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Constructing Electron Microscope Labs: Challenges and Solutions
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作者 Limei Cha Markus Walkling-Ribeiro +2 位作者 Zhenxi Guo Yaron Kauffman Constance Van Horne 《Journal of Building Construction and Planning Research》 2024年第3期53-68,共16页
The construction of advanced laboratories for precision instruments, such as electron microscopes, involves unique challenges that are influenced by the specific environmental conditions required for optimal functiona... The construction of advanced laboratories for precision instruments, such as electron microscopes, involves unique challenges that are influenced by the specific environmental conditions required for optimal functionality. These include mitigating interference from magnetic fields and vibrations, which are critical for maintaining the precision and accuracy of the instruments used. This study aims to offer enhanced project management strategies and detailed construction solutions that address the environmental and technical needs specific to electron microscopy labs, thereby facilitating effective lab operations and extending the lifecycle of high-end precision instruments. Case studies of existing laboratory constructions, onsite investigations, and comprehensive reviews of the technical and environmental requirements provide the basis for a best practice for constructing sophisticated electron microscopy labs. The approach integrates both pre-construction planning and post-construction adjustments to create optimal operational environments. The findings suggest that successful lab constructions are those that incorporate thorough onsite assessments, strategic location choices, and the use of advanced construction materials and techniques specifically designed to counteract environmental challenges like magnetic and vibration interferences. Actionable guidelines for both planning and executing the construction of electron microscope labs highlighted in this tutorial are intended as an important resource to troubleshoot or upgrade existing lab facilities and to consult in preparation of future lab construction projects. 展开更多
关键词 Laboratory Construction Development Strategies MANAGEMENT Case Study Electron Microscope Magnetic Shielding VIBRATION
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Acknowledging the Challenges of Constructing in Regions with Low Temperature
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作者 Md Ratan Bhuiyan Md Rabiul Azam +2 位作者 Badal Hossain Md Taruk Aziz Md Abdullah Al Galib 《World Journal of Engineering and Technology》 2023年第4期902-916,共15页
This research paper provides an overview of low-temperature construction processes with an emphasis on the challenges that the sector faces and the creative solutions created to deal with them. Low-temperature constru... This research paper provides an overview of low-temperature construction processes with an emphasis on the challenges that the sector faces and the creative solutions created to deal with them. Low-temperature construction has particular challenges with regard to technology, materials, worker safety and technological development. It highlights the necessity of customized regulations and procedures aimed at improving the sustainability and efficiency of construction in regions with low temperatures. 展开更多
关键词 CONSTRUCTION Low Temperature CHALLENGES MATERIALS Safety & Technological Development
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A Simplified Graphical Procedure for Constructing a 10˚or 20˚Angle
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作者 Lyndon O. Barton 《Advances in Pure Mathematics》 2023年第7期442-448,共7页
This paper presents a simplified graphical procedure for constructing, using an unmarked straightedge and a compass only, a 10˚ to 20˚ angle, which is in other words, trisecting a 30˚ or 60˚ angle. The procedure, when... This paper presents a simplified graphical procedure for constructing, using an unmarked straightedge and a compass only, a 10˚ to 20˚ angle, which is in other words, trisecting a 30˚ or 60˚ angle. The procedure, when applied to the 30˚ and 60˚ angles that have been “proven” to be not trisectable, produced a construction having the identical angular relationship with Archimedes’ Construction, in which the required trisection angles were found to be 10.00000˚ and 20.00000˚ respectively (i.e. exactly one-third of the given angle or ∠E’MA = 1/3∠E’CG). Based on this identical angular relationship as well as the numerical results obtained, one can only conclude that the geometric requirements for arriving at an exact trisection of the 30˚ or 60˚ angle, and therefore the construction of a 10˚ or 20˚ angle, have been met, notwithstanding the theoretical proofs of Wantzel, Dudley, and others. Thus, the solution to the age-old trisection problem, with respect to these two angles, has been accomplished. 展开更多
关键词 Archimedes’ Construction College Geometry Angle Trisection Trisection of an Angle Famous Problems in Mathematics. Geometer’s Sketch Pad Mechanisms Mechanism Analysis Kinematics Trisector
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Rapid Constructing a Genetic Linkage Map by AFLP Technique and Mapping a New Gene tms5 被引量:9
