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| 1 | Modeling and Backstepping-based Nonlinear Control Strategy for a 6 DOF Quadrotor Helicopter显示文摘In this article,a nonlinear model of an underactuated six degrees of freedom (6 DOF) quadrotor helicopter is derived on the basis of the Newton-Euler formalism. The derivation comprises determining equations of the motion of the quadrotor in three dimensions and approximating the actuation forces through the modeling of aerodynamic coefficients and electric motor dynamics. The derived model composed of translational and rotational subsystems is dynamically unstable,so a sequential nonlinear control strategy is used. The con-trol strategy includes feedback linearization coupled with a PD controller for the translational subsystem and a backstepping-based PID nonlinear controller for the rotational subsystem of the quadrotor. The performances of the nonlinear control method are evaluated by nonlinear simulation and the results demonstrate the effectiveness of the proposed control strategy for the quadrotor helicopter in quasi-stationary flights. | Ashfaq Ahmad Mian | 2008 | Chinese Journal of Aeronautics2008，21，3： | 54 |
| 2 | Claudin18和annexinA8:应用差异基因表达分析鉴定的新的胰腺癌标记物显示文摘 | Karanjawala Z Illei P B Ashfaq R 黄文斌(摘译) | 2008 | 临床与实验病理学杂志2008，24，3： | 17 |
| 3 | Prevalence of gastric varices and results of sclerotherapy with N-butyl 2 cyanoacrylate for controlling acute gastric variceal bleeding显示文摘AIM: To study the prevalence, predictors and control of bleeding following N-butyl 2 cyanoacrylate (NBC) sclerotherapy of gastric varix (GV). METHODS: We analyzed case records of 1436 patients with portal hypertension, who underwent endoscopy during the past five years for variceal screening or upper gastrointestinal (GI) bleeding. Fifty patients with bleeding GV underwent sclerotherapy with a mean of 2 mL NBC for control of bleeding. Outcome parameters were primary hemostasis (bleeding control within the first 48 h), recurrent bleeding (after 48 h of esophago- gastro-duodenoscopy) and in-hospital mortality were analyzed. RESULTS: The prevalence of GV in patients with portal hypertension was 15% (220/1436) and the incidence of bleeding was 22.7% (50/220). Out of the 50 bleeding GV patients, isolated gastric varices (IGV-I) were seen in 22 (44%), gastro-oesophageal varices (GOV) on lesser curvature (GOV-Ⅰ) in 16 (32%), and GOV on greater curvature (GOV-Ⅱ) in 15 (30%). IGV-Ⅰ was seen in 44% (22/50) patients who had bleeding as compared to 23% (39/170) who did not have bleeding (P < 0.003). Primary hemostasis was achieved with NBC in all patients. Re-bleeding occurred in 7 (14%) patients after 48 h of initial sclerotherapy. Secondary hemostasis was achieved with repeat NBC sclerotherapy in 4/7 (57%). Three patients died after repeat sclerotherapy, one during transjugular intrahepatic portosystemic stem shunt (TIPSS), one during surgery and one due to uncontrolled bleeding. Treatment failure-related mortality rate was 6% (3/50). CONCLUSION: GV can be seen in 15% of patients withportal hypertension and the incidence of bleeding is 22.7%. NBC is highly effective in controlling GV bleeding. In hospital mortality of patients with bleeding GV is 6%. | Khalid Mumtaz Shahid Majid Hasnain A Shah Kashif Hameed Ashfaq Ahmed Saeed Hamid Wasim Jafri | 2007 | World Journal of Gastroenterology2007，13，8： | 12 |
