Intelligent planning and control of multi-assembly systems.

The global trend towards cost minimisation in manufacturing has intensified during the last two decades. Cost reduction can be achieved either, directly, through elimination of waste, or indirectly, through optimisation of production processes and generating more reliable information regarding the costs incurred. The research presented in this thesis considers cost reduction in three aspects: optimisation of production processes, accurate cost estimation and accounting. Due to the increasing number of combinatorial optimisation problems associated with the production of Printed Circuit Boards (PCB), it has attracted the attention of many researchers who tried to solve these problems with the aim of minimising the production cost. Therefore, PCB production is used in this research as a test-bed for the three aspects mentioned above. Regarding cost reduction in PCB manufacturing, three interrelated combinatorial optimisation problems are considered: the component placement sequencing problem, the feeder assignment problem and the board type sequencing problem. Solving these problems ensures cost reduction by reducing the time required for manufacturing PCBs. As for cost reduction in the costing and accounting aspects, the traditional standard costing and standard accounting have some problems that make them unsuitable for today's manufacturing. Standard costing allocates overhead to labour or machine hours, which leads to a distortion of product costs due to the fact that today's manufacturing relies more on technology and less on human power. As for standard accounting, it has some features and characteristics that contradict with the widely spread lean manufacturing. The deficiencies in standard costing and standard accounting may create more waste and lead to the wrong decisions being taken.A framework is developed to provide solution to the above-mentioned problems in an integrated environment. A mathematical formulation for the three PCB manufacturing-related problems is developed and solved using a metaheuristic-based algorithm. In order to deal with the costing and accounting part of the framework developed, Activity Based-Costing (ABC) and Lean Accounting (LA) are implemented on a PCB manufacturing facility using a case study. ABC is used to estimate the costs of manufacturing PCBs and provide detailed information on how the costs are incurred. As for LA, it is used to reduce the costs associated with the accounting system, which is achieved by eliminating and/or replacing accounting transactions and promoting lean measures.Simulation results obtained show an average reduction in total assembly time of 5.96% and 5.43% when Taboo Search (TS) and Genetic Algorithms (GA) metaheuristics are used respectively. The results also show how ABC can be used to identify the activities used in PCB manufacturing and calculate their costs. By targeting the most costly activities identified by ABC, the production costs can be reduced. Regarding LA, the results indicate how the accounting system costs can be reduced by eliminating some accounting transactions and processes or replacing them with less costly alternatives

Continuous wave Laser CO2 efficacy in management of Basel cell carcinoma: clinical study

Objective: to study and evaluate esthetic outcomes and cure in the management of Basel cell carcinoma of face skin by using continuous wave Laser CO2. Materials and methods: a total of 12 patients (8 males and 4 females) with mean age 62 years، and diagnosed with basel cell carcinoma on face skin, were treated by traditional scalpel and vaporization of the wound  by using CO2 Laser in Tishreen university hospital. The postoperative cosmetic and cure outcomes were  recorded after 1 year of surgery. Results: 12 Tumors  had been treated: 2(17%) nodular، 7(85%) superfacial and 3(25%) pigmented. The tumors locations: 6 on zygomatic skin, 3 on temporal skin, 1 on forehead skin and 2 on upper lip. Tumors diameters are between 5.5 – 11 with average 7.7. After 1year, the cosmetic results was: 2 tumors ( 16%) bad, 7 tumors (58%) good, 3 tumors (25%) excellent. Tow tumors had been recurred. No statistically significant differences between CO2 laser surgery and cosmetic\recurrence outcomes in accord with Tumor diameter, but it is statistically significant differences in accord with Tumor type. Conclusion: CO2 Laser is effective method in management of Basel cell carcinoma of face skin, because of his good esthetic outcomes without needing of any flaps to close the wounds. هدف البحث: دراسة وتقييم الناحية الجمالية والشفاء اثناء تدبير الورم القاعدي الخلايا لجلد المنطقة الوجهية باستخدام الموجة المستمرة لليزر CO2 المواد والطرق: تتألف العينة من 12 مريض (8 ذكور و 4 اناث) متوسط العمر 62 سنة، تم تشخيص وجود ورم قاعدي الخلايا على جلد الوجه، العلاج باستئصال الورم بالمشرط  بهامش أمان 2-3 مم  و تبخير الجرح الناتج باستخدام الليزر CO2. تم متابعة الحالة لمدة سنة لمعرفة النتائج التجميلية الحاصلة بعد العلاج، و للتأكد من الشفاء الكامل. النتائج: عدد الأورام 12 ورم توزعت حسب نمط الورم بين   2 (17%) ورم عقدي ، 7 (58%) ورم سطحي، 3 (25%) ورم مصطبغ ، و قد توزعت الآفات كما يلي:6 على جلد الوجنة، 3 على جلد الصدغ ،1 على جلد الجبهة ،2على الشفة العلوية. تراوح حجم الاورام بين 5.5 – 11 مم بمتوسط 7.7 مم. بعد سنة من المراقبة توزعت النتائج من حيث الناحية الجمالية بين2 ورم( 16%) سيئة، 7 ورم (58%) جيدة، 3 أورام ( 25%) ممتازة. تعرض ورمين للنكس (16%) بعد سنة. اعتمادا على حجم الورم لم تشاهد فروق ذات أهمية من الناحية الاحصائية فيما يخص الناحية التجميلية و النكس ، بينما ظهرت الفروق الاحصائية اعتمادا على نوع الورم. الخلاصة: يعتبر الليزر CO2 أداة فعالة في تدبير الورم قاعدي الخلايا على جلد الوجه، لما له من نتائج تجميلية جيدة تعمل على تقليص الحاجة الى تسليخ النسج المجاورة من أجل الحصول على شرائح تغطي الجرح الحاصل

