Quantitative study on characteristic parameters of acoustic behavior habits in budgerigars （Melopsittacus undulafus）

Ｑｕａｎｔｉｔａｔｉｖｅｓｔｕｄｙｏｎｃｈａｒａｃｔｅｒｉｓｔｉｃｐａｒａｍｅｔｅｒｓｏｆａｃｏｕｓｔｉｃｂｅｈａｖｉｏｒｈａｂｉｔｓｉｎｂｕｄｇｅｒｉｇａｒｓ（Ｍｅｌｏｐｓｉｔｔａｃｕｓｕｎｄｕｌａｆｕｓ）Ｊｉｎ－ＣｈａｎｇＪＩＡＮＧ（蒋锦昌）；Ｈ...     

The effect of time-dependent γ-pumping on buoyant magnetic structures

ABSTRACT

In this paper, we explore for the first time the interactions of the net downward, time-dependent, γ-pumping overlying an imposed layer of magnetic fluid, in a polytropic atmosphere. Our calculations show that an equipartition of energy, between the magnetic and kinetic components, must be reached for buoyancy-driven magnetic structures to rise into the pumping region. However, structures do not rise unhindered, as in a previous investigation. We show that the evolution and other features of the emerging magnetic flux structures are significantly affected by the temporal variation of the γ-pumping. The rate of emerging structures, the strength of magnetic concentrations and the extent to how far magnetic field can travel were all found to depend on the timescale of the γ-pumping.     

The effect of spall on Lg waves

Introduction The Lg phase plays a central role in nuclear test detection, discrimination, and yield estima-tion because of its stability in propagation, but the excitation mechanisms of Lg phase are not fully understood. Regional Lg is a short-period guided wave composed mainly of a sequence of multi-ply reflected post-critical S waves trapped in the crustal wave guide. Several studies carried out recently (Gupta et al, 1992; Patton and Taylor, 1995; Gupta et al, 1997; Wallace, 1991) have …     

The effect of Razdol’naya River on the environmental state of Amur Bay (the Sea of Japan)

Seasonal variations in biogenic substances (nitrates, nitrites, ammonium, phosphates, and silicates), dissolved oxygen, dissolved organic matter, chlorophyll, humus, and suspended matter at seven stations on the Razdol’naya River are examined. Based on seasonal variations, the local sources of river water pollution by biogenic substances were identified. The annual and daily fluxes of biogenic substances through the Razdol’naya River into Amur Bay are calculated. A diffuse pollution source—agricultural fields in river valley—are shown to be the main source of biogenic substance fluxes. The vast hypoxia in the bottom water of Amur Bay, detected by the authors in 2007 and 2008, is supposed to be mostly caused by floods on the Razdol’naya R., which create favorable conditions of water blooming in Amur Bay in summer. The biomass of dead phytoplankton, experiencing microbiological decomposition and oxidation, causes hypoxia of bottom waters in the bay.     

The effect of wind on the gravity wave propagation in the Earth’s ionosphere

The effect of ionospheric wind on the gravity wave propagation is studied. These waves arise in the ionosphere due to intensification of their sources near the Earth’s surface during enhanced seismic activity. The influence of the wind on these waves is connected with the Ampere’s force that produces the ion-drag force acting on the atmosphere. This results in the occurrence of the discrete wave spectrum the maximum of which increases in proportion to the numbers of the natural scale. Furthermore, these waves are amplified during propagation from the source region in the direction perpendicular to the wind direction. These peculiarities of the gravity waves can be used for monitoring of seismic activity based on the ionosphere sounding.     

The effect of soil–structure interaction on the seismic risk to buildings

This paper studies the effect of soil–structure interaction (SSI) on the seismic risk estimates of buildings. Risk, in this context, denotes the probability distribution of seismic monetary loss due to structural and nonstructural damage. The risk analysis here uncovers the probability that SSI is beneficial, detrimental, or uninfluential on seismic losses. The analyses are conducted for a wide range of buildings with different structural systems, numbers of stories, and foundation sizes on various soil types. A probabilistic approach is employed to account for prevailing sources of uncertainty, i.e., those in ground motion and in the properties of the soil–structure system. In this approach, probabilistic models are employed to predict the response, damage, and repair cost of buildings. To properly account for the ground motion uncertainty, a suite of nearly 7000 accelerograms recorded on soil is employed. It is concluded that structures on very soft soils are extremely likely to incur smaller losses due to SSI, which is in line with the common belief that SSI is a favorable effect for such systems. However, the results for buildings on moderately soft soils reveal a considerable probability, up to 0.4, that SSI has an adverse effect on the structure and increases the seismic losses.     

