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Magneto‑Dielectric Synergy and Multiscale Hierarchical Structure Design Enable Flexible Multipurpose Microwave Absorption and Infrared Stealth Compatibility

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Nano-Micro Letters 2025年第2期17卷 401-416页

作者： Chen Li Leilei Liang Baoshan Zhang Yi Yang Guangbin Ji School of Electronic Science and Engineering Nanjing UniversityNanjing 210093People’s Republic of China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Developing advanced stealth devices to cope with radar-infrared(IR)fusion detection and diverse application scenarios is increasingly demanded,which faces significant challenges due to conflicting microwave and IR cloaking mechanisms and functional integration ***,we propose a multiscale hierarchical structure design,integrating wrinkled MXene IR shielding layer and flexible Fe_(3)O_(4)@C/PDMS microwave absorption *** top wrinkled MXene layer induces the intensive diffuse reflection effect,shielding IR radiation signals while allowing microwave to pass ***,the permeable microwaves are assimilated into the bottom Fe_(3)O_(4)@C/PDMS layer via strong magneto-electric *** theoretical and experimental optimization,the assembled stealth devices realize a near-perfect stealth capability in both X-band(8–12 GHz)and long-wave infrared(8–14μm)wavelength ***,it delivers a radar cross-section reduction of−20 dB m^(2),a large apparent temperature modulation range(ΔT=70℃),and a low average IR emissivity of ***,the optimal device demonstrates exceptional curved surface conformability,self-cleaning capability(contact angle≈129°),and abrasion resistance(recovery time≈5 s).This design strategy promotes the development of multispectral stealth technology and reinforces its applicability and durability in complex and hostile environments.

关键词： Microwave absorption Radar-infrared compatible stealth Wrinkled MXene Magneto-dielectric synergy Multifunction

Two New Bisabolane Sesquiterpenes from Ligularia Thyrsoidea

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Chemical Research in Chinese Universities 1999年第1期15卷 69-71页

作者： LIAO Jian-chun YANG Li JIA Zhong-jian Department of Chemistry National Laboratory of Applied ChemistryLanzhou UniversityLanzhou730000

ＩｎＣｈｉｎａ，ｍｏｒｅｔｈａｎ２０Ｌｉｇｕｌａｒｉａｓｐｅｃｉｅｓ（Ｃｏｍｐｏｓｉｔａｅ）ｈａｖｅｂｅｅｎｕｓｅｄｆｏｒｆｏｌｋｍｅｄｉｃｉｎｅｓｗｉｔｈａｎｔｉｂｉｏｔｉｃ，ａｎｔｉｐｈｌｏｇｉｓｔｉｃａｎｄａｎ... 详细信息

ＩｎＣｈｉｎａ，ｍｏｒｅｔｈａｎ２０Ｌｉｇｕｌａｒｉａｓｐｅｃｉｅｓ（Ｃｏｍｐｏｓｉｔａｅ）ｈａｖｅｂｅｅｎｕｓｅｄｆｏｒｆｏｌｋｍｅｄｉｃｉｎｅｓｗｉｔｈａｎｔｉｂｉｏｔｉｃ，ａｎｔｉｐｈｌｏｇｉｓｔｉｃａｎｄａｎｔｉｔｕｍｏｒａｃｔｉｖｉｔｉｅｓ...

关键词： Ligularia thyrsoidea Bisabolane Sesquiterpene 2D NMR

L^(p) Boundedness of Fourier Integral Operators in the Class S_(0,0)

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Acta Mathematica Sinica,English Series 2022年第9期38卷 1551-1596页

作者： Ing-Lung HWANG Department of Mathematics "National Chung Cheng University of Taiwan"Chiayi County 621003China

