Perspectives on the contribution of Arabs and Muslims to geography     

El-Sayed El-Bushra  M. M. Muhammadain 《GeoJournal》1992,26(2):157-166

Conclusion The fact that Arab and Muslim geographers had contributed in a substantial way to geographical thought is well-recognized by many scholars of international standing including orientalists. It has now also been proved beyond any doubt that Muslim geographic thought was transmitted through Spain (Andalusia), Italy and Sicily during the Middle Ages to Europe. The Muslims had more advanced culture than did most of medieval Europe, and had made great discoveries in various fields of study (Hasan 1967). They had also preserved many of the writings of ancient Greek, Roman and other oriental civilizations. It was through Spain that the Muslims made these works as well as their own contribution available for European scholars. The centres of learning in Muslim Spain were thriving, with scholars from many places and particularly so from Europe. As Arabic was the language of culture and learning, many books were translated from Arabic into Latin and other European languages including German, French and English (Ahmed 1947; Hasan 1967; Kish 1978; James & Martin 1981; Muhammadain 1988).It is also understood that when geographical works were not translated some of the ideas and concepts revealed in them were adopted in other translated works. With the final collapse of Muslim rule in Spain (1492 AD), Muslim intellectual centres were opened to Christians from all over Europe. Indeed, translations from Arabic into European languages continued well into the 16th century, and some of the translated books remained in use until the 17th century.To ignore, as did some writers, the contribution of Muslims to geography during the Middle Ages, and to claim that the European Renaissance developed independently of what was happening in the Islamic world, is to dismiss seven centuries of Muslim leadership of world culture. Surely, no one nation or group of people can claim all the achievements of our present civilization. Present-day civilization is actually the sum total of all the past human efforts which have been accumulated over the long years of man's existence on earth, and as such there can be no gaps in human cultural history. While accepting the fact that the contribution of the various groups of people to the advancement of culture has not been the same, all are participants and have shared in its building and development. By looking at human cultural history in this spirit, it would not be difficult to appreciate the positive role played by the Arabs and Muslims in the advancement of knowledge during the Middle Ages. One of these branches of knowledge, which we have been trying to explain in this essay, is geography. To put the contribution of Arab and Muslim geographers into even more perspective, one can say that their most outstanding and original contributions, as has been stated before, were in the field of regional and mathematical geography as well as surveying. Although most of the studies were concerned with regions or individual countries, some contributions were highly specialized dealing with only one topic, such as climate or plants. The regional approach is represented by the many books written with the title: Al-Masalik wa Al-Mamalik or Roads and Provinces, and those with the title: Al-Bilad or Countries. As has been indicated earlier in this essay, treatment in these regional studies has beencomprehensive covering almost all aspects of physical and human geography.To contemporary Muslim people the science of geography will continue to be as appealing as it was to their predecessors, partly because of religious needs and partly because of the Muslim love for his environment. To sum up, in the following quotations from the Holy Quran Muslims are asked to contemplate four things: qu]Do they not look At the Camels, How they are made? And at the sky, How it is raised high? And at the mountains, How they are fixed firm? And at the Earth, How it is spread out? (Holy Quran: Sura LXXXVIII, verses 17\2–20).The contemplation of these things does not only make Muslims sense the absolute powers of their Creator, but also makes them constantly aware of their geographical surroundings.  相似文献   

Alternative method to solve soliton envelope equation     

D. K. Callebaut  M. F. El-Sayed 《Astrophysics and Space Science》1994,222(1-2):237-240

In studying the nonlinear electrohydrodynamic stability of solitary wave packets of capillary-gravity waves, in (2+1) dimensions, for dielectric fluids, we found that the complex amplitude of the surface elevation can be described by a nonlinear Schrödinger equation which can be written in the form of a soliton envelope equation. Using the tanh method we get in a very simple way the solitary wave solutions of this equation which we had obtained before by using the Jacobian elliptic functions.  相似文献   

Trigonometric series representations of the orbital inclination function     

Mervat El-Sayed Awad 《Astrophysics and Space Science》1986,125(2):243-258

In this paper, new trigonometric series representations of the orbital inclination functionF _imp (i) in multiples of cosines or sines will be established for all possible values ofl, m, andp. For such representations, the literal analytical expressions and the recurrence formulae satisfied by their coefficients will be established. Moreover, an economic algorithm for the table formulation of these coefficients for the possible values ofl, m, andp is given. Finally, numerical examples of the representations forl=2(1)4;m=0(1)l;p=0(1)l are also included.  相似文献   

A new least-squares minimization approach to depth and shape determination from magnetic data     

El-Sayed M. Abdelrahman  Eid. R. Abo-Ezz  Khalid S. Essa  T.M. El-Araby  Khaled S. Soliman 《Geophysical Prospecting》2007,55(3):433-446

We have developed a least‐squares minimization approach to depth determination using numerical second horizontal derivative anomalies obtained from magnetic data with filters of successive window lengths (graticule spacings). The problem of depth determination from second‐derivative magnetic anomalies has been transformed into finding a solution to a non‐linear equation of the form, f(z) = 0. Formulae have been derived for a sphere, a horizontal cylinder, a dike and a geological contact. Procedures are also formulated to estimate the magnetic angle and the amplitude coefficient. We have also developed a simple method to define simultaneously the shape (shape factor) and the depth of a buried structure from magnetic data. The method is based on computing the variance of depths determined from all second‐derivative anomaly profiles using the above method. The variance is considered a criterion for determining the correct shape and depth of the buried structure. When the correct shape factor is used, the variance of depths is less than the variances computed using incorrect shape factors. The method is applied to synthetic data with and without random errors, complicated regionals, and interference from neighbouring magnetic rocks. Finally, the method is tested on a field example from India. In all the cases examined, the depth and the shape parameters are found to be in good agreement with the actual parameters.  相似文献