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Friction 2024年第7期12卷 1564-1579页

作者： linlin DUAN Dan jia jian li jianfang liU Haitao DUAN State Key Laboratory of Special Surface Protection Materials and Application Technology Wuhan Research Institute of Materials ProtectionWuhan 430030China Hubei Longzhong Laboratory Xiangyang 441000China College of life Science and Technology Wuhan Polytechnic UniversityWuhan 430030China

In this work,the advantage of Coulomb repulsion in the intermolecular forces experienced by molecules on the solid–liquid nanosized contact interface is taken,and the superior friction-reducing property of Cu_(3)(PO_(4))2·3H_(2)O(CuP)oil-based additives has been confirmed for titanium ***-dimensional(3D)CuP nanoflowers(CuP-Fs)with a strong capillary absorption effect are prepared to achieve the homogeneous mixing of solid CuP and lubricating *** by CuP-Fs additives for titanium alloy,friction coefficient(COF)can be reduced by 73.68%,and wear rate(WR)reduced by 99.69%.It is demonstrated that the extraordinary friction-reducing property is due to the repulsive solid–liquid interface with low viscous shear force originating from Coulomb repulsion between polar water molecules in CuP and non-polar oil ***,any steric hindrance or connection between this repulsive solid–liquid interface will trigger the adhesion and increase the viscous shear force,for example,dispersant,hydrogen bondings,and shaky adsorbed water ***,the lamellar thickness of CuP and the molecular size of lubricant both have a great influence on tribological *** the lubrication mechanism based on interface Coulomb repulsion is proposed that may help broaden the scope of the exploration in low-friction nanomaterial design and new lubricant systems.

关键词： lubrication nanomaterial additive solid-liquid interface wear

Joint alignment and steering to manage interference

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Digital Communications and Networks 2024年第2期10卷 429-438页

作者： Zhao li Xiujuan liang yinghou liu jia liu Zheng Yan School of Cyber Engineering Xidian UniversityXi'an710126China Technol.on Commun.Net.Lab. The 54th Research Inst.of China Elec.Technol.Group Corp.Shijiazhuang050081China School of Computer Science and Technology Xidian UniversityXi'an710126China The Department of Communications and Networking(Comnet) Aalto University02150EspooFinland

In wireless communication networks,mobile users in overlapping areas may experience severe interference,therefore,designing effective Interference Management(IM)methods is crucial to improving network ***,when managing multiple disturbances from the same source,it may not be feasible to use existing IM methods such as Interference Alignment(IA)and Interference Steering(IS)*** is because with IA,the aligned interference becomes indistinguishable at its desired Receiver(Rx)under the cost constraint of Degrees-of-Freedom(DoF),while with IS,more transmit power will be consumed in the direct and repeated application of IS to each *** remedy these deficiencies,Interference Alignment Steering(IAS)is proposed by incorporating IA and IS and exploiting their advantages in *** IAS,the interfering Transmitter(Tx)first aligns one interference incurred by the transmission of one data stream to a one-dimensional subspace orthogonal to the desired transmission at the interfered Rx,and then the remaining interferences are treated as a whole and steered to the same subspace as the aligned ***,two improved versions of IAS,i.e.,IAS with Full Adjustment at the Interfering Tx(IAS-FAIT)and Interference Steering and Alignment(ISA),are *** former considers the influence of IA on the interfering user-pair's *** orthogonality between the desired signals at the interfered Rx can be maintained by adjusting the spatial characteristics of all interferences and the aligned interference components,thus ensuring the Spectral Efficiency(SE)of the interfering communication *** ISA,the power cost for IS at the interfered Tx is minimized,hence improving SE performance of the interfered *** the proposed methods are realized at the interfering and interfered Txs cooperatively,the expenses of IM are shared by both *** in-depth simulation results show that joint use of IA and

关键词： Interference Interference management Interference alignment Interference steering Spectral efficiency

Optimizing near-carbon-free nuclear energy systems:advances in reactor operation digital twin through hybrid machine learning algorithms for parameter identification and state estimation

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Nuclear Science and Techniques 2024年第8期35卷 177-203页

作者： li‑Zhan Hong He‑lin Gong Hong‑Jun Ji jia‑liang Lu Han li Qing li Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610041China

