Water pressure in a tank caused by a simulated earthquake*

1934 ◽  
Vol 24 (1) ◽  
pp. 1-32
Author(s):  
Leander M. Hoskins ◽  
Lydik S. Jacobsen

Abstract.— The theoretical interpretation of the experiments rests on the solution of the hydrodynamical problem of determining the motion and pressure throughout the body of water in a rectangular tank to which is given an arbitrary small oscillation parallel to its length. The solution is similar to that given by H. M. Westergaard for a channel of infinite length, reducing to Westergaard's solution as a limiting case. It is shown that if the length of the tank is two and one-half times the depth of the water, the total pressure on one end is about 4 per cent less than for a channel of infinite length. In order that the accelerative force due to the inertia of the body of water may be measured, the tank is mounted on rollers on a shaking table in such a way that, with negligible friction, the motion of the shaking table is communicated to the tank by means of an elastic connection which also serves the function of a spring dynamometer. The motion of the tank is therefore never exactly the same as the motion of the shaking table. With increasing rigidity of the dynamometer, the motions of the tank and the table become more and more alike. If the tank is empty of water, the force measured by the dynamometer is due wholly to the inertia of the tank together with any solid bodies attached to it; but if the tank contains water, the force is due in part to the varying pressure of the water upon the ends of the tank. By comparing the dynamometer record when water is present with records obtained when the water is replaced by solid bodies of known mass, it is possible to determine what part of the force acting on the dynamometer is due to water pressure. The motion of the shaking table is produced by an elastic impact of a pendulum moving with known velocity against a bumper spring on the shaking table. The starting motion during the impact time interval is fairly simple, and the subsequent motion is a free, damped vibration. The motion can be produced experimentally again and again with great accuracy, and, inasmuch as the starting motion lasts for a relatively short time, the system of reflected, gravitational waves from the ends of the tank does not come into existence for a time relatively long as compared to the impact time interval. This type of motion is probably the simplest element of actual earthquake motions which it is feasible to reproduce with repeated accuracy in the laboratory. The maximum acceleration of the tank during the impact interval ranged from 0.7 to 1.2 times that of gravity. Altogether seven different experimental combinations of three table periods and three tank-dynamometer periods were used. If the experimental combinations be related to conditions existing in nature, the period of the table corresponds to the period of the earthquake motion, and the frequency of the tank-dynamometer system corresponds approximately to the frequency of the free vibration of a dam. The experimental results show a satisfactory agreement with the theory. If the ratio of the experimental value of the equivalent water load to the theoretical value of the equivalent water load be called W′/W, the average of eighty-three observations on the tank with a single compartment gave W′/W = 0.78, and the average of 104 observations on the tank with two compartments gave W′/W = 0.85. One of the obvious reasons for the ratio of W′/W being smaller than unity is the lack of rigidity of the tanks. Not only the total hydrodynamic load, but also the distribution of the pressure on the ends of the tank was measured, and a satisfactory verification of the theory in this regard has been obtained.

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Dan B. Marghitu ◽  
Seung Lee

In this study, the experimental and the simulation results for a planar free link impacting a granular medium are analyzed. The resistance force of the granular medium on the body from the moment of the impact until the body stops is very important. Horizontal and vertical static resistance forces developed by theoretical and empirical approaches are considered. The penetrating depth of the impacting end of the free link increases with the increase of the initial impacting velocity. We define the stopping time as the time interval from the moment of impact until the vertical velocity of the link end is zero. The stopping time of the end decreases as the initial velocity increases. The faster the end of the link impacts the surface of the granular medium, the sooner it will come to a stop. This phenomenon involves how rapidly a free link strikes the granular medium and how it slows down upon contact.


2019 ◽  
Vol 11 (1) ◽  
pp. 155-157
Author(s):  
D. Divyalakshmi ◽  
N. Kumaravelu ◽  
C. Balan ◽  
Thanga.Thamil Vanan ◽  
P. Tensingh Gnanaraj

Pig rearing on concentrate feed may not be economical because of higher market price of raw materials. The alternative source could be the use of swill feeding. Consequently, the impact of the swill feed on the backfat thickness and body measurements calls for investigation against any other alternative feed.  Hence in the present study, an attempt has been made to compare the body measurements and backfat thickness in fattener piglets which were fed with swill feed (T1) vs. Those fed with chocolate cream waste supplemented with swill feed (T2). The statistical analysis of the data obtained in the present study revealed that there was highly significant (P?0.01) difference between body weight gain and backfat thickness (layer I and II) of both the group of piglets which were taken for trial starting from three months of age till five months of age. However, not significant difference (P?0.05) was noticed for body length and chest girth except in the pigs of 150 days age group. This study indicates that swill feed supplemented with chocolate cream waste could be used to reduce the feed cost since higher weight gain is achieved in a shorter time interval, increasing body measurements and backfat thickness compared to swill feed (T1) group of piglets.


