Near-surface imaging of a buried foundation in the Western Desert,Egypt, using space-borne and ground penetrating radar

ALOS/PALSAR L-band full polarimetric data have been used to detect and characterize a well-defined geometric target hidden under sand deposits in the Western Desert of Egypt. This buried object is rectangular in shape with very straight boundaries and encloses an area of 500 m². Inside the rectangular area there is a perfectly circular feature of approximately 53 m² area. High and medium resolution optical satellite images (WorldView-2, ALOS/AVNIR-2) and field investigation confirm that the topography of the study area is relatively flat and completely covered by dry sand. The electromagnetic wave scattering behavior of the detected buried object was measured by decomposing the scattering matrix of ALOS/PALSAR full polarimetric data into Entropy-Alpha (H/α) and Freeman and Durden decompositions. Furthermore, a combination of unsupervised classification algorithms and Constant False-Alarm Rate (CFAR) edge detection was performed on the polarimetric data which revealed a well-defined geometric shape with straight borders. These borders have high α angles with low entropy, which physically means double bounce scattering mechanism with low randomness and is very similar to that of an urban scatterer, indicating that the detected target might be a buried wall-like foundation of a man-made structure. Moreover, 28 ground penetrating radar (GPR) profiles were acquired using a 270 MHz shielded antenna to validate the satellite radar remote sensing results. The GPR profiles reveal very clear hyperbolic shapes at 1.5 m depth with one of them showing a large hyperbolic shape-like structure, which might indicate the presence of a buried foundation. Thus the site might have significance to archaeological studies of the Western Desert, particularly previous human occupation and the sources of water for such habitation.     

Evaluation of the Nonlinear Seismic Response of an Earth Dam: Nonparametric System Identification

A system identification framework is proposed to investigate the nonlinear dynamic response of massive earth dams using the seismic motion recorded by a sparse array of accelerometers. The framework includes a methodical step of nonparametric analyses to characterize the involved loading conditions and response mechanisms. This nonparametric step provides essential information to reduce the indeterminacy of the associated parametric identificatin problem and ensure a proper model selection, calibration, and validation. The proposed framework was applied to the Long Valley earth dam (California) and benchmarked using records of a series of 1980 earthquakes. This article presents the conducted correlation, spectral motion reconstruction, and nonparametric stress-strain analyses. These analyses revealed a complex three-dimensional dynamic response marked by non uniform boundary conditions and a shear stress-strain behavior slightly less nonlinear than what was observed in triaxial tests of soil samples taken from the dam core.     

Climatic signal in tree-ring chronologies of Cedrus deodara from Chitral Hindukush Range of Pakistan

Tree-rings are an important tool for the investigation of paleoclimatic records for regions or periods of time with no instrumental climatic data. However, the responses of different species and sites to various climatic parameters are unusual. In the present study, we developed tree-ring-width chronologies of Cedrus deodara from three different sites of Chitral Hindukush range of Pakistan. The study was conducted to understand tree-growth climate relationship and its applicability in proxy climate investigations. The chronologies covered the past 469 to 595 years, with a mean segment length (MSL) ranging from 148 to 223 years. Climatic data obtained from the three weather stations showed strong correlation and was found useful for tree-ring climate relationships. Correlation Function (CF) and Response Function (RF) analysis showed that spring precipitation (March–May) is a critical limiting factor for tree-ring growth, and temperature prior to November may also play a major role in affecting tree ring-growth. The results exposed that the three sites have continuous relationship indicated that only single species from different locations are affected by the same environmental variables and hence can be used in climate reconstruction in combination. The Cedrus deodara chronologies developed at different locations had several corresponding narrow and wide marker rings indicating a large macroclimatic response to regional climatic conditions. The current study suggests that the tree-rings of Cedrus deodara from the Chitral Hindukush range could be used to develop chronologies for the reconstruction of seasonal climatic variables.     

It’s hard to be down when you’re up: interpreting cultural heritage through alternative media

Heritage places are characteristically imbued with a multiplicity of meanings contingent on the specificities of the society, time and space in which such places are perceived. The interpretation of places also depends on the affordances of the representational medium through which these places are perceived and the ways in which such a medium is socially deployed and interpreted. Using the ancient settlement of Sirkap, located in modern-day Pakistan, as a case study, the present article demonstrates that a change in the representational medium entails a change in the interpretation of archaeological records. Most conventional historical accounts of Sirkap use two-dimensional site maps and city plans as the primary media to represent the urban fabric of the ancient settlement. These media lend themselves to interpreting the Block D Apsidal Temple complex as the dominant socio-religious structure in the affluent northern parts of the settlement. When the authors developed an interactive three-dimensional reconstruction of Sirkap using gaming technology – a medium that allows users, through their avatars, to explore the settlement from the standpoint of a pedestrian – it was immediately obvious that the aforementioned Block D Apsidal Temple complex did not demand such an interpretation. Instead, the authors argue that, at least in the affluent northern parts of the settlement, the northern gate, its adjacent fortifications, and the Block A stupa court were the dominant structures. Such an interpretation leads the authors to question the canonical understanding of the role of the state and its military apparatus in the socio-religious life of Sirkap.     

The Development Impact of NGO Activities in the Red Sea Province of Sudan: A Critique

This article examines the results of, and the prospects for, the declared shift of NGOs from relief operations to development activities in the Red Sea Province of eastern Sudan. Statistical and qualitative information contained in the reports of NGOs themselves provides the main data source on which the analysis is based. Although NGOs have been successful in conducting massive relief operations in the area, the article asserts that they have not yet and are not expected to achieve any tangible results on the development front. The main reason for this is the apparent misconception of development on the part of the NGOs as an isolated, localized activity which they can perform; another is the NGOs' failure to recognize the difference in the methods, means and prerequisites necessary for relief and for development; a third is the failure of NGOs to equip local institutions to absorb and/or sustain any achieved ‘development’, since most NGOs operate in complete isolation from governmental and traditional Beja institutions.     

The Arab Uprisings and the United States: The Dichotomy Between Balancing Stability and Upholding Commitment to Democracy

The Arab Spring, a revolutionary movement for democracy that swept across the Arab Middle East in 2010, has contributed to the downfall of several oppressive authoritarian regimes in Tunisia, Egypt, Libya, and Yemen. The movement represented several uprisings that placed the United States in a precarious position. While the uprisings have shaken U.S. policy to the core, they also presented a historic opportunity for American policymakers to craft a new and comprehensive policy that is compatible with the much‐coveted principles of democracy, freedom, and justice in a region that has historically been unable to grasp such principles. This article argues that the American administration under President Barak Obama squandered this opportunity by pursuing an incoherent and inconsistent policy. This policy revealed Obama's support of the uprisings calls for political reforms that aligned with American liberal values. However, the policy also reflected a commitment to ensure security and stability by maintaining autocratic regimes the protesters hoped to overthrow. This article demonstrates that the policy lacked consistency and clarity as it shifted from one uprising to another.