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Control of Wave Propagation and Effect of Kerr Nonlinearity on Group Index

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Communications in Theoretical Physics 2013年第7期60卷 87-92页

作者： Hazrat Ali Ziauddin iftikhar ahmed Department of Physics University of Malakand Department of Physics COMSATS Institute of Information Technology

We use four-level atomic system and control the wave propagation via forbidden decay rate. The Raman gain process becomes dominant on electromagnetically induced transparency (EIT) medium by increasing the forbidden decay rate via increasing the number of atoms [G.S. Agarwal and T.N. Dey, Phys. Rev. A 74 (2005) 043805 and K. Harada, T. Kanbashi, and M. Mitsunaga, Phys. Rev. A 73 (2006) 013803]. The behavior of wave propagation is dramatically changed from normal (subluminal) to anomalous (superluminal) dispersion by increasing the forbidden decay rate. The system can also give a control over the group velocity of the light propagating through the medium via Kerr field.

关键词： normal and anomalous dispersion Kerr field group index

青藏高原及其周边成冰纪-埃迪卡拉纪综合地层、生物群与古地理演化

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中国科学：地球科学 2024年第4期54卷 936-967页

作者：孙郎 malik Muhammad Saud Sajid KHAN 杨传孙智新潘兵 Shehryar ahmed 苗兰云孙玮辰胡春林孙晓娟罗翠陈波殷宗军赵方臣李国祥朱茂炎中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室南京210008 中国科学院大学地球与行星科学学院北京100049

青藏高原及其周边的块体,包括印度板块、拉萨地块、羌塘地块、塔里木板块、欧龙布鲁克地块、中祁连地块、阿拉善地块、华北板块、扬子板块、中伊朗地块和阿曼等,以及各块体之间造山带的复杂演化历史是地球科学研究的前沿和热点.成冰系... 详细信息

青藏高原及其周边的块体,包括印度板块、拉萨地块、羌塘地块、塔里木板块、欧龙布鲁克地块、中祁连地块、阿拉善地块、华北板块、扬子板块、中伊朗地块和阿曼等,以及各块体之间造山带的复杂演化历史是地球科学研究的前沿和热点.成冰系和埃迪卡拉系广泛分布于该地区的各个构造单元,其中阿曼、印度板块、扬子板块以及塔里木板块发育有相对完整的成冰系和埃迪卡拉系;而在中伊朗地块、南羌塘地块、中祁连地块、阿拉善地块及华北板块,目前已知仅有埃迪卡拉系发育.基于前人对青藏高原及其周边地区成冰系和埃迪卡拉系的研究,结合第二次青藏高原综合科学考察研究项目开展以来获得的新资料和研究进展,本文建立了该地区成冰系和埃迪卡拉系代表性地层序列对比表.在此基础上,本文梳理了该地区这一时期生物群和重大地质事件的研究现状和存在的问题.结果表明,该地区各板块埃迪卡拉纪化石的保存和组合面貌各具特色,但普遍发现有典型埃迪卡拉纪末期化石分子Cloudina和Shaanxilithes;除成冰纪两次全球性冰期事件外,在青藏高原北缘各块体(华北板块、阿拉善地块、北祁连构造带、中祁连地块、欧龙布鲁克地块、塔里木板块)以及伊朗中南部普遍记录了一次埃迪卡拉纪晚期的冰川事件,但该事件的时限、分布范围和成因有待进一步揭示;同时,埃迪卡拉纪中期DOUNCE/Shruam碳同位素负异常事件在青藏高原周边地区也具有广泛记录.综合现有研究资料发现,在成冰纪-埃迪卡拉纪期间,青藏高原及其周边地区大多数块体从罗迪尼亚超大陆裂解出来后,可能通过泛非运动构成东冈瓦纳大陆的一部分,而部分板块(如华北板块)位于冈瓦纳大陆和劳伦大陆之间.总体而言,该地区的主要块体在成冰纪-埃迪卡拉纪期间具体的古地理演化模型存在较多争议,亟需开展进一步的研究工作.

关键词：青藏高原成冰系埃迪卡拉系地层古地理生物群冈瓦纳大陆

Vehicle Detection in Challenging Scenes Using CenterNet Based Approach

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Computers, Materials & Continua 2023年第2期74卷 3647-3661页

作者： Ayesha Muhammad Javed Iqbal iftikhar Ahmad Madini OAlassafi ahmed SAlfakeeh ahmed Alhomoud Department of Computer Science University of Engineering and Technology Taxila47050Pakistan Faculty of Computing and Information Technology King Abdulaziz University Jeddah21589Saudi Arabia Faculty of Computing and Information Technology Northern Border UniversityRafhaSaudi Arabia

