Queueing Network Models (QNMs) with Finite Capacity provide powerful and realistic tools for the performance evaluation and prediction of discrete flow systems such as computer systems, communication networks and flexible manufacturing systems. Over recent years, there has been a great deal of progress towards the analysis and application of QNMs with finite capacity, and high quality research work has appeared in diverse scientific journals of learning and conference proceedings in the fields of Operations Research, Computer Science, Telecommunication Networks, Management and Industrial Engineering. However, there are still many important and interesting finite capacity queues and QNMs to be resolved, such as those involving multiple-job classes, bounds and theoretical properties, exact analysis, numerical solutions and approximate methods, as well as application studies to computer and distributed systems, high-speed networks and production systems. Finite capacity queueing network models (QNMs) also play an important role towards effective congestion control and quality of service (QoS) protection of modern discrete flow networks. Blocking in such networks arises because the traffic of jobs through one queue may be momentarily halted if the destination queue has reached its capacity. Exact closed-form solutions for QNMs with blocking are not generally attainable except for some special cases such as two-station cyclic ivqueues and ‘reversible’ queueing networks. As a consequence, numerical techniques and analytic approximations have been proposed for the study of arbitrary QNMs with non-Markovian (external) inter- arrival and service times under various types of blocking mechanisms. This research mainly focuses on: i) To develop and validate cost effective analytical models for arbitrary QNMs with blocking and multiple job classes. ii) To use the analytical models to evaluate the performance of QNMs under various blocking mechanisms applicable to flexible manufacturing systems and high speed telecommunication networks. iii) To develop approximate analytical algorithms for arbitrary QNMs consisting of G/G/1/N censored-type queues with arbitrary arrival and service processes, single server under Partial Buffer Sharing (PBS) and Complete Buffer Partitioning (CBP) schemes stipulating a sequence of buffer thresholds {N=N1,N2,...,NR,0< Ni ≤ Ni-1 , i=1,2,...,R} and buffer partitioning with FCFS service discipline. {chapter 4 and 5} iv) Validation of these algorithms (iii) using QNAP simulation package. v) Extension of the above algorithms for multiple servers and its validation using simulation. Determining a performance distribution via classical queueing theory may prove to be an infeasible task even for systems of queues with moderate complexity. Hence, the principle of entropy maximization may be applied to characterize useful information theoretic approximations of performance distributions of queueing systems and queueing network models (QNMs). vFocusing on an arbitrary open QNM, the ME solution for the joint state probability, subject to marginal mean value constraints, can be interpreted as a product-form approximation. Thus, the principle of ME implies a decomposition of a complex QNM into individual queues each of which can be analyzed separately with revised inter arrival and service times. Moreover, the marginal ME state probability of a single queue, in conjunction with suitable formulae for the first two moments of the effective flow, can play the role of a cost-effective analytic building block towards the computation of the performance metrics for the entire network.
{امتیاز اوجھلؔ (۱۹۴۲ء۔۲۰۱۱ء) کا اصل نام رحمت علی اور اوجھلؔ تخلص کرتے تھے۔ وہ کوٹلی لوہاراں ضلع سیالکوٹ میں پیدا ہوئے۔ آپ ساحرؔ، عدمؔ ،جوشؔ اور فیضؔ سے بہت متاثر ہیں۔ ان کے کلام میں چاروں شعراکا رنگ اور اسلوب نظر آتا ہے۔ ان کا ابتدائی شعری کلام ماہنامہ’’گلِ رو‘‘ کراچی میں شائع ہوا۔ آپ ترقی پسند تحریک سے بھی منسلک رہے۔ (۹۶۹) ان کا پہلا شعری مجموعہ ’’نویدِ سحر‘‘ ۱۹۹۵ء میں شائع ہوا۔ دوسرا شعری مجموعہ ’’اجاڑ جنگل اداس موسم‘‘ ادارہ تخلیقات لاہور نے ۱۹۹۹ء میں شائع کیا ۔ تین شعری مجموعوں کے مسودے راقم الحروف نے انٹر ویو کے دوران ان کے پاس دیکھے جن کے نام ان دنوں زیر غور تھے۔
