Automatic control technology is the basis of road robot improvement,according to the characteristics of construction equipment and functions,the research will be input type perception from positioning acquisition,real...Automatic control technology is the basis of road robot improvement,according to the characteristics of construction equipment and functions,the research will be input type perception from positioning acquisition,real-world monitoring,the process will use RTK-GNSS positional perception technology,by projecting the left side of the earth from Gauss-Krueger projection method,and then carry out the Cartesian conversion based on the characteristics of drawing;steering control system is the core of the electric drive unmanned module,on the basis of the analysis of the composition of the steering system of unmanned engineering vehicles,the steering system key components such as direction,torque sensor,drive motor and other models are established,the joint simulation model of unmanned engineering vehicles is established,the steering controller is designed using the PID method,the simulation results show that the control method can meet the construction path demand for automatic steering.The path planning will first formulate the construction area with preset values and realize the steering angle correction during driving by PID algorithm,and never realize the construction-based path planning,and the results show that the method can control the straight path within the error of 10 cm and the curve error within 20 cm.With the collaboration of various modules,the automatic construction simulation results of this robot show that the design path and control method is effective.展开更多
The development of the construction industry is shifting towards low-carbon construction,so it is necessary to improve and optimize related construction concepts,methods,and processes.By improving resource and energy ...The development of the construction industry is shifting towards low-carbon construction,so it is necessary to improve and optimize related construction concepts,methods,and processes.By improving resource and energy control efficiency in building projects,minimizing construction waste,and reducing environmental impact,a foundation for the sustainable development of the industry can be established.This paper mainly analyzes the significance of low-carbon energy-saving construction technology and the control factors of construction,summarizes the status quo of the development of building energy-saving construction,and puts forward strategies for applying building energy-saving construction technology.These strategies serve to achieve low-carbon and energy-saving goals to promote the healthy development of energy-saving construction.展开更多
Urbanization has led to the rapid development of the construction industry.However,this has also led to higher requirements for the construction engineering management.Other than the quality monitoring of engineering ...Urbanization has led to the rapid development of the construction industry.However,this has also led to higher requirements for the construction engineering management.Other than the quality monitoring of engineering construction,the energy-saving properties of the building should also be considered.Therefore,a scientific management approach should be adopted to improve green building management.This paper primarily examines the importance of quality management in green building construction,along with the factors influencing it.It also identifies the quality issues present in current green building construction.Finally,it proposes measures for quality management in the green building construction process to facilitate the industry’s healthy development.展开更多
In recent years,China has made significant progress in the construction of highways,resulting in an improved highway network that has provided robust support for economic and social development.However,the rapid expan...In recent years,China has made significant progress in the construction of highways,resulting in an improved highway network that has provided robust support for economic and social development.However,the rapid expansion of highway construction,power supply,and distribution has led to several challenges in mechanical and electrical engineering technology.Ensuring the safe,stable,and cost-effective operation of the power supply and distribution system to meet the diverse requirements of highway operations has become a pressing issue.This article takes an example of a highway electromechanical engineering power supply and distribution construction project to provide insight into the construction process of highway electromechanical engineering power supply and distribution technology.展开更多
As the urban populations grow,the number and size of subway construction projects are increasing while also meeting higher construction standards.So,subway construction projects must have a better understanding of con...As the urban populations grow,the number and size of subway construction projects are increasing while also meeting higher construction standards.So,subway construction projects must have a better understanding of construction technology.This article focuses on the construction technology of the subway tunnel expansion under the bridge foundation.By analyzing the engineering characteristics of the bridge foundation and using a project as an example,this article provides a detailed discussion of the construction process of tunnel expansion under a bridge foundation.This article aims to serve as a reference for subway tunnel construction in China to ensure the key points of construction technology are understood,thus improving construction quality and laying a solid technical foundation for the sustainable development of urban rail engineering.展开更多
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
