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31.
Leila M. Harris   《Geoforum》2008,39(5):1698-1708
This paper advances recent conversations related to the need to better engage postcolonial scholarship in development geography. To do so, I bring together analytics offered by postdevelopmental, feminist geographic, and postcolonial scholarship to analyze contemporary development efforts in southeastern Turkey. To provide necessary background for the case study context, the paper considers three key moments foundational for Turkish modernist development aspirations: the foundations of the Republic through Kemalism, the emergence of Kurdish separatism and PKK resistance, and Turkish efforts to gain entry to the EU. Reading these moments, and their culmination in contemporary development efforts focused on the southeastern Anatolia region, through postdevelopmental and feminist geographic literatures invites a reading that highlights socio-spatial difference as underwriting modernist development interventions in this region. Drawing on postcolonial scholarship, particularly Bhabha’s notion of ambivalence, further enables a reading of socio-spatial difference as also undermining Turkish modernist development, signaling precisely the points where the project comes undone. The example thus lends endorsement to the need for enriched engagement between postcolonial theory, feminist and development discussions in geography, suggesting that postcolonial concepts might enable clearer focus on the ambiguities, tensions, and contradictions inherent to development geographies.  相似文献   
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The main goal of the proposed work is to delineate structural boundaries in a very complex geology environment using the spatial and statistical properties of the potential field data. The analysis is performed using magnetic anomaly of the total field data over In Ouzzal, an Archaean north–south elongated block belonging to the Hoggar (Algeria). This region is geologically and geophysically very poorly known except some localized areas. The intrinsic properties of high-frequency signals and the related causative sources are explored, thanks to two-dimensional continuous wavelet transform. The obtained results, represented by spatial distribution of the maxima of the modulus of the wavelet transform at each scale, clearly show that the major magnetic singularities of the field may be related to geological features. Comparison with the Euler’s deconvolution solutions exhibits a very good correlation. Even though where geological structures are known, our method shows better resolution and accuracy. The proposed multiscale method proves to be more powerful, easy to use, and versatile where classical methods of potential field interpretation fail or are very constraining. However, work is still ongoing to try to better and fully characterize the causative sources of the potential fields.  相似文献   
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The goal of this paper is to document causes of the failure of stabilization measures undertaken for stabilizing a complex landslide threatening the Sidi Rached viaduct in Constantine, Algeria. Since the first instabilities, documented in 1910 during its construction, significant disturbances have been regularly observed on its eastern part and reinforcements carried out were only temporarily effective. Observed disturbances are inherently related to the fact that the eastern abutment and the three subsequent piers are built on unstable Maastrichtian marls whereas the remainder of the viaduct rests on stable Turonian limestone. The five main factors controlling the activation of the failure process are reviewed: (1) geomorphology, (2) geology, (3) human activities, (4) climate, and (5) seismicity. Data interpretation of two inclinometer surveys carried out close to the eastern abutment shows that the unstable mass moves westward, towards the Rhumel gorges. The main slip surface is located in the Maastrichtian schistose marl, at a depth ranging from about 8 m (west) to about 30 m (east). This translational slide is associated with a settling phenomenon due to the petrophysical properties of the unstable marl.  相似文献   
36.
The response surface methodology involving the five‐level central composite design (CCD) was employed to model and optimize the Cr(VI) immobilization process in a Cr‐spiked soil using starch‐stabilized zerovalent iron nanoparticles (ZVIn). ZVIn were synthesized via a borohydride reduction method and characterized by X‐ray diffraction (XRD) and scanning electron microscopy (SEM). All Cr(VI) immobilization experiments were conducted in a batch system. The variables for the CCD optimization were the ZVIn dosage (% w/w), reaction time (min), and initial Cr(VI) concentration in soil (mg/kg). The predicted response values by the second‐order polynomial model were found to be in good agreement with experimental values (R2 = 0.968 and adj‐R2 = 0.940). The optimization result showed that the Cr(VI) immobilization efficiency presented the maximal result (90.63%) at the following optimal conditions: ZVIn dosage of 1.5% w/w, reaction time of 60 min, and an initial Cr(VI) concentration of 400 mg/kg.  相似文献   
37.
The knowledge of the climatic behavior especially that one of semi-arid regions is required to optimize the management of water resources. Here climate variability is directly related to water resources that are of a high socio-economic and environmental significance. This work deals mainly with a statistical analysis of the precipitation regime to assess its spatial distribution and temporal variation in north-western Algeria. For this, a time series and a principal component analysis are performed on rainfall series representing annual precipitations of twenty-one meteorological stations for the period 1914 to 2004, the most complete and longest of West Algeria, in order to detect patterns and trends in the region. A spectral analysis of the time series revealed the existence of a period of roughly 30 years for all stations. Furthermore, the trend of a wide part of the obtained spectra suggests the existence of another period longer than the samples size.  相似文献   
38.
In this paper, we have analyzed the geomagnetic anomaly field reduced to the pole by the 2D directional continuous wavelet transform (DCWT). The objective is to identify geological contacts. The proposed idea has been applied firstly at a synthetic model, the obtained results showed the robustness of the proposed technique, after that the synthetic data has been noised; analysis shows that contacts identified by DCWT are affected by noise. To resolve this problem, we have proposed an algorithm to reduce the noise effect in the contacts model. Application on the real geomagnetic data of In Ouzzal area located in the West of Hoggar (Algeria) shows clearly the robustness of the proposed method. Comparison with the analytic signal solutions exhibits a difference between the two models of contacts. Our method gives results that are accurate with the structural geological map.  相似文献   
39.
Inadequate moisture supply is one of the important factors limiting crop yields in the world. Increasing the efficiency of moisture available has an important role on the crop-producing capacity of the soil. This paper presents the results of the laboratory experiments conducted to assess the influence of two mulches of windy sand and light expanded clay aggregate (LECA) with three thicknesses (1, 3, and 4 cm) on soil surface in soil columns. Loamy soil was taken from the experimental site in Bayaz of Rafsanjan (a city in Kerman province in Iran). These experiments were done as completely randomized design with two treatments of mulches (windy sand and LECA) and tree replicates. The results show that the columns of treated soil with mulches had lower evaporation as compared to the control. The rate of evaporation from the soil surface of columns was decreased with increasing the thickness from 1 to 4 cm of each of the two mulches. The LECA mulch was more effective in reducing evaporation from the soil surface than the windy sand mulch with the same thicknesses. The most effective among the thicknesses for mulches was 3 cm.  相似文献   
40.
The main goal of this paper is to design and develop a new technique and software tool that help automatic lithofacies segmentation from well logs data. Lithofacies is a crucial problem in reservoir characterization and our study intends to prove that techniques like wavelet transform modulus maxima lines (WTMM) and detrended fluctuation analysis (DFA) approaches allow geological lithology segmentation from well logs data. On the one hand, WTMM prove to be useful for delimitation of each layer. We based on its sensitivity on the presence of more than one texture. On the other hand, DFA is used to enhance the estimation of the roughness coefficient of each facies. We have used them jointly to segment the lithofacies of boreholes located in the Algerian Sahara. Obtained results are encouraging to publish this method because the principal benefit is economic.  相似文献   
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