Pair Of Coordinates Research Articles

Color and translucency of milled polymethyl methacrylate crowns on non–tooth-colored interim abutments with different surface treatments

Statement of problemThe interim rehabilitation of implants has become a necessity, particularly for those placed in the esthetic regions. However, the optical properties of computer-aided design and computer-aided manufacturing (CAD-CAM) polymethyl methacrylate (PMMA) crowns on interim abutments with different surface treatments are unclear. PurposeThe purpose of this in vitro study was to investigate the color and translucency of CAD-CAM PMMA crowns when different surface treatments were used on titanium interim abutments. Material and methodsA maxillary dentate stone cast with a narrow-diameter implant analog at the left lateral incisor site was used. Three titanium interim abutments (blue) were divided into 3 groups according to the surface treatment they received: control (steam cleaning), opaqued (120-μm Al2O3 airborne-particle abrasion and opaque application), and airborne-particle abraded (120-μm Al2O3). Thirty PMMA crowns (A2 shade) were milled (n=10). The color coordinates of the crown-interim abutment pairs and a shade tab (A2) were measured by using a colorimeter. The color differences (ΔE00) between the crowns and the shade tab and the relative translucency parameter (RTP) values of the crowns were calculated by using the CIEDE2000 formula. One-way ANOVA was used to analyze the ΔE00 and RTP values with subsequent Tukey honestly significant difference tests (α=.05). ResultsThe abutment surface treatment significantly affected the ΔE00 of interim crowns from the shade tab (P<.001), but no significant effect was found on RTP (P=.26). The control group had the highest ΔE00 from the shade tab (P≤.011). No significant difference (P=.14) was found between the opaqued and the ΔE00 of the airborne-particle abraded groups from the shade tab. ConclusionsThe surface treatments of interim abutments affected the color of CAD-CAM PMMA crowns, which differed from that of the shade tab. The color of crowns on opaqued or airborne-particle abraded interim abutments was closer to the color of the shade tab. Abutment surface treatments did not affect the translucency of crown-interim abutment pairs.

Prepareforleap: An automated tool for fast PDB-to-parameter generation.

Setting up molecular dynamics simulations from experimentally determined structures is often complicated by a variety of factors, particularly the inclusion of carbohydrates, since these have several anomer types which can be linked in a variety of ways. Here we present a stand-alone tool implemented in the widely-used software CPPTRAJ that can be used to automate building structures and generating a "ready to run" parameter and coordinate file pair. This tool automatically identifies carbohydrate anomer type, configuration, linkage, and functional groups, and performs topology modifications (e.g., renaming residue/atom names) required to build the final system using state of the art GLYCAM force field parameters. It will also generate the necessary commands for bonding carbohydrates and creating any disulfide bonds.

Critical Field Theories with OSp(1|2M) Symmetry

In the paper [L. Fei etal., J. High Energy Phys. 09 (2015) 076JHEPFG1029-847910.1007/JHEP09(2015)076] a cubic field theory of a scalar field σ and two anticommuting scalar fields, θ and θ[over ¯], was formulated. In 6-ε dimensions it has a weakly coupled fixed point with imaginary cubic couplings where the symmetry is enhanced to the supergroup OSp(1|2). This theory may be viewed as a "UV completion" in 2<d<6 of the nonlinear sigma model with hyperbolic target space H^{0|2} described by a pair of intrinsic anticommuting coordinates. It also describes the q→0 limit of the critical q-state Potts model, which is equivalent to the statistical mechanics of spanning forests on a graph. In this Letter we generalize these results to a class of OSp(1|2M) symmetric field theories whose upper critical dimensions are d_{c}(M)=2[(2M+1)/(2M-1)]. They contain 2M anticommuting scalar fields, θ^{i}, θ[over ¯]^{i}, and one commuting one, with interaction g(σ^{2}+2θ^{i}θ[over ¯]^{i})^{(2M+1)/2}. Ind_{c}(M)-ε dimensions, we find a weakly coupled IR fixed point at an imaginary value of g. We propose that these critical theories are the UV completions of the sigma models with fermionic hyperbolic target spaces H^{0|2M}. Of particular interest is the quintic field theory with OSp(1|4) symmetry, whose upper critical dimension is 10/3. Using this theory, we make a prediction for the critical behavior of the OSp(1|4) lattice system in three dimensions.

