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1.
Comparative analysis of approaches and methods of biological assessment of water quality is presented. A method of ecotoxicological diagnostic of aquatic ecosystem health and water quality evaluation based on the physiological state of fish are substantiated. Characteristics of the main symptoms of diseases in fish inhabiting freshwater bodies and pathologic disturbances in their organs and tissues, caused by water bodies contamination with toxic substances, are presented. The method of ecotoxicological assessment of water quality is shown to be both highly informative and easy-to-use in practical monitoring.Translated from Vodnye Resursy, Vol. 32, No. 2, 2005, pp. 184–195.Original Russian Text Copyright © 2005 by Moiseenko.  相似文献   

2.
Factors responsible for the formation of water salinity in the Yumaguzinskoe Reservoir, which is under construction in the upper reaches of the Belaya River, are analyzed. Based on the prediction experience and a sufficient amount of initial data on water quality of the Belaya River, the universally accepted algorithm of prediction for years of different water supply levels using the calculation method of running-out has been modified. As revealed, the minimum water salinity at the reservoir spillway is observed in May–August, the maximum water salinity being in January–March. The regularities of a general nature have been found.Translated from Vodnye Resursy, Vol. 32, No. 2, 2005, pp. 214–222.Original Russian Text Copyright © 2005 by Popov, Oboldina.  相似文献   

3.
Results of hydrochemical and microbiological studies of five largest water bodies belonging to the Gusino-Ubukunskaya group are presented. Present-day environmental state of the ecosystem subject to anthropogenic load is described. The possibility of using water quality parameters of the investigated lakes as indicators of the degree of contamination of waters flowing into the Baikal Lake is shown.Translated from Vodnye Resursy, Vol. 32, No. 1, 2005, pp. 79–84.Original Russian Text Copyright © 2005 by Khakhinov, Namsaraev, Ulzetueva, Barkhutova, Abidueva, Banzaraktsaeva.  相似文献   

4.
The role of wave processes and turbulence in impurity transport, flow interaction with bottom sediments, and the formation and destruction of ice cover was determined on the basis of analysis of field measurement data on flow velocities and water levels in the Rybinsk Headwork tailrace in the presence and absence of water releases in summer and winter.__________Translated from Vodnye Resursy, Vol. 32, No. 3, 2005, pp. 274–281.Original Russian Text Copyright © 2005 by Debolskii, Dolgopolova, Eshchenko, Kotlyakov, Mordasov, Konov, Koreneva.  相似文献   

5.
Results of a special experiment conducted in the summer of 2002 in the Central pool of the Mozhaisk Reservoir are discussed. The experiment was aimed at studying short-period and small-scale variations in water temperature, electric conductivity, transparency, dissolved oxygen content, total and mineral phosphorus, phyto-, microzoo- and zooplankton. Statistical characteristics of the above-mentioned environmental parameters are presented.__________Translated from Vodnye Resursy, Vol. 32, No. 3, 2005, pp. 352–360.Original Russian Text Copyright © 2005 by Datsenko, Edelshtein, Goncharov, Puklakov, Chernega.  相似文献   

6.
Sakhalinskii Shelf information and analytical GIS based on observational data is used to simulate hydrological parameter values at standard horizons of stationary stations in the La Perouse Strait. The spatial and temporal distribution pattern for oceanographic parameters has been obtained. Water masses and water structures have been identified using classic T, S-analysis. Volumetric T, S-analysis of waters is used to evaluate the volumes, heat content, and salinity of the water masses chosen. For the first time, information for the winter season, which is the least investigated season and for which no generalizations whatsoever have been made until the present, has been obtained.Translated from Vodnye Resursy, Vol. 32, No. 1, 2005, pp. 18–27.Original Russian Text Copyright © 2005 by Pishchalnik, Arkhipkin, Leonov.  相似文献   

7.
Riassunto Data una variabile casuale X che segue la legge normale di probabilitl con valor medio a ed error medio y 1'A. considera un'altra variabile casuale che prende il valore intero r quando r–1/2
Summary Given a random variable X following the normal probability law, with expectation a and standard error p, the author considers another random variable , that takes the entire value r when r–1/2  相似文献   

