This investigation is devoted to the construction of a robot trajectory using a ruled surface. Transition relations among surface trihedron, tool trihedron, generator trihedron, natural trihedron and also Darboux vectors for each trihedron are given. Then, the curvature theory of ruled surface under investigation is applied to determine the differential properties of a robot end effector motion. This information is then used to characterize the linear motion of the tool center point and the angular motion of the tool frame of the robot end effector for the trajectory planning. The differential motion properties of the tool frame and the TCP point, based on the curvature theory of a ruled surface, using the relationships between the four frames of reference are studied

Radon, a naturally occurring radioactive noble gas, is the main source of the natural radiation that is received by the population. It derives from the traces of radium in rocks and can diffuse directly or as solution in water to the earth’s surface. Measurements of 222Rn concentration in a total of 21 water samples collected from Buraydah municipal water network investigated. The concentrations of 222Rn were measured by g-ray spectrometry using HPGe detector and radon detector RAD7 H2O techniques. The radon activity concentration is determined by taking the weighted average of the concentrations derived from g-ray lines associated with 214Pb and 214Bi decay. It was found that the concentration of 222Rn ranged from 1.79 ± 0.5 to 9.28 ± 1.17 Bq/l. These values are below 11.1 Bq/l the maximum contamination level recommended from the United States Environmental Protection Agency.

Shape-memory alloys (SMAs) are unique class of metal alloys that after a large deformation can, on heating, recover their original shape. Its non-linear behavior and thermal dependence attracted many researchers, engineers, and designers to choose the right material for proper applications in many fields of industry. The most commonly used material is nitinol (NiTi). Nitinol is highly biocompatible and has suitable properties for use in orthopaedic implants. Due to Nitinol's unique properties it has seen a large demand for use in less invasive medical devices. Nitinol tubing is commonly used in catheters, stents, superelastic needles and in devices for reconnecting the intestine after removing the pathology. Nitinol has been increasingly utilized in a variety of medical devices, actuators and robotic industries, nuclear reactors, in radiation environment, nuclear industry and other applications. During service in nuclear reactors, nitinol is exposed to many types of radiations which may affect its properties and structure. A comprehensive collection of previous reports on the effects of ion implantation of different energetic massive species: He+, B+, C+, N+, Ar+, Xe+, Ti+2, Ni+2, Cu+2 and Au+3 on nitinol properties are given. I hope this will be a useful and helpful guide to researchers and engineers working in this field.

This work is devoted to the study of modified Laguerre matrix polynomials. Hypergeometric matrix function representations, integral representation, and an explicit expression for the modified Laguerre matrix polynomials are investigated. Finally, identities for power series for the modified Laguerre matrix polynomials are derived.

The main goal of the research was to mesure the Radon (222Rn) concentration at indoor workplaces in different Colleges of Princess Nourah Bint Abdualrahman University (PNU), North of Riyadh, KSA, to estimate the effective dose to the worker from 222Rn and its progeny. Measuerments were carried out for 105 workplaces by using a passive integrating ionization system with an E-perm® Electret ion champer technique. Radon concentrations measured in ground, first and second floors of workplaces. Also, the measurements have done in Winter and Summer seasons. For all measurements, Radon concentrations followed a log-normal distribution with an arithmetic mean of 27.86 ± 4.39 Bq/m3 . The effective dose rates from inhalation of radon and its decay products were estimated with a mean of 0.19 mSv/y. There was some variation found between Summer and Winter measuerments, however, radon concentrations measured in Ground floors were significantly higher than those measured in the first and second floors. The results were found to be within the reference levels recommended by WHO of 100 Bq.m -3.

The main aim of this paper is to define and study the q(w)-deformed hyperbolic secant distribution. Here, we apply the deformation technique by introducing a parametric function q(w) under some certain appropriate assumptions. Some important corresponding properties are discussed. Moreover, some corresponding available measures and functions of this distribution are derived. Finally, a particular case is presented and elucidated