scholarly journals The Influence of Current on the Height of Wind Wave Run-Up: A comparison of experimental results with the Czech National Standard

2012 ◽  
Vol 60 (3) ◽  
pp. 174-184 ◽  
Author(s):  
Jaromir Riha ◽  
Miroslav Spano

The Influence of Current on the Height of Wind Wave Run-Up: A comparison of experimental results with the Czech National StandardOne of the basic questions related to the safety of dikes and river levees is the size of the freeboard. One of the important parameters for freeboard design is the height of waves and wave run-up on levee slopes. Routine and standardised calculations of wave run-up deal with the freeboards of dams where wind waves originate on the still water of the reservoir. In the case of running water in streams (thereinafter only "currents") the effect of wave and current interaction on wave run-up is usually not taken into account due to the lack of reliable knowledge regarding the phenomenon. In the Czech Republic this question is topical in the case of large rivers such as the Elbe, the Vltava and the Morava. Within the framework of the projects Hydralab III and NAZV QI 92A139, hydraulic research and further analysis focused on wave run-up as a result of the combination of current and wind wave parameters were performed. The laboratory research was carried out in a hydraulic flume with a wavemaker on the right bank and a levee with a slope of 1:3 installed on the left bank opposite the wavemaker. Waves were generated both perpendicular and oblique to the levee axis; the angle of oblique wave attack varied within the range of ± 30°. The aim of this paper is to compare the results of the mentioned research with recommendations mentioned in the Czech National Standard CSN 75 0255Calculation of wave effects on water structuresand to quantify the effect of current on the wave run-up height.

Author(s):  
WILLIAM GARDENER

Prince Henri d'Orleans, precluded by French law from serving his country in the profession of arms, had his attention turned early towards exploration. In 1889, accompanied by the experienced traveller Gabriel Bonvalet, he set out from Paris to reach Indo-China overland by way of Central Asia, Tibet and western and south western China. The journey made contributions in the problems of the whereabouts of Lap Nor and the configuration of the then unexplored northern plateau of Tibet; and in botany it produced some species new to science. The party reached Indo-China in 1890. In 1895, having organised an expedition better equipped for topographical survey and for investigations in the fields of natural history and ethnography, Prince Henri set out from Hanoi with the intention of exploring the Mekong through the Chinese province of Yunnan. After proceeding up the left bank of the Salween for a brief part of its course and then alternating between the right and left banks of the Mekong as far up as Tzeku, the party found it advisable to enter Tibet in a north westerly direction through the province of Chamdo and instead crossed the south eastern extremity of the country, the Zayul, by a difficult track which led them to the country of the Hkamti Shans in present day Upper Burma, and thence to India completing a journey of 2000 miles, "1500 of which had been previously untrodden" (Prince Henri). West of the Mekong, the journey established that the Salween, which some geographers had claimed took its rise in or near north western Yunnan, in fact rose well north in Tibet, and that, contrary to previous opinions, the principal headwater of the Irrawaddy rose no further north than latitude 28°30'. Botanical collections were confined to Yunnan, where the tracks permitted mule transport, and they produced a number of species new to science and extended the range of distribution of species already known.


2019 ◽  
Vol 70 (11) ◽  
pp. 3903-3907
Author(s):  
Galina Marusic ◽  
Valeriu Panaitescu

The paper deals with the issues related to the pollution of aquatic ecosystems. The influence of turbulence on the transport and dispersion of pollutants in the mentioned systems, as well as the calculation of the turbulent diffusion coefficients are studied. A case study on the determination of turbulent diffusion coefficients for some sectors of the Prut River is presented. A new method is proposed for the determination of the turbulent diffusion coefficients in the pollutant transport equation for specific sectors of a river, according to the associated number of P�clet, calculated for each specific area: the left bank, the right bank and the middle of the river.


2020 ◽  
Vol 2 (1) ◽  
pp. 115-130
Author(s):  
R. R. Palekha ◽  

Introduction. Right understanding is the most live, interesting and, at the same time, the uncertain and changeable area of researches which takes the central place as in the general theory of the right, and gains the increasing value in industry jurisprudence that is connected with its considerable teoretiko-methodological and applied potential which is shown in spheres of lawmaking and law-enforcement activity. Thus, right understanding represents research tools of the subject of knowledge which allow to study all range legal and, the based on them, state phenomena for the purpose of obtaining reliable knowledge of state and legal reality. In this regard integrative approach in right understanding which has rich history of the formation and development is of special interest, allows to perceive the right as integrally complete phenomenon, as much as possible retrieves its regulatory abilities and, provides achievement of criteria of scientific research: comprehensiveness, objectivity, historicism. Materials and Methods. In article an attempt of the analysis of integrative approach in right understanding from a position of history of origin of his ideas and assessment of the current state is made. A result of studying of scientific literature, generalization and comparison of the different points of view fat formulation of author’s determination of category “right understanding” and submission of the evidence-based integrative theory of right understanding which as much as possible conforms to requirements of time and has essential regulatory and guarding potential. Results. In article the category right understanding is comprehensively considered, different integrative theories of right understanding from a position of their origin and development are submitted, the value of modern integrative approach in right understanding is shown, perspectives of its further development are evaluated. Discussion and Conclusion. The author comes to the conclusion about the theoretical and methodological consistency and inevitability of the integrative approach in law understanding, which acts as a scientifically grounded type of legal thinking capable of comprehending the law on a truly scientific basis.


