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Trajectory Control: Directional MWD Inversely New Wellbore Positioning Accuracy Prediction Method

Journal of China University of Geosciences 2004年第4期15卷 425-433页

作者： ahmed abd alaziz ibrahim Tagwa ahmed Musa Faculty of Engineering China University of Geosciences Wuhan 430074 China Engineering Faculty Sudan University of Science and Technology Sudan Faculty of Earth Resources China University of Geosciences Wuhan 430074 China Engineering Faculty Sudan University of Science and Technology Sudan

The deviation control of directional drilling is essentially the controlling of two angles of the wellbore actually drilled, namely, the inclination and azimuth. In directional drilling the bit trajectory never coincides exactly with the planned path, which is usually a plane curve with straight, building, holding, and dropping sections in succession. The drilling direction is of course dependant on the direction of the resultant forces acting on the bit and it is quite a tough job to hit the optimum target at the hole bottom as required. The traditional passive methods for correcting the drilling path have not met the demand to improve the techniques of deviation control. A method for combining wellbore surveys to obtain a composite, more accurate well position relies on accepting the position of the well from the most accurate survey instrument used in a given section of the wellbore. The error in each position measurement is the sum of many independent root sources of error effects. The relationship between surveys and other influential factors is considered, along with an analysis of different points of view. The collaborative work describes, establishes a common starting point of wellbore position uncertainty model, definition of what constitutes an error model, mathematics of position uncertainty calculation and an error model for basic directional service.

关键词： wellbore trajectory bit trajectory actual/planned path steerable directional tool measurement while drilling (MWD) logging while drilling (LWD) position uncertainty error accuracy prediction weighting function

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Swarming Behavior of Harris Hawks Optimizer for Arabic Opinion Mining

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Computers, Materials & Continua 2021年第12期69卷 4129-4149页

作者： Diaa Salam abd Elminaam Nabil Neggaz ibrahim abdulatief ahmed ahmed El Sawy Abouelyazed Department of Information Systems Faculty of Computers and Artificial IntelligenceBenha University12311Egypt Department of Computer Science Faculty of Computer ScienceMisr International UniversityEgypt Universite des Sciences at de la Technologie d’Oran Mohamed Boudiaf USTO-MBBP 1505EL M’naouer31000 OranLaboratoire Signal Image Parole(SIMPA)Department d’informatiqueFaculte des Mathematiques et InformatiqueAlgerie Department of Computer Science Faculty of Computers and Artificial IntelligenceBenha University12311Egypt Department of Computer Science Obour High Institute for Computers and InformaticsEgypt

At present,the immense development of social networks allows generating a significant amount of textual data,which has facilitated researchers to explore the field of opinion *** addition,the processing of textual opinions based on the term frequency-inverse document frequency method gives rise to a dimensionality *** study aims to detect the nature of opinions in the Arabic language employing a swarm intelligence(SI)-based algorithm,Harris hawks algorithm,to select the most relevant *** experimental study has been tested on two datasets:Arabic Jordanian General Tweets and Opinion Corpus for *** terms of accuracy and number of features,the results are better than those of other SI based algorithms,such as grey wolf optimizer and grasshopper optimization algorithm,and other algorithms in the literature,such as differential evolution,genetic algorithm,particle swarm optimization,basic and enhanced whale optimizer algorithm,slap swarm algorithm,and ant–lion optimizer.

关键词： Arabic opinion mining Harris hawks optimizer feature selection AJGT and OCA datasets

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Synthesis and reactions of 2-[α-(3,4-disubstituted phenacyl)-p-substituted styryl]-4H-3,1-benzoxazin-4-ones

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Chinese Journal of Chemistry 1996年第5期14卷 437-446页

作者： SOLIMAN,ahmed Youssef ATTIA,ibrahim abd El-Mogoud SALEM,Moneer abdu ibrahim SOLIMAN,El-Sayedahmed GABER,Adel Mohy El-Deen Science Department Faculty of TeachersP.O.Box 2313Al Hasa31982Saudi Arabia Faculty of Engineering Ain Shames UniversityEgypt Chemistry Department Faculty of ScienceAin Shames UniversityEgypt

Conversion ofβ-aroyl propionic acids into furanone derivatives(2)and benzoxazinone derivatives(3)for the study of the reactivity of these nucleus towards different nucleophilic and elec-trophilic reagents.

