The core of the engineering education concepts is student-centered teaching,result-oriented teaching,and continuous improvement.It is necessary to carry out course remolding of software engineering course guided by en...The core of the engineering education concepts is student-centered teaching,result-oriented teaching,and continuous improvement.It is necessary to carry out course remolding of software engineering course guided by engineering education concepts.This paper first analyzes the pain points of teaching the course of software engineering,and then introduces how to remold the course based on engineering education concepts,including reformulating the teaching objectives,teaching modes,and assessment methods.Through teaching practice,we find that the improved course has achieved a better teaching result,which reflects the advantages of the engineering education concepts.展开更多
This paper takes "impression remolding" as the hint of design concept, analyzes uniqueness and correlation of Lijiang Train Station, and also multiple design techniques of integrating regional cultural eleme...This paper takes "impression remolding" as the hint of design concept, analyzes uniqueness and correlation of Lijiang Train Station, and also multiple design techniques of integrating regional cultural elements, such as roofi ng cluster.展开更多
The behaviors remolding of foreign language teachers (FLT) are effective and influential in eliciting the learners' interest and motivation as well as enhancing the learning proficiency. Nonverbal communication (N...The behaviors remolding of foreign language teachers (FLT) are effective and influential in eliciting the learners' interest and motivation as well as enhancing the learning proficiency. Nonverbal communication (NVC) is an essential component of human verbal communication. Sometimes it is even more powerful and expressive than verbal interactions, for they can convey such subtle feelings and fine emotions that verbal entries feel impotent of. This paper intends to make a survey on the notion of nonverbal communication and further explore the function and the significance of body language on remolding teachers' behaviors in foreign language teaching.展开更多
The protective remolding and reusing of industrial historic buildings and sites is regarded as a great scientific matter in today's urban development. Based on discussing its significance and value,this paper,taki...The protective remolding and reusing of industrial historic buildings and sites is regarded as a great scientific matter in today's urban development. Based on discussing its significance and value,this paper,taking a specific example,makes a systematic discussion on the design strategy and method from the aspects of overall planning,remolding the old buildings,designing the new buildings,etc.展开更多
The life cycle of international norms is not actually a process of emergence, diffusion and internalization. As is shown by the logic of argumentation and the relational logic of process- oriented constructivism, the ...The life cycle of international norms is not actually a process of emergence, diffusion and internalization. As is shown by the logic of argumentation and the relational logic of process- oriented constructivism, the development of intemational norms may take another approach, one of origination, diffusion and remolding. Through dialogues on norms, discourse critique, self-remolding and other means, China has enriched the practice of remolding international human rights norms with a human rights theory centered on the right to survive and develop, thereby providing a new approach and new angle of vision that allows non-Western countries to break away from the monist approach of norm development.展开更多
Being the largest comprehensive urban development project in the city of Harbin, theremolding of the north outer ring road not only improved the city’s road condition, but al-so brought along the initiatives to redev...Being the largest comprehensive urban development project in the city of Harbin, theremolding of the north outer ring road not only improved the city’s road condition, but al-so brought along the initiatives to redevelop the large number of dilapidated sheds alongthe road, transform industrial technoloqy and advance environment quality.展开更多
The classroom is an important place for“three guarantees”education.Classroom culture refers to a group culture with both teachers and students as the main body,the classroom space as the carrier,and spiritual connot...The classroom is an important place for“three guarantees”education.Classroom culture refers to a group culture with both teachers and students as the main body,the classroom space as the carrier,and spiritual connotation as the core.The creation of classroom culture with school characteristics,characteristics of the times,and Chinese characteristics can reflect the aesthetic perspective and value orientation of the school,which has far-reaching significance for the growth of students and their future development.This paper takes the construction of classroom culture in colleges and universities as the research subject,obtains real data,and conducts variable analysis through questionnaire survey and structured interview,with the aim of enriching the educational function of the classroom.It involves how the classroom culture pays attention to the current life,needs,and desires of college and university students,along with the problems and functions that should be improved in the traditional construction.This paper also discusses and reshapes the new paradigm of classroom culture construction in colleges and universities based on the combination of student growth,subject areas,school culture,and advanced technology.展开更多
