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Mechanical and Metallurgical Characterization of HSLA X70Welded Pipeline Steel Subjected to Successive Repairs

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Acta Metallurgica Sinica(English Letters) 2016年第6期29卷 568-576页

作者： Bouzid Maamache Mabrouk bouabdallah Abdelhalim Brahimi Youcef Yahmi Billel Cheniti Brahim Mehdi Research Center in Industrial Technologies(CRTI) P.O.Box 6416014 CheragaAlgeria Laboratoire des Aeronefs Universite de Blidal09000 BlidaAlgeria LGSDS Ecole Nationale PolytechniqueEl Harrach16200AlgiersAlgeria LTSM Universite de Blidal09000 BlidaAlgeria ICMMO/SP2M Bat 410Universite Paris-Sud 1191405Orsay CedexFrance

The aim of this work is to study the influence of successive weld repairs on the microstructure and the mechanical behavior of the heat-affected zone（HAZ） of an HSLA X70 steel. Detailed microstructural examination combined to grain size measurement showed that beyond the second weld repair, the microstructure of the HAZ undergoes significant change in the grain morphology and grain growth. The results of the X-ray diffraction analyzed using MAUD software indicated an increase in the crystallite size and a decrease in the dislocation density according to the number of weld repair operations. Consequently, a loss of mechanical properties, namely the yield strength and the toughness with the number of weld repairs, was recorded. Beyond the second weld repair operation, the properties of the welded joint do not fulfill the standards applied in piping industry.

关键词： HSLA X70 steel Successive weld repair Heat affected zone Dislocation density

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氢气和过氧化氢对正癸烷燃烧特性影响的对比

航空动力学报 2017年第11期32卷 2596-2603页

作者： Gribi bouabdallah 惠鑫林宇震郑东生北京航空航天大学能源与动力工程学院北京100191

氢气(H2)和过氧化氢(H_2O_2)具有较强的反应活性,能够增强碳氢燃料的燃烧过程。为了探究添加液态氢和液态过氧化氢对航空燃油燃烧特性的影响,以正癸烷为代理燃料,采用数值模拟方法对比研究了H2和H_2O_2对正癸烷/空气燃烧特性的影响。研... 详细信息

氢气(H2)和过氧化氢(H_2O_2)具有较强的反应活性,能够增强碳氢燃料的燃烧过程。为了探究添加液态氢和液态过氧化氢对航空燃油燃烧特性的影响,以正癸烷为代理燃料,采用数值模拟方法对比研究了H2和H_2O_2对正癸烷/空气燃烧特性的影响。研究发现,随着H_2O_2的增加,点火延迟时间显著缩短;而随着H2的增加,初始温度为1100K时,点火延迟时间基本不变,在初始温度为1 600K时点火延迟时间略有缩短。随着H_2O_2的增加,层流火焰速度有所提升,而H2添加量对层流火焰速度的提高相对而言较小。富油燃烧时,CO排放指数随H_2O_2和H2的增加有所降低,NO排放指数有所增长。低压贫油燃烧时,H_2O_2和H2添加量对CO和NO排放指数基本没有影响;高压贫油燃烧时CO排放指数有所降低,NO排放指数有所提高,H_2O_2添加量的影响更加显著。

关键词：液态氢液态过氧化氢燃烧特性正癸烷 CO排放指数 NO排放指数

Energy Conservation in Reliable Wireless Sensor Networks

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Energy Conservation in Reliable Wireless Sensor Networks

Mandibular Reconstruction in Cervical Desmoid Tumors

2008 IEEE International Conference on Communications(ICC 2008)

作者： Fatma bouabdallah Nizar bouabdallah Raouf Boutaba INRIA-IRISA Campus de Beaulieu 35042RennesFrance School of Computer Science University of Waterloo

Energy-efficiency is one of the major concerns in wireless sensor networks since it impacts the network *** this paper,we investigate the relationship between sensor network performance,particularly its lifetime,and the number of active reporting nodes N by using both analytical and simulation *** first demonstrate that decreasing the number of reporting nodes increases the number of reports that need to be sent to the sink,in order to achieve the desired information reliability regarding the detected *** the other hand,we show that reducing the number of reporting nodes alleviates the energy wastage due to *** on this tradeoff,and as a main contribution,we derive the optimal number of reporting nodes N opt energy that minimizes the energy consumed to report reliably the occurrence of an *** other words,we prove that limiting the reporting tasks of a detected event to a small subset of sensor nodes （i.e.,N opt energy）,instead of using all the sensor nodes in the event area,enables significant energy conservation.

