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Hyderabad is one of the fastest growing Indian megacities which have significant impact on its environment. The surface and groundwater resources are severely affected by uncontrolled expansion and densification of the city. For the better understanding, recovery and to prevent future deterioration of these significance resources, it is necessary to have knowledge of the impact of urban growth in various ways on environment. Historical groundwater level and quality data obtained from different sources as well as by field study data is used for this analysis. In some cases missing data points were interpolated and verified by providing certain criteria. The map of rate of groundwater level change per year showed the locations of recharge activity by sewage and other effluents as well as overexploitations by industrial and some upper middle class residential areas. The results obtained from groundwater quality analysis are then compared with the BIS (Bureau of India) as well as WHO (World Health Organization) standards for drinking water. It had been observed that many water samples had heavy metal elements and bacterial formation above permissible limits and it is not suitable for drinking purpose. The water samples obtained from locations which do not qualify for drinking water use according to WHO as well as BIS standards are identified. These results are then overlapped with map of rate of groundwater level change to establish the relation between urban groundwater recharge and its effect on groundwater quality. [ABSTRACT FROM AUTHOR]

In developing and newly industrialized countries, population growth and migration contribute immensely to the development of megacities and mega urban areas. In most cases, the rapid development of cities has far-reaching consequences for the ecosystem in general and the hydrological cycle in particular. The developments in China within the last decades show an interesting, but complex setting. Massive and rapidly occurring land use changes in the economically booming South-Chinese Pearl River Delta result in rising hazards and risks for the urban water resources and often in a severe deterioration of water quality. The quantity and quality of local groundwater sources is, however, much less investigated than the situation of the surface waters. In order to supporting a better protection of the urban groundwater resources, the aims of this article are to analyze the vulnerability of the groundwater and the potential hazards and risks for groundwater resulting from land use changes - taking Guangzhou as a case study area. [ABSTRACT FROM AUTHOR]

This interdisciplinary paper aims at Guangzhou's development and its effects on surface and groundwater quality taking the new city axis as an example. Qualitative morphological analyses, field mappings, interviews and water sampling of standard in-situ and various hydrochemical parameters were conducted between 2007 and 2009 in order to examine the following research questions: Which types of land use can be found within the new city axis? Are there infrastructure differences of water supply and wastewater disposal? How does land use affect the quality of surface and groundwater? How do inhabitants perceive and appraise settlement structures, infrastructures and environmental quality and how do they cope with their individual situation? Within four small-scale research areas, so-called urban units, different stages and types of development and factors influencing the water resources as well as spatial variations of water quality could be identified. Deficits in city planning, water supply and sanitation lead, for example, to informal building expansion and groundwater use as well as to high concentrations of coliform bacteria in urban rivers. A wide range of ecological and social vulnerabilities became obvious. [ABSTRACT FROM AUTHOR]

In this paper, white Portland cement was used as an experimental material. Prismatic specimens with pre-existing flaws at different angles of inclination ( α) varying through 0°, 30°, 45°, 60°, 75° to 90° and cylindrical specimens with different numbers of pre-existing flaws ( n) varying through 0, 1, 2 to 3 were tested under uni-axial compression tests. Crack initiation, propagation, coalescence, and failure were observed. The corresponding analytical expression for the stress intensity factor under uni-axial compression was derived, the coefficient of friction and the stress intensity factor of the specimens on the surfaces of the crack were analysed, and the corrective coefficient for the stress intensity factor was introduced. Fatigue tests with a loading frequency of f = 100 Hz were carried out on cylindrical specimens with constant amplitude of the cyclic load which is a proportion of the compressive load at failure ( F) obtained from the uni-axial compression tests. The fatigue property of the specimens was analysed and the relationship ( S − lg N) between the maximum stress and the number of loading cycles at failure for specimens with pre-existing flaws was proposed. The effect of pre-existing flaws on the fatigue life ( N) and dynamic load ( S) which can be applied was investigated. [ABSTRACT FROM AUTHOR]

