Fundamental and Applied Hydrophysics最新文献

{"title":"Akhi A.V. Efficiency of Identification of Complex Noise-Like Signal Classes by Dolphins (Tursiops truncatus) under Simultaneous Presentation Spatial Uncertainty","authors":"A. Akhi","doi":"10.59887/fpg/vxe3-6531-nkup","DOIUrl":"https://doi.org/10.59887/fpg/vxe3-6531-nkup","url":null,"abstract":"The possibility of dolphin’s auditory system to solve the complex problem of identifying and classifying noise-like signals according to certain invariant features is considered under conditions of spatial uncertainty of their simultaneous presentation. There was studied the ability of bottlenose dolphins, which were trained to recognize and classify such signals, to select a certain class of signals from several that sound simultaneously. The dolphin had to recognize a positive class signal with a pair of simultaneously sounding signals: positive-negative (alternative choice) and with simultaneously sounding three signals: positive-negative-negative (multiple choice). It’s shown that the dolphin effectively solves the problem with a simple alternative choice of two signal sources, at the limit of reliability when choosing from three sources and unreliable when choosing from more sources.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116920433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Topographic Factor and Limit Transitions in the Equations for Subinertial Waves","authors":"V. Gnevyshev, V. Travkin, T. Belonenko","doi":"10.59887/fpg/92rg-6t7h-m4a2","DOIUrl":"https://doi.org/10.59887/fpg/92rg-6t7h-m4a2","url":null,"abstract":"In this paper, sub-inertial waves propagating on the Kuril shelf and the oceanic trench are considered. Against the background of a historical review of the beginning of the study of topographic waves and the appearance of relevant terms, a description of the features of wave propagation and the derivation of the main dispersion equations are given. We show that all variants of the topographic solutions presented in the article are basically based on the same dispersion relation: this is the dispersion relation for Rossby topographic waves. Two separate classes of localized solutions have been constructed: one is for the shelf, and the second, in fact, is also for the shelf, but which is commonly called trench waves. We demonstrate that the transverse wave number for trench waves is not independent, as for shelf waves, but is a function of the longitudinal wave number. In other words, Rossby topographic waves are two–dimensional waves, while shelf waves are quasi-one-dimensional solutions. The analytical novelty of the work consists of the fact that we can make crosslinking of trench and shelf waves. This fact was not presented in previous articles on this topic.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"105 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121216145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the Influence of Spatial Fluctuations of the Water Inherent Optical Properties on the Energy of a Lidar Echo Signal Coming from a Water","authors":"Ульяна Александровна Ульянова, Нижний Новгород, И. Лобачевского, пр. Гагарина","doi":"10.59887/fpg/1gan-g7mu-dk9p","DOIUrl":"https://doi.org/10.59887/fpg/1gan-g7mu-dk9p","url":null,"abstract":"Theoretical models of the statistical characteristics of the lidar echo signal have been developed to interpret the results of optical sounding of heavily eutrophicated water bodies. Formulas are obtained for calculating the statistically average value and coefficient of variation of the energy of the elastic backscattering signal coming from the near-surface layer of water with randomly inhomogeneous absorption and scattering coefficients. Examples of the dependence of the indicated signal characteristics on the coefficients of variation of the optical characteristics of water are given. It has been established that fluctuations in the absorption coefficient lead to an increase in the average energy of the received signal, and fluctuations in the scattering coefficient to its slight decrease. A significant decrease in the average echo signal energy can be observed with cross-correlated fluctuations in the absorption and scattering coefficients, i. e. in the case when the attenuation coefficient fluctuates at a constant single scattering albedo. Considerations are made on how algorithms for estimating the average values of the optical characteristics of water and the parameters of their inhomogeneities from the average value and the coefficient of variation of the echo signal energy can be constructed.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"151 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127285648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sensitivity of Seawater Temperature and Salinity to their Restoring Times, Appending in the Boundary Conditions for these Variables at the Free Surface of the Laptev Sea in the No-Ice Period","authors":"B. Kagan, E. Sofina","doi":"10.59887/fpg/m5h2-uu55-3va9","DOIUrl":"https://doi.org/10.59887/fpg/m5h2-uu55-3va9","url":null,"abstract":"In order to study sensitivity of seawater temperature and salinity in the no-ice Laptev Sea to their restoring times, appending in the boundary conditions for these variables at the free surface, the 3D finite-element hydrostatic model QUODDY-4 and the indirect means of describing internal tidal waves have been applied. The latter is based on the use of the corrected eddy diffusivity representing the sum of the same uncorrected diffusivity and the diapycnal diffusivity. The first of them characterizes the influence of non-tidal factors, computed using 