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Surgical Science 2017年第7期8卷 312-318页

作者： Abdullah al-Busaidi tariq al-shafei Huda al-Moqbali Sara al-Kindi Mohammed al-Saadi Nadya al-Busaidi Hani al-Qadhi College of Medicine & Health Sciences Sultan Qaboos University Muscat Sultanate of Oman

The aim of the study was to review traumatic splenic injury following blunt abdominal trauma (BAT), during the period from January 2009 to January 2015 at SQUH. The data for this study was retrospectively collected. It included 768 patients admitted to SQUH general surgery department following BAT. 43 patients with splenic injury were identified (34 males, 9 females). The mean age of patients with splenic injury was 36.0 years (34.4 years for males, 42.1 years for females). The most common mechanism of injury was motor vehicle collision (90.7%). Grade I, II are the most common grades of splenic injury. Non-Omani patients accounted for (51.2%) and most of them were pedestrians at the time of trauma. Ribs fracture is the most common injury associated with splenic injury. 36 (83.7%) patients were managed conservatively and 7 (16.3%) patients were splenectomized. Angioembolization was done for 11 (30.6%) patients. Despite the small population of Oman, high incidence of motor vehicle collision (MVC) increases the incidence of splenic injury among young age group.

关键词： Spleen Splenic Injury Blunt Abdominal Trauma Motor Vehicle Collision

Improved particle filtering techniques based on generalized interactive genetic algorithm

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Journal of Systems Engineering and Electronics 2016年第1期27卷 242-250页

作者： Yan Zhang shafei Wang Jicheng Li ATR Key Laboratory National University of Defense Technology Changsha 410073 China Institute of North Electronic Equipment Beijing 100191 China

This paper improves the resampling step of particle filtering（PF） based on a broad interactive genetic algorithm to resolve particle degeneration and particle *** target tracking in image processing,this paper uses the information coming from the particles of the previous fame image and new observation data to self-adaptively determine the selecting range of particles in current fame *** improved selecting operator with jam gene is used to ensure the diversity of particles in mathematics,and the absolute arithmetical crossing operator whose feasible solution space being close about crossing operation,and non-uniform mutation operator is used to capture all kinds of mutation in this *** result of simulating experiment shows that the algorithm of this paper has better iterative estimating capability than extended Kalman filtering（EKF）,PF,regularized partide filtering（RPF）,and genetic algorithm（GA）-PF.

关键词： particle filtering(PF) particle degeneration particle shortage broad interactive genetic algorithm

An overarching framework to assess the life-time resilience of deteriorating transportation networks in seismic-prone regions

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Resilient Cities and Structures 2022年第2期1卷 87-96页

作者： alice alipour Behrouz shafei Department of Civil Constructionand Environmental EngineeringIowa State UniversityAmesIA 50011USA

This study develops a comprehensive framework to assess the resilience of transportation networks consisting of deteriorating bridges subjected to earthquake *** this purpose,the structural capacity of highway bridges is estimated during their service life using a set of detailed finite-element models that simulate the progress of *** developed models take into consideration the main environmental stressors and determine the extent of capacity loss as a function of *** on the degraded state of structural components,seismic fragility analyses are performed to obtain a probabilistic evaluation of the extent of damageability of the existing bridges under seismic *** each transportation link normally consists of a number of bridges,the state of damage in the individual bridges is mapped to the corresponding links and a scenario-based approach is employed to estimate the resilience of the entire transportation *** demonstrate how the consequences of structural degradation can be integrated into the developed framework,the large-scale transportation network of Los Angeles and Orange counties is investigated under a series of aging and earthquake *** outcome of this study indicates how the estimates associated with the functionality measures of a transportation network can be improved if the age factor is properly integrated into the framework used for resilience assessment.

关键词： Resilience assessment Transportation networks Aging bridges Deterioration Functionality measures

Chitosan/Nanocrystalline Cellulose Biocomposites Based on Date Palm (Phoenix Dactylifera L.) Sheath Fibers

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Journal of Renewable Materials 2019年第6期7卷 567-582页

作者： Abeer M.Adel Amira M.El-shafei Atef A.Ibrahim Mona T.al-Shemy Cellulose and Paper Department National Research Center33El-Bohouth St.(Former El-Tahrir St.)DokkiP.O.12622GizaEgypt Textile Research Division National Research Center33El-Bohouth St.(Former El-Tahrir St.)DokkiP.O.12622GizaEgypt

In this study,nanocrystalline celluloses were used to enhance physical,mechanical and water vapor barrier properties of chitosan films for potential food packaging *** different mineral acids(sulfuric and phosphoric)were used to extract nanocrystalline cellulose from date palm sheath *** influence of cellulose I and cellulose II on the properties of the isolated nanocrystalline celluloses(e.g.,yield,energy and length of intra-and intermolecular hydrogen bonds,and degree of substitution)were studied *** characteristics of chitosan biocomposite film with phosphorylated nanocrystalline cellulose were compared to those with sulfated nanocrystalline *** showed that besides cellulose polymorphism,the ionic ester groups on the surface of nanocrystalline cellulose is one of the factors influencing the physical,chemical,mechanical,and water vapor barrier properties in chitosan/nanocrystalline cellulose biocomposites.

