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Comparing material wastage levels between conventional in-situ and prefabrication construction in Hong Kong
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作者 Vivian W YTam C M Tam L Y Shen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第5期548-551,共4页
Generation of construction wastes constitutes a major impact to the environment. Studies have been directed toward reducing wastes of the various construction processes. However, contractors in Hong Kong are rather co... Generation of construction wastes constitutes a major impact to the environment. Studies have been directed toward reducing wastes of the various construction processes. However, contractors in Hong Kong are rather conservative and lack motivation to develop new technology for waste minimization. This paper examines the benefits of using prefabrication in reducing material wastage levels for some traditional in-situ trades such as concreting, rebar fixing, bricklaying, drywall, plastering, screeding and tiling in Hong Kong. By measuring thirty construction projects, it is been found that waste levels of all major construction trades can be effectively reduced. This is particularly significant in the trade of plastering where 100% saving can be achieved after adopting prefabrication. The standardized design of the building can also be useful in the adoption of prefabrication for private housing projects. 展开更多
关键词 prefabrication conventional in-situ trades material wastage environment
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Application of Prefabrication and Assembly to Hong Kong-Zhuhai- Macao Bridge
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作者 Huaying Lu 《Frontiers Research of Architecture and Engineering》 2020年第2期6-12,共7页
The Hong Kong-Zhuhai-Macao Bridge(HZMB)project,which has just been opened to traffic in 2018.The special location,construction conditions,quality requirements and multiple functions of HZMB brought many challenges,suc... The Hong Kong-Zhuhai-Macao Bridge(HZMB)project,which has just been opened to traffic in 2018.The special location,construction conditions,quality requirements and multiple functions of HZMB brought many challenges,such as management,technology,safety and environmental protection.To meet these challenges and ensure the achievement of high quality and 120 years design service life,the HZMB project first introduced the completely new concept of"Large size,Factory production,Standardization and Assembly",which was fundamental to the design and construction.This was developed in consideration of the difficulties of the offshore environment.The core idea was Prefabrication and Assembly,which was to change this HZMB project into onshore work as much as possible by cutting this mega sea-crossing into large sized components,which could be prefabricated on land and then transported to the offshore site for assembly.The success of the HZMB undoubtedly has led the technology of prefabrication and assembly to a new height and recognized scale.This paper describes the implementation process of the concept;"Large size,Factory production,Standardization and Assembly"(LFSA)to the HZMB. 展开更多
关键词 Mega project prefabrication ASSEMBLY Technology Construction concept
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Prefabricated Construction of Reinforced Concrete Frame Structure with High Prefabrication Rate
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作者 LOU Taoqun 《外文科技期刊数据库(文摘版)工程技术》 2021年第6期304-308,共9页
In this paper, the structural form of the project is frame structure, and the prefabrication rate is 80%. The main structures such as column, beam, laminated plate, balcony plate, toilet plate, exterior wall plate, gu... In this paper, the structural form of the project is frame structure, and the prefabrication rate is 80%. The main structures such as column, beam, laminated plate, balcony plate, toilet plate, exterior wall plate, gutter and parapet and so on are prefabricated components. According to the construction organization process of the project, the construction process of the assembled integral concrete frame structure is discussed. Firstly, the key preparation work in the early stage of prefabricated construction site is analyzed from three aspects: construction flow section division, component yard layout and component delivery plan. Secondly, the paper analyzes the construction organization process of the project, focusing on the interpenetration of construction processes. Finally, considering the key construction procedures and main influencing factors, the construction methods and solutions are put forward and applied to improve the adjustment of column reserved reinforcement, vertical grouting connection of precast column, supporting mode of external retaining wall of frame structure, hoisting mode of high prefabricated component and special planning of prefabricated construction with BIM Technology. For the next step in-depth study of the prefabricated construction technology and provide the basis for guiding the prefabricated construction of frame structure. 展开更多
