检索结果-内蒙古大学图书馆

A novel hybrid contact detection algorithm for 2D FDEM: Balancing efficiency and memory consumption

engineering Analysis with Boundary Elements 2025年 178卷

作者： Liu, He Zhu, Panpan Liu, Quansheng Tian, Yongchao Lei, Yiming Yin, Xin Shao, Zuliang He, Guicheng Key Laboratory of Safety for Geotechnical and Structural Engineering of Hubei Province School of Civil Engineering Wuhan University Hubei Wuhan430072 China School of Resources Environment and Safety Engineering University of South China Hengyang421001 China School of Civil Engineering Henan Polytechnic University Henan Jiaozuo454003 China Department of Architecture and Civil Engineering City University of Hong Kong Tat Chee Avenue Hong Kong Kowloon China

In this paper, a novel hybrid contact detection algorithm, AGS (Adaptive grid-based search) & GJK (Gilbert-Johnson-Keerthi), is proposed to accelerate 2D FDEM (Combined finite-discrete element method) simulations. AGS algorithm maintains computational efficiency comparable to traditional broad search methods based on uniform grid decomposition, while significantly reducing memory consumption by utilizing only effective grid cells in identifying potential contact pairs. Additionally, a modified GJK algorithm with specific initial search direction is employed for contact resolution, which is not only easy to implement but also more efficient than SAT (Separation Axis Theorem). Compared·to existing FDEM algorithms like NBS (Non-binary Search) and GGS (Global Grid-based Search) & SAT (Separation Axis Theorem), the proposed algorithm effectively overcomes their limitations, offering high computational efficiency, low memory consumption, and reduced sensitivity to mesh size. The effectiveness of the proposed algorithm is validated through multiple numerical cases, demonstrating its suitability for both quasi-static and dynamic simulations. Notably, in the numerical cases examined, the algorithm achieves a speed-up ratio of 2.76 at case scale compared to NBS, and saves 37.8 % in memory consumption compared to GGS & SAT. Furthermore, the algorithm is highly versatile and can potentially be extended to DEM (Discrete Element Method) applications involving other convex-shaped particles. © 2025 Elsevier Ltd

关键词： Discrete element methods

来源：评论

学校读者我要写书评

暂无评论

Digital twin driven thermal error control of linear axis for face gear grinding machine tool

引用

Procedia CIRP 2025年 133卷 436-441页

作者： Mingming Li Chi Ma Jialan Liu Giovanni Totis Academy of Aerospace Solid Propulsion Technology Xi’an 710025 China College of Mechanical and Vehicle Engineering Chongqing University Chongqing 400044 China State Key Laboratory of Mechanical Transmission for Advanced Equipment Chongqing University Chongqing 400044 China School of Construction Machinery Chang’an University Xi’an 710064 China Polytechnic Department of Engineering and Architecture University of Udine Via delle Scienze 206 33100 Udine Italy

The face gear transmission system offers advantages such as high interchangeability, strong load capacity, and effective power distribution, making it suitable for defense applications. The machining accuracy of the face gear grinding machine tool is significantly affected by the geometric and thermal errors, leading to a reduced geometric precision of the machined face gear. The real-time performance and robustness of the geometric and thermal error compensation system are the key to realize the thermal error control. So far, the real-time performance of compensation system is weak, and the robustness is poor. To address the above challenges, the effect of the temperature changes on positioning accuracy is studied. Then the thermal error prediction model is established based on the error mechanism for the linear axis of face gear grinding machine tool. Finally, the digital twin-driven thermal error control system is developed. The thermal error model is embedded into the digital twin-driven geometric and thermal error control system to realize the thermal error compensation of linear axis for face gear grinding machine tool. With the implementation of the digital twin-driven thermal error control system, the left tooth surface error decreased from 21.8 μm to 5.9 μm, and the right tooth surface error decreased from 22.9 μm to 5.7 μm, confirming the effectiveness of the proposed method.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Evaluation of the spatiotemporal changes in ecological quality and public health status: a case study of Jharkhand State in India