Contemporarily numerous analysts labored in the field of Vehicle detection which improves Intelligent Transport System(ITS)and reduces road *** major obstacles in automatic detection of tiny vehicles are due to occlusion,environmental conditions,illumination,view angles and variation in size of *** research centers on tiny and partially occluded vehicle detection and identification in challenging scene specifically in crowed *** this paper we present comprehensive methodology of tiny vehicle detection using Deep Neural Networks(DNN)namely *** DNN disregards objects that are small in size 5 pixels and more false positives likely to happen in crowded *** there are two categories of deep learning models single-step and two-step.A single forward pass model is the one in which detection is performed directly to possible location over dense sampling,wherein two-step models incorporated by Region proposals followed by object *** in this research scrutinize one-step State of the art(SOTA)model CenteNet as proposed recently with three different feature extractor ResNet-50,HourGlass-104 and ResNet-101 one by *** train our model on challenging KITTI dataset which outperforms in comparison with SOTA single-step technique MSSD300∗which depicts performance improvement by 20.2%mAPandSMOKEby with 13.2%mAP *** of CenterNet can be justified through the huge improved *** performance of our model is evaluated on KITTI(Karlsruhe Institute of Technology and Toyota Technological Institute)benchmark dataset with different backbones such as ResNet-50 gives 62.3%mAP ResNet-10182.5%mAP,last but not the least HourGlass-104 outperforms with 98.2%mAP CenterNet-HourGlass-104 achieved high mAP among above mentioned feature *** also compare our model with other SOTA techniques.

关键词： CenteNet SOTA object detection deep learning MSSD SMOKE DNN KITTI

Chemical and Thermal Characterization of Cement Mortar Containing Ground Palm Oil Fuel Ash as a Partial Cement Replacement

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Journal of Wuhan University of Technology(Materials Science) 2023年第3期38卷 575-581页

作者： SUMRA Yousuf PAYAM Shafigh iftikhar ahmed Channa M Rizwan TANVEER ahmed Khan BELAL Alsubari MUSTABSHIRHA Gul l.Department of Building and Architectural Engineering Faculty of Engineering&TechnologyBahauddin Zakariya University60000 MultanPakistan Centre for Building Construction&Tropical Architecture(BuCTA)Faculty of Built EnvironmentUniversity of Malaya50603 Kuala LumpurMalaysia Department of Metallurgical Engineering NED University of Engineering and Technology74200 KarachiPakistan Department of Civil Engineering Faculty of EngineeringMiami College of Henan UniversityKaifeng475001China Department of Mechanical Engineering University of Malaya50603 Kuala LumpurMalaysia Department of Mechanical Engineering Faculty of Engineering&TechnologyBahauddin Zakariya University60000 MultanPakistan

This study investigates the influence of using ground palm oil fuel ash(G-POFA) from 10%-30% as cement replacement(by weight) on the cement mortar's pH under various curing conditions. These findings were supplemented by thermal gravimetric analysis(TGA). Moreover, the resistance of G-POFA blended cement mortars to water absorption and sorptivity was determined. Further, the k-value test was carried out to explain the pozzolanic and filler behavior of G-POFA and to support the results obtained from TGA. It was found that there was no significant impact of several curing conditions on the pH of mortars. The mortar with 10% G-POFA in replacement of cement(G-POFA-10) exhibited the best resistance against water absorption and sorptivity.

关键词： curing condition Ca(OH)_(2)content k-value pH palm oil fuel ash

Investigating the Use of Email Application in Illiterate and Semi-Illiterate Population

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Computers, Materials & Continua 2020年第3期62卷 1473-1486页

作者： Sadeeq Jan Imran Maqsood Salman ahmed Zahid Wadud iftikhar Ahmad National Center for Cyber Security-UETP Department of CS&ITUniversity of Engineering&TechnologyPeshawarPakistan Department of Computer Software Engineering University of Engineering&TechnologyMardanPakistan Department of Computer Systems Engineering University of Engineering&TechnologyPeshawarPakistan 不详

The use of electronic communication has been significantly increased over the last few *** is one of the most well-known means of electronic *** email applications are widely used by a large population;however,illiterate and semi-illiterate people face challenges in using them.A major population of Pakistan is illiterate that has little or no practice of computer *** this paper,we investigate the challenges of using email applications by illiterate and semi-illiterate *** addition,we also propose a solution by developing an application tailored to the needs of illiterate/semi-illiterate *** shows that illiterate people are good at learning the designs that convey information with pictures instead of text-only,and focus more on one object/action at a *** proposed solution is based on designing user interfaces that consist of icons and vocal/audio instructions instead of ***,we use background voice/audio which is more helpful than flooding a picture with a lot of *** tested our application using a large number of users with various skill levels(from no computer knowledge to experts).Our results of the usability tests indicate that the application can be used by illiterate people without any training or third-party’s help.

关键词： Illiterate semi-illiterate email usability user interfaces

Challenges of modern day transition care in inflammatory bowel disease: From inflammatory bowel disease to biosimilars

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World Journal of Gastroenterology 2017年第25期23卷 4473-4479页

作者： Ali Hakizimana iftikhar ahmed Rachel Russell Mark Wright Nadeem A Afzal Department of Paediatrics University Hospital Southampton Department of Gastroenterology University Hospital Southampton Department of Hepatology University Hospital Southampton

In this article we discuss the challenges of delivering a high quality Transition care. A good understanding of the adolescent needs with good communication between Transition care physicians and the patient is essential for good continuity of care. Despite availability of several guidelines, one model doesn't fit all and any transition service development should be determined by the local need and available healthcare facilities.

