Vertical Moist Thermodynamic Structure and Spatial–Temporal Evolution of the MJO in AIRS Observations

The atmospheric moisture and temperature profiles from the Atmospheric Infrared Sounder (AIRS)/Advanced Microwave Sounding Unit on the NASA Aqua mission, in combination with the precipitation from the Tropical Rainfall Measuring Mission (TRMM), are employed to study the vertical moist thermodynamic structure and spatial–temporal evolution of the Madden–Julian oscillation (MJO). The AIRS data indicate that, in the Indian Ocean and western Pacific, the temperature anomaly exhibits a trimodal vertical structure: a warm (cold) anomaly in the free troposphere (800–250 hPa) and a cold (warm) anomaly near the tropopause (above 250 hPa) and in the lower troposphere (below 800 hPa) associated with enhanced (suppressed) convection. The AIRS moisture anomaly also shows markedly different vertical structures as a function of longitude and the strength of convection anomaly. Most significantly, the AIRS data demonstrate that, over the Indian Ocean and western Pacific, the enhanced (suppressed) convection is generally preceded in both time and space by a low-level warm and moist (cold and dry) anomaly and followed by a low-level cold and dry (warm and moist) anomaly. The MJO vertical moist thermodynamic structure from the AIRS data is in general agreement, particularly in the free troposphere, with previous studies based on global reanalysis and limited radiosonde data. However, major differences in the lower-troposphere moisture and temperature structure between the AIRS observations and the NCEP reanalysis are found over the Indian and Pacific Oceans, where there are very few conventional data to constrain the reanalysis. Specifically, the anomalous lower-troposphere temperature structure is much less well defined in NCEP than in AIRS for the western Pacific, and even has the opposite sign anomalies compared to AIRS relative to the wet/dry phase of the MJO in the Indian Ocean. Moreover, there are well-defined eastward-tilting variations of moisture with height in AIRS over the central and eastern Pacific that are less well defined, and in some cases absent, in NCEP. In addition, the correlation between MJO-related midtropospheric water vapor anomalies and TRMM precipitation anomalies is considerably more robust in AIRS than in NCEP, especially over the Indian Ocean. Overall, the AIRS results are quite consistent with those predicted by the frictional Kelvin–Rossby wave/conditional instability of the second kind (CISK) theory for the MJO

Phase transition in nanomagnetite

Recently, the application of nanosized magnetite particles became an area of growing interest for their potential practical applications. Nanosized magnetite samples of 36 and 9 nm sizes were synthesized. Special care was taken on the right stoichiometry of the magnetite particles. Mössbauer spectroscopy measurements were made in 4.2–300 K temperature range. The temperature dependence of the intensities of the spectral components indicated size dependent transition taking place in a broad temperature range. For nanosized samples, the hyperfine interaction values and their relative intensities changed above the Verwey transition temperature value of bulk megnetite. The continuous transition indicated the formation of dendritelike granular assemblies formed during the preparation of the samples

Solid Surface Structure Affects Liquid Order at the Polystyrene/SAM Interface

We present a combined x-ray and neutron reflectivity study characterizing the interface between polystyrene (PS) and silanized surfaces. Motivated by the large difference in slip velocity of PS on top of dodecyl-trichlorosilane (DTS) and octadecyl-trichlorosilane (OTS) found in previous studies, these two systems were chosen for the present investigation. The results reveal the molecular conformation of PS on silanized silicon. Differences in the molecular tilt of OTS and DTS are replicated by the adjacent phenyl rings of the PS. We discuss our findings in terms of a potential link between the microscopic interfacial structure and dynamic properties of polymeric liquids at interfaces

Solidification of Al-Sn-Cu based immiscible alloys under intense shearing

The official published version of the Article can be accessed from the link below - Copyright @ 2009 The Minerals, Metals & Materials Society and ASM InternationalThe growing importance of Al-Sn based alloys as materials for engineering applications necessitates the development of uniform microstructures with improved performance. Guided by the recently thermodynamically assessed Al-Sn-Cu system, two model immiscible alloys, Al-45Sn-10Cu and Al-20Sn-10Cu, were selected to investigate the effects of intensive melt shearing provided by the novel melt conditioning by advanced shear technology (MCAST) unit on the uniform dispersion of the soft Sn phase in a hard Al matrix. Our experimental results have confirmed that intensive melt shearing is an effective way to achieve fine and uniform dispersion of the soft phase without macro-demixing, and that such dispersed microstructure can be further refined in alloys with precipitation of the primary Al phase prior to the demixing reaction. In addition, it was found that melt shearing at 200 rpm and 60 seconds will be adequate to produce fine and uniform dispersion of the Sn phase, and that higher shearing speed and prolonged shearing time can only achieve minor further refinement.This work is funded by the EPSRC and DT

