As Internet becomes largely used in the AEC (architecture, engineering andconstruction) industry, the main focus is in the area of information and project management. In thedynamic engineering consulting, less has bee...As Internet becomes largely used in the AEC (architecture, engineering andconstruction) industry, the main focus is in the area of information and project management. In thedynamic engineering consulting, less has been done so far. This research tries to find thepossibility and potential of the Internet application in design and consulting for the AEC industryby proposing a working model in specific area, steel construction. Several issues have beendiscussed: defining and formatting the typical procedure and character of the steel constructionconsulting, behavior approach based on activities among partners, and the model organization.展开更多
In the light of the theory of constructivism, the interactive web-based college English teaching model is intended to facilitate "autonomy", "inquiry" and "cooperation" in learning English. This paper presents a...In the light of the theory of constructivism, the interactive web-based college English teaching model is intended to facilitate "autonomy", "inquiry" and "cooperation" in learning English. This paper presents a research in which the interactive web-based college English teaching model intends to reshape the teacher's and learner's roles in the classroom. Based on the research, an exploration is made --- within the framework of the interactive web-based model --- on the design of "teaching model" and "learning model", its application and related potential problems.展开更多
The study on the earthquake-resistant performance of a pile-soil-structure interaction system is a relatively complicated and primarily important issue in civil engineering practice. In this paper, a computational mod...The study on the earthquake-resistant performance of a pile-soil-structure interaction system is a relatively complicated and primarily important issue in civil engineering practice. In this paper, a computational model and computation procedures for pile-supported structures, which can duly consider the pile-soil interaction effect, arc established by the finite clement method. Numerical implementation is made in the time domain. A simplified approximation for the seismic response analysis of pile-soil-structure systems is briefly presented. Then a comparative study is performed for an engineering example with numerical results computed respectively by the finite clement method and the simplified method. Through comparative analysis, it is shown that the results obtained by the simplified method well agree with those achieved by the finite element method. The numerical results and findings will offer instructive guidelines for earthquake-resistant analysis and design of pile-supported structures.展开更多
Aims Ecosystem engineers substantially modify the environment via their impact on abiotic conditions and the biota,resulting in facilitation of associated species that would not otherwise grow.Yet,reciprocal effects a...Aims Ecosystem engineers substantially modify the environment via their impact on abiotic conditions and the biota,resulting in facilitation of associated species that would not otherwise grow.Yet,reciprocal effects are poorly understood as studies of plant–plant interactions usually estimate only benefits for associated species,while how another trophic level may mediate direct and indirect feedback effects for ecosystem engineers is hardly considered.Methods We ran a field experiment with two ecosystem engineers(Arenaria tetraquetra and Hormathophylla spinosa)blooming either alone or with associated plants to decompose net effects and to test the hypothesis that pollinator-mediated interactions provide benefits that balance costs of facilitation by ecosystem engineers.Important Findings We found that net costs of facilitation are accompanied by pollinator-mediated benefits.Despite ecosystem engineers producing fewer flowers per plant,they were visited by more and more diverse pollinators per flower when blooming with associated plants than when blooming alone.Although seed production per plant was higher when ecosystem engineers bloomed alone,fruit set and seed set varied between species.In one case(A.tetraquetra),fruit and seed sets were negatively affected by the presence of associated plants,whereas,in another case(H.spinosa),fruit set and seed set were higher and unaffected when ecosystem engineers bloomed with associated plants,respectively.Our findings suggest that besides experiencing direct costs,ecosystem engineers can also benefit from facilitating other species via increasing their own visibility to pollinators.Thus,we highlight that pollination interactions can compensate for costs of facilitation depending on ecosystem engineer species.This study illuminates how the outcome of direct plant–plant interactions might be mediated by indirect interactions including third players.展开更多
Across-wind loads and effects have become increasingly important factors in the structural design of super-tall buildings and structures with increasing height. Across-wind loads and effects of tall buildings and stru...Across-wind loads and effects have become increasingly important factors in the structural design of super-tall buildings and structures with increasing height. Across-wind loads and effects of tall buildings and structures are believed to be excited by inflow turbulence, wake, and inflow-structure interaction, which are very complicated. Although researchers have been focusing on the problem for over 30 years, the database of across-wind loads and effects and the computation methods of equivalent static wind loads have not yet been developed, most countries having no related rules in the load codes. Research results on the across-wind effects of tall buildings and structures mainly involve the determination of across-wind aerodynamic forces and across-wind aerodynamic damping, development of their databases, theoretical methods of equivalent static wind loads, and so on. In this paper we first review the current research on across-wind loads and effects of super-tall buildings and structures both at home and abroad. Then we present the results of our study. Finally, we illustrate a case study in which our research results are applied to a typical super-tall structure.展开更多
文摘As Internet becomes largely used in the AEC (architecture, engineering andconstruction) industry, the main focus is in the area of information and project management. In thedynamic engineering consulting, less has been done so far. This research tries to find thepossibility and potential of the Internet application in design and consulting for the AEC industryby proposing a working model in specific area, steel construction. Several issues have beendiscussed: defining and formatting the typical procedure and character of the steel constructionconsulting, behavior approach based on activities among partners, and the model organization.
