scholarly journals TWO-DIMENSIONAL SEICHE IN A BASIN SUBJECTED TO INCIDENT WAVES

2011 ◽  
Vol 1 (5) ◽  
pp. 10
Author(s):  
B. Le Mehaute

Seiche movements in lakes have for a long time been submitted to the calculations of the most competent scientists. Studies of seiche in open basins subject to the action of ocean waves are not so numerous and above all they are less rigorous. However the studies of Lord RAYLEIGH, HONDA, TERADA, YOSHIOA, ISITANI and HANSEN can be mentioned, and the important work by PROUDMAN on tide movements.(which often have a similar character to seiches), the studies of NEUMANN introducing the notion of hydraulic impedance, and those of LAMOEN on the theory of estuaries etc. More recently MC MOWN made theoretical and experimental studies at the Laboratoire Dauphinois d'Hydrauligue, for circular and square harbours. Formulae have been known for a long time giving the resonance period of long basins: basins which are sufficiently long for the oscillations to be considered only in the direction of the basin's length. By analogy with sound tubes two cases have been considered: that of basins completely closed and that of basins completely open. Standing wave; open basin; incident waves After a short review of the usefulness of maritime structures, particularly vertical wall breakwaters, long term observations of hydrogeological breaking on the bottom of Italy's Seas, as caused by the subaqueous source of fresh water, are discussed. The correlation between hydrogeological breaking and wave motion perturbation produced by compressed air or by oil is presented. These considerations are related to the observations of Admiral Alessandro Cialdi on the morphological breaking of waves above sand banks, thus producing calmness in the upper water. Therefore, it appears possible to establish a very suggestive analogy between the atomic disintegration of the transformation of potential energy of the oscillatory tide wave into kinematic energy of its components (because of breaking), in accordance with the disintegration of the circular motion.

2011 ◽  
Vol 1 (5) ◽  
pp. 11
Author(s):  
Agatino D'Arrigo

After a short review of the usefulness of maritime structures, particularly vertical wall breakwaters, long term observations of hydrogeological breaking on the bottom of Italy's Seas, as caused by the subaqueous source of fresh water, are discussed. The correlation between hydrogeological breaking and wave motion perturbation produced by compressed air or by oil is presented. These considerations are related to the observations of Admiral Alessandro Cialdi on the morphological breaking of waves above sand banks, thus producing calmness in the upper water. Therefore, it appears possible to establish a very suggestive analogy between the atomic disintegration of the transformation of potential energy of the oscillatory tide wave into kinematic energy of its components (because of breaking), in accordance with the disintegration of the circular motion.


2017 ◽  
Vol 19 (1) ◽  
pp. 49-53
Author(s):  
Rabia Farooq

Polycystic ovarian syndrome (PCOS) is a metabolic disease and a common endocrine system disorder among women of reproductive age. Infrequent or prolonged menstrual periods, excess hair growth, acne, and obesity can occur in women with PCOS. Early diagnosis and treatment along with weight loss may reduce the risk of long-term complications. Now a days PCOS is also the cause of infertility. India is PCOS capital of the world. PCOS management is necessary to reduce its long time complications.J MEDICINE Jan 2018; 19 (1) : 49-53


Author(s):  
Alfred O. Mueck

AbstractNew research on mechanisms of progestin effects in endometriosis treatment has been performed with dienogest (DNG), which has recently been launched in this regard. It is effective in the same low dosage of 2 mg/day, similar to the use of contraception and hormone therapy, whereas other progestogens (with the exception of dydrogesterone) must be given in much higher dosages to treat typical symptoms of endometriosis. This short review summarizes experimental studies on DNG. They demonstrate strong antiproliferative effects in endometrial and endometriotic cells or experimental endometriosis, as well as anti-inflammatory and antiangiogenic actions. By direct action on the ovarian folliculogenesis DNG lead to only modest suppression of estradiol production in contrast to the high-dosed progestogens or to gonadotropin releasing hormone (GnRH) agonists. These effects add to the well-known tolerability because DNG is very neutral regarding cardiovascular, metabolic or central action which also makes it suitable for long-term therapy.


2020 ◽  
Vol 64 (1-4) ◽  
pp. 1261-1268
Author(s):  
Shu Otani ◽  
Dang-Trang Nguyen ◽  
Kozo Taguchi

In this study, a portable and disposable paper-based microbial fuel cell (MFC) was fabricated. The MFC was powered by Rhodopseudomonas palustris bacteria (R. palustris). An activated carbon sheet-based anode pre-loaded organic matter (starch) and R. palustris was used. By using starch in the anode, R. palustris-loaded on the anode could be preserved for a long time in dry conditions. The MFC could generate electricity on-demand activated by adding water to the anode. The activated carbon sheet anode was treated by UV-ozone treatment to remove impurities and to improve its hydrophilicity before being loaded with R. palustris. The developed MFC could generate the maximum power density of 0.9 μW/cm2 and could be preserved for long-term usage with little performance degradation (10% after four weeks).