引用

Environment, Development and Sustainability 2025年 1-37页

作者： Mohammad, Lal Bandyopadhyay, Jatisankar Mondal, Ismail Altuwaijri, Hamad Ahmed Pradhan, Sumana Hossain, S. K. Ariful Juliev, Mukhiddin Centre for Environmental Studies Vidyasagar University West Bengal Midnapore 721102 India Department of Remote Sensing & GIS Vidyasagar University West Bengal Midnapore 721102 India Department of Marine Science University of Calcutta Kolkata 700019 India Department of Geography College of Humanities and Social Sciences King Saud University Riyadh 1145 Saudi Arabia CSIR National Institute of Oceanography Dona Paula Goa 403 004 India School of Oceanographic Studies Jadavpur University Kolkata 700032 India Institute of Fundamental and Applied Research “TIIAME” National Research University Kori Niyoziy 39 Tashkent 100000 Uzbekistan Department of Scientific Research Kokand University Andijan Branch Jasorat 43 Andijan 170619 Uzbekistan Department of Civil Engineering and Architecture Turin Polytechnic University in Tashkent Little Ring Road Street 17 Tashkent 100095 Uzbekistan

Since the advent of industrialization, air pollution has significantly increased and is now a serious concern to public health issues. Using environmental datasets from remote sensing and ground stations, acute respiratory infection (ARI) records from the Annual Health Survey, and Aerosol Optical Depth (AOD) from MODIS data, this study examines the spatiotemporal variations in air pollution and its health impacts in Jharkhand, India. The findings show notable regional differences, with northern and eastern Jharkhand having greater aerosol concentrations than the southwest. Between 2000 and 2017, Gumla had the lowest mean AOD (0.227 ± 0.02) while Godda district had the highest (0.482 ± 0.05). The variations in AOD revealed the aerosols leading were 33.61% lower during Pre-monsoon than post-monsoon on a seasonal basis. Analysis of health data showed changing patterns in ARI: urban regions saw greater instances by 24.46% (2011–12) and 23.07% (2012–13), whereas rural populations were 41.46% more impacted in 2010–11. The burden of ARI was 4.1% higher in females than in males. Assessments of environmental sensitivity revealed proportionate relationships between aerosol concentration and both atmospheric temperature (AT) and land surface temperature (LST) in the study area. This study emphasizes how useful geospatial methods are for sustainable management and environmental monitoring. The results give policymakers practical advice on how to match mitigation plans with the Sustainable Development Goals (SDGs), guaranteeing focused actions for Jharkhand's public health and air quality improvement. © The Author(s), under exclusive licence to Springer Nature B.V. 2025.

关键词： Acute respiratory infection Aerosols Air pollution Air temperature Environmental impact assessment Health impact assessment Land surface temperature MODIS Remote sensing

来源：评论

学校读者我要写书评

暂无评论

The impact of indoor environmental quality on tourist accommodation ratings using guest reviews

引用

Building and Environment 2025年 280卷

作者： Zhang, Fan Seshadri, Karthick Liu, Shichao Santamouris, Matthaios School of Engineering and Built Environment Griffith University SouthportQLD Australia Department of Computer Science and Engineering National Institute of Technology Andhra Pradesh Tadepalligudem India Department of Civil Environmental Architectural Engineering Worcester Polytechnic Institute MA United States High Performance Architecture School of Built Environment University of New South Wales SydneyNSW Australia

Guest satisfaction is pivotal for the hospitality industry, yet the role of Indoor Environmental Quality (IEQ) in shaping guest ratings remains inadequately explored. This study addresses this gap by leveraging web-mining, natural language processing and the Three-Factor Theory to analyse guest reviews of Australian hotels and serviced apartments listed on ***. Findings indicate that most IEQ factors—thermal comfort, indoor air quality, luminous environment, acoustics, space, facilities, cleanliness, and layout—function as Basic Factors. While deficiencies in these areas drive dissatisfaction, their adequacy alone does not significantly enhance satisfaction. Notably, exterior view serves as an Excitement Factor in budget accommodations (three stars or below) but transitions to a Basic Factor in luxury settings. Among all IEQ factors, cleanliness, indoor air quality, and acoustics had the strongest negative impacts when underperforming, whereas satisfactory exterior views, cleanliness, and available space positively influenced guest ratings. The COVID-19 pandemic intensified these effects, heightening guest sensitivity to IEQ deficiencies (e.g., poor air quality) while elevating expectations for high-performing attributes like exterior views and available space. Overall, IEQ factors accounted for 32.8 % of customer ratings in budget hotels and 23.9 % in luxury accommodations. The findings underscore the necessity of ensuring satisfactory performance across all IEQ factors, particularly cleanliness and indoor air quality, while strategically enhancing exterior views and spatial configuration to optimize guest satisfaction. These insights provide hospitality managers and policymakers with data-driven guidance for enhancing guest satisfaction and operational resilience in post-pandemic hospitality settings. © 2025 The Author(s)