| 4 | 颈部动脉夹层分离及其与颈椎推拿疗法的联系:美国心脏协会/美国卒中协会对医疗专业人员的声明显示文摘目的:颈部动脉夹层分离(cervicalarterydissection,CD)是中青年人卒中的最常见病因。本指南旨在对CD诊治的现有证据水平以及其与颈椎推拿疗法(cervical manipulative therapy, CMT)的统计学联系进行回顾。某些类型的CMT是由医疗专业人员对颈椎施加猛烈或轻柔的推力。方法写作组成员由美国心脏协会卒中委员会的科学声明监督委员会以及美国心脏协会的手稿监督委员会任命。各成员负责与其专业领域相关的主题,回顾适当的文献并参考公开发表的临床和流行病学研究、发病率和死亡率报告、临床与公共卫生指南、权威声明、个人文件以及专家意见,对现有证据进行总结并指出目前的知识空白。结果CD患者可表现为单侧头痛、后颈部痛或主要由动脉-动脉栓塞导致的脑或视网膜缺血(短暂性缺血或卒中)、CD脑神经麻痹、眼交感神经麻痹或搏动性耳鸣。CD的诊断依赖于完整的病史、体格检查和针对性的辅助检查。尽管轻微创伤的作用存在争议,但机械压力可造成椎动脉和颈内动脉内膜损伤,进而导致CD。CD患者的残疾程度存在差异,一些患者预后良好,但有些患者则会出现严重神经系统后遗症。目前尚无循证指南可用来指导CD的最佳处理策略。抗血小板和抗凝治疗均被用于局部血栓和继发性栓塞的预防。病例对照研究和其他文献提示CD[尤其是椎动脉夹层分离(vertebral artery dissection, VAD)]与CMT之间存在流行病学联系,但尚不清楚这是由于对先前存在的CD认识不足还是CMT导致的创伤。超声、CT血管造影以及磁共振血管造影都有助于CD的诊断。神经影像学随访首选无创性检查措施,但我们认为任何单一的检查方法都不能作为金标准。结论 CD是中青年患者发生缺血性卒中的重要病因。CD最好发于颈椎上段,可累及颈内动脉或椎动脉。尽管目前的生物力学证据不足以证实CMT 可导致CD,但临床报道提示机械压力在相当一部分CD中起着一定的作用,而且大多数基于人群的对照研究在年轻患者中显示CMT与VAD卒中之间存在联系。尽管对于曾经接受过CMT的患者,CMT相关性CD的发生率尚不完全清楚并且很可能较低,但当有临床症状时,医生应考虑到CD的可能性,并且在进行颈椎推拿前告知患者CD与CMT之间的统计学联系。 | José Biller Ralph L. Sacco Felipe C. Albuquerque Bart M. Demaerschalk Pierre Fayad Preston H. Long Lori D. Noorollah Peter D. Panagos Wouter I. Schievink Neil E. Schw artz Ashfaq Shuaib David E. Thaler David L. Tirschw ell 牛牧 陈进 宋艳 吴丹 王玉琴 柯开富 | 2015 | 国际脑血管病杂志2015，23，5： | 8 |
| 5 | Biomathematical study of time-dependent flow of a Carreau nanofluid through inclined catheterized arteries with overlapping stenosis显示文摘This work is concerned with the analysis of blood flow through inclined catheterized arteries having a balloon(angioplasty) with time-variant overlapping stenosis. The nature of blood in small arteries is analyzed mathematically by considering it as a Carreau nanofluid. The highly nonlinear momentum equations of nanofluid model are simplified by considering the mild stenosis case. The formulated problem is solved by a homotopy perturbation expansion in terms of a variant of the Weissenberg number to obtain explicit forms for the axial velocity, the stream function, the pressure gradient, the resistance impedance and the wall shear stress distribution. These solutions depend on the Brownian motion number, thermophoresis number, local temperature Grashof number G_r and local nanoparticle Grash of number B_r. The results were also studied for various values of the physical parameters, such as the Weissenberg number W_i, the power law index n, the taper angle φ, the maximum height of stenosis δ~*, the angle of inclination α, the maximum height of balloon σ~*, the axial displacement of the balloon z_d~*,the flow rate F and the Froud number Fr. The obtained results show that the transmission of axial velocity curves through a Newtonian fluid(Wi=0, n=1, Gr=0, Br=0, Nt=0, Nb≠0) is substantially lower than that through a Carreau nanofluid near the wall of balloon while the inverse occurs in the region between the balloon and stenosis. The streamlines have a clearly distinguished shifting toward the stenotic region and this shifting appears near the wall of the balloon, while it has almost disappeared near the stenotic wall and the trapping bolus in the case of horizontal arteries and Newtonian fluid(Wi=0, n=1, Gr=0, Br=0, Nt=0, Nb≠0) does not appear but for the case of Carreau nanofluid bolus appears. | Ashfaq Ahmed Sohail Nadeem | 2017 | Journal of Central South University2017，24，11： | 6 |
| 6 | Evaluation of potential RNA-interference-target genes to control cotton mealybug, Phenacoccus solenopsis (Hemiptera: Pseudococcuidae)显示文摘 | Arif M. Khan Muhammad Ashfaq Azhar A. Khan Muhammad T. Naseem Shahid Mansoor | 2018 | Insect Science2018，25，5： | 5 |