2008 ◽  
Vol 68 (4) ◽  
pp. 799-805 ◽  
Author(s):  
EK. Resende ◽  
DKS. Marques ◽  
LKSG. Ferreira

The "tucunaré", Cichla piquiti, an exotic Amazonian fish has become established along the left bank of the Paraguay River in the Pantanal. It was introduced by escaping from culture ponds in the Upper Piquiri River and spread downstream, along the lateral flooded areas of that river, continuing through the clear waters of the left bank of the Paraguay River and reaching south as far as the Paraguai Mirim and Negrinho rivers. Adult spawners have been found in the region, meaning that it is a self-sustained population. Reproduction occurs in the period of low waters. They were found feeding on fishes of lentic environments belonging to the families Characidae, Cichlidae and Loricariidae. Until the end of 2004, its distribution was restricted to the left bank of the Paraguay River, but in March 2005, some specimens were found on the right bank, raising a question for the future: what will be the distribution area of the tucunaré in the Pantanal? Information about its dispersion is increasing: it is known to be in the Tuiuiú Lake, Pantanal National Park and in the Bolivian Pantanal, all of them on the right bank of the Paraguay River. The hypothesis that the "tucunaré" could not cross turbid waters, such as in the Paraguay River, was refuted by these recent findings. Possibly, the tucunaré's capacity to lay more than one batch of eggs in a reproductive period, as well as its care of eggs and young, lead them to establish themselves successfully in new environments, as has been observed in the Pantanal and other localities.


2017 ◽  
Vol 34 (10) ◽  
pp. 2129-2139 ◽  
Author(s):  
Naohisa Takagaki ◽  
Satoru Komori ◽  
Mizuki Ishida ◽  
Koji Iwano ◽  
Ryoichi Kurose ◽  
...  

AbstractIt is important to develop a wave-generation method for extending the fetch in laboratory experiments, because previous laboratory studies were limited to the fetch shorter than several dozen meters. A new wave-generation method is proposed for generating wind waves under long-fetch conditions in a wind-wave tank, using a programmable irregular-wave generator. This new method is named a loop-type wave-generation method (LTWGM), because the waves with wave characteristics close to the wind waves measured at the end of the tank are reproduced at the entrance of the tank by the programmable irregular-wave generator and the mechanical wave generation is repeated at the entrance in order to increase the fetch. Water-level fluctuation is measured at both normal and extremely high wind speeds using resistance-type wave gauges. The results show that, at both wind speeds, LTWGM can produce wind waves with long fetches exceeding the length of the wind-wave tank. It is observed that the spectrum of wind waves with a long fetch reproduced by a wave generator is consistent with that of pure wind-driven waves without a wave generator. The fetch laws between the significant wave height and the peak frequency are also confirmed for the wind waves under long-fetch conditions. This implies that the ideal wind waves under long-fetch conditions can be reproduced using LTWGM with the programmable irregular-wave generator.


Author(s):  
V. P. Tkach ◽  
O. V. Kobets ◽  
M. G. Rumiantsev

The forest site capacity using was quantitatively assessed for the stands of the main forest-forming species of Ukraine, Scots pine and common oak, taking into account natural zones and forest types. The tables of productivity of modal and highly productive pine and oak stands have been developed. It has been found that the stands use an average of 50–75 % of the forest site capacity of lands. The average weighted value of the capacity used by pine forests was 68–76 % in the Polissya zone, 70–78 % and 68–73 % in the Right-bank and Left-bank Forest-Steppe zones respectively, and 54–78 % in the Steppe zone. For oak stands, the value was 71–75 % and 63–71 % for the Right-bank and Left-bank Forest-Steppe zones respectively and 65–75 % for the Steppe zone. The basis for increasing the productivity of forests was confirmed to be the differentiation of forest management systems and individual forestry activities on a zonal and typological basis.


