检索结果-南通市图书馆

scheduling Multi-Mode Resource-Constrained Projects Using Heuristic Rules Under Uncertainty Environment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第1期70卷 847-874页

作者： mohamed Abdel-Basset Ahmed sleem asmaa Atef Yunyoung Nam mohamed Abouhawwash Faculty of Computers and Informatics Zagazig UniversityZagazig44519Egypt Department of Computer science and Engineering Soonchunhyang UniversityAsan31538Korea Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast Lansing48824MIUSA

Project scheduling is a key objective of many models and is the proposed method for project planning and *** scheduling problems depend on precedence relationships and resource constraints,in addition to some other limitations for achieving a subset of *** scheduling problems are dependent on many limitations,including limitations of precedence relationships,resource constraints,and some other limitations for achieving a subset of *** project scheduling models consider all information about the scheduling problem such as activity durations and precedence relationships information resources available and required,which are known and stable during the implementation *** concept of deterministic project scheduling conflicts with real situations,in which in many cases,some data on the activity’s durations of the project and the degree of availability of resources change or may have different modes and strategies during the process of project implementation for dealing with multi-mode conditions surrounded by projects and their activity *** the multi-mode resource-constrained project problem is an optimization problem whose minimum project duration subject to the availability of resources is of particular interest to *** use the multi-mode resource allocation and schedulingmodel that takes into account the dynamicity features of all parameters,that is,the scheduling process must be flexible to dynamic environment *** this paper,we propose five priority heuristic rules for scheduling multi-mode resource-constrained projects under dynamicity features for more realistic situations,in which we apply the proposed heuristic rules(PHR)for scheduling multi-mode resource-constrained *** projects are considered test problems for the *** obtained results rendered by these priority rules for the test problems are compared by the results obtained from 10 well-known heuristics rules rendered for

关键词： Constrained resource scheduling multi-mode durations dynamic scheduling resource allocation heuristic rules

Egyptian heavy vacuum gas oil hydrotreating over Co-Mo/CNT and Co-Mo/γ-Al2O3 catalysts

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

燃料化学学报 2016年第7期44卷 853-861页

作者： W.Ahmed Hoda,s.Ahmed H.s.El-sheshtawy Nadia,A.mohamed asmaa,I.Zahran Egyptian Petroleum Research Institute 1Aahmed El-Zomor st.Naser city 11727CairoEgypt Ain-shams University for Girls Roqqsy SquireCairoEgypt

The catalytic activity of CoMos /CNT towards the Egyptian heavy vacuum gas oil hydrotreating was studied. The delivered CNT was functionalized with 6 mol /L HNO_3. The CNT were loaded with 12% MoO_3( by weight) and 0.7 Co /Mo atomic ratio with impregnation methods. The γ-Al_2O_3 catalyst was also prepared by impregnation method to compare both catalysts *** analysis tools such XRD,Raman spectroscopy,TEM,and BET were used to characterize the catalysts. The autoclave reactor was used to operate the hydrotreating experiments. The hydrotreating reactions were tested at various operating conditions of temperature 325-375 ℃,pressure 2-6 MPa,time 2-6 h,and catalyst /oil ratio( by weight) of 1 ∶75,1 ∶33 and 1 ∶10. The results revealed that the CoMos /CNT was highly efficient for the hydrotreating more than the CoMos /γ-Al_2O_3. Also, the hydrodesulfurization( HDs) increased with increasing catalyst /oil ratio. Additionally,results showed that the optimum condition was temperature 350℃,pressure 4 MPa,catalyst /oil ratio of 1 ∶75 for 2 h. Furthermore,even at low CoMos /CNT catalyst /oil ratio of 1 ∶75,an acceptable HDs of 77.1% was achieved.

关键词： hydrotreatment hydrodesulfurization carbon nanotube heavy vacuum gas oil(HVGO)

Assessment of plant diversity of endemic species of the saharo-Arabian region in Egypt