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作者 贾建航 李传友 +1 位作者 邓启云 王斌 《Acta Botanica Sinica》 CSCD 2003年第5期614-620,共7页
In this study, we reported the repaid construction of a molecular marker linkage map of rice (Oryza sativa L.). An F-2 population from the cross between Annong S-1 and Nanjing 11 was used to construct a genetic linkag... In this study, we reported the repaid construction of a molecular marker linkage map of rice (Oryza sativa L.). An F-2 population from the cross between Annong S-1 and Nanjing 11 was used to construct a genetic linkage map of rice. Total of 142 newly screened AFLP markers and 30 anchor markers (25 SSR markers and 5 RFLP markers) were mapped on the 12 chromosomes covering 1537.4 cM of rice genome. The average interval between these markers was 9.0 cM. The total work which usually was finished in more than one year was finished within only 3 months by one person. This is the first plant AFLP map developed in China. A new thermosensitive genic male sterile gene in rice, tms5, was Egged and mapped onto chromosome 2 during the development of the linkage map. 展开更多
关键词 AFLP rapid constructing genetic linkage map rice thermosensitive genic male sterile gene tms5
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Analysis on the Necessity and Feasibility of Implementing the Strategy of "Protecting Farmland in Flatland Areas and Constructing Mountainous Cities" in Yunnan Province 被引量:3
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作者 贺一梅 杨子生 邹金浪 《Agricultural Science & Technology》 CAS 2015年第4期769-773,共5页
Yunnan is one of the most typical mountalnous provinces in western Chi-na. For the geographical features of mountalnous areas accounting for most parts and fIatIand areas accounting for smal parts, the contradiction b... Yunnan is one of the most typical mountalnous provinces in western Chi-na. For the geographical features of mountalnous areas accounting for most parts and fIatIand areas accounting for smal parts, the contradiction between farmIand protection and construction guarantee is very prominent. In the first half of 2011, Yunnan Province estabIished creativeIy the strategy of &quot;protecting farmIand in fIat-Iand areas and constructing mountalnous cities&quot; (hereinafter referred to as the strat-egy of &quot;constructing mountalnous cities&quot;), which was almed at protecting effectiveIy the Iimited and high quality arabIe Iand resources in fIatIand area and providing new construction area for new type of urbanization and industrialization, so as to achieve win-win situation between arabIe Iand protection and urbanization deveIopment. Im-pIementing this strategy in Yunnan Province is feasibIe, malnIy in the Iarge deveIop-ment potentials in the gentIe gradient between 8° to 25°. The gentIe sIope area be-tween 8° to 25° occupies 51% of the total Iand area in Yunnan Province, which is almost 140 times of the area of urban construction Iand in Yunnan in 2009. The surrounding areas of fIatIand or maln town in most counties (cities, regions) dis-tribute with different sizes of Iow hiI s and gentIe sIopes, thus mountalnous construc-tion Iand reserves are abundant, which benefits for impeI ing the strategy of &quot;con-structing mountalnous cities&quot; in the Iight of Iocal conditions. 展开更多
关键词 constructing mountalnous citles STRATEGY NECESSITY Feasibliity Yunnan Province
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Process,Material,and Regulatory Considerations for 3D Printed Medical Devices and Tissue Constructs 被引量:1
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作者 Wei Long Ng Jia An Chee Kai Chua 《Engineering》 SCIE EI CAS CSCD 2024年第5期146-166,共21页
Three-dimensional(3D)printing is a highly automated platform that facilitates material deposition in a layer-by-layer approach to fabricate pre-defined 3D complex structures on demand.It is a highly promising techniqu... Three-dimensional(3D)printing is a highly automated platform that facilitates material deposition in a layer-by-layer approach to fabricate pre-defined 3D complex structures on demand.It is a highly promising technique for the fabrication of personalized medical devices or even patient-specific tissue constructs.Each type of 3D printing technique has its unique advantages and limitations,and the selection of a suitable 3D printing technique is highly dependent on its intended application.In this review paper,we present and highlight some of the critical processes(printing parameters,build orientation,build location,and support structures),material(batch-to-batch consistency,recycling,protein adsorption,biocompatibility,and degradation properties),and regulatory considerations(sterility and mechanical properties)for 3D printing of personalized medical devices.The goal of this review paper is to provide the readers with a good understanding of the various key considerations(process,material,and regulatory)in 3D printing,which are critical for the fabrication of improved patient-specific 3D printed medical devices and tissue constructs. 展开更多
关键词 3D printing BIOPRINTING BIOFABRICATION Medical devices Tissue constructs
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Efficiency and effectiveness of systems for the treatment of domestic wastewater based on subsurface flow constructed wetlands in Jarabacoa, Dominican Republic 被引量:1
