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Design Framework of Unsourced Multiple Access for 6G Massive IoT

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China Communications 2024年第1期21卷 1-12页

作者： Chunlin Yan Siying Lyu Sen Wang Yuhong Huang xiaodong xu China Mobile Communication Research institute Beijing 100053China ZGC institute of Ubiquitous-x Innovation and Applications Beijing 100080China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

In this paper,ambient IoT is used as a typical use case of massive connections for the sixth generation(6G)mobile communications where we derive the performance requirements to facilitate the evaluation of technical solutions.A rather complete design of unsourced multiple access is proposed in which two key parts:a compressed sensing module for active user detection,and a sparse interleaver-division multiple access(SIDMA)module are simulated side by side on a same platform at balanced signal to noise ratio(SNR)operating points.With a proper combination of compressed sensing matrix,a convolutional encoder,receiver algorithms,the simulated performance results appear superior to the state-of-the-art benchmark,yet with relatively less complicated processing.

关键词： channel coding compressed sensing massive Internet-of-Things(IoT) sparse interleaverdivision multiple access(SIDMA) the sixth generation(6G)mobile communications unsourced multiple access

Accurate diagnosis of severe coronary stenosis based on resting magnetocardiography: a prospective, single-center, cross-sectional analysis

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Journal of Geriatric Cardiology 2024年第4期21卷 407-420页

作者： Jian-Guo CUI Feng TIAN Yu-Hao MIAO Qin-Hua JIN Ya-Jun SHI Li LI Meng-Jun SHEN xiao-Ming xIE Shu-Lin ZHANG Yun-Dai CHEN School of medicine Nankai UniversityTianjinChina Senior Department of Cardiology the Sixth Medical CenterChinese PLA General HospitalBeijingChina Joint Laboratory of Bioimaging Technology and Applications SAS-SIM-IT&MEDIShanghaiChina Shanghai institute of Microsystem and Information Technology Chinese Academy of SciencesShanghaiChina

OBJECTIVE To evalu ate the role of resting magnetocardiography in identifying seve re coronary artery stenosis in patients with suspected coronary artery disease.METHODS A total of 513 patients with angina symptoms were included and divided into two groups based on the extent of coronary artery disease determined by angiography:the non-severe coronary stenusis group(xhibited an area under the curve of 0.845(95% CI:0.798-0.892).The sensitivity,specificity,PPV,NPV,and accuracy were 84.3%,73.8%,92.6%,54.6%,and 82.1%;respectively.Calibration curves demonstrate d excellent agreement between the nomogram prediction and actual observation.The decision curve analysis showed that the c ombine d model provided greater net benefit compared to the magnetocardingraphy model.CONCLUSIONS The novel quantitative MFM parameters

关键词： coronary stenosis specificity

Bioinspired Tactile Sensation Based on Synergistic Microcrack-Bristle Structure Design toward High Mechanical Sensitivity and Direction-Resolving Capability

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Research 2024年第1期2023卷 611-624页

作者： Yiqun Zhang Qi Liu Wenjuan Ren Yangyang Song Hua Luo Yangyang Han Liang He xiaodong Wu Zhuqing Wang School of Mechanical Engineering Sichuan UniversityChengdu 610065China Med+x Center for Manufacturing West China HospitalSichuan UniversityChengdu 610041China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu 610065China

Natural tactile sensation is complex,which involves not only contact force intensity detection but also the perception of the force direction,the surface texture,and other mechanical parameters.Nevertheless,the vast majority of the developed tactile sensors can only detect the normal force,but usually cannot resolve shear force or even distinguish the directions of the force.Here,we present a new paradigm of bioinspired tactile sensors for resolving both the intensity and the directions of mechanical stimulations via synergistic microcrack-bristle structure design and cross-shaped configuration engineering.The microcrack sensing structure gives high mechanical sensitivity to the tactile sensors,and the synergistic bristle structure further amplifies the sensitivity of the sensors.The cross-shaped configuration engineering of the synergistic microcrack-bristle structure further endows the tactile sensors with good capability to detect and distinguish the directions of the applied mechanical forces.The as-fabricated tactile sensors exhibit a high sensitivity(25.76 N^(−1)),low detection limit(5.4 mN),desirable stability(over 2,500 cycles),and good capability to resolve both mechanical intensity and directional features.As promising application scenarios,surface texture recognition and biomimetic path explorations are successfully demonstrated with these tactile sensors.This newly proposed tactile sensation strategy and technology have great potential applications in ingenious tactile sensation and construction of various robotic and bionic prostheses with high operational dexterity.