在线全文

学校读者我要写书评

暂无评论

Journal of Arid Land 2024年第7期16卷 1000-1021,I0002-I0044页

作者： asmaa s ABO HATAB Yassin M AL-sODANY Kamal H sHALTOUT soliman A HAROUN mohamed M EL-KHALAFY Botany and Microbiology Department Faculty of ScienceKafrelsheikh UniversityKafrelsheikh 33511Egypt Botany Department Faculty of ScienceTanta UniversityTanta 31527Egypt

savanna, semi-deserts, and hot deserts characterize the saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the sudano-Zambezian region belonging to the Paleotropical Kingdom and the Mediterranean and Irano-Turanian regions included in the Holarctic Kingdom, share a large portion of their flora with the saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. Hence, a preliminary list of 429 saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, south sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of sinai Peninsula, 53 taxa). sahara regional subzone(ss1) distributes all the 126 endemic species, Arabian regional subzone(ss2) owns 79 taxa, and Nubo-sindian subzone(ss3) distributes only 14 endemics. seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINsPAN) to the saharo-Arabian endemic sp

关键词： endemism phytogeographical regions saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINsPAN)

Liver stiffness as a predictor of hepatocellular carcinoma behavior in patients with hepatitis C related liver cirrhosis

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2020年第1期19卷 22-28页

作者： sameh A Lashen mohamed M Elshafei Fahmy H Hablass Eman A Alsayed asmaa A Hassan Department of Internal Medicine Faculty of MedicineUniversity of AlexandriaAlexandriaEgypt Department of Radiology Faculty of MedicineUniversity of AlexandriaAlexandriaEgypt Department of Biomedical Informatics and Medical statistics Medical Research InstituteUniversity of AlexandriaAlexandriaEgypt

Background: Risk strati cation and prognostication of hepatocellular carcinoma (HCC) help to improve patient outcome. Herein we investigated the role of liver stiffness measurement (LsM) in the prediction of HCC behavior. Methods: Totally 121 na ve patients with HCC were included. HCC radiological evaluation and staging were done. LsM was measured using virtual touch quanti cation. Patients were divided into early to intermediate HCC (BCLC-0, A and B) and late HCC (BCLCC and D). HCC was treated according to the BCLC stage. HCC recurrence-free interval was estimated. Results: The mean LsM inside the tumor was signi cantly lower than the peri-tumoral area and the cirrhotic non-cancerous liver parts (Ps stage, the mean LsM inside the tumor and in the peri-tumoral tissue was lower than the corresponding values in the early to intermediate HCCs stage (PsM inside the tumor and in the peri-tumoral tissue negatively correlated with serum AFP, tumor vascular invasion, and stage (Ps directly correlated to LsM inside the tumor and inversely to LsM in cirrhotic non tumorous liver part. Kaplan-Meier analysis showed that the recurrence-free interval was signi cantly longer in patients with LsM inside the tumor of ≥1.25m/s compared to those with LsM inside the tumor ofs. Conclusions: LsM can serve as a potential non-invasive predictor for HCC clinical behavior and the recurrence-free interval following loco-regional treatments.

关键词： Fibrosis Hepatitis C Hepatocellular carcinoma Point shear wave Liver cirrhosis

Effect of cholesterol-loaded cyclodextrin enriched extenders on the quality of pre- frozen and frozen buffalo semen

在线全文

学校读者我要写书评

暂无评论

Asian pacific Journal of Reproduction 2022年第3期11卷 146-152页

作者： asmaa A.Mostafa mohamed s.El-Belely sayed T.Ismail Reda I.El-sheshtawy mohamed I.shahba Abassia Frozen semen Center General Organization for Veterinary ServicesCairoEgypt Department of Theriogenology Faculty of Veterinary MedicineCairo UniversityGizaEgypt Department of Animal Reproduction and Artificial Insemination National Research CentreDokkiGizaEgypt

Objective:To investigate the effects of non-permeable cryoprotectant,cholesterol-loaded cyclodextrin,when added at different concentrations into cooled and frozen-thawed semen extended with Tris-citrate-fructose egg yolk glycerol and lecithin-based ***:A total of 40 ejaculates from four buffalo bulls were collected using artificial *** were extended with one of Tris-citrate-fructose egg yolk glycerol and lecithin-based extenders which contained different concentrations[0(control),0.75,1.50,2.25 and 3.00 mg/mL]of cholesterol-loaded *** extended semen samples were cooled to 5曟and then frozen slowly to-196曟in 0.25 mL ministraws before being stored in liquid nitrogen pending its *** motility,live sperm,normal sperm morphology,sperm membrane integrity and acrosome morphology were ***:supplementation of cholesterol-loaded cyclodextrin improved progressive motility,viability,morphology and acrosome as well as plasma membrane integrities at 1.50-2.25 mg/mL depending upon types of used extenders and stages of pre-and post-freezing process(Pst concentration was 1.50 mg/mL at pre-freeze stage and 2.25 mg/mL at ***,greater concentration(3.00 mg/mL)of cholesterol-loaded cyclodextrin had a detrimental effect compared to the control group with the two evaluated extenders(Psions:Cholesterol-loaded cyclodextrin supplementation at 1.50-2.25 mg/mL concentration could improve pre-frozen and post-thawed buffalo sperm *** most suitable concentration is 1.50 mg/mL at pre-freeze stage and 2.25 mg/mL at post-freezing.