| 7 | RNAi:antiviral therapy against dengue virus显示文摘Dengue virus infection has become a global threat affecting around 100 countries in the world.Currently,there is no licensed antiviral agent available against dengue.Thus,there is a strong need to develop therapeutic strategies that can tackle this life threatening disease.RNA interference is an important and effective gene silencing process which degrades targeted RNA by a sequence specific process.Several studies have been conducted during the last decade to evaluate the efficiency of siRNA in inhibiting dengue virus replication.This review summarizes siRNAs as a therapeutic approach against dengue virus serotypes and concludes that siRNAs against virus and host genes can be next generation treatment of dengue virus infection. | Sobia Idrees Usman A Ashfaq | 2013 | Asian Pacific Journal of Tropical Biomedicine2013，3，3： | 5 |
| 8 | Dual behavior of HCV Core gene in regulation of apoptosis is important in progression of HCC显示文摘 | Shah Jahan Usman A. Ashfaq Saba Khaliq Baila Samreen Nadeem Afzal | 2012 | Infection Genetics and Evolution2012，，2： | 4 |
| 9 | 无人直升机鲁棒跟踪解耦飞行控制研究显示文摘综合考虑直升机不确定性、阵风扰动影响及飞行品质规范对直升机操纵品质的要求,提出了一种基于跟踪解耦的无人直升机鲁棒控制方法。以直升机的稳定性导数及控制导数的有界区间摄动来描述系统的不确定性,通过将不确定性系统的跟踪控制问题转化为增广系统的鲁棒状态反馈镇定问题,以线性矩阵不等式(LM I)形式给出了无人直升机鲁棒跟踪解耦控制器存在的充分条件。基于鲁棒跟踪解耦控制方法设计了直升机平移速度指令(TRC)飞行控制器,并结合直升机操纵品质规范ADS-33E对系统性能进行了评估,分析结果表明了鲁棒跟踪解耦控制方法的有效性。 | 王宏强 王道波 Ashfaq Ahmad Mian 段海滨 | 2009 | 机械科学与技术2009，28，4： | 3 |
| 10 | Dynamic modeling and nonlinear control strategy for an underactuated quad rotor rotorcraft显示文摘In this paper, a nonlinear dynamic MIMO model of a 6-DOF underactuated quad rotor rotorcraft is derived based on Newton-Euler formalism. The derivation comprises determining equations of motion of the quad rotor in three dimensions and seeking to approximate the actuation forces through modeling of the aerodynamic coefficients and electric motor dynamics. The derived model is dynamically unstable, so a sequential nonlinear control strategy is implemented for the quad rotor. The control strategy includes exact feedback linearization technique, using the geometric methods of nonlinear control. The performance of the nonlinear control algorithm is evaluated using simulation and the results show the effectiveness of the proposed control strategy for the quad rotor rotorcraft near quasi-stationary flight. | Ashfaq Ahmad MIAN | 2008 | Journal of Zhejiang University-Science A(Applied Physics & Engineering)2008，9，4： | 3 |
| 11 | UV Assisted Preliminary DNA Binding Studies and Single-crystal X-ray Structure of 4-{(4-Nitrophenyl-sulfonamido)methyl}cyclohexanecarboxylic Acid显示文摘A new sulfonamide, 4-{(4-nitrophenylsulfonamido)methyl}cyclohexanecarboxylic acid(C14H18N2O6S), has been synthesized by the reaction of tranexamic acid and 4-nitrobenzenesulfonyl chloride in basic medium at room temperature. The molecular structure was determined by FT-IR, NMR, elemental analysis and single-crystal X-ray technique. X-ray diffraction shows that the compound crystallizes in the monoclinic system, space group P21/c with a = 13.5980(7), b = 4.9877(2), c = 23.3878(13) ?, β = 93.254(3)o, Z = 4, V = 1583.67(14) ?3, μ = 0.237 mm-1, F(000) = 720, R = 0.0471 and w R = 0.1182. The molecules are related by inversion and paired into dimers via C–H···O interactions. The dimmers are interlinked due to strong N–H···O bonds, where O-atoms are of sulfonyl groups. The molecules are stabilized in the form of infinite two-dimensional network with base vectors [0 1 0] and [0 0 –1] in the plane(1 0 2). The existence of good intermolecular interactions suggests the biological importance of the synthesized molecule. The compound was screened for its interaction with FS-DNA using UV-visible spectroscopy. UV-visible spectroscopic results depict that the compound interacts with DNA by mixed binding mode intercalation along with hydrogen bonding. Negative values of ΔG(–23.34, –17.79 k J·mol-1) indicate spontaneity of the compound-DNA adduct formation. | MUHAMMAD Danish RABIA Ayub Butt MUHAMMAD Nawaz Tahir MUHAMMAD Ashfaq SYEDA Tahira Hafeez | 2017 | Chinese Journal of Structural Chemistry2017，36，5： | 3 |
