检索结果-南通市图书馆

μPMU-based smart adaptive protection scheme for microgrids

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 887-898页

作者： mohamed Salah ELBANA Nabil ABBASY Ashraf MEGHED Nahil shaker Electrical Engineering Department Faculty of EngineeringAlexandria UniversityLotfy El-Sied St.P.O.ElhadaraAlexandria 21544Egypt

The concepts of microgrids(MGs)and smart grid represent the recent targeted revolution towards fully smart electrical network integrated with high penetration of renewable energy sources(RESs).The protection system of MGs becomes a challenge due to variable characteristics of its currents,bidirectional power flow and output power fluctuations of RES,causing selectivity and sensitivity issues for conventional protective devices(PDs)with fixed *** this paper,a smart protection scheme(SPS)is proposed using micro-phasor measurement units(μPMUs)to obtain the continuous rapid synchronized phasor measurement *** it is communicated with a microgrid central controller(MGCC)through highly reliable communication architecture to carry out online smart adaptive protection *** index coefficients and abnormality coefficients are calculated for each feeder to detect the fault location and the abnormality *** modeling of an MG including 10-bus connected distribution system with integrated distributed generation(DG)is simulated using ETAP *** proposed protection algorithm is modeled and evaluated using MATLAB *** proposed fault detector and abnormality detector can enable quick and accurate fault identification and isolation.

关键词： Fault index coefficients Microgrid(MG) Micro-phasor measurement unit(μPMU) Renewable energy source(RES) Smart protection scheme(SPS)

Hydraulic and volume change behaviors of compacted highly expansive soil under cyclic wetting and drying

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2023年第2期15卷 486-499页

作者： mohamed Farid Abbas Abdullah Ali shaker Mosleh A.Al-Shamrani Civil Engineering Department College of EngineeringPrince Sattam bin Abdulaziz UniversityAl KharjSaudi Arabia Soil Mechanics and Geotechnical Engineering Research Institute Housing and Building National Research Center(HBRC)GizaEgypt Bugshan Research Chair in Expansive Soils Civil Engineering DepartmentCollege of EngineeringKing Saud UniversityRiyadhSaudi Arabia

The wide engineered application of compacted expansive soils necessitates understanding their behavior under field *** results of this study demonstrate how seasonal climatic variation and stress and boundary conditions individually or collectively influence the hydraulic and volume change behavior of compacted highly expansive *** cyclic wetting and drying(CWD)process was applied for two boundary conditions,*** stress(CS)and constant volume(CV),and for a wide range of axial stress *** adopted CWD process affected the hydraulic and volume change behaviors of expansive soils,with the first cycle of wetting and drying being the most *** CWD process under CS conditions resulted in shrinkage accumulation and reduction in saturated hydraulic conductivity(k sat).On the other hand,CWD under CV conditions caused a reduction of swell pressure while has almost no impact on k *** elastic response to CWD was achieved after the third cycle for saturated hydraulic conductivity(k sat),the third to fourth cycle for the volume change potential under the CV conditions,and the fourth to fifth cycle for the volume change potential under the CS ***,both swell pressure(s s)and saturated hydraulic conductivity(k sat)are not fundamental parameters of the expansive soil but rather depend on stress,boundary and wetting conditions.

关键词： Expansive soils Hydraulic conductivity Volume change potential Cyclic wetting and drying(CWD) Swell pressure

Conjunctival flap advancement with or without scleral graft for hypotony maculopathy after trabeculectomy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2020年第7期13卷 1079-1086页

作者： Abdelhamid shaker Elhofi mohamed Fahmy Doheim Amir AbouSamra Department of Ophthalmology Faculty of MedicineAlexandria UniversityAlexandria 21131Egypt Faculty of Medicine Alexandria UniversityAlexandria 21131Egypt

AIM: To investigate the outcomes of adaptive conjunctival flap advancement surgical techniques with or without scleral graft for patients undergoing revision surgery after ***: This retrospective study included 28 eyes of 28 subjects from December 2015 to April 2018. A group of 15 eyes underwent conjunctival advancement only while the other 13 eyes did conjunctival advancement with partial thickness scleral graft. In both study groups, we considered the intraocular pressure(IOP) as our primary outcome and visual acuity(VA) as our secondary outcome. Both were assessed pre-and post-operatively till the last followup possible point. Additionally, we classified the patients according to complete and qualified success ***: The mean age of the conjunctival advancement group was 36.87±19.25 y, while it was 44.08±18.04 in the other group. In both study groups, the mean IOP significantly increased after revision surgery at 1, 2, 3 mo and the last follow-up visit when compared to prior the surgery(P<0.001). Moreover, VA was significantly improved(P=0.03) in the final follow-up for both surgical techniques. When we compared the change from baseline in both groups, there was no significant difference between IOP improvement in 1 mo(P=0.263), while the difference was significant in 2 mo(P=0.03), 3 mo(P=0.02) and in the final follow-up visit postoperatively. However, this difference was not significant regarding VA(P=0.5).CONCLUSION: The both adaptive techniques of conjunctival advancement and conjunctival advancement with scleral graft are effective for treating patients with lateonset hypotony. Yet, more prospective studies are needed to assert upon these results.