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作者 Yvelisse Pérez Enmanuel Vargas +3 位作者 Daniel Garcia-Cortes William Hernandez Humberto Checo Ulises Jauregui-Haza 《Water Science and Engineering》 EI CAS CSCD 2024年第2期118-128,共11页
Constructed wetlands(CwW)are well known nature-based systems for water treatment.This study evaluated the efficiency and effectiveness of seven domestic wastewater treatment systems based on horizontal flow CWs in Jar... Constructed wetlands(CwW)are well known nature-based systems for water treatment.This study evaluated the efficiency and effectiveness of seven domestic wastewater treatment systems based on horizontal flow CWs in Jarabacoa,the Dominican Republic.The results showed that the CWs were efficient in reducing the degree of contamination of wastewater to levels below the Dominican wastewater discharge standards for parameters such as the 5-day biochemical oxygen demand(BOD5)and chemical oxygen demand,but not for the removal of phosphorus and fecal coliforms.In addition,a horizontal flow subsurface wetland in the peri-urban area El Dorado was evaluated in terms of the performance of wastewater treatment in tropical climatic conditions.The concentrations of heavy metals,such as zinc,copper,chromium,and iron,were found to decrease in the effluent of the wetland,and the concentrations for nickel and manganese tended to increase.The levels of heavy metals in the effluent were lower than the limit values of the Dominican wastewater discharge standards.The construction cost of these facilities was around 200 USD per population equivalent,similar to the cost in other countries in the same region.This study suggested some solutions to the improved performance of CWs:selection of a microbial flora that guarantees the reduction of nitrates and nitrites to molecular nitrogen,use of endemic plants that bioaccumulate heavy metals,combination of constructed wetlands with filtration on activated carbon,and inclusion of water purification processes that allow to evaluate the reuse of treated water. 展开更多
关键词 Domestic wastewater Constructed wetland BOD COD PATHOGENS Heavy metals
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Study on Urban Construction Land Suitability Evaluation in Southwestern Mountainous Areas of Yunnan Province Based on the Strategy of "Protecting Farmland in Flatland Areas and Constructing Mountainous Cities" : A Case in Lianghe County 被引量:4
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作者 贺一梅 杨子生 +2 位作者 张博胜 邓有旺 张德省 《Agricultural Science & Technology》 CAS 2014年第10期1774-1777,1780,共5页
According to the particularity of towns' construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat ... According to the particularity of towns' construction in the southwestern mountainous areas of Yunnan Province, this study has built constructive land suit- ability evaluation index system which is different to flat area. Then this study deter- mined single evaluation factors index and comprehensive suitability index using "ex- treme conditions method" and "suitability index method", and analyzed and assessed the constructive land suitability on each evaluation unit polygons and its suitability level by using GIS software. Taking Lianghe County of Dehong Dai-Jingpo Au- tonomous Prefecture as an example to evaluate land suitability in Lianghe County's main towns around the gentle slope, the results show, in the evaluation area, the area of land suitable for construction and unsuitable for construction respectively ac- count 73.58% and 26.42%. And first-class, second and third-class of land suitable for construction should be composited at the ratio of about 11:49:40. The suitability evaluation index system and method developed in this paper is applicable for evalu- ating the construction land suitability in mountainous areas of southwest Yunnan Province, and will provide theoretical and technical support for land policy measures which strengthen the protection of farmland and promote the scientific development of urbanization in Yunnan Province and even similar mountainous areas of the whole China. 展开更多
关键词 Mountainous area Constructive land Suitability evaluation Comprehensive suitability index Southwestern Yunnan Province
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Research Progress and Prospects of Total Factor Productivity in the Construction Industry 被引量:1
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作者 Chen WANG Shijie YU +2 位作者 Chenhao LIANG Lidan CAI Xiaohong XIONG 《Asian Agricultural Research》 2024年第7期39-41,共3页
The high-quality development of the construction industry fundamentally stems from the significant improvement of total factor productivity.Therefore,it is of crucial significance for promoting the development of the ... The high-quality development of the construction industry fundamentally stems from the significant improvement of total factor productivity.Therefore,it is of crucial significance for promoting the development of the construction industry to a higher level by scientifically and accurately measuring the total factor productivity of the construction industry and deeply analyzing the influencing factors behind it.Based on a comprehensive consideration of research methods and influencing factors,this paper systematically reviews the existing relevant literature on total factor productivity in the construction industry,aiming to reveal the current research development trend in this field and point out potential problems.This effort aims to provide a solid theoretical foundation and valuable reference for further in-depth research,and jointly promote the continuous progress and development of total factor productivity research in the construction industry. 展开更多