Accurate and efficient online parameter identification and state estimation are crucial for leveraging digital twin simulations to optimize the operation of near-carbon-free nuclear energy *** previous studies,we developed a reactor operation digital twin(RODT).However,non-differentiabilities and discontinuities arise when employing machine learning-based surrogate forward models,challenging traditional gradient-based inverse methods and their *** study investigated deterministic and metaheuristic algorithms and developed hybrid algorithms to address these *** efficient modular RODT software framework that incorporates these methods into its post-evaluation module is presented for comprehensive *** methods were rigorously assessed based on convergence profiles,stability with respect to noise,and computational *** numerical results show that the hybrid KNNLHS algorithm excels in real-time online applications,balancing accuracy and efficiency with a prediction error rate of only 1%and processing times of less than 0.1 ***,algorithms such as FSA,DE,and ADE,although slightly slower(approximately 1 s),demonstrated higher accuracy with a 0.3%relative L_2 error,which advances RODT methodologies to harness machine learning and system modeling for improved reactor monitoring,systematic diagnosis of off-normal events,and lifetime management *** developed modular software and novel optimization methods presented offer pathways to realize the full potential of RODT for transforming energy engineering practices.

关键词： Parameter identification State estimation Reactor operation digital twin Reduced order model Inverse problem

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Study on detecting main ingredients of silicone rubber based on terahertz spectrum

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High Voltage 2024年第3期9卷 518-527页

作者： Hongwei Mei Lanxin li Fanghui yin liming Wang Masoud Farzaneh Shenzhen International Graduate School(SIGS) Tsinghua UniversityShenzhenGuangdongChina Kunming Power Exchange Center KunmingYunnanChina Department of Applied Sciences(DSA) University of Quebec at ChicoutimiChicoutimiQuebecCanada

The authors investigated the ingredient detection technique of silicone rubber based on the Terahertz *** this purpose,18 diverse high-temperature vulcanised silicone rubber(HTVSR)formulations were customised,8 of which are used as calibration set while the rest 10 as prediction *** on the Beer-Lambert Law,the partial-least-square(PLS)regression model and the least-squares support-vector machines(LS-SVM)regression model were used to yield the relationships between the absorption spectrums and the content percentages of polydimethylsiloxane(PDMS),alumina tri-hydrate(ATH),and silica in *** results showed that for the formulations tested,the prediction accuracy of all three main ingredients by the PLS regression model could be improved by changing the spectrum range from 0.2–4 to 0.5–2 *** the data were pre-processed by the Savitzky–Golay smoothing method or multiplicative scatter correction method,the prediction accuracy of PDMS could be further ***,this would lead to a slight decrease in the prediction accuracy of *** the LS-SVM regression model,the radial basis function(RBF)kernel and the linear kernel were *** was found that the prediction accuracy of both kernels was better than that of the PLS regression *** the LS-SVM regression model using the RBF kernel,the correlated coefficients of PDMS and ATH in the prediction set could be up to 0.9915 and 0.9742,respectively.

关键词： rubber spectrum kernel

Preparation and performance improvement of a dual-component microcapsule self-healing system for silicone rubber insulating material

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High Voltage 2024年第2期9卷 453-465页

作者： Mingzhe li Bin Cao Fanghui yin Hongwei Mei liming Wang Engineering Laboratory of Power Equipment Reliability in Complicated Coastal Environments Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhenChina

A key factor limiting the development of silicone rubber insulating materials is their short service life in harsh operating *** establishment of a self-healing system is desired to improve the long-term operational performance of silicone rubber and effectively extend its service *** this study,poly(urea-formaldehyde)microcapsules containing polydimethylsiloxane healing agents are prepared and a dual-component microcapsule self-healing system for silicone rubber material is established and *** addition,the key factors affecting the self-healing performance(such as microcapsule size,rupture rate,and microcapsule doping amount)are *** is found that when SYLGARDTM 184 is used as the healing agent and matrix,with a 4:6(A:B)doping ratio of dual-component microcapsules and 20 phr doping amount,the self-healing efficiency is approximately 51%.Furthermore,increasing the microcapsule rupture rate and the interface strength between the healing agent and the matrix can effectively improve the self-healing *** relationships between key factors and self-healing performance are theoretically *** on the relationships,the microcapsule self-healing system can be appropriately *** results of this paper can provide a reference for the development of long-life silicone rubber insulating materials.