文摘In the light of the theory of constructivism, the interactive web-based college English teaching model is intended to facilitate "autonomy", "inquiry" and "cooperation" in learning English. This paper presents a research in which the interactive web-based college English teaching model intends to reshape the teacher's and learner's roles in the classroom. Based on the research, an exploration is made --- within the framework of the interactive web-based model --- on the design of "teaching model" and "learning model", its application and related potential problems.
基金supported by the National Natural Science Foundation of China(No.50179006)Science Development Foundation of Shandong University of Science and Technology(No.05g002).
文摘The study on the earthquake-resistant performance of a pile-soil-structure interaction system is a relatively complicated and primarily important issue in civil engineering practice. In this paper, a computational model and computation procedures for pile-supported structures, which can duly consider the pile-soil interaction effect, arc established by the finite clement method. Numerical implementation is made in the time domain. A simplified approximation for the seismic response analysis of pile-soil-structure systems is briefly presented. Then a comparative study is performed for an engineering example with numerical results computed respectively by the finite clement method and the simplified method. Through comparative analysis, it is shown that the results obtained by the simplified method well agree with those achieved by the finite element method. The numerical results and findings will offer instructive guidelines for earthquake-resistant analysis and design of pile-supported structures.
基金supported by the Swiss National Science Foundation[grant numbers 148261,170645 and 180195]by the ETH Biocommunication group.
文摘Aims Ecosystem engineers substantially modify the environment via their impact on abiotic conditions and the biota,resulting in facilitation of associated species that would not otherwise grow.Yet,reciprocal effects are poorly understood as studies of plant–plant interactions usually estimate only benefits for associated species,while how another trophic level may mediate direct and indirect feedback effects for ecosystem engineers is hardly considered.Methods We ran a field experiment with two ecosystem engineers(Arenaria tetraquetra and Hormathophylla spinosa)blooming either alone or with associated plants to decompose net effects and to test the hypothesis that pollinator-mediated interactions provide benefits that balance costs of facilitation by ecosystem engineers.Important Findings We found that net costs of facilitation are accompanied by pollinator-mediated benefits.Despite ecosystem engineers producing fewer flowers per plant,they were visited by more and more diverse pollinators per flower when blooming with associated plants than when blooming alone.Although seed production per plant was higher when ecosystem engineers bloomed alone,fruit set and seed set varied between species.In one case(A.tetraquetra),fruit and seed sets were negatively affected by the presence of associated plants,whereas,in another case(H.spinosa),fruit set and seed set were higher and unaffected when ecosystem engineers bloomed with associated plants,respectively.Our findings suggest that besides experiencing direct costs,ecosystem engineers can also benefit from facilitating other species via increasing their own visibility to pollinators.Thus,we highlight that pollination interactions can compensate for costs of facilitation depending on ecosystem engineer species.This study illuminates how the outcome of direct plant–plant interactions might be mediated by indirect interactions including third players.
基金supported by the National Natural Science Foundation of China (Grant Nos. 90715040, 50878159)
文摘Across-wind loads and effects have become increasingly important factors in the structural design of super-tall buildings and structures with increasing height. Across-wind loads and effects of tall buildings and structures are believed to be excited by inflow turbulence, wake, and inflow-structure interaction, which are very complicated. Although researchers have been focusing on the problem for over 30 years, the database of across-wind loads and effects and the computation methods of equivalent static wind loads have not yet been developed, most countries having no related rules in the load codes. Research results on the across-wind effects of tall buildings and structures mainly involve the determination of across-wind aerodynamic forces and across-wind aerodynamic damping, development of their databases, theoretical methods of equivalent static wind loads, and so on. In this paper we first review the current research on across-wind loads and effects of super-tall buildings and structures both at home and abroad. Then we present the results of our study. Finally, we illustrate a case study in which our research results are applied to a typical super-tall structure.