关键词 Construction industry Total factor productivity Research progress Influence factor Theoretical basis
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基于Construct 3的射击类游戏设计与开发——以飞机大战为例
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作者 刘树林 杨艳瑜 李博 《微型电脑应用》 2024年第2期14-17,共4页
Construct 3作为小而精的H5跨平台游戏引擎,强大的交互性和用户友好性使其在2D游戏开发方面独具优势。借助Construct 3重构经典射击类游戏“飞机大战”,通过Event Sheet实现游戏中背景循环滚动、动画导入、角色创建与随机运动、游戏难... Construct 3作为小而精的H5跨平台游戏引擎,强大的交互性和用户友好性使其在2D游戏开发方面独具优势。借助Construct 3重构经典射击类游戏“飞机大战”,通过Event Sheet实现游戏中背景循环滚动、动画导入、角色创建与随机运动、游戏难度控制、游戏变量控制等主要功能。经过测试,游戏可打包发布成Web、移动设备和PC端.exe格式,游戏交互、特效运行流畅,游戏变量与难度控制处于合理范围。 展开更多
关键词 Construct 3 游戏开发 射击类游戏
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Properties and Characteristics of Regolith-Based Materials for Extraterrestrial Construction
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作者 Cheng Zhou Yuyue Gao +4 位作者 Yan Zhou Wei She Yusheng Shi Lieyun Ding Changwen Miao 《Engineering》 SCIE EI CAS CSCD 2024年第6期159-181,共23页
The construction of extraterrestrial bases has become a new goal in the active exploration of deep space.Among the construction techniques,in situ resource-based construction is one of the most promising because of it... The construction of extraterrestrial bases has become a new goal in the active exploration of deep space.Among the construction techniques,in situ resource-based construction is one of the most promising because of its good sustainability and acceptable economic cost,triggering the development of various types of extraterrestrial construction materials.A comprehensive survey and comparison of materials from the perspective of performance was conducted to provide suggestions for material selection and optimization.Thirteen types of typical construction materials are discussed in terms of their reliability and applicability in extreme extraterrestrial environment.Mechanical,thermal and optical,and radiation-shielding properties are considered.The influencing factors and optimization methods for these properties are analyzed.From the perspective of material properties,the existing challenges lie in the comprehensive,long-term,and real characterization of regolith-based construction materials.Correspondingly,the suggested future directions include the application of high-throughput characterization methods,accelerated durability tests,and conducting extraterrestrial experiments. 展开更多
关键词 Extraterrestrial construction Characterization Mechanical property Thermal property Optical property Radiation-shielding
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Evaluating the performance of genomic selection on purebred population by incorporating crossbred data in pigs
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作者 Jun Zhou Qing Lin +10 位作者 Xueyan Feng Duanyang Ren Jinyan Teng Xibo Wu Dan Wu Xiaoke Zhang Xiaolong Yuan Zanmou Chen Jiaqi Li Zhe Zhang Hao Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期639-648,共10页
Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it... Genomic selection(GS)has been widely used in livestock,which greatly accelerated the genetic progress of complex traits.The population size was one of the significant factors affecting the prediction accuracy,while it was limited by the purebred population.Compared to directly combining two uncorrelated purebred populations to extend the reference population size,it might be more meaningful to incorporate the correlated crossbreds into reference population for genomic prediction.In this study,we simulated purebred offspring(PAS and PBS)and crossbred offspring(CAB)base on real genotype data of two base purebred populations(PA and PB),to evaluate the performance of genomic selection on purebred while incorporating crossbred information.The results showed that selecting key crossbred individuals via maximizing the expected genetic relationship(REL)was better than the other methods(individuals closet or farthest to the purebred population,CP/FP)in term of the prediction accuracy.Furthermore,the prediction accuracy of reference populations combining PA and CAB was significantly better only based on PA,which was similar to combine PA and PAS.Moreover,the rank correlation between the multiple of the increased relationship(MIR)and reliability improvement was 0.60-0.70.But for individuals with low correlation(Cor(Pi,PA or B),the reliability improvement was significantly lower than other individuals.Our findings suggested that incorporating crossbred into purebred population could improve the performance of genetic prediction compared with using the purebred population only.The genetic relationship between purebred and crossbred population is a key factor determining the increased reliability while incorporating crossbred population in the genomic prediction on pure bred individuals. 展开更多
关键词 PIGS crossbred population genomic selection reference population construction relationship
