scholarly journals NUMERICAL SIMULATION OF YIELDING SUPPORTS IN THE SHAPE OF ANNULAR TUBES UNDER STATIC AND SHORT-TERM DYNAMIC LOADING

2017 ◽  
Vol 13 (4) ◽  
pp. 103-113 ◽  
Author(s):  
Oleg G. Kumpyak ◽  
Nikita V. Mescheulov
Keyword(s):  
Dynamic Loading ◽  
Economic Losses ◽  
Building Structures ◽  
Short Term ◽  
Linear Character ◽  
Numerical Studies ◽  
Condensed Explosives ◽  
Fuel Mixtures ◽  
Prevention Methods ◽  
The Given

Occurrence of extreme man-made impacts on buildings and structures has become frequent lately as a consequence of condensed explosives or explosive combustion of gas- vapor or air-fuel mixtures. Such accidents involve large human and economic losses, and their prevention methods are not always effective and reasonable. The given research aims at studying the way of enhancing explosion safety of building structures by means of yielding supports. The paper presents results of numerical studies (finite element, 3D nonlinear) of strength and deformability of yielding supports in the shape of annular tubes under static and short-term dynamic loading. The degree of influence of yielding supports was assessed taking into account three peculiar stages of deformation: elastic; elasto-plastic; elasto-plastic with hardening. The methodology for numerical studies performance was described. It was established that rigidity of yielding supports influences significantly their stress-strain state. The research determined that with increase of deformable elements rigidity dependency between load and deformation of yielding supports in elastic and plastic stages have linear character. Significant reduction of dynamic response and increase of deformation time of yielding supports was observed by increasing the plastic component. Therefore it allows assuming on possibility of their application as supporting units in reinforced concrete constructions

scholarly journals Computer simulation of yielding supports under static and short-term dynamic load

2018 ◽  
Vol 143 ◽  
pp. 01014
Author(s):  
Oleg Kumpyak ◽  
Nikita Mescheulov
Keyword(s):  
Economic Losses ◽  
Building Structures ◽  
Short Term ◽  
Element Analysis ◽  
Linear Character ◽  
Numerical Studies ◽  
Strength And Deformation ◽  
Prevention Methods ◽  
The Given ◽  
Program Software

Dynamic impacts that became frequent lately cause large human and economic losses, and their prevention methods are not always effective and reasonable. The given research aims at studying the way of enhancing explosion safety of building structures by means of yielding supports. The paper presents results of numerical studies of strength and deformation property of yielding supports in the shape of annular tubes under static and short-term dynamic loading. The degree of influence of yielding supports was assessed taking into account three peculiar stages of deformation: elastic; elasto-plastic; and elasto-plastic with hardening. The methodology for numerical studies performance was described using finite element analysis with program software Ansys Mechanical v17.2. It was established that rigidity of yielding supports influences significantly their stress-strain state. The research determined that with the increase in deformable elements rigidity dependence between load and deformation of the support in elastic and plastic stages have linear character. Significant reduction of the dynamic response and increase in deformation time of yielding supports were observed due to increasing the plastic component. Therefore, it allows assuming on possibility of their application as supporting units in RC beams.

scholarly journals Numerical and experimental studies of deflections of conventional and strengthened reinforced concrete bendable elements under short-term dynamic loading

2021 ◽  
Vol 13 (S) ◽  
pp. 179-192
Author(s):  
Dmitry Yu. SARKISOV ◽  
Georgy I. ODNOKOPYLOV ◽  
Vladimir V. KRYLOV ◽  
Andriy O. ANNENKOV
Keyword(s):  
Shock Wave ◽  
Experimental Investigation ◽  
Reinforced Concrete ◽  
Dynamic Loading ◽  
Software Package ◽  
Building Structures ◽  
Ansys Software ◽  
Short Term ◽  
Actual Problem ◽  
Explicit Dynamics

