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Prediction of new perforation intervals in a depleted reservoir to achieve the maximum productivity: A case study of PNN logging in a cased-well of an Iranian oil reservoir

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Petroleum 2020年第2期6卷 170-176页

作者： Saeed Zaker shahab mohamadi nafchi Mahdi Rastegarnia Soheila Bagheri Ali Sanati Amir Naghibi Islamic Azad University Science and Research BranchTehranIran Islamic Azad University Central BranchTehranIran Head of Petrophysics Section Petro Pardazesh Aria CompanyTehranIran Senior Petrophysicist OTS CompanyTehranIran School of Petrochemical and Petroleum Engineering Hakim Sabzevari UniversitySabzevarIran Senior Petrophysicist Iranian Central Oil Field CompanyTehranIran

Pulsed neutron-neutron(PNN)logging is based on emitting neutrons into the near-wellbore zone and computing the neutron count decay due to scattering and *** main application of this logging tool is to determine the current oil saturation and to detect channeling in perforated and non-perforated intervals behind the *** interpretation of the results obtained from PNN logging enables engineers to predict new perforation intervals in depleted *** study examines the application of PNN logging in a well located in one of Iranian oil *** interpretation procedure is described step by *** principle of the PNN logging and the specifications of the tool are discussed and the applications of PNN logging in evaluation of oil saturation,identification of water flooded zones and prediction of potential perforating zones are *** is also investigated between all layers,good and poor oil zones are characterized based on the calculated oil saturations and new perforation intervals are suggested with the aim to boost oil production from the *** results of this study show that zones 1 to 5 having low oil saturations,are interpreted as depleted oil *** 6 to 8 are interpreted as good oil zones having high potential to produce *** 9 is interpreted as a water zone.

关键词： Pulse neutron-neutron(PNN)logging Sigma value Remaining oil saturation Conventional logging Perforation intervals Depleted reservoir

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Single fiber colorless symmetric WDM-PON architecture using time interleaved remodulation technique for mitigating Rayleigh backscattering resilience

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Optoelectronics Letters 2013年第1期9卷 38-41页

作者： Muhammad Idrees Afridi 张杰赵永利 Abdul Latif shahab Ahmed Niazi State Key Laboratory of Information Photonics and Optical Communications School of Electronic Engineering Beijing University of Posts and Telecommunications

A time interleaved differential phase shift keying (DPSK) remodulation technique is proposed to mitigate the effect of Rayleigh backscattering (RBS)-induced noise in a single fiber colorless wavelength-division-multiplexing passive optical network (WDM-PON). In order to achieve a cost effective optical network unit (ONU) solution without dedicated laser sources for upstream signals to provide optimum symmetric capacity in a colorless WDM-PON, remodulation becomes the core attraction. Also as the performance of colorless WDM-PON systems suffers from the transmission impairments due to RBS, it is mitigated by using this remodulation scheme. Simulation results show that downstream and upstream signals achieve the error-free performance at 10 Gbit/s with negligible penalty, and enhance the tolerance to RBS-induced noise over a 25 km single-mode fiber.

关键词： WDM-PON 调制技术瑞利后向散射单纤维无色对称交错时间

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Fe_3O_4@MCM-48–SO_3H:合成苯并[f]色烯并[2,3-d]嘧啶酮的高效、可磁性分离纳米催化剂(英文)

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催化学报 2015年第4期36卷 572-578页

作者： Hassan Kefayati Mostafa Golshekan shahab Shariati Mahsa Bagheri Department of Chemistry Rasht Branch Islamic Azad University Rash t Iran Young Researchers and Elite Club Rasht Branch Islamic Azad University Rasht Iran

Sulfonic acid groups were grafted onto three different types of synthesized magnetic nanoparticles, namely Fe3O4, Fe3O4@SiO2, and Fe3O4@MCM-48. The sulfonic acid-functionalized nanoparticles were evaluated as catalysts for the synthesis of 5-aryl-1H-benzo[f]chromeno[2,3-d]pyrimidine-2,4(3H,5H)-dione derivatives in terms of activity and recyclability. Their catalytic activities were compared with that of the homogeneous acid catalyst 1-methylimidazolium hydrogen sulfate([HMIm][HSO4]). The activity of Fe3O4@MCM-48–SO3H was comparable to those of the other heter-ogeneous and homogeneous catalysts.