Cairo City has a large number and different forms of Islamic archaeological sites, in particular, at El-Gammalia and El-Moez streets, as well as Coptic archaeological sites, e.g. at Mari Gergis. Human interference and activities at these historical areas resulted in flooding such sites’ foundations with domestic water, deteriorating its basal courses by salt weathering. The 1992 earthquake is another natural environmental hazard severely affecting many of these sites. The aim of the current study is to examine some factors (of bedrock and buildings) that are expected to control building susceptibility to damage by earthquakes by taking 38 Islamic archaeological sites in the El-Gammalia area as a representative case study. Detailed field recordings of site damage category before and after the quake and continued recording of damage features generated by the 1992 quake over the last 14 years, measuring depth to sub-surface water, measuring buildings’ height before the quake and bedrock sampling at these sites for geotechnical investigations were all considered for achieving this aim. The data has been processed mathematically and graphically (using the Excel package) to examine the main factors responsible for building susceptibility to damage by earthquakes. The selected archaeological sites give an excellent representation of the factors controlling building susceptibility to damage by quakes; it is found that the sites with heights (before the quake) ranging from 12 to 14 m are the most affected ones; the sites with the highest damage category before the quake were more susceptible to more damage by the quake; the sites that had been built on alluvium soil were more affected than those built on the Eocene limestone. The age of these sites has, to a small extent, indirect control on sites’ susceptibility to damage by the quake, particularly in parts flooded with domestic water (i.e. affected by salt weathering). The depth to sub-surface water is an effective parameter on sites’ basal courses (through salt weathering), which, indirectly, control a building’s susceptibility to quakes, particularly where the depth of water ranges from 0.6 to 1.6 m in alluvium bedrock. The alluvium soil at the study area has a liquid limit ranging from 62% to 82%, plastic limit from 37% to 86% and plasticity index from 26% to 46% and free swelling from 27% to 81%. These geotechnical limits for such alluvium bedrock indicate that its clay minerals are mostly montmorrillonite. [ABSTRACT FROM AUTHOR]

We investigate the conditions under which an optical system (or device) may transform polarization states at its input into orthogonal states at its output. We find that such polarization orthogonalization is possible if the Jones matrix of the optical system satisfies a specific inequality. One, two, or an infinite number of input polarization states may be orthogonalized. In the latter case, the locus of input states is a circle in the complex plane (and on the Poincaré sphere) of polarization. Several examples are given for illustration. [ABSTRACT FROM AUTHOR]

After introducing the new linear strain sensors and the theory behind their modus operandi, the paper discusses in general the performance characteristics as well as the potential value of their application in geomechanics. Application features and effects of application environments are then outlined and examples of practical applications are given. [ABSTRACT FROM AUTHOR]

The modified borehole jacking method, as introduced by De La Cruz in 1978, has important theoretical advantages over the common method which is associated with the name Goodman. So far, however, the modified method has not succeeded, mainly due to a lack of suitable instrumentation. To overcome this problem, a new type of modified borehole jack has been designed, built and tested. The new jack incorporates two highly innovative components: a recoverable sensor for measuring tangential strain at borehole surfaces and stacked hydraulic cylinders for extra-high load outputs. The new jack has been developed to the point at which its technical feasibility under field conditions, including its capability of yielding meaningful results, is demonstrated. Calibration in a hollow steel cylinder revealed that the new modified jack yields the correct Young's modulus within an error margin of less than ±5%. In-situ jacking tests were carried out at a major dam construction site. Results were obtained from both common and modified borehole jacking and from conventional laboratory testing of drill cores. The results of these tests are presented and discussed against the background of the particular rock conditions at the site. [ABSTRACT FROM AUTHOR]

The intensity transmittance α of a linear nondepolarizing optical system is investigated as a function of the state of polarization of the incident light. For totally polarized incident light the state of polarization is completely described by a single complex variable χ. In the χ-plane, the loci of incident polarizations that experience equal attenuation or amplification [α(χ)=constant] upon passing through the system constitute a family of nonintersecting coaxal circles. The zero-radius point circles of the coaxal family represent two orthogonal polarizations χ and χ that pass through the system with maximum and minimum transmittances, respectively. Simple elegant expressions are derived for α in terms of the properties χ , χ ; α and α of the system. When χ is expressed in terms of the azimuth and the ellipticity of the polarization ellipse a generalized version of Malus' law is obtained which is applicable to any optical system. Special cases of optical systems are discussed. The condition that a Jones matrix represents an active system is derived. Such a system may amplify polarization states inside a circular domain in the complex χ-plane and attenuate all other states. The results for totally polarized incident light are used to derive the polarization-dependent intensity transmittance of the system for unpolarized and partially polarized incident light. A new set of three parameters is introduced to describe the state of polarization of partially polarized light. The polarization-dependent intensity transmittance is completely determined by four real quantities which can be measured photo-ellipsometrically. [ABSTRACT FROM AUTHOR]

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A new angle of incidence of significance, when considering the reflection of electromagnetic waves at interfaces between transparent media, is defined. At this angle, denoted by φ, the reflection coefficient of parallel-polarized radiation is equal in magnitude and opposite in sign to the reflection coefficient at normal incidence. No similar angle exists for the perpendicular polarization. If ε is the relative dielectric constant, i.e., the ratio of the dielectric constant of the medium of refraction to that of the medium of incidence, we find that tan φ=(ε+ε). Measurement of φ, by equalization of the absolute (intensity) reflectances at normal and oblique incidence, allows ε to be determined using the inverse relation ε=(tanφ+1/4)−1/2. [ABSTRACT FROM AUTHOR]

Properties of the complex-plane representation of polarization are derived which include first the resolution of an arbitrary polarization into two orthogonal states, and secondly the definition of nearness functions that express the closeness of the polarization states represented by two points in the complex plane. Applications where these results are significant are discussed. [ABSTRACT FROM AUTHOR]