检索结果-南通市图书馆

Efficient OpenMP Based Z-curve Encoding and Decoding Algorithms

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2025年第1期82卷 1313-1327页

作者： Zicheng Zhou Shaowen Sun Teng Liang Mengjuan Li Fengling Xia School of Electronic Science and engineering University of Electronic Science and Technology of ChinaChengdu611731China faculty of Information engineering and Automation Kunming University of Science and TechnologyKunming650500China School of Communications Information engineering Yunnan Communications Vocational and Technical CollegeKunming650500China Library Yunnan Normal UniversityKunming650500China faculty of civil Aviation and Aeronautics Kunming University of Science and TechnologyKunming650500China

Z-curve’s encoding and decoding algorithms are primely important in many Z-curve-based *** bit interleaving algorithm is the current state-of-the-art algorithm for encoding and decoding *** simple,its efficiency is hindered by the step-by-step coordinate shifting and bitwise *** tackle this problem,we first propose the efficient encoding algorithm LTFe and the corresponding decoding algorithm LTFd,which adopt two optimization methods to boost the algorithm’s efficiency:1)we design efficient lookup tables(LT)that convert encoding and decoding operations into table-lookup operations;2)we design a bit detection mechanism that skips partial order of a coordinate or a Z-value with consecutive 0s in the front,avoiding unnecessary iterative *** propose order-parallel and point-parallel OpenMP-based algorithms to exploit the modern multi-core *** results on discrete,skewed,and real datasets indicate that our point-parallel algorithms can be up to 12.6×faster than the existing algorithms.

关键词： Z-curve lookup table OpenMP bit detection mechanism

A complementary approach to quantify the basic GSI chart considering scale effect on rock structure

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical engineering 2025年第1期17卷 154-167页

作者： Harun Sonmez Gulseren Dagdelenler Yilmaz Ozcelik Murat Ercanoglu Applied Geology Division Geological Engineering DepartmentFaculty of EngineeringHacettepe UniversityBeytepeAnkara06800Türkiye Mining engineering Department Faculty of EngineeringHacettepe UniversityBeytepeAnkara06800Türkiye

Geological strength index(GSI)has been widely used as an input parameter in predicting the strength and deformation properties of rock *** study derived a series of equations to satisfy the original GSI lines on the basic GSI *** axes ranging from 0 to 100 were employed for surface conditions of the discontinuities and the structure of rock mass,which are independent of the input *** derived equations can analyze GSI values ranging from 0 to 100 within±5%*** engineering dimensions(EDs)such as the slope height,tunnel width,and foundation width were used together with representative elementary volume(REV)in jointed rock mass to define scale factor(sf)from 0.2 to 1 in evaluating the rock mass structure including joint *** transformation of GSI into a scaledependent parameter based on engineering scale addresses a crucial requirement in various engineering *** improvements proposed in this study were applied to a real slope which was close to the time of *** results of stability assessments show that the new proposals have sufficient capability to define rock mass quality considering EDs.

关键词： Basic GSI chart engineering dimension(ED) Hoek and Brown failure criterion Quantification of GSI Quantitative GSI chart Scale effect

Upper bound stability analysis of tiered geosynthetic-reinforced soil wall

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical engineering 2025年第1期17卷 556-572页

作者： Chengzhi Xiao Xiangsheng Meng Shan Gao Luqiang Ding School of civil and Transportation engineering Hebei University of TechnologyTianjin300401China

The tiered geosynthetic-reinforced soil (GRS) walls have been increasingly applied in the high and steep retaining soil structures. However, very little is known about the design method for the tiered GRS wall in practice. This study is aimed at proposing an upper-bound stability analysis method of a tiered GRS wall. The proposed method was firstly validated by the existing results from the centrifuge test and the numerical method, and then a parametric study was performed to investigate the effects of the cohesionless backfill friction angle φ1 and the wall geometric parameters including the offset distance, the total wall height, the batter angle δ, the number of tiers n, and wall height ratio of adjacent tiers on the dimensionless equivalent earth pressure coefficient KT. The analysis results demonstrated that as the φ1 increases, the shear strength of backfill is enhanced and thus the KT or the total reinforcement tensile force decreases, and the KT decreases with the increase of the offset distance at the initial stage and then becomes stable when it reaches a certain critical value. For a fixed offset distance, the KT or the total reinforcement tensile force decreases with the increase of the δ. For the two-tiered GRS walls having the offset distance less than the critical value, the wall with the smaller wall height ratio has a larger KT. Further, the variation of the location of the critical failure surfaces of tiered GRS walls was presented in this study with the variation of the φ1 and the wall geometry.