关键词： Energy conservation Wireless sensor networks Peer to peer computing Event detection Energy consumption Energy efficiency Media Access Protocol Routing protocols Communications Society Computer network reliability

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Open Journal of Pediatrics 2021年第3期11卷 398-405页

作者： Ayoub Boutahar Imane Oualili Abdelhalim Mahmoudi Khalid Khattala Youssef bouabdallah Department of Pediatric Surgery Faculty of Medicine and Pharmacy of Fez University Hospital Center Hassan II Fes Morocco

Introduction: Desmoid tumors are benign soft tissue tumors, but their infiltration character is responsible for big morbidity, especially in the cervicofacial location. Their management, therefore, represents a real challenge. Clinical case: Reporting a case of a 4-year-old girl presenting a desmoid tumor at the expense of the mandibular corpus and the right ascending ramus, with loco-regional infiltration, and whose treatment consisted of surgical resection of the tumor with Hemi-mandibulectomy and reconstruction according to the Masquelet technique. Conclusion: The traditional treatment consists of a large local excision with negative surgical margins. Head and neck fibromatosis, while rare, present a complex problem as they are often aggressive, and invade local bone, nerve and muscles, and can leave patients with a cosmetic deformity. In our case, it was a mandibular reconstruction after a large resection of a desmoid tumor with a location on the head and neck. With good consolidation, absence of recurrence, and without aesthetic sequelae at the control.

关键词： Desmoid Tumor Fibromatosis Surgery Masquelet

The Pre-Diagnosis History of Gynecologic Tumors in Children

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Open Journal of Pediatrics 2023年第2期13卷 207-213页

作者： Othmane Alaoui Fatoumata Binta Baldé Abdelhalim Mahmoudi Khalid Khattala bouabdallah Youssef Department of Pediatric Surgery Hassan II University Hospital of Faz Fez Morocco Faculty of Medicine and Pharmacy Sidi Mohamed Ben Abdallah University Fez Morocco

Introduction: Gynecologic tumors represent less than 5% of all solid tumors in children. Patients and Method: Through a prospective and descriptive study over 4-years, we included girls aged less than 15 years admitted for a gynecologic tumor. We collected and analyzed the medical data, and paid particular attention to the pre-diagnosis history. Results: Eleven girls met our criteria with a mean age of 8.5 years (2 - 13 years). Abdominal pain, abdominal distension or protrusion of a vaginal mass was the main symptoms. The patients were seen at least by one doctor outside the surgical structure [1] [2] [3]. Four of eleven were received by two different doctors before carrying out the evocative radiological assessment. The average consultation delay was 7-months (24 hours to 18 months). There were nine ovarian tumors and two vaginal tumors. The histological study revealed five of eleven (45%) malignant tumors. Conclusion: Gynecological tumors in children are rare. However, there is a significant proportion of malignant tumors. All doctors can be confronted with it and should not delay the radiological assessment.

关键词： Gynecologic Tumor Diagnostic Children

Appendicular Abscess: Unusual Clinico-Radiological Appearance

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Open Journal of Pediatrics 2022年第4期12卷 647-651页

作者： Ayoub Boutahar Imane Oualili Abderrahim Kamli Othman El Alaoui Abdelhalim Mahmoudi Khalid Khattala Youssef bouabdallah Department of Pediatric Surgery Faculty of Medicine and Pharmacy of Fez University Hospital Center Hassan II Fes Morocco

Introduction: Appendicitis is the most common surgical emergency in childhood. It’s a common surgical disease that can be presented with a wide variety of atypical clinical features. Clinical Case: We report a case of a 7-year-old female patient admitted for abdominal pain dating back 20 days, radiological exploration suggested a right ovarian teratoma, while laparoscopic exploration has objective an appendicular abscess. Conclusion: This case has allowed us to clarify an atypical case of complicated appendicitis, and also to show the contribution of laparoscopy.

关键词： Appendicular Abscess Ovarian Teratoma Laparoscopic Exploration

Energy-Efficient Methods for Highly Correlated Spatio-Temporal Environments in Wireless Sensor Network Communications

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Wireless Sensor Network 2014年第5期6卷 67-92页

作者： Mohammad Abdul Azim Zeyar Aung Sofiane Moad Nizar bouabdallah Mario E. Rivero-Angeles Israel Leyva-Mayorga DYONISOS INRIA Rennes France Masdar Institute of Science and Technology Abu Dhabi UAE National Polytechnique Institute CIC-IPN Mexico City Mexico National Polytechnique Institute SEPI ESCOM-IPN Mexico City Mexico

