Modeling of high strength and wear resistance aluminum alloy based casting of composite material developed via conventional foundry method which is one of the most economical versatile and active research area and so for has not been thoroughly investigated. Due to complex nature of the composite materials and their related problems such as the nonlinear relationship between composition, processing parameters, heat treatment with the strength and abrasive wear, resistance can more efficiently be modeled by artificial neural networks. The artificial neural networks modeling requires sufficient data concerned with chemical composition , processing parameters and the resulting mechanical properties which were not available for such type of modeling. Therefore, a wide range of experimental work was conducted for the development of aluminum composites using conventional foundry method. Alloy containing Cu-Mg- Zn as matrix and reinforced with 1- 15 % Al 2 O 3 particles were prepared using stir casting method. The molten alloys composites were cast in metal mold. More than eighty standard samples were prepared for tensile tests and sixty samples were given solution treatment at 580 0 C for 1⁄2 hour and tempered at 120 0 C for 24 hours. Various characterization techniques apparatus such as X-ray Spectrometer, Scanning Electron Microscope, Optical Metallurgical Microscope, Universal Tensile Testing Machine, Vickers Hardness and Abrasive Wear Testing Machine were used to investigate the chemical composition, microstructural features, density, tensile strength, ductility (elongation), hardness and abrasive wear resistance. xixThese investigations including the material development and characterization were used for data generations as needed for modeling of high strength and abrasive wear résistance aluminum cast composites. For modeling purpose a multilayer perceptron (MLP) feedforward was developed and back propagation learning algorithm was used for training, testing and validation of the model. The modeling results shows that an architecture of 14 inputs with 9 hidden neurons and 4 outputs which include the tensile strength, elongation, hardness and abrasive wear resistance gives reasonably accurate results with an error within the range of 2-7 % in training, testing and validation. The modeling results shows that an alloy contents 2-3 % Cu, 2-3 % Mg, 3-5 % Zn reinforced with 10 % Al 2 O 3 can successfully be developed for highest strength (297 MPa) and highest abrasive wear résistance (0.4 gm weight loss /15 minutes using stir casting method. The modeling results also suggest that it is possible to develop the highest strength 466 MPa tensile strength and highest abrasive wear resistance aluminum alloy based casting composite materials having the matrix composition of 6 % Si, 2 % Mg with 3 % Zn reinforced with 2-5 % Al 2 O 3 particles.
لے ڈوبا مجھے میرا موبائل نحمدہ ونصلی علی رسولہ الکریم امّا بعد فاعوذ بااللہ من الشیطن الرجیم بسم اللہ الرحمن الرحیم معزز اسا تذہ کرام اور میرے ہم مکتب شاہینو!آج مجھے جس موضوع پر لب کشائی کا موقع دیا گیا ہے وہ ہے:’’لے ڈوبا مجھے میرا موبائل ‘‘ جنابِ صدر! سائنسی ایجادات نے تہلکہ مچا رکھا ہے، زندگی کو رنگینیاں عطا کی ہیں ، زندگی کو رعنائیاں نصیب ہوئی ہیں زندگی کے گلشن میں بہار آئی ہے، زندگی کے حسن میں نکھار آیا ہے، زندگی کے بادل گھٹابن کر برسے ہیں۔ صدرِذی وقار! زندگی نئے نہج پر رواں دواں ہے، گھر بیٹھے ہزاروں میل دور کے نظارے کر رہے ہیں ، فلک بوس چوٹیوں کے منظر دیکھ رہے ہیں، مہینوں کا کام گھنٹوں میں کر رہے ہیں ، کوسوں دور بیٹھے عزیز واقارب سے نہ صرف بات کررہے ہیں بلکہ ان کی تصویربھی دیکھ رہے ہیں۔ صدرِ ذی وقار! یہ سب کچھ سائنسی ایجادات کی بدولت ہے لیکن سہولتوں کے ساتھ ساتھ کچھ ایسی ایجادات بھی ہیں جس نے زندگی اجیرن کر رکھی ہے ، سکون برباد کر رکھا ہے، شرفاء کی کشتی بحر ذلت و رسوائی میں ٹامکٹوئیاں مارہی ہے، شرم و حیاء کا لباس اتر چکا ہے، سرکردہ لوگوں کی دستار کا طرہ نظر آنا بند ہو گیا ہے۔ جنابِ صدر! ان جدید ایجادات میں ایک ایجاد ایسی ہے جس کو موبائل کہتے ہیں، میں مانتا ہوں کہ یہ نفسہٖ بری نہیں ہے ، یہ بذاتِ خود غیر اہم نہ ہے، اس کی افادیت بھی مسلمہ ہے، اس کے فوائد بھی گوناگوں ہیں لیکن اس کے غلط استعمال نے اس کی افادیت کے ماہِ ضوفشاں کو گہنا دیا ہے۔ جنابِ صدر! موبائل آج ہر گھر میں ہے، ہرشخص کے پاس تقریباً موجود ہے، اس موبائل نے بجائے محبت و مودت...
Lexical investigation of words/selected passages of Quran is among many ways of exegesis of Quran. Such work is compiled on the basis of an extensive analysis of the text of the Quran and consideration of lexical examination of Quranic words. Specialized works on aspects of Quranic vocabulary has been in the tradition of Islamic scholarship right from the beginning and there are a number of works that help in the etymological & philological understanding of difficult words of Quran. The classic text by al-Raghib al-Isfahani named, Mufradat, is the best example of books that treat difficult words in the Quran. In this article, we have presented information regarding the works of scholars of Indian sub-Continent on the subject of Mufradat al-Quran (Selected passages of Quran). We have found that South Asian Scholars have written books abundantly in the field of Mufradaat and Luhgaat al Qur’an, in Arabic, English, Persian, Sindhi & Urdu languages. This study covers in detail an overview of the acclaimed works of subcontinent scholars which mainly split into precise and concise written books on the topic of Mufradat al Qur’an. Forty-eight books have been introduced in below pages. Our work is 1st step towards complete indexing of such works of Sub-continent scholars for easy access of scholars and researchers who want to do some research in this area.
We study non-Markovian quantum systems for communication of quantum information. The quantum capacities of an exactly solvable spin-star system are analytically determined. Our results show that they strongly depend on the bath frequencies and system-bath coupling. The Ising spin-bath becomes noisy as the bath temperature is increased decreasing its capacity to transmit information. For random couplings and bath frequencies, recurrences of coherence are small in amplitude and rapidly die out. However, full periodic recurrences occur for equal coupling and frequencies. For small number of bath spins, the capacities are higher at low temperature. We also study two time-correlated non-unital channels for the transmission of classical and quantum information, provided limited or unlimited entanglement is shared prior to the communication. The noise over two successive uses of the channel is assumed to be time-correlated Markov noise. For amplitude-damping channel, the capacities exhibit strong dependence on channel memory. They decrease as the channel noise increases and reduce to zero when noise is maximum. However, our results show that the capacities are always non-zero, in the presence of channel memory. This is similar to the superactivation phenomenon. For perfect memory channel, the capacities acquire maximum value. Finally, we determine the entanglement-assisted classical capacity of generalized amplitude-damping channel. Our results show that depending on the channel noise and system-reservoir coupling, there exists a memory threshold. Below this threshold, the capacity decreases as channel memory increases. However, the capacity increases with memory beyond this threshold and is maximum for perfect memory channels.