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An Ontology-Based Framework for Semi-Automatic Schema Integration

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Journal of Computer Science & Technology 2005年第6期20卷 788-796页

作者： Zille Huma Muhammad Jaffar-ur rehman Nadeem Iftikhar Muhammad Ali dinnah University Islamabad Pakistan

Currently, schema integration frameworks use approaches like rule-based, machine learning, etc. This paper presents an ontology-based wrapper-mediator framework that uses both the rule-based and machine learning strategies at the same time. The proposed framework uses global and local ontologies for resolving syntactic and semantic heterogeneity, and XML for interoperability. The concepts in the candidate schemas are merged on the basis of the similarity coefficient, which is calculated using the defined rules and the prior mappings stored in the case-base.

关键词： heterogeneous databases database integration database semantics rule-based processing machine learning

2D seismic interpretation of Sawan gas field integrated with petrophysical analysis:A case study from Lower Indus Basin,Pakistan

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能源地球科学(英文) 2023年第2期4卷 35-48页

作者： Abd ur rehman Khan Muhammad Amar Gul Rizwan Sarwar Awan Ashar Khan Khawaja Hasnain Iltaf Sibt.E Hassan Butt Oil and Gas Development Company IslamabadPakistan CAS Key Laboratory of Crust-Mantle Materials and Environments University of Science and Technology of ChinaHefei230026China School of Resources and Environmental Engineering Hefei University of TechnologyHefei230009China Water and Power Development Authority Pakistan Department of Earth&Environmental Sciences The University of Texas at ArlingtonUnited States Geological Survey of Pakistan LahorePakistan

The Lower Indus Basin is the leading hydrocarbon-bearing sedimentary basin in *** study has been conducted on the Sawan gas field located in the Lower Indus Basin,adjacent to a few other wellknown gas fields of Pakistan like Kadanwari,Qadirpur,and Miano gas *** research aims to present the spatial distribution and reservoir potential of the productive zones of the Lower Goru *** present study utilized various two-dimensional(2D)seismic lines and well-log data(Sawan-01 and Sawan-02)to investigate the structural and stratigraphic features of the *** stratigraphic layers are mildly deepening in the southeast *** 2D seismic interpretation of the research area identifies the existence of extensional remanents,i.e.,normal *** extensional structures are associated with horst and graben geometry that acts as a trapping mechanism for *** logs are used to identify the reservoir's diverse lithology and petrophysical *** results indicate fair to good effective porosities,low shale volume,and high hydrocarbon saturation(>55%),signifying good reservoir potential in C interval of the Lower Goru Formation.

关键词： Sawan Seismic Well-logs Goru formation Cretaceous Petrophysics

Cactus-Shaped Frequency Reconfigurable Antenna for Sub 10 GHz Wireless Applications

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Computer Systems Science & Engineering 2023年第6期45卷 2693-2704页

作者： Muhammad Irfan Wasi ur rehman Khan Sadiq Ullah Naveed Mufti Muhammad Fawad Khan Rizwan Ullah Usman Ali Fazal Muhammad Faisal Althobiani Mohammed Alshareef Shadi Alghaffari Saifur rehman V.R.Shamji Electrical Engineering Department College of EngineeringNajran UniversitySaudi Arabia Department of Telecommunication Engineering University of Engineering and TechnologyMardanKPPakistan Department of Electrical Engineering University of Engineering and TechnologyMardanKPPakistan Faculty of Maritimes Studies King Abdulaziz UniversityJeddahSaudi Arabia Ports&Maritime Transportation Faculty of Maritimes StudiesKing Abdulaziz UniversityJeddahSaudi Arabia Faculty of Maritime Studies King Abdulaziz UniversityJeddahSaudi Arabia

This paper presents,a novel cactus shaped frequency reconfigurable antenna for sub 10 GHz wireless *** diode is utilized as an electrical switch to achieve reconfigurability,enabling operation in four different frequency *** the switch ON state mode,the antenna supports 2177-3431 and 6301-8467 MHz ***,the antenna resonates within 2329-3431 and 4951-6718 MHz while in the OFF state *** efficiency values,ranging from 68%to 84%,and gain values,ranging from 1.6 to 4 dB,in the operating frequency *** proposed antenna satisfy the practical requirements and *** overall planner dimensions of the proposed antenna model is 40×21 mm^(2).Moreover,the measurement results from the prototype support the simulation *** on the frequency ranges supported by the antenna,it can be used for multiple wireless standards and services,including Worldwide interoperability and Microwave Access(WiMAX),Wireless Fidelity(Wi-Fi),Bluetooth,Long Term Evolution(LTE)and satellite *** increases its applicability for use in mobile terminals.