امتیاز اوجھلؔ غزل کے شاعر ہیں لیکن انھوں نے دیگر اصناف سخن میں طبع آزمائی بھی کی ہے۔ امتیاز انقلابی اور مزاحمتی شاعر ہیں۔ ان کی شاعری میں قدیم روایات سے بغاوت نظر آتی ہے۔ روشن خیالی کا اچھوتا پن ان کی شاعری میں بدرجہ اتم موجود ہے ان کی شاعری میں فکری گہرائی، حیاتِ تازہ کی طرف بلانے والی رہنمائی ،ہوش و خرد میں لپٹے ہوئے جذبوں کا والہانہ اظہار اور فرسودہ معاشرتی طرزِ زندگی پر ایک تعمیری ،مـثبت اور تنقیدی تبصرہ ملتا ہے جو تاریک اور خاموش سناٹوں میں لہراتی ہوئی روشنی کی گونج دار لکیر کی طرح اپنے وجود کا منظر پیش کرتا ہے۔آپ لفظوں کی نئی نئی ترکیبیں ،بندشیں اور استعارے اپنے من چاہے روپ میں ترتیب دیتے ہیں۔ فکری شاعری میں فلسفہ اور جدید سائنس کے متعلقہ پہلوؤں کو نظم کرنا خاصا مشکل مرحلہ لگتا ہے۔ اس کوشش میں امتیازاوجھلؔ کی یہ کوشش اردو شاعری میں ایک قیمتی اور درخشندہ اضافہ سے کم نہیں۔وہ جدید فلسفے کاایک اہم اور مشکل موضوع جدلیاتی مادیت اپنی شاعری میں بڑے خوبصورت انداز میں نظم کرتے ہیں:
The scholars of Hadith gave special attention to the fabricated hadith and they explained it to others and warned about its danger. They all agreed upon it that transmission of fabricated report is unlawful only one way is lawful if the status of this report is narrated with its transmission. Some great scholars of hadith like Mizzi, Zahabi and Ibn Hajr have pointed out that in the sunan of Ibn Maja there are some fabricated and false ahadith. I took interest in study of these fabricated ahadith and I separated them and studied these ahadith according to the Principles of research of this filed. You will find during the study of this paper the importance of Sunan among the six books. You will study comments of scholars about this book. After complete study of this paper, we can conclude following points: 1. There are forty-four fabricated ahadith in Sunan of Ibn Maja. 2. These ahadith are found in five books except one, hadith is narrated by only Ibn Maja. 3. Ibn Maja declared about only one hadith that it is baseless. 4. Ibn Juzi mentioned only seven ahadith in his book fabricated ahadith. 5. Imam Bausairi showed indefference in commenting and declaring these ahadith as fabricated in his book Misbah-uz- zujazah. Although there are clear signs of fabrication in these ahadith.
Medicinal chemistry is a discipline associated with the designing, synthesis, and development of drugs used in different pathophysiological conditions. Small organic compounds or biologics are mostly studied in medicinal chemistry but the key focus is on small molecules to develop new synthetic agents for human use. These small molecules are usually heterocyclic compounds, hold a ring in their structure along with heteroatoms in addition to the carbon. Heterocyclic compounds are abundantly present in nature and very important from the therapeutic and economic point of view. Detailed information on the pharmacological activities of each organic compound is a challenge for the medicinal chemists because a large of number of synthetic organic compounds has been prepared currently. Therefore, the idea of structure activity relationship has been used to explain the variation in biological activity of organic compounds. Structure activity relationship is used in lead optimization to improve the efficacy and minimize the toxicity of the molecules. The biology oriented synthesis "BIOS" is a starting point for the search of new therapeutic agents. It is an approach for the generation of libraries of compounds for their biological applications. Non-steroidal anti-inflammatory drugs are an important class of organic compounds, having widespread applications in different diseases and most commonly used as analgesic, antipyretic and anti-inflammatory agents. They are used for the management of various acute and chronic inflammatory conditions alone or in combination with opioid analgesics. Oxicam is comparatively a new class of drugs consists of enolic acid compounds which possess analgesic and anti-inflammatory effects. Their structure contains 1, 2-benzothiazene nucleus, substituted at position-3 with carboxamide. Piroxicam belongs to the oxicam family discovered in 1972. It is the first member of this class and has marked analgesic and antipyretic properties and therefore, has been used clinically for the treatment of persistent inflammatory disorders for the last 30 years. Chemically, piroxicam is 4-hydroxy-2-methyl-2H-1, 2-benzothiazine-1-(N-(2 pyridinyl) carboxamide)-1, 1-dioxide. It is a heterocyclic compound and consists of benzene and thiazine rings. Benzo represents benzene while thiazine represents a six-membered ring in benzothiazine. It acts by blocking the cyclooxygenase enzymes and inhibiting the synthesis of prostaglandins. Due to the existence of enolic hydroxy (OH) group, piroxicam presented fascinating structural properties which prompted the medicinal chemists and