Introduction: Work-related accidents are frequent and serious in the construction sector. The aim of the study was to determine the frequency and factors associated with occupational accidents on the construction site...Introduction: Work-related accidents are frequent and serious in the construction sector. The aim of the study was to determine the frequency and factors associated with occupational accidents on the construction site of a referral hospital in Benin. Methods: A cross-sectional study was carried out. The sample size was calculated using the Schwartz form adjusted for the number of workers on site and was 129 workers. Random sampling was used. The dependent variable was work-related accidents. The other variables were socio-demographic and occupational characteristics. Data were collected through a questionnaire survey. Medians and proportions were calculated. An association was sought using Chi-square and Fisher tests with a threshold of p Results: A total of 132 workers were included. Their median age was 30 years with an ITQ of [27 - 38];men were the most represented 126 (95.45%) with a level of education higher than or equal to high school in 101 (76.52%) and in the majority with a permanent status 85 (64.39%). Seniority of more than 5 years was observed in 92 (69.7%). Workers working more than 8 hours of overtime per week numbered 57 (43.18%). Exposure to vibrating objects was 49 (37.12%). In terms of psychosocial constraints, 82.58% had high psychological demands;79.53% low decision-making latitude;50.76% low social support. The frequency of work-related accidents was 6.82%, and the only associated factor was the type of worker (p = 0.016). On the other hand, there were 10.2% accidents among workers handling vibrating objects versus 4.98% among those not using them. With regard to psychosocial constraints, the following frequencies were recorded respectively: 6.42% among those with high psychological demand versus 8.7% among those with low psychological demand;7.62% among those with low decision-making latitude versus 3.7% among those with high decision-making latitude;8.96% among those with low social support versus 4.62% among those with high support. Conclusion: Work-related accidents on construction sites must be avoided by all possible means including the management of psychosocial constraints.展开更多
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
Taking the changes of construction land in Wan’an County over the years as the research object,the quantity and spatial characteristics of construction land in Wan’an County were analyzed,and the overall situation a...Taking the changes of construction land in Wan’an County over the years as the research object,the quantity and spatial characteristics of construction land in Wan’an County were analyzed,and the overall situation and regional differences of construction land utilization in Wan’an County were revealed.From the aspects of main influencing factors such as land use structure,land use intensity,land input intensity and output benefit,an evaluation indicator system was established to evaluate the economical and intensive use level of construction land in Wan’an County.The results show that the score of the economical and intensive use level of construction land in Wan’an County was 56.92,which was the lowest among all the districts and counties in Ji’an City.Based on the evaluation results,the corresponding economizing and intensive strategies were put forward,and the safeguard measures for its implementation were explored.The purpose is to provide some support for the preparation of territorial spatial planning,the delineation of urban development boundaries,and the potential exploitation of construction land stock,hoping to improve the utilization efficiency and benefit of construction land in Wan’an County,and promote the economic growth of Wan’an County to the stage of high-quality development.展开更多
This research is concentrated on the longitudinal vibration of a tapered pipe pile considering the vertical support of the surrounding soil and construction disturbance.First,the pile-soil system is partitioned into f...This research is concentrated on the longitudinal vibration of a tapered pipe pile considering the vertical support of the surrounding soil and construction disturbance.First,the pile-soil system is partitioned into finite segments in the vertical direction and the Voigt model is applied to simulate the vertical support of the surrounding soil acting on the pile segment.The surrounding soil is divided into finite ring-shaped zones in the radial direction to consider the construction disturbance.Then,the shear complex stiffness at the pile-soil interface is derived by solving the dynamic equilibrium equation for the soil from the outermost to innermost zone.The displacement impedance at the top of an arbitrary pile segment is obtained by solving the dynamic equilibrium equation for the pile and is combined with the vertical support of the surrounding soil to derive the displacement impedance at the bottom of the upper adjacent segment.Further,the displacement impedance at the pile head is obtained based on the impedance function transfer technique.Finally,the reliability of the proposed solution is verified,followed by a sensitivity analysis concerning the coupling effect of the pile parameters,construction disturbance and the vertical support of the surrounding soil on the displacement impedance of the pile.展开更多
Cochin Port is an all-weather port situated within a protected natural harbour,just 11 km away from mainland shipping route.Total draft of 15m-16m is available and it is a natural choice for setting up transhipment hu...Cochin Port is an all-weather port situated within a protected natural harbour,just 11 km away from mainland shipping route.Total draft of 15m-16m is available and it is a natural choice for setting up transhipment hub.The International Container Transhipment Terminal(ICTT)at Vallarpadam was developed by DP World and M/s Cochin Port Trust(CPT).As a part of this project,the new Rail connectivity from ICTT at Vallarpadam to Idappalli station is 8.60km,including the construction of 4.62 km elevated bridge was awarded to AFCONS by M/s Rail Vikas Nigam Limited(RVNL),in 2007 with a scheduled completion by 2009.This bridge is constructed for single railway track and piling was done for the provision of a second railway track in future.The 4.62 km long bridge was successfully completed and Trial Loco run was done in March 2010.This paper includes details of sub-surface profile,engineering properties of soils,details of construction of pile foundations and Challenges faced during construction.展开更多
