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The high-velocity wind caused by a methane-air explosion is one of the important hazardous effects in explosion events of coal mines, and, however, until now it has not been received much attention from scientific works. The paper aims to discuss this issue.

In consideration of the difficulties in observing particle velocities of high-velocity flows, this work presented a study to reveal the regularity during a methane-air explosion happening in the tunnel of coal mine through the numerical analysis approach.

The strong wind caused by a methane-air explosion is a significant hazard and can cause damage in the accidents of methane-air explosion in underground coal mines, especially at structural opening, according to this work. Obtained results show that maximum particle velocity of the high-velocity wind occurs in the outside region of the premixed area, with a peak value of 400∼500 m/s, and the peak velocity of the high-velocity wind decreases exponentially with distance beyond the premixed area.

The objective of this work was to examine the effect of wind caused by a methane-air explosion in a tunnel. Other information, such as shock wave and flame and temperature distribution, has been reported in the previous literatures. However, in the accidents of methane-air explosion in underground coal mines, some phenomena (structural opening is destroyed badly) can not be understood by using shock wave and flame and temperature distribution caused by the explosion. The strong wind caused by a methane-air explosion is another significant hazard and can cause damage in the methane-air explosion accidents in underground coal mines, especially at structural opening, according to this work.

This paper aims to design an optimum vertical axis wind turbine (VAWT) and assess its techno-economic performance for wind energy harvesting at high-speed railway in Malaysia.

This project adopted AutoCAD and ANSYS modeling tools to design and optimize the blade of the turbine. The site selected has a railway of 30 km with six stops. The vertical turbines are placed 1 m apart from each other considering the optimum tip speed ratio. The power produced and net present value had been analyzed to evaluate its techno-economic viability.

Computational fluid dynamics (CFD) analysis of National Advisory Committee for Aeronautics (NACA) 0020 blade has been carried out. For a turbine with wind speed of 50 m/s and swept area of 8 m², the power generated is 245 kW. For eight trains that operate for 19 h/day with an interval of 30 min in nonpeak hours and 15 min in peak hours, total energy generated is 66 MWh/day. The average cost saved by the train stations is RM 16.7 mil/year with battery charging capacity of 12 h/day.

Wind energy harvesting is not commonly used in Malaysia due to its low wind speed ranging from 1.5 to 4.5 m/s. Conventional wind turbine requires a minimum cut-in wind speed of 11 m/s to overcome the inertia and starts generating power. Hence, this paper proposes an optimum design of VAWT to harvest an unconventional untapped wind sources from railway. The research finding complements the alternate energy harvesting technologies which can serve as reference for countries which experienced similar geographic constraints.

The continent of Antarctica consists of 14 million km², roughly equivalent to the whole of South America, and is of immense interest to humanity, in particular to the countries of the Antarctic Treaty. The Antarctic continent is the continent of superlatives: it is almost isolated from the rest of the continents, and is severely cold, windy, and dry. In winter, the Antarctic area increases to nearly 32 million km², because of formation of a 1,000km wide ice‐belt. The average depth of ice on the continent is in the order of 2,000m, and in the transantarctic region this depth is 4,800 meters. Antarctica is the biggest sweet water reservoir of the planet earth. Icebergs are common and huge ones (190km in length and 130km wide) have also been observed. The minimum temperature recorded (–89.2°C) at Vostok (Russian base) on 21 July 1983 is also the minimum recorded environmental temperature on the planet earth. Because of extreme temperature variations the Antarctic winds have high velocity. The environment is very dry and at the center of the continent the dryness is of the same magnitude as in the driest desert anywhere on the planet. This is the only uninhabited continent of the planet, except for some 50 research bases which cover an insignificant area located on the continent and the Antarctica Peninsula. Because of its economic, strategic, geopolitical, scientific, meteorological, and oceanographic importance and possible exploitation in the future, Antarctica has been attracting greater attention every day. Antarctica is basically concentrated around the South Pole and it touches the Atlantic, Pacific, and Indian Oceans. Brazil, in common with many other nations, has geopolitical interests and in untapped mineral deposits (considerable deposits of coal, petroleum, gas). In the south, where the Atlantic, Pacific and Indian Oceans meet, the cold water of Antarctica is the habitat housing hundreds of species of sea life. Unrestricted and unbalanced exploitation of Antarctica could cause changes in the meteorological and oceanographic balance. In the present paper, the Brazilian Antarctic Program, and summarized results of studies of Antarctic soil, rocks, and sediments are reported.

Discusses the distress of mine rope‐wires, under the diverse states of stresses and strains of physical, chemical and mechanical origin. Mine rope‐wires undergo complicated cycles of stresses and strains inside the depth of coal and metal mines. This assumes special significance during summer inside the deeper mines. Summarizes recent studies in this field and compares their results.

Arid ecosystem covers one third of the Earth's surface and is the home town of majority of the population of the world. This ecosystem is also important because it has significant roles in land and water resources management. However, due to anthropogenic land use activities or shifting climate conditions, the features of the ecosystem change and cause diminished vegetative cover, reduced productivity, increased soil erosion, invasion of exotics, and loss of native species. Moreover, in the recent years, earth's vegetative cover may exceed the ecosystem's capacity to adapt, which happens through the consequence of rapid land degradation along with desertification. Therefore, this chapter provides how different regions endeavor with this arid ecosystem by performing various adaptation practices.