Uncovering spatial heterogeneity in real estate prices via combined hierarchical linear model and geographically weighted regression

Spatial heterogeneity is important for exploring data relationships between real estate price and its influential factors. The geographically weighted regression (GWR) technique has been frequently adopted for this purpose. In this study, we collected a second-hand real estate house price data set of Wuhan, in which each property is located the same as the community it belongs to. Thus, this data set possesses a typical characteristic, that is, dozens or even hundreds of observations could be allocated to one pair of coordinates, but vary in their attributes. This specific feature might lead to serious problems with bandwidth optimisations and coefficient estimates for calibrating the GWR model. We then proposed an extension by combining the hierarchical linear model (HLM) and GWR, namely HLM-GWR to cope with these problems. Results show that the HLM-GWR performs much better than the conventional GWR and HLM technique in terms of bandwidth optimisation, coefficient estimates. With a controlled simulation test, we again validated the advantage of the HLM-GWR model in comparison to both the HLM and GWR in handling this specific scenario. Overall, HLM-GWR is workable and should be recommended in this case or other scenarios with observations of similar spatial distributions.

A unified approach for automated segmentation of pupil and iris in on-axis images

We propose a unified approach for the automatic and accurate segmentation of the pupil and iris from on-axis grayscale eye images. The segmentation of pupil and iris is achieved with Basis-spline-based active contour and circular active contour, respectively. The circular active contour shape template has three free parameters, i.e., a pair of center coordinates and the radius. Basis-spline has M knots in the shape template and five free parameters i.e., a pair of center coordinates, scaling in the horizontal and vertical directions, and the rotation angle. The segmentation of the region of interest is done by minimization of the local energy function. Optimization of the local energy function of circular and Basis-spline-based active contour is carried out using gradient descent technique and Green’s theorem. To achieve the segmentation of iris boundary, the circular active contour method is combined with our novel occlusion removal algorithm. This helps in removing eyelid and eyelash occlusions for accurate iris segmentation. Automatic localization of the pupil is achieved by the sum of absolute difference method. The proposed algorithm is validated on three publicly available databases: IIT Delhi Iris, CASIA Iris Interval V3, and CASIA Iris Interval V4 databases consisting of 7518 grayscale iris images in total. For the segmentation of pupil from the aforementioned databases, we attained a Dice index of 0.971, 0.950, and 0.960, respectively, and for the segmentation of iris, we attained a Dice index of 0.905, 0.898, and 0.900, respectively. An exploratory data analysis was then done to visualize the distribution of the performance parameters throughout the databases. The segmentation performance of the proposed algorithm is on par with that of the reported state-of-the-art algorithms.

GPS2space: An Open-source Python Library for Spatial Measure Extraction from GPS Data.

Global Positioning System (GPS) data have become one of the routine data streams collected by wearable devices, cell phones, and social media platforms in this digital age. Such data provide research opportunities in that they may provide contextual information to elucidate where, when, and why individuals engage in and sustain particular behavioral patterns. However, raw GPS data consisting of densely sampled time series of latitude and longitude coordinate pairs do not readily convey meaningful information concerning intra-individual dynamics and inter-individual differences; substantial data processing is required. Raw GPS data need to be integrated into a Geographic Information System (GIS) and analyzed, from which the mobility and activity patterns of individuals can be derived, a process that is unfamiliar to many behavioral scientists. In this tutorial article, we introduced GPS2space, a free and open-source Python library that we developed to facilitate the processing of GPS data, integration with GIS to derive distances from landmarks of interest, as well as extraction of two spatial features: activity space of individuals and shared space between individuals, such as members of the same family. We demonstrated functions available in the library using data from the Colorado Online Twin Study to explore seasonal and age-related changes in individuals' activity space and twin siblings' shared space, as well as gender, zygosity and baseline age-related differences in their initial levels and/or changes over time. We concluded with discussions of other potential usages, caveats, and future developments of GPS2space.

Quadratic residue codes, rank three groups and PBIBDs

The automorphism group of the Zetterberg code Z of length 17 (also a quadratic residue code) is a rank three group whose orbits on the coordinate pairs determine two strongly regular graphs equivalent to the Paley graph attached to the prime 17. As a consequence, codewords of a given weight of Z are the characteristic vectors of the blocks of a PBIBD with two associate classes of cyclic type. More generally, this construction of PBIBDs is extended to quadratic residue codes of length \(\equiv 1 \pmod {8},\) to the adjacency codes of triangular and lattice graphs, and to the adjacency codes of various rank three graphs. A remarkable fact is the existence of 2-designs held by the quadratic residue code of length 41 for code weights 9 and 10.