关键词： trabeculectomy scleral melting revision surgery hypotony maculopathy

Influence of Recycling Waste Glass as Fine Aggregate on the Concrete Properties

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Renewable Materials 2023年第6期11卷 2925-2940页

作者： Rafal A.Hadi Suhad M.Abd Hadee Mohammed Najm shaker Qaidi Moutaz Mustafa A.Eldirderi Khaled mohamed Khedher Department of Civil Engineering Bilad Alrafidain University CollegeDiyala32001Iraq Department of Civil Engineering College of EngineeringUniversity of DiyalaDiyala32001Iraq Department of Civil Engineering Zakir Husain Engineering CollegeAligarh Muslim UniversityAligarh202002India Department of Civil Engineering College of EngineeringUniversity of DuhokDuhok42001Iraq Department of Civil Engineering College of EngineeringNawroz UniversityDuhok42001Iraq Department of Chemical Engineering College of EngineeringKing Khalid UniversityAbha61421Saudi Arabia Department of Civil Engineering College of EngineeringKing Khalid UniversityAbha61421Saudi Arabia Department of Civil Engineering High Institute of Technological StudiesMrezgua University CampusNabeul8000Tunisia

Recent years have witnessed an increase in the quantity of waste glass(WG)across the *** the fine aggregate with WG is one of the steps toward preserving the natural resources of the environment and creating low-cost *** present study is concerned with replacing fine aggregates with glass powder(GP)at(0%,15%,30%,and 50%).It has studied the fresh and hardened properties(compressive strength,tensile strength,hardened density,and slump)for all the mentioned percent *** findings have shown that all mixtures containing GP gave acceptable slump results within the design limits(2–5 cm)according to ACI standard *** has been observed that increasing the proportion of GP led to a decrease in the weight of ***,replacing GP with sand by 30%has led to an increase in the compressive strength by about 2.4%and 12.45%,and the tensile strength by about 2.5%and 26.54%at 7-and 28-d,respectively in comparison to normal concrete.

关键词： Sustainable concrete glass powder fine aggregate partial replacement

Validation of prognostic indices in Egyptian Budd-Chiari syndrome patients: A single-center study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2017年第4期23卷 629-637页

作者： Mohammad Sakr Sara M Abdelhakam Soheir A Elsayed Enas H Allam Amir M Farid Waleed Abdelmoaty Azza M Hassan mohamed shaker mohamed El-Gharib Ahmed Eldorry Department of Tropical Medicine Faculty of MedicineAin Shams University Department of Community Environmental and Occupational MedicineFaculty of MedicineAin Shams University Department of Radiodiagnosis and Interventional Radiology Faculty of MedicineAin Shams University

AIMTo compare predictive ability of Budd-Chiari syndrome (BCS) prognostic indices (PIs) for one-year survival and Transjugular intrahepatic portosystemic shunt (TIPS) *** retrospective study enrolled 194 Egyptian patients with primary BCS who presented to the Budd-Chiari Study Group of Ain Shams University Hospital. Calculation of the available PIs was performed using Child-Pugh and model for end-stage liver disease scores, BCS-specific PIs (Clichy, New Clichy and Rotterdam) for all patients, and BCS-TIPS PI only for patients who underwent TIPS. The overall one-year survival rate and the one-year shunt patency rate for TIPS were *** overall one-year survival rate was 69.6%, and the New Clichy PI revealed the best validity for its prediction at a cut-off value of 3.75, with sensitivity and specificity of 78% and 73.3%, respectively [area under receiver operating characteristic curve (AUC) = 0.806]. The one-year survival rate post-TIPS was 89.7%, and the BCS-TIPS score demonstrated validity for its prediction at a cut-off value of 3.92 (sensitivity and specificity were 71.4% and 64.5%, respectively) (AUC = 0.715). Logistic regression analysis revealed that the New Clichy PI (P = 0.030), high serum total bilirubin (P = 0.047) and low albumin (P < 0.001) were independent factors for predicting mortality within one year. The one-year shunt patency rate in TIPS was 80.2%, and none of the PIs exhibited significant validity for its *** New Clichy score could independently predict the one-year survival in Egyptian BCS patients.

