Fatigue monitoring of climbing ropes

2020 ◽  
Vol 234 (4) ◽  
pp. 328-336
Author(s):  
Renato Galluzzi ◽  
Stefano Feraco ◽  
Enrico C Zenerino ◽  
Andrea Tonoli ◽  
Angelo Bonfitto ◽  
...  
Keyword(s):  
Visual Inspection ◽  
Impact Force ◽  
Damage Model ◽  
Rock Climbing ◽  
Fatigue Characteristic ◽  
Fatigue Monitoring ◽  
High Degree ◽  
The Impact ◽  
Force Data ◽  
Correct Estimate

Safety improvements in mountaineering gear have enabled the increasing popularity of rock climbing as a sport. Both amateurs and experts want to know the condition of their equipment with a high degree of reliability. For climbing ropes, diagnostics are only carried out qualitatively by visual inspection. The assessment is left to the personal judgment of the user, thus leaving considerable margins of uncertainty on the rope’s condition. To address this shortcoming, this article explores the possibility of estimating fatigue damage from the impact force on the rope. This value is estimated from the measurements of the climber’s acceleration using a wearable device. Then, force data are correlated to the fatigue characteristic of the rope. In this study, three ropes were used by professional climbers through different routes. After this field conditioning, the ropes were tested following the UIAA standard and compared to a control rope. The results show that the proposed method can estimate the rope cumulative damage, but it relies on the accuracy of the damage model. In particular, the parameter describing the contact between the rope and the runner is important for a correct estimate.

scholarly journals Experimental Studies on a Powder-Snow Avalanche

1989 ◽  
Vol 13 ◽  
pp. 129-134 ◽  
Author(s):  
K. Kawada ◽  
K. Nishimura ◽  
N. Maeno
Keyword(s):  
Large Scale ◽  
Impact Force ◽  
Experimental Studies ◽  
Block Type ◽  
Impact Forces ◽  
Wave Forms ◽  
The Impact ◽  
Force Data

To make clear the structure and behaviour of a large-scale avalanche, the impact force-data obtained in the avalanche project of 1972–78 were analysed in detail. The wave forms of impact forces are classified into two types. Type 1 is composed of many separate spikes each of which represents the collision of a snow block. Type 2 has wider peaks, caused by collisons of snow blocks mixed with fluidized snow. Most of the type 1 peaks were in the width range corresponding to 0.005–0.01 s duration, and most type 2 peaks fell into the 0.02–0.1 s range.The internal velocities of an avalanche were estimated by calculating cross-correlation spectra for a time series of impact-force records. It was discovered that these internal velocities varied from 10 to 50 m/s over time. The mean distance between snow blocks was found to be in the range 1.6–5.4 m in a type 1 avalanche, and between 0.7 and 3 m in type 2 avalanches. Sizes of snow blocks or snow clouds of type 1 and type 2 were in ranges 0.26–0.52 and 0.37–1.9 m, respectively.This paper also reports on the project created to initiate artificial powder-snow avalanches in the Shiai-dani area and to make systematic observations of a variety of physical aspects. Results obtained in 1988 for both artificial and natural avalanches are given.

scholarly journals Experimental Studies on a Powder-Snow Avalanche

1989 ◽  
Vol 13 ◽  
pp. 129-134 ◽  
Author(s):  
K. Kawada ◽  
K. Nishimura ◽  
N. Maeno
Keyword(s):  
Large Scale ◽  
Impact Force ◽  
Experimental Studies ◽  
Block Type ◽  
Impact Forces ◽  
Wave Forms ◽  
The Impact ◽  
Force Data

To make clear the structure and behaviour of a large-scale avalanche, the impact force-data obtained in the avalanche project of 1972–78 were analysed in detail. The wave forms of impact forces are classified into two types. Type 1 is composed of many separate spikes each of which represents the collision of a snow block. Type 2 has wider peaks, caused by collisons of snow blocks mixed with fluidized snow. Most of the type 1 peaks were in the width range corresponding to 0.005–0.01 s duration, and most type 2 peaks fell into the 0.02–0.1 s range. The internal velocities of an avalanche were estimated by calculating cross-correlation spectra for a time series of impact-force records. It was discovered that these internal velocities varied from 10 to 50 m/s over time. The mean distance between snow blocks was found to be in the range 1.6–5.4 m in a type 1 avalanche, and between 0.7 and 3 m in type 2 avalanches. Sizes of snow blocks or snow clouds of type 1 and type 2 were in ranges 0.26–0.52 and 0.37–1.9 m, respectively. This paper also reports on the project created to initiate artificial powder-snow avalanches in the Shiai-dani area and to make systematic observations of a variety of physical aspects. Results obtained in 1988 for both artificial and natural avalanches are given.

