Research of stresses in the frame of the car crane

2021 ◽  
Vol 13 (1) ◽  
pp. 45-53
Author(s):  
Roman Zinko ◽  
◽  
Orest Gorbay ◽  
Andriy Polyakov ◽  
Vitaliy Popovych ◽  
...  
Keyword(s):  
Maximum Load ◽  
External Factors ◽  
Support Surface ◽  
Operating Cycle ◽  
Modes Of Operation ◽  
Technical Parameters ◽  
Load Mode ◽  
Margin Of Safety ◽  
Complete Deformation ◽  
The Impact

The problem of truck cranes is considered, in particular, the issues of ensuring the strength of the supporting structure of the chassis in different modes of operation, taking into account the peculiarities of the technological cycle. In truck cranes, the load loads are unevenly distributed. They depend not only on the weight of the crane and the load, but also on the position of the rotating part of the crane relative to the non-rotating, as well as on the departure of the boom. Loads on the support surface are transmitted through the outriggers. During the operation of the truck crane, the load on each remote support does not remain constant. Estimated loads, namely loads from the crane installation and cargo, will take into account different values of cargo weight, departure and crane height. Their size and location are determined according to the crane capacity diagram. Based on the analysis of scientific works on the impact of subsidence of outriggers in the ground during the operation of truck cranes, it can be argued that this factor is quite significant and must be taken into account when calculating the strength of the truck crane. Moreover, the load on each of the supports is different and changes with each operating cycle, when changing the trajectory and working with different loads. Based on the comparative analysis of existing analogues, the limits of variation of the main technical parameters for the design of a family of special chassis for truck cranes are determined. The dangerous modes of operation of the truck crane, the influence of both the main parameters and external factors on the magnitude and nature of the load were calculated. The results of the calculations are plots of complete deformation, equivalent stresses and margin of safety. In maximum load mode, the main load falls on the rear of the frame and the rear outriggers. Maximum and minimum altitude modes are not particularly dangerous. In addition, the greater the height, the less dangerous is the high flight of the arrow. Large capacity is possible only on small flights and heights.

Some reflections on social structure: Theoretical and practical aspects

2020 ◽  
Vol 18 (6) ◽  
pp. 1063-1078
Author(s):  
T.N. Skorobogatova ◽  
I.Yu. Marakhovskaya
Keyword(s):  
Service Industry ◽  
External Factors ◽  
Infrastructure Development ◽  
Social Infrastructure ◽  
Social Sphere ◽  
The Social ◽  
Study Results ◽  
The Republic ◽  
Internal And External Factors ◽  
The Impact

Subject. This article discusses the role of social infrastructure in the national economy and analyzes the relationship between the notions of Infrastructure, Service Industry and Non-Productive Sphere. Objectives. The article aims to outline a methodology for development of the social infrastructure of Russia's regions. Methods. For the study, we used the methods of statistical and comparative analyses. The Republic of Crimea and Rostov Oblast's social infrastructure development was considered as a case study. Results. The article finds that the level of social infrastructure is determined by a number of internal and external factors. By analyzing and assessing such factors, it is possible to develop promising areas for the social sphere advancement. Conclusions. Assessment and analysis of internal factors largely determined by the region's characteristics, as well as a comprehensive consideration of the impact of external factors will help ensure the competitiveness of the region's economy.

Dependency of Machine Efficiency on the Thermal Behavior of Induction Machines

Machines ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 9
Author(s):  
Svenja Kalt ◽  
Karl Ludwig Stolle ◽  
Philipp Neuhaus ◽  
Thomas Herrmann ◽  
Alexander Koch ◽  
...  
Keyword(s):  
Thermal Behavior ◽  
Electric Vehicles ◽  
Thermal Load ◽  
Load Capacity ◽  
Maximum Load ◽  
Induction Machines ◽  
Electric Machines ◽  
Model Parameters ◽  
Dynamic Operating ◽  
The Impact

The consideration of the thermal behavior of electric machines is becoming increasingly important in the machine design for electric vehicles due to the adaptation to more dynamic operating points compared to stationary applications. Whereas, the dependency of machine efficiency on thermal behavior is caused due to the impact of temperature on the resulting loss types. This leads to a shift of efficiency areas in the efficiency diagram of electric machines and has a significant impact on the maximum load capability and an impact on the cycle efficiency during operation, resulting in a reduction in the overall range of the electric vehicle. Therefore, this article aims at analyzing the thermal load limits of induction machines in regard to actual operation using measured driving data of battery electric vehicles. For this, a thermal model is implemented using MATLAB® and investigations to the sensitivity of model parameters as well as analysis of the continuous load capacity, thermal load and efficiency in driving cycles under changing boundary conditions are conducted.

scholarly journals Competitiveness Determinants of Moroccan Exports: Quantity-Based Analysis

2016 ◽  
Vol 8 (7) ◽  
pp. 140 ◽  
Author(s):  
Bilal Lotfi ◽  
Mohamed Karim
Keyword(s):  
European Union ◽  
Literature Review ◽  
Econometric Analysis ◽  
External Factors ◽  
The European Union ◽  
Export Competitiveness ◽  
Main Determinants ◽  
Internal And External Factors ◽  
The Impact ◽  
Relative Concept