关键词 high prefabrication rate frame structure assembly construction BIM technology application
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Research on the bearing capacity characteristics of initial support for horseshoe-shaped tunnel prefabrication
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作者 Yongtao Xue Fayuan Yan +3 位作者 Chengzhi Qi Haochen Zhang Zhao Xiuwang Chen Jingxu 《Deep Underground Science and Engineering》 2024年第4期426-438,共13页
In view of the limited theoretical research on the load model of initial support for horseshoe-shaped prefabrication,this study focuses on the Luochuan Tunnel on the Xi'an-Yan'an newly built railway as the res... In view of the limited theoretical research on the load model of initial support for horseshoe-shaped prefabrication,this study focuses on the Luochuan Tunnel on the Xi'an-Yan'an newly built railway as the research object to explore its load model,load characteristic curve,plastic zone,deformation,and critical thickness.Theoretical research and numerical analysis were conducted.The results indicate that under the same boundary conditions,the ultimate bearing capacity of the prefabricated assembly initial support is higher than that of the shotcrete initial support,resulting in larger ultimate deformation capacity of the prefabricated assembly initial support.Based on numerical calculations,the ultimate deformation and critical thickness of the prefabricated initial lining for single-and double-track railway tunnels are obtained when buried at depths of 200,500,and 900 m in rock masses of classes Ⅲ,Ⅳ,and Ⅴ. 展开更多
关键词 critical thickness load model numerical analysis prefabricated assembly initial support ultimate bearing capacity
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An integrated review of automation and robotic technologies for structural prefabrication and construction 被引量:2
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作者 Cheav Por Chea Yu Bai +2 位作者 Xuebei Pan Mehrdad Arashpour Yunpeng Xie 《Transportation Safety and Environment》 EI 2020年第2期81-96,共16页
Building construction has developed from the use of primitive tools to that of machinery,with a tendency toward automation.Automation of processes and robotics can improve efficiency,accuracy and safety in constructio... Building construction has developed from the use of primitive tools to that of machinery,with a tendency toward automation.Automation of processes and robotics can improve efficiency,accuracy and safety in construction.On the other hand,structural prefabrication for construction is increasingly being adopted worldwide to enhance productivity and to alleviate the environmental impact of conventional construction processes.The combination and application of automation and prefabrication technologies may therefore introduce new developments to the construction industry.This paper provides a comprehensive review of the use of automation technology for structural prefabrication and construction,including recent developments,challenges and future trends.Five stages following the sequence of construction are proposed:design,construction management,robotic manufacturing,autonomous transportation and automatic structural assembly.The paper concludes that the widespread use of automation technology is preferable to structural prefabrication for construction,and that the design for robotic construction introduced through connection innovations may be beneficial as a means of avoiding complex operations and thus improving the efficiency of robotic assembly processes. 展开更多
关键词 prefabrication autonomous transport system robotic construction construction automation building information modelling(BIM)
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Energy and Buildings
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《建筑节能(中英文)》 2025年第12期20-20,共1页
https://www.sciencedirect.com/journal/energy-and-buildings/vol/348/suppl/C Volume 348,1 December 2025[OA](1)Active prefabricated façade with building-integrated photovoltaic(APF-BIPV)technologies for high energy ... https://www.sciencedirect.com/journal/energy-and-buildings/vol/348/suppl/C Volume 348,1 December 2025[OA](1)Active prefabricated façade with building-integrated photovoltaic(APF-BIPV)technologies for high energy efficient building renovation:a systematic review of recent research advancements by Graziano Salvalai,Feiyu Zhao,Article 116440 Abstract:Active Prefabricated Fa ade with building-integrated photovoltaic(APF-BIPV)technologies used in the prefabricated building envelope component offer a promising approach to energy-efficient building renovation,combining renewable energy generation with modular construction advantages.This study systematically reviews APF-BIPV technologies,assessing their technological development,performance optimization,economic feasibility,and policy implications.Based on PRISMA methodology,the review includes not only peer-reviewed publications from Scopus and Web of Science but also analyzes research outputs from European-funded projects,highlighting the significant technological advancements that have transformed prefabricated fa ade components from basic cladding systems into highly integrated,multifunctional building elements,integrating PV technology for renewable energy production. 展开更多