关键词： crack sensation directions

Applications of cnoidal and snoidal wave solutions via optimal system of subalgebras for a generalized extended (2+1)-D quantum Zakharov-Kuznetsov equation with power-law nonlinearity in oceanography and ocean engineering

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Journal of Ocean Engineering and Science 2024年第2期9卷 126-153页

作者： Oke Davies Adeyemo International institute for Symmetry Analysis and Mathematical Modelling Department of Mathematical SciencesNorth-West UniversityMafikeng CampusPrivate Bag X 2046Mmabatho 2735Republic of South Africa

The nonlinear evolution equations have a wide range of applications,more precisely in physics,biology,chemistry and engineering fields.This domain serves as a point of interest to a large extent in the world’s mathematical community.Thus,this paper purveys an analytical study of a generalized extended(2+1)-dimensional quantum Zakharov-Kuznetsov equation with power-law nonlinearity in oceanography and ocean engineering.The Lie group theory of differential equations is utilized to compute an optimal system of one dimension for the Lie algebra of the model.We further reduce the equation using the subalgebras obtained.Besides,more general solutions of the underlying equation are secured for some special cases of n with the use of extended Jacobi function expansion technique.Consequently,we secure new bounded and unbounded solutions of interest for the equation in various solitonic structures including bright,dark,periodic(cnoidal and snoidal),compact-type as well as singular solitons.The applications of cnoidal and snoidal waves of the model in oceanography and ocean engineering for the first time,are outlined with suitable diagrams.This can be of interest to oceanographers and ocean engineers for future analysis.Furthermore,to visualize the dynamics of the results found,we present the graphic display of each of the solutions.Conclusively,we construct conservation laws of the understudy equation via the application of Noether’s theorem.

关键词： A generalized extended(2+1)-dimensional quantum Zakharov-Kuznetsov equation Lie point symmetries Optimal system of subalgebras Cnoidal and snoidal waves Extended Jacobi function expansion technique Conservation laws

FSS: algorithm and neural network accelerator for style transfer

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Science China(Information Sciences) 2024年第2期67卷 253-266页

作者： Yi LING Yujie HUANG Yujie CAI Zhaojie LI Mingyu WANG Wenhong LI xiaoyang ZENG State Key Laboratory of ASIC & System Fudan University Shanghai Explore x Technology Co. Ltd.

Neural networks(NNs), owing to their impressive performance, have gradually begun to dominate multimedia processing. For resource-constrained and energy-sensitive mobile devices, an efficient NN accelerator is necessary. Style transfer is an important multimedia application. However, existing arbitrary style transfer networks are complex and not well supported by current NN accelerators, limiting their application on mobile devices. Moreover, the quality of style transfer needs improvement. Thus, we design the Fast Style system(FSS), where a novel algorithm and an NN accelerator are proposed for style transfer. In FSS, we first propose a novel arbitrary style transfer algorithm, Fast Style. We propose a light network that contributes to high quality and low computational complexity and a prior mechanism to avoid retraining when the style changes. Then, we redesign an NN accelerator for Fast Style by applying two improvements to the basic NVIDIA deep learning accelerator(NVDLA) architecture. First, a flexible dat FSM and wt FSM are redesigned to enable the original data path to perform other operations(including the GRAM operation)by software programming. Moreover, statistics and judgment logic are designed to utilize the continuity of a video stream and remove the data dependency in the instance normalization, which improves the accelerator performance by 18.6%. The experimental results demonstrate that the proposed Fast Style can achieve higher quality with a lower computational cost, making it more suitable for mobile devices. The proposed NN accelerator is implemented on the xilinx VCU118 FPGA under a 180-MHz clock. Experimental results show that the accelerator can stylize 512×512-pixel video with 20 FPS, and the measured performance reaches up to 306.07 GOPS. The ASIC implementation in TSMC 28 nm achieves about 22 FPS in the case of a 720-p video.