The relevance of this study is conditioned by the technical complexity of the design solutions for construction projects of ground-based space infrastructure. It is associated with the possibility of special loads in the form of an air shock wave in the event of a launch abort, a fall of a fragment, an emergency shutdown of engines, an air shock wave from the indirect impact of nuclear weapons, seismic loads, accidental cargo falls, terrorist attacks, etc. Such impacts with a high degree of probability lead to damage to building structures and in the future, they need to be reinforced. These building structures must have survivability under special loads and deform without collapsing. Under the dynamic loading, the energy intensity of the bendable structures is important, to determine which it is necessary to know the magnitude of the acting force and deflections. The effective load in a wide class of problems refers to the initial data, and the determination of reliable values of the dynamic deflection of the bendable structure is an actual problem. The purpose of this study is to conduct a numerical and experimental investigation of the deflection of conventional and strengthened reinforced concrete structures under short-term dynamic loading. This study used the following research methods: measurements of deflections and loads by strain measurement, graphical analytic research using Microsoft Excel, numerical calculation in the environment of the Explicit Dynamics module of the Ansys software package. As a result of the study, experimental investigation of conventional and strengthened bendable reinforced concrete elements under short-term dynamic loading was carried out, the values of the effective force and deflections were obtained. The same experiment was modelled in the environment of the Explicit Dynamics module of the Ansys software package. A comparison of the deflection parameters was made, based on the results of numerical and physical experiments on the example of a specific design, which showed satisfactory convergence.

scholarly journals Report on the 3rd International Conference on Flood Recovery, Innovation and Response (FRIAR) 2012

2012 ◽  
Vol 43 (3) ◽  
Author(s):  
Daniele De Wrachien ◽  
David Proverbs
Keyword(s):  
Natural Disasters ◽  
Discharge Capacity ◽  
Heavy Precipitation ◽  
Flood Damage ◽  
Economic Losses ◽  
Natural Environments ◽  
Short Term ◽  
Loss Of Life ◽  
International Conference ◽  
Semiarid Areas

The terms flood or flooding are often used in different ways. According to the International Commission on Irrigation and Drainage (ICID), <em>flooding is defined as the overflowing or failing of the normal confines of a river, stream, lake, canal, sea or accumulation of water as a result of heavy precipitation where drains are lacking or their discharge capacity is exceeded</em>. The occurrence of floods is the most frequent amongst all natural disasters. Although flooding is a serious hazard in humid regions, it can also be devastating in semiarid areas, where high rates of runoff following storms produce widespread flood damage down valley. These hazards involve tragic loss of life, damage to buildings and natural environments, and massive short-term disruption to the lives of the affected population. One-third of the annual natural disasters and economic losses, and more than half of the respective victims are flood-related.

scholarly journals A survey of short-term and long-term stability of tube parameters in a mammography unit

2014 ◽  
Vol 29 (4) ◽  
pp. 321-325
Author(s):  
Jovica Praskalo ◽  
Jasna Davidovic ◽  
Biljana Kocic ◽  
Monika Zivkovic ◽  
Svetlana Pejovic
Keyword(s):  
Screening Program ◽  
Short Term ◽  
X Ray ◽  
Term Stability ◽  
Long Term Stability ◽  
Mammography Screening Program ◽  
The Republic ◽  
Set Up ◽  
The Given

In order to set up a successful mammography screening program in the Republic of Srpska, a Siemens Mammomat 1000 X-ray machine was selected for analysis as the said mammography system is widely used in clinical practice. The variations in tube parameters (specific air kerma, high-voltage accuracy and reproducibility, linearity between exposure and dose exposure time) were monitored over a five-year period, from 2008 to 2012. In addition, due to observed daily fluctuations for chosen parameters, a series of measurements were performed three times a day within a single-month period (mainly October 2012). The goal of such an experimental set up is to assess short-term and long-term stability of tube parameters in the given mammography unit and to make a comparison between them. The present paper shows how an early detection of significant parameter fluctuations can help eliminate irregularities and optimize the performance of mammography systems.

scholarly journals THE EVALUATION OF EFFECT OF VARIOUS OUTCOMES OF KIDNEY TRANSPLANTATION SURGERY ON ECONOMIC COSTS UNDER TREATMENT OF KIDNEYS CHRONIC DISEASE

2019 ◽  
Vol 62 (2) ◽  
pp. 60-67
Author(s):  
I. A. Lakman ◽  
A. A. Khalikova ◽  
Alexey A. Korzhenevskiy
Keyword(s):  
Kidney Transplantation ◽  
Human Life ◽  
Positive Outcome ◽  
Economic Losses ◽  
Economic Costs ◽  
Actual Problem ◽  
Transplantation Surgery ◽  
Number Of Patients ◽  
Heavy Burden ◽  
The Given