关键词： Geosynthetics Tiered GRS walls Offset distance Upper bound theorem Internal stability

Rainfall-induced wind erosion in soils stabilized with alkali-activated waste materials

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical engineering 2025年第1期17卷 465-480页

作者： Alireza Komaei Abbas Soroush Seyed Mohammad Fattahi Hesam Ghanbari Department of civil and Environmental engineering Amirkabir University of TechnologyTehran159163431Iran

This study evaluates the efficacy of sustainable erosion control using slag-based alkali-activated cement crusts under varying rainfall and wind conditions. The rainfall intensities ranged from 30 mm/h to 120 mm/h, with durations ranging from 15 min to 90 min, and crust slopes of ∼2° (gentle) and 30° (steep). Wind tunnel experiments were conducted at wind velocities of 14 m/s, 21 m/s, and 28 m/s to investigate post-rainfall wind erodibility, along with changes in crust strength and microstructure analysis. The findings show the development of hydrated cementitious phases in alkali-activated material, which form around and between the particles during the alkaline activation process. Alkali-activated cement crusts significantly reduced erosion caused by rainfall and subsequent wind by several orders of magnitude. At the highest rainfall intensity of 120 mm/h, rainfall erosion was measured to be 1654.81 kg/m2 for untreated samples and 0.89 kg/m2 for treated samples, demonstrating a substantial 99.95% reduction in erosion due to the treatment. Similarly, at the highest wind speed tested, wind erosion was 122.75 kg/m2 for untreated samples and 0.095 kg/m2 for treated samples, indicating a significant 99.92% reduction in erosion due to the formation of an alkali-activated cement crust on the soil surface. However, exposure of the samples to 120 mm/h rainfall for 90 min resulted in a 5.2-fold increase in wind erosion compared to pre-rainfall conditions. Similarly, penetrometer results indicated a 37%–54% reduction in post-rainfall surface strength.

关键词： Rainfall erosion Alkali-activated material Wind erosion Crust formation

Pushing the Boundaries of Starch Foams: Novel Laminar Composites with Paper Reinforcement

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Renewable Materials 2025年第1期13卷 101-114页

作者： Manisara Phiriyawirut Pukrapee Rodprasert Peerapat Kulvorakulpitak Ratiwan Cothsila Nattarat Kengkla Department of Tool and Materials engineering Faculty of EngineeringKing Mongkut’s University of Technology ThonburiBangkok10140Thailand

This work explores the development of biodegradable laminar composite foams for cushioning *** focus lies on overcoming the inherent brittleness of starch foams by incorporating various paper types as *** starch and glutinous starch were blended in varying ratios(100:0–0:100)to optimize the base material’s *** morphology,density,ﬂexural strength,and impact strength of these starch blends were *** results revealed a trade-off between impact strength and density,with increasing glutinous starch content favoring impact resistance but also leading to higher *** optimal ratio of tapioca to glutinous starch for achieving maximumﬂexural strength and modulus was determined to be 60:***ﬂexural strength of the composite material at this ratio reached a peak value of 5.3±0.6 MPa,signiﬁcantly surpassing theﬂexural strength of pure tapioca foam,which was measured to be 3.5±0.4 *** on this foundation,novel lami-nar composite foams were fabricated using the 60:40 starch blend reinforced with mulberry paper,kraft paper,and newsprint *** enhance the interfacial adhesion between the starch matrix and paper reinforcement,a silane coupling agent was employed at a 10 wt%loading on the *** incorporation of paper reinforcement into starch foams was found to enhance their mechanical ***ﬁcally,ﬂexural strength values increased from 5.3±0.6 MPa for the unreinforced starch foam to 6.8±0.6 MPa,8.1±0.9 MPa,and 7.4±0.1 MPa when reinforced with mulberry paper,kraft paper,and newsprint paper,***,kraft paper reinforcement led to the most enhancements inﬂexural strength,ﬂexural modulus,and impact *** research paves the way for developing sustainable cushioning materials with competitive mechanical properties using bio-based resources like starch and paper.

关键词： Laminar composite starch foam tapioca starch glutinous starch kraft paper

Nanosecond pulse and dual-wavelength Q-switched 1.5 μm fiber laser using MAX phase Cr_(2)TiAlC_(2) saturable absorber

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Optoelectronics Letters 2025年第1期21卷 7-12页

作者： Ahmed Shakir AL-HITI Hiba HASSAN Department of Electrical engineering Faculty of EngineeringUniversity of AnbarAnbar 31001Iraq Department of Laser and Optoelectronics engineering University of Technology-IraqBaghdadIraq

We demonstrated a new type of MAX phase material,chromium titanium aluminum carbide(Cr_(2)TiAlC_(2)) polymer film,to generate a passively Q-switched erbium-doped fiber laser(EDFL).The film thickness was measured to be around 45 μm,which was fabricated using the embedding method with polyvinyl alcohol(PVA) polymer as *** saturable absorber(SA) film demonstrates a dual-wavelength passively Q-switched EDFL which operates at 1 531 nm and 1 560.19 nm,*** Q-switching pulse duration could be varied from 2.46 μs to 770 ns,while the repetition rate varied from 92.76 kHz to 106.6 kHz with an increasing input pumping range from 154 mW to 300 *** maximum output power and pulse energy of 15.05 mW and 141.18 nJ were obtained at the maximum input power of 300 mW,respectively.

