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复合脉冲控制阶梯型多态量子系统的转移通道

华南师范大学学报（自然科学版） 2020年第4期52卷 31-36页

作者：张钻娴 rehman fazal 陈志文黄巍华南师范大学物理与电信工程学院广州510006

提出了利用复合脉冲在阶梯型多态量子系统中操控量子态演化和粒子数相干转移的方法.首先通过Morris-Shore变换,借助二能级传播算子描述多态量子系统的演化.然后利用增加脉冲序列数且单个脉冲的相位可控的技术,抑制额外的转移通道,实现... 详细信息

提出了利用复合脉冲在阶梯型多态量子系统中操控量子态演化和粒子数相干转移的方法.首先通过Morris-Shore变换,借助二能级传播算子描述多态量子系统的演化.然后利用增加脉冲序列数且单个脉冲的相位可控的技术,抑制额外的转移通道,实现高效率高鲁棒性的量子态操控和粒子数转移.最后通过数值模拟研究了额外通道和转移通道的拉比频率比、脉冲面积的变化、单光子失谐偏离零点等因素对转移效率的影响.结果表明:常被用于二能级量子系统的复合脉冲操控方法也可被应用于多态量子系统.通过增加脉冲序列数,可有效减小相关参数的扰动,保持高效率的粒子数转移.多脉冲序列复合脉冲的技术可以解决偏振不纯、激光频率不纯、控制参数扰动等造成的量子态操控效率降低等问题.研究结果对构造量子门、量子模拟等相关研究具有重要意义.

关键词：量子态操控复合脉冲 Morris-Shore变换多态量子系统

An Efficient Medium Access Control Mechanism for Flying Ad-hoc Networks

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Computer Systems Science & Engineering 2021年第7期38卷 47-63页

作者： Muhammad Asghar Khan fazal Noor Insaf Ullah Sajjad ur rehman Shibli Nisar Mohaira Ahmad Department of Electronic Engineering ISRA UniversityIslamabad44000Pakistan Department of Computer Science and Information Systems Islamic University of MadinahMadinah400411Saudi Arabia Hamdard Institute of Engineering&Technology Islamabad44000Pakistan Department of Electrical Engineering Namal InstituteMianwali42200Pakistan Department of Electrical Engineering National University of Sciences and Technology(NUST)Islamabad44000Pakistan

The Flying Ad-hoc Networks(FANETs)is characterized by the transition from a single large Unmanned Aerial Vehicle(UAV)to multiple small UAVs connected in an ad-hoc *** high mobility is the core feature of such networks,they are prone to route breaks within the *** issue of connectivity loss can be coped with,to some extent,by making use of omnidirectional *** modification,however,curtails Quality-of-Service(QoS)requirements of networks in terms of bandwidth,media access delay,coverage and ***,directional antennas have advantages over omnidirectional antennas such as improved transmission range,spatial reuse and high ***,its introduction raises location-dependent issues to the Medium Access Control(MAC)*** calls for an efficient MAC protocol that can cater to new directional antenna models and,at the same time,can counter the constraints associated with the dynamic ***,in this article,we consider a UAV interconnection mechanism that lets the UAVs execute the communication tasks using the directional MAC *** technique is advantageous as compared to the approach of utilizing the MAC protocol using omnidirectional *** scheme is being implemented as a case study for Industry 4.0 inventory and traceability applications in the *** modeling and simulation purposes,we use the Optimized Network Engineering Tool(OPNET)and aim to seek an evaluation with respect to throughput,media access delay,retransmission attempts and data *** results obtained demonstrate the effectiveness of the proposed scheme.

关键词： FANETs QoS Industry 4.0 IEEE 802.11 MAC OPNET mobility models directional antenna

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

Development of bis-thiobarbiturates as successful urease inhibitors and their molecular modeling studies

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Chinese Chemical Letters 2016年第5期27卷 693-697页

作者： fazal Rahim Muhammad Ali Shifa Ullah Umer Rashid Hayat Ullah Muhammad Taha Muhammad Tariq Javed Wajid rehman Aftab Ahmad Khan Obaid Ur Rahman Abid Muhammad Bilal Department of Chemistry Hazara University Department of Chemistry COMSATS Institute of Information Technology Department of Biochemistry and Biotechnology The Islamia University of Bahawalpur Atta-ur-Rahman Institute for Natural Product Discovery Universiti Teknologi MARA (UiTM)Puncak Alam Campus Faculty of Applied Science UiTM Department of Environmental Science COMSATS Institute of Information Technology

Bis-thiobarbiturate derivatives 1-15 have been synthesized, characterized by 1HNMR and El-MS and screened for urease inhibition. All compounds showed various degree of urease inhibitory activity with iC50 values ranging 7.45 ± 0.12 - 74.24 ± 0.81 μmol/L while the standard thiourea behaved normally （ICso = 21.10 ±0.12）. Compounds I （IC50= 7.45 ± 0.12 ]μmol/L）, 9 （IC50 =18,17 ± 1.03 bmol/L） and 13 （IC50= 8.61 ± 0.45 bmol/L） showed excellent urease inhibitory activity in the series. Molecular modeling studies were performed to understand the binding site with the bimetallic nickel center of the enzyme. Structure-activity relationship has also been established for these compounds. This study identified bis- thiobarbiturate as a novel class of urease inhibitors.