| 12 | Collateral blood vessels in acute ischaemic stroke: a potential therapeutic target显示文摘 | Ashfaq Shuaib Ken Butcher Askar A Mohammad Maher Saqqur David S Liebeskind | 2011 | Lancet Neurology2011，，10： | 3 |
| 13 | Bed planting of wheat(Triticum aestivum L.)improves nitrogen use efficiency and grain yield compared to flat planting显示文摘Conventional flat planting is commonly used for growing wheat in Pakistan and the crop is irrigated by flood irrigation, but it leads to ineffective use of applied nitrogen owing to poor aeration and leaching and volatilization losses. The practice also results in greater crop lodging, lower water use efficiency, and crusting of the soil surface. In contrast, bed planting of wheat not only saves water but improves fertilizer use efficiency and grain yield. Three years of pooled data from the present study showed that wheat planting on beds and nitrogen application at 120 kg ha-1produced 15.06% higher grain yield than flat planting at the same nitrogen rate. Similarly, 25.04%, 15.02%, 14.59%, and 29.83% higher nitrogen uptake, nitrogen use, and agronomic and recovery efficiencies, respectively, were recorded for bed compared to flat planting. Wheat planting on beds with a nitrogen application of80 kg ha-1gave a yield similar to that of flat planting with 120 kg ha-1nitrogen. However,the economic return was 29% higher in bed planting as compared to flat planting, when nitrogen was applied at 120 kg ha-1. | Abdul Majeed Atif Muhmood Abid Niaz Shahid Javid Zahid Ashfaq Ahmad Syed Shahid Hussain Shah Asrar Hussain Shah | 2015 | The Crop Journal2015，3，2： | 3 |
| 14 | Entropy squeezing of an atom with a k-photon in the Jaynes-Cummings model显示文摘The entropy squeezing of an atom with a k-photon in the Jaynes-Cummings model is investigated. For comparison, we also study the corresponding variance squeezing and atomic inversion. Analytical results show that entropy squeezing is preferable to variance squeezing for zero atomic inversion. Moreover, for initial conditions of the system the relation between squeezing and photon transition number is also discussed. This provides a theoretical approach to finding out the optimal entropy squeezing. | 康冬鹏 廖庆洪 Ahamd Muhammad Ashfaq 王月媛 刘树田 | 2010 | Chinese Physics B2010，19，1： | 3 |
| 15 | Structural and optical properties of thermally reduced graphene oxide for energy devices显示文摘Natural intercalation of the graphite oxide, obtained as a product of Hummer's method, via ultra-sonication of water dispersed graphite oxide has been carried out to obtain graphene oxide(GO) and thermally reduced graphene oxide(RGO).Here we report the effect of metallic nitrate on the oxidation properties of graphite and then formation of metallic oxide(MO) composites with GO and RGO for the first time. We observed a change in the efficiency of the oxidation process as we replaced the conventionally used sodium nitrate with that of nickel nitrate Ni(NO_3)_2, cadmium nitrate Cd(NO_3)_2,and zinc nitrate Zn(NO_3)_2. The structural properties were investigated by x-ray diffraction and observed the successful formation of composite of MO–GO and MO–RGO(M = Zn, Cd, Ni). We sought to study the effect on the oxidation process through optical characterization via UV-Vis spectroscopy and Fourier Transform Infrared(FTIR) spectroscopy.Moreover, Thermo Gravimetric Analysis(TGA) was carried out to confirm > 90% weight loss in each process thus proving the reliability of the oxidation cycles. We have found that the nature of the oxidation process of graphite powder and its optical and electrochemical characteristics can be tuned by replacing the sodium nitrate(NaNO_3) by other metallic nitrates as Cd(NO_3)_2, Ni(NO_3)_2, and Zn(NO_3)_2. On the basis of obtained results, the synthesized GO and RGO may be expected as a promising material in antibacterial activity and in electrodes fabrication for energy devices such as solar cell, fuel cell,and super capacitors. | Ayesha Jamil Faiza Mustafa Samia Aslam Usman Arshad Muhammad Ashfaq Ahmad | 2017 | Chinese Physics B2017，26，8： | 3 |
