Effect of ionizing radiation on the stability and performance of the TAXUS Express2 paclitaxel-eluting stent

2004 ◽  
Vol 5 (3) ◽  
pp. 136-141 ◽  
Author(s):  
Christian Dilcher ◽  
Rosanna Chan ◽  
David Hellinga ◽  
Rufus Seabron ◽  
Rajbabu Pakala ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
And Performance ◽  
The Stability

Hygienic assessment of learning environment conditions (by the example of higher educational institutions of the city of Ufa)

2020 ◽  
Vol 99 (4) ◽  
pp. 405-411
Author(s):  
Elena Ju. Gorbatkova
Keyword(s):  
Ionizing Radiation ◽  
Educational Institutions ◽  
Higher Educational Institutions ◽  
Factors Affecting ◽  
Republic Of Bashkortostan ◽  
Average Relative Humidity ◽  
Higher Educational ◽  
The Republic ◽  
And Performance ◽  
The City

Introduction. The important factors affecting health and performance of young people are the conditions of education, in particular, a comfortable microclimate in the classrooms of higher educational institutions. Materials and methods. In view of the urgency of this problem, an analysis was made of the microclimate parameters of educational organizations of different profiles (Ufa city, the Republic of Bashkortostan). 294 classrooms were studied in 22 buildings of 4 leading universities in Ufa. A total of 3,822 measurements were taken to determine the parameters of the microclimate. The analysis of ionizing radiation in the aerial environment of classrooms. There was performed determination of radon and its affiliated products content. In order to assess the conditions and lifestyle of students of 4 higher educational institutions of the city of Ufa, we conducted an anonymous survey of 1,820 students of I and IV years of education. Results. The average temperature in the classrooms of all universities studied was 23.9±0.09 C. The average relative humidity in all classrooms was 34.2 ± 0.42%. Analysis of ionizing radiation (radon and its daughter products decay) in the aerial environment of the classrooms and sports halls located in the basement determined that the average annual equivalent equilibrium volumetric activity of the radon daughter products (EROA ± Δ222Rn) ranged from 28 ± 14 to 69 ± 34.5 meter, which meets the requirements established by SanPiN. Conclusion. The hygienic assessment of the microclimate parameters of educational institutions of various profile revealed a number of deviations from the regulated norms. The results indicate the need to control the parameters of the microclimate, both from the administration of universities, and from the professors. According to the results of the study, recommendations were prepared for the management of higher educational institutions in Ufa.

scholarly journals Analytical Modeling and Design of Novel Conical Halbach Permanent Magnet Couplings for Underwater Propulsion

2021 ◽  
Vol 9 (3) ◽  
pp. 290
Author(s):  
Yukai Li ◽  
Yuli Hu ◽  
Youguang Guo ◽  
Baowei Song ◽  
Zhaoyong Mao
Keyword(s):  
Permanent Magnet ◽  
Analytical Calculation ◽  
Underwater Propulsion ◽  
Conical Structure ◽  
Torque Analysis ◽  
Dynamic Seal ◽  
And Performance ◽  
The Stability ◽  
Propulsion Unit ◽  
Force Calculation

Permanent magnet couplings can convert a dynamic seal into a static seal, thereby greatly improving the stability of the underwater propulsion unit. In order to make full use of the tail space and improve the transmitted torque capability, a conical Halbach permanent magnet coupling (C-HPMC) is proposed in this paper. The C-HPMC combines multiple cylindrical HPMCs with different sizes into an approximately conical structure. Compared with the conical permanent magnet couplings in our previous work, the novel C-HPMC has better torque performance and is easy to process. The analytical calculation method of transmitted torque of C-HPMC is proposed on the basis of torque calculation of the three common types of HPMCs. The accuracy of the torque calculation of the three HPMCs is verified, and the torque performance of the three HPMCSs of different sizes is compared and discussed. The “optimal type selection” method is proposed and applied in the design of C-HPMC. Finally, on the basis of torque analysis calculation and axial force calculation, a complete flowchart of the design and performance analysis of C-HPMC is described.

