Search results for "snow"

Weighted pointwise Hardy inequalities

2009

We introduce the concept of a visual boundary of a domain �¶ �¼ Rn and show that the weighted Hardy inequality  �¶ |u|pd�¶ �A.p  C  �¶ |�Þu|pd�¶ �A, where d�¶(x) = dist(x, �Ý�¶), holds for all u �¸ C �� 0 (�¶) with exponents �A < �A0 when the visual boundary of �¶ is sufficiently large. Here �A0 = �A0(p, n, �¶) is explicit, essentially sharp, and may even be greater than p . 1, which is the known bound for smooth domains. For instance, in the case of the usual von Koch snowflake domain the sharp bound is shown to be �A0 = p . 2 + �E, with �E = log 4/ log 3. These results are based on new pointwise Hardy inequalities.

The Impact of COVID-19 Pandemic and Lockdown Measures on Quality of Life among Italian General Population

2021

The COVID-19 pandemic that has hit the world in the year 2020 has put a strain on our ability to cope with events and revolutionized our daily habits. On 9 March, Italy was forced to lockdown to prevent the spread of the infection, with measures including the mandatory closure of schools and nonessential activities, travel restrictions, and the obligation to spend entire weeks in the same physical space. The aim of this study was to assess the impact of the COVID-19 pandemic and lockdown measures on quality of life (QoL) in a large Italian sample, in order to investigate possible differences in QoL levels related to both demographic and pandemic-specific variables. A total of 2251 Italian a…

The impact of volcanogenic emissions of major and trace elements at Mt. Etna, Sicily, on precipitation (rain and snow) chemistry

2009

Mosses as biomonitors of atmospheric heavy metal deposition : Spatial patterns and temporal trends in Europe

2010

In recent decades, mosses have been used successfully as biomonitors of atmospheric deposition of heavy metals. Since 1990, the European moss survey has been repeated at five-yearly intervals. Although spatial patterns were metal-specific, in 2005 the lowest concentrations of metals in mosses were generally found in Scandinavia, the Baltic States and northern parts of the UK ; the highest concentrations were generally found in Belgium and south-eastern Europe. The recent decline in emission and subsequent deposition of heavy metals across Europe has resulted in a decrease in the heavy metal concentration in mosses for the majority of metals. Since 1990, the concentration in mosses has decli…

Improvement of snow physical parameters retrieval using SAR data in the Arctic (Svalbard)

2018

International audience; Arctic snow cover dynamics offer a changing face in terms of temporal duration andwater equivalent, due to recent climate change conditions (Callaghan et al., 2011; Lemke & Jacobi,2012). Indeed, the Arctic is now experiencing some of the most rapid and severe climate change onearth. In this context, innovative and improved methods are helpful to enhance management of thesnow-pack resource for climate research, hydrology and human activities. The characteristics of Arcticsnow are different from “temperate” snow (i.e. the Alps), in terms of thickness, internal structure, thermalconductivity, and metamorphism. Ground observation often indicates wind slab at the snow sur…

Identification of magnetic particulates in road dust accumulated on roadside snow using magnetic, geochemical and micro-morphological analyses

2010

The aim of this study is to test the applicability of snow surveying in the collection and detailed characterization of vehicle-derived magnetic particles. Road dust extracted from snow, collected near a busy urban highway and a low traffic road in a rural environment (southern Finland), was studied using magnetic, geochemical and micro-morphological analyses. Significant differences in horizontal distribution of mass specific magnetic susceptibility (χ) were noticed for both roads. Multi-domain (MD) magnetite was identified as the primary magnetic mineral. Scanning electron microscope (SEM) analyses of road dust from both roads revealed: (1) angular-shaped particles (diameter ∼1–300 μm) mo…

Intelligent system for electrical heating control based on optical precipitation sensor

2018

Abstract The paper presents testing results of the SCADA system IntelHeat introduced at the Latvian Railways for automated heating control of railway points during winters with the purpose of electricity saving by optimized real-time assignment of heating levels. The system is based on innovative optical sensors of precipitation detecting rain and snow particles using diffuse and specular reflection channels. The results of trial exploitation demonstrated the ability of the IntelHeat system to manage points heating flexibly in accordance with changes of weather conditions and correspondence with archived meteorological data.

Dataset of trace elements concentrations in snow samples collected in Jelgava City (Latvia) in December 2020

2021

Abstract The data set provided in this article consist of two repeated data sets of chemical elements concentrations in snow samples. The snow samples were collected in Jelgava city at December 15th with 5 day exposition time. Snow samples were collected in 59 monitoring points in Jelgava city and in one sample in rural area monitoring point as control. The collected snow samples were melted, acidified with HNO3 and analysed with ICP-MS. The samples were analysed Aluminium (Al), Silicon (Si), Chrome (Cr), Manganese (Mn), Iron (Fe), Nickel (Ni), Copper (Cu), Zinc (Zn), Arsenic (As), Molybdenum (Mo), Cadmium (Cd), Barium (Ba), Tungsten (W), Lead (Pb). The collected data are with fundamental s…

Growth of Ice Particles by Accretion and Ice Particle Melting

2010

In Chapter 13, we discussed the growth of snow crystals by vapor diffusion, and in Chapter 14, we described the manner with which snow crystals interact with other snow crystals and with drops. In this chapter, we shalllook closer at the growth of ice particles by the accretion of supercooled drops, at the formation of snow flakes by the collision of snow crystals, and also consider the physics of melting of individual ice particles.

Solidago canadensis un Heracleum sosnowskyi ēterisko eļļu herbicidālā un fungicidālā iedarbība

2022

Strauja invazīvo augu sugu izplatīšanās tiek uzskatīta par vienu no galvenajiem bioloģiskās daudzveidības samazināšanās virzītājspēkiem, kā rezultātā tiek traucēta ekosistēmu pakalpojumu nodrošināšana, kas rada negatīvas ekoloģiskās sekas, ekonomiskus zaudējumus un kaitējumu cilvēka veselībai. Invazīvo augu sugu ierobežošana ir dārga un bieži vien ekonomiski neizdevīga, kā arī ķīmiskā ierobežošana var radīt draudus cilvēkam, tāpēc izdevīgāk būtu šīs sugas ilgtspējīgi izmantot, vienlaikus cenšoties nepieļaut jaunu invazīvo augu sugu ienākšanu Latvijā. Latvijā izplatītāko invazīvo augu sugu Sosnovska latvāņa un Kanādas zeltslotiņas augu daļas ir bagātas ar ēterisko eļļu, kurai var būt herbici…