Design of electro-mechanical actuator for medium sized helicopter and a test platform for its testing and verification

This paper presents the design of an electro-mechanical actuator that is used for actuation of a medium sized helicopter. The designed actuator consists of a commercially available electro-mechanical cylinder EMC40 from Rexroth Bosch and a brushless DC motor EC45 from maxon motor. Cylinder and the motor are connected by a custom-made gearbox, which allows for their parallel axial mount. In addition to the actuator, the paper describes a test platform that can be used to emulate the forces generated by an actual helicopter. Designed test platform consists of a torsional spring and an AC motor with excentre. Frequency regulator is used to achieve the desired frequency of the force. Experimental results obtained by testing the designed actuator on the test platform are also given in the paper

Design of electro-mechanical actuator for medium sized helicopter and a test platform for its testing and verification

This paper presents the design of an electro-mechanical actuator that is used for actuation of a medium sized helicopter. The designed actuator consists of a commercially available electro-mechanical cylinder EMC40 from Rexroth Bosch and a brushless DC motor EC45 from maxon motor. Cylinder and the motor are connected by a custom-made gearbox, which allows for their parallel axial mount. In addition to the actuator, the paper describes a test platform that can be used to emulate the forces generated by an actual helicopter. Designed test platform consists of a torsional spring and an AC motor with excentre. Frequency regulator is used to achieve the desired frequency of the force. Experimental results obtained by testing the designed actuator on the test platform are also given in the paper

Patients’ trust in the health care system and physiotherapists

Introduction: The assessment of the health-care system by its beneficiaries is based on evaluation of the public perception in regards to the performance of healthcare workers, the functioning of the health system, the effectiveness of health policy measures, and a number of other components. The aim of this study was to determine patients’ trust in the work of physiotherapists and the health-care system; determine the quality of communication between the patient and the physiotherapist and determine the quality of cooperation between healthcare workers in the provision of health services.Methods: The study is descriptive, conducted in five cities: Banja Luka, Bihać, Herceg Novi, Nikšić, and Podujevo. The confidence in health-care questionnaire developed by Calnan and Sanford (2004) was used as a research instrument, containing six areas of research: Attitude toward the patient, Health policy and patient care, Professionalism and expertise, Quality of health care, Communication and information, and Quality of cooperation.Results: The mean age of the subjects was 41 years, 24 females and 26 males. Subjects expressed the greatest satisfaction on subscales I - Attitude toward the patient (27.44 ± 3.59 out of 30) and IV - Quality of health care (36.60 ± 4.19 out of 40), which represents 91.5% of the possible maximum. This is followed by subscale V - Communication and information (20.8 ± 3.17 out of 25) corresponding to 83.2% of the possible maximum, followed by subscale III - Professionalism and expertise (15.68 ± 3.29 out of 20) which represents 78.4% of the possible maximum. Subjects showed the least satisfaction on subscales II - Health policy and patient care (16.94 ± 5.56 out of 25), which represents 67.8% of the possible maximum, and subscales VI - Quality of cooperation (9.94 ± 0.42 out of 15) which corresponds to 66.3% of the possible maximum.Conclusions: The research showed a high degree of satisfaction of subjects in various fields, which indicates a high degree of confidence in the work of physiotherapists and the health-care system. Research on a larger sample in needed for creation and implementation of the guidelines in the strategic documents of the countries in the region and for improvement of health policies and patient care

Determination of specific antibodies titre to salmonella enteritidis by elisa technique in several selected flocks of laying hens

In this paper, the antibody titre to Salmonella enteritidis (SE) was examined by the ELISA method in two flocks of laying hens, where during routine bacteriological investigations Salmonellae was never isolated, and in one flock where Colysepticemia was diagnosed and Salmonella isolated accidentally. In the flocks were Salmonellae were not isolated, a titre with a high level of specific antibodies to SE was discovered (15 and 45%), while the flock with accidental findings of SE was poorly positive (5%). These results point to the necessity of introducing serological monitoring to SE so that the infection of salmonella may be discovered early and the prevalence in the flock determined, and also for the purpose of applying adequate measures that could reduce the possibility of secretion of SE through eggs

Computer-aided technologies in diagnostics and therapy of impacted teeth

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Numerical study of transient three-dimensional heat conduction problem with a moving heat source

A numerical study of transient three-dimensional heat conduction problem with a moving source is presented. For numerical solution Douglas-Gunn alternating direction implicit method is applied and for the moving heat source flux distribution Gaussian function is used. An influence on numerical solution of input parameters figuring in flux boundary conditions is examined. This include parameters appearing in Gaussian function and heat transfer coefficient from free convection boundaries. Sensitivity of cooling time from 800 to 500°C with respect to input parameters is also tested