2.5-level eddy closure scheme, the second, determined by the ratio of internal tidal waves induced baroclinic tidal energy dissipation to the buoyancy frequency in square, the influence of purely tidal factor. The estimate of this dissipation obtained from a solution of auxiliary problem on the internal tidal waves dynamics and energetics is attached. Seawater temperature and salinity in the subsurface and near-bottom layers of the Sea and also their vertical distributions along the 120E meridional transection obtained for the strong, moderate, and mixed restoring times are discussed. As a result, it is clarified that seawater temperature and salinity are weakly sensitive to changes in the restoring time. The saying follows from a comparison of model averaged (over a chosen period and by the Sea area) values of seawater temperature and salinity, and from their local vertical profiles, computed with regard to accepted estimates of the restoring time.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"457 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132761192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The catastrophic flood of the Neva, September 10 (21), 1777. So, in what feet it was measured…","authors":"T. I. Malova, A. Rodionov","doi":"10.59887/fpg/ex7e-unv4-xd1r","DOIUrl":"https://doi.org/10.59887/fpg/ex7e-unv4-xd1r","url":null,"abstract":"The height of one of the most outstanding floods of the Neva on September 10 (21), 1777 is practically not captured on the walls of buildings and structures in St. Petersburg. In this context, the leveling catalog, which reflects more than 700 height marks of this flood, and plans with the location of these marks within St. Petersburg, seems to be absolutely unique and very relevant. The author of the catalog is Friedrich Wilhelm Bauer, quartermaster general, surveyor, cartographer. Work on leveling the flooded urban areas was carried out at the behest of Catherine II. In the leveling catalog of F.V. Bauer notes that the maximum height of the water in the flood of 1777 reached 10 feet 3 inches and that it was measured from the ordinary of the Admiralty footstock. To measure excess F.V. Bauer used the French linear measure, which made it possible to recalculate the maximum flood height to a value of 333 cm.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"5 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122535452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Solution Options for Problems of Navigation on a Limited Section of the Volga River from Gorodetsky Hydroelectric Complex to Nizhny Novgorod, Including Taking Into Account the Assessment of the Impact on the Sanitary-Epidemiological and Environmental Situation in the Region","authors":"A. Rodionov, V. A. Rumyantzev, M. P. Fyodorov, A. Zinoviev, V. A. Krivosheĭ, O. Y. Medvedeva, Y. Troitskaya, S. P. Dyomin, T. I. Malova, A. Chusov, O. D. Shishkina, A. V. Moiseev, S. B. Kamenskiy, I. M. Krayev, K. Marusin","doi":"10.59887/fpg/abfh-m2n7-9mn6","DOIUrl":"https://doi.org/10.59887/fpg/abfh-m2n7-9mn6","url":null,"abstract":"The paper proposes a variant of choosing the optimal solution to the large-scale scientific, technical and ecological-economic problem of the European part of the Russian Federation based on the integrated use of results of numerical modeling of hydrodynamic processes, expert environmental assessments and rating economic comparison.The object of scientific research is the section of the Volga River from the Gorodetsky hydroelectric complex to Nizhny Novgorod (from 852.5 to 899 km along the ship’s course). The purpose of the work is to prepare proposals for the choice of an option for improving navigation conditions on the Volga River section under consideration in the lower reaches of the Gorodetsky locks under various flow regimes through the Gorodetsky hydroelectric complex, taking into account the priorities of environmental protection, protection of water bodies and use of water resources established by legislation. As a result of the work, a variant of the project proposed for implementation on the territory of the Nizhny Novgorod region for the rational solution of navigation problems on the Volga River, taking into account the assessment of the impact on the sanitary-epidemiological and environmental situation in the region, flooding and flooding zones. The project includes the construction of a third parallel lock in the area of Gorodetsky locks No. 15–16 and the creation of a navigable slot with a guaranteed fairway depth of 4.0 m.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131518686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Laboratory Study of Surfactant Film Compression and Boundary Transformation under the Action of Surface Waves","authors":"D. V. Vostryakova, I. Kapustin, T. Lazareva, O. Danilicheva, S. Ermakov","doi":"10.59887/fpg/xk62-mm5t-fhph","DOIUrl":"https://doi.org/10.59887/fpg/xk62-mm5t-fhph","url":null,"abstract":"In this paper we present the results of a laboratory experiment simulating the mechanisms of a surfactant film localization under the action of periodic surface waves. It is shown that the film compressed by a surface wave, can be conditionally divided into three sections — the dense film region as the most distant from the wave source, the area of a diluted film and the region of relatively clean water. The paper is focused on the processes occurring in the diluted film region characterized by the transition from clean water to the dense film, where horizontal circulation currents are registered. The character of currents is varying depending on the wave amplitude so that the divergent circulation cells occur at small and large wave amplitudes, but at medium amplitudes the roller currents forming a convergence zone on the basin axis are observed. The experimentally obtained stationary distribution of surfactant concentration is compared with the previously developed model of film compression due to surface tension induced by waves. The comparison shows good agreement between the theory and the experimental results at small and large wave amplitudes. Their discrepancy at medium wave amplitudes in the diluted film region is presumably related to the presence of convergent cells which are not considered in the model.