关键词： MCM-48 Fe3O4 纳米催化剂嘧啶酮合成磁性纳米颗粒均相催化剂分离

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The importance of visualization of appendix on abdominal ultrasound for the diagnosis of appendicitis in children: A quality assessment review

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World Journal of Emergency Medicine 2020年第3期11卷 140-144页

作者： Muhammad Akhter Hamid Ruqiya Afroz Uqba Nawaz Ahmed Aneela Bawani Dilnasheen Khan Rabia shahab Asim Salim Scarborough Health Network TorontoONCanada Department of Paediatrics University of TorontoONCanada St.Michael's Hospital TorontoONCanada Grand River Hospital KitchenerONCanada Brantford General Hospital BrantfordONCanada

BACKGROUND:Ultrasound has the first line investigation role in the diagnosis of acute appendicitis in *** purpose of this study was to perform a quality assessment review on the visualization rate of appendix on ultrasound in children in the community hospital ***:A retrospective chart review of the abdominal ultrasound findings for the visualization of the appendix was performed on paediatric patients ranging from 5 to 18 *** were collected from the two community hospitals of Toronto by using hospital electronic medical record for the ultrasound findings in patients presented with abdominal ***:Data from two community hospitals indicated visualization rate of the appendix as 11.0%and 23.2%for site 1 and site 2 *** cases where the ultrasound was repeated the visualization rate remains the same.A two-proportion z-test was performed to find whether the visualization of appendix increases the likelihood of diagnosing *** results revealed that the visualization of an appendix(P=0.52),significantly improved the diagnosis of appendicitis(z=34,P<0.001).CONCLUSION:Visualization of an appendix on ultrasound increases the likelihood of correctly diagnosing *** our study,we found low visualization rate of appendix on ultrasound that could be the result of many factors that contribute towards the low visualization rate of an appendix on ***,the challenges in identifying appendix should be minimized to improve the visualization and diagnosis of appendicitis on ultrasound.

关键词： Abdominal ultrasound Visualization Importance Appendix Abdominal pain Acute appendicitis Children Paediatric population

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Optimization, Spectroscopic(FT-IR, Excited States, UV/Vis) Studies, FMO, ELF, LOL, QTAIM and NBO Analyses and Electronic Properties of Two New Pyrimidine Derivatives

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Chinese Journal of Structural Chemistry 2019年第10期38卷 1615-1639,1609页

作者： SIYAMAK shahab MASOOME Sheikhi LIUDMILA Filippovich ZANNA Ignatovich KONSTANTIN Laznev ALEXANDER Muravsky RADWAN Alnajjar SADEGH Kaviani Belarusian State University I SEI BSUMinskRepublic of Belarus Institute of Physical Organic Chemistry National Academy of Sciences of Belarus13 Surganov Str.Minsk 220072 Institute of Chemistry of New Materials National Academy of Sciences of Belarus36 Skarina Str.Minsk 220141 Young Researchers and Elite Club Gorgan BranchIslamic Azad UniversityGorganIran Department of Chemistry Faculty of ScienceUniversity of BenghaziBenghaziLibya Department of Chemistry University of Cape TownRondebosch 7701South Africa Department of Chemistry Ferdowsi University of MashhadMashhadIran

In the given research,the molecular structures of two new compounds,4-((E)-3-(dimethylamino)styryl)-6-((E)-4-(dimethylamino)styryl)pyrimidine-2-amine(PM-1)and N-(4-((E)-3-(dimethylamino)styryl)-6-((E)-4-(dimethylamino)styryl)pyrimidine-2-yl)-4,6-dichloro 1,3,5-1,3,5-triazin-2-amine(PM-2),have been studied with the use of density functional theory(DFT/B3LYP/MidiX)in dimethylformamide(DMF)for the first *** electronic spectra of the new compounds in a DMF solvent were carried out by temporally dependent density functional theory(TD-DFT)*** computed absorption spectral data of the title compounds are in good agreement with the experimental data,thus allowing an assignment of the UV/Vis *** equilibrium geometry,the HOMO and LUMO molecular orbitals,excitation energies,oscillator strengths and Natural Bond Orbital(NBO)analysis for the molecules have also been calculated and ***-IR spectra of the title molecules are recorded and *** electron location function(ELF),localized orbital locator(LOL)and quantum theory of atoms in molecules(QTAIM)analyses were also carried *** the basis of polyvinyl alcohol(PVA)and synthesized molecules,polarizer for UV/Vis region of the spectrum has been developed.

