The evolution of the natural and pristine Mediterranean coastline Port aux Princes-Sidi Daoued(Gulf of Tunis,NE-Tunisia) is studied during the period of 1887–2010 on the basis of an ancient minute of bathymetry(1887)...The evolution of the natural and pristine Mediterranean coastline Port aux Princes-Sidi Daoued(Gulf of Tunis,NE-Tunisia) is studied during the period of 1887–2010 on the basis of an ancient minute of bathymetry(1887) and aerial photographs treated by numerical photogrammetric methods. Morphological changes of the coastline shows a general retreat despite the absence of the various anthropogenic actions. Adding to the drift currents and the currents of high energy that are generated by the N-W dominant waves along steeply sub-marine funds, the erosion is mainly due to the sea level rise which increased since the beginning of the 2000 s. The Port aux PrincesSidi Daoued coastline works as a single littoral cell limited by Jbel Korbous to the SW and the fishing harbor of Sidi Daoued to the N-E.展开更多
In this study, the reproduction of the sand smelt, Atherina lagunae, from the Tunis North Lake is investigated. The smallest mature female was 39 mm total length (TL). Fifty percent of the females were mature at 58 mm...In this study, the reproduction of the sand smelt, Atherina lagunae, from the Tunis North Lake is investigated. The smallest mature female was 39 mm total length (TL). Fifty percent of the females were mature at 58 mm (TL). The yearly and monthly average gonadosomatic indexes (GSI) are presented. The average value of GSI for the 12-month period was respectively 3.02%, 2.57% and 2.8% for females, males and both sexes. The GSI began to increase in March (2.37% for females and 2.12% for males). The maximum GSI was recorded in May, 11.29% for females and 10.03% for males. The highest values were recorded between March and July, indicating the reproduction period of Atherina lagunae in the Tunis North Lake. Similar GSI values were recorded in sand smelt males from brackish lagoons of southern France.展开更多
In this study, zinc (Zn), cadmium (Cd), lead (Pb), phosphorus (P) and calcium (Ca) concentrations in mus-cles, gills, liver, gonads and skeletons of two natural populations of sand smelt Atherina lagunae (Teleostean, ...In this study, zinc (Zn), cadmium (Cd), lead (Pb), phosphorus (P) and calcium (Ca) concentrations in mus-cles, gills, liver, gonads and skeletons of two natural populations of sand smelt Atherina lagunae (Teleostean, Atherinidae) normal and deformed, as well as bioaccumulation of these elements from the water and the sediment in the North Tunis Lake were investigated. The analysis of Ca was performed with flame atomic absorption spectrometry. The average concentrations of Ca in the different tissues analyzed show higher val-ues in healthy atherines except in gonads where the average concentration of Ca in deformed atherines sig-nificantly exceeds that in normal atherines (p < 0.05) and the spine Ca concentrations were similar in the two populations. Zinc, cadmium, lead and phosphorus were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The Zn concentrations of Atherina lagunae in North Tunis Lake were very high compared to other studies in other lagoons. The highest concentrations were found in deformed atherines. The differences are significant for all tissues studied (p < 0.05). The average concentration of P in different tissues analyzed shows that the highest values were detected in the normal population of Atherina lagunae. The potential rate of Cd was below the detection limit in the different organs analyzed, in water and sediment.展开更多
<span style="font-family:Verdana;">The determination of geoid models with great precision (centimeter) was always at the center of interest in geodesy research [<a href="#ref1">1</a&...<span style="font-family:Verdana;">The determination of geoid models with great precision (centimeter) was always at the center of interest in geodesy research [<a href="#ref1">1</a>] [<a href="#ref2">2</a>]. One of the most used methods to calculate the geoid model is the method called Remove-Compute-Restore (R-C-R). This method applies the stokes’ integral formula by the use of short, medium and long wavelength information via the three main stages R-C-R. The GravSoft software implemented by [<a href="#ref3">3</a>] was used for this study. Geodetic heights, a digital terrain model (SRTM) and leveled GPS points were used as inputs. The geoid modeling was carried out on the North region of Tunisia (Grand Tunis and Bizerte) on an area of 83 × 83 km. The accuracy of the quasi-geoid provisional reached 3.1 cm.</span>展开更多
Several factors overlap in making urban heritage conservation vulnerable in terms of long-term sustainability.The purpose of this study is to offer insights into the dynamic role that heritage governance plays in the ...Several factors overlap in making urban heritage conservation vulnerable in terms of long-term sustainability.The purpose of this study is to offer insights into the dynamic role that heritage governance plays in the current sustainability debate.This purpose is achieved by investigating the shift from a‘governing for culture’approach to a‘governing through culture’approach in heritage conservation.Subsequently,a case is built for a circularity-based conservation strategy applicable to the governance of historic cities.Different indicators of the circular governance approach are considered,and useful data are collected in comparative form.The cross-matching relationship between the factors is then evaluated by employing the analytic hierarchy process(AHP)on the collected data.As a test case,the conservation strategy of the Medina of Tunis is presented.For a more general conservation model,case-specific data are acquired.Finally,the same framework is applied to compare the case-dependent and case-independent data to define an integrated conservation framework.The obtained results show that the knowledge and data exchange factor,carries the highest significance.This result translates into heritage-led urban regeneration through knowledge sharing and the effective redistribution of cultural activities in historic city centres.展开更多
A theoretical and modulation study of a dipole antenna located in rectangular waveguide is presented. The aim is to determine the nature and dimensions which allow us to attain the simulations in free space. We compar...A theoretical and modulation study of a dipole antenna located in rectangular waveguide is presented. The aim is to determine the nature and dimensions which allow us to attain the simulations in free space. We compare the behavior of a dipole antenna modeled by MOM-GEC with those obtained in free space. A method of moment (MoM) approach combined to the generalized equivalent circuit (GEC) modeling is applied to compute the input impedance of a dipole antenna resonating at 1.8 GHz. A parametric study is conducted to investigate the wall effects on the antenna performances. Also we study the convergence of the input impedance as a function of test function number. The current values with integral method (MOM) are compared with the computed values obtained from numerical methods such as the combined MOM-GEC. The simulated values agree with values obtained from numerical methods.展开更多
文摘The evolution of the natural and pristine Mediterranean coastline Port aux Princes-Sidi Daoued(Gulf of Tunis,NE-Tunisia) is studied during the period of 1887–2010 on the basis of an ancient minute of bathymetry(1887) and aerial photographs treated by numerical photogrammetric methods. Morphological changes of the coastline shows a general retreat despite the absence of the various anthropogenic actions. Adding to the drift currents and the currents of high energy that are generated by the N-W dominant waves along steeply sub-marine funds, the erosion is mainly due to the sea level rise which increased since the beginning of the 2000 s. The Port aux PrincesSidi Daoued coastline works as a single littoral cell limited by Jbel Korbous to the SW and the fishing harbor of Sidi Daoued to the N-E.