关键词： Biocomposite Cellulose I Cellulose II Nanocrystalline cellulose(NCC) physico-mechanical properties Thermal stability

Kinematic analysis of flexible bipedal robotic systems

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 795-818页

作者： R.FAZEL A.M.shafei S.R.NEKOO Department of Mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de Sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous *** distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic *** is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases ***,the human leg bones that are involved in walking are supported by viscoelastic muscles and ***,for achieving more exact results,it is essential to model the robot links with viscoelastic *** this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of *** most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational *** extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned *** overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue *** solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are *** effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

New carbazole based dyes as effective co-sensitizers for DSSCs sensitized with ruthenium(Ⅱ) complex(NCSU-10)

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Journal of Energy Chemistry 2018年第2期27卷 351-360页

作者： Praveen Naik Rui Su Mohamed R.Elmorsy Ahmed El-shafei Airody Vasudeva Adhikari Organic Materials Laboratory Department of ChemistryNational Institute of Technology Karnataka Polymer and Color Chemistry Program North Carolina State University

Herein, we report the design and synthesis of three new D-A type metal-free carbazole based dyes（S1-3）as effective co-sensitizers for dye-sensitized solar cell（DSSC） sensitized with Ru（Ⅱ） complex（NCSU-10）.In this new design, the electron rich carbazole unit was attached to three different electron withdrawing/anchoring species, viz. 4-amino benzoic acid, sulfanilic acid and barbituric acid. The dyes were characterized by spectral, photophysical and electrochemical analysis. Their optical and electrochemical parameters along with molecular geometries, optimized from DFT have been employed to apprehend the effect of the structures of these co-sensitizers on the photovoltaic performances. Further, S1-3 dyes were co-sensitized along with a well-known NCSU-10 dye in order to broaden the spectral response of the co-sensitized devices and hence improve the efficiency. The photovoltaic performance studies indicated that, the device fabricated using S1 dye as co-sensitizer with 0.2 mM of NCSU-10 exhibited improved PCE of 9.55% with JSC of 22.85 mA cm-2, VOC of 0.672 V and FF of 62.2%, whereas the DSSC fabricated with dye NCSU-10（0.2 mM） alone displayed PCE of 8.25% with JSC of 20.41 mA cm-2, VOC of 0.667 V and FF of 60.6%. Furthermore, electronic excitations simulated using time-dependent DFT, were in good agreement with the experimentally obtained results of the co-sensitizers, indicating that the exchange-correlation function and basis set utilized for predicting the spectra of the co-sensitizers are quite appropriate for the calculations. In conclusion, the results showed the potential of simple organic co-sensitizers in the development of efficient DSSCs.

关键词： Carbazole dyes DSSC DFF NCSU-10 Co-sensitization and photovoltaic performance

Projecting impact of CPEC on Pakistan’s electric power crisis

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Chinese Journal of Population,Resources and Environment 2019年第4期17卷 310-321页

作者： Sumera Iqbal Jianxun Chu shafei Moiz Hali School of Public Affairs University of Science and Technology ChinaHefeiAnhuiChina Business School Bahria UniversityIslamabadPakistan Department of Government&Public Policy National Defence UniversityIslamabadPakistan

The commencement of China–Pakistan Economic Corridor has led to the appreciation of Pakistan’s economic outlook from 5.4%to 5.8%by the World *** upgraded outlook is a welcome sign but it is still trivial,essentially attributable to the electric power crisis,which approximately trims 2%of Pakistan’s economic growth *** 60%of the CPEC(China–Pakistan Economic Corridor)funds are directed at Pakistan’s energy sector,hence,demanding careful attention of both researchers and policy analysts *** study is based upon a meta-analytic review of literature concerning CPEC and Pakistan’s energy *** results of the study demonstrate that CPEC is an easing agent for Pakistan’s energy crisis(82.30%).The results also highlight points of concern,including inadequate planning(47%),dilapidated electricity distribution system causing losses(64.7%),and an unsustainable energy mix(64.7%).The study further validates the findings via Spearman’s *** rρvalue for the possible“resolution of Pakistan’s energy crisis”is 0.5426 achieving a significance level of 98%and a corresponding p-value of *** significant negative rρvalue attained is−0.4894 which establishes the fact that lack of planning can hinder the energy crisis resolution.