Improving the Performance of Mode-Based Sound Propagation Models by Using Perturbation Formulae for Eigenvalues and Eigenfunctions

Numerous sound propagation models in underwater acoustics are based on the representation of a sound field in the form of a decomposition over normal modes. In the framework of such models, the calculation of the field in a range-dependent waveguide (as well as in the case of 3D problems) requires the computation of normal modes for every point within the area of interest (that is, for each pair of horizontal coordinates x,y). This procedure is often responsible for the lion’s share of total computational cost of the field simulation. In this study, we present formulae for perturbation of eigenvalues and eigenfunctions of normal modes under the water depth variations in a shallow-water waveguide. These formulae can reduce the total number of mode computation instances required for a field calculation by a factor of 5–10. We also discuss how these formulae can be used in a combination with a wide-angle mode parabolic equation. The accuracy of such combined model is validated in a series of numerical examples.

Double null coordinates for Kerr spacetime

We present a definition for a pair of null coordinates that are naturally adapted to the horizons and future null infinity of Kerr spacetime, and that are generated by the center-of-mass sections at future null infinity. They are a smooth, round family of null hypersurfaces which foliate the Kerr spacetime in an outgoing and an ingoing sense, respectively, and they have a regular extension across the horizons. Because of Kerr's peculiar geometry, the construction involves a nonlinear differential equation for a scalar function related to Carter's constant, whose solution cannot be expressed in terms of simple analytic functions. We present the numerical solution of this scalar for a particular choice of the geometrical parameters. In this setting, there naturally appears a two-dimensional spacelike family of round surfaces ${S}_{{r}_{s}}$ that are parametrized by ${r}_{s}$, which are the intersections of both null coordinates, where ${r}_{s}$ can be thought of as the tortoise coordinate extension for the Kerr spacetime. The ${S}_{{r}_{s}}$ surfaces are axially symmetric, but they have an $(r,\ensuremath{\theta})$ dependence in Boyer-Lindquist coordinates. They can also be characterized in a complete geometrical way by their Gaussian and extrinsic curvature scalars, which we were able to compute by the use of Geroch-Held-Penrose formalism. We compare our definition with other previous attempts in the literature, and we show that all of them have divergent behavior at the axis of symmetry. Thus, our construction presents the first double null coordinate system which makes possible computations over all of the Kerr spacetime.

DATA REDUCTION BY THE HAAR FUNCTION: A CASE STUDY OF THE PHILLIPS CURVE

The unorthodox estimation procedure, which Phillips (1958) adopted in his original paper, is examined using the Haar wavelet filter. The application of the Haar wavelet transform to Phillips’ original data shows that Phillips’ six pairs of mean coordinates display a striking similarity with the Haar scaling coefficients that represent averages with a period greater than 16 years. This is consistent with Desai’s (1975) intuition on the interpretation of the Phillips Curve. We show that the choice of sorting observations by ascending values of the unemployment rate is crucial for reaching the goal of estimating the eye-catching nonlinear hyperbolic shape of the wage–unemployment relationship that would be otherwise linear. Interestingly, the Haar filter can account not only for the facts characterizing the Phillips’ relationship up to the early 1960s but also for two important facts mostly debated among policymakers: the downward shift of the Phillips Curve and its flattening over time.

Creating open source composite geocoders: Pitfalls and opportunities

AbstractGeocoding, the process of converting a street address into a pair of coordinates that facilitate mapping, is a perennial challenge for researchers. Both technical and practical barriers exist to geocoding itself and creating reproducible workflows that string multiple geocoders together (so‐called “composite” geocoders). This article presents a suite of open‐source tools designed to standardize American addresses and geocode them. These tools culminate in a composite geocoder for the city of St. Louis, Missouri, which serves as a proof‐of‐concept for developing sophisticated geocoding processes. We test this geocoder on a data set of 1,822 homicides for St. Louis between 2008 and 2018, comparing the results of our tools to a range of commercial providers. We find varying levels of efficiency and accuracy across the available commercial platforms and demonstrate that our in‐house tools provide high positional accuracy with significant efficiency increases.