| 16 | High throughput sequencing reveals Drosophila suzukiiresponses to insecticides显示文摘Global climate change and acquired resistance to insecticides are threats to world food security.Drosophila suzukii,a devastating invasive pest in many parts of the world,causes substantial economic losses to fruit production industries,forcing farmers to apply broad-spectrum insecticides frequently,This could lead to the development of insecticide resistance.We determined the Lethal Concentration 50 (median lethal concen- tration,LC50)values of zeta-cypermethrin,spinosad,and malathion insecticides against D.suzukii colonies established from Clarke and Pierce county Georgia,United States. The LC50 values were 3 fold higher in the Pierce county population for all insecticide treatments.We then used RNA sequencing to analyze the responses of Pierce and Clarke population flies surviving a LC50 treatment of the 3 insecticides.We identified a high num- ber of differentially expressed genes that are likely involved in detoxification and reduced cuticular penetration,especially in the Pierce population,with extensive overlap in differ- entially expressed genes between the 3 insecticide treatments.Finally,we predicted fewer nonsynonymous single nucleotide variants having deleterious effects on protein function among detoxification,insecticide target,and cuticular protein encoding genes in Pierce flies.Thus a combination of increased gene expression and fewer deleterious single nu- cleotide variants highlights molecular mechanisms underlying the higher LC50 values for Pierce population flies. | Ruchir Mishra Joanna C.Chiu Gang Hua Nilesh R.Tawari Michael J.Adang Ashfaq A.Sial | 2018 | Insect Science2018，25，6： | 2 |
| 17 | Loss of p27 nuclear expression in a prognostically favorable subset of well-differentiated pancreatic neoplasms 显示文摘 | Rahman A Maitra A Ashfaq R | 2003 | Am J Clin pathol2003，120，5： | 2 |
| 18 | HBV Induced HCC: Major Risk Factors from Genetic to Molecular Level显示文摘 | Ambreen Ayub Usman Ali Ashfaq Asma Haque Haruki Komatsu | 2013 | BioMed Research International2013，，： | 2 |
| 19 | 桔小实蝇中国与马来西亚种群间杂交:融合性、生物学及检疫挑战(英文)显示文摘桔小实蝇是重要的检疫性害虫,可对水果产业造成巨大经济损失。本研究首先采用微卫星标记比较桔小实蝇不同地理种群间的遗传差异性,然后通过室内种间杂交试验,研究了两个相异地理种群(此前称谓的来自中国的桔小实蝇和来自马来西亚的木瓜实蝇)之间杂交后代在繁殖力、孵化率、发育历期、产卵管长度以及抗逆性等方面的适应性,结果表明桔小实蝇中国和马来西亚种群之间的遗传关系极为相近,不存在生殖隔离,但杂交后代在繁殖力、孵化率、幼虫发育情况、高蛹期抗逆性等方面均显著高于其亲本种群,产卵管长度则介于亲本的马来西亚种群和中国种群之间。上述杂交种的适应性特征分析表明,杂交后代可能具有比亲本更强的传播潜力,因此,本研究结果对于桔小实蝇相异地理种群的检疫防控提出了新的挑战。 | 张灿 Muhammad Z Ahmed 马骏 武目涛 何日荣 梁帆 赵菊鹏 林莉 胡学难 Catharine Mannion Muhammad Ashfaq | 2018 | 环境昆虫学报2018，40，3： | 2 |
| 20 | Excitation of defect modes from the extended photonic band-gap structures of 1D photonic lattices显示文摘This paper stuides numerically the model equation in a one dimensional defective photonic lattice by modifying the potential function to a periodic function. It is found that defect modes (DMs) can be regarded as Bloch modes which are excited from the extended photonic band-gap structure at Bloch wave-numbers with k x = 0. The DMs for both positive and negative defects are considered in this method. | 周可雅 郭忠义 Muhammad Ashfaq Ahmad 刘树田 | 2010 | Chinese Physics B2010，19，1： | 2 |
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