Adaptive attitude-tracking control of spacecraft considering on-orbit refuelling

2020 ◽  
pp. 014233122097313
Author(s):  
Yiqi Xu
Keyword(s):  
Tracking Control ◽  
Closed Loop ◽  
Closed Loop System ◽  
Tracking Errors ◽  
Attitude Tracking ◽  
Control Scheme ◽  
Inertia Model ◽  
And Performance ◽  
Attitude Tracking Control ◽  
The Stability

This paper studies the attitude-tracking control problem of spacecraft considering on-orbit refuelling. A time-varying inertia model is developed for spacecraft on-orbit refuelling, which actually includes two processes: fuel in the transfer pipe and fuel in the tank. Based upon the inertia model, an adaptive attitude-tracking controller is derived to guarantee the stability of the resulted closed-loop system, as well as asymptotic convergence of the attitude-tracking errors, despite performing refuelling operations. Finally, numerical simulations illustrate the effectiveness and performance of the proposed control scheme.

Nondestructive Test on Typical Roadway Supports of a Mine via Drilling Core and Ground Penetrating Radar

2011 ◽  
Vol 368-373 ◽  
pp. 2411-2416
Author(s):  
Jian Ping Han ◽  
Hai Peng Liu
Keyword(s):  
Ground Penetrating Radar ◽  
Geological Structure ◽  
Surrounding Rock ◽  
Potential Threat ◽  
Real Performance ◽  
Design Requirements ◽  
And Performance ◽  
The Stability ◽  
Ground Penetrating ◽  
Drilling Core

Temporary or permanent supports are necessary in underground construction for maintaining the stability and limiting the damage of surrounding rock. Due to the uncertainty of geological structure, the specificity of the underground environment as well as other factors, the quality and performance of supporting structure are often difficult to satisfy the design requirements, which not only seriously affects the normal construction and operation of mines but also has the potential threat to the safety of underground production. In order to investigate the influence of the unfavorable geologic environment on supporting concrete and evaluate the real performance of roadway supports of a mine, 17 typical projects were chosen and the strength of supporting concrete was detected by nondestructive drilling core method. The result shows that the strength is widely less than the design value. Furthermore, 4 projects of them were investigated by the ground penetrating radar (GPR) in order to evaluate the feasibility of GPR in the performance investigation of the roadway supports of a mine. The results indicate that ground penetrating radar is capable of measuring the thickness of the support, the distribution of rebars and the defects of the surrounding rock.

Map Width Enhancement Technique for a Turbocharger Compressor

2013 ◽  
Vol 136 (6) ◽  
Author(s):  
Subenuka Sivagnanasundaram ◽  
Stephen Spence ◽  
Juliana Early
Keyword(s):  
Performance Improvement ◽  
Peak Pressure ◽  
Pressure Ratio ◽  
Comparison Study ◽  
Heavy Duty ◽  
Recirculating Flow ◽  
Heavy Duty Diesel ◽  
And Performance ◽  
The Stability ◽  
The Impact

This paper presents an investigation of map width enhancement and the performance improvement of a turbocharger compressor using a series of static vanes in the annular cavity of a classical bleed slot system. The investigation has been carried out using both experimental and numerical analysis. The compressor stage used for this study is from a turbocharger unit used in heavy duty diesel engines of approximately 300 kW. Two types of vanes were designed and added to the annular cavity of the baseline classical bleed slot system. The purpose of the annular cavity vane technique is to remove some of the swirl that can be carried through the bleed slot system, which would influence the pressure ratio. In addition to this, the series of cavity vanes provides a better guidance to the slot recirculating flow before it mixes with the impeller main inlet flow. Better guidance of the flow improves the mixing at the inducer inlet in the circumferential direction. As a consequence, the stability of the compressor is improved at lower flow rates and a wider map can be achieved. The impact of two cavity vane designs on the map width and performance of the compressor was highlighted through a detailed analysis of the impeller flow field. The numerical and experimental study revealed that an effective vane design can improve the map width and pressure ratio characteristic without an efficiency penalty compared to the classical bleed slot system without vanes. The comparison study between the cavity vane and noncavity vane configurations presented in this paper showed that the map width was improved by 14.3% due to a significant reduction in surge flow and the peak pressure ratio was improved by 2.25% with the addition of a series of cavity vanes in the annular cavity of the bleed slot system.