8.
Methods used to analyze one type of nonstationary stochastic processes—the periodically correlated process—are considered. Two methods of one-step-forward prediction of periodically correlated time series are examined. One-step-forward predictions made in accordance with an autoregression model and a model of an artificial neural network with one latent neuron layer and with an adaptation mechanism of network parameters in a moving time window were compared in terms of efficiency. The comparison showed that, in the case of prediction for one time step for time series of mean monthly water discharge, the simpler autoregression model is more efficient.Translated from Vodnye Resursy, Vol. 32, No. 2, 2005, pp. 133–145.Original Russian Text Copyright © 2005 by Pisarenko, Lyubushin, Bolgov, Rukavishnikova, Kanyu, Kanevskii, Saveleva, Demyanov, Zalyapin.  相似文献   

9.
Results of field observations and numerical modeling of hydrogen sulfide pollution of the Sea of Azov in 2001 are presented.Translated from Vodnye Resursy, Vol. 32, No. 2, 2005, pp. 171–183.Original Russian Text Copyright © 2005 by Debolskaya, Yakushev, Sukhinov.  相似文献   

10.
Zusammenfassung 1) Es werden Multipollösungen der skalaren Wellengleichung 2 f/t 2 – c2 div gradf=0 betrachtet. Einerseits kann man solche Lösungen direkt durch Kugelfunktionenn-ter Ordnung ausdrücken, anderseits aus der Einpollösungf=1/p F(t–p/c) durch Differentiation nachn Richtungen erhalten. Es wird der Zusammenhang zwischen den Ergebnissen der beiden Verfahren gezeigt. — 2) Für die Energiedichte und den Energiefluss durch Kugelflächen bei kleinen elastischen Verschiebungen werden Ausdrücke in Kugelkoordinaten angegeben. — 3) Für die Wellengleichung grad div –b 2 rot rot werden rotationsfreie Multipollösungen angegeben und Ausdrücke für Energiedichte und Energiefluss hergeleitet. — 4) Das gleiche wird für divergenzfreie Multipollösungen durchgeführt. — 5) Es werden Multipole betrachtet, die weder rotationsfrei noch divergenzfrei sind. Als Spezialfälle werden Multipole mit zeitlich begrenzter und solche mit periodischer Erregung gezeigt, ferner Lösungen der Wellengleichung, die sowohl rotationsfrei wie divergenzfrei sind. — 6) Es wird gezeigt, wie man die elastischen Wellen, die im Sinne vonStokes von einem Herdgebiet endlicher Ausdehnung ausgehen, näherungsweise durch elastische Multipole darstellen kann. — 7) Es wird angedeutet, wie man durch Messung von Komponenten von oder u.s.w. in Punkten im Innern des Mediums die Erregung und Energie von elastischen Multipolen bestimmen kann. Ferner wird auf den Fall hingewiesen, wo ein rotationsfreier Einpol sich im Innern eines Halbraumes befindet und die Messungen an seiner Oberfläche ausgeführt werden.
Summary (On foci of elastic waves in isotropic homogeneous media) — 1) Multiplets as solutions of the scalar wave equation 2 f/t 2 – c2 div gradf=0 are considered. Such solutions can be obtained either directly by aid of spherical harmonics of ordern, or by differentiating the single polef=1/p F(t–p/c) with respect ton directions. The relations between the results of those two procedures are shown. — 2) In the case of small elastic displacements , the density of energy and the flow of energy through spherical surfaces are expressed by spherical coordinates. — 3) Multiplets which satisfy the equation of motion =a 2 grad div b 2 curl curl and the equation curl = 0 are given, and expressions for the density and flow of energy are found. — 4) The same is done with multiplets satisfying the equation of motion and the equation div = 0. — 5) General multiplets which satisfy the equation of motion are treated. As special cases, multiplets with excitation of finite length and multiplets with periodic excitation are considered, furthermore solutions of the equation of motion and of the equations curl = 0 and div = 0 are given. — 6) It is shown how elastic waves whose origin is a region of finite extension in the sense given byStokes, can be approximated by elastic multiplets. — 7) Some indications are given on the problem of how to find the functions of excitation and the energy of an elastic multiplet by measuring components of or etc., at points in the interior of the medium. The same problem is considered in the case of the single elastic pole. = grad 1/p F (t–p/a), if the measurements are made at the surface of an elastic half space.
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11.
Recreational fishing is a popular activity in many urbanized watersheds. When river water is incidentally ingested during fishing sessions, substantial waterborne fecal contamination can cause adverse health effects. This study aims to spatially map health risks for recreational fishers caused by waterborne Escherichia coli (E. coli) in the highly urbanized Tamsui River watershed. First, indicator kriging was used to probabilistically estimate the distributions of waterborne E. coli and determine the conditional cumulative distribution function (CCDF). Subsequently, to propagate the parameter variability, Monte Carlo simulation was adopted to characterize the ingestion rate and exposure duration for recreational fishers and E. coli realizations were generated using random fields on the basis of the estimated CCDF. Finally, after the three parameters were combined, the approximate beta-Poisson dose–response function was employed to quantitatively determine potential risks to recreational fishers in the Tamsui River and its tributaries. The analysis results revealed that the risks of recreational fishing exceed an acceptable level of 8 infections per 1000 fishers per day at several urban river courses. Therefore, recreational fishing activities in urban riverbanks pose a substantial health threat. Recreational fishing in urban riverbanks should be limited before the construction of complete sanitary sewer systems. The river mouth and certain upstream river sections are suitable for the development of recreational fishing.  相似文献   