Determination of the Actual Stress-Strain Diagram for Undermatching Welded Joint Using DIC and FEM

This paper presents new methodology for determining the actual stress-strain diagram based on analytical equations, in combination with numerical and experimental data. The first step was to use the 3D digital image correlation (DIC) to estimate true stress-strain diagram by replacing common analytical expression for contraction with measured values. Next step was to estimate the stress concentration by using a new methodology, based on recently introduced analytical expressions and numerical verification by the finite element method (FEM), to obtain actual stress-strain diagrams, as named in this paper. The essence of new methodology is to introduce stress concentration factor into the procedure of actual stress evaluation. New methodology is then applied to determine actual stress-strain diagrams for two undermatched welded joints with different rectangular cross-section and groove shapes, made of martensitic steels X10 CrMoVNb 9-1 and Armox 500T. Results indicated that new methodology is a general one, since it is not dependent on welded joint material and geometry

Determination of the Actual Stress-Strain Diagram for Undermatching Welded Joint Using DIC and FEM

This paper presents new methodology for determining the actual stress-strain diagram based on analytical equations, in combination with numerical and experimental data. The first step was to use the 3D digital image correlation (DIC) to estimate true stress-strain diagram by replacing common analytical expression for contraction with measured values. Next step was to estimate the stress concentration by using a new methodology, based on recently introduced analytical expressions and numerical verification by the finite element method (FEM), to obtain actual stress-strain diagrams, as named in this paper. The essence of new methodology is to introduce stress concentration factor into the procedure of actual stress evaluation. New methodology is then applied to determine actual stress-strain diagrams for two undermatched welded joints with different rectangular cross-section and groove shapes, made of martensitic steels X10 CrMoVNb 9-1 and Armox 500T. Results indicated that new methodology is a general one, since it is not dependent on welded joint material and geometry

The frequency of the use of information and communication technologies in school age children and musculoskeletal disorders connected with their use

Introduction: information and communication technology (ICT) has multiplied its availability and use, resulting in enormous usage, especially among school-age children, who use it for an average of 7.5 hours per day. The amount of time adolescents spend in front of electronic screens has increased significantly between the ages of 10 and 14, but there are significant gender changes. For boys, this increase is 41.6 minutes per day, while for girls it is 22.7 minutes per day. Methods: The study is designed as an epidemiological, cross-sectional, descriptive-analytic, comparative study. The study will be conducted in the form of an online questionnaire on the Microsoft Forums platform during the period 12/15/2021 to 12/30/2021. Respondents were able to access the request for consent using a link and a QR code, which was previously signed by a parent/guardian giving consent for children to participate in this study. Results: The results of this study show that school-aged children generally use cell phones with a touch screen between 2 and 3 hours daily during the work week (39.2%) and TV (39.5%). Pain caused by ICT use in the past 12 months occurred mainly in the neck/shoulder area (42.4%), while pain in the previous month occurred mainly in the lower extremities (29.1%). Conclusion: Increased use of ICT devices was associated with higher levels of musculoskeletal symptoms. The higher pain burden in various body parts is of concern, and further research on the effects of ICT device use in adolescents is needed and warranted

Work Caused Musculoskeletal Disorders in Health Professionals

Introduction: Work-related musculoskeletal disorders (WRMSDs) are the most common work-related diseases and describe a wide range of degenerative and inflammatory conditions affecting blood vessels, peripheral nerves, joints, ligaments, tendons, and muscles. WRMSDs are becoming an increasing problem in modern society. They are the second biggest cause of short-term or temporary incapacity for work just following a cold. At the workplace, health professionals represent a very vulnerable category in terms of musculoskeletal disorders (MSDs) development. It is estimated that almost one-third of all cases of absence from work among health care professionals are related to MSDs. Studies also show that a large number of health professionals report the occurrence of MSDs in one or more regions of the body, with a problem with the lower back being one of the most common.Methods: This article presents a non-experimental (qualitative) research, or a scientific review of the published literaturewhere the databases were reviewed in which the keywords for the review were: MSDs, work, health, intervention program,and ergonomics. Various databases were used in the preparation of this article, including PubMed, Google Scholar, Medline, Hrčak, Dabar, Science Direct, and Science Citation.Results: The results include a review and analysis of eighteen published scientific articles in the period 2001-2020. The studies published in these articles has been conducted in the United States, Australia, Switzerland, Portugal, Slovenia, Turkey, China, Nigeria, Israel, Tunisia, Iran, Croatia, Taiwan, Bangladesh, Serbia, Macedonia, and Greece.Conclusion: This article should indicate the magnitude of the problems of WRMSDs in health professionals and that this topic is an inexhaustible and very interesting basis for further studies by current and future researchers to create strategies for the prevention and treatment of this disorder and to eliminate its causes