A New Algorithm of Determining the Winch Braking Torque in Safe Working Condition

2013 ◽  
Vol 13 (21) ◽  
pp. 4405-4410
Author(s):  
Zhang YaoCheng ◽  
Luo Ying ◽  
Yang ZhaoJian ◽  
Zhang XiangYu
Aviation ◽  
2020 ◽  
Vol 23 (3) ◽  
pp. 97-103
Author(s):  
Ari Widyanti ◽  
Maisarah Firdaus

Flight attendants play a crucial role in the service of the airline industry. The aim of this present study is to examine the mental workload of flight attendants, and it possible relation to the flight duration. Two hundred and one Indonesian flight attendants participate voluntarily in this study by filling out a mental workload questionnaire, the NASA-TLX questionnaire, in the end of their flight schedule. Results show that the mental workload of flight attendants regardless the flight duration is on a range of medium mental workload. Based on flight duration, the optimal mental workload is for 1–2 hours of flight. Implications of the result are discussed.


2014 ◽  
Vol 8 (1) ◽  
pp. 107-112
Author(s):  
Wenhui Yue ◽  
Jianxin Weng ◽  
Liangpei Huang ◽  
Yongxing Zhu ◽  
Penghui Duan

Loads subjected by the boom system on the concrete pump are so complex, that fatigue cracks or fatigue fractures appear, which may lead to loss of property and casualty. However, when the concrete pump is functioning in safe condition, the damage of the boom system is reduced, thereby preventing the accidents. In order to select safe working conditions, a boom system of 37m concrete pump as research object should be adopted. The finite element analysis is carried out on the boom system based on MSC. Patran and Nastran, with regularly varying degrees, and changing trends of the maximum stresses subjected by booms with the change of degrees of booms, attained a safe condition of the boom system. Finally, taking the four kinds of typical foundation casting working conditions as example, the feasibility of using this condition to determine the safe working condition has been verified.


2019 ◽  
Vol 5 (1) ◽  
pp. 35-45
Author(s):  
Markus Dwiyanto Tobi ◽  
Alimuddin Mappa

The role of the power supply device is to produce, process and distribute energy sources. Telecommunication equipment can only operate if it has continuous supply. Therefore, to maintain the continuity of the supply, a UPS (Uninterruptable Power Supply) device system is needed so that the supply to the Essential Load device will remain available so that continuity will be maintained. This research designs and proposes how a series of automatic redundant switch systems on UPS to ensure the availability of power supply for the main equipment of telecommunications systems. The Auto switch circuit is designed to have 3 (three) working stages which will trigger the relay driver as control circuit, namely the normal working condition of the contactor input K1 is present, the input condition is zero (lost), and the input condition is present. This system can automatically supply power to telecommunications equipment.


On the basis of engineering and design surveys of the building, engineering-geological and geophysical studies of the soils of the territory conducted by the article authors, as well as with due regard for the results of studies conducted on this territory by other authors, the features of the foundations, soils of their foundation and engineering-geological conditions of the territory of the Melnikov House are established. It is shown that the Melnikov house is located under complex engineering-geological conditions on the territory of high geological risk, in the zone of influence of tectonic disturbance. To the North of the area there is a zone of intersection of the observed disturbance with a larger disturbance that can have an impact on geological processes. To the North-East of the site of the Melnikov House, a sharp immersion of the roof of carbon deposits was revealed. It promotes groundwater seepage into limestone of the carbonate strata from overlying water-bearing sands and activation of processes of suffusion removal and sinkhole phenomena of the soil. The surveyed area is assessed as potentially karst-hazardous and adjacent to it from the North-East territory as karst-dangerous. In this regard any construction on the adjacent territory can provoke activation of sinkhole phenomena on the surface. The foundations of the building are basically in working condition. Existing defects can be eliminated during repair. The foundation soils mainly have sufficient bearing capacity. Areas of the base with bulk soil can be reinforced. However, when developing a project for the reconstruction of the building and its territory, it should be taken into account that the design of the Melnikov House does not provide for its operation on the loads at the formation of sinkholes.


2006 ◽  
Vol 34 (1) ◽  
pp. 38-63 ◽  
Author(s):  
C. Lee

Abstract A tire slips circumferentially on the rim when subjected to a driving or braking torque greater than the maximum tire-rim frictional torque. The balance of the tire-rim assembly achieved with weight attachment at certain circumferential locations in tire mounting is then lost, and vibration or adverse effects on handling may result when the tire is rolled. Bead fitment refers to the fit between a tire and its rim, and in particular, to whether a gap exists between the two. Rim slip resistance, or the maximum tire-rim frictional torque, is the integral of the product of contact pressure, friction coefficient, and the distance to the wheel center over the entire tire-rim interface. Analytical solutions and finite element analyses were used to study the dependence of the contact pressure distribution on tire design and operating attributes such as mold ring profile, bead bundle construction and diameter, and inflation pressure, etc. The tire-rim contact pressure distribution consists of two parts. The pressure on the ledge and the flange, respectively, comes primarily from tire-rim interference and inflation. Relative contributions of the two to the total rim slip resistance vary with tire types, depending on the magnitudes of ledge interference and inflation pressure. Based on the analyses, general guidelines are established for bead design modification to improve rim slip resistance and mountability, and to reduce the sensitivity to manufacturing variability. An iterative design and analysis procedure is also developed to improve bead fitment.


Author(s):  
Vadim M. Vasilkevich ◽  
Ruslan V. Bogdanov ◽  
Elena V. Drozdova

Introduction. The working conditions of pharmaceutical industry workers are characterized by the combined effect of unfavorable factors of the production environment, among which the leading one is chemical. The aim of study is to substantiate the basic principles and criteria for hygienic regulation of pharmaceutical products in their production to ensure safe working conditions for employees based on the results of their own research and existing requirements of technical regulations. Materials and methods. Analysis of working conditions and the prevalence of health disorders in pharmaceutical workers (according to literature data), toxicological studies of pharmaceutical substances on laboratory animals, scientific justification of hygiene standards in the air of the working area. Results. Among employees of the pharmaceutical industry, the predominant forms of production-related health disorders are diseases of the respiratory system, as well as skin dermatitis of allergic origin, liver and biliary tract diseases. Based on the results of experimental studies of domestic pharmaceutical products for the treatment of cardiovascular, oncological and mental diseases that have priority socio-economic significance, the basic principles and features of the practice of justifying the hygienic standards of medicines in the air of the working area are developed and systematized. Conclusions. During hygienic rationing of medicines, it is necessary to use a differentiated approach that allows, based on the analysis of information about the chemical structure, physical and chemical characteristics, production conditions, pharmacotherapeutic activity, and the results of studying the toxic effect in an experiment on laboratory animals, to determine the maximum permissible content in the air of the working area of medicines or to justify the prohibition of isolation with reasoned recommendations for their safe production.


Author(s):  
L. Mavrina ◽  
E. Shaikhlislamova ◽  
I. Khasanova ◽  
L. Karimova ◽  
N. Muldasheva ◽  
...  

The relevance of the problem. Ensuring safe working conditions is currently an urgent problem of our time. Purpose of work. Analysis of bibliographic data on issues of occupational risk, industrial injuries among workers of the processing complex. Materials and methods. To achieve this goal, materials related to this topic were studied in the works of domestic and foreign scientists. Results. A lot of scientific works are devoted to the problem of assessing professional risk in the production of a processing complex. Modern research has proved that risk assessment is one of the main methods for analyzing the impact of various production factors on an employee. Conclusion Occupational morbidity and industrial injuries are a consequence of unsatisfactory conditions and labor protection in enterprises.


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