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Additive manufacturing of micropatterned functional surfaces:a review

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International journal of Extreme Manufacturing 2024年第4期6卷 86-114页

作者： Aditya Chivate Chi zhou Department of Industrial and Systems Engineering University at BuffaloThe State University of New YorkBuffaloNY 14260United States of America

Over the course of millions of years,nature has evolved to ensure survival and presents us with a myriad of functional surfaces and structures that can boast high efficiency,multifunctionality,and *** makes these surfaces particularly practical and effective is the intricate micropatterning that enables selective interactions with *** of these structures have been realized in the laboratory environment using numerous fabrication techniques by tailoring specific surface *** the available manufacturing methods,additive manufacturing(AM)has created opportunities for fabricating these structures as the complex architectures of the naturally occurring microstructures far exceed the traditional *** paper presents a concise overview of the fundamentals of such patterned microstructured surfaces,their fabrication techniques,and diverse applications.A comprehensive evaluation of micro fabrication methods is conducted,delving into their respective strengths and *** emphasis is placed on AM processes like inkjet printing and micro digital light projection printing due to the intrinsic advantages of these processes to additively fabricate high resolution structures with high fidelity and *** paper explores the various advancements in these processes in relation to their use in microfabrication and also presents the recent trends in applications like the fabrication of microlens arrays,microneedles,and tissue scaffolds.

关键词： additive manufacturing micropatterned surfaces drop-on-demand inkjet DLP printing

Origin and tectonic setting of low-Si alkaline magma

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Science China Earth Sciences 2024年第5期67卷 1417-1435页

作者： Qiushi zhou Rui WAng State Key Laboratory of Geological Processes and Mineral Resources and Institute of Earth SciencesChina University of GeosciencesBeijing 100083China Frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing 100083China

Despite of the relatively rare occurrence of alkaline igneous rocks on Earth, they are the most diverse group of igneous rocks due to variations in their mineral assemblages and geochemical compositions. Alkaline igneous rocks are generally characterized by Si undersaturation, and K-Na(and in some cases C) enrichment. Although there is no unified alkaline igneous rock classification scheme, diagrams such as total alkalis-SiO_(2) or K_(2)O-SiO_(2) can be used to classify alkaline igneous rocks. The origins of silica-saturated alkaline rocks(SiO_(2)>52 wt.%) are relatively complex because multiple episodes of magmatism are often involved, therefore most studies have focused on the origins of silica-undersaturated alkaline *** experimental petrological studies have been conducted in the past few decades. Initially, it was considered that enrichment of trace elements was only achieved by low-degree partial melting of mantle peridotite, but the experimental melts could not reproduce the geochemical composition of natural alkaline igneous rocks. Subsequent studies have focused on carbonate-bearing eclogites that represent the average component of subducted oceanic crust. Although experimental studies indicate that silica-undersaturated and alkali-oversaturated melts can be generated from eclogites, some studies have considered that natural silica-undersaturated alkaline igneous rocks are the result of multi-stage source enrichment by incompatible elements. Low-degree partial melts of the mantle can be emplaced in the lithospheric mantle, forming veins consisting of phlogopite, amphibole, and pyroxene. Melting experiments including these components show that the produced melts better reproduce the naturally occurring silica-undersaturated alkaline magmas. Silica-deficient alkaline igneous rocks occur in various tectonic settings. Those in intraplate and divergent settings(i.e., mainly continental rifts) normally involve contributions from recycled components su

关键词： Alkaline igneous rock Tectonic setting Petrogenesis Big data

Precise genome-editing in human diseases:mechanisms,strategies and applications

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Signal Transduction and Targeted Therapy 2024年第3期9卷 1065-1085页

作者： yanjiang Zheng Yifei Li Kaiyu zhou Tiange Li Nathan j.VanDusen Yimin Hua Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE Department of PediatricsWest China Second University HospitalSichuan UniversityChengduSichuan 610041China Department of Cardiovascular Surgery West China HospitalSichuan UniversityChengduSichuan 610041China Department of Pediatrics Herman B Wells Center for Pediatric ResearchIndiana University School of MedicineIndianapolisIN 46202USA