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"125 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115752349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling of Hydrodynamic and Lithodynamic Coastal Processes in the Harbour Area","authors":"A. Anshakov","doi":"10.59887/fpg/xhaz-46hz-kk62","DOIUrl":"https://doi.org/10.59887/fpg/xhaz-46hz-kk62","url":null,"abstract":"One of the problems in the design of ports is the assessment of coastal sediment movements near structures. The article presents materials for assessing the impact of port facilities on the processes of coastal erosion/accumulations in the area of Gelendzhik Bay (Black Sea). All the main processes of interaction of waves, currents and sediment movement occur in the coastal zone, therefore, the study presents the possibilities of complex application of hydrodynamic and lithodynamic models. In this work, the wind wave models Wave Watch III and SWAN were used. As the initial data, the data of the NCEP/NCAR reanalysis of wind fields in the period from 1989 to 2012 were used. To simulate currents, sediment transport and lithodynamic processes, a model of two-dimensional COASTOX–CUR currents generated by waves and wind, COASTOX-SED sediment transport together with the COASTOX–MORPHO bottom reshaping model was used. In the simulation scenario, a sequence of the 5 strongest storms from the period under consideration was considered. Analysis of washout zones/accumulations have shown that areas of intensive bottom reshaping are associated with the most intense currents. It is shown that the construction of the port facilities will not have a significant impact on the lithodynamic processes in the Gelendjik bay.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"104 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127144011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Noise Signal Modulation at the Ship Rolling and Pitching due to Fluctuating Interference of Beams","authors":"A. D. Konson, A. A. Volkova","doi":"10.59887/fpg/xgkz-naer-b78u","DOIUrl":"https://doi.org/10.59887/fpg/xgkz-naer-b78u","url":null,"abstract":"Amplitude modulation of a noise signal of the surface ship is formed both directly at noise emission, when the line of the shaft and the propeller is rotating, and in addition due to the ship rolling and pitching caused by the rough sea. At the same time additional low-frequency (no more than 0,2 Hz) amplitude modulation of the noise emission can be observed as a process of temporary variations of the received signal power. In this regard, it is interesting to find relation of the amplitude-phase modulation spectrum of the ship broadband signal at its rolling and pitching with the spectrum of rolling and pitching process. As a mechanism of formation of the noise signal modulation at the ship rolling and pitching the fluctuating interference of the beams, propagating from vertically dipping underwater point source near the water surface, is considered. The analytical ratios connecting the amplitude-phase modulation spectrum of the ship broadband signal at its rolling and pitching with the spectrum of rolling and pitching process are received.As a result, the parameter describing cumulative conditions by which it is possible to determine spectral properties of modulation is determined. The type of the power variation spectrum can be substantially different depending on values of parameter K = 2kσH sinα 1 where k — the wave number, σH-root mean square value of the vertical component (source shift) due to rolling and pitching, α — the beam grazing angle at the surface. At value 2kσHsinα< 1 results of observation of the signal modulation process can be identified with process of the ship rolling and pitching. At value 2kσHsinα> 1 the signal modulation spectrum will not correspond to the spectrum of rolling and pitching process. With the increase of parameter K value the modulation spectrum extends, goes beyond the spectrum of rolling and pitching process. Significantly lower and high harmonics emerge. Results of computer modeling and natural experiments confirmed dependence of the type of the modulation spectrum on parameter K. Thus, presence of the additional mechanism of noise signal modulation formation at the ship rolling and pitching, caused by the phenomenon of fluctuating interference of the beams propagating from vertically dipping underwater point source near the water surface is found.","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130432062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review of the monograph by G.S. Malyshkin and V.S. Melkanovich “Classical and fast projection adaptive algorithms in hydroacoustics”","authors":"A. Mashoshin","doi":"10.59887/fpg/12ba-kakg-gxd4","DOIUrl":"https://doi.org/10.59887/fpg/12ba-kakg-gxd4","url":null,"abstract":"<jats:p>.</jats:p>","PeriodicalId":218146,"journal":{"name":"Fundamental and Applied Hydrophysics","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114175381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}