Fog

The distributed computing attempts to improve perfor-mance in large-scale computing problems by resource sharing. Moreover, rising low-cost computing power coupled with advances in communications/networking and the advent of big data, now enables new distributed computing paradigms such as Cloud, Jungle and Fog computing. Cloud computing brings a number of advantages to consumers in terms of accessibility and elasticity. It is based on centralization of resources that possess huge processing power and storage capacities. Fog computing, in contrast, is pushing the frontier of computing away from centralized nodes to the edge of a network, to enable computing at the source of the data. On the other hand, Jungle computing includes a simultaneous combination of clusters, grids, clouds, and so on, in order to gain maximum potential computing power. To understand these new buzzwords, reviewing these paradigms together can be useful. Therefore, this paper describes the advent of new forms ...

Daytime fog at Maddens Plain along the Illawarra escarpment south of Sydney between 1975-1990 can be related either to expansive cooling of air directed onshore against the escarpment, or to cloud under conditions of convective instability.  Because of ground drainage, radiation fogs rarely persist into daytime.  Principal component analysis of a suite of regional and local meteorological variables and fog parameters indicates that fog is related to the presence of macro-scale circulation, namely east coast lows, the passage of cold fronts or monsoonal intrusions of low pressure over the interior of New South Wales.  The development and persistence of these lows are linked inseparably to the positioning and movement of anticyclonic cells across the continent.  Surprisingly there appears to be little consistent relationship of either fog characteristics or the synoptic patterns favouring fog formation to phases of the Southern Oscillation.

106 Archaeology Research in Underwater Archaeology: some challenges and approaches for the future Mark Staniforth Maritime Archaeology Program, Department of Archaeology, Flinders University, GPO Box 2100, Adelaide, SA, 5001, AUSTRALIA Abstract. Abstract: This ...

In a scenario of climate changes and increasing stress upon available fresh water resources like rivers, lakes and aquifers, collecting fog water is a promising yet relatively unexplored potentiality. Providing sufficient water and reducing water extraction's environmental impact at the same time can be a challenge with conventional ways, but fog harvesting technology presents itself as a powerful and efficient alternative. Water availability profoundly determined regional economic benefit, social relations and it also influenced environmental security and ecosystem services. Underdeveloped countries have been dealing with water scarcity issue for decades, but also wealthy countries will have to face the water crisis soon, due to unsustainable development processes. A review of the state of the art highlights the most relevant parameters to deal with when discussing about fog water harvesting. In regions with frequent fog events, this technology already proved to be a sustainable drinking water resource for rural communities and their low per capita water usage was provided by basic devices utilization. Nevertheless, in this paper, different fog water harvesting applications are investigated, besides the already existing freshwater collection, reforestation and agricultural use. Further options , such as building components, outdoor activities and domestic devices are considered, according to different parameters, such as economic benefits, possibility of standardized production, life cycle and market attractiveness. A desirable novel concept would become relevant in specific contexts, thanks to multiple functions, offering locals designed and customized solutions. Also noteworthy are the landscape impact of such devices and the effects of the project in terms of places regeneration, raising awareness and " green " conscience creation. The study of local climatic data and improvement in fog collector applications, integration with architectural and landscape design, will expand the regions where fog harvesting can be applied and its sustainable improvements.

Determining how to structure vehicular network environments can be done in various ways. Here, we highlight vehicle networks’ evolution from vehicular ad-hoc networks (VANET) to the internet of vehicles (IoVs), listing their benefits and limitations. We also highlight the reasons in adopting wireless technologies, in particular, IEEE 802.11p and 5G vehicle-to-everything, as well as the use of paradigms able to store and analyze a vast amount of data to produce intelligence and their applications in vehicular environments. We also correlate the use of each of these paradigms with the desire to meet existing intelligent transportation systems’ requirements. The presentation of each paradigm is given from a historical and logical standpoint. In particular, vehicular fog computing improves on the deficiences of vehicular cloud computing, so both are not exclusive from the application point of view. We also emphasize some security issues that are linked to the characteristics of these paradigms and vehicular networks, showing that they complement each other and share problems and limitations. As these networks still have many opportunities to grow in both concept and application, we finally discuss concepts and technologies that we believe are beneficial. Throughout this work, we emphasize the crucial role of these concepts for the well-being of humanity.

Visibility is critical to the task of driving and reduction in visibility due to fog, smoke or other weather events such as heavy rain is a major traffic operation and safety concern. In Florida, these conditions could be a result of sudden dense fog, fires (whether wild or controlled), and heavy pockets of rain or hail. Real time measurement of visibility may help in warning the drivers when the visibility falls below certain acceptable levels. Devices measuring visibility are the key toward that objective. This paper reports on the design of a visibility warning and detection system that detects any reduction in visibility below a certain limit that would be considered hazardous for normal traffic flow conditions. This system can also respond accordingly in real time to convey specific warning messages to drivers in an effective way and report this information to the appropriate Traffic Management Center (TMC). The innovation in this system is that it was developed from components that are inexpensive and available commercially. Also, this system can be employed as portable or fixed system. A fixed system might be useful in areas that tend to have dense fog (for example, rural sections of freeways). However, the portable system can be used every time a wildfire occurs close to a highway. The system components and a preliminary testing for the system’s performance are discussed and presented in this paper.

