channel processes
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Author(s):  
Alexsandr Poliarus ◽  
Andrey Lebedynskyi ◽  
Evgen Сhepusenko

There is a significant increase in the amount of measuring information at complex and large technical objects, such as bridges. Decision making about these objects states under non-stationary input influences is a difficult task. The article proposes to make the transition from single-channel information processing to multi-channel one. Each channel processes one of the Hilbert-Huang modes, into which each realization of the nonstationary signal decomposes. It is shown that the first three modes of decomposition are often enough, which in most cases create a stationary process. If a mode is non-stationary, it is possible to decompose it into these modes. The final decision according to statistical criteria is made not on realizations as it is traditionally carried out, but on Hilbert-Huang modes.


2021 ◽  
Vol 2131 (3) ◽  
pp. 032076
Author(s):  
M Matugin ◽  
D Miltsin ◽  
M Reshetnikov ◽  
A Mazgaleva

Abstract The article discusses the ways of improving the method of combined plans for a water body channel reformations analysis on the example of a section of the Oka River. The main disadvantages of the existing classical approach to the analysis of channel processes through the channel surveys separate isobaths’combination are highlighted. A new approach to combining digital models of the river bed relief obtained from the hydrographic surveys results is proposed. Two directions of surface comparison are shown for the subsequent analysis of channel processes. For a qualitative assessment of channel changes, it is proposed to construct a new surface of vertical deformations and visualize it in color gradation or using lines of equal vertical deformations. For a quantitative assessment of channel processes, the use of a cartogram of vertical channel deformations is considered, and the numerical parameters for assessing the stability of the river channel are introduced. For the considered section of the Oka river channel, the main indicators of channel processes were obtained and analyzed using the proposed updated method. Separately, the calculation of the most optimal grid size was performed when constructing a cartogram of vertical channel deformations.


2021 ◽  
Vol 29 (4) ◽  
pp. 380-386
Author(s):  
A. A. Chemagin

The study of the spatiotemporal distribution of fish is an important and poorly studied aspect of the ecology of aquatic organisms. The research work was performed using the modern hydroacoustic method and geographic information systems. A section in the lower reaches of the Irtysh, a large transboundary Siberian river (in Western Siberia, Russian Federation), was studied. It has a strong development of meandering. The merging (i.e., reshaping of closely spaced meanders and erosion-accumulating channel processes) results in development of wintering riverbed depression, which is a critical “temporal bottleneck” during the winter period of the fish life cycle. The average density of fish in the study area in summer and autumn was 8,031 and 9,194 individuals per ha, respectively. Analysis of the distribution of fish showed that the distribution in the horizontal aspect had a more aggregated character in the autumn. In the vertical aspect, it had a more surface (pelagic) character. The ichthyofauna in the water area of the riverbed depression is mainly represented by cyprinids. The loop-shaped evolution of the channel formed a section of the river with multidirectional, circulating, and counter-current flows. It also created zones with depths exceeding 20 m and aggregations of fish. These features characterize the studied water area as a wintering riverbed depression of the fish of the Lower Irtysh. This section of the river should be included in the list of protected wintering biotopes of fish in the West Siberian fishery basin, which will ensure the conservation of fish at the critical stage of the life cycle.


2021 ◽  
Vol 885 (1) ◽  
pp. 012053
Author(s):  
E A Batotsyrenov

Abstract The article provides information on the manuscript atlas of the Selenga and Orkhon rivers within the Mongolian People’s Republic (MPR), compiled on the basis of data from 1924-1925. It was developed for the Selenga Technical Section of the Ministry of the River Fleet to guide navigation along the rivers of Mongolia. The shooting was carried out on a steam boat “Shilka”. The atlas is of interest for the dynamics of river channel processes in northern Mongolia. The materials provide information on where and how to carry out technical work to improve navigation. In addition to information on navigation, it provides economic and geographical information on the north of Mongolia in the 1920s.