12.
Summary If the condition R(A)=k(n), whereA is the design matrix of the type n × k and k the number of parameters to be determined, is not satisfied, or if the covariance matrixH is singular, it is possible to determine the adjusted value of the unbiased estimable function of the parameters f(), its dispersion D( (x)) and 2 as the unbiased estimate of the value of 2 by means of an arbitrary g-inversion of the matrix . The matrix , because of its remarkable properties, is called the Pandora Box matrix. The paper gives the proofs of these properties and the manner in which they can be employed in the calculus of observations.  相似文献   

13.
Piest  Jürgen 《Ocean Dynamics》1963,16(1):9-14
Zusammenfassung Als Zusammenhang zwischen der kennzeichnenden Wellenperiode und der durchschnittlichen Periode im Seegang wird die Formel angesetzt. Mit Hilfe empirischer Unterlagen wird nachgewiesen, daßc eine Funktion des von D. E. Cartwright und M. S. Longuet-Higgins [1956] eingeführten Spektralparameters ist. Es wird eine vorläufige quantitative Beziehung zwischenc und abgeleitet.
Empirical investigations of the relation between the mean and the significant wave period in the sea
Summary It is supposed that the formula represents the relation between the significant wave period and the mean period in the sea. With the aid of empirical data it is demonstrated thatc is a function of the spectral parameter introduced by D. E. Cartwright and M. S. Longuet-Higgins [1956]. A preliminary quantitative relation betweenc and is derived.

Etudes empiriques de la relation entre la période moyenne et la période significative des vagues dans la houle
Résumé On suppose que la formule représente la relation entre la période significative des vagues et la période moyenne dans la houle. A l'aide des données empiriques on montre quec est une fonction du paramètre spectral , introduit par D. E. Cartwright et M. S. Longuet-Higgins [1956]. Une relation quantitative préliminaire entrec et est dérivée.

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14.
We present a comparative study of soil CO2 flux () measured by five groups (Groups 1–5) at the IAVCEI-CCVG Eighth Workshop on Volcanic Gases on Masaya volcano, Nicaragua. Groups 1–5 measured using the accumulation chamber method at 5-m spacing within a 900 m2 grid during a morning (AM) period. These measurements were repeated by Groups 1–3 during an afternoon (PM) period. Measured ranged from 218 to 14,719 g m−2 day−1. The variability of the five measurements made at each grid point ranged from ±5 to 167%. However, the arithmetic means of fluxes measured over the entire grid and associated total CO2 emission rate estimates varied between groups by only ±22%. All three groups that made PM measurements reported an 8–19% increase in total emissions over the AM results. Based on a comparison of measurements made during AM and PM times, we argue that this change is due in large part to natural temporal variability of gas flow, rather than to measurement error. In order to estimate the mean and associated CO2 emission rate of one data set and to map the spatial distribution, we compared six geostatistical methods: arithmetic and minimum variance unbiased estimator means of uninterpolated data, and arithmetic means of data interpolated by the multiquadric radial basis function, ordinary kriging, multi-Gaussian kriging, and sequential Gaussian simulation methods. While the total CO2 emission rates estimated using the different techniques only varied by ±4.4%, the maps showed important differences. We suggest that the sequential Gaussian simulation method yields the most realistic representation of the spatial distribution of , but a variety of geostatistical methods are appropriate to estimate the total CO2 emission rate from a study area, which is a primary goal in volcano monitoring research.Editorial responsibility: H Shinohara  相似文献   