With the development of the major country diplomacy with Chinese characteristics,diplomatic discourse,as an important part of building China’s international discourse power,has attracted much attention.Personificatio...With the development of the major country diplomacy with Chinese characteristics,diplomatic discourse,as an important part of building China’s international discourse power,has attracted much attention.Personification is a common means in diplomatic discourse.By giving anthropomorphic expressions to countries,regions,institutions and policies,the purpose of building national identity and establishing national image can be achieved.Based on conceptual metaphor theory and national identity theory,this paper focuses on personification in diplomatic discourse with a case study of the regular press conference of Ministry of Foreign Affairs.It is found that the spokesperson skillfully constructed China’s positive national identity,such as peace-loving,openness and inclusiveness by using a large number of body metaphor,kinship metaphor and role metaphor.展开更多
Modernization,as a specific stage in the historical development of human society,possesses a multi-layered composite structure,with each layer playing both a promoting and inhibiting role in human development and dign...Modernization,as a specific stage in the historical development of human society,possesses a multi-layered composite structure,with each layer playing both a promoting and inhibiting role in human development and dignity simultaneously.Chinese modernization is a strategic choice made based on lessons learned from various experiences of modernization processes in other countries,reflecting judgments on the benefits and choices on the values of human development and dignity in modernization.It values the promotion of the free and well-rounded development of all individuals as its standard,demanding the full realization of the positive effects of modernization on human development and the overcoming of its negative effects.Human rights,aiming to promote the free and well-rounded development of every person as the ultimate value goal,are not only an intrinsic structural element of the modernization stage but also a social normative tool that restrains the direction of modernization development,aligning closely with the values pursued by Chinese modernization.Chinese modernization poses dual requirements for human rights protection:on the one hand,it demands the affirmation and promotion of the positive effects of modernization on human development and dignity through human rights standards,and on the other hand,it requires the prevention and mitigation of the negative effects of modernization on human development and dignity through human rights standards.There exists a certain tension between these two dimensions,necessitating an appropriate balance and thereby presenting corresponding requirements for China’s approach to human rights protection.展开更多
This paper describes and provides a critique of the design and implementation of the“scoops”-a set of bespoke multifunctioning architectural free-form elements that are a highlight of the new Soheil Abedian School o...This paper describes and provides a critique of the design and implementation of the“scoops”-a set of bespoke multifunctioning architectural free-form elements that are a highlight of the new Soheil Abedian School of Architecture at Bond University,Australia,by the office of Sir Peter Cook and Gavin Robotham,CRAB(Cook Robotham Architecture Bureau,London).The development includes the transfer of analogue design processes into digital 3d modeling,which is then analyzed and rationalized via an exchange with consultants and procurement contractors.The complexity of the concrete works necessitated the use of digital fabrication to make their implementation affordable and within time constraints,with said complexity creating a variety of challenges for many aspects of the entire delivery team.The 3d model played a critical role in communicating intent and accuracy at all stages.The use of site-based craftsmanship combined with computer aided design and fabrication overlapped to realize the project.展开更多
The target of integrated construction of comprehensive transportation hub is to integrate the traffic resources,achieve butt joint of pan-regional transportation mode,and finally realize the"seamless connection&q...The target of integrated construction of comprehensive transportation hub is to integrate the traffic resources,achieve butt joint of pan-regional transportation mode,and finally realize the"seamless connection"of the goods and"zero transfer"of the passenger traffic.Relying on the particularity of the geographical location and the convenience of the Yangtze River channel,Luzhou puts forth effort to build a comprehensive transport hub in Southern Sichuan and has made great efforts in traffic infrastructure construction.However,there are still some problems.Combining practice of Luzhou,using the advanced experience of foreign and domestic cities for reference,the paper pointed out that for the sake of constructing a comprehensive transportation hub,we need to build the traffic integration on the basis of the efficiency.Besides,the paper proposed the strategies for construction.展开更多
The construction industry, known for its low productivity, is increasingly utilising software and mobile apps to enhance efficiency. However, more comprehensive research is needed to understand the effectiveness of th...The construction industry, known for its low productivity, is increasingly utilising software and mobile apps to enhance efficiency. However, more comprehensive research is needed to understand the effectiveness of these technology applications. The PRISMA principles utilised a scoping review methodology to ascertain pertinent studies and extract significant findings. From 2013 onwards, articles containing data on mobile applications or software designed to enhance productivity in the construction sector were obtained from multiple databases, including Emerald Insight, Science Direct, IEEE Xplore, and Google Scholar. After evaluating 2604 articles, 30 were determined to be pertinent to the study and were subsequently analysed for the review. The review identified five key themes: effectiveness, benefits, successful implementation examples, obstacles and limitations, and a comprehensive list of software and mobile apps. In addition, 71 software and mobile apps have shown potentially how these technologies can improve communication, collaboration, project management, real-time collaboration, document management, and on-the-go project information and estimating processes in the construction industry, increasing efficiency and productivity. The findings highlight the potential of these technologies such as Automation, Radio-Frequency Identification (RFID), Building Information Modeling (BIM), Augmented Reality (AR), Virtual Reality (VR), and Internet of Things (IoT) to improve efficiency and communication in the construction industry. Despite challenges such as cost, lack of awareness, resistance to change, compatibility concerns, human resources, technological and security concerns and licensing issues, the study identifies specific mobile applications and software with the potential to enhance efficiency significantly, improve productivity and streamline workflows. The broader societal impacts of construction software and mobile app development include increased efficiency, job creation, and sustainability.展开更多