关键词： neural network accelerator style transfer neural network deep learning

Rhodium-Catalyzed Asymmetric Transfer Hydrogenation of Heterocyclic Diaryl Ketones:Facile Access to Key Intermediate of Baloxavir

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Chinese Journal of Chemistry 2024年第1期42卷 43-47页

作者： Li Wang Renwei xiao Jingyuan Song Long-Sheng Zheng Qiwei Lang Gen-Qiang Chen xumu Zhang Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis Department of Chemistryand Medi-PingshanSouthern University of Science and TechnologyShenzhenGuangdong 518000China Academy for Advanced Interdisciplinary Studies Southern Universityof Science and TechnologyShenzhenGuangdong 518000China Chemistry and Chemical Engineering Guangdong Laboratory ShantouGuangdong 515031China

Transition metal-catalyzed asymmetric transfer hydrogenation has been proven to be a powerful approach for the synthesis of chiral alcohols.Herein,a highly efficient and enantioselective transfer hydrogenation of dibenzoheptaheterocyclic ketones catalyzed by an arene-tethered TsDPEN-based Rh(ll)catalyst has been successfully developed,and a variety of dibenzoheptaheterocyclic ketones were reduced by a 1/1 mixture of formic acid and DBU(1,8-diazabicyclo[5.4.0]undec-7-ene)with high yields and enantioselectivities.With this method,the asymmetric reduction of 7,8-difluorodibenzo[b,e]thiepin-11(6H)-one has been realized,providing the key intermediate of baloxavir marboxil with>99% yield and>99% ee at a substrate/catalyst molar ratio of 1000.

关键词： Asymmetric transfer hydrogenation Baloxavir Chiral alcohol Enantioselectivity Heterocyclic diaryl ketone Rhodium(Ⅱ)

Decohesion of graphene from a uniaxially-stretched substrate:Failure analysis of a frictional adhesive interface

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Friction 2024年第3期12卷 510-521页

作者： Bo PENG Chaochen xU Qingao WANG Pei ZHAO xiqiao FENG Qunyang LI AML Department of Engineering MechanicsTsinghua UniversityBeijing 100084China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing 100084China Center for x-Mechanics and institute of Applied Mechanics Zhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power and M

Composite structures consisting of two-dimensional(2D)materials deposited on elastic substrates have a wide range of potential applications in flexible electronics.For such devices,robust 2D film/substrate interfacial adhesion is essential for their reliable performance when subjected to external thermal and mechanical loads.To better understand the strength and failure behavior of the 2D film/substrate interfaces,two types of graphene/polymer samples with distinct interfacial adhesion properties are fabricated and tested by uniaxially stretching the substrates.Depending on the interfacial adhesion,two drastically different debonding rates are observed,i.e.,rapid snap-through debonding and more progressive crack propagation.Motivated by the experimental observation,we propose an improved shear-lag model with a trapezoidal-shaped cohesive zone to derive an analytical solution for the decohesion behavior.The theoretical model reveals that the decohesion behavior of the frictional adhesive interface is governed by three dimensionless parameters.Particularly,the dimensionless length of the film essentially determines the decohesion rate;while the other two parameters affect the critical substrate strain to initiate debonding.By fitting the experimental data with the theoretical model,the intrinsic adhesion properties of the two samples are obtained with physically meaningful values.This work offers an analytical solution to describing the decohesion behavior of general thin film/substrate systems with a frictional adhesive interface,which is beneficial for characterizing and optimizing the mechanical properties of various thin film/polymer devices.