关键词： Synthesis reaction beuzoxazinone derivatives

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Cooling and lubrication techniques in grinding:A state-of-the-art review,applications,and sustainability assessment

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Chinese Journal of Aeronautics 2023年第7期36卷 76-113页

作者： ahmed Mohamed Mahmoud ibrahim Wei LI abdel-Hamid ISMAIL MOURAD Mohamed A.E.OMER Fadl A.ESSA ahmed Mustafa abd EL-NABY Mohammad S.Al SOUFI Muhammad F.EZZAT Ammar ElSHEIKH College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China Production Engineering and Mechanical Design Department Faculty of EngineeringMinia UniversityEl Minya 61519Egypt Mechanical and Aerospace Engineering Department College of EngineeringUnited Arab Emirates UniversityAl-Ain 15551United Arab Emirates Department of Production Engineering and Mechanical Design Faculty of EngineeringTanta UniversityTanta 31527Egypt Mechanical Engineering Department Faculty of EngineeringKafrelsheikh UniversityKafrelsheikh 33516Egypt Mechanical Engineering Department College of Engineering and Islamic ArchitectureUmm Al-Qura UniversityMakkah 24231Saudi Arabia Mechanical Engineering Department Faculty of EngineeringUniversity of AlbertaEdmonton T6G 2R3Canada Automotive and Tractors Engineering Department Faculty of EngineeringMinia UniversityEl Minya 61519Egypt Tokyo Institute of Technology Tokyo 152-8550Japan

Grinding technology is an essential manufacturing operation,in particular,when a component with a superfinishing and an ultra-resolution is *** the required strict quality checklist with maintaining a high level of productivity and sustainability is a substantive *** recent paper outlines the lubrication and cooling technologies and mediums that are used for ***,it provides a basis for a critical assessment of the different lubrication/cooling techniques in terms of machining outputs,environmental impact,hygiene effect,***,the paper put light on the sustainability of different cooling/lubrication *** sustainability of machining aims to get the product with the best accuracy and surface quality,minimum energy consumption,low environmental impact,reasonable economy,and minimum effect on worker’s *** paper revealed that despite some cooling/lubrication mediums like mineral oils and semisynthetic,afford sufficient lubrication or cooling,they have a significant negative impact on the environment and public *** the other hand,emulsions can overcome environmental problems but the economy and the energy consumption during grinding are still a matter of *** and vegetable oils are considered eco-friendly oils,but they suffer from a lack of thermal stability which affects their ability of efficiently *** the cooling medium with the lowest amount can achieve the goal of the economy but it may be reflected negatively on the ***,cryogenic lubrication doesn’t provide sufficient lubrication to reduce friction and hence energy *** research described in the paper is such a comprehensive compilation of knowledge regarding the machinability and machining performance under different cooling and lubrication systems that it will aid the next generation of scientists in identifying current advancements as well as potential future directions of research on ecolo

关键词： Cryogenic cooling Dry lubrication Minimum quantity lubrication Precision grinding Solid lubrication Sustainable machining Vegetable oils

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Synthetic Approaches Towards 2-（4-oxo-4, 5-Dihyd ro-Thiazol-2-yl） Acetamide

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材料科学与工程（中英文A版） 2011年第2X期1卷 228-235页

作者： Ali Khalil Shaban ibrahim Mohamed Hassan ahmed Eyada Tarek ahmed abdel alaziz Gameel ahmed Mohamed Mohamed El-Hag Ali Chemistry Department Faculty of Science Ain Shams University Cairo Egypt Technonlogy Engeneering Institute Tammoh Giza Egypt Chemistry Department Faculty of Science Al-Azhar University Cairo Egypt

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Evaluation of Urinary Hepcidin as a Marker for the Early Diagnosis of Iron Deficiency Anemia in Children

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Open Journal of Pediatrics 2020年第2期10卷 347-355页

