External Labelings with Polyline Leaders

The interaction of solids with multiple electromagnetic fields is of great importance in quantum electronics. In this paper the behavior of the heat transfer in a solid irradiated by multiple laser beams is investigated. The directions of laser beams propagation are supposed to be along Cartesian coordinate axes. The spatial distribution of laser beams is supposed to be Gaussian. The model is valid for any laser-solid system whose interaction can be described by the Beer law. Calculations are performed using the integral transform method^1,2. The spatial and temporal temperature field distributions are plotted considering a real situation in which ZnSe samples are continuously irradiated with one, respectively three CO₂ laser beams.

The paper discusses the problem on a rigid flat-based die forced into a half-strip. The material of the half-strip, whose semiinfinite sides are fixed, is orthotropic; the principal axes of anisotropy coincide with the Cartesian coordinate axes. Friction between the die and the half-strip is taken into account. The problem is solved by an asymptotic method developed by the authors. Some numerical results are presented

Van Trier and Symes (1991) introduced a simple method for calculating first-arrival traveltimes based on recasting the eikonal equation in flux-conservative form. In that form, the eikonal equation can be efficiently solved using the first-order Engquist-Osher scheme (Engquist and Osher, 1980). Dellinger (1991b) later showed how to generalize their method to allow for transverse isotropy aligned with Cartesian coordinate axes. Unfortunately, the method does not easily generalize to allow general anisotropy, high-order numerical accuracy, or threedimensional propagation.

Stress concentration factors around a circular hole in two fiber reinforced materials under large deformations

First order perturbation considerations are applied to general orthoaxial chromophores. These contain monatomic or linear ligands which are so positioned around the central ion that Cartesian coordinate axes can be placed through the ligands. The zero order functions used are the orbitals of the partially filled shell which are proper basis functions of the regular octahedron and can be thought of as general molecular orbitals of a particular regularly octahedral chromophore. Certain degeneracies not demanded by the proper chromophoric symmetry are rationalized in terms of the holohedrized symmetry, which also determines the number of parameters required for the full parametrization. All the results obtained are, apart from a minor correction given explicitly, formally equivalent to those obtained earlier using the angular overlap model and the electrostatic model. The extra correction required in the present more general treatment is probably unimportant in view of the approximations involved, in particular that of using a basis restricted to five orbitals.

The work is devoted to the implementation of a scientific and methodological justification for the application of fractal series theory to solve one of the key tasks of field development ‒ an integrated assessment of the effectiveness of flooding oil reservoirs using quantitative data to determine the effectiveness of well interactions. The object of research in this work is the deposits of carbonate reservoirs of the South Tatar arch, which have been in operation for a long time and for which a significant amount of geological and field information has been accumulated. As part of the application of the modified Hearst indicator calculation system in Cartesian coordinate axes with a logarithmic scale, the dynamics of changes in technological indicators for producing and injection wells were interpreted according to two different scenarios, the modeling of which provides a detailed picture of the change in the fluid motion vector in the borehole-reservoir system. The calculations made it possible to establish intervals with the most effective filtration of the fluid and identify patterns of change in the Hearst index based on the qualitative characteristics of flooding. It is concluded that it is necessary to take into account the deviation of the values of the coordinates of the curves for producing and injection wells from each other in the planning and design of both additional field studies and measures aimed at optimizing the processes of oil displacement by water. Keywords: deposits of carbonate reservoirs of the South Tatar arch; Hearst index; theory of fractal series; processing of geological and field data; assessment of the degree of mutual influence of wells.

Since its introduction in the early 1980s, the concept of a "preferred direction" for neuronal discharge has proven to be a powerful means of studying motor areas of the brain. In the current paper, we introduce the concept of a "muscle-space"-preferred direction (PD(M)) that is analogous to the familiar hand-space-preferred direction (PD(H)). PD(M) reflects the similarity between the discharge of a given neuron and the activity of each muscle in much the way that PD(H) reflects the similarity of discharge with motion along each of the three Cartesian coordinate axes. We used PD(M) to analyze the data recorded from neurons in the primary motor cortex (M1) of three different monkeys. The monkeys performed center-out movements within two different cubical workspaces centered either to the left or right of the monkey's shoulder while we simultaneously recorded neuronal discharge, muscle activity, and limb orientation. We calculated preferred directions in both hand space and muscle space, and computed the angles between these vectors under a variety of conditions. PDs for different neurons were broadly distributed throughout both hand space and muscle space, but the muscle-space vectors appeared to form clusters of functionally similar neurons. In general, repeated estimates of PD(M) were more stable over time than were similar estimates of PD(H). Likewise, there was less change in PD(M) than in PD(H) for data recorded from the two different workspaces. However, although a majority of neurons had this muscle-like property, a significant minority was more stable in Cartesian hand space, reflecting a heterogeneity of function within M1.

This paper presents stiffness analysis of hexaslides, a class of parallel manipulators with six constant length legs, the base joints of which move along six distinct rail-axes. In the design of hexaslides for machine tool applications, stiffness as well as its variation within the workspace is important. The stiffness of any parallel kinematic machine and, thus, the accuracy depends on the pose of the tool platform. A stiffness model of a generic hexaslide is developed here considering the flexibilities in both the actuator and the legs of the hexaslide. The methodology adopted is based on the concept of the determination of stiffness of a group of serially connected linear springs. Based on the proposed model, the average stiffness and its variation along and about the Cartesian coordinate axes offered by three typical hexaslides, having the same foot print size, are estimated and compared. Other typical performance indices, i.e. workspace volume, workspace volume index (ratio of workspace volume to machine size), global dexterity index and global stiffness index, are also compared.

Lower back pain is prevalent in society and manual lifting has been linked as one potential cause of these types of injuries. Therefore, the 3dLift biomechanical model was developed in this research with the goal of quantitatively analyzing lifting motions. The model divided the body into fifteen segments that were connected by fourteen anatomical joints. During experimental trials, a volunteer subject lifted an object using four different lifting combinations; symmetric leglifts, asymmetric leglifts, symmetric backlifts, and asymmetric backlifts. In order to individualize the 3dLift model, anthropometric parameters were estimated using measurements taken on the subject. During the lifting trials, the subject wore reflective markers placed on anatomical landmarks, the motions of which were tracked by five video cameras. The subject also stood with each foot on a separate force platform that was used to determine ground reaction forces and centers of pressure. Signal processing methods were utilized to predict the marker positions that were obscured during the lifting trials, and digital filtering was implemented to attenuate noise in the data. After reducing the experimental errors, the segment coordinate axes, Cardan angles, joint center positions, and mass center positions were calculated. The changes in the segment orientations with respect to time were then analyzed to determine the three-dimensional kinematics of the segments. Anthropometric, video, and force platform information were combined in equations of motion that were derived to predict the forces and moments occurring at the joints during the lifting motions. A lower body formulation was developed that started with the measured ground reactions at the feet and proceeded through the segments to the TlO/Tl 1 intervertebral joint. Similarly, an upper body formulation was derived that began with a known lifted load at the hands and continued through the segments to the same TlO/Tl 1 intervertebral joint. While predicting joint forces and moments, the two formulations also served as a means of validating the SdLift model by comparing the results at the TlO/Tl 1 joint. While there is much work yet to be done in this research area, the 3dLift model takes the first steps by developing a systematic methodology for studying lifting motions.