Descripción de España : (obra del siglo XII)

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201

Parameter Optimization In 3D Printer Recycle Machine

3D printing technology has evolved rapidly to becoming one of the most postulate method in manufacturing process. Commonly, standard manufacturing process which is subtractive that produces a lot of waste opposite to 3D printing technology is way friendly to the environment. The idea of this application additive manufacturing method in 3D printing leads to less or no wasted materials and consumption of plastic materials has significantly increased due to high demand in market. However, the plastic waste products from the 3D printing still undergo significant increase due to the problem in every human-made creation. In order to minimize the negative impact of plastic waste to the environment, a machine of recycle 3D printing has been made and study on parameter optimization on 3D printer recycle machine have been done. The study used Minitab software to analyze the factor of parameter of 3D printing recycle machine. Taguchi method was used to suggest some experiments to be performed and provides an optimal value for each parameter that needs to be optimized in the operation of extruding. Analysis of extruded filament was conducted for every 30cm with minimum of three repetitions. In comparison of the new extruding filament and original filament show that some minor difference of the mechanical properties by using tensile test method. Percentage of error for diameter of filament indicates that 1.77mm diameter with 1.14% as the lowest error while diameter of 1.82mm with 4.00% as the highest error. This shows that 3D printer recycle machine has been optimized with the percentage of error below than 5% and it could be further improved in order to help in minimizing the negative impact of plastic wastes to the environment

The Nile: its role in the fortunes and misfortunes of the Fatimid dynasty during its rule of Egypt (969-1171)

The epoch spanning the years 935-1094 constitutes - on the whole - the longest and driest period on record in the history of the Nile. A stretch of relatively normal discharge followed this phase, only for dryness to return. The reasons of this dry-wet-dry phenomenon have been recently appraised in the context of global climatic changes – the so-called “Medieval Warm Period” - that affected most of the known world between the 11th and the 13th centuries. It was in this period of Egyptian history that the Shi‘i Isma‘ili Fatimids replaced the Sunni Ikhshidids as rulers in 358/969 and, with alternating fortunes, continued to reign until 567/1171. In this paper, I examine how, faced with the convergence of extraordinary geo-climatic factors, the Fatimids managed (and mismanaged) the Nile and its valley. I contend that the imperial aspirations of the Fatimids in Cairo and beyond were in many ways subject to the typical unpredictability of the natural cycles of the river, hence the Fatimids’ success and failure in managing the varied economic, political and trading activities that took place along the Egyptian section of the Nile valley. A case in point highlighted here will be the Fatimids’ privileging of flax cultivation over wheat

Unconstrained Minimization Algorithms for Functions with Singular Or Ill-Conditioned Hessian.

The minimization of an unconstrained, real and twice differentiable function f:R('n) (--->) R is considered. Interest is focused on situations when the Hessian matrix of f(x) is either singular or ill-conditioned at or near the minimum. Two algorithms are presented for h and ling such problems. The first uses the pseudoinverse concept together with a finite scheme developed for computing the pseudoinverse or any square matrix. Convergence of the algorithm is proved, and some of its properties are also discussed. The second algorithm is based upon the transformation of the original minimization problem into one of finding the asymptotic solution of a related differential system. This leads to a "duality" between ill-conditioned minimization problems and stiff systems of ordinary differential equations. This duality is investigated and techniques for integrating stiff systems of ordinary differential equations are used for implementing a viable minimization algorithm. A study of the tradeoffs between speed and accuracy shows that stiff methods with only moderate levels of accuracy are required. This is an encouraging note since it eliminates the need for methods with high accuracy which tend to be computationally expensive due to the small stepsize that is often associated with them. Also since the Hessian matrix is real and symmetric, its eigenvalues are always real. Thus the stability problems, associated with the presence of some complex eigenvalues, do not exist here. This makes stiff integration schemes even more effective. Finally, a parameter identification problem, that is associated with an adaptive controller for the path control of surface ships in restricted waters, is solved using the two developed algorithms. Comparisons with the conjugate gradient method indicate the viability of the new algorithms.Ph.D.Industrial engineeringUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/158389/1/8125055.pd

[Mundus]

Faksimile, kopioitu valokuvasta. - Alkuperäinen kartta vuodelta 115

Fiqhu al Fitani

776 hal.; 24 cm

القص والاقتصاص بين قديم اللحظة وجديد التاريخ : قراءة في رواية ﻣﺘﻮﻥ ﺍﻷﻫﺮﺍﻡ ﻟﻠﻐﻴﻄﺎﻧﻲ / Narrating and Tracing the Past: A Reading of al-Ghitani\u27s Mutun al-ahram

[In keeping with al-Ghitani\u27s characteristic impulse toward autobiographical self-disclosure, early memory determines the orientation toward the Pyramids, always facing westward and straining for a clear vision, in his novel Mutun al-ahram (Pyramid Texts, 1994). This article seeks to explore the transhistorical and intertextual layering of word, vision, and personal destinies and ambitions, which constitute the creative principle at work in Ghitani\u27s Mutun and its sequel Sifr al-bunyan (1998). Just as personal memory figures in his two novels, so too does Ancient Egypt reveal itself, not in all the familiar trappings of its victory over time, but as a living legacy. What al-Ghitani understands as \u27living legacy,\u27 however, is the encrustation of a historical moment that survives time, whether in written accounts, in age-honored cultural practices or in monumental architecture. Al-Ghitani\u27s orientation is not exactly that of a reconstructive historian. Ancient Egypt becomes ultimately a trope for all that survives the forces of time and achieves monumentality. In Mutun al-Ahram, al-Ghitani follows in the footsteps of earlier figures, such as Abu Ja\u27far al-Idrisi and al-Maqrizi, and indeed all Arab scholars and historians until al-Tahtawi in the mid-nineteenth-century, by Arabizing and Islamizing the Pyramids, their history and their significance. / ‮تتناول هذه الدراﺳﺔ رواية متون الأهرام للغيطاني (٤٩٩١) بالتحليل في محاولة لتتبع أثر القديم، الذي هو قديم اللحظة، وﺍﻟﺘﻲ تأتي في شكل ذكرى شخصية مرتبطة بموضع بعينه، في جديد التاريخ٠ تخرج متون الأهرام في شكل عربي سليم وإن كان محتواها ينزع إلى رغبة المصري القديم في حفظ لحظته التاريخية ﺍﻟﺘﻲ هي أيضاﹰ قوام صوته المتفرّد وشخصيته ﺍﻟﺘﻲ عاش بها، وذلك بتسجيلها في حروف مقدسة تتغلب على تاريخية اللحظة بقوة اللغة ونموذجية تراكيبها وأساليبها الموروثة٠ يردُ الراوي في متون الأهرام بكل شخصية إلى الهرم حيث تمر بتجربتها الفريدة وتكتشف أويُتكشّف لها عن كنه غموض قدرها الذاتي، ثم هو يردّ بها إلينا، في شكل التأريخ أو أدب الحوليات وأنساق تراثية أخرى، وقد سجلها على بنية الهرم أو بنيانه والذي يشكل بدوره بنية الرواية٠ يتناول البحث بالتحليل بنية الرواية الشكلية ثم بنيتها الداخلية أو حركية السرد ثم نمطية الشخصية، ويختتم البحث بعرض لأساليب استيحاء مصادر الرواية ولنظرية الغيطاني حول الاستمرارية التاريخية، متطرقاﹰ إلى رواية لاحقة للغيطاني، سفر البنيان (٨٩٩١) التي تعبر روائياﹰ عن جماليات الفن المعماري الإسلامي٠‬