关键词： Thiobarbituric acid Synthesis Urease inhibition Molecular docking studies

Th-Shaped Tunable Multi-Band Antenna for Modern Wireless Applications

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Computers, Materials & Continua 2023年第2期74卷 2517-2530页

作者： Wasi Ur rehman Khan Muhammad Fawad Khan Muhammad Irfan Sadiq Ullah Naveed Mufti Usman Ali Rizwan Ullah fazal Muhammad Saifur Rahman Faisal Althobiani Mohammed Alshareef Mohammad E.Gommosani Department of Telecommunication Engineering University of Engineering and TechnologyMardanPakistan Electrical Engineering Department College of EngineeringNajran UniversityNajranSaudi Arabia Department of Electrical Engineering University of Engineering and TechnologyMardan23200Pakistan Faculty of Maritimes Studies King Abdulaziz UniversityJeddahSaudi Arabia Ports&Maritime Transportation Faculty of Maritimes StudiesKing Abdulaziz UniversityJeddahSaudi Arabia Natural Science Department Faculty of Maritimes StudiesKing Abdulaziz UniversityJeddahSaudi Arabia

A compact,reconfigurable antenna supporting multiple wireless services with a minimum number of switches is found lacking in literature and the same became the focus and outcome of this *** was achieved by designing a Th-Shaped frequency reconfigurable multi-band microstrip planar antenna,based on use of a single switch within the radiating structure of the *** frequency bands(i.e.,2007–2501 MHz,3660–3983MHz and 9341–1046 MHz)can be operated with the switch in the ON switch *** the OFF state of the switch,the antenna operates within the 2577–3280MHz and 9379–1033MHz *** proposed antenna shows an acceptable input impedance match with Voltage Standing Wave Ratio(VSWR)less than *** peak radiation efficiency of the antenna is 82%.A reasonable gain is obtained from 1.22 to 3.31 dB within the operating bands is *** proposed antenna supports UniversalMobile Telecommunication System(UMTS)-1920 to 2170 MHz,Worldwide Interoperability and Microwave Access(WiMAX)/Wireless Broadband/(Long Term Evolution)LTE2500–2500 to 2690 MHz,Fifth Generation(5G)-2500/3500 MHz,Wireless Fidelity(Wi-Fi)/Bluetooth-2400 to 2480 MHz,and Satellite communication applications in X-Band-8000 to 12000 *** overall planar dimension of the proposed antenna is 40×*** antennawas designed,along with the parametric study,using Electromagnetic(EM)simulation *** antenna prototype is fabricated for experimental validation with the simulated *** proposed antenna is low profile,tunable,lightweight,cheap to fabricate and highly efficient and hence is deemed suitable for use in modern wireless communication electronic devices.

关键词： Antenna design reconfigurable antenna satellite communication frequency bands

Ethnobotanical Studies on Dwarf Palm (<i>Nannorhops ritchieana</i>(Griff.) Aitchison) and Date Palm (<i>Phoenix dactylifera</i>L.) in Dera Ismail Khan, KPK, Pakistan

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American Journal of Plant Sciences 2012年第8期3卷 1162-1168页

作者： Sarfaraz Khan Marwat Khalid Usman Ejaz Ahmad Khan Said Ghulam Jalaluddin Baloch Abdul Manan Tauqeer fazal Ur rehman Department of Economics Gomal University Dera Ismail Khan Pakistan Faculty of Agriculture Gomal University Dera Ismail Khan Pakistan Faculty of Pharmacy Gomal University Dera Ismail Khan Pakistan University WENSAM College Gomal University Dera Ismail Khan Pakistan

This paper is based on research work conducted during 2008-2010 in Dera Ismail Khan (D. I. Khan) District, Pakistan, to investigate Socio-Economic Impacts of Dwarf Palm (Nannorhops ritchieana) and Date Palm (Phoenix dactylifera) on the local inhabitants. A questionnaire for data collection of Dwarf Palm was designed and local people were interviewed. The main Dwarf Palm (Mazri) areas are lying between the Koh-i-Surkh and Marwat hill and yielding about 1000 tons of mazri leaves annually. Date Palm plantations are concentrated in Paniala, Paharpur, Chawdwan and Dhakki. The prominent varieties grown in the area are Dhakki, Shakri, Gulistan, Zaidi, Hillawi, Basra, Azadi and khudarawi. Dhakki Dates are well-known among all other varieties. Total area under dates cultivation in the district is 100,000 hectares, with total production of 11,000 tons dates. An average yield of Dhakki-Dates y-1 ranges from 6500 to 7000 tons i.e., 75% of the total production of dates in the area and dried dates production ranges from 800 - 1000 tons·year-1. A significant population is involved in processing of mazri and date palm leaves to prepare different products. Dates have a tremendous potential for economic uplift of the people. But growers face limitations and challenges regarding lack of information about customers and markets, harvesting, processing, and packaging techniques and infrastructure for producing good quality fresh dates. Fruit dropping in date palm particularly in Dhakki variety has become a serious concern. More than 70% date fruits drop before maturity. If production and processing constraints are properly handled, this may have significant socio-economic impact on local inhabitants.

关键词： Mazri Palm Date Palm Arecaceae Socio-Economic Impact

Hot DRI for Productivity Enhancement ＆ Energy Conservation

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Hot DRI for Productivity Enhancement ＆ Energy Conservation