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Abdel-Hamid A. Khedr 《International Journal of Salt Lake Research》1996,5(3):221-239
The macrophyte distribution of Lake Manzala is described in relation to water depth, salinity, dissolved oxygen, pH, Cl–, NO
3
–
and PO
4
3–
. Changes in species composition of macrophytes are visualised by means of multivariate analysis. The TWINSPAN classification and CANOCO ordination programs (DCA & CCA) were used to analyse the data set. The classification of 100 stands revealed 8 vegetation groups which indicated eleven dominant communities. These arePhragmites australis, Typha domingensis, Scirpus maritimus, Echinochloa stagnina and Ludwigia stolonifera as emergent hydrophytes;Eichhornia crassipes andAzolla filiculoides as floating hydrophytes. The dominant submerged hydrophytes arePotamogeton pectinatus, Najas armata, Ceratophyllum demersum andRuppia maritima. The northern part of the lake with low depth and relatively high salinity has low species diversity (mainly emergent species). Species diversity increases with decreasing salinity and increasing eutrophication near the mouths of the drains in the western and southern parts of the lake. The recent changes in species distribution can be attributed to the effects of salinity, water depth and drainage water. A checklist of macrophytes in the lake is appended. 相似文献
2.
Performance improvement of integrated Inertial Measurement Units (IMU) utilizing micro-electro-mechanical-sensors (MEMS) and
GPS is described in this paper. An offline pre-defined Fuzzy model is employed to improve the system performance. The Fuzzy
model is used to predict the position and velocity errors, which are the inputs to a Kalman Filter (KF) during GPS signal
outages. The proposed model has been verified on real MEMS inertial data collected in a land vehicle test. A number of 30-s
GPS outages were simulated during the data processing at different times and under different vehicle dynamics. Performance
of the suggested Fuzzy model was compared to that of the traditional KF particularly during the simulated GPS outages. The
test results indicate that the proposed Fuzzy model can efficiently compensate for GPS updates during short outages. 相似文献
3.
El-Haddad Bosy A. Youssef Ahmed M. Pourghasemi Hamid R. Pradhan Biswajeet El-Shater Abdel-Hamid El-Khashab Mohamed H. 《Natural Hazards》2021,105(1):83-114
Natural Hazards - Floods represent catastrophic environmental hazards that have a significant impact on the environment and human life and their activities. Environmental and water management in... 相似文献
4.
Analysis of fault system in the high-P/T type Sambagawa metamorphic rocks of central Shikoku, southwest Japan, shows that conjugate normal faults pervasively developed in the highest-grade biotite zone (upper structural level) in three study areas (Asemi river, Oriu and Niihama areas). These conjugate normal faults consist of NE–SW to E–W striking and moderately north-dipping (set A), and NNW–SSE striking and moderately east dipping (set B) faults. The fault set A is dominant compared to the fault set B, and hence most of deformation is accommodated by the fault set A, leading to non-coaxial deformation. The sense of shear is inferred to be a top-to-the-WNW to NNW, based on the orientations of striation or quartz slickenfibre and dominant north-side down normal displacement. These transport direction by normal faulting is significantly different from that at D1 penetrative ductile flow (i.e. top-to-the-W to WNW). It has also been found that these conjugate normal faults are openly folded during the D3 phase about the axes trending NW–SE to E–W and plunging west at low-angles or horizontally, indicating that normal faulting occurred at the D2 phase. D2 normal faults, along which actinolite breccia derived from serpentinite by metasomatism sometimes occurs, perhaps formed under subgreenschist conditions (ca. 250 °C) in relation to the final exhumation of Sambagawa metamorphic rocks into the upper crustal level. The pervasive development of D2 normal faults in the upper structural level suggests that the final exhumation of Sambagawa metamorphic rocks could be caused by “distributed extension and normal faulting (removal of overburden)” in the upper crust. 相似文献
5.
This paper presents an application of the neuro-fuzzy modeling to analyze the time series of solar activity, as measured through the relative Wolf number. The neuro-fuzzy structure is optimized based on the linear adapted genetic algorithm with controlling population size (LAGA-POP). Initially, the dimension of the time series characteristic attractor is obtained based on the smallest regularity criterion (RC) and the neuro-fuzzy model. Then the performance of the proposed approach, in forecasting yearly sunspot numbers, is favorably compared to that of other published methods. Finally, a comparison predictions for the remaining part of the 22nd and the whole 23rd cycle of the solar activity are presented. 相似文献
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