<p>The term competitiveness is a relative concept whose perception changes with the level of conducted analysis (nation, sector, company). Thus, a variety of internal and external factors can have deep effects on the competitiveness of a given entity. This paper aims to evaluate the competitiveness of Moroccan exports by identifying the main determinants that explain their performance. This is particularly dealing with the impact of customs’ tariff, the tariff of import, foreign demand, the share of the non-residents in the capital of domestic enterprises and the investment rate compared to the value of exporters.</p><p>Moreover, this paper presents a literature review on competitiveness and examines the main results of our econometric analysis regarding the determinants of export competitiveness applied to the top ten branches most exporters in Morocco. The gained results allow confirming the sensitivity of exports by branch to the situation of Morocco’s main trading partner namely the European Union while emphasizing, quantitatively, on the role played by the investment effort undertaken by Moroccan exporting companies in improving the competitiveness of national exports.</p>

Interactions between pupae of the pine processionary moth (Thaumetopoea pityocampa) and parasitoids in a Pinus forest

2015 ◽  
Vol 105 (5) ◽  
pp. 621-628 ◽  
Author(s):  
C.P. Bonsignore ◽  
F. Manti ◽  
E. Castiglione
Keyword(s):  
Environmental Effects ◽  
Morphological Traits ◽  
External Factors ◽  
Thaumetopoea Pityocampa ◽  
Parasitoid Species ◽  
Pine Processionary Moth ◽  
Processionary Moth ◽  
The Impact ◽  
Positive Effect ◽  
Forest Lepidoptera

AbstractParasitoids are significant enemies of many economically important insects and there is some evidence to suggest that their actions have a role in terminating the outbreaks of forest Lepidoptera populations. In this study, we examined the impact of parasitoids on the pupae of the pine processionary moth, and highlighted the presence of several parasitoid species for this developmental stage. A higher rate of parasitism was found when the pupal density in the soil was reduced, but the rate of parasitism was not influenced by pupal morphological traits or by the presence or absence of a cocoon around a pupa. Of the external factors examined, a delay in the time of descent of larvae from the trees had a positive effect on the level of parasitism. Observational data indicated that dipteran and hymenopteran were the most abundant parasitoids to emerge from moth pupae. Our study highlights the complexity of the parasitoid–host dynamics, and stresses the importance of carefully determining environmental effects on host–parasitoid relations.

Accounting policy as a constituent of internal control and corporate economic security

2021 ◽  
Vol 17 (4) ◽  
pp. 664-681
Author(s):  
Yuliya N. STETSYUNICH ◽  
Andrei A. ZAITSEV
Keyword(s):  
Internal Control ◽  
Financial Management ◽  
Semantic Analysis ◽  
Economic Security ◽  
External Factors ◽  
Practical Significance ◽  
Negative Consequences ◽  
Internal And External Factors ◽  
The Impact ◽  
Accounting Policy

Subject. The article discusses the consistency of accounting policies, internal control and constituents of corporate economic security. Objectives. The study determines the process of articulating the term Accounting Policy at the legislative and normative levels nationwide and worldwide. We compare our own interpretations of corporate economic security. The article traces the impact of the accounting policy on areas of internal control and corporate economic securities. Methods. The study is based on general methods of research, such as the dialectical method, methods of analysis and synthesis, induction and deduction, and semantic analysis. Results. The article shows the impact of internal and external factors, which also influence corporate economic security and translate into the formation of corporate accounting policies. Conclusions and Relevance. Economic security is an aspect that every entity pursues. Therefore, it is important to thoroughly study how clauses of accounting policies influence the aspect from perspectives of business entities. The impact of constituents of corporate accounting policies, as evaluated herein, allow to consider adverse factors and help prevent negative consequences that internal and external factors may cause to corporate economic security. The findings contribute to accounting techniques for financial management in order to ensure the economic security. They are of practical significance for business leaders and financial personnel.

A General Ply Design for Aero Engine Composite Fan Blade

2017 ◽  
Author(s):  
Jiaguangyi Xiao ◽  
Yong Chen ◽  
Qichen Zhu ◽  
Jun Lee ◽  
Tingting Ma
Keyword(s):  
Composite Laminates ◽  
Composite Structures ◽  
Stacking Sequence ◽  
Composite Blade ◽  
Arduous Task ◽  
Aero Engine ◽  
Margin Of Safety ◽  
Fan Blade ◽  
The Impact ◽  
Ply Orientation