关键词： Transition Adolescent Inflammatory bowel disease Biosimilar

Field evaluation of some bait additives against Indian crested porcupine(Hystrix indica)(Rodentia:Hystricidae)

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Integrative Zoology 2013年第3期8卷 285-292页

作者： Muhammad MUSHTAQ iftikhar HUSSAIN Afsar MIAN Shahid MUNIR Irfan ahmed Abdul Aziz KHAN Department of Zoology PMAS Arid Agriculture UniversityRawalpindiPakistan Wildlife Management PMAS Arid Agriculture UniversityRawalpindiPakistan National Agricultural Research Centre IslamabadPakistan

This research study evaluated the effect of different additives on the bait consumption by Indian crested porcupine,a serious forest and agricultural pest,under field *** additives(saccharin,common salt,bone meal,fish meal,peanut butter,egg yolk,egg shell powder,yeast powder,mineral oil and coconut oil)at 2 and 5%each were tested for their relative preference,using groundnut-maize(1:1)as basic *** the additives were tested under a no-choice test *** control tests,no additive was mixed with the basic *** at 5%concentration significantly enhanced the consumption of bait over the basic bait,while 2%saccharin supplemented bait resulted in a non-significant bait *** other additives did not enhance the consumption of the bait material;rather,these worked as ***,the repellency was lowest with the common salt,followed by egg yolk,egg shell powder,bone meal,peanut butter,mineral oil,fish meal and yeast powder,while coconut remained the most repellent *** present study suggested that groundnut-maize(1:1)supplemented with 5%saccharin was the preferred bait combination,and can be used with different rodenticides for the management of Indian crested porcupine.

关键词： additives baits evaluation Hystrix indica Indian crested porcupine

Visual object tracking- classical and contemporary approaches

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Frontiers of Computer Science 2016年第1期10卷 167-188页

作者： Ahmad ALI Abdul JALIL Jianwei NIU Xiaoke ZHAO Saima RATHORE Javed ahmed Muhammad AKSAM iftikhar Department of Computer and Information Sciences Pakistan Institute of Engineering & Applied Sciences Islamabad 44000 Pakistan State Key Laboratory of Virtual Reality Technology and Systems School of Computer Science and Engineering Beihang University Beijing 100191 China Department of Electrical (Telecom) Engineering NUST Military College of Signals Islamabad 44000 Pakistan COMSATS Institute of Information Technology Lahore 54000 Pakistan

Visual object tracking （VOT） is an important sub- field of computer vision. It has widespread application do- mains, and has been considered as an important part of surveillance and security system. VOA facilitates finding the position of target in image coordinates of video frames. While doing this, VOA also faces many challenges such as noise, clutter, occlusion, rapid change in object appearances, highly maneuvered （complex） object motion, illumination changes. In recent years, VOT has made significant progress due to availability of low-cost high-quality video cameras as well as fast computational resources, and many modern techniques have been proposed to handle the challenges faced by VOT. This article introduces the readers to 1） VOT and its applica- tions in other domains, 2） different issues which arise in it, 3） various classical as well as contemporary approaches for object tracking, 4） evaluation methodologies for VOT, and 5） online resources, i.e., annotated datasets and source code available for various tracking techniques.

关键词： visual object tracking computer vision imageprocessing point tracking kernel tracking silhouette track-ing

Accurate Location Estimation of Smart Dusts Using Machine Learning

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Computers, Materials & Continua 2022年第6期71卷 6165-6181页

作者： Shariq Bashir Owais ahmed malik Daphne Teck Ching Lai Institute of Applied Data Analytics(IADA) Universiti Brunei Darussalam(UBD)GadongBE1410Brunei Darussalam School of Digital Sciences(SDS) Universiti Brunei Darussalam(UBD)GadongBE1410Brunei Darussalam

Traditional wireless sensor networks(WSNs)are not suitable for rough terrains that are difficult or impossible to access by *** dust is a technology that works with the combination of many tiny sensors which is highly useful for obtaining remote sensing information from rough *** tiny sensors are sprinkled in large numbers on rough terrains using airborne distribution through drones or aircraftwithout manually setting their *** it is clear that a number of remote sensing applications can benefit from this technology,but the small size of smart dust fundamentally restricts the integration of advanced hardware on tiny *** raises many challenges including how to estimate the location of events sensed by the smart *** solutions on estimating the location of events sensed by the smart dusts are not suitable for monitoring rough terrains as these solutions depend on relay sensors and laser patterns which have their own limitations in terms of power constraint and uneven *** study proposes a novel machine learning based localization algorithm for estimating the location of *** approach utilizes timestamps(time of arrival)of sensed events received at base stations by assembling them into a multidimensional vector and input to a machine learning classifier for estimating the *** to the unavailability of real smart dusts,we built a simulator for analysing the accuracy of the proposed approach formonitoring forest *** experiments on the simulator show reasonable accuracy of the approach.

关键词： Smart dust sensor localization remote sensing machine learning algorithms Internet of Things sensor applications