Today, there exist intercommunication and interconnection among numerous devices as a result of the emergence of Internet of Things (IoT) that has caused unprecedented production of significant data, referred to as data explosion. Over the years, cloud computing has played a critical part in processing and storing such data. However, cloud computing still experiences various challenges such as limitation of network bandwidth and real-time increasing demands that cannot be overcome solely by cloud computing technology. Hence, fog computing-a novel computing paradigm emerged as a complement to the solution of cloud computing. Essentially, fog computing enhances the services of the cloud to the edge of the network by ensuring end-users and edge devices communicate, compute, and store data efficiently. Such achievements are achieved by improving security, network bandwidth, mobility, as well as low latency. Thus, the current research paper surveys and summarizes fog computing and cloud computing to depict \their architectures, main technologies, applications, as well as related security challenges. Firstly, the paper explores the fog computing architecture in relation to cloud computing architecture before discussing their key technologies such as computing and communication. It goes further to address several applications of the two technologies. Finally, the paper provides related security issues that require further research to enhance technologies.

Contains the viewgraphs and other materials for the 48 papers presented at the 18th annual review conference on atmospheric transmission models held at the geophysics directorate, Phillips Laboratory (AFMC), Hanscom AFB, MA ON: 6-8 June 1995.

... Drying of the atmosphere above about 800 hPa (Fig. 4), with the departure of deep clouds in satellite imagery (Fig. 7), would allow for radiational cooling at the top of a fog (eg, Jiusto andLala 1980; Brown 1987; Fitzjarrald and Lala 1989; Croft et al. 1997). ...

Today, there exist intercommunication and interconnection among numerous devices as a result of the emergence of Internet of Things (IoT) that has caused unprecedented production of significant data, referred to as data explosion. Over the years, cloud computing has played a critical part in processing and storing such data. However, cloud computing still experiences various challenges such as limitation of network bandwidth and real-time increasing demands that cannot be overcome solely by cloud computing technology. Hence, fog computing-a novel computing paradigm emerged as a complement to the solution of cloud computing. Essentially, fog computing enhances the services of the cloud to the edge of the network by ensuring end-users and edge devices communicate, compute, and store data efficiently. Such achievements are achieved by improving security, network bandwidth, mobility, as well as low latency. Thus, the current research paper surveys and summarizes fog computing and cloud computing to depict \their architectures, main technologies, applications, as well as related security challenges. Firstly, the paper explores the fog computing architecture in relation to cloud computing architecture before discussing their key technologies such as computing and communication. It goes further to address several applications of the two technologies. Finally, the paper provides related security issues that require further research to enhance technologies

With the objective of understanding fog water chemistry and sources contribution at an IGP outflow location (coastal Bhola Island, Bangladesh), we have collected fifteen fog water samples during winter 2016-17. Major ions, trace metals with physical properties (pH and electrical conductivity) were measured. The pH (7.12± 0.20) was slightly alkaline, which was much higher than rest of the world, but consistent with IGP region. Ca2+ containing species were the main contributor to the neutralization process of fog water, followed by K+ and Mg2+. The neutralizing species were derived mainly from soil dusts with a minor contribution from sea salt. HYSPLIT trajectory analysis revealed that substantial influences of the contaminated air mass in fog water from IGP. However, higher enrichment factors and parentage source contribution of SO42- (76.9), NO3- (99.3) and trace metals (Mn, Cu, and Zn) suggested significant anthropogenic contribution in the fog water at this Indo-Gangetic Outflow Location.

The occurrence of airborne biological particles (bacteria, yeasts and moulds) in fog water and the influence of temperature and fog chemical composition and acidity on their concentration are described in this paper. Our results show that the concentration of airborne bacteria and yeasts is enriched in foggy conditions up to two orders of magnitude compared to clear air conditions, while concentration of moulds is not influenced by the presence of fog. These results support the hypothesis that fog droplets act as culture media for airborne biological particles, i.e. they represent an atmospheric source of secondary biological particles.

To gain insights into the poorly understood phenomenon of precipitation fog, this study assesses the evaporation of freely falling drops departing from equilibrium as a possible contributing factor to fog formation in rainy conditions. The study is based on simulations performed with a microphysical column model describing the evolution of the temperature and mass of evaporating raindrops within a Lagrangian reference frame. Equilibrium defines a state where the latent heat loss of an evaporating drop is balanced by the sensible heat flux from the ambient air, hence defining a steady-state drop temperature. Model results show that the assumption of equilibrium leads to small but significant errors in calculated precipitation evaporation rates for drops falling in continuously varying ambient near-saturated or saturated conditions. Departure from equilibrium depends on the magnitude of the vertical gradients of the ambient temperature and moisture as well as the drop-size-dependent t...