文摘In this study, the reproduction of the sand smelt, Atherina lagunae, from the Tunis North Lake is investigated. The smallest mature female was 39 mm total length (TL). Fifty percent of the females were mature at 58 mm (TL). The yearly and monthly average gonadosomatic indexes (GSI) are presented. The average value of GSI for the 12-month period was respectively 3.02%, 2.57% and 2.8% for females, males and both sexes. The GSI began to increase in March (2.37% for females and 2.12% for males). The maximum GSI was recorded in May, 11.29% for females and 10.03% for males. The highest values were recorded between March and July, indicating the reproduction period of Atherina lagunae in the Tunis North Lake. Similar GSI values were recorded in sand smelt males from brackish lagoons of southern France.
文摘In this study, zinc (Zn), cadmium (Cd), lead (Pb), phosphorus (P) and calcium (Ca) concentrations in mus-cles, gills, liver, gonads and skeletons of two natural populations of sand smelt Atherina lagunae (Teleostean, Atherinidae) normal and deformed, as well as bioaccumulation of these elements from the water and the sediment in the North Tunis Lake were investigated. The analysis of Ca was performed with flame atomic absorption spectrometry. The average concentrations of Ca in the different tissues analyzed show higher val-ues in healthy atherines except in gonads where the average concentration of Ca in deformed atherines sig-nificantly exceeds that in normal atherines (p < 0.05) and the spine Ca concentrations were similar in the two populations. Zinc, cadmium, lead and phosphorus were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The Zn concentrations of Atherina lagunae in North Tunis Lake were very high compared to other studies in other lagoons. The highest concentrations were found in deformed atherines. The differences are significant for all tissues studied (p < 0.05). The average concentration of P in different tissues analyzed shows that the highest values were detected in the normal population of Atherina lagunae. The potential rate of Cd was below the detection limit in the different organs analyzed, in water and sediment.
文摘<span style="font-family:Verdana;">The determination of geoid models with great precision (centimeter) was always at the center of interest in geodesy research [<a href="#ref1">1</a>] [<a href="#ref2">2</a>]. One of the most used methods to calculate the geoid model is the method called Remove-Compute-Restore (R-C-R). This method applies the stokes’ integral formula by the use of short, medium and long wavelength information via the three main stages R-C-R. The GravSoft software implemented by [<a href="#ref3">3</a>] was used for this study. Geodetic heights, a digital terrain model (SRTM) and leveled GPS points were used as inputs. The geoid modeling was carried out on the North region of Tunisia (Grand Tunis and Bizerte) on an area of 83 × 83 km. The accuracy of the quasi-geoid provisional reached 3.1 cm.</span>
文摘Several factors overlap in making urban heritage conservation vulnerable in terms of long-term sustainability.The purpose of this study is to offer insights into the dynamic role that heritage governance plays in the current sustainability debate.This purpose is achieved by investigating the shift from a‘governing for culture’approach to a‘governing through culture’approach in heritage conservation.Subsequently,a case is built for a circularity-based conservation strategy applicable to the governance of historic cities.Different indicators of the circular governance approach are considered,and useful data are collected in comparative form.The cross-matching relationship between the factors is then evaluated by employing the analytic hierarchy process(AHP)on the collected data.As a test case,the conservation strategy of the Medina of Tunis is presented.For a more general conservation model,case-specific data are acquired.Finally,the same framework is applied to compare the case-dependent and case-independent data to define an integrated conservation framework.The obtained results show that the knowledge and data exchange factor,carries the highest significance.This result translates into heritage-led urban regeneration through knowledge sharing and the effective redistribution of cultural activities in historic city centres.
文摘A theoretical and modulation study of a dipole antenna located in rectangular waveguide is presented. The aim is to determine the nature and dimensions which allow us to attain the simulations in free space. We compare the behavior of a dipole antenna modeled by MOM-GEC with those obtained in free space. A method of moment (MoM) approach combined to the generalized equivalent circuit (GEC) modeling is applied to compute the input impedance of a dipole antenna resonating at 1.8 GHz. A parametric study is conducted to investigate the wall effects on the antenna performances. Also we study the convergence of the input impedance as a function of test function number. The current values with integral method (MOM) are compared with the computed values obtained from numerical methods such as the combined MOM-GEC. The simulated values agree with values obtained from numerical methods.