Precise genome-editing platforms are versatile tools for generating specific,site-directed DNA insertions,deletions,and *** continuous enhancement of these tools has led to a revolution in the life sciences,which promises to deliver novel therapies for genetic *** genome-editing can be traced back to the 1950s with the discovery of DNA’s doublehelix and,after 70 years of development,has evolved from crude in vitro applications to a wide range of sophisticated capabilities,including in vivo ***,precise genome-editing faces constraints such as modest efficiency,delivery challenges,and off-target *** this review,we explore precise genome-editing,with a focus on introduction of the landmark events in its history,various platforms,delivery systems,and ***,we discuss the landmark events in the history of precise ***,we describe the current state of precise genome-editing strategies and explain how these techniques offer unprecedented precision and versatility for modifying the human ***,we introduce the current delivery systems used to deploy precise genome-editing components through DNA,RNA,and ***,we summarize the current applications of precise genome-editing in labeling endogenous genes,screening genetic variants,molecular recording,generating disease models,and gene therapy,including ex vivo therapy and in vivo therapy,and discuss potential future advances.

关键词： precise generating editing

Revealing the Void Formation Mechanism during Superplastic Deformation of a Fine-Grained Ni-Co-Base Superalloy

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 915-920页

作者： Rashad AAl-Hammadi Rui Zhang Chuanyong Cui Zijian zhou Yizhou zhou Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

The mechanism behind void formation during superplasticity remains a subject of *** study presented a novel insight into the void formation in a fine-grained Ni-Co-based superalloy during *** was observed that the dissolution ofγ′-particles resulted in the creation of vacancies due to differences in atomic size between the matrix and the *** vacancies acted as inclusions,leading to the formation of ***,excessive void formation correlated with higher particle dissolution was experimentally observed,highlighting a direct relationship between void formation and particle dissolution.

关键词： Superplasticity Void formation Ni-Co-based superalloy Microstructure

Adaptive state-constrained/model-free iterative sliding mode control for aerial robot trajectory tracking

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 603-618页

作者： Chen AN jiaxi zhou Kai WAng College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina

This paper develops a novel hierarchical control strategy for improving the trajectory tracking capability of aerial robots under parameter *** hierarchical control strategy is composed of an adaptive sliding mode controller and a model-free iterative sliding mode controller(MFISMC).A position controller is designed based on adaptive sliding mode control(SMC)to safely drive the aerial robot and ensure fast state convergence under external ***,the MFISMC acts as an attitude controller to estimate the unmodeled dynamics without detailed knowledge of aerial ***,the adaption laws are derived with the Lyapunov theory to guarantee the asymptotic tracking of the system ***,to demonstrate the performance and robustness of the proposed control strategy,numerical simulations are carried out,which are also compared with other conventional strategies,such as proportional-integralderivative(PID),backstepping(BS),and *** simulation results indicate that the proposed hierarchical control strategy can fulfill zero steady-state error and achieve faster convergence compared with conventional strategies.

关键词： aerial robot hierarchical control strategy model-free iterative sliding mode controller(MFISMC) trajectory tracking reinforcement learning

Consecutive narrow and broad quasi-periodic fast-propagating wave trains associated with a flare

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 200-211页

作者： Xinping zhou Yuandeng Shen Chengrui zhou Zehao Tang Ahmed Ahmed Ibrahim College of Physics and Electronic Engineering Sichuan Normal UniversityChengdu 610068China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Department of Physics and Astronomy College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia

The excitation mechanism of coronal quasi-period fast-propagating(QFP)wave trains remains *** Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory observations,we study a narrow and a broad QFP wave trains excited one after another during the successive eruptions of filaments hosted within a fan-spine magnetic system on October 20,*** consecutive occurrence of these two types of QFP wave trains in the same event provides an excellent opportunity to explore their excitation mechanisms and compare their physical *** observational results reveal that narrow and broad QFP wave trains exhibit distinct speeds,periods,energy fluxes,and relative intensity amplitudes,although originating from the same active region and being associated with the same GOES C2.9 *** wavelet analysis,we find that the narrow QFP wave train shares a similar period with the flare itself,suggesting its possible excitation through the pulsed energy release in the magnetic reconnection process that generated the accompanying *** the other hand,the broad QFP wave train appears to be associated with the energy pulses released by the successive expansion and unwinding of filament ***,it is plausible that the broad QFP wave train was also excited by the sequential stretching of closed magnetic field lines driven by the erupting *** findings shed light on the different excitation mechanisms and origins of the QFP wave trains.