2021 ◽  
Vol 30 (2) ◽  
pp. 215-230
Author(s):  
Khrystyna V. Burshtynska ◽  
Svitlana S. Kokhan ◽  
Andrii V. Babushka ◽  
Ihor M. Bubniak ◽  
Volodymyr M. Shevchuk

The proposed research sets the task of conducting monitoring aimed at determining the horizontal displacements of the channel of the Stryi River the largest right-bank tributary of the Dniester River. For this purpose, the river was zoned according to morphometric and hydrological characteristics. Three parts were identified, namely highland, piedmont and lowland ones, which radically vary in the nature of the flow and the amount of the displacement. The main research purpose consists in analyzing the impact of anthropogenic factors on the hydrological regime of the Stryi River, as well as studying the effect of the Ukrainian Carpathian Foredeep (UCF) and the Stryi Deep on the mode of horizontal displacements. The research object is processes occurring within the Stryi River channel. Considering main natural factors affecting the channel’s horizontal displacements, special attention is paid to the geological and sedimentological structures located in the region where the Stryi River and its tributaries flow; among the anthropogenic factors, deforestation and the extraction of building materials from the river channel are highlighted. Topographic, geological, soil maps and satellite images of various periods uploaded into ArcGIS software allowed us to monitor displacements observed for as long as 140 years ago. To monitoring the Stryi River channel displacements, such materials as topographic maps scaled 1: 75000 (Austrian period – 1874), 1: 100000 (Polish period – 1933, Soviet period – 1990); satellite images of Sentinel-2 (2019 and 2020 (after the flood)); a map of Quaternary sediments and a soil map scaled 1: 200000 were used. The Stryi River flows between two structures, i.e. the Skybovi Carpathians and the UCF. The right-bank tributaries (Bystrytsia, Limnitsia, Stryi, etc.), which begin in the Carpathians, cross the outer and inner boundaries of the UCF and are characterized by the stable river channel in its mountainous part, multi-braided in its piedmont part, as well as perennial and significant meandering within the Pre-Carpathian region. Lithological deposits have a significant impact at the mouth of the Stryi River. According to the research study results, displacements of up to 1,350m are measured in this area. The research includes an analysis of the influence of geological and sedimentological structures on the Stryi River displacement and the nature of its flow. It has been established that deforestation in the river basin, as well as unauthorized extraction of gravel materials, creates a significant environmental problem in this region. The results of monitoring of the channel deformation processes should be taken into account when solving problems related to river channel processes, namely the construction of hydraulic structures, the design of power transmission networks crossing rivers, the development of gas pipelines, the identification of hazardous flooding zones, the determination of consequences of destruction after floods, the establishment of boundaries of water protection zones, the management of recreational activities, monitoring of border lands and the establishment of an interstate border along rivers.


2021 ◽  
Vol 2021 (1) ◽  
pp. 72-78
Author(s):  
Volodymyr Snitynskyi ◽  
◽  
Petro Khirivskyi ◽  
Ihor Hnativ ◽  
Roman Hnativ ◽  
...  

Prykarpattia is one of the areas in Europe most prone to floods. Recent environmental research predicts a trend towards an increase in these dangerous phenomena in the Carpathian region of Ukraine. The analysis of the losses caused by floods in Lviv region shows that the allocation of funds for the elimination of the consequences of floods is growing every year. It is necessary to introduce comprehensive regulation of riverbeds, taking into account the development of channel processes and forecasting possible changes under the influence of hydraulic structures. The purpose of the study is to analyze the factors influencing landslides and erosion in the foothills of the Ukrainian Carpathians and the choice of optimal flood protection of populated areas.


Author(s):  
Nikhilesh Singh ◽  
Medha Jha ◽  
Sanjay Tignath ◽  
Bhola Nath Singh ◽  
Arghya Chattopadhyay

The present paper attempts to study the causative physicochemical properties of the soils, which effectively portray its dispersive and deteriorating conditions, which have led to the formation of badlands in the Mandakini River watershed Chitrakoot area, India. Following investigations were made on the soil samples collected from the field: i) grain size distribution ii) various physicochemical properties and nutrient content of the soil. The clay minerals were detected and identified with the X-ray diffraction (XRD), Fourier transform infrared (FTIR), and High-Resolution Scanning Electron Microscopy (HRSEM). The spatial maps of all these parameters were prepared in a GIS environment, and overlay analysis was performed. The results show that the soil has a silt loam texture with high bulk density. The low values of plastic limit, liquid limit, and plasticity index show the non-cohesive nature of the soils. Higher bulk density has decreased the porosity as well as permeability in the soils. This impact on porosity and permeability has reduced the favourable conditions for vegetation, and the soils contain low organic matter. Apart from the bulk density, the presence of calcrete and illitic clay mineral (low in content) has also reduced the permeability of the soils, further increasing runoff. The overlay analysis based on the liquid limit, plasticity index, bulk density, and drainage frequency shows that the area is thoroughly affected by badland processes. Three zones were categorized as severe, very severe, and extremely severe depending upon their conditions gully channel processes.