The purpose of this paper is to present a systematic approach for the evaluation and selection of curtain wall systems for medium-high rise building construction.

The authors have identified the different types of curtain wall systems that are commonly used in the building construction industry in Saudi Arabia; examined the various performance as well as financial and non-financial criteria affecting the evaluation and selection of these systems; and subjected the identified different types of curtain wall systems to several filtering processes, namely feasibility ranking, evaluation by comparison and weighted evaluation to facilitate making a decision on the most suitable system to select.

The analysis of the collected data indicated that the precast concrete curtain wall system is considered to be the first choice. The second choice is the prefabricated brick panel curtain wall system.

Curtain walls are the most recognized elements of contemporary structures today. There exists ample variety of materials and designs that could be utilized for the development of these building elements. This paper is of practical value to project owners, architects and design professionals endeavoring on the process of selecting and specifying curtain wall systems in their projects.

To provide a review of the general aspects of tsunamis and the specific aspects of the 2004 tsunami impacts on the coastal areas of India and surrounding islands.

The approach is a general discussion of the 2004 tsunami and its effects in areas in South East Asia, followed by the specific impacts in the Andaman and Nicobar Islands, including the damage to water supply and power systems, and a situation analysis of the communities, land and housing.

The impact of the 2004 tsunami highlights the vulnerability of the coastal areas and islands of India. The multi‐hazard situation existing on the sea coast of the mainland as well as in the islands of Andaman and Nicobar require a holistic multi‐hazard mitigation approach as a long term measure. The recovery programs presently in hand are being planned taking the multi‐hazard situation in view, so as to provide protection from such hazards in future.

Provides a review of the effects of the 2004 tsunami in the coastal areas and islands near India.

Amongst all classes of unmanned aircraft system (UAS), the rise of the Mini UAS class is the most dominant. Mini UASs are field-deployable systems and hence are not expected to operate from a runway. Therefore, the operating terrain plays an important role in the deployment and employment of the Mini UAS. However, there is limited published work in this area. The impact of terrain is more critical for military applications than civilian applications. The purpose of this paper is to explore the implications of various types of terrain on the employment and deployment of Mini UAS.

This paper explores the implications of various types of terrain on the employment and deployment of Mini UAS.

Mini UAS with field deployable requirements is often launched within the tactical battle area in case of military applications or in close proximity to the intended target area for civilian applications. Due to the size and weight of the Mini UAS, launch and recovery becomes an important factor to be considered. Rotary wing or fixed-wing vertical take-off and landing configuration UAS overcomes the limitations of Mini UAS and hence it is the preferred option. Impact of the terrain is significantly higher for military applications as compared to civil applications. Mountain terrain is the most challenging for Mini UAS operations.

This paper will help the designers configure the UAS as per the operating terrain.

Terrain affects the deployment and employment of Mini UAS and the capabilities of the system with respect to terrain in which it is expected to operate must be considered during the design of a Mini UAS. The paper will help the designers configure the UAS as per the operating terrain.

A fluid moving system for producing substantially laminar flow of ambient fluid over and adjacent a substantially smooth surface exposed to the fluid which comprises a multiplicity of electrode elements mounted in spaced relationship to one another adjacent to the surface and electrically insulated from one another and constituting a series of elements extending along a portion of the surface. The means comprise a multiplicity of sharp points on predetermined ones of the elements oriented in the direction of flow of fluid over the elements for producing charged particles adjacent to the predetermined ones of the elements. All of the sharp points for each of the elements lie substantially in a plane perpendicular to the direction of fluid flow and equidistant from the next element in the direction of flow whereby the production of charged particles by a corona‐type discharge is facilitated at each of the sharp points. Electric exciting means connected with the electrode elements produce progressively changing electric potentials along the surface thereby creating an electric potential field for propelling charged particles dispersed in the ambient fluid progressively from one electrode clement toward the next and induce a surface layer fluid flow over that portion of the surface. Certain of the predetermined elements comprise conducting bars having the sharp points arranged in two sets pointing in opposite directions, auxiliary electrodes spaced from the bars one on one side and one on the other of each of the bars, and switching means for selectively connecting each of the bars alternatively to the auxiliary electrode on either side thereof for reversing the direction of corona discharge and the direction of charged particle propulsion.

Aims to compare the energy embodied in office buildings varying in height from a few storeys to over 50 storeys. The energy embodied in substructure, superstructure and finishes elements was investigated for five Melbourne office buildings of the following heights: 3, 7, 15, 42 and 52 storeys. The two high‐rise buildings have approximately 60 percent more energy embodied per unit gross floor area (GFA) in their materials than the low‐rise buildings. While building height was found to dictate the amount of energy embodied in the “structure group” elements (upper floors, columns, internal walls, external walls and staircases), other elements such as substructure, roof, windows and finishes seemed uninfluenced.