关键词： Buffalo semen Tris Cooling Cryopreservation Cholesterol-loaded cyclodextrin semen evaluation

Impact of replacing egg yolk with lecithin on quality of pre-freeze and post-thaw buffalo spermatozoa

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian pacific Journal of Reproduction 2018年第6期7卷 254-260页

作者： asmaa A.Mostafa mohamed.s.El-Belely sayed.T.Ismail Reda.I.El-sheshtawy mohamed I.shahba Abassia Frozen semen Center General Organization for Veterinary ServicesCairoEgypt Department of Theriogenology Faculty of Veterinary MedicineCairo UniversityGizaEgypt Animal Reproduction and Artificial Insemination Department National Research CentreDokkiGizaEgypt

Objective:To estimate the result of egg yolk replacement with alternative cryopreservatives such as plant-derived lecithin from soybean on sperm quality parameters pre and post freezing in buffalo ***: The control cryopreservation extender was tris-citric acid-fructose-egg yolk-glycerol (TCFYG) diluent. semen samples were extended gradually 1:10 with TCFYG control extender and tris-citric acid-fructose-glycerol (TCFG) extender plus variable concentrations of soybean lecithin (0.5%, 1.0%, 1.5%, 2.0%, 2.5% and 3.0%) to ensure 60 million active spermatozoa/mL of the extended semen. The diluted semen samples were refrigerated slowly (roughly for 2 h) up to 5℃ and equilibrated for 2 h. semen was filled into 0.25 mL polyvinyl French straws (IMV, France). After equilibration period, the straws were placed horizontally on a rack and frozen in a vapor 4 cm above liquid nitrogen for 10 min and were then dipped stored in liquid nitrogen at -196℃. Results:The respective overall percentages of forward motile spermatozoa, live spermatozoa, morphologically normal spermatozoa, acrosome integrity and hypo-osmotic swelling reactivity observed primarily in fresh semen, after equilibration (pre-freeze stage) and post freezing (post-thaw stage) in TCFYG (control) extended semen declined progressively and statically (Pse periods of study. Pre-freezing stage: replacement of egg yolk into TCFG with soybean lecithin at concentrations of 1.0% and 1.5% significantly (Psome and membrane integrity %), meanwhile it had significantly (Pspermatozoa to the lowest value compared to control TCFYG and to some other concentrations in use. Post-thaw stage: the replacement of egg yolk with 1.0% soybean lecithin (sL) showed significantly (Psperm progressive motility compared to 1.5% sL and TCFYG control. These values were significantly (P<0.01) higher t

关键词： Buffalo semen Preservation soybean lecithin

series solution of a natural convection flow for a Carreau fluid in a vertical channel with peristalsis

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 Hydrodynamics 2015年第6期27卷 969-979页

作者： ABD ELMABOUD Y. MEKHEIMER Kh.s. mohamed mohamed s. Mathematics Department Faculty of Science and ArtsKhulaisUniversity Of Jeddah Mathematics Department Faculty of ScienceAl-Azhar University(Assiut Branch) Mathematics Department Faculty of ScienceTaif University Hawia Mathematics Department Faculty of ScienceAl-Azhar University

An analysis has been achieved to study the natural convection of a non-Newtonian fluid （namely a Carreau fluid） in a vertical channel with rhythmically contracting walls. The Navier-stokes and the energy equations are reduced to a system of non- linear PDE by using the long wavelength approximation. The optimal homotopy analysis method （OHAM） is introduced to obtain the exact solutions for velocity and temperature fields. The convergence of the obtained OHAM solution is discussed explicitly. Numerical calculations are carried out for the pressure rise and the features of the flow and temperature characteristics are analyzed by plotting graphs and discussed in detail.