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Micromechanical testing and property upscaling of planetary rocks:A critical review
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作者 Yiwei Liu Guoping Zhang +1 位作者 Jiangmei Qiao Xuhai Tang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1217-1241,共25页
Knowledge of the mechanical behavior of planetary rocks is indispensable for space explorations.The scarcity of pristine samples and the irregular shapes of planetary meteorites make it difficult to obtain representat... Knowledge of the mechanical behavior of planetary rocks is indispensable for space explorations.The scarcity of pristine samples and the irregular shapes of planetary meteorites make it difficult to obtain representative samples for conventional macroscale rock mechanics experiments(macro-RMEs).This critical review discusses recent advances in microscale RMEs(micro-RMEs)techniques and the upscaling methods for extracting mechanical parameters.Methods of mineralogical and microstructural analyses,along with non-destructive mechanical techniques,have provided new opportunities for studying planetary rocks with unprecedented precision and capabilities.First,we summarize several mainstream methods for obtaining the mineralogy and microstructure of planetary rocks.Then,nondestructive micromechanical testing methods,nanoindentation and atomic force microscopy(AFM),are detailed reviewed,illustrating the principles,advantages,influencing factors,and available testing results from literature.Subsequently,several feasible upscaling methods that bridge the micro-measurements of meteorite pieces to the strength of the intact body are introduced.Finally,the potential applications of planetary rock mechanics research to guiding the design and execution of space missions are environed,ranging from sample return missions and planetary defense to extraterrestrial construction.These discussions are expected to broaden the understanding of the microscale mechanical properties of planetary rocks and their significant role in deep space exploration. 展开更多
关键词 METEORITES Planetary rock mechanics Non-destructive testing Upscaling method Extraterrestrial construction Space exploration
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Construction Activity Analysis of Workers Based on Human Posture Estimation Information
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作者 Xuhong Zhou Shuai Li +2 位作者 Jiepeng Liu Zhou Wu Yohchia Frank Chen 《Engineering》 SCIE EI CAS CSCD 2024年第2期225-236,共12页
Identifying workers’construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress.However,current activity analysis methods for construction workers rely solely... Identifying workers’construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress.However,current activity analysis methods for construction workers rely solely on manual observations and recordings,which consumes considerable time and has high labor costs.Researchers have focused on monitoring on-site construction activities of workers.However,when multiple workers are working together,current research cannot accu rately and automatically identify the construction activity.This research proposes a deep learning framework for the automated analysis of the construction activities of multiple workers.In this framework,multiple deep neural network models are designed and used to complete worker key point extraction,worker tracking,and worker construction activity analysis.The designed framework was tested at an actual construction site,and activity recognition for multiple workers was performed,indicating the feasibility of the framework for the automated monitoring of work efficiency. 展开更多
关键词 Pose estimation Activity analysis Object tracking Construction workers Automatic systems
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Promoting grain production through high-standard farmland construction:Evidence in China
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作者 Shuai Hao Guogang Wang +4 位作者 Yantao Yang Sicheng Zhao Shengnan Huang Liping Liu Huanhuan Zhang 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期324-335,共12页
Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capa... Food security is a strategic priority for a country’s economic development.In China,high-standard farmland construction(HSFC)is an important initiative to stabilize grain production and increase grain production capacity.Based on panel data from 31 sample provinces,autonomous regions,and municipalities in China from 2005–2017,this study explored the impact of HSFC on grain yield using the difference-in-differences(DID)method.The results showed that HSFC significantly increased total grain production,which is robust to various checks.HSFC increased grain yield through three potential mechanisms.First,it could increase the grain replanting index.Second,it could effectively reduce yield loss due to droughts and floods.Last,HSFC could strengthen the cultivated land by renovating the low-and medium-yielding fields.Heterogeneity analysis found that the HSFC farmland showed a significant increase in grain yield only in the main grain-producing areas and balanced areas.In addition,HSFC significantly increased the yields of rice,wheat,and maize while leading to a reduction in soybean yields.The findings suggest the government should continue to promote HSFC,improve construction standards,and strictly control the“non-agriculturalization”and“non-coordination”of farmland to increase grain production further.At the same time,market mechanisms should be used to incentivize soybean farming,improve returns and stabilize soybean yields. 展开更多
