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Cyclic beamforming using fractional Fourier transform domain cyclostationarity

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High Technology Letters 2011年第1期17卷 57-63页

作者： muhammad ishtiaq Ahmad Liu Zhiwen Xu Yougen School of Information ＆ Electronics Beijing Institute of Technology Beijing 100081 P. R. China

A minimum mean-squared error （MSE） beamforming algorithm employing the optimum fractional Fourier transform （Opt-FrFT） domain second-order cyclostationarity is proposed. This method can efficiently filter out the compact desired chirp signal, with a consequence that the cyclically uncorrelated interferences and stationary （colored） Gaussian noise are greatly suppressed in the Opt- FrFT domain. This improves the MSE minimization cyclic beamformer by reducing effectively the Opt-FrFY domain signal-noise cross terms in the presence of finite data length de-correlation operation. Simulation results show that the new method works well under a wide range of signal-to-noise ratio （SNR） and signal-to-interference ratio （SIR）.

关键词： beamforming fractional Fourier transform chirp signal cyclostationarity

On the stacking fault forming probability and stacking fault energy in carbon-doped 17 at%Mn steels via transmission electron microscopy and atom probe tomography

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Journal of Materials Science & Technology 2022年第20期115卷 177-188页

作者： Hyo Ju Bae Kwang Kyu Ko muhammad ishtiaq Jung Gi Kim Hyokyung Sung Jae Bok Seol Department of Materials Engineering and Convergence Technology Center for K-metalGyeongsang National University(GNU)Jinju 52828South Korea

Assessing the stacking fault forming probability(P_(sf)) and stacking fault energy(SFE)in medium-or highMn base structural materials can anticipate and elucidate the microstructural evolution before and after ***,these two parameters have been determined from theoretical calculations and empirical ***,the estimation of SFE values in Fe–Mn–C ternary systems is a longstanding debate due to the complicated nature of carbon:that is,whether the carbon doping indeed plays an important role in the formation of stacking faults;and how the amount of carbon atoms exist at grain boundaries or at internal grains with respect to the nominal carbon doping ***,the use of atom probe tomography and transmission electron microscopy(TEM)unveils the influence of carbondoping contents on the structural properties of dual-phase Fe–17 Mn–x C(x=0–1.56 at%)steels,such as carbon segregation free energy at grain boundaries,carbon concentration in grain interior,interplanar D-spacings,and mean width of intrinsic stacking faults,which are essential for SFE *** next determined the Psfvalues by two different methods,viz.,reciprocal-space electron diffraction measurements and stacking fault width measurements in real-space TEM ***,SFEs in the Fe–17 Mn–x C systems were calculated on the basis of the generally-known SFE *** found that the high amount of carbon doping gives rise to the increased SFE from 8.6 to 13.5 m J/m^(2)with non-linear *** SFE trend varies inversely with the mean width of localized stacking faults,which pass through both other stacking faults and pre-existingε-martensite plates without much difficulty at their intersecting *** high amount of carbon doping acts twofold,through increasing the segregation free energy(due to more carbon at grain boundaries)and large lattice expansion(due to increased soluble carbon at internal grains).The experimental data obtained here strengthens the composition-

关键词： Stacking fault formation probability Stacking fault energy High-Mn steel Electron diffraction

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Analysis of b→cτν¯_(τ)anomalies using weak effective Hamiltonian with complex couplings and their impact on various physical observables

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Chinese Physics C 2024年第8期48卷 56-75页

作者： muhammad Arslan Tahira Yasmeen Saba Shafaq ishtiaq Ahmed muhammad Jamil Aslam Department of Physics Quaid-i-Azam UniversityIslamabad 45320Pakistan Department of Physics International Islamic UniversityIslamabad 44000Pakistan National Center for Physics Islamabad 44000Pakistan