作者： Somaia Moussa Asmaa abd-Alwakeel ibrahim Nora Mohamed ahmed El-Mansura Ad Daqahliyah Egypt Pediatrics Faculty of Medicine for Girls Al-Azhar University Al Behira Egypt Biochemistry Faculty of Medicine for Girls Al-Azhar University Cairo Egypt

Background: Iron deficiency is an essential element, because nearly all living organism urine hepcidin levels could potentially be used in the determination of iron requirements and be an accurate indicator of physiological IDA. Aim: The present study aimed to evaluate the role of urinary hepcidin as an early diagnostic marker of iron deficiency anemia in children. Methods: This study included 45 children. Their age ranged from 6 to 16 years with hemoglobin levels ≤ 11.5 gm/dL and ferritin levels ≤ 20 ng/mL. The diagnostic performance of urinary hepcidin was estimated by analyzing the receiver operating characteristic curve. Diagnostic cut-off point with a high predictive value for iron deficiency was selected. Results: This study showed no statistically significant difference between the two studied groups regarding to demographic data. There were decrease in serum iron, ferritin, hemoglobin and Red blood cells (RBCs) indices in patient than the control group. There was non-significant decrease in urinary hepcidin in the study group compared to control group. The sensitivity and specificity of urinary hepcidin in diagnoses of iron deficiency anemia was 57.8 and 62.2 respectively with positive predictive value (63.3) in our study. There was positive correlation between urinary hepcidin and mean corpuscular volume (MCV), (r = 0.221), (p = 0.036), with the cut of value Conclusion: We concluded that the decreas

关键词： Hepcidin Iron Anemia Pediatrics

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Improved RC6 Block Cipher Based on Data Dependent Rotations

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Computers, Materials & Continua 2022年第1期70卷 1921-1934页

作者： Osama S.Faragallah ibrahim F.Elashry ahmed AlGhamdi Walid El-Shafai S.El-Rabaie Fathi E.abd El-Samie Hala S.El-sayed Mohamed A.Elaskily Department of Information Technology College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Electrical Communications Faculty of EngineeringKafrelsheikh UniversityKafrelsheikhEgypt Department of Computer Engineering College of Computers and Information TechnologyTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Electronics and Electrical Communications Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt Department of Electrical Engineering Faculty of EngineeringMenoufia UniversityShebin El-Kom32511Egypt Department of Informatics Electronic Research Institute(ERI)CairoEgypt

This paper introduces an Improved RC6(IRC6)cipher for data encryption based on data-dependent *** proposed scheme is designed with the potential of meeting the needs of the Advanced Encryption Standard(AES).Four parameters are used to characterize the proposed *** parameters are the size of the word(w)in bits,the number of rounds(r),the length of the secret key(b)in bytes,and the size of the block(L)in *** main feature of IRC6 is the variable number of working registers instead of just four registers as in RC6,resulting in a variable block size for plaintext and *** IRC6 cipher is designed to improve the robustness against attacks by increasing the diffusion for each round and providing greater security with fewer *** effectiveness of the proposed IRC6 scheme is verified against theoretical *** proposed IRC6 scheme depends on full diffusion and confusion mechanisms regardless of the utilized block *** proposed IRC6 scheme saves 70%of the encryption time and 64%of the decryption time of *** simulation results prove that the IRC6 achieves a better encryption/decryption time compared to the ***,the proposed IRC6 is anticipated to fulfill the market needs and system security requirements.

关键词： Cryptography block cipher RC6,IRC6,AES

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Transgenic Date Palm Containing Endotoxin Cry3Aa Gene

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Journal of Agricultural Science and Technology(A) 2017年第4期7卷 246-257页

作者： Awatef Mahmoud Badr-Elden ibrahim abd El-Maksoud ibrahim Hamdy ahmed Emaral Mahdia Farid Gabr ahmed Abbas Nower Tamer Mahfouz abd Elaziem Department of Plant Biotechnology Genetic Engineering and Biotechnology Research Institute (GEBRI) University of Sadat CitySadat City 32897 Egypt Department of Plant Genetic Resources Desert Research Center Cairo 11753 Egypt