关键词： film/substrate systems adhesion frictional sliding interface decohesion cohesive-zone model

A pH-responsive nanoparticle delivery system containing dihydralazine and doxorubicin-based prodrug for enhancing antitumor efficacy

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Aggregate 2024年第1期5卷 436-450页

作者： Lianxue Zhang Jianxiang Huang Damiano Buratto Panli Han Zaixing Yang Ruhong Zhou institute of Quantitative Biology Shanghai Institute for Advanced StudyCollege of Life SciencesZhejiang UniversityHangzhouChina State Key Laboratory of Radiation medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)Soochow UniversitySuzhouChina Cancer Center Zhejiang UniversityHangzhouChina Department of Chemistry Columbia UniversityNew YorkNew YorkUSA

The efficacy of nanoparticle(NP)-based drug delivery technology is hampered by aberrant tumor stromal microenvironments(TSMs)that hinder NP transportation.Therefore,the promotion of NP permeation into deep tumor sites via the regulation of tumor microenvironments is of critical importance.Herein,we propose a potential solution using a dihydralazine(HDZ)-loaded nanoparticle drug delivery system containing a pH-responsive,cyclic RGD peptide-modified prodrug based on doxorubicin(cRGD-Dex-DOx).With a combined experimental and theoretical approach,we find that the designed NP system can recognize the acid tumor environments and precisely release the encapsulated HDZ into tumor tissues.HDZ can notably downregulate the expression levels of hypoxia-inducible factor 1α(HIF1α),α-smooth muscle actin,and fibronectin through the dilation of tumor blood vessels.These changes in the TSMs enhance the enrichment and penetration of NPs and also unexpectedly promote the infiltration of activated T cells into tumors,suggesting that such a system may offer an effective“multifunctional therapy”through both improving the chemotherapeutic effect and enhancing the immune response to tumors.In vivo experiments on 4T1 breast cancer bearing mice indeed validate that this therapy has the most outstanding antitumor effects over all the other tested control regimens,with the lowest side effects as well.

关键词： antitumor dihydralazine drug delivery system tumor stromal microenvironment vasculature

Polyethylene interfacial dielectric layer for organic semiconductor single crystal based field-effect transistors

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Chinese Chemical Letters 2024年第4期35卷 431-435页

作者： Min Chen Boyu Peng xuyun Guo Ye Zhu Hanying Li Department of Polymer Science and Engineering MOE Key Laboratory of Macromolecular Synthesis and FunctionalizationInternational Research Center for X PolymersShanxi-Zheda Institute of Advanced Materials and Chemical EngineeringZhejiang UniversityHangzhou 310027China Department of Applied Physics Research Institute for Smart EnergyThe Hong Kong Polytechnic UniversityHong Kong 999077China

Organic semiconductor single crystals(OSSCs) have shown their promising potential in high-performance organic field-effect transistors(OFETs). The interfacial dielectric layers are critical in these OFETs as they not only govern the key semiconductor/dielectric interface quality but also determine the growth of OSSCs by their wetting properties. However, reported interfacial dielectric layers either need rigorous preparation processes, rely on certain surface chemistry reactions, or exhibit poor solvent resistance, which limits their applications in low-cost, large-area, monolithic fabrication of OSSC-based OFETs. In this work, polyethylene(PE) thin films and lamellar single crystals are utilized as the interfacial dielectric layers, providing solvent resistive but wettable surfaces that facilitate the crystallization of 6,13-bis(tri-isopropylsilylethynyl)pentacene(TIPS-PEN) and 6,13-bis(triisopropylsilylethynyl)-5,7,12,14-tetraazapentacene(TIPS-TAP). As evidenced by the presence of ambipolar behavior in TIPS-PEN single crystals and the high electron mobility(2.3 ± 0.34 cm^(2)V^(-1)s^(-1)) in TIPS-TAP single crystals, a general improvement on electron transport with PE interfacial dielectric layers is revealed, which likely associates with the chemically inertness of the saturated C-H bonds. With the advantages in both processing and device operation, the PE interfacial dielectric layer potentially offers a monolithic way for the enhancement of electron transport in solution-processed OSSC-based OFETs.

关键词： Polyethylene Interfacial dielectric layer Organic semiconductor Single crystal Organic field-effect transistors