The time reversal effect of the impulse response of crust

IntroductionTime reversal effect is a kind of reversed dynamic process in a limited space or time interval, which can be realized artificially by resetting the boundary and loading conditions. In this case the time seems to be reversed and such effect therefore is called time reversal effect, which was first proposed in and applied to the field of ultrasonic. Although the focusing of ultrasonic wave has powerful effect, it is difficult to focus in an anisotropic or homogeneous medium. Fink (19…     

Evaluation of the effect of earthquake frequency content on seismic behavior of cantilever retaining wall including soil–structure interaction

A three-dimensional backfill–structure–soil/foundation interaction phenomenon is simulated using the finite element method in order to analyze the dynamic behavior of cantilever retaining wall subjected to different ground motions. Effects of both earthquake frequency content and soil–structure interaction are evaluated by using five different seismic motions and six different soil types. The study mainly consists of three parts. In the first part, following a brief review of the problem, the finite element model with viscous boundary is proposed under fixed-base condition. In the second part, analytical formulations are presented by using modal analysis technique to provide the finite element model verification, and reasonable agreement is found between numerical and analytical results. Finally, the method is extended to further investigate parametrically the effects of not only earthquake frequency content but also soil/foundation interaction, and nonlinear time history analyzes are carried out. By means of changing the soil properties, some comparisons are made on lateral displacements and stress responses under different ground motions. It is concluded that the dynamic response of the cantilever wall is highly sensitive to frequency characteristics of the earthquake record and soil–structure interaction.     

The effect of focal depth error on moment tensor inversion

ＴｈｅｅｆｅｃｔｏｆｆｏｃａｌｄｅｐｔｈｅｒｏｒｏｎｍｏｍｅｎｔｔｅｎｓｏｒｉｎｖｅｒｓｉｏｎＬＩＳＨＥＮＧＸＵ（许力生）ＹＵＮＴＡＩＣＨＥＮ（陈运泰）ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈｙｓｉｃｓ，ＳｔａｔｅＳｅｉｓｍｏｌｏｇｉｃａｌＢｕｒｅａｕ...     

The effect of local irregular topography on seismic ground motion

Ｔｈｅｅｆｆｅｃｔｏｆｌｏｃａｌｉｒｒｅｇｕｌａｒｔｏｐｏｇｒａｐｈｙｏｎｓｅｉｓｍｉｃ　ｇｒｏｕｎｄ　ｍｏｔｉｏｎＪＩＧ－ｈｏＬＩＵ（刘晶波）（ＤｅｐａｒｔｍｅｎｔｏｆＣｉｖｉｌＥｎｇｉｎｅｅｒｉｎｇ，ＴｓｉｎｇｈｕａＵｎｉｖｅｒｓｉｔｙＢｅｉｊｉ...     

Research on the effect estimation of seismic safety evaluation

IntroductionItisdefinitelystipulatedintheLawofthePeople'sRepublicofChinaonProtectingagainstandMitigatingEarthquakeDisastersthattheseismicsafetyevaluationmustbemadeformajorprojects(includinglifelineprojects)and,accordingtotheresultsobtained,theseismicresistancerequirementsshouldbedetermined.Thenecessityofseismicsafetyevaluationhasbeenrecog-nizedgradually,butthetopicontheeffectofsafetyevaluationhasnotbeenreferredmuch.Gener-allyspeaking,althoughmostpeopleapprovethesocialeffectofsafetyevaluatio…     

The effect of the Jessica grounding on Galápagos reef fish communities adjacent to the wreck site

The grounding of the oil tanker Jessica off San Cristóbal Island, Galápagos, resulted in generally elevated rather than depressed densities of fishes adjacent to the wreck site 15 weeks post spill. Species richness of fishes declined along transects out from the wreck; however, patterns were inconsistent for different depth strata, with the most clearly defined decline evident for the intermediate 5-7 m depth stratum. Fish species attracted to the immediate wreck site, most notably the surgeonfish Prionurus laticlavius, the damselfish Microspathodon dorsalis and the angelfish Holacanthus passer, were considered to be responding either to the heterogeneity provided by the wreck structure or elevated densities of macroalgae. The fish community at the wreck site lay outside the range of variation for other sites investigated in the region; however, contrary to predictions of grounding impacts, the fish assemblage immediately adjacent to the wreckage showed greater faunal similarity to reference sites than did fish assemblage at 60-90 m distance from the grounding.     

Impact of space energetic particles on the Earth’s atmosphere (a review)

The state of the Earth??s upper atmosphere is formed with the participation of impacts by energetic particles, such as galactic cosmic rays, protons of solar proton events, and precipitation of relativistic electrons. Changes in the neutral composition and the thermal and dynamical regime of the upper atmosphere during periods of disturbances caused by the influence of energetic particles are considered.     