2021 ◽  
Vol 4 (1) ◽  
pp. 126-136
Author(s):  
Alexander T. Zinoviev ◽  
Alexander V. Dyachenko ◽  
Konstantin B. Koshelev ◽  
Konstantin V. Marusin

Computer simulation of channel morphodynamic for the section of a large river in real unsteady hydrological conditions is conducted. The Ob river channel section at Barnaul city is investigated. At the site considered the channel processes cause serious hazard to some important structures such as the municipal water intake and the power line. The time of modeling covers the period from the flood peak to the low water stage. The simulation is implemented by means of Delft3D program suite. The sediment transport is calculated by two types of Van Rijn’s formula (1984 and 1993). The simulation results are verified by the field data collected at the study site over the same time period. These results show poor agreement with the field data. The river bed erosion spatial pattern modeled differs from the real one significantly. Probably a reason of this discrepancy is that the formula used can’t estimate the sediment transport value correctly.


2021 ◽  
Vol 58 (1) ◽  
pp. 4164-4172
Author(s):  
Sri Setiawati, Silvia Ekasari, Marjan Miharja

Supply chain which is a system that involves the production, delivery, storage, distribution and sales processes of products to meet demand. Distribution channels which are important in the supply chain, which are concerned with moving goods from one place to another effectively and efficiently. The purpose of this study was to identify the distribution channels of the supply chain for rice, chilies, shallots, beef and chicken in Depok City. The analytical method used is qualitative. Data collection techniques by means of observation, interviews and documentation. The results showed the distribution channel processes of rice, chilies, shallots, beef and chicken meat that occurred in Depok Cityhave to go through several hands including farmers, producers, distributors (traders) until it reaches consumers. Farmers in Depok City should cut the existing distribution channels by selling their crops directly to traders without going through collectors.


Author(s):  
Nazar Rybak

The morphodynamic classification of the Sukil river channel made it possible to determine the hydromorphological processes and to study the factors that determine them. The channel was classified according to the method of R.S. Chalov. Three main classification criteria were taken into account: the geomorphological type of conditions for the formation of the channel; the type of channel processes; the mophrodynamic type of channel. According to the geomorphological type of channel-forming conditions, the channel is divided into the incised channel – located mainly in mountainous and semi-mountainous parts with a characteristic the narrow valley, laid in sandstones, siltstones, and argillites; confined channel – located in intermountain basins, with one bank of channel composed of bedrock, and the other – of Quaternary sediments; wide-floodplain channel – mainly located in the lower part of the channel on the Stryi-Zhydachiv basin, laid in the Quaternary deposits of loams and sands. According to the type of channel processes, the channels with developed alluvial forms and without developed alluvial forms are dominant. Together they make up 2/3 of the channel. Other types of channels are wide-floodplain – characterized by slow flow and stable development of the meandering process, and rapid-waterfall – located in the upper reaches of the channel. The latter is characterized by a stormy current and the presence of numerous rapids made of boulders and wood. There are 3 main morphodynamic types of the channel – meandering, branched, and straightforward, and 6 their subtypes. Meandering, incised channels are characterized by structural meanders, their shores are composed of hard rocks, mostly sandstones. The meandering confined channels are defined by the root bank in the apical part and the upper wing along the root bank, which leads to the formation of segmental and blockage convolutions. Meandering, broad-flooded channels are characterized by longitudinal displacement of meanders, their convolutions are segmented, rarely loop-shaped. The coefficient of meandering gradually increases from the mountainous part of the channel to the plain one (1.10–1.35). Branched type is represented by a single complex and floodplain-channel subtypes. The size of the islands that divide the channel into arms is from a few meters to 350–400 m. The straightforward type of channel is widespread and is 1/3 of the total length of the river. Key words: channel type; straightforward; branched; meandering; incised; confined; floodplain.


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