Composite fan blade ply lay-up design, which includes ply drop-off/shuffle design and stacking sequence design, makes fan blade structures different from traditional composite structures. It gives designers more freedom to construct high-quality fan blades. However, contemporary fan blade profiles are quite complex and twisted, and fan blade structures are quite different from regular composite structures such as composite laminates and composite wings. The ply drop-off design of a fan blade, especially for a fully 3D fan blade, is still an arduous task. To meet this challenge, this paper develops a ply lay-up way with the help of a software called Fibersim. The fully 3D fan blade is cut into ply pieces in Fibersim. As a result, an initial ply sequence is created and ply shuffle could revise it. Because of the complexity of ply shuffling, the ply shuffle table developed in this paper mainly refers to the design experience gained from simple plate-like laminate structures and some criterion. Besides, the impact of different ply orientation patterns on the reliability of composite fan blade is studied through static and modal numerical analysis. The results show that this ply lay-up idea is feasible for aero engine composite fan blade. Under the calculated rotating speeds, the ply stacking sequence 4 (i.e.[−45°/0°/+45°/0°] with the outer seven groups are [−45°/0°/−45°/0°]) shows the greatest margin of safety compared with other stacking sequences. Modal analysis shows that plies with different angles could have relatively big different impacts on blades vibration characteristics. The composite fan blade ply design route this paper presents has gain its initial success and the results in this paper might be used as basic references for composite blade initial structural design.

scholarly journals Performance analysis of photovoltaic plants installed in dairy cattle farms

2015 ◽  
Vol 46 (2) ◽  
pp. 62
Author(s):  
Remo Alessio Malagnino
Keyword(s):  
Energy Efficiency ◽  
Performance Analysis ◽  
Dairy Cattle ◽  
Geographical Information ◽  
Research Centre ◽  
Energy Yield ◽  
Pv System ◽  
Technical Parameters ◽  
Global Efficiency ◽  
The Impact

Electric production from renewable resources, such as solar photovoltaic (PV), is playing an increasingly essential role in the agricultural industry because of the progressive increase in the energy price from fossil fuels and the simultaneous decrease in the income deriving from farming activities. A central issue in the sustainable diffusion of PV technologies is represented by the actual energy efficiency of a PV system. For these reasons, a performance analysis has been carried out in order to assess the potentials offered by different PV plants within a defined geographical context with the aim of investigating the impact of each component has on the PV generator global efficiency and defining the main technical parameters that allow to maximise the annual specific electric energy yield of an architectonically integrated plant, installed in a dairy house, compared to a ground-mounted plant. The annual performances of three grid connected PV plants installed in the same dairy cattle farm have been analysed: two are architectonically integrated plants - <em>i.e.</em>, a rooftop unidirectional and a multi-field systems (both 99 kW<sub>p</sub>) - and the other is a ground-mounted plant (480 kW<sub>p</sub>). Furthermore, the electrical performances, estimated by the photovoltaic geographical information system (PVGIS), developed by the EU Joint Research Centre, and by an analytical estimation procedure (AEP), developed on the basis of a meteo-climatic database related to the records of the nearest weather station and integrated by the components’ technical specifications, have been compared with the actual yields. The best annual performance has been given by the ground-mounted PV system, with an actual increase of 26% and in the range of 6÷12% according to different estimations, compared to the integrated systems, which were globally less efficient (average total loss of 26÷27% compared to 24% of the ground-mounted system). The AEP and PVGIS software estimates showed a good level of reliability for mean deviations between the annual actual and estimated electrical power yields have been equal to 11.5% for each PV system given the actual irradiation’ s uncertainty during the examined year. The main technical parameters, crucial to maximise the energy yield from a ground-mounted PV system to an integrated one, have been identified in the Tilt and Azimuth angles. Indeed, once a variance of 3÷4% in the global efficiency has been confirmed when the type of PV system is changed, in the case of the unidirectional integrated PV plant, the high roof pitch and the almost South orientation guarantee a solar energy increase up to 18% higher than that obtainable on the horizontal plane and similar to the increase estimated for the ground-mounted generator (+20%). Hence, integrated PV systems, besides reaching the same levels of energy efficiency as those ground-mounted, are also more <em>sustainable</em> than the latter. This is true providing that there are both a suitable orientation and an accurate design, especially to prevent the PV panels’ warming during summer, on an already available surface that is, however, functional to the roof’s architecture.

Features of Semiconductors during Nanoindentation

2003 ◽  
Vol 779 ◽  
Author(s):  
Asta Richter ◽  
Bodo Wolf ◽  
Roger Smith ◽  
Margita Günther
Keyword(s):  
Phase Transformation ◽  
Hysteresis Loops ◽  
Maximum Load ◽  
Depth Sensing ◽  
Ion Energy ◽  
Loop Area ◽  
Area Reduction ◽  
Boron Implantation ◽  
The Impact ◽  
Constant Maximum

AbstractSi and InSb were subject to depth sensing multi-cycling nanoindentation. The load-depthcurves exhibited hysteresis loops which are explained in terms of pressure induced phase transformations. In order to study the impact of crystal distortions on phase transformation, the specimens were subject to boron implantation (ion energy 180 keV) of different implantation doses (1014 to 1017 ions/cm2) and indented without annealing. In InSb, the hysteresis loops disappeared after implantation of 1016 ions/cm2, and for Si with its stronger bonds, a dose of 3*1016/cm2 is required for the same effect. Indentation cycling with constant maximum load results in a sudden disappearance of the hysteresis loop after a small gradual loop area reduction during the first initial cycles.

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