关键词： service rubber performance

Implications of T cell-mediated tumor killing genes for molecular heterogeneity and clinical stratification in lung adenocarcinoma

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Genes & Diseases 2024年第4期11卷 39-41页

作者： Tong Qiao Beining yin Jun liang li Wei Department of Thoracic Surgery Henan Provincial People's HospitalZhengzhouHenan 450000China Reproductive Medicine Center The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan 450052China Department of Breast Surgery Henan Provincial People's HospitalZhengzhouHenan 450000China

Due to the profound heterogeneity exhibited amongst patients with lung adenocarcinoma(LUAD),considerable variances in clinical efficacy emerge.1 For the aims of precision medicine,a clinical instrument to delineate distinct disease phenotypes and anticipate susceptibility to intervention is *** cytotoxicity mediated through T lymphocytes constitutes a pivotal mechanism of anti-tumoral immunity and the foundation for cancer immunotherapy.?Numerous genes regulating the sensitivity of tumor cells to killing mediated by T lymphocytes(GSTKKs)are conducive to satisfying the aforesaid medical necessity.

关键词： clinical mediated adenocarcinoma

SWG: an architecture for sparse weight gradient computation

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Science China(Information Sciences) 2024年第2期67卷 302-321页

作者： Weiwei WU Fengbin TU Xiangyu li Shaojun WEI Shouyi yin School of Integrated Circuits Tsinghua University Department of Electronic and Computer Engineering The Hong Kong University of Science and Technology

On-device training for deep neural networks(DNN) has become a trend due to various user preferences and scenarios. The DNN training process consists of three phases, feedforward(FF), backpropagation(BP), and weight gradient(WG) update. WG takes about one-third of the computation in the whole training process. Current training accelerators usually ignore the special computation property of WG and process it in a way similar to FF/BP. Besides, the extensive data sparsity existing in WG, which brings opportunities to save computation, is not well explored. Nevertheless, exploiting the optimization opportunities would meet three underutilization problems, which are caused by(1) the mismatch between WG data dimensions and hardware parallelism,(2) the full sparsity, i.e., the sparsity of feature map(Fmap),error map(Emap), and gradient, and(3) the workload imbalance resulting from irregular sparsity. In this paper, we propose a specific architecture for sparse weight gradient(SWG) computation. The architecture is designed based on hierarchical unrolling and sparsity-aware(HUSA) dataflow to exploit the optimization opportunities of the special computation property and full data sparsity. In HUSA dataflow, the data dimensions are unrolled hierarchically on the hardware architecture. A valid-data trace(VDT) mechanism is embedded in the dataflow to avoid the underutilization caused by the two-sided input sparsity. The gradient is unrolled in PE to alleviate the underutilization induced by output sparsity while maintaining the data reuse opportunities. Besides, we design an intra-and inter-column balancer(IIBLC) to dynamically tackle the workload imbalance problem resulting from the irregular sparsity. Experimental results show that with HUSA dataflow exploiting the full sparsity, SWG achieves a speedup of 12.23× over state-of-the-art gradient computation architecture, Train Ware. SWG helps to improve the energy efficiency of the state-of-the-art training accelerator LNPU from

关键词： CNN training gradient computation sparsity architecture

Local failure mechanism of sand-blocking fence in latticed dune along desert roads

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Journal of Mountain Science 2024年第2期21卷 526-537页

作者： li liangying LV Lele li Qi WANG Zhenqiang YANG Youhai yin Wenhua School of Civil Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Ningxia Highway Survey and Design Institute Co Ltd Yinchuan 750001China