Recently,the experimental measurements of the branching ratios and different polarization asymmetries for processes occurring through flavor-changing-charged current(b→cτν¯_(τ))transitions by BABAR,Belle,and LHCb have revealed some significant differences from the corresponding Standard Model(SM)*** has triggered an interest to search for physics beyond the SM in the context of various new physics(NP)models and using the model-independent weak effective Hamiltonian(WEH).Assuming left-handed neutrinos,we add the dimension-six vector,(pseudo-)scalar,and tensor operators with complex Wilson coefficients(WCs)to the SM *** 60%,30%,and 10%constraints resulting from the branching ratio of B_(c)→τν¯_(τ),we reassess the parametric space of these new physics WCs accommodating the current anomalies based on the most recent HFLAV data of R_(τ/μ,e)(D)and R_(τ/μ,e)(D^(*))and Belle data of F_(L)(D^(*))and P_(τ)(D^(*)).We find that the allowed parametric region of left-handed scalar couplings strongly depends on the constraints of the B_(c)→τν¯_(τ)branching ratio,and the maximum pull from the SM predictions results from the<60%branching ratio ***,the parametric region changes significantly if we extend the analysis by adding LHCb data of R_(τ/μ)(J/ψ)and R_(τ/ℓ)(Λ_(c)).Furthermore,due to the large uncertainties in the measurements of R_(τ/μ)(J/ψ)and R_(τ/ℓ)(X_(c)),we derive the sum rules which complement them with R_(τ/μ,e)(D)and R_(τ/μ,e)(D^(*)).Using the best-fit points of the new complex WCs along with the latest measurements of R_(τ/μ,e)(D(^(*))),we predict the numerical values of the observable R_(τ/ℓ)(Λ_(c)),R_(τ/μ)(J/ψ),and R_(τ/ℓ)(X_(c))from the sum *** simultaneous dependence of abovementioned physical observables on the NP WCs is established by plotting their correlation with R_(D) and R_(D^(*)),which are useful to discriminate between various NP *** find that the most significant impact of NP results from the WC C^(S)_(L)=4C^(T).Fi

关键词： B meson anomalies new physics complex coupling HFLAV

Unordered rule discovery using Ant Colony Optimization

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Science China(Information Sciences) 2014年第9期57卷 189-203页

作者： KHAN Salabat BAIG Abdul Rauf ALI Armughan HAIDER Bilal KHAN Farman Ali DURRANI Mehr Yahya ishtiaq muhammad Department of Computer Science COMSATS Institute of Information TechnologyAttock CampusPakistan Department of Computer Science National University of Computer and Emerging SciencesIslamabadPakistan Al Imam Mohammad Ibn Saud Islamic University (IMSIU) College of Computer and Information SciencesRiyadhSaudi Arabia

In this article,a novel unordered classification rule list discovery algorithm is presented based on Ant Colony Optimization(ACO).The proposed classifier is compared empirically with two other ACO-based classification techniques on 26 data sets,selected from miscellaneous domains,based on several performance *** opposed to its ancestors,our technique has the flexibility of generating a list of IF-THEN rules with unrestricted *** makes the generated classification model more comprehensible and easily *** results indicate that the performance of the proposed method is statistically significantly better as compared with previous versions of AntMiner based on predictive accuracy and comprehensibility of the classification model.

关键词： classification ant colony optimization data mining unordered rule set comprehensibility pattern recognition

Clematis huchouensis Tamura: a traditional Chinese herbal medicine and its quality control by high performance liquid chromatography fingerprint technique

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Clematis huchouensis Tamura: a traditional Chinese herbal me...

Modelling of debris-flow susceptibility and propagation: a case study from Northwest Himalaya

中国化学会第二十五届学术年会

作者： muhammad ishtiaq Pharmaceutical Informatics Institute Zhejiang UniversityNo. 38 Zhe da Road Hangzhou 310027 P. R. China

A simple, precise and reliable high performance liquid chromatography (HPLC) protocol was demarcated and validated for the study of fingerprint chromatograms of extracts from the whole plant of Clemat

关键词： Tian Mu Shan Traditional Chinese medicines, Clematis huchouensis Tamura Rutin HPLC Flavonoids

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Journal of Mountain Science 2024年第1期21卷 200-217页

作者： Hamza DAUD Javed Iqbal TANOLI Sardar muhammad ASIF muhammad QASIM muhammad ALI Junaid KHAN Zahid Imran BHATTI ishtiaq Ahmad Khan JADOON Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China Department of Earth Sciences COMSATS University IslamabadAbbottabad Campus 22010Pakistan Department of Earth Sciences Sultan Qaboos UniversityAl-KhoudMascat 123Oman Faculty of Engineering China University of Geosciences(Wuhan)Wuhan 430074China Department of Earth Sciences Abbottabad University of Science and TechnologyHavelian 22500Pakistan