OBJECTIVE The current therapeutic approaches have a limited effect on the dysregulated pulmonary vascular remodeling,which is characteristic of pulmonary arterial hypertension(PAH).In this study we exam-ined whether s...OBJECTIVE The current therapeutic approaches have a limited effect on the dysregulated pulmonary vascular remodeling,which is characteristic of pulmonary arterial hypertension(PAH).In this study we exam-ined whether salvianolic acid A(SAA)extracted from the traditional Chinese medicine′Dan Shen′attenuated vascular remodeling in a PAH rat model,and elucidated the underlying mechanisms.METHODS PAH was induced in rats by injecting a single dose of monocrotaline(MCT 60 mg·kg-1,sc).The rats were orally treated with either SAA(0.3,1,3 mg·kg-1·d-1)or a positive control bosentan(30 mg·kg-1·d-1)for 4 weeks.Echocardiography and hemodynamic measurements were performed on d 28.Then the hearts and lungs were harvested,the organ indices and pulmonary artery wall thickness were calculated,and biochemical and histochemical analysis were conducted.The levels of apoptotic and signaling proteins in the lungs were measured using immunoblotting.RESULTS Treatment with SAA or bosentan effectively ameliorated MCTinduced pulmonary artery remodeling,pulmonary hemodynamic abnormalities and the subsequent increases of right ventricular systolic pressure(RVSP).Furthermore,the treatments significantly attenuated MCT-induced hypertrophic damage of myocardium,parenchymal injury and collagen deposition in the lungs.Moreover,the treatments attenuated MCT-induced apoptosis and fibrosis in the lungs.The treatments partially restored MCT-induced reductions of bone morphogenetic protein typeⅡreceptor(BMPRⅡ)and phosphorylated Smad1/5 in the lungs.CONCLUSION SAA ameliorates the pulmonary arterial remodeling in MCT-induced PAH rats most likely via activating the BMPRⅡ-Smad pathway and inhibiting apoptosis.Thus,SAA may have therapeutic potential for the patients at high risk of PAH.展开更多
Chandler proposed the intrinsic strength line to correlate the undrained shear strength of samples one-dimensionally consolidated from slurry with the void index proposed by Burland. The undrained shear strength on th...Chandler proposed the intrinsic strength line to correlate the undrained shear strength of samples one-dimensionally consolidated from slurry with the void index proposed by Burland. The undrained shear strength on the intrinsic strength line is different from the remolded undrained shear strength that is an important parameter for design and construction of land reclamation. The void index is used in this study for normalizing the remolded strength behavior of dredged deposits. A quantitative relationship between remolded undrained shear strength and void index is established based on extensive data of dredged deposits available from sources of literature. Furthermore, the normalized remolded undrained shear strength is compared with intrinsic strength line. The comparison result indicates that the ratio of undrained shear strength on the intrinsic strength line over remolded undrained shear strength increases with an increase in applied consolidated stress.展开更多
Extensive data of undrained shear strength for various remolded soils are compiled to normalize the remolded undrained strength. Remolded soils have a wide spectrum of liquid limits ranging from 25% to 412%. It is fou...Extensive data of undrained shear strength for various remolded soils are compiled to normalize the remolded undrained strength. Remolded soils have a wide spectrum of liquid limits ranging from 25% to 412%. It is found that the remolded undrained strength is a function of water content and liquid limit. Furthermore, a simple index designated as normalized water content w * is introduced for normalizing remolded undrained strength for various soils. The normalized water content w * is the ratio of water content to liquid limit. The relationship between the remolded undrained strength and the normalized water content can be expressed by a simple equation. The new simple equation is not only valuable theoretically for helping in assessing the in situ mechanical behavior, but also useful to ocean engineering practice.展开更多