关键词： Indoor air pollution

来源：评论

学校读者我要写书评

暂无评论

VIBRATION OF HEMI-ELLIPSOIDAL AXISYMMETRICAL DOMES SUBMERGED IN WATER

引用

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART C-JOURNAL OF MECHANICAL engineering SCIENCE 1986年第6期200卷 389-398页

作者： ROSS, CTF JOHNS, T Department of Mechanical Engineering and Naval Architecture Portsmouth Polytechnic

Ten thin-walled domes, of hemi-ellipsoidal form, were vibrated in air and while partially and fully submerged in water. The domes varied in shape from oblate ones of aspect ratio (AR) 0.25 to prolate ones of aspect ratio *** fundamental modal patterns for the oblate domes tended to be of axisymmetric form, while the fundamental modal patterns of the hemispherical and prolate domes tended to be of asymmetric or lobar *** theoretical analysis was carried out by the finite element method, where the motion of the shell structure was represented by three different types of element and the motion of the water was represented by a solid annular *** between theory and experiment was found to be good.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Sustainable refrigerated food transport: searching energy efficient routes

引用

IFAC-PapersOnLine 2018年第11期51卷 618-623页

作者： Meneghetti, Antonella Rold, Gianluca Da Cortella, Giovanni Polytechnic Department of Engineering and Architecture University of Udine Italy

Despite the growing importance of refrigerated food transportation and attention paid to the related sustainability issues, few studies have introduced energy efficiency to guide decision making at operational level. In this research, refrigeration loads are introduced when evaluating fuel consumption for palletized frozen food deliveries from a central refrigerated warehouse, in order to select the best route. In particular, infiltration loads during unloading operations are evaluated basing on the most recent models, as well as transmission loads both during travelling and stops at clients, taking into account changes of outdoor temperatures. A minimum fuel consumption multi-period optimisation model has been developed and solved by Constraint Programming and then applied to a local network of supermarkets. While the traditional minimum travel distance remains the best solution due to the greater impact of travel requirements on total fuel consumption with respect to refrigeration ones, a preferred direction to run the circuit has been highlighted, depending on the different outdoor temperature of time slots triggered during distribution. © 2018

关键词： Energy efficiency

来源：评论

学校读者我要写书评

暂无评论

Curved footbridges supported by a shell obtained through thrust network analysis

引用

Journal of Traffic and Transportation engineering(English Edition) 2019年第1期6卷 65-75页

作者： Luigi Fenu Eleonora Congiu Davide Lavorato Bruno Briseghella Giuseppe Carlo Marano Department of Civil and Environmental Engineering and Architecture University of Cagliari Department of Architecture University of Roma Tre College of Civil Engineering Fuzhou University Department of Sciences of Civil Engineering and Architecture Polytechnic University of Bari

After Maillart's concrete curved arch bridges were built before the Second World War, in the second half of the past century and this century, many curved bridges have been built with both steel and concrete. Conversely, since the construction of Musmeci's shell supported bridge in Potenza, few shell bridges have been constructed. This paper explains how to design a curved footbridge supported by an anticlastic shell by shaping the shell via a thrust network analysis(TNA). By taking advantage of the peculiar properties of anticlastic membranes, the unconventional method of shaping a shell by a TNA is illustrated. The shell top edge that supports the deck has an assigned layout, which is provided by the road curved layout. The form of the bottom edge is obtained by the form-finding procedure as a thrust line, by applying the thrust network analysis(TNA) in a non-standard manner,shaping the shell by applying the boundary conditions and allowing relaxation. The influence of the boundary conditions on the bridge shape obtained as an envelope of thrust lines is investigated. A finite element analysis was performed. The results indicate that the obtained shell form is effective in transferring deck loads to foundations via compressive stresses and taking advantage of concrete mechanical properties.