关键词： pyrimidine DFT UV/Vis spectrum TD-DFT polarization QTAIM analysis

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Co-existence generation of XG-PON and single carrier XLG-PON for ultra-high definition TV transmission with entirely passive optical plant

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Optoelectronics Letters 2013年第3期9卷 221-224页

作者： shahab Ahmad Niazi 张晓光席丽霞 Abid Munir Muhammad Idress State Key Laboratory of Information Photonics and Optical Communication Institute of Information Photonics and Optical Communication Beijing University of Posts and Telecommunications

International telecommunication union (ITU) recently has standardized ultra-high definition television (UHD-TV) with a resolution which is 16 times more than that of current high definition TV. Increasing the efficiency of video source coding or the capacity of transmission channels will be needed to deliver such programs by passive optical network (PON). In this paper, a complete passive co-existence of 10 Gbit-PON (XG-PON) and single carrier 40 Gbit-PON (XLG-PON) for overlay of UHD-TV distribution to 32 optical network units (ONUs) on broadcast basis is presented. The results show error free transmission performance with negligible power penalty over a 20 km bidirectional fiber.

关键词：高清电视传输信道单载波共存光学国际电信联盟无源光网络光网络单元

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Nonlinear Dynamic Response of a Fixed Offshore Platform Subjected to Underwater Explosion at Different Distances

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Journal of Marine Science and Application 2022年第4期21卷 168-176页

作者： Seyed shahab Emamzadeh Faculty of Civil Engineering Group Engineering DepartmentKharazimi UniversityTehranIran

In this paper,the dynamic response of a fixed offshore platform subjected to the underwater explosion(UNDEX)and probable events following it have been *** pressure load due to UNDEX in a specified depth has been applied with a model that considers the effect of blast bubble fluctuations into *** effect of water on the natural frequency and Fluid-Structure interaction has been modeled as equivalent added mass *** effect of explosion distance on platform response is *** this regard,three cases of near,medium,and far-distance explosions are *** a case study,a real fixed offshore jacket platform,installed in the Persian Gulf,has been *** the UNDEX pressure load is considered and other dynamic loads such as surface water waves and winds have been *** loads,live loads and hydrostatic pressure has been considered in the static case based on the design *** results indicated that in near-distance explosions,the UNDEX pressure load can locally damage parts of the platform that are located at the same level as that of explosive material and it can destabilize the *** the medium to far distance explosion,a very large base shear was applied to the platform because more elements were exposed to the UNDEX load compared to the near-distance ***,precautionary measures against UNDEX such as risk assessment according to design codes are *** a result of this,member strengthening against explosion may be required.

关键词： Dynamic response Water pressure Underwater explosion Added mass Offshore platforms

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Preventing Cloud Network from Spamming Attacks Using Cloudflare and KNN

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Computers, Materials & Continua 2023年第2期74卷 2641-2659页

作者： Muhammad Nadeem Ali Arshad Saman Riaz SyedaWajiha Zahra Muhammad Rashid shahab S.Band Amir Mosavi Department of Computer Science Abasyn UniversityIslamabad44000Pakistan Department of Computer Science National University of TechnologyIslamabad44000Pakistan Future Technology Research Center National Yunlin University of Science and TechnologyDouliuYunlin64002Taiwan Institute of Information Society University of Public ServiceBudapest1083Hungary John von Neumann Faculty of Informatics Obuda UniversityBudapestHungary Institute of Information Engineering Automation and MathematicsSlovak University of Technology in BratislavaSlovakia

Cloud computing is one of the most attractive and cost-saving models,which provides online services to *** computing allows the user to access data directly from any *** nowadays,cloud security is one of the biggest issues that *** types of malware are wreaking havoc on the *** on the cloud server are happening from both internal and external *** paper has developed a tool to prevent the cloud server from spamming *** an attacker attempts to use different spamming techniques on a cloud server,the attacker will be intercepted through two effective techniques:Cloudflare and K-nearest neighbors(KNN)*** will block those IP addresses that the attacker will use and prevent spamming ***,the KNN classifiers will determine which area the spammer belongs *** the end of the article,various prevention techniques for securing cloud servers will be discussed,a comparison will be made with different papers,a conclusion will be drawn based on different results.