We first prove the L~2-boundedness of a Fourier integral operator where it’s symbol a ∈S_(1/2,1/2)~0(R~n× R~n) and the phase function S is non-degenerate,satisfies certain conditions and may not be positively homogeneous in ξ-*** we use the above property,Paley’s inequality,covering lemma of Calderon and Zygmund etc.,and obtain the L~p-boundedness of Fourier integral operators if(1) the symbol a ∈ Λ_(k)^(m_(0)) and Supp a = E×R~n,with E a compact set of R~n(m_(0) =-|1/p-1/2|n,1n/2;2n/p),(2) the symbol a ∈ Λ_(0,k,k’)^(m_(0))(m_(0) =-|1/p-1/2|n,1n/2,k’>n/p;2n/p,k’>n/2) with the phase function S(x,ξ) = xξ + h(x,ξ),x,ξ ∈ R~n non-degenerate,satisfying certain conditions and ?ξ h ∈ S_(1,0)~0(R~n× R~n),or(3) the symbol a ∈ Λ_(0,k,k’)^(m_(0)),the requirements for m_(0),k,k’ are the same as in(2),and ?_(ξ)h is not in S_(1,0)~0(R~n× R~n) but the phase function S is non-degenerate,satisfies certain conditions and is positively homogeneous in ξ-variables.

关键词： Fourier integral operator L^(p)-boundedness

Secure and Efficient Mutual Authentication Scheme for NFC Mobile Devices

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Journal of Electronic Science and Technology 2017年第3期15卷 240-245页

作者： You-Han Tung Wen-Shenq Juang Department of Information Management National Kaohsiung First University of Science and Technology Kaohsiung 824

As the technology of mobile devices spreads fast,the price of mobile devices is getting *** of the people have mobile devices,and these devices have the technology of near field communication（NFC）.With the long time development and research,the mobile devices use NFC technology on the payment and authentication applications,and replace the smartcard,the access control card,and the credit card by using the card emulation *** helps the development of NFC *** recent years,more and more users begin using NFC technology on mobile payment and *** researches have proposed the related NFC authentication protocols,but their schemes are still lack of some security properties and functions,which are necessary for NFC authentication *** this paper,we propose a secure and efficient NFC authentication scheme between two NFC devices by the help of the authentication server that provides mutual authentication.

关键词： Index Terms--Authentication protocol informationsecurity mutual authentication near fieldcommunication (NFC)

Gas-phase hydrogenation influence on defect behavior in titanium-based hydrogen-storage material

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Progress in Natural Science:Materials International 2017年第1期27卷 105-111页

作者： Roman S.Laptev Viktor N.Kudiiarov Yuri S.Bordulev Andrey A.Mikhaylov Andrey M.Lider Department of General Physics Institute of Physics and Technology National Research Tomsk Polytechnic University

Titanium and its alloys are promising materials for hydrogen storage. However, hydrogen penetration accompanies the exploitation of hydrogen storage alloys. In particular, hydrogen penetration and accumulation in titanium alloys changes their mechanical properties. Therefore, the research works of such materials are mainly focused on improving the reversibility of hydrogen absorption-liberation processes, increasing the thermodynamic characteristics of the alloys, and augmenting their hydrogen storage capacity. In the process of hydrogenation-dehydrogenation, the formed defects both significantly reduce hydrogen storage capacity and can also be used to create effective traps for hydrogen. Therefore, the investigation of hydrogen interaction with structural defects in titanium and its alloys is very important. The present work, the hydrogen-induced formation of defects in the alloys of commercially pure titanium under temperature gas-phase hydrogenation（873 K） has studied by positron lifetime spectroscopy and Doppler broadening spectroscopy. Based on the evolution of positron annihilation parameters τ_f, τd, their corresponding intensities If, Idand relative changes of parameters S/S0and W/W0, the peculiarities of hydrogen interaction with titanium lattice defects were investigated in a wide range of hydrogen concentrations from 0.8at% to 32.0at%.

关键词： Titanium Hydrogen Lattice defects Positron annihilation Positron lifetime Doppler broadening

Inversion of two-dimensional tidal open boundary conditions of M_2 constituent in the Bohai and Yellow Seas

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Chinese Journal of Oceanology and Limnology 2012年第5期30卷 868-875页

作者：曹安州郭筝吕咸青 Laboratory of Physical Oceanography Ocean University of China national Marine Data and Information Service

Two-dimensional tidal open boundary conditions of the M2 constituent in the Bohai and Yellow Seas(BYS) have been estimated by assimilating T/P altimeter *** inversion,independent point(IP) strategy was used,in which several IPs on the open boundary is assumed,values at these IPs can be optimized with an adjoint method,and those at other grid points are determined by linearly interpolating the values at *** reasonability and feasibility of the model are tested by ideal twin *** the practical experiment(PE) after assimilation,the cost function may reach 1% or less of its initial *** absolute errors in amplitude and phase can be less than 5 cm and 5°,respectively,and the obtained co-chart can show the character of the M2 constituent in the *** results of the PE indicate that using only two IPs on the open boundary can yield better simulated results.

