Kinematics of a 6-DOF parallel manipulator with two limbs actuated by spherical motion generators

Inspired by dual-arm-like manipulation, a novel 6-DOF parallel manipulator with two spherical-universal-revolute limbs is proposed. Compared with general 6-DOF parallel manipulators with six limbs, this new manipulator actuated by spherical motion generators has only two limbs, which brings advantages such as fewer active limbs for avoiding interference, larger reachable and orientational workspace for complex operating, more actuators integrated in active modules for decreasing installation errors and increasing compactness. In this paper, the kinematics of this novel parallel manipulator is solved and illustrated, covering its inverse and forward position analysis, workspace and singularities. The kinematic study reveals interesting features of this manipulator such as multiple working and assembly modes, small footprint and large workspace volume with high dexterity. Numerical examples of kinematic analysis are included. Practical application of the new manipulator is illustrated.

Creating versatility in Thai demonstratives

Beyond their basic function to index exophoric and endophoric referents, Thai demonstratives have a host of pragmatic functions to encode concerns regarding discourse organization, subjectivity, and intersubjectivity. Based on a detailed analysis of demonstratives used in conversation, we attempt to uncover the pattern of grammaticalization for this class of words in Thai, and to propose a mechanism that allows them to develop multiple functions. Since demonstratives are indexical signs and are qualitatively distinct from content words, we must view the grammaticalization process of demonstratives differently from that of content words. In this paper, we use the model of the joint attention triangle based on Diessel’s earlier work and the functional utterance frame based on the “attractor position” analysis for grammaticalization of nouns and verbs advanced by Bisang (1996) to analyze how exactly demonstratives come to acquire pragmatic functions.

Global Position Analysis during Official Elite Female Beach Volleyball Competition: A Pilot Study

The aim of this study was to quantify the physical demands of female beach volleyball competition with reference to player position, set, and match outcome. Twelve professional players were equipped with a 10 Hz GPS device (Minimax S4, Catapult Sports, Australia). Data collection occurred over 30 official matches, with a total of 50 sets. GPS output variables were related to position (e.g., Defenders and Blockers). Differences between players’ positions were found in Peak Player Load, the distance covered at different intensities, and acceleration and deceleration. Variations during the match were more pronounced for Defenders than for Blockers, with the former increasing the intensity of acceleration and deceleration, and decreasing the velocity of displacements and lower jumps. For Blockers, main variations occurred between the first and second set, with a reduction in velocity displacements and an increase in the intensity of jumps. Defender variables that contributed to victory were high deceleration, velocity, acceleration, and Peak Player Load. The characteristics of Blockers that contributed to victory were maximum velocity and high jumps. Female beach volleyball players seem to have different physiological requirements according to their position. The analysis of these variations throughout the game suggests that a specific player’s position output may be determined by proper and/or opponent tactical schemes.

Optimal fusion of multi-focus image: Integrating WNMF and focal point analysis

Image fusion can be used to improve the image utilization, spatial resolution and spectral resolution, which has been widely applied on medicine, remote sensing, computer vision, weather forecast and military target recognition. The goal of image fusion is to reduce the uncertainty and redundancy of the output and increase the reliability of the image on the basis of the maximum combination of relevant information. In this paper, a multi-focus image fusion algorithm based on WNMF and Focal point position analysis is proposed to improve the image fusion method based on nonnegative matrix factorization. In the imaging process, the Gaussian function is used to approximate the point spread function in the optical system. Then calculate the difference between the original image and the approximate point spread function and get the weighted matrix [Formula: see text]. Finally, we apply the weighted nonnegative matrix algorithm to image fusion, and the new fusion image with clear parts is obtained. Experimental results show that the multi-focus image fusion algorithm based on WNMF and Focal point position analysis (MFWF) is better.

TURKMEN NATIONAL CULTURAL CENTER OF THE REPUBLIC OF KARAKALPAKSTAN

Interethnic harmony is one of the priority directions of every state policy, and all conditions havebeen created for the representatives of every nation living in our country to find their place in society. In studying the sphere of interethnic relations, it is of great importance to study the social role of each ethnic group, the activities of nationaland cultural centers.The article examines the role of the Turkmen nation in the national composition of the Republic of Karakalpakstan during the years of independence, its geographical position, analysis by year, the activities of the Turkmen National Cultural Center, the role of the center in strengthening interethnic relations

A unified analytical parametric method for kinematic analysis of planar mechanisms

This paper describes a method for unified parametric kinematic analysis of those planar mechanisms whose geometry can be defined with a set of independent vectorial loops, i.e. solvable independently; this covers a wide range of planar mechanisms. The method is developed by employing the well-known vectorial illustration, and vectorial-loop equations solved with the aid of complex polar algebra leading to a total of only nine unified/generic one-unknown parametric equations consisting of five equations for position analysis and two equations for velocity and acceleration analysis each. Then, the kinematics of joints and mass centers are manifested as resultants of a few known vectors. This method is needless of relative-velocities, relative-accelerations, instantaneous centers of rotation and Kennedy’s Theorem dominantly used in the literature, especially textbooks. The efficiency of the method is demonstrated by its application to a complex mechanism through only eight unified equations, and simultaneously compared to the solution using the textbook common (Raven’s) method which required the derivation of 67 extra equations to get the same results. This reveals the fact that the method is not only a powerful tool for mechanical designers but a most powerful and efficient method for teaching and learning the kinematics of planar mechanisms.