The issues of solvability and construction of a solution of the Fredholm integral equation of the first kind are considered. It is done by immersing the original problem into solving an extremal problem in Hilbert spa...The issues of solvability and construction of a solution of the Fredholm integral equation of the first kind are considered. It is done by immersing the original problem into solving an extremal problem in Hilbert space. Necessary and sufficient conditions for the existence of a solution are obtained. A method of constructing a solution of the Fredholm integral equation of the first kind is developed. A constructive theory of solvability and construction of a solution to a boundary value problem of a linear integrodifferential equation with a distributed delay in control, generated by the Fredholm integral equation of the first kind, has been created.展开更多
As the climate change signs become more noticeable, the concern to prioritize sustainability within the AEC industry intensifies. This particularly pertained to issues related to the demand of resources, the excessive...As the climate change signs become more noticeable, the concern to prioritize sustainability within the AEC industry intensifies. This particularly pertained to issues related to the demand of resources, the excessive consumption of raw materials, and the associated generated waste. Presently, the construction industry is ranked among the industries that are accountable for the global generation of solid waste and energy consumption, leading to detrimental environmental effects. Nonetheless, over the years, construction methods, technological innovations, and building practices have made considerable progress, influenced by a growing emphasis on sustainability, especially in energy conservation and in adopting the Industrialized Production layer of Construction 4.0 (i.e., modular prefabrication, 3D concrete printing, and BIM). The concept of Circular Economy (CE) has been identified as a potential solution to achieve sustainability in building construction through the design, construction, and end-of-life deconstruction processes that enhance the management of waste based on the framework that is related to reducing, reusing, and recycling. Moreover, information and data related to geolocation complement advanced digital technologies by providing a collaborative platform that supports the application of CE as a practical approach to sustainability. Thus, this study will provide a straightforward methodology for developing a model that integrates BIM and sustainable design with Circular Economy’s concept to enhance the sustainability of construction projects to minimize their waste based on various construction methods (i.e., conventional, modular, and 3D concrete printing). The proposed model interrelates tools and data for the evaluation and planning strategies for the construction and deconstruction waste (CDW) management at the design stage, including estimating the quantities of the wasted materials, quantifying the production rates of selected equipment for the waste handling (loading and hauling) at the various stages of a project as well their associated cost. The proposed model will help users to calculate the quantity of construction and deconstruction waste (CDW) during the design of buildings based on their different construction methods at the early stage by using the concept of Design for Deconstruction (DfD);sustainable construction methods;and deconstruction process for waste management, which will lead to the suitable construction method.展开更多
With the advent of Industry 4.0, smart construction sites have seen significant development in China. However, accidents involving digitized tower cranes continue to be a persistent issue. Among the contributing facto...With the advent of Industry 4.0, smart construction sites have seen significant development in China. However, accidents involving digitized tower cranes continue to be a persistent issue. Among the contributing factors, human unsafe behavior stands out as a primary cause for these incidents. This study aims to assess the human reliability of tower crane operations on smart construction sites. To proactively enhance safety measures, the research employs text mining techniques (TF-IDF-Truncated SVD-Complement NB) to identify patterns of human errors among tower crane operators. Building upon the SHEL model, the study categorizes behavioral factors affecting human reliability in the man-machine interface, leading to the establishment of the Performance Shaping Factors (PSFs) system. Furthermore, the research constructs an error impact indicator system for the intelligent construction site tower crane operator interface. Using the DEMATEL method, it analyzes the significance of various factors influencing human errors in tower crane operations. Additionally, the ISM-MICMAC method is applied to unveil the hierarchical relationships and driving-dependent connections among these influencing factors. The findings indicate that personal state, operating procedures, and physical environment directly impact human errors, while personal capability, technological environment, and one fundamental organizational management factor contribute indirectly. .展开更多