关键词： switched pulse fiber

维普期刊数据库

Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： Xinguang Zhu Chenxi Ding Zhe Sui Hong Su Xu Guo School of civil and Resources engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanics and civil engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Chemical and Blasting engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

维普期刊数据库

Micro-macro regulating heterogeneous interface engineering in 3D N-doped carbon fiber/MXene/TiO_(2) nano-aerogel for boosting electromagnetic wave absorption

在线全文

学校读者我要写书评

暂无评论

Nano Research 2025年第2期18卷 843-857页

作者： Ying Li Chunlei Dong Sijia Wang Dongyi Lei Binbin Yin Yifei Cui Yanru Wang Ran Li School of civil engineering Qingdao University of TechnologyQingdao 266033China Cooperative Innovation Center of engineering Construction and Safety in Shandong Blue Economic Zone Qingdao University of TechnologyQingdao 266033China Department of Architecture and civil engineering City University of Hong KongHong Kong 999077China

MXene,as a rising star among two-dimensional(2D)electromagnetic wave materials,faces urgent challenges in addressing its self-stacking issue and regulating its ***,a micro-macro collaborative design strategy was proposed to regulate heterogeneous interface engineering in MXene-based ***-based cotton was introduced as three dimensional(3D)framework for constructing a porous structure,TiO_(2) was in-situ generated and nitrogen atom was doped on Ti_(3)C_(2)T_(x) MXene to regulate its dielectric properties,a 3D N-doped carbon fiber/MXene/TiO_(2)(CMT)nano-aerogel was successful *** synergistic effects of diverse components and structural designs,porous frameworks and TiO_(2) lattice contraction can significantly adjust the density of the conductive network and create abundant heterogeneous interfaces,as well as the lattice defects induced by nitrogen atom doping can enhance polarization loss,ultimately leading to the excellent microwave absorption performance of 3D N-CMT *** optimized N-CMT 30%aerogel exhibited a minimum reflection loss(RLmin)of−72.56 dB and an effective absorption bandwidth(EAB)of 6.92 GHz at 2.23 ***,when the thickness was adjusted from 1 to 5 mm,the EAB of the N-CMT 30%aerogel reached 13.94 GHz,achieving coverage of 98% of the C-band and the entire X and Ku ***,the attenuation capabilities of the N-CMT aerogel were further confirmed through RCS simulations,whose RCS reduction value reaches up to 19.969 dB·m^(2).These results demonstrate that 3D N-CMT nano-aerogel relying on interface engineering design exhibits significant potential in the field of electromagnetic protection,providing an important reference for future efficient absorbers.

关键词： interface engineering electromagnetic wave absorption MXene micro-macro design nano-aerogel

Mini review:Strategies for enhancing stability of high-voltage cathode materials in aqueous zinc-ion batteries

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2025年第1期36卷 214-224页

作者： Lingjiang Kou Yong Wang Jiajia Song Taotao Ai Wenhu Li Mohammad Yeganeh Ghotbi Panya Wattanapaphawong Koji Kajiyoshi School of Materials Science and engineering Shaanxi University of TechnologyHanzhong 723000China Research Laboratory of Hydrothermal Chemistry Faculty of Science and TechnologyKochi UniversityKochi 780-8081Japan Institute of Power engineering(IPE) Universiti Tenaga NasionalKajangSelangor 43000Malaysia Materials engineering Department Faculty of EngineeringMalayer UniversityMalayerIran

As battery technology evolves and demand for efficient energy storage solutions,aqueous zinc ion batteries(AZIBs)have garnered significant attention due to their safety and environmental ***,the stability of cathode materials under high-voltage conditions remains a critical challenge in improving its energy *** review systematically explores the failure mechanisms of high-voltage cathode materials in AZIBs,including hydrogen evolution reaction,phase transformation and dissolution *** address these challenges,we propose a range of advanced strategies aimed at improving the stability of cathode *** strategies include surface coating and doping techniques designed to fortify the surface properties and structure integrity of the cathode materials under high-voltage ***,we emphasize the importance of designing antioxidant electrolytes,with a focus on understanding and optimizing electrolyte decomposition *** review also highlights the significance of modifying conductive agents and employing innovative separators to further enhance the stability of *** integrating these cutting-edge approaches,this review anticipates substantial advancements in the stability of high-voltage cathode materials,paving the way for the broader application and development of AZIBs in energy storage.

关键词： Aqueous zinc ion battery High-voltage cathode materials Stability enhancement Failure mechanisms Electrolyte optimization

维普期刊数据库