关键词： Budd-Chiari syndrome Prognostic indices New Clichy score One-year survival Transjugular intrahepatic portosystemic shunt

Solution-processed quantum dot SnO_(2) as an interfacial electron transporter for stable fully-air-fabricated metal-free perovskite solar cells

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materiomics 2022年第6期8卷 1172-1183页

作者： Rabie M.Youssef A.M.S.Salem Ahmed Shawky shaker Ebrahim Moataz Soliman mohamed S.A.Abdel-Mottaleb Said M.El-Sheikh Nanostructured Materials and Nanotechnology Department Advanced Materials InstituteCentral Metallurgical Research and Development Institute(CMRDI)P.O.Box:87HelwanCairo11421Egypt Nano-Photochemistry and Solar Chemistry Labs. Department of ChemistryFaculty of ScienceAin Shams UniversityAbbassiaCairoEgypt Department of Materials Science Institute of Graduate Studies and ResearchAlexandria UniversityEgypt

Perovskite solar cells could strongly compete with the silicon solar cells in the market soon as illustrated in recent *** this work,promising and stable metal-free perovskite solar cells(PSCs)has been successfully fabricated using an inorganic SnO_(2)/Quantum dot SnO_(2)(QD-SnO_(2))double layer as an efficient electron transport layer via a low-temperature solution *** fully-air fabricated PSCs in the form of FTO/SnO_(2)/QD-SnO_(2)/CH3NH3PbI3/Carbon were tested at different annealed QD-SnO_(2) between 300 and 500℃.The as-prepared QD-SnO_(2) and the fabricated devices are characterized by various techniques,including XRD,XPS,HR-TEM,FE-SEM,UVeviseNIR spectroscopy,PL,and solar *** prepared QD-SnO_(2) at 300℃ has shown well-ordered nanoparticles of 5.6 nm in diameter with superior carrier density(1.5×10^(15) cm^(-3))and highest carrier mobility(64.1 cm^(2)·V^(-1)·s^(-1)),accelerating the carriers separation process within the *** best devices demonstrated a maximum power conversion effi-ciency(PCE)of 11.7%,VOC 0.81 V,JSC 19.5 mA·cm^(-2),and FF 74%.The presence of an interfacial layer of QDSnO_(2) over the blocking SnO_(2) upsurges the band gaps alignment and accelerates the carriers extraction rate affecting the performance of the fabricated perovskite ***,the optimized fabricated devices revealed a shelf stability-life of four months in humid air(40%-50%)with>83%of its initial *** simple synthetic approach can develop the opportunities to transfer the cell from the lab to the market,which will be compatible with large-scale production.

关键词： Solution-processed nanomaterials Perovskite solar cells Electron transport layer Thin film Quantum Dot-SnO_(2)

Outcome of non surgical hepatic decompression procedures in Egyptian patients with Budd-Chiari

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2011年第7期17卷 906-913页

作者： Ahmed Eldorry Eman Barakat Heba Abdella Sara Abdelhakam mohamed shaker Amr Hamed Mohammad Sakr Department of Radiodi-agnosis and Interventional Radiology Faculty of Medicine AinShams University Department of Tropical Medicine Faculty of Medicine Ain Shams University

AIM: To evaluate outcome of patients with Budd-Chiari syndrome after balloon angioplasty ± stenting or transjugular intrahepatic portosystemic shunt (TIPS). METHODS: Twenty five patients with Budd-Chiari syndrome admitted to Ain Shams University Hospitals, Tropical Medicine Department were included. Twelve patients (48%) with short segment occlusion were candidates for angioplasty; with stenting in ten cases and without stenting in two. Thirteen patients (52%) had Transjugular Intrahepatic Portosystemic Shunt. Patients were followed up for 12-32 mo. RESULTS: Patency rate in patients who underwent angioplasty ± stenting was 83.3% at one year and at end of follow up. The need of revision was 41.6% with one year survival of 100%, dropped to 91.6% at end of follow up. In patients who had Transjugular Intrahepatic Portosystemic Shunt, patency rate was 92.3% at one year, dropped to 84.6% at end of follow up. The need of revision was 38.4% with one year and end of follow up survival of 100%. Patients with patent shunts showed marked improvement compared to those with occluded shunts. CONCLUSION: Morbidity and mortality following angioplasty ± stenting and TIPS are low with satisfactory outcome. Proper patient selection and management of shunt dysfunction are crucial in improvement.