Experiment of the Rockfall Impact Characteristic onto Gravel Cushion

2012 ◽  
Vol 430-432 ◽  
pp. 1729-1732 ◽  
Author(s):  
Hong Mei Tang ◽  
Lin Feng Wang ◽  
Hong Kai Chen ◽  
Ren Jie Wu
Keyword(s):  
Moisture Content ◽  
Impact Force ◽  
Soil Mass ◽  
Rock Fall ◽  
Mountainous Area ◽  
Wavelet Theory ◽  
Geological Disasters ◽  
Prevention And Cure ◽  
The Impact ◽  
Force Data

Rockfall is one of common geological disasters in the mountainous area. The experiment gained the impact waves for cushion soil mass contained 12density, 4 soil-rock ratio, 4 cushion obliquity, 3 moisture content, 3 rockfall quality, 5 height of rock fall. Used the wavelet theory to deal with the experiment waves, analyzed the experiment results: with rock’s mass, the height and density increased, the impact force is increasing, or the impact force is decreasing with the moisture content and cushion inclination increasing. The impact force spreads from the point of rockfall to all directions. The impact force data of the experiment is a little large than others, so this method provides a gist for choosing the prevention and cure measure for rockfall.

Prospects for the use of the “model budget” in the distribution of equalization grants in Russia

2019 ◽  
pp. 21-38
Author(s):  
Alexander N. Deryugin ◽  
Ilya A. Sokolov
Keyword(s):  
Intergovernmental Relations ◽  
Unfunded Mandates ◽  
Interregional Inequality ◽  
Alternative Approach ◽  
The Russian Federation ◽  
Regional Authorities ◽  
High Degree ◽  
Equalization Grants ◽  
The Impact ◽  
Budget Expenditure

The paper analyzes the impact of the “model budget” on the problems of intergovernmental relations in the Russian Federation: a high proportion of expenditure obligations of regional and local budgets and a high degree of interregional inequality in fiscal capacity and socio-economic development. It was concluded that the planned broader use of the “model budget” will not solve the problem of unfunded mandates and will lead first to a significant reduction in incentives for regional authorities to develop the territorial revenue base, and then to economic slowdown in the country. As an alternative approach to improving intergovernmental relations, options are being considered for adjusting the parameters of the equalization transfers distribution formula, the procedure for determining their total volume and calculating the budget expenditure index. In solving the problem of unfunded mandates, an equally important role is given to the procedure for preparing a financial and economic rationale for draft laws.

Some thought on the Estimating of the Impact Force by an Experiment

2019 ◽  
Vol 7 (2) ◽  
pp. 205-213
Author(s):  
Yong-Doo Kim ◽  
Seung-Jae Lim ◽  
Hyun-Ung Bae ◽  
Kyoung-Ju Kim ◽  
Chin-Ok Lee ◽  
...  
Keyword(s):  
Impact Force ◽  
The Impact

Агрономическая эффективность промышленной (голландской) технологии возделывания картофеля

2018 ◽  
Author(s):  
C. Coy ◽  
A.V. Shuravilin ◽  
O.A. Zakharova
Keyword(s):  
Heavy Metals ◽  
Regression Analysis ◽  
Positive Response ◽  
Growth Yield ◽  
Correlation And Regression Analysis ◽  
Yield And Quality ◽  
Quality Of Products ◽  
High Degree ◽  
The Impact

Приведены результаты исследований по изучению влияния промышленной технологии возделывания картофеля на развитие, урожайность и качество продукции. Выявлена положительная реакция растений на подкормку K2SO4 в период посадки. Корреляционно-регрессионный анализ урожайности и качества клубней выявил высокую степень достоверности результатов опыта. Содержание нитратов и тяжелых металлов в клубнях было ниже допустимых величин.The results of studies on the impact of industrial technology of potato cultivation on growth, yield and quality of products. There was a positive response of plants to fertilizer K2SO4 in the period of planting. Correlation and regression analysis of yield and quality of tubers revealed a high degree of reliability of the results of experience. The contents of nitrates and heavy metals in tubers was below the permissible values.

Te inf uence of ergonomic factors on the formation of occupational risk of health disorders of agricultural machine operators

2019 ◽  
Vol 1 (7) ◽  
pp. 400-405
Author(s):  
Tamara A. Novikova ◽  
Aleksey N. Danilov ◽  
Vladimir F. Spirin
Keyword(s):  
Physical Activity ◽  
Functional Condition ◽  
Anthropometric Data ◽  
Agricultural Machine ◽  
Machine Operators ◽  
Health Disorders ◽  
Space Layout ◽  
Combine Harvesters ◽  
High Degree ◽  
The Impact