Author(s):  
Gustavo Simão Rodrigues ◽  
Hans Ingo Weber ◽  
Larissa Driemeier

There are many models of impact used to predict the post-impact conditions of a system and all of them are based on Hertz’s theory, dated from the nineteenth century, where the repulsive force is proportional to the deformation of the bodies under contact and may also be proportional to the rate of deformation. The objective of this work is to analyze the behavior of the bodies during impact using some contact models and compare the results to a Finite Element Method model. The main parameters which will be evaluated are the body velocities, the contact force and the deformation of the bodies. An advantage of using the Finite Element Method is the possibility to apply plastic deformation to the model according to material definition. In the present study, it will be used Johnson–Cook plasticity model where the parameters are obtained based on empirical tests of real materials. Thus, it is possible to compare the behavior of elastic and plastic numerical models with the finite element model and to verify how these models reproduce the impact between solid bodies.


2018 ◽  
Vol 15 (2) ◽  
pp. 1-20
Author(s):  
Sabri Embi ◽  
Zurina Shafii

The purpose of this study is to examine the impact of Shariah governance and corporate governance (CG) on the risk management practices (RMPs) of local Islamic banks and foreign Islamic banks operating in Malaysia. The Shariah governance comprises the Shariah review (SR) and Shariah audit (SA) variables. The study also evaluates the level of RMPs, CG, SR, and SA between these two type of banks. With the aid of SPSS version 20, the items for RMPs, CG, SR, and SA were subjected to principal component analysis (PCA). From the PCA, one component or factor was extracted each for the CG, SR, and RMPs while another two factors were extracted for the SA. Primary data was collected using a self-administered survey questionnaire. The questionnaire covers four aspects ; CG, SR, SA, and RMPs. The data received from the 300 usable questionnaires were subjected to correlation and regression analyses as well as an independent t-test. The result of correlation analysis shows that all the four variables have large positive correlations with each other indicating a strong and significant relationship between them. From the regression analysis undertaken, CG, SR, and SA together explained 52.3 percent of the RMPs and CG emerged as the most influential variable that impacts the RMPs. The independent t-test carried out shows that there were significant differences in the CG and SA between the local and foreign Islamic banks. However, there were no significant differences between the two types of the bank in relation to SR and RMPs. The study has contributed to the body of knowledge and is beneficial to academicians, industry players, regulators, and other stakeholders.


2020 ◽  
pp. 15-18
Author(s):  
Inna R. Kilmetova ◽  
◽  
Igor A. Rodin ◽  
Nazira I. Khayrullina ◽  
Nikolay G. Fenchenko ◽  
...  

Summary. The disbalanced feeding and the uneven distribution of micro- and macroelements in the environment leads to a trace element, in particular hypomelanosis. To accelerate the growth and preservation of young farm animals include in the diet of various biological additives and drugs, which include selenium. For stimulation of weight gain in the livestock industry, as well as for the prevention and treatment of pathological processes in addition to micro - and macrouse amino acids, primarily methionine. The aim of this work was to study the influence of composition of DAFS-25+Polizon on morpho-biochemical parameters of blood and functional state of the liver in fattening bulls of black-motley breed in the conditions of the Republic of Bashkortostan. Experiments using were conducted on bull-calves of black-motley breed of the properties in the properties age from 6 to 15 months. The first experimental group during the experiment was additionally given the composition of DAFS-25+Polizon at a dose of 2 mg/kg, the animals of the control group received a standard diet. To assess the impact of the composition DAFS-25+Polizon on metabolism cattle studied morphological and biochemical indicators of blood and conducted histological examination of the liver. It is established that the use of the composition of DAFS-25+Polizon at a dose of 2 mg/kg increases the number of erythrocytes and hemoglobin in the experimental group and reduces the amount of white blood cells. The serum content of total protein, phosphorus and calcium increases in the group of experimental animals. Microscopic examination of the liver revealed no changes in the structure of the organ and hepatocytes in the experimental group, whereas in the control group hemodynamic disorders and dystrophic changes in liver cells were observed. Thus, the use of the composition DAFS-25+Polizon at a dose of 2 mg/kg of live weight in fattening bulls black-and-white breed contributes to the increase of redox processes in the body, stimulation of metabolism, prevent the development of liver disorders of cellular mechanisms of metabolism, optimizes the structure of the liver, which generally provides higher productivity.