Date palm, like all other crops, is very sensitive to the injury by many insect pests, which may lead to the death of the affected plant and causes decrease in yield. In the present study, an efficient Agrobacterium for genetic transformation was successfully achieved for well known date palm （Phoenix dactylifera L.） cv. Medjool and Khalas using callus as explant. Embryogenic callus were recorded 100% mortality when cultured on MS medium containing 100 mg/L kanamycin with different cultivars, thus it was chosen for the selection of transformed explants. Embryogenic callus of Medjool and Khalas were incubated with Agrobacterium tumefaciens strain LBA 4404 for 0.5, 1, 2, 4 and 24 h on LB medium. After the incubation periods, embryogenic callus was transferred to MS medium with 0.1 mg/L NAA, 0.05 mg/L BA, 250 mg/L carbenicillin and 100 mg/L kanamycin for detection of transgenic embryogenic callus. Polymerase chain reaction （PCR） was used for the rapid screening of Cry3Aa gene. For screening, total genomic DNA was isolated from transformants. Using primer specific to Cry3Aa gene （forward and reverse）, a PCR product with a size of about 2,000 bp was amplified when all nucleic acid from the transformants were utilized as templates. PCR analysis confirmed the appearance of the transgene of 2,000 bp in one individual plantlet. Presence and integration of foreign Cry3Aa gene in regenerated kanamycin resistant embryogenic callus was also confirmed by Southern blot hybridization. It was found that one transgenic embryogenic callus for both Medjool and Khalas showed a single copy of gene integration. These results signify the successful transfer of Cry3Aa gene into date palm plant.

关键词： Date palm Agrobacterium tumefaciens Cry3Aa gene Southern blot analysis transformation.

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New Approach for the Synthesis of Pyrano[2,3-d]- thiazoles

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材料科学与工程（中英文A版） 2011年第5X期1卷 705-710页

作者： Mohamed Sayed abd-Elaal Elgay Shaban ibrahim Mohamed Hassan ahmed Eyada Tarek ahmed abd-El-Aziz Gameel ahmed Mohamed El-hag All Department of Chemistry Faculty of Science Al-Azhar University in Assiut Assiut 71524 Egypt Technology Engineering Institute Tamoh Giza Egypt Department of Chemistry Faculty of Science Al-Azhar University Nasr City Cairo Egypt

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Laparoscopic Rectopexy;Is It Useful for Persistent Rectal Prolapse in Children?

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Surgical Science 2014年第3期5卷 128-133页

作者： Medhat M. ibrahim Mohammed abd El Razik ahmed M. abdelkader General Surgery Unite RCMC Yanbu Industrial City KSA Pediatric Surgery Unit Faculty of Medicine Al-Azhar University Nasr City Cairo Egypt

Introduction: Rectal prolapse is a relatively common, usually self-limiting illness in children. Peak incidence is between 1 and 3 years. The intervention is required for the persistent rectal prolapse (PRP). Only scanty experience is available with laparoscopic rectopexy in children. There is no available work using both mesh and suture laparoscopic rectopexy in literature. This work is unique that it presents our clinical experience with both mesh and suture laparoscopic rectopexy in children. This is a prospective clinical study for the outcome of laparoscopic rectopexy (LRP) by both mesh and suture technique in children with persistent rectal prolapse (PRP). Materials and Methods: Fourteen cases of PRP were managed with LRP from February 2008 to August 2012. Results: Of the 14 children, 10 (71.42%) were males and 4 (28.57%) were females. Male to female ratio was 2:1. The mean age of presentation was 5 years (range 3 - 8 years). The presenting complaints were mass descending per rectum along with bleeding per rectum lasting from 1 to 3 years. All had rectal prolapse of 5 - 7 cm in length. 12 out of 14 children had recurrence even after sclerotherapy before referral to laparoscopic rectpexy. The mean duration of surgery was 30 minutes (range 20 - 60 minutes). No intraoperative complications were reported;only one case got constipation and was managed conservatively and no recurrence. Conclusion: LRP is safe, feasible in children and gives satisfactory results after failure of all conservative even sclerotherapy injection.

关键词： Rectal Prolapse Laparoscopy Rectopexy

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