Introduction. T e leading place in the structure of occupational morbidity of agricultural machine operators is occupied by vertebroneurological diseases, the development of which can be associated with the impact of ergonomic factors of labor activity. T e aim of the study is to assess the ergonomic factors of working conditions on mobile agricultural machinery and to identify their impact on the formation of health disorders of agricultural machine operators. Materials and methods. Complex physiological and ergonomic researches at operation of tractors and combine harvesters of old samples of domestic production including an assessment of the organization of workplaces on compliance to requirements of ergonomics and anthropometric data of workers, temporary, statodynamic, biomechanical characteristics of working poses and movements, a functional condition of machine operators (130 people aged 20–45 years with professional experience of work not less than three years) in dynamics of a work shift are carried out. Anthropometric studies were conducted among male machine operators (663 people) aged 18–59 years and with experience in the profession for more than three years. Results. The discrepancy between the size and space-layout parameters of workplaces ergonomic requirements and anthropometric data of machine operators, causing the formation of uncomfortable working positions, increasing physical activity and the severity of the labor process. A high degree of correlation between changes in the parameters of the neuromuscular system and the severity of the discrepancy between the ergonomic parameters of anthropometric characteristics of machine operators (r=0,7). T e results of the research allowed to determine the priority measures for the prevention of vertebroneurological diseases in agricultural machine operators. Conclusions. T e organization of workplaces on domestic tractors and combine harvesters of old samples does not meet the ergonomic requirements and anthropometric data of machine operators, which is the reason for the formation of an uncomfortable working posture, increased statodynamic physical activity, early development of fatigue and fatigue in the process, which can cause the development of pathological conditions of the spine and ligamentous apparatus. Ergonomic improvement of workplaces is one of the priority measures to preserve the health of agricultural machine operators.

scholarly journals Advertising Media Impact in Consumer Buying Behavior

2019 ◽  
Vol 8 ◽  
pp. 54-56
Author(s):  
Ashmita Dahal Chhetri
Keyword(s):  
Consumer Behavior ◽  
Young Male ◽  
Electronic Media ◽  
Buying Behavior ◽  
Media Impact ◽  
High Degree ◽  
The Impact ◽  
Buying Behaviors ◽  
The Relationship ◽  
Better Than

Advertisements have been used for many years to influence the buying behaviors of the consumers. Advertisements are helpful in creating the awareness and perception among the customers of a product. This particular research was conducted on the 100 young male and female who use different brands of product to check the influence of advertisement on their buying behavior while creating the awareness and building the perceptions. Correlation, regression and other statistical tools were used to identify the relationship between these variables. The results revealed that the relationship between media and consumer behavior is positive. The adve1tising impact on sales and there is positive and high degree relationship between advertising and consumer behavior. The impact on advertising of a product of electronic media is better than non-electronic media.

Statistical micromechanical damage model for SH-SFRC under tensile load considering the interfacial slip-softening and matrix spalling effects

2021 ◽  
pp. 105678952110112
Author(s):  
Hehua Zhu ◽  
Xiangyang Wei ◽  
J Woody Ju ◽  
Qing Chen ◽  
Zhiguo Yan ◽  
...  
Keyword(s):  
Strain Hardening ◽  
Steel Fiber ◽  
Damage Model ◽  
Fiber Reinforced Concrete ◽  
Uniaxial Tensile ◽  
Interfacial Slip ◽  
Fiber Reinforced ◽  
Micromechanical Damage ◽  
The Impact ◽  
Micromechanical Damage Model

Strain hardening behavior can be observed in steel fiber reinforced concretes under tensile loads. In this paper, a statistical micromechanical damage framework is presented for the strain hardening steel fiber reinforced concrete (SH-SFRC) considering the interfacial slip-softening and matrix spalling effects. With a linear slip-softening interface law, an analytical model is developed for the single steel fiber pullout behavior. The crack bridging effects are reached by averaging the contribution of the fibers with different inclined angles. Afterwards, the traditional snubbing factor is modified by considering the fiber snubbing and the matrix spalling effects. By adopting the Weibull distribution, a statistical micromechanical damage model is established with the fracture mechanics based cracking criteria and the stress transfer distance. The comparison with the experimental results demonstrates that the proposed framework is capable of reproducing the SH-SFRC’s uniaxial tensile behavior well. Moreover, the impact of the interfacial slip-softening and matrix spalling effects are further discussed with the presented framework.

scholarly journals Measuring spatial price differentials at the basic heading level: a comparison of stochastic index number methods

2021 ◽  
Author(s):  
Sebastian Weinand
Keyword(s):  
Price Level ◽  
Consumer Price Index ◽  
Index Number ◽  
Price Data ◽  
Estimation Efficiency ◽  
Spatial Price ◽  
Price Comparisons ◽  
High Degree ◽  
The Impact

AbstractSpatial price comparisons rely to a high degree on the quality of the underlying price data that are collected within or across countries. Below the basic heading level, these price data often exhibit large gaps. Therefore, stochastic index number methods like the Country–Product–Dummy (CPD) method and the Gini–Eltetö–Köves–Szulc (GEKS) method are utilised for the aggregation of the price data into higher-level indices. Although the two index number methods produce differing price level estimates when prices are missing, the present paper demonstrates that both can be derived from exactly the same stochastic model. For a specific case of missing prices, it is shown that the formula underlying these price level estimates differs between the two methods only in weighting. The impact of missing prices on the efficiency of the price level estimates is analysed in two simulation studies. It can be shown that the CPD method slightly outperforms the GEKS method. Using micro data of Germany’s Consumer Price Index, it can be observed that more narrowly defined products improve estimation efficiency.

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