关键词 prefabricated fa ade active prefabricated facade technological development economic feasibility prefabricated building envelope component building integrated photovoltaic APF BIPV energy efficient building renovation
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Characterization of combined blast-and fragments-induced synergetic damage in polyurea coated liquid-filled container
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作者 Chen Tao Chong Ji +3 位作者 Xin Wang Juan Gu Yuting Wang Changxiao Zhao 《Defence Technology(防务技术)》 2025年第1期201-224,共24页
Liquid-filled containers(LFC)are widely used to store and transport petroleum,chemical reagents,and other resources.As an important target of military strikes and terrorist bombings,LFC are vulnerable to blast waves a... Liquid-filled containers(LFC)are widely used to store and transport petroleum,chemical reagents,and other resources.As an important target of military strikes and terrorist bombings,LFC are vulnerable to blast waves and fragments.To explore the protective effect of polyurea elastomer on LFC,the damage characteristics of polyurea coated liquid-filled container(PLFC)under the combined loading of blast shock wave and fragments were studied experimentally.The microstructure of the polyurea layer was observed by scanning electron microscopy,and the fracture and self-healing phenomena were analyzed.The simulation approach was used to explain the combined blast-and fragments-induced on the PLFC in detail.Finally,the effects of shock wave and fragment alone and in combination on the damage of PLFC were comprehensively compared.Results showed that the polyurea reduces the perforation rate of the fragment to the LFC,and the self-healing phenomenon could also reduce the liquid loss rate inside the container.The polyurea reduces the degree of depression in the center of the LFC,resulting in a decrease in the distance between adjacent fragments penetrating the LFC,and an increase in the probability of transfixion and fracture between holes.Under the close-in blast,the detonation shock wave reached the LFC before the fragment.Polyurea does not all have an enhanced effect on the protection of LFC.The presence of internal water enhances the anti-blast performance of the container,and the hydrodynamic ram(HRAM)formed by the fragment impacting the water aggravated the plastic deformation of the container.The combined action has an enhancement effect on the deformation of the LFC.The depth of the container depression was 27%higher than that of the blast shock wave alone;thus,it cannot be simply summarized as linear superposition. 展开更多
关键词 POLYUREA Prefabricated fragment Liquid-filled container Hydrodynamic ram Cumulative effect
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Review of the Research on the Impact Resistance Mechanical Performance of Prestressed Segmental Precast and Assembled Piers
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作者 Chengquan Wang Rongyang Liu +4 位作者 Xinquan Wang Boyan Ping Haimin Qian Xiao Li Yuhan Liang 《Structural Durability & Health Monitoring》 2025年第4期819-850,共32页
This article provides an overview of the current development status of prestressed segmental precast and assembled piers,Emphasis was placed on analyzing the stress characteristics of bridge piers under impact.The con... This article provides an overview of the current development status of prestressed segmental precast and assembled piers,Emphasis was placed on analyzing the stress characteristics of bridge piers under impact.The concept of recoverable functional design and its application prospects were elaborated,and finally,the research on the impact resistance performance of prestressed segmental precast and assembled pierswas discussed.Research has shown that optimizing design and material selection can effectively enhance the impact resistance and structural durability of bridge piers.At the same time,the introduction of the concept of recoverable functionality provides new ideas for the rapid repair and functional recovery of bridge piers,which helps to improve the recovery efficiency of bridges after extreme events.Future research should focus on the evaluation methods of impact resistance performance,new connection technologies,in-depth application of recoverable functional design,a combination of impact simulation experiments and numerical analysis,and exploration of comprehensive disaster prevention and reduction strategies.These research results will also promote the further development and innovation of prefabricated assembly technology in bridge engineering,bringing new ideas and methods to the field of engineering construction. 展开更多
关键词 Prefabricated assembly bridge piers impact resistance performance restorable function