Author(s):  
Mohammed Ibrahim ◽  
Alaa Zaky ◽  
Mohsen Afouna ◽  
Ahmed Samy

Carrier erythrocytes are emerging as one of the most promising biological drug delivery systems investigated in recent decades. Beside its biocompatibility, biodegradability and ability to circulate throughout the body, it has the ability to perform extended release system of the drug for a long period. The ultimate goal of this study is to introduce a new carrier system for Salbutamol, maintaining suitable blood levels for a long time, as atrial to resolve the problems of nocturnal asthma medication Therefore in this work we study the effect of time, temperature as well as concentration on the loading of salbutamol in human erythrocytes to be used as systemic sustained release delivery system for this drug. After the loading process is performed the carrier erythrocytes were physically and cellulary characterized. Also, the in vitro release of salbutamol from carrier erythrocytes was studied over time interval. From the results it was found that, human erythrocytes have been successfully loaded with salbutamol using endocytosis method either at 25 Co or at 37 Co . The highest loaded amount was 3.5 mg/ml and 6.5 mg/ml respectively. Moreover, the percent of cells recovery is 90.7± 1.64%. Hematological parameters and osmotic fragility behavior of salbutamol loaded erythrocytes were similar that of native erythrocytes. Scanning electron microscopy demonstrated that the salbutamol loaded cells has moderate change in the morphology. Salbutamol releasing from carrier cell was 43% after 36 hours in phosphate buffer saline. The releasing pattern of the drug from loaded erythrocytes showed initial burst release in the first hour followed by a very slow release, obeying zero order kinetics. It concluded that salbutamol is successfully entrapped into erythrocytes with acceptable loading parameters and moderate morphological changes, this suggesting that erythrocytes can be used as prolonged release carrier for salbutamol.


Author(s):  
M. S. Bugaeva ◽  
O. I. Bondarev ◽  
N. N. Mikhailova ◽  
L. G. Gorokhova

Introduction. The impact on the body of such factors of the production environment as coal-rock dust and fluorine compounds leads to certain shift s in strict indicators of homeostasis at the system level. Maintaining the relative constancy of the internal environment of the body is provided by the functional consistency of all organs and systems, the leading of which is the liver. Organ repair plays a crucial role in restoring the structure of genetic material and maintaining normal cell viability. When this mechanism is damaged, the compensatory capabilities of the organ are disrupted, homeostasis is disrupted at the cellular and organizational levels, and the development of the main pathological processes is noted.The aim of the study is to compare the morphological mechanisms of maintaining structural homeostasis of the liver in the dynamics of the impact on the body of coal-rock dust and sodium fluoride.Materials and methods. Experimental studies were conducted on adult white male laboratory rats. Features of morphological mechanisms for maintaining structural homeostasis of the liver in the dynamics of exposure to coal-rock dust and sodium fluoride were studied on experimental models of pneumoconiosis and fluoride intoxication. For histological examination in experimental animals, liver sampling was performed after 1, 3, 6, 9, 12 weeks of the experiment.Results. The specificity of morphological changes in the liver depending on the harmful production factor was revealed. It is shown that chronic exposure to coal-rock dust and sodium fluoride is characterized by the development of similar morphological changes in the liver and its vessels from the predominance of the initial compensatory-adaptive to pronounced violations of the stromal and parenchymal components. Long-term inhalation of coal-rock dust at 1–3 weeks of seeding triggers adaptive mechanisms in the liver in the form of increased functional activity of cells, formation of double-core hepatocytes, activation of immunocompetent cells and endotheliocytes, ensuring the preservation of the parenchyma and the general morphostructure of the organ until the 12th week of the experiment. Exposure to sodium fluoride leads to early disruption of liver compensatory mechanisms and the development of dystrophic changes in the parenchyma with the formation of necrosis foci as early as the 6th week of the experiment.Conclusions. The study of mechanisms for compensating the liver structure in conditions of long-term exposure to coal-rock dust and sodium fluoride, as well as processes that indicate their failure, and the timing of their occurrence, is of theoretical and practical importance for developing recommendations for the timely prevention and correction of pathological conditions developing in employees of the aluminum and coal industry.The authors declare no conflict of interests.