15.
Summary The mechanism of beating of Pc3 type pulsations is studied. Using the method of numerical computation of a sonagram (the method of frequency-time analysis) a set of samples of pulsations from the Budkov Observatory is treated (1968–1969) mostly at K-indices equal to 2–3. By comparing f–t diagrams with the spectra of the samples an attempt has been made at interpreting the beating as a superposition of the frequency components, contained in the pulsation signal. In most observed cases it is possible to determine two close frequencies, the difference of which is on the average =5.4 mHz. The average carrier frequency of the samples was =37.6 mHz, and the average frequency of the beating =2.7 mHz. The interval of observed values of fB amounted to 1–5 mHz. A tendency was observed for fB to increase with increasing degree of disturbance of the geomagnetic field.  相似文献   

16.
Résumé La formule de base, traduisant une propriété analytique d'une classe très générale de fonctions, est un corollaire du théorème fondamental démontré dans un mémoire précédent, d'après lequel, étant donnés une fonction continue,p(, ,t) des points (, ) d'une surface régulière fermée et du temps et le champ d'un vecteur vitesse de transfert ou d'advection tangent à et ayant des lignes de flux fermées et régulières, il existe un opérateur spatial, linéaire, non singulierA tel que la fonctionA(p+Const.) soit purement advective par rapport a (sans creusement ni comblement). Ce théorème peut être exprimé par l'équation , où est un opérateur spatial, linéaire et non singulier, fonction deA.La détermination de peut être faite, soit en comparant deux formes différentes de la solution générale de l'équation en , soit en utilisant un raisonnement a priori très simple. On arrive ainsi au résultat pour un certain scalaireu(, ).Dans le cas oùp(, ,t) est la perturbation de la pression sur la surface du géoïde l'équation résulte aussi, comme nous l'avons montré dans le mémoire précédent, de notre théorie hydrodynamique des perturbations. On montre ici que la même équation peut encore être déduite de l'équation de continuité associée à la condition d'équilibre quasi statique selon la verticale.Comme applications de la formule de base (solution générale de l'équation enM), on étudie les problèmes suivants: 1o creusement et comblement en général; 2o creusement et comblement des centres et des cols; 3o mouvement des centres et des cols; 4o instabilité d'un champ moyen; 5o propriétés spatiales des champsp(, ,t) et des vecteurs d'advection analytiques.Après une discussion des erreurs de la prévision d'un champp(, ,t) par la formule de base, du fait des erreurs des observations et du fonctionnement du calculateur, on examine quelques particularités du transfert ou advection d'un champf 0(, ) par le vecteur . Enfin, le dernier chapitre du mémoire donne des éclaircissements complémentaires sur la structure du calculateur électronique «Temp» (qui effectue automatiquement les opérations mathématiques de la formule de base) et expose l'état actuel de sa construction.
Summary The basic formula, expressing an analytical property of a very general class of functions, is a corollary of the fundamental theorem, proved in a previous paper, according to which, given a functionp(, ,t) of the points (, ) of a closed regular surface and of the time, and a transfer or advection velocity vector tangent to and having regular closed streamlines, there is a spatial, linear, non singular operatorA such thatA(p+const.) is a purely advective function in respect to (no deepening). This theorem can be expressed by the equation where is a spatial, linear, non singular operator depending onA.The determination of can be attained, either by the comparison of two different forms of the general solution of the -equation, or by a simple a priori reasonning. The conclusion is thus reached that for a certain scalaru(, ).Whenp(, ,t) is the pressure perturbation at sea level, it was shown, in the preceding paper, that the equation can also be derived from our hydrodynamical perturbation theory. We now show that for this particular case, the same equation is also a consequence of the equation of continuity together with the condition of quasi statical vertical equilibrium.The following problems are then analysed by means of the basic formula: 1o deepening and filling in general; 2o deepening and filling of the centres and cols; 3o motion of the centres and cols; 4o instability of a mean field; 5o spatial properties of the analytical fields and advection vectors .The errors in the forecast of a field,p(, ,t) by means of the basic formula, due to the observational and computational errors, are discussed, and some peculiarities of the transfer or advection of a fieldf 0(, ) by are examined. Finally, complementary points are disclosed on the structure of the electronic computer «Temp» which performs automatically the mathematical operations of the basic formula, and a brief report is given of the present state of its construction.
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17.
Summary The time development of three large sequences, Friuli 1976, Thessaloniki 1978 and Monte Negro-Albania 1979, was investigated by analysing the characteristics of the time distribution of magnitudes of the events, M(t), of average magnitudes, (t), and of the number of events, n(t), as well as the strain release curves and the magnitude-frequency relations, N(M). The existence of time gaps and of an anomalous decay of the numbers of shocks before major events, as well as the oscillation of ( const b–1) may be considered as precursory phenomena. The clustering of events has been tested by the Poisson and negative binomial laws.Communication presented at the XVIIth General Assembly of the European Seismological Commission in Budapest, 21–29 August, 1980 under the title Properties of Seismic Regime and Recent Earthquake Sequences in Europe.  相似文献   