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A Framework of Information Sharing Platform for Prefabricated Building Supply Chain Based on BIM
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作者 Min Zhang Yanxiao Bian 《Journal of World Architecture》 2025年第4期15-27,共13页
In view of the imperfect supply chain management of prefabricated building,inadequate information interaction among the participating subjects,and untimely information updates,the integration and development of BIM te... In view of the imperfect supply chain management of prefabricated building,inadequate information interaction among the participating subjects,and untimely information updates,the integration and development of BIM technology plus the supply chain of prefabricated building is analyzed,and the problems existing in the current supply chain and the application of BIM technology at various stages are elaborated.By analyzing the structural composition of the prefabricated building supply chain,an information sharing platform framework for prefabricated building supply chain based on BIM was established,which serves as a valuable reference for managing prefabricated building supply chains.BIM technology aligns well with assembly construction,laying a solid foundation for their synergistic development and offering novel research avenues for the prefabricated building supply chain. 展开更多
关键词 BIM technology Supply chain management Prefabricated building Information flow
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Research on Modular Design,Production,and Construction Integration of Municipal Prefabricated Bathroom Stations
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作者 Qiang Huang 《Journal of Architectural Research and Development》 2025年第5期57-62,共6页
This article focuses on the municipal prefabricated bathroom station.It elaborates on its modular design concept,including key design points such as spatial layout,functional modules,and determination of key parameter... This article focuses on the municipal prefabricated bathroom station.It elaborates on its modular design concept,including key design points such as spatial layout,functional modules,and determination of key parameters;introduces the optimization of intelligent production processes,precision control,and integration of construction technology,and also mentions the verification of full lifecycle applications and quality control;as well as emphasizes the importance of BIM+IoT platform and looks forward to the future. 展开更多
关键词 Municipal prefabricated Bathroom station Modular design
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Seismic behavior of prefabricated,assembled,self-centering bridge piers with a damage transfer configuration
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作者 Zhang Juhui Wu Jiashun +1 位作者 Qian Yiqing Guan Zhongguo 《Earthquake Engineering and Engineering Vibration》 2025年第3期861-874,共14页
To address local concrete damage in joint areas at the footing of prefabricated assembled self-centering bridge piers(PASPs)in seismic design,a damage transfer configuration(DTC)was proposed,based on the bridge pier s... To address local concrete damage in joint areas at the footing of prefabricated assembled self-centering bridge piers(PASPs)in seismic design,a damage transfer configuration(DTC)was proposed,based on the bridge pier structure configuration and the mechanism of local damage formation.Integrating the DTC into the PASP,numerical models of a previous experimental reference PASP and a PASP with damage transfer configuration(DTPASP)were established using the finite element software ABAQUS with a concrete damage plasticity(CDP)model.The models were then compared with experimental results regarding damage distribution,hysteresis curves,energy dissipation capacity,the joint opening degree,and residual displacement.The findings indicate that the finite element model developed in this study can well reflect the experimental results of the reference PASP.The incorporation of the DTC proved to be beneficial in preserving structural integrity,bearing capacity,and the functionality of the core structure of bridge piers following an earthquake.Meanwhile,this addition did not exert a significant influence on the seismic behavior of the core structure of the bridge pier. 展开更多
关键词 bridge engineering seismic behavior numerical models prefabricated assembled self-centering bridge piers damage transfer configuration
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Overview of Prefabricated Segmental Pier Column Connection Technology
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作者 MaoGuang Yue Pan Huang 《Journal of Environmental & Earth Sciences》 2025年第4期309-323,共15页
