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Search Results: 1 - 10 of 4399 matches for " technique "
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Solving Nonlinear Stochastic Diffusion Models with Nonlinear Losses Using the Homotopy Analysis Method  [PDF]
Aisha A. Fareed, Hanafy H. El-Zoheiry, Magdy A. El-Tawil, Mohammed A. El-Beltagy, Hany N. Hassan
Applied Mathematics (AM) , 2014, DOI: 10.4236/am.2014.51014
Abstract:

This paper deals with the construction of approximate series solutions of diffusion models with stochastic excitation and nonlinear losses using the homotopy analysis method (HAM). The mean, variance and other statistical properties of the stochastic solution are computed. The solution technique was applied successfully to the 1D and 2D diffusion models. The scheme shows importance of choice of convergence-control parameter \"\" to guarantee the convergence of the solutions of nonlinear differential Equations. The results are compared with the Wiener-Hermite expansion with perturbation (WHEP) technique and good agreements are obtained.

Kicks Controlling Techniques Efficiency in Term of Time  [PDF]
Ali K. Darwesh, Thorkild Maack Rasmussen, Nadhir Al-Ansari
Engineering (ENG) , 2017, DOI: 10.4236/eng.2017.95028
Abstract: Kicks are the result of under balance drilling operation. Time consumed to control the kicks will be different in depending on the controlling technique. Drilling fluid considered as a first barrier to control formation pressure and well kicks. Any advance in drilling fluids leads to more controlled operation in term of time. This paper will follow the general increasing profile of pressure before entering the reservoir. Both methods of well controlling technique; circulating techniques and non-circulating have been implemented in many oil blocks. The process of designing and casing selection, setting depth and many other issues is predominately dependent on the utilization of accurate values of formation pressure. Formation pressures used to design safe mud weights to overcome fracturing the formation and prevent well kicks. Hence the emphasis has been placed on the practical utilization of kicks pressure near the reservoir. The presented relationships will help the engineer to better understand lithological columns and reduce potential hole problems during the kick appearance. Selecting the best well controlling practical method can lead to not harming the reservoir and more production later. Changes in some drilling fluid properties have been proposed with increasing the depth without damaging the reservoir. Suggestions in relation to the casing setting point of the intermediate section are also proposed. Standard equations with proper modification for gases and safety margin have been proposed for the future drilling operation in oil fields above the reservoir.
Arthroscopic Surgery of the Elbow; Indications, Contra-Indications, Complications and Operative Technique  [PDF]
Frank Theodoor Gabriel Rahusen, Orthopedic Surgeon, Denise Eygendaal
Surgical Science (SS) , 2011, DOI: 10.4236/ss.2011.25049
Abstract: Arthroscopy of the elbow was first described by Burman in 1931. In this first article about arthroscopy of the elbow in the journal of bone and joint surgery, he concluded that the elbow joint was not suitable for arthroscopy; the joint was too small and the neurovascular structures in the anterior compartment of the elbow were close. In 1932 he revised his original article with some technical modifications and slowly arthroscopy of the elbow was performed more often. In the late 1980’s arthroscopic surgery of the elbow became more and more popular. In this article an overview is given of the indications for elbow arthroscopy, the surgical technique is described in detail and the possible complications are highlighted.
Depression and Insulin Resistance in Non-Diabetic Subjects: An Intervention Study with Insulin Clamp Technique  [PDF]
Shaheen Asghar, A. Magnusson, Akhtar Hussain, Lien M. Diep, Bishwajit Bhowmik, Per M. Thorsby
International Journal of Clinical Medicine (IJCM) , 2012, DOI: 10.4236/ijcm.2012.37104
Abstract: Aims: To clarify the relationship between depression and glucose metabolism using sensitive measures of insulin resistance, and to assess if remission of depression results in enhanced insulin sensitivity. Methods: An intervention study to quantify changes in insulin sensitivity before and after treatment of depression was carried out. Twenty six Pakistani women with newly diagnosed depression underwent euglycemic insulin clamp to measure insulin sensitivity at inclusion and again after treatment of depression 6 - 8 weeks later. Twenty-three individuals completed both tests. Results: Significant improvement of insulin sensitivity was observed following the treatment of depression. The improved insulin sensitivity remained statistically significant after controlling for confounding factors. Conclusions: This study establishes a relationship between depression and insulin resistance. It demonstrated that insulin sensitivity can be improved by treating depression.
Arch Reconstruction in Hypoplastic Left Heart Syndrome: Handling the Diminutive Aorta  [PDF]
Francisco J. Boye, Frank A. Pigula
World Journal of Cardiovascular Surgery (WJCS) , 2013, DOI: 10.4236/wjcs.2013.36039
Abstract: The diminutive aorta presents technical challenges in the palliation of hypoplastic left heart syndrome. Furthermore, aortic arch caliber changes and variable great vessel relationships can add complexity to an already difficult arch repair. We describe a technical approach that simplifies the aortic reconstruction and makes the procedure more generalizable and reproducible.
Benign retrorectal tumours: Contribution of laparoscopic approach  [PDF]
Victor J. Ovejero-Gomez, M. V. Bermudez-Garcia, L. Martin-Cuesta, A. Güezmes, J. Villalba, A. Ingelmo, J. M. Bajo-Arenas
Case Reports in Clinical Medicine (CRCM) , 2013, DOI: 10.4236/crcm.2013.27111
Abstract: Introduction: Presacral tumours are extremely rare entities as the asymptomatic retrorectal mass, although its clinical presentation includes infectious complications and signs of malignant degeneration. Magnetic resonance imaging is the most efficient imaging study for its diagnosis. The treatment of choice is complete surgical excision and traditional approaches are mainly through abdominal, posterior and perineal approach, depending on anatomical characteristics of the lesion. Laparoscopic excision of these retrorectal lesions has been reported in a few cases. Patients and methods: We report two cases of 38 and 24-year-old women who complained of anorectal symptoms and were diagnosed as retrorectal tumour by imaging studies. One of them was infected. Both cases were resected by means of laparoscopic techniques. There was no surgical complication and they were discharged on the 3rd and 4th postoperative day, respectively. Histopathologic findings revealed benign cystic teratoma in both cases. A follow-up after 36 months showed no recurrence. Our surgical endoscopic technique and a brief review of perioperative cares are presented and discussed. Discussion: Laparoscopic excision could be indicated in selected retrorectal tumours and a great surgeon’s resolve is always required. A meticulous dissection must be performed in order to identify and preserve vital structures. It’s only absolute contraindications seemed to be the suspicion of malignancy and operative inexperience. Conclusions: The complete laparoscopic removal of presacral lesions is a responsible surgical procedure which offers advantages from the sanitary and aesthetic point of view. This new endoscopic indication could be considered probably as a better technique than open approach in selected patients.