The growth of number of patients suffering with chronic kidneys disease became a reverse side of increasing of population life-span during recent decades. The treatment of the given pathology places a heavy burden on state economics. Nowadays, the implementation of kidneys transplantation is the main and only one mode of treatment of this disease permitting both to prolong human life and to significantly ameliorate its quality. The actual problem is the evaluation of economic costs occurring under both successful and unsuccessful outcomes of transplantation. The last one results in returning patient to dialysis procedure. The assessment was applied to direct and indirect expenses of kidney transplantation surgery and post-operational monitoring of patient, including application of dialysis. The expenses of treatment of patient with chronic kidneys disease per one person made annually up to: 1 266 967,88 rubles using dialysis therapy; 1 665 110,19 rubles using transplantation with positive outcome; 2 922 078,07 rubles using transplantation with unsuccessful outcome. Besides, in case of unsuccessful outcome of transplantation total amount of economic losses increased more on 91 343,77 rubles annually at the expense of decreasing of tax levy and increasing of disability compensation.

scholarly journals Options for solving the problem of parts of the Shelter object located outside the New Safe Confinement

2020 ◽  
Vol 19 (4) ◽  
pp. 57-65
Author(s):  
O. V. Balan ◽  
◽  
S. Gh. Brylka ◽  
V. V. Derengovskyi ◽  
V. V. Yehorov ◽  
...  
Keyword(s):  
Cost Effective ◽  
Radiation Condition ◽  
Design Stage ◽  
Final Decision ◽  
Building Structures ◽  
Short Term ◽  
Design Studies ◽  
Financial Costs ◽  
Work Area ◽  
Goals And Objectives

The parts of the Shelter object structures remained outside the New Safe Confinement (protruding parts) are considered in the article. The analysis of the building structures condition of the turbine hall and the deaerator stack protruding parts on the east and west sides is carried out and the necessity of works on strengthening and/or dismantling of bearing structures is confirmed. Possible variants of reconstruction of the Shelter object protruding parts are stated and the technological sequence of works is provided. The analysis of the possibilities of performing works in the conditions of functioning of the New Safe Confinement — Shelter object system proved that such activity is rather difficult task, which can cause significant physical and financial costs. As there is no guarantee of trouble-free operation of the building structures of the protruding parts during the entire service life of the New Safe Confinement, it is necessary to make every effort to solve this problem in the short term. The results of the analysis allow to choose the most advantageous solution to the goals and objectives for the safest and most cost/effective dismantling and/or strengthening of structures of protruding parts, taking into account a number of different criteria. These criteria may be different in nature, which allowed to build a generalized efficiency indicator for individual criteria with certain weights that determine the importance of each of the criteria for decision making. Based on the results of the analysis, these options can be considered equivalent. The final decision on the choice of the optimal variant for the Shelter object protruding parts reconstruction can be made after detailing the technological decisions at the design stage of protruding parts reconstruction and before the design studies of the radiation condition in the work area. The obtained information can be used as input data during the design of the reconstruction of the deaerator stack and the turbine hall parts of the Shelter object, which protrude beyond the New Safe Confinement.

Positioning Effect on Free Convection with an Elliptical Plate Placed in a Circular Enclosure

2020 ◽  
Vol 12 (8) ◽  
pp. 1054-1062
Author(s):  
Parth Patpatiya ◽  
Soumya ◽  
Bhavya Shaan ◽  
Bhavana Yadav
Keyword(s):  
Heat Transfer ◽  
Aspect Ratio ◽  
The Body ◽  
Elliptical Plate ◽  
Numerical Studies ◽  
First Case ◽  
Varied Temperature ◽  
Laminar Natural Convection ◽  
The Given ◽  
Plate System