With the acceleration of urbanization,prefabricated bridges have become a significant choice for transportation infrastructure construction due to their environmental friendliness,efficiency,and reliable quality.Howev... With the acceleration of urbanization,prefabricated bridges have become a significant choice for transportation infrastructure construction due to their environmental friendliness,efficiency,and reliable quality.However,existing connection technologies still face shortcomings in construction efficiency,seismic performance,and cost control.This paper summarizes the process characteristics of commonly used connection technologies such as socket connections,grouted sleeve connections and corrugated pipe connections,and analyzes their seismic capacity and mechanical performance.In response to existing issues,two new technologies—separated steel connection and multi-chamber steel tube concrete connection—are proposed,and their comprehensive performance and economic efficiency are analyzed.The new connection technologies outperform traditional methods in construction efficiency,economic efficiency,and structural stability,with more reasonable force distribution,clearer load transfer paths,and significantly reduced overall costs.Existing technologies,such as socket connections,perform well in seismic performance but are complex to construct;grouted sleeve connections are mature in technology,but the quality of grouting is difficult to inspect.The separated steel connection and multi-chamber steel tube concrete connection technologies offer significant advantages.With the increasing demands for energy conservation and emission reduction,coupled with the rising labor costs,prefabricated bridge piers are undoubtedly poised to become one of the preferred technologies for bridge construction in China in the future.Therefore,in light of the current research landscape,this paper concludes by offering a forward-looking perspective on the development directions of connection methods for prefabricated bridge piers and identifying key areas for future research. 展开更多
关键词 Prefabricated Bridges Construction Efficiency Structural Stability Separated Steel Connection Multi-Chamber Steel Tube Concrete Connection
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Study on seismic and thermal performance of prefabricated composite wall based on fiber-reinforced EPS concrete
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作者 LUO Bin WANG Bin +2 位作者 SONG Yechao TANG Zhonghua DU Tingting 《Journal of Southeast University(English Edition)》 2025年第4期501-511,共11页
To integrate insulation and load-bearing functions in prefabricated composite wall structures,a novel design based on fiber-reinforced expanded polystyrene(EPS)con-crete is proposed.The research focuses on three key a... To integrate insulation and load-bearing functions in prefabricated composite wall structures,a novel design based on fiber-reinforced expanded polystyrene(EPS)con-crete is proposed.The research focuses on three key as-pects:material properties,seismic performance,and ther-mal performance.Firstly,the compressive strength and thermal conductivity of fiber-reinforced EPS concrete were analyzed at different sand ratios,leading to the development of an optimal mix design and a damage constitutive model.Secondly,a combination of experimental and numerical analysis methods was used to investigate the seismic perfor-mance of prefabricated composite walls with different infill materials,including autoclaved aerated fly ash and fiber-reinforced EPS concrete.Finally,thermal perfor-mance studies were conducted on prefabricated composite wall panels with different infill materials.The results indi-cate that the specimens underwent elastic,elastoplastic,and failure stages during loading.While specimens using EPS concrete exhibited a slightly lower overall bearing capacity,they demonstrated superior ductility,energy dissipation ca-pacity,and enhanced insulation and thermal stability. 展开更多
关键词 expanded polystyrene(EPS)concrete sand ra-tio prefabricated composite wall low-cycle reversed load-ing test seismic performance thermal performance
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Construction of a Green Evaluation System for Prefabricated Buildings Based on BIM Technology from the Perspective of Carbon Footprint
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作者 Lingfang Li 《Journal of World Architecture》 2025年第5期75-81,共7页
Driven by the goal of carbon neutrality,prefabricated buildings,as an important form of green construction,have become a key focus in the study of lifecycle carbon footprint management.Based on this,this paper starts ... Driven by the goal of carbon neutrality,prefabricated buildings,as an important form of green construction,have become a key focus in the study of lifecycle carbon footprint management.Based on this,this paper starts from the perspective of carbon footprint and combines the digital and visual advantages of BIM technology to construct a green evaluation system for prefabricated buildings.It explores the carbon emissions in each stage of the building and proposes corresponding improvement measures,aiming to provide necessary references for the low-carbon transformation of prefabricated buildings. 展开更多
关键词 Carbon footprint perspective BIM technology Prefabricated buildings