关键词 high-standard farmland farmland construction food security food production area DIFFERENCE-IN-DIFFERENCES
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Modelling the water diversion of a sustainable cover system under humid climates
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作者 Haowen Guo Charles Wang Wai Ng +2 位作者 Qi Zhang Chuanxiang Qu Liwen Hu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2429-2440,共12页
Extreme rainfall significantly threatens the safety of the landfill cover system,especially under humid climates.This study aims to provide design recommendations for a sustainable landfill cover system consisting of ... Extreme rainfall significantly threatens the safety of the landfill cover system,especially under humid climates.This study aims to provide design recommendations for a sustainable landfill cover system consisting of a low-permeability soil layer underlying a two-layer capillary barrier for humid climates.First,the numerical back-analysis was conducted for verification against a series of flume model tests.Then,a parametric study was performed to investigate the effects of inclination angle,particle size and layer thickness on the lateral diversion length(DL)of the three-layer cover system under the 100-year return period rainfall of humid climates.The results show that the water lateral DL of the cover system can be greatly enhanced by increasing the inclination angle from 3°to 18°.Moreover,the bottom layer of the cover system with a coarser d10 was more susceptible to the impact of the heavy rainfall,while this can be alleviated by increasing the thickness of the bottom layer.A dimensionless number,defined as the ratio of thickness and d_(10) of the bottom layer,is proposed for designing lateral diversion of the three-layer cover system under humid climates.To preserve the maximum DL,it is suggested that the proposed dimensionless number should be larger than 95 and 110 for the design of rainfall events with 50-year and 100-year return periods for humid climates,respectively. 展开更多
关键词 Unsaturated soil RECYCLING Construction waste Three-layer landfill cover Water infiltration
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Robotic reconstructive surgery: The time has arrived
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作者 Brian W.Chao 《Asian Journal of Urology》 CSCD 2024年第3期339-340,F0002,共3页
Thank you to the Asian Journal of Urology(AJU)for the honor of allowing me to be the guest editor for this special focus section on robotic urinary tract reconstruction.This topic has been a large focus for me in my c... Thank you to the Asian Journal of Urology(AJU)for the honor of allowing me to be the guest editor for this special focus section on robotic urinary tract reconstruction.This topic has been a large focus for me in my career;in my pursuit of knowledge in this new sub-field of urology,I have been so fortunate to have met so many talented surgeons who share a similar passion.The urinary tract spans a large anatomical region,and due to the large variety of conditions that affect it,an endless variety of functional and structural urologic problems can arise.Urologists have always been adept surgeons capable of operating in various anatomical spaces and have embraced technological innovation.Historically,the trend has moved from open surgery to endoscopic treatment;however,many patients with reconstructive needs remain untreated or sub-optimally managed. 展开更多
关键词 SURGERY CONSTRUCTIVE EDITOR
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Impacts of hydropower-induced flow alterations on composition and diversity of riparian vegetation in the Western Himalayas: A case study in Uttarakhand, India
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作者 Dharmveer KAINTURA Sabyasachi DASGUPTA Dhanpal Singh CHAUHAN 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1272-1286,共15页
The increasing demand for water and energy resources has led to widespread dam construction,particularly in ecologically sensitive regions like the Himalayan Range.This study focuses on the Uttarakhand state in the We... The increasing demand for water and energy resources has led to widespread dam construction,particularly in ecologically sensitive regions like the Himalayan Range.This study focuses on the Uttarakhand state in the Western Himalayas,where hydroelectric projects(HEPs)have significantly altered river flow regimes.The research investigates the impact of flow alterations on the composition and structure of riparian vegetation in the Garhwal Himalayas,specifically analysing four rivers regulated by hydroelectric projects.Utilizing the paired-reach comparison method,control(undisturbed),diverted(downstream of barrage/dam),and altered flow conditions(downstream of water outlet)were examined.The research reveals diverse and unique riparian ecosystems,with 89 genera and 113 taxa identified,showcasing the dominance of families like Asteraceae and Lamiaceae.The study unveils the structural importance of key species such as Berberis asiatica and Artemisia nilagirica.The density,diversity,and richness of shrub and herb species vary significantly across flow conditions.Notably,altered flow conditions demonstrate resilience in vegetation structure,while diverted conditions exhibit decreased species richness and density.The study emphasizes the importance of nuanced environmental flow management for mitigating adverse effects on riparian biodiversity in the fragile Himalayan region.These findings contribute to the global discourse on dam impacts and riparian ecology,shedding light on the complexities of this dynamic relationship in a vulnerable ecosystem. 展开更多