Study of Optical and Electrical Properties of Nickel Oxide (NiO) Thin Films Deposited by Using a Spray Pyrolysis Technique  [PDF]
Ahmed J. Hassan
Journal of Modern Physics (JMP) , 2014, DOI: 10.4236/jmp.2014.518212
Abstract: Nickel oxide (NiO) thin film has been deposited on a glass substrate at a temperature of 390°C ± 10°C using a simple and inexpensive spray pyrolysis technique. Nickel nitrate salt solution (Ni(NO3)2·6H2O) was employed to prepare the films and the film thickness was in order of 200 ± 5 nm. The structural, optical and electrical properties of NiO films were investigated using X-ray diffraction (XRD), visible spectrum, DC conductivity and Seebeck effect measurements. The results show that X-ray diffraction techniques have shown that prepared film is polycrystalline structure type cubic phase. The measurements of optical properties (transmittance (T) and absorbance (A)) of NiO films show that higher transmittance is 37.4% within the wavelength range (300 - 900 nm). Also the results have shown that the higher absorbance is 77.7%. The results of electrical properties have shown that at room temperature electrical conductivity is 1.3 × 10-5·cm)-1, and also results have shown that all the films are of p-type due to the negative Seebeck coefficient.
An Early Experience of Stapled Hemorrhoidectomy in a Medical College Setting  [PDF]
Mushtaq Chalkoo, Shahnawaz Ahangar, Naseer Awan, Varun Dogra, Umer Mushtaq, Hilal Makhdoomi
Surgical Science (SS) , 2015, DOI: 10.4236/ss.2015.65033
Abstract:

Background: Stapled hemorrhoidectomy, popularly known as Longo technique is in use for the treatment of hemorrhoids since its first description to surgical fraternity in the world congress of endoscopic surgeons in 1998. Objectives: To evaluate the feasibility, patient acceptance, recurrence and results of stapled haemorrhoidectomy in our early experience. Methods: Between Jan 2012 and Dec 2013, 42 patients with symptomatic GRADE III and IV hemorrhoids were operated by stapled hemorrhoidectomy by a single surgeon at our surgery department. The evaluation of this technique was done by assessing the feasibility of the surgery; and recording operative time, postoperative pain, complications, hospital stay, return to work and recurrence. Results: All the procedures were completed successfully. The mean (range) operative time was 30 (20 - 45) min. The blood loss was minimal. Mean (range) length of hospitalization for the entire group was 1 (1 - 3) days. Only 3 patients required more than 1 injection of diclofenac (75 mg) while as rest of the patients were quite happy switching over to oral diclofenac (50 mg) just after a single parenteral dose. All the patients returned to their routine work in less than a week’s time. The mean (range) follow-up was 6 (4 - 12) months. There were no major intraoperative or postoperative complications except for retention of urine in 8 patients. The patients are still on regular follow-up and have not had recurrence as yet. Conclusion: Stapled hemorrhoidectomy technique is a safe alternative to the traditional Milligan-Morgan technique. It can be performed as an office procedure, is well tolerated by patients and is cost effective than conventional surgical therapy.

The Technique of Shouldice in the Treatment of the Inguinal Hernias at the Hospital Sominé Dolo of Mopti (Mali) Subject of 675 Cases  [PDF]
Abdoulaye Kanté, Mamadou Alymami Keita, Idrissa Tounkara, Bréhima Bengaly, Bréhima Coulibaly, Siaka Diallo, Drissa Ouattara, Babou Ba, Drissa Traoré, Souleymane Sanogo, Djibril Traoré, MoustaphaIssa Magané, Mariam Daou, Bakary Keita, Birama Togola, Nouhoum Ongo?ba
Surgical Science (SS) , 2018, DOI: 10.4236/ss.2018.912052
Abstract: The objective was to study epidemiological and therapeutic aspects of the inguinal hernia according to the technique of Shouldice. Methodology: we realized a retrospective study, concerning the patients operated for inguinal hernia according to the technique of Shouldice in the service of general surgery of the hospital Sominé Dolo of Mopti, Mali. All the patients operated during the period of study for inguinal hernia according to the technique of Shouldice were included. The patients operated for hernia by other technique than that of Shouldice were not included. Results: The study has been realized in the service of general surgery of the hospital Sominé Dolo of Mopti (Mali). It was about a retrospective study which concerned 25 years from January, 1987 till December, 2012. 675 patients operated according to the technique of Shouldice were registered. The average age was of 49 years +/17.7. There were 90.7% (612) men. The sex-ratio is 9.7. The farmers, the housewives and the workers represented 51.1% (115). In 75.2% (508) the patients consulted for inguinal tumefaction. In operating meadow, the hernia was complicated to 246 (36.4%) patients among whom 72 cases were of recurrence. The hernia constriction was the main complication operating meadow 58.5% (48/82). The operating suites in one year were simple at 94.2% (636) of the patients; they were marked by 24 cases of recurrence, 12 cases of neuralgia, 6 cases of testicular atrophy, and 3 cases of keloid. Conclusion: The technique of Shouldice is the technique of choice for the cure of the inguinal hernia in developing countries because of the good result and its little expensive cost with compared with the other techniques using medical devices.
Implementing Lagrangean Decomposition Technique to Acquire an Adequate Lower Boundon the Facility Location Problem Solution  [PDF]
Eiman Jadaan Alenezy, Rehab F. Khalaf
Applied Mathematics (AM) , 2013, DOI: 10.4236/am.2013.48156
Abstract:

In this work, the Lagrangean Relaxation method has been discussed to solve different sizes of capacitated facility location problem (CFLP). A good lower bound has been achieved on the solution of the CFLP considered in this paper. This lower bound has been improved by using the Volume algorithm. The methods of setting two important parameters in heuristic have been given. The approaches used to gain the lower bound have been explained. The results of this work have been compared with the known results given by Beasley.

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