Lithium element has attracted remarkable attraction for energy storage devices, over the past 30 years. Lithium is a light element and exhibits the low atomic number 3, just after hydrogen and helium in the periodic t...Lithium element has attracted remarkable attraction for energy storage devices, over the past 30 years. Lithium is a light element and exhibits the low atomic number 3, just after hydrogen and helium in the periodic table. The lithium atom has a strong tendency to release one electron and constitute a positive charge, as Li<sup> </sup>. Initially, lithium metal was employed as a negative electrode, which released electrons. However, it was observed that its structure changed after the repetition of charge-discharge cycles. To remedy this, the cathode mainly consisted of layer metal oxide and olive, e.g., cobalt oxide, LiFePO<sub>4</sub>, etc., along with some contents of lithium, while the anode was assembled by graphite and silicon, etc. Moreover, the electrolyte was prepared using the lithium salt in a suitable solvent to attain a greater concentration of lithium ions. Owing to the lithium ions’ role, the battery’s name was mentioned as a lithium-ion battery. Herein, the presented work describes the working and operational mechanism of the lithium-ion battery. Further, the lithium-ion batteries’ general view and future prospects have also been elaborated.展开更多
文摘Automatic control technology is the basis of road robot improvement,according to the characteristics of construction equipment and functions,the research will be input type perception from positioning acquisition,real-world monitoring,the process will use RTK-GNSS positional perception technology,by projecting the left side of the earth from Gauss-Krueger projection method,and then carry out the Cartesian conversion based on the characteristics of drawing;steering control system is the core of the electric drive unmanned module,on the basis of the analysis of the composition of the steering system of unmanned engineering vehicles,the steering system key components such as direction,torque sensor,drive motor and other models are established,the joint simulation model of unmanned engineering vehicles is established,the steering controller is designed using the PID method,the simulation results show that the control method can meet the construction path demand for automatic steering.The path planning will first formulate the construction area with preset values and realize the steering angle correction during driving by PID algorithm,and never realize the construction-based path planning,and the results show that the method can control the straight path within the error of 10 cm and the curve error within 20 cm.With the collaboration of various modules,the automatic construction simulation results of this robot show that the design path and control method is effective.
基金Research on Zero Emission Campus Construction Based on Plant Community Optimization(Project number:KJQN202305605)。
文摘The development of the construction industry is shifting towards low-carbon construction,so it is necessary to improve and optimize related construction concepts,methods,and processes.By improving resource and energy control efficiency in building projects,minimizing construction waste,and reducing environmental impact,a foundation for the sustainable development of the industry can be established.This paper mainly analyzes the significance of low-carbon energy-saving construction technology and the control factors of construction,summarizes the status quo of the development of building energy-saving construction,and puts forward strategies for applying building energy-saving construction technology.These strategies serve to achieve low-carbon and energy-saving goals to promote the healthy development of energy-saving construction.
文摘Urbanization has led to the rapid development of the construction industry.However,this has also led to higher requirements for the construction engineering management.Other than the quality monitoring of engineering construction,the energy-saving properties of the building should also be considered.Therefore,a scientific management approach should be adopted to improve green building management.This paper primarily examines the importance of quality management in green building construction,along with the factors influencing it.It also identifies the quality issues present in current green building construction.Finally,it proposes measures for quality management in the green building construction process to facilitate the industry’s healthy development.
文摘In recent years,China has made significant progress in the construction of highways,resulting in an improved highway network that has provided robust support for economic and social development.However,the rapid expansion of highway construction,power supply,and distribution has led to several challenges in mechanical and electrical engineering technology.Ensuring the safe,stable,and cost-effective operation of the power supply and distribution system to meet the diverse requirements of highway operations has become a pressing issue.This article takes an example of a highway electromechanical engineering power supply and distribution construction project to provide insight into the construction process of highway electromechanical engineering power supply and distribution technology.
文摘As the urban populations grow,the number and size of subway construction projects are increasing while also meeting higher construction standards.So,subway construction projects must have a better understanding of construction technology.This article focuses on the construction technology of the subway tunnel expansion under the bridge foundation.By analyzing the engineering characteristics of the bridge foundation and using a project as an example,this article provides a detailed discussion of the construction process of tunnel expansion under a bridge foundation.This article aims to serve as a reference for subway tunnel construction in China to ensure the key points of construction technology are understood,thus improving construction quality and laying a solid technical foundation for the sustainable development of urban rail engineering.
基金supported by the National Natural Science Foundation of China(41871184)the National Social Science Fund of China(21ZDA056)the Scientific and Technological Innovation Project of the Chinese Academy of Agricultural Sciences(10-IAED-ZT-01-2023and 10-IAED-RC-07-2023)。
文摘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.
