تقریظ اوّل
بسم اللہ الرحمن الرحیم
نحمدہٗ و نصلی علی رسولہِ الکریم
محترم حافظ محمد اکرم راشد ؔصاحب جو ایک علمی گھرانے کے چشم و چراغ ہیں اور اپنی اس وارثت کو جو علم کی صورت میں انہیں اپنے آباء واجداد سے ورثے میں ملی ہے تشِنگانِ علم کو منتقل کرنے کے لئے ہمیشہ کوشاں رہتے ہیں ۔ تدریس ہو، تقریر ہو ، تحریر ہو ، میدانِ کتابت ہو پیش پیش دکھائی دیتے ہیں ۔ بہائو الدین زکریا یونیورسٹی سے ایم۔اے عریبک میں گولڈ میڈل حاصل کیا ہے جو ہمارے علاقہ کے لئے اعزاز ہے ۔ انہوں نے ’’ نگارشات ِراشد‘ ‘ کے نام سے ایک فقید المثال کتاب تصنیف فرمائی ہے جس کا میں نے بالا سیتعاب مطالعہ کیا ہے ۔
کتاب ’’ نگارشاتِ راشد‘‘ جو مضامین پر مشتمل ہے اور اپنے اندر ندرت لیے ہوئے ہے یہ کتاب اپنے موضوع اور کتابت دونوں کے اعتبار سے نابغۂ روزگار ہے ۔ اس میں عوام النّاس کے لیے بالعموم اور طلباء کے لیے بالخصوص علمی مواد موجود ہے ۔ طلباء کے لیے ترغیبی انداز اختیار کیا گیا ہے ، مختلف موضوعات پر موصوف نے اختصار مگرجامع انداز اختیا ر کیا ہے ، اور یہ مقالات اپنے اندر علم و آگہی کا ایک وافر سامان لیے ہوئے ہیں ، موصوف چونکہ مختلف جرائد اور روزناموں میں اپنی تحریر کے گُل کھِلا تے رہتے ہیں اس لیے آپ کی اس کتاب ’’نگارشاتِ راشد‘‘ میں قاری کا تجسّس بڑھتا جاتا ہے اور صاحبِ تحریر کا جذبہ خدمت خلق پروان چڑھتا ہوا دکھائی دیتا ہے ۔ مختلف موضوعات پر مقالات تحریر کر کے طالب علم کی ضرورت کو پورا کرنے کی ہر ممکن کوشش کی گئی ہے ۔ اِن کی مذکورہ کتاب مصنّف کے علمی تبحر کی گواہ ہے ۔ اللہ تعالیٰ اِن کی اس کاوش کو مقبول فرمائے۔
پروفیسر...
The Prophet (s. a. w.) was after all a human being with perfect human nature; whatever he did in his daily life represented human nature. All of his unanimously authentic doings have been classified by legal theorists into two major categories, the doings allowed to the Prophet (s. a. w.) alone with the exclusion of his followers and the doings that were meant to explain particular apparently ambiguous sayings. The latter category is further divided into two other categories: ( I) those acts of the Holy Prophet which explicitly refer to its explanatory nature, and (r) those acts whose explanatory nature is confirmed by other source. Islamic legal theorists have unanimity over the legal status of all categories of the Prophet’s (s. a. w.) acts. Certain acts of the Prophet (s. a. w.) are mandatoryfor him but non-mandatory for his followers; certain other acts are lawful for the Prophet (s. a. w.) but unlawful for believers; some acts are obligatory for the believers; and some acts of the Prophet (s. a. w.) are mere supererogatory. There are some acts of the Prophet (s. a. w.) on which legal theorists have not said anything concerning their legal status. The present paper represents an analysis of the views of legal theorists about the acts ofthe Prophet (s. a. w.) .
Measurements of three fluidic parameters i.e. velocity / flow rate / wall shear stress, pressure and temperature are crucial in many industrial applications including aerospace, automobile, bio-medical and process control etc. The key requirement is to measure these parameters at very fine spatial resolutions, which ultimately depends upon the size of measuring device. Size minimization is possible only through Micro-Electro-Mechanical Systems (MEMS) or mirco-fabrication technology. Therefore, using a novel SOI CMOS fabrication process, this thesis develops a multi-sensing platform that measures these three fluidic parameters, simultaneously.The developed chip has dimensions of just 1.6 mm × 1.6 mm as compared with the minimum chip size of 3.8 mm × 3.8 mm reported previously, thus improving the flow spatial resolution by 82.2%. The developed multi-sensing chip includes a thermal flow sensor, a piezoresistive pressure sensor and a Resistive Temperature Detector (RTD) based temperature sensor. Before integrating these sensors in a single chip, their material and design optimization have been carried out. Ashby‟s materials selection methodology has been used to select the optimum materials for these sensors. Since no MEMS compatible materials database having micro-scale material properties was readily available, therefore first a MEMS materials database has been developed and integrated with a material selection software. The developed materials database along with the derived performance indices for these sensors has then been used to select the candidate materials. Additionally, performance of these candidate materials and the variety of promising designs has also been evaluated experimentally in a two step iterative process using SOI CMOS fabrication technology. In a first iteration, eight thermal flow sensors (i.e. having square / circular membranes and four membrane to heater length ratios), six piezoresistive pressure sensors (i.e. having square membranes, three piezoresistor materials and two piezoresistor layout designs) and twelve RTDs temperature sensors(i.e. having five different materials and six layouts) have been fabricated andexperimental characterized. The best sensor of each type in the first iteration has been further improved when integrated in the final optimized multi sensing chip. The results showed that a thermal flow sensor with a silicon oxide square membrane having a membrane to heater length ratio of 3.35 has the highest sensitivity to area ratio. Similarly, a piezoresistor pressure sensor with a square membrane having p-doped silicon piezoresistors planted at the center of each membrane edges gives maximum sensitivity. The RTDs made of p-doped silicon and having higher L/W ratio exhibited the highest sensitivity and linearity. The optimized thermal, pressure and RTD sensors are much more sensitive than the previously reported such type of sensors. .It is worth highlighting that in addition to being highly sensitive, optimized sensors reported in this research are also CMOS compatible, which make them attractive considering their low cost and ease of integration with other CMOS devices, sensors and circuits.