2021 ◽  
Vol 12 (3) ◽  
pp. 737-747
Author(s):  
Jones Fiegenbaum ◽  
Marina Schmidt Dalzochio ◽  
Eduardo Périco ◽  
Neli Teresinha Galarce Machado

The Jê archeology has witnessed in the last decades a significant increase in information on the pattern of settlement, subsistence, mobility and ceremonial practices as a result of major projects developed in the South Brazilian Plateau. With the beginning of a systemic and procedural view in archeology, interdisciplinary studies in archaeological research are directed to the study on the understanding of human relations with the environment. Between the basins of the Forqueta and Guaporé Rivers, both tributaries of the right bank of the Taquari/Antas River, twenty-one archaeological sites were found with the presence of pit houses associated with Jê groups. Of the twenty-one areas of identified pit houses, nineteen are in areas close to wetlands. In an interdisciplinary perspective, we seek to understand the reasons why Jê groups established settlements close to wetlands. Six criteria were analyzed regarding the installation of pit houses and the proximity to wetlands, namely hydrography, distance from rivers with running water, clinography, terrain slope, hypsometry, altitude in relation to sea level, soils, soil quality, distance from wetlands, and phytoecological region (vegetation cover). The patterns of occupation of Jê groups were analyzed using the Principal Component Analysis technique on the variables presented.


1988 ◽  
Vol 1 (21) ◽  
pp. 36 ◽  
Author(s):  
Hendrick L. Tolman

Effects of instationary depths and currents in tides on shelf seas on wind wave propagation are investigated using two numerical models in two academical situations representing shelf sea conditions. It is shown that changes in absolute frequency, which are induced by the instationarity of depth and current, are significant in contrast to what is usually assumed. If these changes are neglected large and unpredictable errors may occur in calculated changes of wavenumber and amplitude.


2021 ◽  
Vol 40 (3) ◽  
pp. 155-168
Author(s):  
D. G. Diachenko

The paper is devoted to the Raiky culture in the Middle Dnieper. It reveals major issues of the phenomenon of Raiky culture and their possible solutions considering the achievements of Ukrainian archeologists in this field. The genesis, chronology and features of the development of material culture of the Raiky sites in the 8th—9th centuries of the right-bank of the Dnieper are analyzed. In general the existence of the Raiky culture in the Middle Dnieper region can be described as follows. It was formed in first half of the 8th century in the Tiasmyn basin. The first wheel-made pottery has begun to manufacture quite early, from the mid-8th century (probably at the beginning of the third quarter). At the first stage, the early vessels have imitated the hand-made Raiky forms as well as the Saltovo-Mayaki imported vessels. Significant development of the material culture occurs during the second half of the 8th century. At the same time, the movement of the people of Raiky culture and the population of the sites of Sаkhnivka type has begun in the northern direction which was marked by the appearance of the Kaniv settlement, Monastyrok, and possibly Buchak. This stage is characterized by the syncretism both in the ceramic complex and in the features of design of the heating structures. Numerous influences of the people of Volyntsevo culture (and through them – of Saltovo-Mayaki one) are recorded in the Raiky culture. It is observed not only in direct imports but also in the efforts of the Raiky population to imitate the pottery of Volyntsevo and Saltovo-Mayaki cultures, however, based on their own technological capabilities. The nature of the relationship between the bearers of these cultures is still interesting. The population of Raiky accepts the imported items of Saltovo-Mayaki and Volyntsevo cultures, tries to imitate high-quality pottery of them, and even one can see the peaceful coexistence of two cultures in one settlement — Monastyrok, Buchak, Stovpyagy. However, the reverse pulses are absent. There are no tendencies to assimilate each other. Although, given the number and size of the sites, the numerical advantage of the Volyntsevo population in the region seems obvious. There is currently no answer to this question. The first third of the 9th century became the watershed. The destruction of the Bytytsia hill-fort and the charred ruins to which most of the settlements of the Volyntsevo culture has turned, is explained in the literature by the early penetration of Scandinavians into the region or as result of the resettlement of Magyars to the Northern Pontic region. In any case, this led to a change in the ethnic and cultural situation in the Dnieper basin. According to some researchers, the surviving part of the population of Volyntsevo culture migrated to the Oka and Don interfluve. For some time, but not for long, the settlements of Raiky culture remained abandoned. Apparently, after the stabilization of situation, the residents have returned which is reflected by the reconstruction of the Kaniv settlement and Monastyrok; in addition, on the latter the fortifications have been erected. The final stage of the existence of culture is characterized by contacts with the area of the left bank of Dnieper, the influx of the items of the «Danube circle», as well as the rapid development of the forms of early wheel-made pottery. The general profiling of vessels and design of the rim became more complicated, the rich linear-wavy ornament which covers practically all surface of the item became characteristic. This suggests the use of a quick hand wheel which has improved the symmetry of the vessels, as well as permitted to create the larger specimens. The evolution of the early wheel-made ceramic complex took place only by a variety of forms, however, technological indicators (dough composition, firing, density and thickness of vessel walls) indicate the actual invariability and sustainability of the manufacture tradition. The discontinuance of the functioning of the latest Raiky sites (Monastyrok and Kaniv settlements) can be attributed as the consequences of the first stages of consolidation of the Rus people in the Middle Dnieper dating to the late 9th — the turn of the 9th—10th centuries.


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