Continuous-monitoring (CM) of natural phenomenon is one of the major streams of applications in wireless sensor networks (WSNs), where aggregation and clustering techniques are beneficial as correlation dominates in both spatial and temporal aspects of sensed phenomenon. Conversely, in Event Driven Reporting (EDR), the efficient transmission of sensitive data related to some predefined alarm cases is of major importance. As such, reporting latency is a more important performance parameter. However, in some applications, the transmission of both CM and EDR data is encouraged or even required. For either CM or EDR applications, system performance can be greatly improved when both the number of packets to be transmitted as well as the packet size is reduced. This is especially true for highly dense sensor networks where many nodes detect the same values for the sensed phenomenon. Building on this, this paper focuses on studying and proposing compression techniques to improve the system performance in terms of energy consumption and reporting latency in both CM and EDR applications. Furthermore, we extend our analysis to hybrid networks where CM and EDR are required simultaneously. Specifically, this paper presents a simple aggregation technique named smart aggregation (SAG) for the CM applications and an event driven scheme named compression cluster scheme in spatial correlated region (CC_SCR). The proposed SAG exploits both spatial and temporal correlations where CC_SCR exploits the spatial correlation of such networks by data compression. Rationalizing the developments is attained by simulations that compare energy efficiency of the proposed SAG with k-hop aggregation and CM based event driven reporting (CMEDR) schemes. Results of CC_SCR show that the technique may reduce the energy consumption drastically. In some specific cases the reduction becomes more than 10 times compared to a classical clustering scheme. Two different strategies for the transmission of event

关键词： Wireless Sensor Networks Aggregation Continuous-Monitoring Event Driven Reporting Data Compression Clustering

Corticosurrenaloma: About a Pediatric Case

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Open Journal of Pediatrics 2022年第2期12卷 449-452页

作者： Thierry Mukenge Wa Mukengeshay Fatoumata Binta Balde Zineb Benmassaoud Priscilla Kinsala Othmane Allaoui Abdelhalim Mahmoudi Khalid Khattala Sara Benmilloud Youssef bouabdallah Service de Chirurgie Pédiatrique Centre Hospitalier et Universitaire Hassan II de Fès Fès Morocco Service de Pédiatrie Unité d’Oncologie Centre Hospitalier et Universitaire Hassan II de Fès Fès Morocco Faculté de Médecine et de Pharmacie Université Sidi Mohamed Ben Abdallah de Fès Fès Morocco

Introduction: This study aims to describe the outcome of adrenocortical cancer in children through observation. Observation: A 10-year-old girl with no previous pathological history. She presented headaches and severe hypertension with clinical and biological signs of hyperandrogenism for 6 months. An abdominal CT scan showed an encapsulated left adrenal mass without local or regional invasion or secondary location. A pheochromocytoma or adrenal neuroblastoma was first suspected. The blood pressure was stable at 130/65 mmHg under antihypertensive drugs. She underwent a complete tumor resection without any intraoperative incident. The pathologic study confirmed the adrenocortical carcinoma scored Weiss 7. The severe high blood pressure reappeared 2-year later despite antihypertensive drugs. The thoracic abdominal and pelvic CT scan showed a locally advanced tumor recurrence in the left adrenal gland with parenchymal nodes in the lungs and liver. The outcome was fatal despite medical and surgical management. Conclusion: Adrenocortical cancer is a rare tumor. It is important to hormonal testing in the presence of Cushing’s syndrome in children. It can give a strong indication of the diagnostic possibilities. Histology confirms the diagnosis. The evolution is covered by complications, in particular recurrence with life-threatening metastases.

关键词： Adrenal Tumor Adrenal Cortex Hyperandrogenism Child

Post-Traumatic Gallbladder Injury in Children: Case Rapport

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Open Journal of Pediatrics 2020年第3期10卷 570-575页

作者： F. B. Balde T. Mukengue I. Oualili Z. Benmassaoud K. Khatalla A. Mahmoudi Y. bouabdallah Sidi Mohamed Ben Abdallah University Hassan II University and Hospital Center Fez Morocco

Post-traumatic injuries of the gall bladder are rare. We report through a clinical description of its physio-pathological and evolutionary aspects. A 14-year-old boy was received 48 hours after a stabbing attack. After initial haemorrhage, the patient presented clinical improvement;then a sudden deterioration with vague symptoms and disturbance of the hepatic balance. The abdominal CT scan revealed a perivesicular hematoma with a focus on hepatic contusion. Laparoscopy showed a penetrating sore of the liver, but the exploration was limited by an important inflammation of the digestive tract. The diagnosis of gall bladder perforation was made during the operation. We performed a cholecystectomy by laparotomy. Postoperative evolution was simple, removal of the slides at D + 4 and discharged at D + 7 postoperative after improvement. At the 6th month, he presented an acute intestinal obstruction on bridles, managed at emergency by open surgery. After one year of follow up, the patient has no symptoms. We note that the vague clinical presentation and the limit of imaging examinations made the early diagnosis of a vesicular perforation a real challenge for the clinician. Cholecystectomy remains the optimal treatment.

关键词： Gall Bladder Trauma Perforation