The geological and geographical position of the Northwest Himalayas makes it a vulnerable area for mass movements particularly landslides and debris flows. Mass movements have had a substantial impact on the study area which is extending along Karakorum Highway(KKH) from Besham to Chilas. Intense seismicity, deep gorges, steep terrain and extreme climatic events trigger multiple mountain hazards along the KKH, among which debris flow is recognized as the most destructive geohazard. This study aims to prepare a field-based debris flow inventory map at a regional scale along a 200 km stretch from Besham to Chilas. A total of 117 debris flows were identified in the field, and subsequently, a point-based debris-flow inventory and catchment delineation were performed through Arc GIS analysis. Regional scale debris flow susceptibility and propagation maps were prepared using Weighted Overlay Method(WOM) and Flow-R technique sequentially. Predisposing factors include slope, slope aspect, elevation, Topographic Roughness Index(TRI), Topographic Wetness Index(TWI), stream buffer, distance to faults, lithology rainfall, curvature, and collapsed material layer. The dataset was randomly divided into training data(75%) and validation data(25%). Results were validated through the Receiver Operator Characteristics(ROC) curve. Results show that Area Under the Curve(AUC) using WOM model is 79.2%. Flow-R propagation of debris flow shows that the 13.15%, 22.94%, and 63.91% areas are very high, high, and low susceptible to debris flow respectively. The propagation predicated by Flow-R validates the naturally occurring debris flow propagation as observed in the field surveys. The output of this research will provide valuable input to the decision makers for the site selection, designing of the prevention system, and for the protection of current infrastructure.

关键词： North Pakistan Debris flow Flow-R Propagation Susceptibility mapping Debris-flow inventory Weighted Overlay Method

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Advanced Automatic Pumping Station with Canal Water Level Remote Control System Using ABB PLC Based on FLC

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Advanced Automatic Pumping Station with Canal Water Level Re...

作者： ishtiaq muhammad 兰州理工大学

学位级别：硕士

本论文主要研究动态模型,模拟与高级自动化控制水泵站。使用基于模糊逻辑控制器的ABB PLC的渠道远程控制系统。该系统的设计使用范围是水位(水渠或河流)较低或者传统的灌溉系统无法正常工作的情况下。该系统可以通过水库门依据水位的最... 详细信息

本论文主要研究动态模型,模拟与高级自动化控制水泵站。使用基于模糊逻辑控制器的ABB PLC的渠道远程控制系统。该系统的设计使用范围是水位(水渠或河流)较低或者传统的灌溉系统无法正常工作的情况下。该系统可以通过水库门依据水位的最高限和最低限来控制水位,也可以通过增加或者减少水泵的运转速度来控制水渠的水位。通过两个不同的控制器来实现系统的全自动化;一个控制器依据水库的水量限制对水库门实现自动操作,另一个控制器自动操作两个泵的运转速度来控制水渠的水位。为了能够对整个系统实现控制,监视,和准确的时间控制,安装HMI(人工干涉器—CP 405)就可以显示水库的输入水量(m3/秒),和输出水量(m3/秒),水库门的状态(打开或关闭),水库的水位(m),水泵的速度(rpm),水泵的输出电压(V),电流(A)和扭矩(%),水渠的流量和水位(相对深度)。最高和最低的水量限制以及水渠的水位也可通过它来实现改变。所有的参数走势都可以通过走势图来显示出来。渠道水位可以根据设计的方程计算出来。通过水位高度计算渠道水位这一方法是以PLC和渠道水位高度之间的GPRS交互系统为依据的。在矩阵实验室和动态仿真模型内设计了应用型模糊逻辑系统,因此可以通过OPC实现与PLC的交互。数字控制器PLC(AC500 PM556-ETH)通过HMI输入数据(水库的水量限制以及渠道水位的设置),并将这些数据通过OPC服务器传送到模糊逻辑控制器。OPC服务器是通过调节水泵运转速度来控制调节水库门状态并控制水量限制和渠道水位的装置。PLC从控制器那里接收到信息之后开始运作。模拟结果显示该系统无论在自动状态还是人工操作状态都可以有效地运作。