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Tubularized urethral reconstruction using a prevascularized capsular tissue prelaminated with buccal mucosa graft in a rabbit model 被引量:1
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作者 Hai-Lin Guo Zhi-Ming Jia +6 位作者 Lin Wang Xing-Qi Bao Yi-Chen Huang Jun-Mei Zhou Hua Xie Xiu-Jun Yang Fang Chen 《Asian Journal of Andrology》 SCIE CAS CSCD 2019年第4期381-386,共6页
Tubularized graft urethroplasty fails largely because of in adequate graft take. Prefabricati on of buccal mucosa lined flap has theoretical in dications for con structi ng neourethra with an in depe ndent blood suppl... Tubularized graft urethroplasty fails largely because of in adequate graft take. Prefabricati on of buccal mucosa lined flap has theoretical in dications for con structi ng neourethra with an in depe ndent blood supply. The efficacy of using a tissue expander capsule as an in duced vascular bed to prefabricate an axial vascularized buccal mucosa-lined flap for tubularized urethral rec on struction in a rabbit model was tested. The experiments were performed in three stages. First, silicone tissue expanders were inserted into the groin to induce vascularized capsule pouch formation. Next, buccal mucosa grafts were transplanted to the newly formed capsular tissue supplied by the axial vessel for buccal mucosa-lined flap prefabrication. Then, circumferential urethral defects were created and repaired by buccal mucosa graft (Group 1), capsule flap (Group 2) and prefabricated capsule buccal mucosa composite flap (Group 3). With retrograde urethrography, no rabbits in Group 1 maintained a wide urethral caliber. In Group 2, the discontinued epithelial layer rege nerated at 1 month, and the con structed n eourethra narrowed eve n though the lume n surface formed in tact urothelial cells at 3 months. In Group 3, buccal mucosa formed the lining in the neourethra and kept a wide urethral caliber for 3 mon ths. The capsule may serve as an in duced vascular bed for buccal mucosa-li ned flap prefabricati on. The prefabricated buccal mucosa-lined flap may serve as a neourethra flap for circumferential urethral replacement. 展开更多
关键词 BUCCAL MUCOSA flap prefabrication URETHRA VASCULARIZATION
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SECCL-based research on prefabricated chunks in achieving oral English fluency
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作者 刘春阳 杨雨时 《Sino-US English Teaching》 2010年第11期16-21,共6页
Fluency on oral English has always been the goal of Chinese English learners. Language corpuses offer great convenience to language researches. Prefabricated chunks are a great help for learners to achieve oral Englis... Fluency on oral English has always been the goal of Chinese English learners. Language corpuses offer great convenience to language researches. Prefabricated chunks are a great help for learners to achieve oral English fluency. With the help of computer software, chunks in SECCL are categorized. The conclusion is in the process of chunks acquiring, emphasis should be on content-related chunks, especially specific topic-related ones. One effective way to gain topic-related chunks is to build topic-related English corpus of native speakers. 展开更多
关键词 oral English fluency prefabricated chunks English corpus content-related chunks specific topic-related chunks
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Tissue expander capsule as an induced vascular bed to prefabricate an axial vascularized buccal mucosa-lined flap for tubularized posterior urethral reconstruction: preliminary results in an animal model
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作者 Hai-Lin Guo Lin Wang +6 位作者 Zhi-Ming Jia Xing-Qi Bao Yi-Chen Huang Jun-Mei Zhou Hua Xie Xiu-Jun Yang Fang Chen 《Asian Journal of Andrology》 SCIE CAS CSCD 2020年第5期459-464,共6页
Surgical repair of complex posterior urethral disruptions remains one of the most challenging problems in urology.The efficacy of using a tissue expander capsule as an induced vascular bed to prefabricate axial vascul... Surgical repair of complex posterior urethral disruptions remains one of the most challenging problems in urology.The efficacy of using a tissue expander capsule as an induced vascular bed to prefabricate axial vascularized buccal mucosa-lined flaps for tubularized posterior urethral reconstruction in a rabbit model was tested.The experiments were performed in three stages.First,silicone tissue expanders were inserted into the groin to induce vascularized capsule pouch formation.Next,buccal mucosa grafts were transplanted into the newly formed capsular tissue supplied by axial vessels for buccal mucosa-lined flap prefabrication.Then,circumferential posterior urethral defects were created and repaired with the buccal mucosa graft(Group 1),the capsule flap(Group 2),and the prefabricated capsule buccal mucosa composite flap(Group 3).After surgery,notable contracture of the tubularized buccal mucosa graft was observed in the neourethra,and none of the rabbits in Group 1 maintained a wide urethral caliber.In Group 2,the retrieved neourethra showed little evidence of epithelial lining during the study period,and the lumen caliber was narrowed at the 3-month evaluation.In Group 3,the buccal mucosa formed the lining in the neourethra and maintained a wide urethral caliber for 3 months.The capsule may serve as an induced vascular bed for buccal mucosa-lined flap prefabrication.The prefabricated buccal mucosa-lined flap may serve as a neourethra flap for posterior urethral replacement. 展开更多
