simply order-by-order, is remarkably constant across observers. Third, image statistics interact at a perceptual level in a way that suggests an approximately Euclidean metric.

Perceived color shift of a shade guide according to the change of illuminant

The perceived color of shade guide tabs is influenced by different spectral compositions of different light sources, and this can influence color matching. The purpose of this study was to determine the amount of perceived shift in color and color coordinates of a shade guide using 3 different light sources: CIE standard illuminant D65 (daylight), A (incandescent lamp), and F9 (fluorescent lamp). CIE color coordinates L*, a*, b*, chroma, and the spectral reflectance of shade tabs in a shade guide (Vitapan 3D-Master) were measured by a spectroradiometer under D65, A, and F9 simulators. Perceived color and color coordinate shifts due to the change of illuminant were determined. The influence of the type of light and shade designation of the 26 tabs on the color coordinates was analyzed by a 2-way ANOVA; correlations in the color coordinates between each corresponding pair under the 3 illuminants were determined (α=.05). All of the color coordinates were influenced by the type of illuminant and shade designation of the shade tabs (P<.001); however, each corresponding coordinate pair showed significant correlations under different illuminants (r=0.930 to 0.997, P<.01). Color differences under different illuminants were in the range of 3.1 to 9.1 ΔE units; all of these differences were perceptible (ΔE>2.6). Lightness decreased and chroma increased when the illuminant was changed from the D65 simulator to the A or F9 simulators. Perceptible shifts in the color of shade guide tabs under different ambient lighting conditions were confirmed by a spectroradiometer; these color shifts were influenced by the type of illuminant used.

확률맵 기반 유전자 알고리즘에 의한 ROI 검출

본 연구에서는 인물영상에서 입술영역을 검출하기 위한 확률맵 기반 유전자 알고리즘을 제안한다. 하나의 최적해 탐색에 사용되었던 기존 유전자 알고리즘을 수정하여 입술과 같은 영역 검출에 부합하는 다수의 해를 얻도록 적용한다. 이를 위해 공간좌표를 의미하는 염색체로 각 개체를 표현하고, 보존구간, 세대수에 따른 부분 균일교배, 비중복 선택 등의 유전연산 방법을 도입한다. 또한 HSV 칼라공간에서 HS성분에 대한 확률맵을 제안하고, 이를 적용함으로써 유전자 알고리즘의 속성인 유사 색상에 대한 적응성을 더욱 증대한다. 실험을 통하여 제안한 알고리즘의 성능을 좌우하는 주요 파라미터 분석, 종료 함수의 종료 조건 <TEX>$\beta$</TEX>의 최적값 평가 분석 그리고 교배 방법에 따른 성능 평가 결과를 분석하였으며, 입술 이외의 관심객체 변경에 따른 다른 ROI(Region Of Interest)의 검출에도 유연하게 적응할 수 있음을 관찰하였다. This paper propose a genetic method based on probability map to detect region of the lips on a natural image with the faces. The method has many solutions in order to detect regions such as the lips instead of one optimal solution of existing methods. To do this, it represents a pair of spatial coordinates as a chromosome, and introduces genetic operations like conservation interval, the number of generations and non-overlapping selection. By using the probability map of the HS in HSV color space, it increases adaptability to similar color that is a property of genetic algorithm. In our experiments, the optimal value of the important parameter <TEX>$\beta$</TEX> was analyzed, which was used as the condition of an ending function and affected performance of the proposed algorithm. Also the algorithm was analyzed on what performance it has when its mating methods are different. The results of the experiment showed that our algorithm could be flexibly adapted for detecting other ROIs.

Research on 3D Reconstruction Based on a Single Image

Aimed at the fact that most of the objects was symmetrical, we present a method reconstructing 3D model from single 2D image. At first, the angle, inclination angle and pivot angle should be established in the ternary perspective transformed matrix T, then the calibration which indicated the outline of the object can pick up the characteristic line. It resolved the host extinguishes information in accordance with the similar features of the parallel group of lines projection angle, then ensured the viewpoint situation and the object plane of symmetry, and made use of the object imagination plane of symmetry in accordance with symmetry feature through the interactive alignment specifying three pairs of the known symmetry image coordinates and the space coordinates of the corresponding points confirm the perspective transformative matrix T, then reverse prove the other space coordinates of the surface of the objects.