O uso das geotecnologias como ferramentas de ensino na educação básica da escola Prof.º Virgílio Libonati, Belém, Pará, Brasil

As geotecnologias estão cada vez mais acessíveis e isto se deve aos softwares livres e gratuitos estarem sendo progressivamente produzidos e difundidos, bem como também a adequação da linguagem destes softwares que vem sendo demandada, de forma a possibilitar o acesso a um público cada vez mais amplo. O objetivo é diagnosticar a utilização das geotecnologias, como instrumento de ensino da Geografia. O referido estudo foi realizado em loco com alunos de 6º ano na escola pública de âmbito Estadual Prof.º Virgílio Libonati localizada na região metropolitana de Belém do Pará, cujo o par de coordenadas para acesso é 01°27'9.73" latitude Sul e 48°26'38.22" longitude Oeste. A metodologia incluiu a aplicação de questionários após uma palestra com a finalidade de melhor entendimento sobre a cartografia, o meio ambiente e utilidades computacionais. O público algo foram 20 (Vinte) alunos na faixa etária de 11 anos pertencente ao turno vespertino. Essa abordagem destacou a importância das geotecnologias no cotidiano escolar procurando tornar mais dinâmico e eficaz os conceitos geográficos durantes o processo de ensino-aprendizagem.

JEDi: java essential dynamics inspector \u2014 a molecular trajectory analysis toolkit

BackgroundPrincipal component analysis (PCA) is commonly applied to the atomic trajectories of biopolymers to extract essential dynamics that describe biologically relevant motions. Although application of PCA is straightforward, specialized software to facilitate workflows and analysis of molecular dynamics simulation data to fully harness the power of PCA is lacking. The Java Essential Dynamics inspector (JEDi) software is a major upgrade from the previous JED software.ResultsEmploying multi-threading, JEDi features a user-friendly interface to control rapid workflows for interrogating conformational motions of biopolymers at various spatial resolutions and within subregions, including multiple chain proteins. JEDi has options for Cartesian-based coordinates (cPCA) and internal distance pair coordinates (dpPCA) to construct covariance (Q), correlation (R), and partial correlation (P) matrices. Shrinkage and outlier thresholding are implemented for the accurate estimation of covariance. The effect of rare events is quantified using outlier and inlier filters. Applying sparsity thresholds in statistical models identifies latent correlated motions. Within a hierarchical approach, small-scale atomic motion is first calculated with a separate local cPCA calculation per residue to obtain eigenresidues. Then PCA on the eigenresidues yields rapid and accurate description of large-scale motions. Local cPCA on all residue pairs creates a map of all residue-residue dynamical couplings. Additionally, kernel PCA is implemented. JEDi output gives high quality PNG images by default, with options for text files that include aligned coordinates, several metrics that quantify mobility, PCA modes with their eigenvalues, and displacement vector projections onto the top principal modes. JEDi provides PyMol scripts together with PDB files to visualize individual cPCA modes and the essential dynamics occurring within user-selected time scales. Subspace comparisons performed on the most relevant eigenvectors using several statistical metrics quantify similarity/overlap of high dimensional vector spaces. Free energy landscapes are available for both cPCA and dpPCA.ConclusionJEDi is a convenient toolkit that applies best practices in multivariate statistics for comparative studies on the essential dynamics of similar biopolymers. JEDi helps identify functional mechanisms through many integrated tools and visual aids for inspecting and quantifying similarity/differences in mobility and dynamic correlations.

On Chamfer Distances on the Square and Body-Centered Cubic Grids: An Operational Research Approach

Linear programming is used to solve optimization problems. Thus, finding a shortest path in a grid is a good target to apply linear programming. In this paper, specific bipartite grids, the square and the body-centered cubic grids are studied. The former is represented as a “diagonal square grid” having points with pairs of either even or pairs of odd coordinates (highlighting the bipartite feature). Therefore, a straightforward generalization of the representation describes the body-centered cubic grid in 3D. We use chamfer paths and chamfer distances in these grids; therefore, weights for the steps between the closest neighbors and steps between the closest same type points are fixed, and depending on the weights, various paths could be the shortest one. The vectors of the various neighbors form a basis if they are independent, and their number is the same as the dimension of the space studied. Depending on the relation of the weights, various bases could give the optimal solution and various steps are used in the shortest paths. This operational research approach determines the optimal paths as basic feasible solutions of a linear programming problem. A directed graph is given containing the feasible bases as nodes and arcs with conditions on the used weights such that the simplex method may step from one feasible basis to another one. Thus, the optimal bases can be determined, and they are summarized in two theorems. If the optimal solution is not integer, then the Gomory cut is applied and the integer optimal solution is reached after only one Gomory iteration. Chamfer distances are frequently used in image processing and analysis as well as graphics-related subjects. The body-centered cubic grid, which is well-known in solid state physics, material science, and crystallography, has various applications in imaging and graphics since less samples are needed to represent the signal in the same quality than on the cubic grid. Moreover, the body-centered cubic grid has also a topological advantage over the cubic grid, namely, the neighbor Voronoi cells always share a full face.