文摘Introduction: Work-related accidents are frequent and serious in the construction sector. The aim of the study was to determine the frequency and factors associated with occupational accidents on the construction site of a referral hospital in Benin. Methods: A cross-sectional study was carried out. The sample size was calculated using the Schwartz form adjusted for the number of workers on site and was 129 workers. Random sampling was used. The dependent variable was work-related accidents. The other variables were socio-demographic and occupational characteristics. Data were collected through a questionnaire survey. Medians and proportions were calculated. An association was sought using Chi-square and Fisher tests with a threshold of p Results: A total of 132 workers were included. Their median age was 30 years with an ITQ of [27 - 38];men were the most represented 126 (95.45%) with a level of education higher than or equal to high school in 101 (76.52%) and in the majority with a permanent status 85 (64.39%). Seniority of more than 5 years was observed in 92 (69.7%). Workers working more than 8 hours of overtime per week numbered 57 (43.18%). Exposure to vibrating objects was 49 (37.12%). In terms of psychosocial constraints, 82.58% had high psychological demands;79.53% low decision-making latitude;50.76% low social support. The frequency of work-related accidents was 6.82%, and the only associated factor was the type of worker (p = 0.016). On the other hand, there were 10.2% accidents among workers handling vibrating objects versus 4.98% among those not using them. With regard to psychosocial constraints, the following frequencies were recorded respectively: 6.42% among those with high psychological demand versus 8.7% among those with low psychological demand;7.62% among those with low decision-making latitude versus 3.7% among those with high decision-making latitude;8.96% among those with low social support versus 4.62% among those with high support. Conclusion: Work-related accidents on construction sites must be avoided by all possible means including the management of psychosocial constraints.
基金supported by a grant from the National Natural Science Foundations of China(No.52171282)supported by Taishan Scholars Program of Shandong Province,China(No.tsqn202306098)the Shandong Provincial Key Research and Development Plan,China(No.2021ZLGX04).
文摘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.
文摘Taking the changes of construction land in Wan’an County over the years as the research object,the quantity and spatial characteristics of construction land in Wan’an County were analyzed,and the overall situation and regional differences of construction land utilization in Wan’an County were revealed.From the aspects of main influencing factors such as land use structure,land use intensity,land input intensity and output benefit,an evaluation indicator system was established to evaluate the economical and intensive use level of construction land in Wan’an County.The results show that the score of the economical and intensive use level of construction land in Wan’an County was 56.92,which was the lowest among all the districts and counties in Ji’an City.Based on the evaluation results,the corresponding economizing and intensive strategies were put forward,and the safeguard measures for its implementation were explored.The purpose is to provide some support for the preparation of territorial spatial planning,the delineation of urban development boundaries,and the potential exploitation of construction land stock,hoping to improve the utilization efficiency and benefit of construction land in Wan’an County,and promote the economic growth of Wan’an County to the stage of high-quality development.
基金National Natural Science Foundation of China under Grand No.51808190the Central Government Guides Local Science and Technology Development Fund Projects under Grand No.XZ202301YD0019C+2 种基金the Foundation of Key Laboratory of Soft Soils and Geoenvironmental Engineering(Zhejiang University)Ministry of Education under Grand No.2022P04the Central University Basic Research Fund of China under Grand No.B220202017。
文摘This research is concentrated on the longitudinal vibration of a tapered pipe pile considering the vertical support of the surrounding soil and construction disturbance.First,the pile-soil system is partitioned into finite segments in the vertical direction and the Voigt model is applied to simulate the vertical support of the surrounding soil acting on the pile segment.The surrounding soil is divided into finite ring-shaped zones in the radial direction to consider the construction disturbance.Then,the shear complex stiffness at the pile-soil interface is derived by solving the dynamic equilibrium equation for the soil from the outermost to innermost zone.The displacement impedance at the top of an arbitrary pile segment is obtained by solving the dynamic equilibrium equation for the pile and is combined with the vertical support of the surrounding soil to derive the displacement impedance at the bottom of the upper adjacent segment.Further,the displacement impedance at the pile head is obtained based on the impedance function transfer technique.Finally,the reliability of the proposed solution is verified,followed by a sensitivity analysis concerning the coupling effect of the pile parameters,construction disturbance and the vertical support of the surrounding soil on the displacement impedance of the pile.
文摘Cochin Port is an all-weather port situated within a protected natural harbour,just 11 km away from mainland shipping route.Total draft of 15m-16m is available and it is a natural choice for setting up transhipment hub.The International Container Transhipment Terminal(ICTT)at Vallarpadam was developed by DP World and M/s Cochin Port Trust(CPT).As a part of this project,the new Rail connectivity from ICTT at Vallarpadam to Idappalli station is 8.60km,including the construction of 4.62 km elevated bridge was awarded to AFCONS by M/s Rail Vikas Nigam Limited(RVNL),in 2007 with a scheduled completion by 2009.This bridge is constructed for single railway track and piling was done for the provision of a second railway track in future.The 4.62 km long bridge was successfully completed and Trial Loco run was done in March 2010.This paper includes details of sub-surface profile,engineering properties of soils,details of construction of pile foundations and Challenges faced during construction.