关键词： Antenna frequency reconfigurable PIN diode switch wireless technology

Topology and ferroelectricity in group-V monolayers

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Chinese Physics B 2020年第5期29卷 1-12页

作者： Mutee ur rehman 华陈强陆赟豪 State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China Zhejiang Province Key Laboratory of Quantum Technology and Device Department of PhysicsZhejiang UniversityHangzhou 310027China

The group-V monolayers(MLs)have been studied intensively after the experimental fabrication of two-dimensional(2D)graphene and black *** observation of novel quantum phenomena,such as quantum spin Hall effect and ferroelectricity in group-V elemental layers,has attracted tremendous attention because of the novel physics and promising applications for nanoelectronics in the 2D *** this review,we comprehensively review recent research progress in engineering of topology and ferroelectricity,and several effective methods to control the quantum phase transition are *** then introduce the coupling between topological orders and ferroelectric *** research directions and outlooks are discussed at the end of the *** is expected that the comprehensive overview of topology and ferroelectricity in 2D group-V materials can provide guidelines for researchers in the area and inspire further explorations of interplay between multiple quantum phenomena in low-dimensional systems.

关键词： topology ferroelectricity two-dimensional material group-V element

Incidence of Diabetes in Hepatitis C Patients in Remote Areas of Pakistan:Effect of Co-Morbidity on HCV Treatment Outcomes at Selected Secondary Care Hospitals

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Journal of Clinical and Nursing Research 2022年第4期6卷 61-68页

作者： Muhammad Khalid Khan Tofeeq ur rehman Faculty of Pharmacy Gomal UniversityD.I.Khan29050Pakistan Department of Pharmacy Quaid I Azam UniversityIslamabadPakistan

The management of Hepatitis C(HCV)varies greatly due to *** of Type II Diabetes Mellitus(T2DM)and HCV infection is momentous,however,only limited studies available from remote areas of *** study aimed to assess the incidence of T2DM in Hepatitis C patients,and to measure the treatment outcomes of anti-HCV therapy in co-morbidity of diabetic patients in remote areas of Khyber Pakhtunkhwa Pakistan.A cross-sectional retrospective analysis of HCV patients(n=449)was conducted in the District Hospitals of Bannu and Lakki Marwat,*** diagnosed of HCV infection and having T2DM as comorbidity were included in the *** demographic information and laboratory parameters,such as viral load(VL),hemoglobin(Hb),alanine amino transferase(ALT),and platelet count were collected to measure treatment outcomes.T2DM was found in 33.18%of patients and significant association(p˂0.05)was found with HCV infection as a ***(SOF)and Ribavirin(RBV)therapy reduced the mean(SD)VL(×10^(3))from baseline 357.1±26.23 IU/mL to 14±2.3 IU/mL and 1.3±0.3 IU/mL at 3rd and 6th months of therapy,*** Interferon and Ribavirin(RBV)therapy reduced VL from a baseline 234.57±13.5 IU/mL to 72±7.9 IU/mL and 62±3.7 IU/mL at 3rd and 6th months of therapy,***-Interferon+Ribavirin(RBV)therapy reduced baseline VL from 337±16.27 IU/mL to 18±2.8 and 4±1 at 3^(rd) and 6^(th) month of therapy,***,Hb,ALT,and platelet count showed variations in all the studied groups.T2DM was highly prevalent and significantly associated with HCV in patients of 40 years or above and SOF+RBV combination therapy showed a better response,both in the diabetic and non-diabetic HCV patients compared to earlier the *** further confirm the finding,a study using a larger population of HCV patients with T2DM should be conducted.

关键词： Hepatitis C Type II diabetes mellitus Co-morbidity

铁道车辆蛇行频率变化机理及其对车体蛇行稳定性的影响

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Acta Mechanica Sinica 2023年第8期39卷 148-165页

作者：孙建锋焦卫东蒋永华唐超 Attiq ur rehman 鄂世举 Key Laboratory of Intelligent Operation and Maintenance Technology and Equipment for urban Rail Transit of Zhejiang Province Zhejiang Normal University Jinhua 321004 China School of Engineering Zhejiang Normal University Jinhua 321004 China Xingzhi College Zhejiang Normal University Lanxi 321004 China

蛇行频率是轮轨系统固有的特征参数并随着运行速度的变化而发生连续变化,能够影响车辆系统的模态行为,从而带来了一系列结构共振相关的动力学问题.本文的研究对象从单轮对系统出发扩展至转向架系统和带两级悬挂的整车系统,重点研究了蛇... 详细信息

蛇行频率是轮轨系统固有的特征参数并随着运行速度的变化而发生连续变化,能够影响车辆系统的模态行为,从而带来了一系列结构共振相关的动力学问题.本文的研究对象从单轮对系统出发扩展至转向架系统和带两级悬挂的整车系统,重点研究了蛇行频率的变化机理及其对车体蛇行稳定性的影响机制.文中提出了一种基于最小模态距离的模态跟踪方法,对蛇行频率和其他模态参数进行连续跟踪,研究了速度激励下轮轨系统及悬挂系数参数对蛇行频率的影响机制.利用极限思想揭示了蛇行频率的饱和机理并给出了频率饱和值的解析表达式.结合模态跟踪方法和正则化的振型及动能幅值分布情况,实现了根轨迹曲线的划分与识别.从模态频率、阻尼比和振型角度,分析并总结了在频率耦合速度(蛇行频率与车体刚性模态频率相等时对应的速度)下的模态行为特征.基于速度与等效锥度的联合变参分析,发现频率耦合速度通过影响最小阻尼比对车体蛇行稳定性产生显著影响.除了模态频率外,车体刚性模态的固有阻尼比也会影响频率耦合速度下的系统最小阻尼比.本文的研究工作揭示了蛇行频率的演变机制,丰富了对蛇行运动现象的理解,为现代轨道车辆的稳定性设计提供了理论依据.