A Sorted Datalog Hammer for Supervisor Verification Conditions Modulo Simple Linear Arithmetic

In a previous paper, we have shown that clause sets belonging to the HornBernays-Sch\"onfinkel fragment over simple linear real arithmetic (HBS(SLR))can be translated into HBS clause sets over a finite set of first-orderconstants. The translation preserves validity and satisfiability and it isstill applicable if we extend our input with positive universally orexistentially quantified verification conditions (conjectures). We call thistranslation a Datalog hammer. The combination of its implementation inSPASS-SPL with the Datalog reasoner VLog establishes an effective way ofdeciding verification conditions in the Horn fragment. We verify supervisorcode for two examples: a lane change assistant in a car and an electroniccontrol unit of a supercharged combustion engine. In this paper, we improve ourDatalog hammer in several ways: we generalize it to mixed real-integerarithmetic and finite first-order sorts; we extend the class of acceptableinequalities beyond variable bounds and positively grounded inequalities; andwe significantly reduce the size of the hammer output by a soft typingdiscipline. We call the result the sorted Datalog hammer. It not only allows usto handle more complex supervisor code and to model already consideredsupervisor code more concisely, but it also improves our performance on realworld benchmark examples. Finally, we replace the before file-based interfacebetween SPASS-SPL and VLog by a close coupling resulting in a single executablebinary.<br

A Sorted Datalog Hammer for Supervisor Verification Conditions Modulo Simple Linear Arithmetic

International audienceAbstract In a previous paper, we have shown that clause sets belonging to the Horn Bernays-Schönfinkel fragment over simple linear real arithmetic (HBS(SLR)) can be translated into HBS clause sets over a finite set of first-order constants. The translation preserves validity and satisfiability and it is still applicable if we extend our input with positive universally or existentially quantified verification conditions (conjectures). We call this translation a Datalog hammer. The combination of its implementation in SPASS-SPL with the Datalog reasoner VLog establishes an effective way of deciding verification conditions in the Horn fragment. We verify supervisor code for two examples: a lane change assistant in a car and an electronic control unit of a supercharged combustion engine. In this paper, we improve our Datalog hammer in several ways: we generalize it to mixed real-integer arithmetic and finite first-order sorts; we extend the class of acceptable inequalities beyond variable bounds and positively grounded inequalities; and we significantly reduce the size of the hammer output by a soft typing discipline. We call the result the sorted Datalog hammer. It not only allows us to handle more complex supervisor code and to model already considered supervisor code more concisely, but it also improves our performance on real world benchmark examples. Finally, we replace the before file-based interface between SPASS-SPL and VLog by a close coupling resulting in a single executable binary

Hysteresis of tropical forests in the 21st century

Tropical forests modify the conditions they depend on through feedbacks at different spatial scales. These feedbacks shape the hysteresis (history-dependence) of tropical forests, thus controlling their resilience to deforestation and response to climate change. Here, we determine the emergent hysteresis from local-scale tipping points and regional-scale forest-rainfall feedbacks across the tropics under the recent climate and a severe climate-change scenario. By integrating remote sensing, a global hydrological model, and detailed atmospheric moisture tracking simulations, we find that forest-rainfall feedback expands the geographic range of possible forest distributions, especially in the Amazon. The Amazon forest could partially recover from complete deforestation, but may lose that resilience later this century. The Congo forest currently lacks resilience, but is predicted to gain it under climate change, whereas forests in Australasia are resilient under both current and future climates. Our results show how tropical forests shape their own distributions and create the climatic conditions that enable them

Анализ основных показателей годовой финансовой отчетности предприятия

Актуальность темы обусловлена необходимостью постоянного мониторинга показателей финансовой отчетности с целью координирования деятельности компании. Объектом исследования в данной работе является ООО "РСТ". Предмет исследования – анализ финансовой отчетности ООО "РСТ". Цель выпускной квалификационной работы – анализ основных показателей годовой финансовой отчетности ООО "РСТ" и определение направлений совершенствования внутренней и внешней политики.The relevance of the topic is due to the need for constant monitoring of financial reporting indicators in order to coordinate the company's activities. The object of research in this paper is LLC "RST". The subject of the study is the analysis of the financial statements of LLC "RST". The purpose of the final qualification work is to analyze the main indicators of the annual financial statements of LLC "RST" and identify areas for improving domestic and foreign policy