Intelligent planning and control of multi-assembly systems

The global trend towards cost minimisation in manufacturing has intensified during the last two decades. Cost reduction can be achieved either. directly, through elimination of waste, or indirectly, through optimisation of production processes and generating more reliable information regarding the costs incurred. The research presented in this thesis considers cost reduction in three aspects: optimisation of production processes, accurate cost estimation and accounting.. Due to the increasing number of combinatorial optimisation problems associated with the production of Printed Circuit Boards (PCB), it has attracted the attention of many researchers who tried to solve these problems with the aim ofminimising the production cost. Therefore, PCB production is used in this research as a test-bed for the three aspects mentioned above. Regarding cost reduction in PCB manufacturing, three interrelated combinatorial optimisation problems are considered: tp.e component placement sequencing problem, the feeder assignment problem and the-board type sequencing problem. Solving these problems ensures cost reduction by reducing the time required for manufacturing PCBs. As for cost reduction in the costing and accounting aspects, the traditional standard costing and standard accounting have some problems that make them unsuitable for today's manufacturing. Standard costing allocates overhead to labour or machine hours, which leads to a distorti~n of product costs due to the fact that today's manufacturing relies more on technology and less on human power. As for standard accounting, it has some features and characteristics that contradict with the widely spread lean manufacturing. The deficiencies in standard costing and standard accounting may create more waste and lead to the wrong decisions being taken. A framework is developed to provide solution to the above-mentioned problems in an integrated environment. A mathematical formulation for the three PCB manufacturing-related problems is developed and solved using a metaheuristic-based algorithm. In order to deal with the costing and accounting part of the framework developed, Activity Based-Costing (ABC) and Lean Accounting (LA) are implemented on a PCB manufacturing facility using a case study. ABC is used to estimate the costs ofmanufacturing PCBs and provide detailed information on how the costs are incurred. As for LA, it is used to reduce the costs associated with the accounting system, which is achieved by eliminating and/or replacing accounting transactions and promoting lean measures. . Simulation results obtained show an average reduction in total assembly time of 5.96% and 5.43% when Taboo Search (TS) and Genetic Algorithms (GA) metaheuristics are used respectively. The results also show how ABC can be'used to identify the activities used in PCB manufacturing and calculate their costs. By targeting the most costly activities identified by ABC, the production costs can be reduced. Regarding LA, the results indicate how the accounting system costs can be reduced by eliminating some accounting transactions and processes or replacing them with less costly alternatives.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

COVID-19-Related Acute Respiratory Distress Syndrome in a Pregnant Woman Supported on ECMO: The Juxtaposition of Bleeding in a Hypercoagulable State

A 40-year-old pregnant woman at 28 weeks of gestation was diagnosed with severe acute respiratory failure syndrome (ARDS) due to coronavirus disease 2019 (COVID-19). She had severe hypoxemia despite the use of mechanical ventilation and muscle relaxant infusion. Veno-venous extracorporeal membrane oxygenation (VV-ECMO) was used, and she had a cesarian section while on ECMO support. She developed disseminated intravascular coagulation (DIC) with overt bleeding. This was managed by a multidisciplinary team (MDT) and a change of the ECMO circuit resulted in a dramatic improvement of her coagulation profile. Both the mother and the baby were discharged and went home in good condition