In this analysis we have examined the process of the steady state laminar natural convection around heated elliptical plate with Rayleigh number 10^6 positioned inside a circular enclosure. The purpose of the numerical analysis is to analyze the behavior of isotherms, streamlines and heat transfer rate in enclosure plate system due to the variation in the position of elliptical plate (r/D =0.00, 0.05, and 0.2) and aspect ratio, where the given diameter of the enclosure is D and r is the distance between the centre of elliptical plate and centre of circle. Elliptical plate is inclined at different angles and results are summed up in relative manner. There are two cases, in first case aspect ratio a/D and b/D is varied and D is kept constant, whereas in second case aspect ratio a/D and b/D is kept constant and D is varied. Temperature difference between the enclosure and the inner body (i.e., temperature of inner body is kept high as compared to the enclosure) is maintained. Two dimensional study is followed by considering air as a fluid in enclosure. The effects of the Heat Transfer and Flow of Fluid are analyzed by the streamlines and isotherms plotted for the body placed inside enclosure. Value of local Nusselt number (Nu) is also plotted along the wall of elliptical plate and along the surface of the circular enclosure. For every aspect ratio isotherms and streamlines had been plotted. This work has been validated with various other numerical studies and was in good conciliation.

scholarly journals The development of climate security discourse in Japan

2020 ◽  
Vol 16 (1) ◽  
pp. 271-281
Author(s):  
Yasuko Kameyama ◽  
Keishi Ono
Keyword(s):  
Climate Change ◽  
Economic Losses ◽  
Specific Reference ◽  
Short Term ◽  
Weather Patterns ◽  
Security Discourse ◽  
Level Of Understanding ◽  
Change Problem ◽  
Indirect Economic Losses

AbstractAs the level of understanding about climate change has increased, the term “climate security” has been increasingly used in the rapidly growing literature on this subject. Although Japan has officially acknowledged the importance of tackling climate change, discussion of climate security has been almost nonexistent among Japanese governmental officials, politicians, and academics. Our aim was to trace discourses related to climate security in Japan to determine why so little exists in Japan and whether or not such discourse could suggest new areas for consideration to more comprehensively respond to the climate change problem. Because of different interpretations and uses of the term “climate security” in the existing literature, we first categorized existing approaches to climate security into four types and used this categorization to examine Japan’s discourse from these perspectives. Two of the approaches, namely “long-term irreversible planetary changes” and “short-term abrupt risks to individuals”, had been considered in Japan previously but without specific reference to the term climate security. The other two, “cause of conflict and violence” and “impacts to military and defense organizations”, however, had not been used and need to be included in discussions of climate change in Japan. Some of the topics not discussed in Japan include indirect economic losses of Japanese industries via supply chains, loss of Japan’s exclusive economic zone due to sea-level rise, and the potential inflow of refugees resulting from extreme weather patterns outside of Japan.

scholarly journals Towards Practical Application of Verticillium isaacii Vt305 to Control Verticillium Wilt of Cauliflower: Exploring Complementary Biocontrol Strategies

Plants ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1469
Author(s):  
Silke Deketelaere ◽  
Katrijn Spiessens ◽  
Sabien Pollet ◽  
Lien Tyvaert ◽  
Luc De Rooster ◽  
...  
Keyword(s):  
Verticillium Wilt ◽  
Seed Treatment ◽  
Field Experiments ◽  
Field Trials ◽  
Economic Losses ◽  
Green Manures ◽  
Control Effect ◽  
Short Term ◽  
Multiple Field ◽  
Green Manure Crops

Verticillium wilt is one of the most important diseases of cauliflower and can lead to serious economic losses. In this study, two complementary strategies were explored to employ the antagonistic capacity of Verticillium isaacii towards Verticillium wilt of cauliflower. The first strategy focused on introducing V. isaacii Vt305 by artificial inoculation of cauliflower plantlets at the nursery stage. Two inoculum types (spores and microsclerotia of V. isaacii Vt305) and different concentrations of microsclerotia were tested in greenhouse and field trials. Seed treatment with 500 microsclerotia seed−1 led to a satisfying biocontrol level of Verticillium wilt. In addition, the PHYTO-DRIP® system was successful in delivering the microsclerotia to cauliflower seeds. The second strategy relied on the stimulation of the natural V. isaacii populations by rotating cauliflower with green manures and potato. Four green manure crops and potato were tested during multiple field experiments. Although these crops seemed to stimulate the V. isaacii soil population, this increase did not result in a control effect on Verticillium wilt of cauliflower in the short term. Importantly, our results indicate that the use of green manures is compatible with the application of V. isaacii Vt305 as biocontrol agent of Verticillium wilt in cauliflower.

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