18.
Summary The paper describes the seismic activity of the Jílovice fault and the last earthquake of Aug. 10, 1987.
Резюме Оnuсывaеmся сеŭсмuческaя aкmuвносmь рaзломa йuловuце в северовосmочноŭ Чехuu u землеmрясенuе с 10-о о aв усma 1987 , очa коmоро о был связaн с ?rt;aнным разломом.
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19.
Summary We find no effect of the interplanetary magnetic field(IMF) sector boundary crossing in ozone at altitudes ranging from the middle stratosphere(10 hPa) to the lower mesosphere(0.4 hPa) at middle latitudes(40°–60° N), based on winter data over the period of December 1979–December 1982.
Резюме Мы не нaшлu нuкaко о эффекma nересеченuя секmорноŭ рaнuцы межnлaнеmно о мa нumно о nоля в озоне в облaсmu высоm меж?rt;у сре?rt;неŭ сmрamосфероŭ(10 Пa) u нuжнеŭ мезосфероŭ(0,4 Пa) нa сре?rt;нuх шuроmaх(40°–60° с.ш.), nрuменяя зuмнuе ?rt;aнные зa nерuо?rt; ?rt;екaбрь 1979 – ?rt;екaбрь 1982 .
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20.
The 1999 basaltic eruption of Shishaldin volcano (Alaska, USA) included both Strombolian and Subplinian activity, as well as a “pre-Subplinian” phase interpreted as the local coalescence within a long foam in the conduit. Although few visual observations were made of the eruption, a great deal of information regarding gas velocity, gas flux at the vent and plume height may be inferred by using acoustic recordings of the eruption. By relating acoustic power to gas velocity, a time series of gas velocity is calculated for the Subplinian and pre-Subplinian phases. These time series show trends in gas velocity that are interpreted as plumes or, for those signals lasting only a short time, thermals. The Subplinian phase is shown to be composed of a thermal followed by five plumes with a total expelled gas volume of .The initiation of the Subplinian activity is probably related to the arrival of a large overpressurised bubble close to the top of the magma column. A gradual increase in low-frequency (0.01–0.5 Hz) signal prior to this “trigger bubble” may be due to the rise of the bubble in the conduit. This delay corresponds to a reservoir located at ≈3.9 km below the surface, in good agreement with studies on other volcanoes.The presence of two thermal phases is also identified in the middle of the pre-Subplinian phase with a total gas release of and . Gas velocity at the vent is found to be and for the Subplinian plumes and the pre-Subplinian thermals respectively.The agreement is very good between estimates of the gas flux from modelling the plume height and those obtained from acoustic measurements, leading to a new method by which eruption physical parameters may be quantified. Furthermore, direct measurements of gas velocity can be used for better estimates of the flux released during the eruption.  相似文献   

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