关键词： two-dimensional adjoint method T/P altimeter open boundary conditions independent points

Decomposition Properties of Quantum Discord

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Communications in Theoretical Physics 2016年第4期65卷 441-446页

作者： Sunho Kim 武俊德 Minhyung Cho Department of Mathematics Zhejiang University Department of Applied Mathematics Kumoh National Institute of Technology

The quantum discord was introduced by Ollivier,Zurek,Henderson,and Vedral as an indicator of the degree of quantumness of mixed *** this paper,we provide a decomposition condition for quantum ***,we show that under the condition,the quantum correlations between the quantum systems can be captured completely by the entanglement ***,we present examples of our conclusions.

关键词： quantum state quantum measurement quantum discord

Exploring changes of land use and mangrove distribution in the economic area of Sidoarjo District,East Java using multi-temporal Landsat images

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Information Processing in Agriculture 2017年第4期4卷 321-332页

作者： Norida Maryantika Chinsu Lin Dept.of Forestry and Natural Resources National Chiayi UniversityTaiwan

Remotely sensed data are capable of providing spatial and temporal information on land use land cover(LULC)over a large extent of *** Sidoarjo District in East Java Province has recently been extensively explored for economic development *** paper examines the use of multi-temporal Landsat images in deriving information for LULC maps,changes of land development and natural ecosystems such as mangrove forest within particular economic reform *** suggest a minimum accuracy(baseline)for LULC mapping using Landsat multispectral reflectance data of 74% for the overall accuracy(OA)and 0.70 for the kappa coefficient of agreement(kappa).On average an acceptable accuracy(OA=88% and kappa=0.86)can be achieved by integrating multispectral reflectance and green normalized difference vegetation index(GNDVI)to support vector machine *** economic reform in the Sidoarjo District made a significant change to LULC and mangrove *** 1995 to 2015,25% of crop land and 15% of bare land changed to become built-up areas,and 8% of wetland and 22% of mangroves changed to crop land.A remarkable decrease of mangrove forest occurred in the interior land along the river systems over the whole ***,the coastal mangroves areas saw a significant increase due to the Lumpur Sidoarjo(LUSI)-caused mud flow sediments near the estuary of the *** impact of extensive economic activities and development on the natural mangrove forests was partially compensated for by the LUSI events and also newly developed local community oriented conservative management.

关键词： Mangroves Land use land cover changes Support vector machine(SVM) Vegetation index Lumpur Sidoarjo(LUSI)

Two optimization algorithms for solving robotics inverse kinematics with redundancy

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控制理论与应用（英文版） 2010年第2期8卷 166-175页

作者： Jianxin XU, Wei WANG, Yuanguang SUN (Department of Electrical and Computer Engineering, national university of Singapore, Singapore 117576) Department of Electrical and Computer Engineering National University of Singapore Singapore Singapore

The kinematic redundancy in a robot leads to an infinite number of solutions for inverse kinematics, which implies the possibility to select a 'best' solution according to an optimization criterion. In this paper, two optimization objective functions are proposed, aiming at either minimizing extra degrees of freedom (DOFs) or minimizing the total potential energy of a multilink redundant robot. Physical constraints of either equality or inequality types are taken into consideration in the objective functions. Since the closed-form solutions do not exist in general for highly nonlinear and constrained optimization problems, we adopt and develop two numerical methods, which are verified to be effective and precise in solving the two optimization problems associated with the redundant inverse kinematics. We first verify that the well established trajectory following method can precisely solve the two optimization problems, but is computation intensive. To reduce the computation time, a sequential approach that combines the sequential quadratic programming and iterative Newton-Raphson algorithm is developed. A 4-DOF Fujitsu Hoap-1 humanoid robot arm is used as a prototype to validate the effectiveness of the proposed optimization solutions.

关键词： Inverse kinematics Redundant robot Objective function Optimization Numerical approach