scholarly journals BRAIN AND EYE AS POTENTIAL TARGETS FOR IONIZING RADIATION IMPACT. Part І. THE CONSEQUENCES OF IRRADIATION OF THE PARTICIPANTS OF THE LIQUIDATION OF THE CHORNOBYL ACCIDENT

2020 ◽  
Vol 25 ◽  
pp. 90-129
Author(s):  
K. Loganovsky ◽  
◽  
P. Fedirko ◽  
K. Kuts ◽  
D. Marazziti ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Neurodegenerative Diseases ◽  
Nuclear Power ◽  
Radiation Effects ◽  
Radiation Risk ◽  
International Studies ◽  
Neurocognitive Deficit ◽  
Radiation Induced ◽  
And Performance ◽  
Medical Radiology

Background.Exposure to ionizing radiation could affect the brain and eyes leading to cognitive and vision impairment, behavior disorders and performance decrement during professional irradiation at medical radiology, including interventional radiological procedures, long-term space flights, and radiation accidents. Objective. The objective was to analyze the current experimental, epidemiological, and clinical data on the radiation cerebro-ophthalmic effects. Materials and methods. In our analytical review peer-reviewed publications via the bibliographic and scientometric bases PubMed / MEDLINE, Scopus, Web of Science, and selected papers from the library catalog of NRCRM – the leading institution in the field of studying the medical effects of ionizing radiation – were used. Results. The probable radiation-induced cerebro-ophthalmic effects in human adults comprise radiation cataracts, radiation glaucoma, radiation-induced optic neuropathy, retinopathies, angiopathies as well as specific neurocognitive deficit in the various neuropsychiatric pathology including cerebrovascular pathology and neurodegenerative diseases. Specific attention is paid to the likely stochastic nature of many of those effects. Those prenatally and in childhood exposed are a particular target group with a higher risk for possible radiation effects and neurodegenerative diseases. Conclusions. The experimental, clinical, epidemiological, anatomical and pathophysiological rationale for visual system and central nervous system (CNS) radiosensitivity is given. The necessity for further international studies with adequate dosimetric support and the follow-up medical and biophysical monitoring of high radiation risk cohorts is justified. The first part of the study currently being published presents the results of the study of the effects of irradiation in the participants of emergency works at the Chornobyl Nuclear Power Plant (ChNPP). Key words: ionizing radiation, cerebroophthalmic effects, neurocognitive deficit, radiation accident, radiation cataracts, macular degeneration.

scholarly journals STABILITY AND INSTABILITY OF AN OUTDOOR ILLUMINATION INSTALLATION

2004 ◽  
Vol 12 (4) ◽  
pp. 115-119
Author(s):  
Klaus-Dieter Fröhner ◽  
Ze Li
Keyword(s):  
Human Performance ◽  
Night Shift ◽  
Lighting Design ◽  
Work Efficiency ◽  
Safety And Health ◽  
Stability And Instability ◽  
Visual Tasks ◽  
And Performance ◽  
The Stability

Stability and instability are very important for the layout of real world processes concerning safety and health esp. when planned by scientists. The long‐term investigation of stability was carried out for the last ten years on the basis of the installation and the evaluation of an ergonomically designed outdoor illumination. In the depicted dynamic situation the lighting design influences directly visual discomfort and human performance and in the end stability and instability. The improvement of the adaptation of luminance and its influence on the visual tasks after the rearrangement are presented and discussed. The effective factors on the visual capability and performance of workers, work efficiency and potential accidents in the night shift, and furthermore the accelerators and barriers for the stability of the project are analysed and discussed.

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