The latticed dunes in the Tengger Desert are widely distributed,and the sand-blocking fence placed here are highly susceptible to local failure due to complex wind-sand activities,posing a serious threat to the safe operation of the *** explore the local failure mechanism of sand-blocking fence in the latticed dune area,the local failure of sand-blocking fence in the latticed dune areas along the Wuhai-Maqin Highway in China was *** the first main ridge of the latticed dune as the placement location,the structure of the wind-sand flow field of sand-blocking fence placed at top,the bottom and the middle of windward slope was analyzed by Computational Fluid Dynamics(CFD).The results show that when placed at top of the first main ridge,the wind speed near the sand-blocking fence is the highest,up to 15.23 m/***,the wind load strength on the sand barrier is correspondingly larger,up to 232.61 N∙*** the strength of material continues to decrease,the nylon net is prone to *** roots of the angle steel posts are susceptible to hollowing by vortex action,which can cause sand-blocking fence to fall over in strong wind *** placed at the bottom of windward slope,wind speed drop near sand-blocking fence is greatest,with the decrease of 12.48-14.32 m/s compared to the original wind *** is highly likely to lead to large-scale deposition of sand particles and burial of the sand-blocking *** placed in the middle of windward slope,sand-blocking fence is subjected to less wind load strength(168.61N∙m-2)and sand particles are mostly deposited at the bottom of windward slope,with only a small amount of sand accumulating at the root of sand-blocking *** on field observations and numerical modelling results,when the sand-blocking fence is placed in latticed dune area,it should be placed in the middle of the windward slope of the first main ridge as a matter of *** the sand-blocking fence should be placed

关键词： Latticed dune Sand-blocking fence Local failure Numerical simulation Desert roads

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Planning method of droplet fusion scheduling based on mixedinteger programming

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Science China(Technological Sciences) 2024年第1期67卷 157-171页

作者： XIONG jiaCong CHEN jianKui WANG YiXin yin ZhouPing li YiQun State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The emergence of new display devices,such as organic light-emitting diodes,has brought about numerous advantages,including high material utilization,low cost,and high *** devices are manufactured using inkjet printing and possess the potential to become a key technology for display ***,a challenge in achieving this is the display effect that reveals uneven brightness and darkness,which can be avoided by controlling the volume of ink solution in a pixel to within 5%.Currently,the volume difference among the nozzles of commercial printheads does not meet the requirements for volume uniformity,thus challenging the printing ***,designing a suitable printing method that allows for the fusion of different volumes of ink droplets,ultimately reducing the error of the post fusion process,is *** this study,we propose a print display droplet fusion scheduling method comprising two main ***,we use a dichotomous trust domain algorithm to obtain a feasible range of printhead docking point spacings for different nozzle and pixel panel ***,we model the printing process as a droplet fusion scheduling model based on mixed integer programming,with the optimization objective of achieving intra pixel volume uniformity via ensuring the volume uniformity of ink droplets within all *** verified this method through numerical simulations and printing experiments using 394 pixels per inch(ppi)pixel panels and successfully reduced the volume uniformity error among pixels to within 5%.

关键词： printing display droplet fusion mixed-integer programming dichotomous trust domain

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Trade-off analyses between food provision and soil conservation service of Grain for Green Program in Mountainous Area

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International Soil and Water Conservation Research 2024年第1期12卷 43-53页

作者： Yawen li Yuxiang li Xingwu Duan Zhongyin Cai Ya li Baiyun He Long yin Institute of International River and Eco-security Yunnan UniversityKunming650091PR China Yunnan Key Laboratory of International Rivers and Trans-boundary Eco-security Kunming650091PR China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085PR China University of Chinese Academy of Sciences Beijing100049PR China

The Grain for Green Program and soil and water conservation engineering initiatives are crucial for controlling erosion in steep-slope ***,it is still unclear how these two management methods should be carried out in respect to the situation in mountainous ***,taking a typical mountainous area in southwest China as an example,we simulated six scenarios in order to compare the food provisioning service(FPS)and soil conservation service of the Grain for Green Program(converting to grassland)and Construction Measures(converting to sloping terrace)under different *** showed that when farmland with a>25°slope was converted into grassland,the amount of soil erosion(M)decreased by 21.0%,while FPS decreased by only 0.7%.However,when farmland with a>25°slope was converted into sloping terrace,M decreased by 31.3%while FPS increased by 18.7%.With the increases of farmland slope ranges in the Construction Measures scenario,M gradually decreased and FPS gradually *** when farmland>15°was converted into sloping terrace,M decreased by 63.9%and FPS increased by 52.7%.Furthermore,the trade-offs of Construction Measures are lower than that of Grain for Green on different slope ***,we conclude that Construction Measures are a more suitable method in mountainous areas than the Grain for Green,and we suggest that further research be conducted to consider the ecological risks of construction engineering measures.

关键词： Soil erosion Grain for green Construction measures Mountainous areas