Mathematical modeling on multi-stage series crushing ratio distribu- tion based on fuzzy physical programming

Double-layer, multi-roller plate crusher is a new device, that uses a multi-stage series crushing style to break particles, with the crushing ratio distribution directly influencing the machine＇s performance. Three crushing ratios of 2.25, 2.15 and 2.01, used for fuzzy physical programming, were determined. The comparison of the optimized result between the double-layer multi-roller plate crusher and a high pressure roll grinder showed that the double-layer multi-roller plate crusher had a better performance, reducing crushing force and wear.

Influence of Physical Activity on Concentration of Macro-and Microelements in Physically Active Students＇ Hair

The aim of the work is to evaluate the influence of physical activity character on concentration of macro-and microelements in hair of physically active students. 127 students of I-IV year of Physical Education program at Lithuanian University of Educational Sciences participated in the research, aged from 20 to 24. They were split into three groups. The first （I） group （n = 48） consisted of endurance sport athletes （skiers, biathlon athletes, middle and long distance runners, rowers and cyclists）. The second group （II） （n = 61） was made up of the basketball, football, handball and volleyball players. The third group （III） consisted of combat sports （wrestling and boxing） athletes （n = 18）. For establishing the concentration of macro- and microelements in hair, x-ray fluorescence method was applied, using CEP-1 ELVAX （MP.MN 3730-2011） device. The results showed that the hair of the students of Physical Education program, practicing endurance sports possessed more calcium, copper, manganese in comparison to the athletes practicing other sports. Concentration of the main elements--zinc, iron, selenium and chromium in the hair of combat sports representatives was statistically significant. Concentration of potassium was also the greatest in this group of the investigated. However, this group of athletes also possessed the greatest values of toxic elements （plumbum, arsenic） in their hair, comparing to the athletes of endurance sport and players. In their hair, hydrargyrum concentration was significantly greater comparing to the values of this element in players＇ hair. The greatest mean values of cadmium were established in players＇ hair.

Non-probabilistic Robust Optimal Design Method

For the purpose of dealing with uncertainty factors in engineering optimization problems, this paper presents a new non-probabilistic robust optimal design method based on maximum variation estimation. The method analyzes the effect of uncertain factors to objective and constraints functions, and then the maximal variations to a solution are calculated. In order to guarantee robust feasibility the maximal variations of constraints are added to original constraints as penalty term; the maximal variation of objective function is taken as a robust index to a solution; linear physical programming is used to adjust the values of quality characteristic and quality variation, and then a bi-level mathematical robust optimal model is constructed. The method does not require presumed probability distribution of uncertain factors or continuous and differentiable of objective and constraints functions. To demonstrate the proposed method, the design of the two-bar structure acted by concentrated load is presented. In the example the robustness of the normal stress, feasibility of the total volume and the buckling stress are studied. The robust optimal design results show that in the condition of maintaining feasibility robustness, the proposed approach can obtain a robust solution which the designer is satisfied with the value of objective function and its variation.

PILOT PROGRAM OF KNOWLEDGE INNOVATION AT INSTITUTE OF THEORETICAL PHYSICS

Ⅰ. REVIEW The Institute of Theoretical Physics (ITP) of the CAS was founded in 1978 with the personal approval of Comrade Deng Xiaoping, in the same year when the Third Plenary Session of the Central Committee of the CPC (Communist Party of China) was convened. Over the past 20 years, the Institute has been striving to explore a road for sound development in a bid to achieve the following targets: In regard to research, the institute strives

Frailty:Past,present,and future?

The prevalence of frailty across the world in older adults is increasing dramatically and having frailty places a person at increased risk for many adverse health outcomes,including impaired mobility,falls,hospitalizations,and mortality.Globally,the concept of frailty is gaining attention and the scientific field has made great strides in identifying and conceptually defining frailty through consensus conferences,in advancing the overall science of frailty by drawing on basic science discoveries including concepts surrounding the hallmarks of aging,resilience,and intrinsic capacities,and in identifying the many challenges faced by professionals within diverse clinical settings.Currently,it is thought that frailty is preventable,thus the identification of a person's degree of frailty is vital.Identification of frailty is achievable through widely used frailty screening tools,which are valid,reliable,and easy to use.Following the identification of a person's degree of frailty,targeted intervention strategies,such as physical activity programs must be implemented.In this perspective,we provide a historical perspective of the frailty field since the last quarter of the 20th century to present.We identify the proposed underlying patho-physiology of multiple physiological systems,including compromised homeostasis and resilience.Next,we outline the available screening tools for frailty with a physical performance assessment and highlight specific benefits of physical activity.Lastly,we discuss current scientific evidence supporting the physical activity rec-ommendations for the aging population and for older adults with frailty.The goal is to emphasize early detection of frailty and stress the value of physical activity.