pharmacologists for further research. The present study was designed to synthesize and characterize the piroxicam derivatives and screened them for in-vivo and in-vitro biological activities. Piroxicam derivatives (1-18) were prepared by dissolving piroxicam with commercially available alkyl/aryl sulfonyl chloride and triethylamine in tetrahydrofurane as a solvent, in a round bottom flask with constant stirring at room temperature. After the completion of the reaction, the resulting products were filtered, washed with hot n-hexane and excess of solvent was removed under vacuum at reduced pressure. Different spectroscopic procedures like 1H-NMR, EIMS, IR, UV and CHN analysis were used for structural elucidation of newly synthesized piroxicam derivatives and subjected to biological screening in order to prove that changing the substituent''s modifies the inhibitory potential of the individual derivative as an evident of structure activity relationship studies. The compounds were evaluated for the antinociceptive activity at 5, 10, 20 and 30 mg/kg doses. The compounds were found to be active in acetic acid induced writhing test but inactive in hot plate test for analgesia, indicating that the compounds only possess the peripheral mechanism and no central mechanism is involved as compared with standards piroxicam and tramadol respectively. Anti-inflammatory activity was determined in the carrageenan induced paw edema model in mice. The derivatives were tested at 10, 20 and 30 mg/kg doses and most of them were found to be significantly potent as compared with standard piroxicam. The piroxicam analogues when screened for the antipyretic effect in Brewer’s yeast induced pyrexia model in mice at 10, 20 and 30 mg/kg doses, the prominent antipyretic effects were observed as compared with standard paracetamol. The results showed that the compounds exhibited significant (*P < 0.05, **P < 0.01 and ***P < 0.001.) dose dependent antinociceptive, anti-inflammatory and antipyretic activities when compared with standards. The analogues were found to be safe in acute toxicity test at the doses of 50, 100 and 150 mg/kg i.p., and no gross mortality or behavioral changes were observed during 24 hours assessment time. The piroxicam derivatives were also screened for the different in-vitro activities. In in-vitro antiglycation assay, the compounds showed varying degree of antiglycation potential when compared with standard “rutin”. Compound 2, 4, and 7 exhibited excellent antiglycation activity with better potency than the reference. In in-vitro 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium cytotoxicity assay, piroxicam derivatives exhibited varying degree of cytotoxic activity against breast cancer cell lines when compared with standard “doxorubicin”. Compound 4, 17 and 18 showed moderate anticancer activity while compound 3 showed low growth inhibitory activity. The derivatives were also screened for the in-vitro immunomodulatory activity against the standard “ibuprofen”. None of the compound was found to be active in the in-vitro immunomodulatory activity. It concludes that, changing the substituent or changing the position of substituent on aromatic ring does not impart any activity to the compounds. Results of in-vitro dipeptidyl peptidase-IV inhibitory assay showed that the substitution does not noticeably change the activity of the compounds but impart a weak inhibitory activity to the compounds 1, 4, 11, 13 and 14. Other piroxicam derivatives of this series were inactive toward in-vitro dipeptidyl peptidase-IV inhibitory assay. In case of in-vitro leishmanicidal activity, compounds 7, 8, 10, 13, 14 and 17 showed good to low leishmanicidal activity while other compounds of this series having less than 100 % inhibition values and therefore concluded them as inactive. It can be concluded that, some piroxicam derivatives possess potent, good/low in-vitro antiglycation, anticancer, dipeptidyl peptidase-IV inhibitory and leishmanicidal potential as compared with standards but inactive in in-vitro immunomodulatory activity. Findings of this research work strongly support the use of piroxicam derivatives as analgesic, antipyretic, anti-inflammatory, anti-glycating, dipeptidyl peptidase-IV inhibitors, leishmanicidal and anticancer agents. However, further comprehensive research work on piroxicam derivatives as well as their use for selective inhibition of cyclooxygenase-2 enzyme is necessary in order to minimize the gastrointestinal complications.