关键词： Intrusion prevention system spamming KNN classification spam cyber security botnet

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Impact of sepsis and non-communicable diseases on prognostic models to predict the outcome of hospitalized chronic liver disease patients

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World Journal of Hepatology 2018年第12期10卷 944-955页

作者： Fakhar Ali Qazi Arisar shahab Abid Preet Ayoub Shaikh Safia Awan Section of Gastroenterology Department of MedicineFaculty Offices Buildingthe Aga Khan University Hospital

AIM To evaluate the impact of sepsis and non-communicable diseases(NCDs) on the outcome of decompensated chronic liver disease(CLD) *** this cross-sectional study, medical records of patients with CLD admitted to the Gastroenterology unit at the Aga Khan University Hospital were *** older than 18 years with decompensation of CLD(i.e., jaundice, ascites,encephalopathy, and/or upper gastrointestinal bleed) as the primary reason for admission were included, while those who were admitted for reasons other than decompensation of CLD were excluded. Each patient was followed for 6 wk after index admission to assess mortality, prolonged hospital stay(> 5 d), and early readmission(within 7 d).RESULTS A total of 399 patients were enrolled. The mean age was 54.3 ± 11.7 years and64.6%(n = 258) were male. Six-week mortality was 13%(n = 52). Prolonged hospital stay and readmission were present in 18%(n = 72) and 7%(n = 28) of patients, respectively. NCDs were found in 47.4%(n = 189) of patients. Acute kidney injury, sepsis, and non-ST elevation myocardial infarction were found in41%(n = 165), 17.5%(n = 70), and 1.75%(n = 7) of patients, respectively. Upon multivariate analysis, acute kidney injury, non-ST elevation myocardial infarction, sepsis, and coagulopathy were found to be statistically significant predictors of mortality. While chronic kidney disease(CKD), low albumin, and high Model for End-Stage Liver Disease(MELD)-Na score were found to be statistically significant predictors of morbidity. Addition of sepsis in conventionalMELD score predicted mortality even better than MELD-Na(area under receiver operating characteristic: 0.735 vs 0.686; P < 0.001). Among NCDs, CKD was found to increase morbidity *** Addition of sepsis improved the predictability of MELD score as a prognostic marker for mortality in patients with CLD. Presence of CKD increases the morbidity of patients with CLD.

关键词： Chronic liver disease Mortality Morbidity Prognostic factors Noncommunicable diseases Sepsis

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Traffic Queuing Management in the Internet of Things: An Optimized RED Algorithm Based Approach

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Computers, Materials & Continua 2021年第1期66卷 359-372页

作者： Abdul Waheed Naila Habib Khan Mahdi Zareei shahab Ul Islam Latif Jan Arif Iqbal Umar Ehab Mahmoud Mohamed Department of Information Technology Hazara UniversityMansehra21120Pakistan School of Electrical and Computer Engineering Seoul National UniversitySeoul08826Korea Department of Computer Science Institute of Management SciencesPeshawar25000Pakistan Tecnologico de Monterrey School of Engineering and SciencesZapopan45201Mexico Department of Computer Science IQRA National UniversityPeshawar25124Pakistan Department of Electrical Engineering University of Engineering TechnologyPeshawar25120Pakistan Electrical Engineering Department College of EngineeringPrince Sattam Bin Abdulaziz UniversityWadi Addwasir11991Saudi Arabia Electrical Engineering Department Faculty of EngineeringAswan UniversityAswan81542Egypt

Congestion control is one of the main obstacles in cyberspace *** in internet traffic may cause several problems;such as high packet hold-up,high packet dropping,and low packet *** the course of data transmission for various applications in the Internet of things,such problems are usually generated relative to the *** tackle such problems,this paper presents an analytical model using an optimized Random Early Detection(RED)algorithm-based approach for internet traffic *** validity of the proposed model is checked through extensive simulation-based *** analysis is observed for different functions on internet *** performance metrics are taken into consideration,namely,the possibility of packet loss,throughput,mean queue length and mean queue *** sets of experiments are observed with varying simulation *** experiments are thoroughly analyzed and the best packet dropping operation with minimum packet loss is identified using the proposed model.

关键词： Random early detection(RED) active queue management(AQM) quality of service(QOS) throughput

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