Image Fusion-The Pioneering Technique for Real-Time Image Processing Applications

An image is a two-dimensional function that is expressed through spatial coordinates X, Y. At any pair of coordinates (x, y), the amplitude of a point is called the intensity of that pixel. Digital Image comprises a predictable number of components, each of which has a precise value at a given region. Those components are called pixels. Image Fusion is a phenomenon of transforming data from two or more images of a scenario into a single, more descriptive image taken than both of the input images, and is more appropriate for information processing. Image Fusion (IF) has been utilized in numerous application regions/areas. Remote Sensing Satellites (RSS) produce different images based on their sensory characteristics. Among those images, Panchromatic (PAN) and Multi-Spectral (MS) images are widely used in Satellite Image Fusion (SIF). The Image Fusion (IF) techniques are broadly classified as methods for the Spatial and Frequency domains. Wavelet Fusion Techniques (WFT) based on the Frequency-Domain (FD) are having applications in medical, space, and military applications. This literature delivers a study of some of the Image Fusion (IF) techniques. Remote Sensing Image (RSI) and Data Fusion (DF) seeks to merge the data acquired from sensors installed on satellites, airborne platforms, and ground-based sensors with specific spatial, spectral and temporal resolutions to produce merged data containing more accurate information than is found in each of the individual data sources.

The Influence of Antenna Height on the Measurement of Collective Variables Using an Ultra-Wide Band Based Local Positioning System in Team Sports.

Ultra-wide band (UWB) based local positioning systems (LPS) are based on devices and a portable antenna set. The optimal installation height of the antennae is crucial to ensure data accuracy. Collective variables are metrics that consider at least two pairs of coordinates, which may lead to lower precision than an individual one. Therefore, the aim of this study was to compare the influence of antenna height with collective metrics using a UWB (i.e., IMU; WIMU PRO™, RealTrack Systems, Almeria, Spain) based LPS. Data acquisition was carried out in a basketball court measuring 28 × 15 m. Five devices were used; one of which was carried by a healthy and well-trained athlete (age: 38 years, mass: 76.34 kg, height 1.70 m), while each of the remaining four was positioned on a tripod in one of the four corners of the court. Four kinds of variables were extracted: (1) static distances, (2) dynamic distances, (3) static areas and (4) dynamic areas in all antenna installation modes of 0.15, 1.30 and 2.00 m. The results showed that the antenna of 1.30 m provided better accuracy for all measures (% difference range from −0.94 to 1.17%) followed by the antenna of 2.00 m (% difference range from −2.50 to 2.15%), with the antenna of 0.15 m providing the worst accuracy level (% difference range from −1.05 to 3.28%). Overall, the measurements of distance metrics showed greater accuracy than area metrics (distance % difference range from −0.85 to 2.81% and area % difference range from −2.50 to 3.28). In conclusion, the height of the antennae in basketball courts should be similar to the height at which the devices are attached to a player’s upper back. However, as the precision is sensitive to the magnitude of the measure, further studies should assess the effects of the relative height of antennae in team sports with greater playing spaces.

Integer Programming, Constraint Programming, and Hybrid Decomposition Approaches to Discretizable Distance Geometry Problems

Given an integer dimension K and a simple, undirected graph G with positive edge weights, the Distance Geometry Problem (DGP) aims to find a realization function mapping each vertex to a coordinate in [Formula: see text] such that the distance between pairs of vertex coordinates is equal to the corresponding edge weights in G. The so-called discretization assumptions reduce the search space of the realization to a finite discrete one, which can be explored via the branch-and-prune (BP) algorithm. Given a discretization vertex order in G, the BP algorithm constructs a binary tree where the nodes at a layer provide all possible coordinates of the vertex corresponding to that layer. The focus of this paper is on finding optimal BP trees for a class of discretizable DGPs. More specifically, we aim to find a discretization vertex order in G that yields a BP tree with the least number of branches. We propose an integer programming formulation and three constraint programming formulations that all significantly outperform the state-of-the-art cutting-plane algorithm for this problem. Moreover, motivated by the difficulty in solving instances with a large and low-density input graph, we develop two hybrid decomposition algorithms, strengthened by a set of valid inequalities, which further improve the solvability of the problem. Summary of Contribution: We present a new model to solve a combinatorial optimization problem on graphs, MIN DOUBLE, which comes from the highly active area of distance geometry and has applications in a wide variety of fields. We use integer programming (IP) and present the first constraint programming (CP) models and hybrid decomposition methods, implemented as a branch-and-cut procedure, for MIN DOUBLE. Through an extensive computational study, we show that our approaches advance the state of the art for MIN DOUBLE. We accomplish this by not only combining generic techniques from IP and CP but also exploring the structure of the problem in developing valid inequalities and variable fixing rules. Our methods significantly improve the solvability of MIN DOUBLE, which we believe can also provide insights for tackling other problem classes and applications.