关键词： Shell footbridges Cantilevered deck Anticlastic shell Thrust network analysis(TNA) Concrete

来源：评论

学校读者我要写书评

暂无评论

SPH numerical investigation of the characteristics of an oscillating hydraulic jump at an abrupt drop

引用

Journal of Hydrodynamics 2018年第1期30卷 106-113页

作者： Diana De Padova Michele Mossa Stefano Sibilla Department of Civil Environmental Land Building Engineering and ChemistryPolytechnic University of Bari Department of Civil Engineering and Architecture University of Pavia

This paper shows the results of the smooth particle hydrodynamics（SPH） modelling of the hydraulic jump at an abrupt drop,where the transition from supercritical to subcritical flow is characterised by several flow patterns depending upon the inflow and tailwater conditions. SPH simulations are obtained by a pseudo-compressible XSPH scheme with pressure smoothing; turbulent stresses are represented either by an algebraic mixing-length model, or by a two-equation k-ε model. The numerical model is applied to analyse the occurrence of oscillatory flow conditions between two different jump types characterised by quasi-periodic oscillation,and the results are compared with experiments performed at the hydraulics laboratory of Bari Technical University. The purpose of this paper is to obtain a deeper understanding of the physical features of a flow which is in general difficult to be reproduced numerically,owing to its unstable character： in particular, vorticity and turbulent kinetic energy fields, velocity, water depth and pressure spectra downstream of the jump, and velocity and pressure cross-correlations can be computed and analysed.

关键词： Hydraulic jumps smoothed particle hydrodynamics（SPH） models oscillating characteristics

来源：评论

学校读者我要写书评

暂无评论

Experimental and analytical procedure for the stability assessment of brick masonry veneer walls

引用

Structures 2025年 78卷

作者： Giada Frappa Samantha Lisetto Margherita Pauletta Polytechnic Department of Engineering and Architecture University of Udine Via delle Scienze 206 Udine 33100 Italy

In the past, brick masonry veneer walls have been extensively used to construct the external envelope of a wide variety of buildings in different countries around the world. Recently, they have also found application in contemporary building construction. Therefore, these walls are very common in existing buildings. However, brick veneer walls frequently exhibit deficiencies due to poor construction practices or inadequate design. This work presents the most significant investigation methods for identifying such deficiencies. Additionally, it proposes an analytical procedure for assessing the out-of-plane stability of these walls in compliance with the Italian Building Code and the recommendations of UNI EN 1996–1–1:2022. The procedure allows for the easy analysis of masonry walls with openings. Additionally, practical tips for quickly calculating seismic forces on non-structural elements are provided. Then, the proposed procedure and tips are used to assess the masonry veneer walls stability of a recent building with visible damage in the masonry cladding system. The results of the investigation campaign carried out on the veneer walls are provided. The effects of thermal variations on the stability of the masonry veneer walls are also considered. Based on the results of the investigations and analyses, the causes of the damages are identified. To ensure that the brick masonry veneer walls meet the safety requirements prescribed by the standards, interventions are also proposed.

关键词： Brick masonry veneer walls Out-of-plane behavior Stability assessment Seismic action Thermal variation Deficiencies

来源：评论

学校读者我要写书评

暂无评论

Glazed tiles produced using paper sludge, glass cullet and a natural red clay: an experimental study

引用

International Journal of Environmental Studies 2018年第6期75卷 903-912页

作者： Furlani, Erika Maschio, Stefano Polytechnic Department of Engineering and Architecture University of Udine Udine Italy

The paper describes the production, in single fast firing, of tiles containing 30 wt% of a natural red clay and a mixture of 42 wt% of paper mill sludge and 28 wt% of glass cullet which were coated with a commercial ‘matt white’ glaze. Fired materials have been characterized as a function of the top temperature (1090 or 1140 °C) reached at the top of the fast sintering process made by an industrial roller kiln. It has been observed that tiles fired at 1090 °C display the best overall performances because the matt glaze well covers the substrate, thus ensuring that the mechanical and physical properties of the tiles conform to the official standard. © 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group.

关键词： Sintering

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：