关键词 buccal mucosa FLAP prefabrication URETHRA VASCULARIZATION
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STRESS FIELD AT A TIP OF A PREFABRICATED SPIRAL V-NOTCH
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作者 郑周练 陈山林 叶晓明 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第6期612-617,共6页
Based on the tranditional V-notched blasting, a technique of spirally V-notched blasting to loosen earth and rock was presented. Fracture mechanics and Westergaard stress function were adopted to build a complex stres... Based on the tranditional V-notched blasting, a technique of spirally V-notched blasting to loosen earth and rock was presented. Fracture mechanics and Westergaard stress function were adopted to build a complex stress function to derive the plane stress and strain fields at one tip of the crack under a quasi-static pressure. An expression was formulated to define the stress intensity factor of spiral V-notch loosen blasting. Factors that have effects on the stress intensity factor were studied. It is demonstrated that spiral V-notch loosen blasting is an extension of vertical V-notch blasting, straight cracking, and alike theories. 展开更多
关键词 prefabrication spiral notch stress field stress intensity factor quasi-static pressure
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Offsite Manufacturing: A Survey on the Current Status and Risks of Offsite Construction in Iran
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作者 Arman Hashemi 《Journal of Civil Engineering and Architecture》 2015年第2期141-152,共12页
Iran needs around 1.5 million residential homes to be constructed annually to answer its cumulative demand by 2025. Given the current situation of the Iranian construction industry, it seems almost impossible to achie... Iran needs around 1.5 million residential homes to be constructed annually to answer its cumulative demand by 2025. Given the current situation of the Iranian construction industry, it seems almost impossible to achieve this objective by using traditional methods of construction alone. Offsite manufacturing (OSM) can potentially increase the housing output in Iran thanks to its advantages over traditional methods of construction. However, OSM imposes a different set of risks which should be studied in the Iranian context. This study aims to investigate the readiness of the Iranian construction industry if offsite methods were to be introduced to the country in large industrial scales. To this end, a questionnaire survey was conducted to identify the risks and required actions in order to achieve successful application of these methods. Several subjects including costs, practicality, design and construction processes, demand, governmental policies, technology, and sustainability issues were investigated as the core research areas. The results revealed that, considering the current situations, it would be highly risky to introduce offsite methods of construction to Iran. Research findings highlight some key areas including design and construction processes, economies of scale, governmental supports, and education, which should be addressed to mitigate the identified risks. 展开更多
关键词 Offsite construction offsite manufacturing prefabrication construction technology HOUSING Iranian construction industry.
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Study on EFL and Prefabricated Chunks
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作者 杨春宇 《海外英语》 2021年第5期272-273,共2页
Language is the most important tool for human beings with the outside world.In order to improve the efficiency of communication,people need to maximize the efficiency of language processing to ensure the smooth produc... Language is the most important tool for human beings with the outside world.In order to improve the efficiency of communication,people need to maximize the efficiency of language processing to ensure the smooth production and understanding of the meaning,although it is a subtle and complex process in human communication.As Dr.Widdowson proposed that language knowledge is largely chunk knowledge in the 1980’s.The process of language output is the process of copying prefabricated Chunks knowledge and then transferring it to language output.Based on data collected before,this paper intends to study the dominant reproduction and implicit output of the English language from the perspective of prefabricated chunks,to play a guiding role in optimizing the output ability of EFL learners. 展开更多
关键词 Prefabricated chunks features of chunk use EFL learners INPUT OUTPUT
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