关键词： narrow wave excitation

Efficient Penetration Testing Path Planning Based on Reinforcement Learning with Episodic Memory

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2613-2634页

作者： Ziqiao zhou Tianyang zhou j.nghao Xu junhu Zhu Henan Key Laboratory of Information Security National Engineering Technology Research Center of the Digital Switching SystemZhengzhou450000China School of Cryptographic Engineering Information Engineering UniversityZhengzhou450000China

Intelligent penetration testing is of great significance for the improvement of the security of information systems,and the critical issue is the planning of penetration test *** view of the difficulty for attackers to obtain complete network information in realistic network scenarios,Reinforcement Learning(RL)is a promising solution to discover the optimal penetration path under incomplete information about the target *** RL-based methods are challenged by the sizeable discrete action space,which leads to difficulties in the ***,most methods still rely on experts’*** address these issues,this paper proposes a penetration path planning method based on reinforcement learning with episodic ***,the penetration testing problem is formally described in terms of reinforcement *** speed up the training process without specific prior knowledge,the proposed algorithm introduces episodic memory to store experienced advantageous strategies for the first ***,the method offers an exploration strategy based on episodic memory to guide the agents in *** design makes full use of historical experience to achieve the purpose of reducing blind exploration and improving planning ***,comparison experiments are carried out with the existing RL-based *** results reveal that the proposed method has better convergence *** running time is reduced by more than 20%.

关键词： Intelligent penetration testing penetration testing path planning reinforcement learning episodic memory exploration strategy

Predicting the International Roughness Index of jPCP and CRCP Rigid Pavement:A Random Forest(RF)Model Hybridized with Modified Beetle Antennae Search(MBAS)for Higher Accuracy

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1557-1582页

作者： zhou ji Mengmeng zhou Qiang Wang jiandong Huang College of Civil and Environmental Engineering Hunan University of Science and EngineeringYongzhou425006China School of Mines China University of Mining and TechnologyXuzhou221116China School of Civil Engineering Guangzhou UniversityGuangzhou510006China

To improve the prediction accuracy of the International Roughness Index(IRI)of jointed PlainConcrete Pavements(jPCP)and Continuously Reinforced Concrete Pavements(CRCP),a machine learning approach is developed in this study for the modelling,combining an improved Beetle Antennae Search(MBAS)algorithm and Random Forest(RF)*** 10-fold cross-validation was applied to verify the reliability and accuracy of the model proposed in this *** importance scores of all input variables on the IRI of jPCP and CRCP were analysed as *** results by the comparative analysis showed the prediction accuracy of the IRI of the newly developed MBAS and RF hybrid machine learning model(RF-MBAS)in this study is higher,indicated by the RMSE and R values of 0.2732 and 0.9476 for the jPCP as well as the RMSE and R values of 0.1863 and 0.9182 for the *** accuracy of this obtained result far exceeds that of the IRI prediction model used in the traditional Mechanistic-Empirical Pavement Design Guide(MEPDG),indicating the great potential of this developed *** importance analysis showed that the IRI of jPCP and CRCP was proportional to the corresponding input variables in this study,including the total joint faulting cumulated per KM(TFAULT),percent subgrade material passing the 0.075-mm Sieve(P_(200))and pavement surface area with flexible and rigid patching(all Severities)(PATCH)which scored higher.

关键词： Cement pavement jPCP CRCP RF-MBAS IRI

Spatial Distribution Feature Extraction Network for Open Set Recognition of Electromagnetic Signal

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 279-296页

作者： Hui Zhang Huaji zhou Li Wang Feng zhou The Ministry Key Laboratory of Electronic Information Countermeasure and Simulation Xidian UniversityXi’an710071China Science and Technology on Communication Information Security Control Laboratory Jiaxing314033China

This paper proposes a novel open set recognition method,the Spatial Distribution Feature Extraction Network(SDFEN),to address the problem of electromagnetic signal recognition in an open *** spatial distribution feature extraction layer in SDFEN replaces convolutional output neural networks with the spatial distribution features that focus more on inter-sample information by incorporating class center *** designed hybrid loss function considers both intra-class distance and inter-class distance,thereby enhancing the similarity among samples of the same class and increasing the dissimilarity between samples of different classes during ***,this method allows unknown classes to occupy a larger space in the feature *** reduces the possibility of overlap with known class samples and makes the boundaries between known and unknown samples more ***,the feature comparator threshold can be used to reject unknown *** signal open set recognition,seven methods,including the proposed method,are applied to two kinds of electromagnetic signal data:modulation signal and real-world *** experimental results demonstrate that the proposed method outperforms the other six methods overall in a simulated open ***,compared to the state-of-the-art Openmax method,the novel method achieves up to 8.87%and 5.25%higher micro-F-measures,respectively.

关键词： Electromagnetic signal recognition deep learning feature extraction open set recognition