文摘With the development of the major country diplomacy with Chinese characteristics,diplomatic discourse,as an important part of building China’s international discourse power,has attracted much attention.Personification is a common means in diplomatic discourse.By giving anthropomorphic expressions to countries,regions,institutions and policies,the purpose of building national identity and establishing national image can be achieved.Based on conceptual metaphor theory and national identity theory,this paper focuses on personification in diplomatic discourse with a case study of the regular press conference of Ministry of Foreign Affairs.It is found that the spokesperson skillfully constructed China’s positive national identity,such as peace-loving,openness and inclusiveness by using a large number of body metaphor,kinship metaphor and role metaphor.
基金a phased results of“Research on China’s Human Rights Practice Carrying Forward and Enriching the Common Values of All Humanity”(Project Approval Number 22ZDA127)a major project under the National Social Science Fund for expounding the spirit of the Sixth Plenary Session of the 19th Central Committee of the Communist Party of China。
文摘Modernization,as a specific stage in the historical development of human society,possesses a multi-layered composite structure,with each layer playing both a promoting and inhibiting role in human development and dignity simultaneously.Chinese modernization is a strategic choice made based on lessons learned from various experiences of modernization processes in other countries,reflecting judgments on the benefits and choices on the values of human development and dignity in modernization.It values the promotion of the free and well-rounded development of all individuals as its standard,demanding the full realization of the positive effects of modernization on human development and the overcoming of its negative effects.Human rights,aiming to promote the free and well-rounded development of every person as the ultimate value goal,are not only an intrinsic structural element of the modernization stage but also a social normative tool that restrains the direction of modernization development,aligning closely with the values pursued by Chinese modernization.Chinese modernization poses dual requirements for human rights protection:on the one hand,it demands the affirmation and promotion of the positive effects of modernization on human development and dignity through human rights standards,and on the other hand,it requires the prevention and mitigation of the negative effects of modernization on human development and dignity through human rights standards.There exists a certain tension between these two dimensions,necessitating an appropriate balance and thereby presenting corresponding requirements for China’s approach to human rights protection.
文摘This paper describes and provides a critique of the design and implementation of the“scoops”-a set of bespoke multifunctioning architectural free-form elements that are a highlight of the new Soheil Abedian School of Architecture at Bond University,Australia,by the office of Sir Peter Cook and Gavin Robotham,CRAB(Cook Robotham Architecture Bureau,London).The development includes the transfer of analogue design processes into digital 3d modeling,which is then analyzed and rationalized via an exchange with consultants and procurement contractors.The complexity of the concrete works necessitated the use of digital fabrication to make their implementation affordable and within time constraints,with said complexity creating a variety of challenges for many aspects of the entire delivery team.The 3d model played a critical role in communicating intent and accuracy at all stages.The use of site-based craftsmanship combined with computer aided design and fabrication overlapped to realize the project.
文摘The target of integrated construction of comprehensive transportation hub is to integrate the traffic resources,achieve butt joint of pan-regional transportation mode,and finally realize the"seamless connection"of the goods and"zero transfer"of the passenger traffic.Relying on the particularity of the geographical location and the convenience of the Yangtze River channel,Luzhou puts forth effort to build a comprehensive transport hub in Southern Sichuan and has made great efforts in traffic infrastructure construction.However,there are still some problems.Combining practice of Luzhou,using the advanced experience of foreign and domestic cities for reference,the paper pointed out that for the sake of constructing a comprehensive transportation hub,we need to build the traffic integration on the basis of the efficiency.Besides,the paper proposed the strategies for construction.
文摘The construction industry, known for its low productivity, is increasingly utilising software and mobile apps to enhance efficiency. However, more comprehensive research is needed to understand the effectiveness of these technology applications. The PRISMA principles utilised a scoping review methodology to ascertain pertinent studies and extract significant findings. From 2013 onwards, articles containing data on mobile applications or software designed to enhance productivity in the construction sector were obtained from multiple databases, including Emerald Insight, Science Direct, IEEE Xplore, and Google Scholar. After evaluating 2604 articles, 30 were determined to be pertinent to the study and were subsequently analysed for the review. The review identified five key themes: effectiveness, benefits, successful implementation examples, obstacles and limitations, and a comprehensive list of software and mobile apps. In addition, 71 software and mobile apps have shown potentially how these technologies can improve communication, collaboration, project management, real-time collaboration, document management, and on-the-go project information and estimating processes in the construction industry, increasing efficiency and productivity. The findings highlight the potential of these technologies such as Automation, Radio-Frequency Identification (RFID), Building Information Modeling (BIM), Augmented Reality (AR), Virtual Reality (VR), and Internet of Things (IoT) to improve efficiency and communication in the construction industry. Despite challenges such as cost, lack of awareness, resistance to change, compatibility concerns, human resources, technological and security concerns and licensing issues, the study identifies specific mobile applications and software with the potential to enhance efficiency significantly, improve productivity and streamline workflows. The broader societal impacts of construction software and mobile app development include increased efficiency, job creation, and sustainability.