关键词： homotopy analysis method (HAM) peristaltic transport carreau fluid heat transfer natural convection flow

Dynamic Interaction Analysis of Coupled Axial-Torsional-Lateral Mechanical Vibrations in Rotary Drilling systems

在线全文

学校读者我要写书评

暂无评论

structural Durability & Health Monitoring 2025年第1期19卷 77-103页

作者： sabrina Meddah sid Ahmed Tadjer Abdelhakim Idir Kong Fah Tee mohamed Zinelabidine Doghmane Madjid Kidouche Applied Automation Laboratory Faculty of Hydrocarbons and ChemistryUniversity of BoumerdesBoumerdes35000Algeria Institute of Electrical and Electronic Engineering(IGEE) University of BoumerdesBoumerdes35000Algeria Laboratory of the Electrification of Industrial Enterprises University of BoumerdesBoumerdes35000Algeria Electrical Engineering Department Mohamed Boudiaf University of M’silaM’sila28000Algeria Department of Civil and Environmental Engineering King Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Interdisciplinary Research Center for Construction and Building Materials King Fahd University of Petroleum&Minerals(KFUPM)Dhahran31261Saudi Arabia

Maintaining the integrity and longevity of structures is essential in many industries,such as aerospace,nuclear,and *** achieve the cost-effectiveness of large-scale systems in petroleum drilling,a strong emphasis on structural durability and monitoring is *** study focuses on the mechanical vibrations that occur in rotary drilling systems,which have a substantial impact on the structural integrity of drilling *** study speciﬁcally investigates axial,torsional,and lateral vibrations,which might lead to negative consequences such as bit-bounce,chaotic whirling,and high-frequency *** events not only hinder the efﬁciency of drilling but also lead to exhaustion and harm to the system’s components since they are difﬁcult to be detected and controlled in real *** study investigates the dynamic interactions of these vibrations,speciﬁcally in their high-frequency modes,usingﬁeld data obtained from measurement while ***ﬁndings have demonstrated the effect of strong coupling between the high-frequency modes of these vibrations on drilling sys-tem *** obtained results highlight the importance of considering the interconnected impacts of these vibrations when designing and implementing robust control ***,integrating these compo-nents can increase the durability of drill bits and drill strings,as well as improve the ability to monitor and detect ***,by exploiting theseﬁndings,the assessment of structural resilience in rotary drilling systems can be ***,the study demonstrates the capacity of structural health monitoring to improve the quality,dependability,and efﬁciency of rotary drilling systems in the petroleum industry.

关键词： Rotary drilling systems mechanical vibrations structural durability dynamic interaction analysis ﬁeld data analysis

Effect of butylated hydroxytoluene on quality of pre-frozen and frozen buffalo semen

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian pacific Journal of Reproduction 2019年第1期8卷 20-24页

Objective: To clarify the antioxidant effect of butylated hydroxytoulene (BHT) at different concentrations on cooled and post frozen semen diluted in tris-citrate-fructose egg yolk glycerol and lecithin -based extenders. Methods: Forty ejaculates were harvested from four buffalo bulls by means of the artificial vagina. Ejaculated semen samples were diluted with each of the tris citrate-fructose egg yolk glycerol and lecithin-based extender diluents. The semen samples diluted with each of the two extenders were added to pre-warmed dried test tubes containing BHT (prepared in ethanol) to get concentrations at 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mM/mL BHT. These ingredients were put at 37 ℃ for 5 min to allow the proper BHT spermatozoal permeation. The diluted semen samples were cooled to 5 ℃ and then frozen to -196 ℃ in 0.25 mL ministraws before dipping in liquid nitrogen pending its evaluation. sperm motility, viability, morphology, intact acrosome and membrane integrity were tested. Visual motility was tested using a high power ordinary microscope (at 400 × ) with closed circuit television, and sperm concentration was tested using Neubauer haemocytometer and abnormality % using eosin-nigrosin stain. spermatozoal membrane integrity was tested using the hypo-osmotic swelling test. The sperm with swollen twisting tail was normally intact. sperm acrosomal integrity % was tested as mentioned by Watson. Results: Addition of BHT improved (Pssive motility, viability, morphology and acrosome as well as plasma membrane integrities at 0.5-2.0 mM/mL depending upon types of used extenders and stages of pre-and post-freezing process. Higher levels of 2.5 and 3.0 mM/mL BHT had a deteriorating (Psult if compared to the control and all extenders assayed. Conclusions: BHT addition at lower concentration can improve pre-frozen and post-thawed buffalo sperm quality.

关键词： Butylated hydroxytoulene Lecithin Egg yolk Buffalo semen Cryopreservation