اردو مصوتوں کا نظام
کلام یا گفت گو کرتے ہوئے ایسی آوازیں جن کی ادائیگی میں منہ کے اندر کسی قسم کی رکاوٹ نہیں ڈالی جاتی، ان بغیر رگڑ یا رکاوٹ کے پیدا ہونے والی آوازوں کو مصوتے کہا جاتا ہے۔ بقول گوپی چند نارنگ:
’’وہ آوازیں جنہیں پیدا کرنے کےلیے ہواکےگزرنے کاراستہ نسبتاً کُھلا چھوڑدیاجاتاہے لیکن زبان اور ہونٹوں کی مختلف حرکات سے منہ کے اندرونی حصےکی شکل میں تغیر وتبدل کیاجاتاہے۔اس طرح پیداہونے والی آوازوں کو مصوتے کہاجاتاہے۔‘‘۵۱؎
مصوتے کو انگریزی زبان میں Vowelsاور عربی زبان میں حروفِ علت کہا جاتا ہے۔مصوتے کو اردو زبان میں سُر بھی کہتےہیں۔
مصوتوں کی ادائیگی کے دوران زبان کی تین طرح کی حرکت ہوتی ہے:
۱۔زبان کی نوک جب تالو کےسخت حصے کی طرف اٹھے اس طرح نکلنے والے مصوتے اگلے (Front) مصوتے کہلاتےہیں۔
۲۔جب زبان کا درمیانی حصہ اوپرتالو کی طرف اٹھے تو اس وقت پیدا ہونے والے مصوتوں کو مرکزی (Central) یا درمیانے مصوتے کہا جاتا ہے۔
۳۔ جب زبان کی جڑیاپچھلا حصہ اوپر نرم تالو کی طرف اٹھے تو اس وقت پیداہونے والے مصوتے پچھے (Back) مصوتے کہلاتےہیں۔
ان تین طریقوں سےپیدا ہونے والے مصوتوں کوماہرین لسانیات نے مختلف حصوں میں تقسیم کیاہے۔انگریزی زبان میں مصوتوں کی تعداد پانچ ہے۔ (a.e.i.o.u) انگریزی کے ان مصوتوں کوماہر لسانیات نےمزید ذیلی مصوتوں میں تقسیم کیاہے۔اردو میں مصوتوں کی تعداد مختلف ماہرین لسانیات نے مختلف لکھی ہے۔بقول ڈاکٹر محبوب عالم خان:
’’اردو کے دس اساسی مصوتوں کی نشان دہی ان بنیادی مصوتوں کے چوکٹھے میں زبان کی بلندی، جبڑوں کے فاصلے اور لبوں کی شکل کو مدِ نظر رکھتے ہوئے کی گئی ہے۔‘‘۵۲؎
South Asia and Indian subcontinent have historically been regions of geo-strategic importance. They have been the most sought-after territories for every major World Player in each era. As a result of independence from the British in 1947, Pakistan and India emerged as two sovereign states, however, at loggerheads with each other since their very inception. The two countries have fought four deadly wars (1947-48, 1965 & 1971), including one (Kargil) after attaining the status of nuclear powers. One commonality in all these wars has been the unresolved Kashmir Issue, which remains the sorest point in the Pak-India ties to-date. These wars and many others military conflicts have resulted in the breach of peace for the region causing a much-feared nuclear threat, economic losses, disruption of social and cultural ties etc. For greater world peace, Pakistan and India need to resolve their differences/issues through bilateral negotiations, as war is no solution to any problem. For this purpose, political leadership of both the countries will have to intelligently carve out a plan to achieve the objective of peace and tranquility in the region. Both the countries need to realize that neighbours cannot be wished away. Peace in South Asia is synonymous to peace in the world.
Due to the rapid development of multimedia and communications technologies, issues related to data vulnerability and copyrights violation has increased. Digital content can be manipulated and reproduced effortlessly. Consequently, there is a considerable requirement for techniques aimed at content protection and authentication. Watermarking techniques can provide copyrights enforcement and authentication to prevent the illegitimate use of digital content. These techniques can be classified into two categories i.e. robust watermarking and reversible watermarking. In this thesis, research work is carried out in three phases. The first phase proposes a robust watermarking technique, which is resilient against the geometrical attacks. It is helpful in executing copyright protection. In robust watermarking, watermark is able to survive in case of attack on the digital content and can be successfully retrieved on extraction. The proposed technique exploits both the robust image feature points and local Zernike moments for embedding secret information. Delaunay tessellation is employed to divide an image into distinct triangular segments based on robust features identified using Harris detector. Zernike moments are calculated for each selected triangular segment, and then the watermark is embedded in the magnitude of Zernike moments using dither modulation. In the second phase, a reversible watermarking technique is proposed. Reversible watermarking is a special type of watermarking technique in which watermark is extracted along with restoration of the host media. Whereas, in case of robust watermarking, we are not able to retrieve the original image. Such watermarking system finds its application in medical and law enforcement, etc. The proposed watermarking scheme is based on pixel value ordering. Image is divided into sub blocks and each block is assessed using a threshold value. If the block belongs to the smooth category, watermark bit is embedded. In contrast, if it is classified as rough block, then the sub block is left unchanged. This technique does not require a location map since it uses histogram shifting. In third phase, the watermarking approaches and their applications for the protection DNA sequences are explored. In DNA watermarking, which is type of text watermarking; watermark information should be embedded in DNA sequence in such a way that it should not raise any functional disorders in the living organism. A watermark is embedded in a DNA sequence through synonymous substitution of nucleotides. The proposed approach ensures Amino Acid conservation, efficient utilization of the available embedding space in DNA sequences, and achieves mutation resistance by since it employs Reed-Solomon codes. The performance of these techniques has been evaluated on the standard test datasets. In some of the cases, the proposed watermarking approaches performed better than the recent existing approaches and showed comparable performance in other cases. The first technique finds its application in protecting the copyrights of the owner. The second watermarking technique can be used in applications where significant amount of data needs to be embedded e.g. information related to the patient in medical images. The third technique related to the DNA watermarking can be used for protection of DNA sequences and also to provide biological data storage as large amount of data can be stored.