关键词：渠道水位模糊逻辑控制水自动库自动

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万达购物中心性能化防火设计研究

万达购物中心性能化防火设计研究

作者： muhammad ishtiaq Akhtar 中国科学技术大学

学位级别：硕士

零售商场常面临着包括火灾在内的一系列风险,购物中心也不例外。许多人光顾的封闭购物中心若发生火灾,惊慌失措的人群会互相推挤地逃离这些燃烧和烟雾弥漫的地方,导致许多人死亡。据统计,火灾中大多数受害者不是由火灾直接导致的死亡,... 详细信息

零售商场常面临着包括火灾在内的一系列风险,购物中心也不例外。许多人光顾的封闭购物中心若发生火灾,惊慌失措的人群会互相推挤地逃离这些燃烧和烟雾弥漫的地方,导致许多人死亡。据统计,火灾中大多数受害者不是由火灾直接导致的死亡,而是烟雾能见度低、有毒气体窒息所致。本文针对火灾烟气能见度和人员疏散概率对中国南宁市的某高层购物中心(商场)展开了算法研究,分析了 38个火灾模拟案例和相应的3个疏散案例。我们阐述了性能化设计(PBD)的基本原则概念框架,使用三个软件程序,即:PATHFINDER、FDS和PyroSim开展了研究。在模拟中,考虑了三种条件,一是自然排风窗开闭状态,二是窗口故障状态,三是水喷淋开启状态。我们首先对窗口的开闭状态进行了研究,发现当窗户打开时,建筑内的三层楼均在相当长的一段时间内完全无烟,而三楼步行街的楼梯区域不能完全无烟。同时,我们还研究了在正常和拥挤条件下的安全疏散时间。通过分析安全时间曲线,我们揭示了烟雾在建筑中扩散的速度、烟雾的能见度,以及烟雾从一层流动到另一层的动力学过程。仿真结果可为建筑设计和人员安全疏散提供参考。

关键词：性能化设计火灾动力学模拟器 PATHFINER 烟雾能见度安全时间曲线

Analysis of b→cτ■ anomalies using weak effective Hamiltonian with complex couplings and their impact on various physical observables

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Chinese Physics C 2024年第8期 59-78页

作者： muhammad Arslan Tahira Yasmeen Saba Shafaq ishtiaq Ahmed muhammad Jamil Aslam Department of Physics Quaid-i-Azam University Department of Physics International Islamic University National Center for Physics

Recently,the experimental measurements of the branching ratios and different polarization asymmetries for processes occurring through flavor-changing-charged current（b→cτvτ）transitions by BABAR,Belle,and LHCb have revealed some significant differences from the corresponding Standard Model（SM） *** has triggered an interest to search for physics beyond the SM in the context of various new physics（NP） models and using the model-independent weak effective Hamiltonian（WEH）.Assuming left-handed neutrinos,we add the dimension-six vector,（pseudo-）scalar,and tensor operators with complex Wilson coefficients（WCs） to the SM *** 60%,3 0%,and 10% constraints resulting from the branching ratio of Bc→τvτ,we reassess the parametric space of these new physics WCs accommodating the current anomalies based on the most recent HFLAV data of Rτ/μ,e（D） and Rτ/μ,e（D*） and Belle data of FL（D*） and Pτ（D*）.We find that the allowed parametric region of lefthanded scalar couplings strongly depends on the constraints of the Bc→τvτbranching ratio,and the maximum pull from the SM predictions results from the <60% branching ratio ***,the parametric region changes significantly if we extend the analysis by adding LHCb data of Rτ/μ（J/ψ） and Rτ/l（Λc）.Furthermore,due to the large uncertainties in the measurements of Rτ/μ（J/ψ） and Rτ/l（Xc）,we derive the sum rules which complement them with Rτ/μ,e（D） and Rτ/μ,e（D*）.Using the best-fit points of the new complex WCs along with the latest measurements of Rτ/μ,e(D（*）),we predict the numerical values of the observable Rτ/l（Λc）,Rτ/μ（J/ψ）,and Rτ/l（Xc） from the sum *** simultaneous dependence of abovementioned physical observables on the NP WCs is established by plotting their correlation with RDand RD*,which are useful to discriminate between various NP *** find that the most significant impact of NP results from the WC CLS=***,we study the impact of these NP couplings on various angular and CP triple product asym

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