文摘The issues of solvability and construction of a solution of the Fredholm integral equation of the first kind are considered. It is done by immersing the original problem into solving an extremal problem in Hilbert space. Necessary and sufficient conditions for the existence of a solution are obtained. A method of constructing a solution of the Fredholm integral equation of the first kind is developed. A constructive theory of solvability and construction of a solution to a boundary value problem of a linear integrodifferential equation with a distributed delay in control, generated by the Fredholm integral equation of the first kind, has been created.
文摘As the climate change signs become more noticeable, the concern to prioritize sustainability within the AEC industry intensifies. This particularly pertained to issues related to the demand of resources, the excessive consumption of raw materials, and the associated generated waste. Presently, the construction industry is ranked among the industries that are accountable for the global generation of solid waste and energy consumption, leading to detrimental environmental effects. Nonetheless, over the years, construction methods, technological innovations, and building practices have made considerable progress, influenced by a growing emphasis on sustainability, especially in energy conservation and in adopting the Industrialized Production layer of Construction 4.0 (i.e., modular prefabrication, 3D concrete printing, and BIM). The concept of Circular Economy (CE) has been identified as a potential solution to achieve sustainability in building construction through the design, construction, and end-of-life deconstruction processes that enhance the management of waste based on the framework that is related to reducing, reusing, and recycling. Moreover, information and data related to geolocation complement advanced digital technologies by providing a collaborative platform that supports the application of CE as a practical approach to sustainability. Thus, this study will provide a straightforward methodology for developing a model that integrates BIM and sustainable design with Circular Economy’s concept to enhance the sustainability of construction projects to minimize their waste based on various construction methods (i.e., conventional, modular, and 3D concrete printing). The proposed model interrelates tools and data for the evaluation and planning strategies for the construction and deconstruction waste (CDW) management at the design stage, including estimating the quantities of the wasted materials, quantifying the production rates of selected equipment for the waste handling (loading and hauling) at the various stages of a project as well their associated cost. The proposed model will help users to calculate the quantity of construction and deconstruction waste (CDW) during the design of buildings based on their different construction methods at the early stage by using the concept of Design for Deconstruction (DfD);sustainable construction methods;and deconstruction process for waste management, which will lead to the suitable construction method.
文摘With the advent of Industry 4.0, smart construction sites have seen significant development in China. However, accidents involving digitized tower cranes continue to be a persistent issue. Among the contributing factors, human unsafe behavior stands out as a primary cause for these incidents. This study aims to assess the human reliability of tower crane operations on smart construction sites. To proactively enhance safety measures, the research employs text mining techniques (TF-IDF-Truncated SVD-Complement NB) to identify patterns of human errors among tower crane operators. Building upon the SHEL model, the study categorizes behavioral factors affecting human reliability in the man-machine interface, leading to the establishment of the Performance Shaping Factors (PSFs) system. Furthermore, the research constructs an error impact indicator system for the intelligent construction site tower crane operator interface. Using the DEMATEL method, it analyzes the significance of various factors influencing human errors in tower crane operations. Additionally, the ISM-MICMAC method is applied to unveil the hierarchical relationships and driving-dependent connections among these influencing factors. The findings indicate that personal state, operating procedures, and physical environment directly impact human errors, while personal capability, technological environment, and one fundamental organizational management factor contribute indirectly. .
文摘Lithium element has attracted remarkable attraction for energy storage devices, over the past 30 years. Lithium is a light element and exhibits the low atomic number 3, just after hydrogen and helium in the periodic table. The lithium atom has a strong tendency to release one electron and constitute a positive charge, as Li<sup> </sup>. Initially, lithium metal was employed as a negative electrode, which released electrons. However, it was observed that its structure changed after the repetition of charge-discharge cycles. To remedy this, the cathode mainly consisted of layer metal oxide and olive, e.g., cobalt oxide, LiFePO<sub>4</sub>, etc., along with some contents of lithium, while the anode was assembled by graphite and silicon, etc. Moreover, the electrolyte was prepared using the lithium salt in a suitable solvent to attain a greater concentration of lithium ions. Owing to the lithium ions’ role, the battery’s name was mentioned as a lithium-ion battery. Herein, the presented work describes the working and operational mechanism of the lithium-ion battery. Further, the lithium-ion batteries’ general view and future prospects have also been elaborated.