The results of experimental studies of masonry on the action of dynamic and static (short-term and long-term) loads are presented. The possibility of plastic deformations in the masonry is analyzed for different types of force effects. The falsity of the proposed approach to the estimation of the coefficient of plasticity of masonry, taking into account the ratio of elastic and total deformations of the masonry is noted. The study of the works of Soviet scientists revealed that the masonry under the action of seismic loads refers to brittle materials in the complete absence of plastic properties in it in the process of instantaneous application of forces. For the cases of uniaxial and plane stress states of the masonry, data on the coefficient of plasticity obtained from the experiment are presented. On the basis of experimental studies the influence of the strength of the so-called base materials (brick, mortar) on the bearing capacity of the masonry, regardless of the nature of the application of forces and the type of its stress state, is noted. The analysis of works of prof. S. V. Polyakov makes it possible to draw a conclusion that at the long application of the load, characteristic for the masonry are not plastic deformations, but creep deformations. It is shown that the proposals of some authors on the need to reduce the level of adhesion of the mortar to the brick for the masonry erected in earthquake-prone regions in order to improve its plastic properties are erroneous both from the structural point of view and from the point of view of ensuring the seismic resistance of structures. It is noted that the proposal to assess the plasticity of the masonry of ceramic brick walls and large-format ceramic stone with a voidness of more than 20% is incorrect, and does not meet the work of the masonry of hollow material. On the basis of the analysis of a large number of research works it is concluded about the fragile work of masonry.


Problems when calculating reinforced concrete structures based on the concrete deformation under compression diagram, which is presented both in Russian and foreign regulatory documents on the design of concrete and reinforced concrete structures are considered. The correctness of their compliance for all classes of concrete remains very approximate, especially a significant difference occurs when using Euronorm due to the different shape and sizes of the samples. At present, there are no methodical recommendations for determining the ultimate relative deformations of concrete under axial compression and the construction of curvilinear deformation diagrams, which leads to limited experimental data and, as a result, does not make it possible to enter more detailed ultimate strain values into domestic standards. The results of experimental studies to determine the ultimate relative deformations of concrete under compression for different classes of concrete, which allowed to make analytical dependences for the evaluation of the ultimate relative deformations and description of curvilinear deformation diagrams, are presented. The article discusses various options for using the deformation model to assess the stress-strain state of the structure, it is concluded that it is necessary to use not only the finite values of the ultimate deformations, but also their intermediate values. This requires reliable diagrams "s–e” for all classes of concrete. The difficulties of measuring deformations in concrete subjected to peak load, corresponding to the prismatic strength, as well as main cracks that appeared under conditions of long-term step loading are highlighted. Variants of more accurate measurements are proposed. Development and implementation of the new standard GOST "Concretes. Methods for determination of complete diagrams" on the basis of the developed method for obtaining complete diagrams of concrete deformation under compression for the evaluation of ultimate deformability of concrete under compression are necessary.


Mediaevistik ◽  
2020 ◽  
Vol 32 (1) ◽  
pp. 11-53
Author(s):  
Bernard S. Bachrach

During the first thirty-three years of his reign as king of the Franks, i.e., prior to his coronation as emperor on Christmas day 800, Charlemagne, scholars generally agree, pursued a successful long-term offensive and expansionist strategy. This strategy was aimed at conquering large swaths of erstwhile imperial territory in the west and bringing under Carolingian rule a wide variety of peoples, who either themselves or their regional predecessors previously had not been subject to Frankish regnum.1 For a very long time, scholars took the position that Charlemagne continued to pursue this expansionist strategy throughout the imperial years, i.e., from his coronation on Christmas Day 800 until his final illness in later January 814. For example, Louis Halphen observed: “comme empereur, Charles poursuit, sans plus, l’oeuvre entamée avant l’an 800.”2 F. L. Ganshof, who also wrote several studies treating Charlemagne’s army, was in lock step with Halphen and observed: “As emperor, Charlemagne pursued the political and military course he had been following before 25 December 800.”3


1984 ◽  
Vol 16 (3-4) ◽  
pp. 623-633
Author(s):  
M Loxham ◽  
F Weststrate

It is generally agreed that both the landfill option, or the civil techniques option for the final disposal of contaminated harbour sludge involves the isolation of the sludge from the environment. For short time scales, engineered barriers such as a bentonite screen, plastic sheets, pumping strategies etc. can be used. However for long time scales the effectiveness of such measures cannot be counted upon. It is thus necessary to be able to predict the long term environmenttal spread of contaminants from a mature landfill. A model is presented that considers diffusion and adsorption in the landfill site and convection and adsorption in the underlaying aquifer. From a parameter analysis starting form practical values it is shown that the adsorption behaviour and the molecular diffusion coefficient of the sludge, are the key parameters involved in the near field. The dilution effects of the far field migration patterns are also illustrated.


Author(s):  
John Toye

This book provides a survey of different ways in which economic sociocultural and political aspects of human progress have been studied since the time of Adam Smith. Inevitably, over such a long time span, it has been necessary to concentrate on highlighting the most significant contributions, rather than attempting an exhaustive treatment. The aim has been to bring into focus an outline of the main long-term changes in the way that socioeconomic development has been envisaged. The argument presented is that the idea of socioeconomic development emerged with the creation of grand evolutionary sequences of social progress that were the products of Enlightenment and mid-Victorian thinkers. By the middle of the twentieth century, when interest in the accelerating development gave the topic a new impetus, its scope narrowed to a set of economically based strategies. After 1960, however, faith in such strategies began to wane, in the face of indifferent results and general faltering of confidence in economists’ boasts of scientific expertise. In the twenty-first century, development research is being pursued using a research method that generates disconnected results. As a result, it seems unlikely that any grand narrative will be created in the future and that neo-liberalism will be the last of this particular kind of socioeconomic theory.


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