A Probabilistic Approach to Address Data Uncertainty in Regionalization

Spatial data regularly suffer from error and uncertainty, ranging from poorly georeferenced coordinate pairs to sampling error associated with American Community Survey data. Geographic information systems can amplify and propagate error and uncertainty through the abstraction and representation of spatial data, as can the manipulation, processing, and analysis of spatial data using exploratory and confirmatory statistical techniques. The purpose of this article is to explore and address uncertainty in regionalization, a fundamental spatial analytical method that aggregates spatial units (e.g., tracts) into a set of contiguous regions for strategic purposes, including school districting, habitat areas, and the like. Specifically, we develop a new regionalization method, the uncertain‐max‐p‐regions problem that explicitly incorporates attribute uncertainty and allows its impacts to be evaluated with a degree of statistical certainty. We also detail an efficient solution approach for dealing the problem. The results suggest that the developed problem can out‐perform existing regionalization approaches and that the addition of a measure of statistical confidence can help to facilitate more clarity in planning and policy decisions.

Intraoperative Computed Tomography for Registration of Stereotactic Frame in Frame-Based Deep Brain Stimulation.

Deep brain stimulation (DBS) electrode placement utilizing a frame-based technique requires registration of the stereotactic frame with computed tomography (CT) or magnetic resonance (MR) imaging. This traditionally has been accomplished with a conventional CT scanner. In recent years, intraoperative CT has become more prevalent. To compare the coordinates obtained with intraoperative CT and conventional CT for registration of the stereotactic frame for DBS. Patients undergoing DBS electrode placement between 2015 and 2017, who underwent both conventional and intraoperative CT for registration of the stereotactic frame, were included for analysis. The coordinates for the stereotactic target, anterior commissure, and posterior commissure for each CT method were recorded. The mean, maximum, minimum, and standard deviation of the absolute difference for each of the paired coordinates was calculated. Paired t-tests were performed to test for statistical significance of the difference. The directional difference as well as the vector error between the paired coordinates was also calculated. The mean absolute difference between conventional and intraoperative CT for the coordinate pairs was less than 0.279 mm or 0.211 degrees for all coordinate pairs analyzed. This was not statistically significant for any of the coordinate pairs. Moreover, the maximum absolute difference between all coordinate pairs was 1.04 mm. Intraoperative CT imaging provides stereotactic frame registration coordinates that are similar to those obtained by a standard CT scanner. This may save time and hospital resources by obviating the need for the patient to go to the radiology department for a CT scan.

Analisis Penentuan Konstanta Pengendali PID Menggunakan Garis Singgung Metode Ziegler-Nichols I pada Kurva Tanggapan Keluaran Plant

The purpose of this study is to determine the PID controller constant using the Ziegler-Nichols type 1 method. This method applies the tangent-line position to the plant response curve to obtain the PID time constant which then obtains the PID controller constants.To get tangents line, a simulation of plant output responses in the matlab program is performed, from the output response curves plotted coordinate points ranging from 10% to 90% steady-state conditions in order to obtain the time and amplitude pair [x; y]. The coordinate pairs taken were 40% -60%, 30-70%, 20% -80% and 10% -90% steady-state conditions with the coordinat pair passing 50% coordinates of steady-state conditions.PID controller output response results to the constant excitation DC motor plant and AVR plant has a stable output response, control of the rise-time constant excitation DC motor and settling-time decreases so as to accelerate the plant to steady-state conditions, control of the AVR accelerates the plant reaches steady-state and decreases the amplitude of the overshoot and then oscillation period, and the best tangent-line coordinates for the PID controller output response are 20% -80%.