关键词 Dam construction Water stress Western Himalayas Disturbed flow regimes Riparian ecosystem
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Friction Characteristics Between Marine Clay and Construction Materials
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作者 KOU Hailei HUANG Jiaming CHENG Yang 《Journal of Ocean University of China》 CAS CSCD 2024年第2期427-437,共11页
Structure-soil interface friction characteristics is of importance to investigate the interaction between engineering structures and soils,especially for offshore structures.The interface friction behavior between mar... Structure-soil interface friction characteristics is of importance to investigate the interaction between engineering structures and soils,especially for offshore structures.The interface friction behavior between marine clay and structural materials with different roughness was studied in this paper by using 3D optical scanning tests,a modified direct shear device and numerical simulation.Relationships between the surface roughness of structures,water content and interface friction angle were presented by model tests.The increase of water contents decreased the interface friction angles.For interfaces with different roughness,the interface friction angles will be smaller than that of the soil when the water content exceeds a certain value.The roughness of the interface and the water content of the soil are mutually coupled to influence the coefficient of friction(COF).This paper proposed a Finite Element Method(FEM)to simulate the interface direct shear tests of structures with different roughness.The surface models with different roughness are established based on the structure data obtained by 3D scanning.The Coupled Eulerian-Lagrangian(CEL)approach was employed to analyse soils sheared by irregular surfaces.The interface behavior for interfaces with different roughness under cyclic shear stresses was analyzed by FEM. 展开更多
关键词 marine clay construction material interface friction behavior surface roughness Finite Element Method
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Mechanical properties and damage evolution characteristics of waste tire steel fiber-modified cemented paste backfill
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作者 Shenggen Cao Chiyuan Che +4 位作者 Yun Zhang Changhao Shan Yang Liu Changzheng Zhao Shuyu Du 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第7期909-924,共16页
During the process of constructional backfill mining,the cemented paste backfill(CPB)typically exhibits a high degree of brittleness and limited resistance to failure.In this study,the mechanical and damage evolution ... During the process of constructional backfill mining,the cemented paste backfill(CPB)typically exhibits a high degree of brittleness and limited resistance to failure.In this study,the mechanical and damage evolution characteristics of waste tire steel fiber(WTSF)-modified CPB were studied through uniaxial compression tests,acoustic emission(AE)tests,and scanning electron microscopy(SEM).The results showed that the uniaxial compressive strength(UCS)decreased when the WTSF content was 0.5%,1%,and 1.5%.When the WTSF content reached 1%,the UCS of the modified CPB exhibited a minimal decrease(0.37 MPa)compared to that without WTSF.When the WTSF content was 0.5%,1%,and 1.5%,peak strain of the WTSF-modified CPB increased by 18%,31.33%,and 81.33%,while the elastic modulus decreased by 21.31%,26.21%,and 45.42%,respectively.The addition of WTSF enhances the activity of AE events in the modified CPB,resulting in a slower progression of the entire failure process.After the failure,the modified CPB retained a certain level of load-bearing capacity.Generally,the failure of the CPB was dominated by tensile cracks.After the addition of WTSF,a gradual increase in the proportion of tensile cracks was observed upon loading the modified CPB sample to the pore compaction stage.The three-dimensional localization of AE events showed that the WTSF-modified CPB underwent progressive damage during the loading,and the samples still showed good integrity after failure.Additionally,the response relationship between energy evolution and damage development of WTSF-modified CPB during uniaxial compression was analyzed,and the damage constitutive model of CPB samples with different WTSF contents was constructed.This study provides a theoretical basis for the enhancement of CPB modified by adding WTSF,serving as a valuable reference for the design of CPB constructional backfill. 展开更多
关键词 Constructional backfill Cemented paste backfill Waste tire steel fiber Acoustic emission Damage characteristics
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