关键词： CPEC FDI power crisis transmission losses energy crisis sustainable-energy mix Spearman’s rank correlation

Open Surgery for Retrieval of Patent Foramen Ovale Closure Device Embolized into Right Pulmonary Artery

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World Journal of Cardiovascular Surgery 2017年第5期7卷 67-72页

作者： Ahmad al Khaddour Adelle Dawson Hussein El shafei FRCS Glasg (C-Th) Damascus University Hospital/Locum Fellow NHS Hospitals Newcastle Underlym UK Damascus University Hospital Damascus Syria

Percutaneous Patent Foramen Ovate PFO/Atrial Septal Defect (ASD) closure has become an increasingly simplified procedure over the past decade. The main advantages of a percutaneous approach include avoidance of surgery, short procedure time and hospital stay. Device embolization is seen rarely but it can be fatal. We report this complication following a percutaneous PFO closure in a 44-year-old man. The device was embolized into the distal part of the right pulmonary artery. We removed the device surgically and closed the PFO/ASD.

关键词： Patent Foramen Ovate Atrial Septal Defect Septal Closure Device Embolization of the Right Pulmonary Artery Amplatzer Device Cardiopulmonary Bypass

Petrology and Geochemistry of Some Ophiolitic Metaperidotites from the Eastern Desert of Egypt:Insights into Geodynamic Evolution and Metasomatic Processes

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1139-1157页

作者： Abdel-Aal M.ABDEL-KARIM Mokhles K.AZER Shaimaa A.EL-shafei Geology Department Faculty of ScienceZagazig UniversityZagazig 44519Egypt Geological Sciences Department National Research Centre12622-DokkiCairoEgypt

Ophiolitic peridotites exposed in the Eastern Desert(ED)of Egypt record multiple stages of evolution,including different degrees of partial melting and melt extraction,serpentinization,carbonatization and *** present study deals with metaperidotites at two selected localities in the central and southern ED,namely Wadi El-Nabáand Wadi Ghadir,*** represent residual mantle sections of a Neoproterozoic dismembered ophiolite that tectonically emplaced over a volcano-sedimentary succession that represents island–arc *** studied metaperidotites are serpentinized,with the development of talc-carbonate and quartz-carbonate rocks,especially along shear and fault *** relics of primary minerals(olivine,orthopyroxene and Cr-spinel)are preserved in a few samples of partiallyserpentinized *** of the Cr-spinel crystals have fresh cores followed by outer zones of ferritchromite and Crmagnetite,which indicates that melt extraction from the mantle protolith took place under oxidizing *** protoliths of the studied metaperidotites were dominated by harzburgites,which is supported by the abundance of mesh and bastite textures in addition to some evidence from mineral and whole-rock chemical *** high Cr#(0.62–0.69;Av.0.66)and low TiO_(2)(al2 O3 and TiO_(2)of the orthopyroxene relics,are all comparable with depleted to highly depleted forearc harzburgite from a suprasubduction zone *** investigated peridotites have suffered subsequent phases of metasomatism,from oceanfloor hydrothermal alteration(serpentinization)to magmatic hydrothermal *** enrichment of the studied samples in light rare earth elements(LREEs)relative to the heavy ones(HREEs)is attributed to most probably be due to the contamination

关键词： ophiolitic metaperidotites partial melting melt extraction geodynamic evolution Eastern Desert Egypt

Tribological Characterization of Hybrid Metal Matrix Composites Processed by Powder Metallurgy

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Acta Metallurgica Sinica(English Letters) 2017年第8期30卷 781-790页

作者： M. Megahed M. A. Attia M. Abdelhameed A. G. El-shafei Department of Mechanical Design and Production Engineering Faculty of EngineeringZagazig UniversityP.O.Box 44519ZagazigEgypt

aluminum （al）-based aluminum oxide （al2O3） and silicon carbide （SIC） particles hybrid metal matrix com- posites were processed by powder metallurgy technique, followed by sintering at 500 ℃ and then hot extrusion. The tribological properties of these composites with different weight fractions of al2O3 and SiC were investigated; extrusion process significantly reduces the extent of porosity after cold compaction and sintering processes. Hybridization of the two reinforcements improved hardness and wear resistance of the composites. With an increase in SiC content, hardness was increased and consequently the wear resistance was enhanced also. Scanning electron microscopy observations show a better interfacial bond between matrix and reinforcements and a better distribution of the reinforcements.

关键词： Hybrid metal matrix composite Powder metallurgy Abrasive wear Hardness Porosity