The effect of the Jessica grounding on subtidal invertebrate and plant communities at the Galápagos wreck site

Impacts of the grounding of the oil tanker Jessica off San Cristóbal island, Galápagos, included both effects of oil on biota and also mechanical effects associated with a shallow furrow 50 m x 30 m gouged across the rocky seafloor and wreckage strewn over 7500 m(2). The wreckage represented a minor but potentially chronic source of pollution to the surrounding environment through delayed releases of oil, antifouling compounds and other toxic chemicals, and a possible source of exotic marine taxa. Investigation at the wreck site indicated that impacts on subtidal plant and macro-invertebrate communities were largely confined within 100 m of the wreck site itself. Observed population effects included significant increases in cover of opportunistic algae (filamentous green algae, filamentous red algae and Ulva sp.) and the hydroid Ectopleura media adjacent to the wreck, while densities of the green sea urchin Lytechinus semituberculatus significantly decreased from 0.3 m(-2) adjacent to the wreck to 11 m(-2) at 100 m distance.     

Role of magnetospheric convection and precipitation in the formation of the “dusk effect” during the main phase of a magnetic storm

This paper studies the role of magnetospheric factors, such as convection and energetic electron precipitation during the formation of positive disturbances in the total electron content under the conditions of the summer evening ionosphere. à numerical model of the ionosphere and plasmasphere, where time variations in the magnetospheric convection velocity and electron precipitation parameters correspond to the main phase of a magnetic storm, has been used for this purpose. It has been indicated that the total electron content sharply increases (the “dusk effect”) in the eastern and western sectors at approximately the same geomagnetic latitudes corresponding to the subauroral zone provided that a sudden storm commencement is registered in the morning hours. local time. This peak of the total electron content is formed as a result of joint reconstruction of the magnetospheric convection pattern and energetic electron precipitation during the main phase of a storm. In this case, magnetospheric convection plays the main role, raising the F2 layer by 40–80 km into the region with a lower recombination rate.     

Study on strength reduction factors considering the effect of classification of design earthquake

Introduction The strength reduction factor is defined as the lateral yielding strength required to avoid yielding in the system when subjected to a given ground motion, to the lateral yielding strength required to maintain the displacement ductility ratio demand equal to a pre-determined target duc-tility ratio under the same ground motion. The strength reduction factors are not only the key fac-tors in determining seismic action for force-based seismic design, but also one of the key parame-t…     

A new theoretical solution of the effect of atmospheric pressure on water level

Ａｎｅｗｔｈｅｏｒｅｔｉｃａｌｓｏｌｕｔｉｏｎｏｆｔｈｅｅｆｆｅｃｔｏｆａｔｍｏｓｐｈｅｒｉｃｐｒｅｓｓｕｒｅｏｎｗａｔｅｒｌｅｖｅｌ赵鹏君Ｐｅｎｇ－ＪｕｎＺＨＡＯ（ＳｅｉｓｍｏｌｏｇｉｃａｌＢｕｒｅａｕｏｆＡｎｈｕｉＰｒｏｖｉｎｃｅ，Ｈｅｆｅｉ２３...     

Earthquake behavior of variable rupture-scale on active faults and application of the cascade-rupturing model

IntroductionThe earlier concept of the characteristic earthquakes means those earthquakes recurring along the same portion of active fault zones, and having nearly the same size, displacement and rupture scale (Schwartz, Coppersmith, 1984). However, more and more evidences have suggested that the rupture(s scale of earthquakes recurred on an individual fault portion has variability (Thatcher, 1990). For instance, the rupture of the 1906 San Francisco, California, earthquake with magnitude 8.…     

Accuracy estimates for some global analytical models of the Earth’s main magnetic field on the basis of data on gradient magnetic surveys at stratospheric balloons

Two global analytical models of the main magnetic field of the Earth (MFE) have been used to determine their potential in deriving an anomalous MFE from balloon magnetic surveys conducted at altitudes of ～30 km. The daily mean spherical harmonic model (DMSHM) constructed from satellite data on the day of balloon magnetic surveys was analyzed. This model for the day of magnetic surveys was shown to be almost free of errors associated with secular variations and can be recommended for deriving an anomalous MFE. The error of the enhanced magnetic model (EMM) was estimated depending on the number of harmonics used in the model. The model limited by the first 13 harmonics was shown to be able to lead to errors in the main MFE of around 15 nT. The EMM developed to n = m = 720 and constructed on the basis of satellite and ground-based magnetic data fails to adequately simulate the anomalous MFE at altitudes of 30 km. To construct a representative model developed to m = n = 720, ground-based magnetic data should be replaced by data of balloon magnetic surveys for altitudes of ～30 km. The results of investigations were confirmed by a balloon experiment conducted by Pushkov Institute of Terrestrial Magnetism, Ionosphere, and Radio Wave Propagation of the Russian Academy of Sciences and the Moscow Aviation Institute.