On Reverse-Free Codes and Permutations

A set $\mathcal{F}$ of ordered $k$-tuples of distinct elements of an $n$-set is pairwise reverse free if it does not contain two ordered $k$-tuples with the same pair of elements in the same pair of coordinates in reverse order. Let $F(n,k)$ be the maximum size of a pairwise reverse-free set. In this paper we focus on the case of 3-tuples and prove $\lim F(n,3)/\binom{n}{3}=5/4$, more exactly, $\frac{5}{24}n^3-\frac{1}{2}n^2-O(n\log n)<F(n,3)\leq\frac{5}{24}n^3-\frac{1}{2}n^2+\frac{5}{8}n$, and here equality holds when $n$ is a power of 3. Many problems remain open.

AltPS: A Structural Alignment Tool for Protein Surfaces Using Similarity of Local Atomic Environments

We have developed an alignment tool for comparing protein local surfaces (AltPS). This program enables efficient exhaustive searches of the entire protein surfaces, using a feature vector for a surface atom with 6 to 18 elements to describe the geometrical and physicochemical properties in the local environment, without referring sequence or fold homology. AltPS runs on a personal computer with the input of a pair of PDB coordinates and outputs similarity scores between identified similar surfaces, alignments of the surface atoms, and corresponding superposed coordinates, based on cluster analysis of similar surface regions. In this report, we present some results on the application of AltPS to several protein pairs with similar functions to identify similar functional sites. AltPS can be downloaded from http://d-search.atnifty.com/research.html

Home range area and shape of yellow-bellied marmots

Home range is the area that marmots use to obtain food and burrows necessary for growth, reproduction and survival. During regular censuses, the position of each marmot was recorded as a pair of coordinates from a calibrated grid overlain on a photograph of the colony site. Home range area was calculated as the product of the area of a grid square multiplied by the number of grid squares a marmot utilized. Clearly identified excursions were not included in the calculation of area. Shape was determined as the outline of the home range. The analysis included 24 years, four ages, two sexes, four colonies, four categories of residency, and whether an individual engaged in excursions. A general linear model ANOVA revealed that year (P > 0.001), age (P > 0.001), residency (P > 0.001), and colony (P > 0.001) significantly affected home range area but that sex (P = 0.373) and excursions (P = 0.312) did not. Shape was affected mainly by topography and the presence of other marmots. Area increased with age: adults < 2-year-olds < yearlings < young. Territorial males had the largest area followed by adult females whose area was larger than that of yearlings. Home range varied among colonies. Young and transients made the fewest excursions; adults, the most. Excursions were more frequent in the largest colonies. Residency was significantly affected by age, colony, sex, and excursions. Dispersers and transients were male-biased; residents were biased toward females and young.

Hamiltonian thermodynamics of charged three-dimensional dilatonic black holes

The action for a class of three-dimensional dilaton-gravity theories, with an electromagnetic Maxwell field and a cosmological constant, can be recast in a Brans-Dicke-Maxwell type action, with its free {omega} parameter. For a negative cosmological constant, these theories have static, electrically charged, and spherically symmetric black hole solutions. Those theories with well formulated asymptotics are studied through a Hamiltonian formalism, and their thermodynamical properties are found out. The theories studied are general relativity ({omega}{yields}{+-}{infinity}), a dimensionally reduced cylindrical four-dimensional general relativity theory ({omega}=0), and a theory representing a class of theories ({omega}=-3), all with a Maxwell term. The Hamiltonian formalism is set up in three dimensions through foliations on the right region of the Carter-Penrose diagram, with the bifurcation 1-sphere as the left boundary, and anti-de Sitter infinity as the right boundary. The metric functions on the foliated hypersurfaces and the radial component of the vector potential one-form are the canonical coordinates. The Hamiltonian action is written, the Hamiltonian being a sum of constraints. One finds a new action which yields an unconstrained theory with two pairs of canonical coordinates (M,P{sub M};Q,P{sub Q}), where M is the mass parameter, which for {omega}<-(3/2) and for {omega}={+-}{infinity} needs a careful renormalization, P{submore » M} is the conjugate momenta of M, Q is the charge parameter, and P{sub Q} is its conjugate momentum. The resulting Hamiltonian is a sum of boundary terms only. A quantization of the theory is performed. The Schroedinger evolution operator is constructed, the trace is taken, and the partition function of the grand canonical ensemble is obtained, where the chemical potential is the scalar electric field {phi}. Like the uncharged cases studied previously, the charged black hole entropies differ, in general, from the usual quarter of the horizon area due to the dilaton.« less