关键词：轮轨系统铁道车辆蛇行运动车辆系统等效锥度轨道车辆模态频率阻尼比

Resource Allocation for Two-Way Amplify and Forward OFDM Relay Networks

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China Communications 2017年第8期14卷 76-82页

作者： Zhijun Liu Xiaofeng Tao Waheed ur rehman Wireless Technology Innovation Institute Key Laboratory of Universal Wireless CommunicationsBeijing University of Posts and TelecommunicationsBeijingChina

Physical-layer network coding(PNC) promises substantial theoretical gain to achieve the maximum system throughput in cooperative relay transmission. However, with the increasing global warming, how to reduce power consumption while satisfy system throughput requirement is becoming a vital issue. In this paper, we investigate energy-efficiency resource allocation(RA) based on PNC with amplify-and-forward(AF) protocol in orthogonal frequency division multiple(OFDM) bidirectional transmission. To minimize the overall transmit power consumption with required system throughput requirement, we consider joint subcarriers and power allocation and formulate the objective task into a constrained optimization problem where the best relay node is selected to minimize total transmit power. The closed form optimization power allocation solutions are acquired by analytical derivation. Based on derivation, we propose a novel optimal energy-efficient power allocation(OE-PA). Numerical results are given to evaluate the performance of the derived scheme as compared to other schemes and show that our scheme has signifi cant improvement to energy saving.

关键词：资源分配中继网 ofdm 转发放大系统吞吐量正交频分复用功率分配

Molecular Simulation of Cement-Based Materials and Their Properties

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Engineering 2022年第8期8卷 165-178页

作者： Ashraf A.Bahraq Mohammed A.Al-Osta Omar S.Baghabra Al-Amoudi I.B.Obot Mohammed Maslehuddin Habib-ur-rehman Ahmed Tawfik A.Saleh Department of Civil and Environmental Engineering King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Interdisciplinary Research Center for Construction and Building Materials King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Interdisciplinary Research Center for Advanced Materials King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Department of Chemistry King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

Hydrated cement is one of the complex composite systems due to the presence of multi-scale phases with varying *** silicate hydrate,which is the principal binder phase in the hydrated cement,is responsible for the stiffness,strength,and durability of Portland cement *** understand the mechanical and durability behavior of concrete,it is important to investigate the interactions of hydrated cement phases with other materials at the *** this regard,the molecular simulation of cement-based materials is an effective approach to study the properties and interactions of the cement system at the fundamental ***,many studies have been published regarding atomistic simulations to investigate the cement phases to define/explain the microscopic physical and chemical properties,thereby improving the macroscopic performance of hardened *** research in molecular simulation of cementitious systems involves researchers with multidisciplinary backgrounds,mainly in two areas:(1)cement chemistry,where the hydration reactions govern most of the chemical and physical properties at the atomic scale;and(2)computational materials science and engineering,where the bottom-up approach is *** latter approach is still in its infancy,and as such,a study of the prevailing knowledge is useful,namely through an exhaustive literature *** state-of-theart report provides a comprehensive survey on studies that were conducted in this area and cites the important findings.

关键词： Atomistic simulation Molecular dynamics Cement phases Hydration products Nanoengineering

DFT studies of thermoelectric properties of R-Au intermetallics at 300 K

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Journal of Rare Earths 2018年第2期36卷 197-202页

作者： Sardar Ahmad Rashid Ahmad Muhammad Bilal Najeeb ur rehman Center for Computational Materials Science University of Malakand Department of Chemistry University of Malakand Department of Physics University of Malakand

Thermoelectric and electronic properties of cubic bi-intermetallics R-Au（R = Tb, Ho. Er. Tm and Yb）compounds were explored. Electronic properties i.e. density of states and band structure were computed using first principles calculations which proved the metallic nature of these compounds. Post-DFT（BoltzTraP） calculations were carried out to explore their thermoelectric properties like electrical conductivities. Seebeck coefficient, electronic thermal conductivities and figure of merit. The highest Seebeck coefficient and figure of merit were found for YbAu among these compounds which are 105 μV/K and 0.285 respectively. All the calculations were carried out at 300 K. Large values of figure of merit obtained for these compounds at room temperature indicate that these materials can be used for thermoelectric devices however need experimental verification.

关键词： DFT Seebeck coefficient Figure of merit Thermal conductivity Electrical conductivity R-Au