关键词： Angioplasty Stenting Transjugular Intrahepatic portosystemic shunt Patency rate

Combined Action of Copper with IAA on Individual Amino Acids and Microelement in Pods of Two Broad Bean Cultivars

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Plant Sciences 2019年第4期10卷 670-697页

作者： Hamdia Mahmoud Abd El-Samad mohamed Abdo Kheder Shaddad Khloud Nagy shaker Botany Department and Microbiology Faculty of Science Minia University El-Minia Egypt Botany Department Faculty of Science Assiut University Assiut Egypt

It is worthy to mention that the two broad bean cultivars displayed a surprising situation during the fruiting stage of growth. The absolute amount of pods yield was higher in cv. Assiut 125 than in cv. Assiut 84. This situation was in contrast with that in the vegetative stage, where cv. Assiut 84 produced greater vegetative growth than cv. Assiut 125. Although the cv. Assiut 84 was less affected by the highest dose of copper, the cv. Assiut 125 was greatly affected by this dose. However, another surprising situation was recorded when the absolute values of fresh and dry matter of cv. Assiut 125 were much higher than cv. Assiut 84 at any used copper concentration. The fresh matters of the pods of cv. Assiut 84 and cv. Assiut 125 were 7.24 and 10.16 gm at the level of control and 6.69 and 7.59 gm at the level of 350 ppm Cu, respectively. Their dry matters were 1.99 and 3.52 gm at the level of control and 1.77 and 2.13 gm at the level of 350 ppm Cu2+ in cv. Assiut 84 and cv. Assiut 125, respectively. This contradiction was also extended when these copper-affected cultivars were sprayed by IAA. The cv. Assiut 84 responded slightly to IAA treatment. On the other hand, a considerable increase in the dry matter yield was recorded in the pods of cv. Assiut 125 at any used level of copper when compared to the non-sprayed plants treated by the same copper concentration. At the level of 350 ppm Cu2+ , the pod yield was 2-fold that of plants treated only by 350 ppm Cu2+ , without IAA spraying. Thus, even IAA behaved differently in its effect on the crop yield of the two tested broad bean cultivars. There are big and surprising variations in the accumulation of microelements and heavy metals in pods among the two broad bean genotypes, whatever the treatments used. These variations seemed to be complicated which might need further studies. The concentration of amino acids and their individuals also varied among the two cultivars;they increased in cv. Assiut 84 and decreased in

关键词： Synergistic Effect Amino Acids Microelement Broad Bean Cultivars

P53 rs1042522 and CD95 rs1800682 genetic variations in HCV-4a response to antiviral therapy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Genes & Diseases 2015年第2期2卷 197-210页

作者： Ahmed A.Abd-Rabou Emad F.Eskander Mervat S.mohamed Shaymaa M.M.Yahya Ashraf El Sherbini Olfat G.shaker Hormones Department Medical Research DivisionNational Research CentreCairo 12622Egypt Chemistry Department Biochemistry SpecialtyFaculty of ScienceCairo UniversityEgypt Internal Medicine Department Medical Research DivisionNational Research CentreCairoEgypt Medical Biochemistry and Molecular Biology Department Faculty of MedicineCairo UniversityEgypt

Current estimates indicate that the hepatitis C(HCV)is the leading cause of mortality around the world,with infection rates steadily increasing in *** dual therapy for this silent epidemic with pegylated-interferon-a2b/ribavirin has markedly improved the success rates in genotype-4 *** was reported that apoptosis plays a vital mechanistic role in limiting viral replication.P53,a key regulator of apoptosis,induces CD95 gene expression and subsequently initiates apoptotic cascade to be *** current study examined the impact of P53 rs1042522 and CD95 rs1800682 polymorphisms on the treatment *** groups of 240 volunteers were enrolled in this study;86 in sustained virological responders group,74 in non-responders group,and 80 in control *** patients had HCV genotype-4a and were interferon treatment naı¨*** of HCV-RNA by qRT-PCR and histological scores were performed for all *** addition,genotyping of HCV-RNA,P53 rs1042522 Arg/Pro and CD95 rs1800682 A/G polymorphisms were investigated in all *** was resulted that P53 Pro/Pro homozygous genotype has high significant increase,while CD95 A/A homozygous genotype has high significant decrease when comparing non-responders with ***,it was concluded that Pro variant of P53 rs1042522 may be used as a genetic predictor for non-responsiveness,while A/A variant of CD95 rs1800682 may be used as a sensitive biomarker for responsiveness to antiviral therapy of HCV genotype-4a *** addition,low prolactin,high total testosterone,and high GH levels may provide promising biomarkers for early prediction of the response when associated with these genetic polymorphisms.

关键词： CD95 rs1800682 HCV gentotype-4a P53 rs1042522 Response SNPs