Author(s):  
Elena A. Beigel ◽  
Natalya G. Kuptsova ◽  
Elena V. Katamanova ◽  
Oksana V. Ushakova ◽  
Oleg L. Lakhman

Introduction. Occupational chronic obstructive pulmonary disease (COPD) is one of the leading nosological forms of occupational respiratory disease. Numerous studies have shown high effectiveness of the combination of indacaterol/glycopyrronium (Ultibro®breezhaler®) on the impact on clinical and functional indicators in the treatment of COPD in General practice.The aim of the investigation the case of occupational COPD with the analysis of the dynamics of functional indicators, tolerance to physical load and evaluation of the quality of life of workers engaged in aluminum production by using combination of indacaterol/glycopyrronium.Materials and methods. The random sampling method included 20 men, workers of aluminum production, with the established diagnosis of professional COPD at the age of 40 to 60 years. The survey was conducted (Borg scale, medical Research Council scale (mMRC) and COPD Assessment Test (CAT). Functional methods of studies were conducted: spirometry, body plethysmography, electrocardiography (ECG) and the six-minute stepper test (6-MST).Results. Against the background of 8 weeks of therapy, the volume of forced exhalation for 1 minute (FEV1) increased by 14.7% and amounted to 67.90% of the due values, the forced vital capacity of the lungs (FVC) increased by 11.3% and amounted to 76.95% of the due. According to the body plethysmography (BPG) is set to decrease in residual lung volume on average by 13.4% and static hyperinflation, confirmed by the decrease in functional residual volume (FRV) of 18.8%. During the study period increased physical activity of patients. The average difference between the distance traveled in the six-minute step test before and after treatment was 58.8 m. The analysis of personal data showed that the quality of life of patients improved, the total score in the questionnaire CAT at the beginning of the study was 16.9 points, and after 8 weeks decreased by 63% and amounted to 10.7 points.Conclusions: The Results indicate a positive effect of combination therapy with indacaterol/glycopyrronium on the course and progression of occupational COPD.


2003 ◽  
Vol 9 (1) ◽  
pp. 175-188 ◽  
Author(s):  
Patricia Farrell ◽  
Murari Suvedi

The purpose of this study is to analyze the reported or perceived impact of studying in Nepal on student’s academic program, personal development and intellectual development. The study draws upon adult learning theory to analyze survey instrument data, interviews, and case studies to discern the impact of the program on college students and to contribute to the body of longitudinal research on U.S. study abroad programs.


2020 ◽  
Vol 26 (3) ◽  
pp. 358-362 ◽  
Author(s):  
Ioannis P. Kosmas ◽  
Antonio Malvasi ◽  
Daniele Vergara ◽  
Ospan A. Mynbaev ◽  
Radmila Sparic ◽  
...  

: In recent years, the development of Assisted Reproductive Technique, the egg and embryo donation changed substantially the role of the uterus in recent years. It provided a higher chance for a pregnancy even in women over 45 years or post-menopause. In fact, the number of aged patients and in peri/post-menopause in pregnancy is nowadays increasing, but it increases obstetrical and neonatal related problems. The human uterus is richly innervated and modified especially during pregnancy and labor, and it is endowed with different sensory, parasympathetic, sympathetic and peptidergic neurofibers. They are differently distributed in uterine fundus, body and cervix, and they are mainly observed in the stroma and around arterial vessel walls in the myometrial and endometrial layers. Many neurotransmitters playing important roles in reproductive physiology are released after stimulation by adrenergic or cholinergic nerve fibers (the so called sympathetic/parasympathetic co-transmission). Immunohistochemical study demonstrated the localization and quantitative distribution of neurofibers in the fundus, the body and cervix of young women of childbearing age. : Adrenergic and cholinergic effects of the autonomous nervous system are the most implicated in the uterine functionality. In such aged women, the Adrenergic and AChE neurofibers distribution in the fundus, body and cervix is progressively reduced by increasing age. Adrenergic and AChE neurotransmitters were closely associated with the uterine arteries and myometrial smooth muscles, and they reduced markedly by ageing. The Adrenergic and AChE neurofibers decreasing has a dramatical and negative impact on uterine physiology, as the reduction of pregnancy chance and uterine growth, and the increase of abortion risk and prematurity.


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