The strength of structural loess consists of the shear strength and tensile strength. In this study, the stress path, the failure envelope of principal stress ( Kf line), and the strength failure envelope of structu...The strength of structural loess consists of the shear strength and tensile strength. In this study, the stress path, the failure envelope of principal stress ( Kf line), and the strength failure envelope of structurally intact loess and remolded loess were analyzed through three kinds of tests: the tensile strength test, the uniaxial compressive strength test, and the conventional triaxial shear strength test. Then, in order to describe the tensile strength and shear strength of structural loess comprehensively and reasonably, a joint strength formula for structural loess was established. This formula comprehensively considers tensile and shear properties. Studies have shown that the tensile strength exhibits a decreasing trend with increasing water content. When the water content is constant, the tensile strength of the structurally intact soil is greater than that ofremolded soil. In the studies, no loss of the originally cured cohesion in the structurally intact soil samples was observed, given that the soil samples did not experience loading disturbance during the uniaxial compressive strength test, meaning there is a high initial structural strength. The results of the conventional triaxial shear strength test show that the water content is correlated with the strength of the structural loess. When the water content is low, the structural properties are strong, and when the water content is high, the structural properties are weak, which means that the water content and the ambient pressure have significant effects on the stress-strain relationship of structural loess. The established joint strength formula of structural loess effectively avoids overestimating the role of soil tensile strength in the traditional theory of Mohr-Coulomb strength.展开更多
The compression behavior responsible for unity sensitivity is very valuable in quantitative assessment of the effects of soil structure on the compression behavior of soft marine sediments. However, the quantitative a...The compression behavior responsible for unity sensitivity is very valuable in quantitative assessment of the effects of soil structure on the compression behavior of soft marine sediments. However, the quantitative assessment of such effects is not possible because of unavailability of the formula for the compression curve of marine sediments responsible for unit sensitivity. In this study, the relationship between the remolded state and the conventional critical state line is presented in the deviator stress versus mean effective stress plot. The analysis indicates that the remolded state is on the conventional critical state line obtained at a relatively small strain. Thus, a unique critical state sedimentation line for marine sediments of unit sensitivity is proposed. The comparison between the critical state sedimentation line proposed in this study and the existing normalized consolidation curves obtained from conventional oedometer tests on remolded soils or reconstituted soils explains well the展开更多
Pressure plate instrument is employed during drying, and unconfined compressive strength test is performed on the unsaturated specimen. Curves of shear force versus shear displacement, and curves of saturation degree ...Pressure plate instrument is employed during drying, and unconfined compressive strength test is performed on the unsaturated specimen. Curves of shear force versus shear displacement, and curves of saturation degree versus time are investigated. The results show that the specimens with similar curves of saturation degree versus time have nearly identical mechanical behavior. In particular, the uniform specimens should be chosen within the lower equilibrium saturation degree because steady test results are presented. Further, the conclusion is verified by the repeated test. Thus, the method for distinguishing the uniform unsaturated specimen is obtained. In the light of the method, an improved test process is proposed. The uniform specimens should be chosen by this method under the specific matric suction, and then shear tests are carried out on the chosen unsaturated specimen. Namely, initial value of unsaturated soil is not zero matric suction but a specific suction.展开更多
A method of obtaining the large strain consolidation parameters of dredged clays considering the influence of the initial water content is investigated in this study. According to the test results of remolded clays wi...A method of obtaining the large strain consolidation parameters of dredged clays considering the influence of the initial water content is investigated in this study. According to the test results of remolded clays with high initial water contents reported by Hong et al. (2010), a relationship between the void ratio (e) and effective stress (a3 is established. Furthermore, based on the available permeability data from the literature, a new relationship between the permeability coefficient (k) and the ratio (e/eL) of the void ratio to the void ratio at the liquid limit (eL) is proposed. The new proposed expression considering the initial water content improves the e-k equation established by Nagaraj et al. (1994). Finally, the influence of the initial void ratio and effective stress on the large strain consolidation coefficient g(e) defined by Gibson et al. (1981) and k/(1 +e) in large strain analysis is discussed. The results show that, under a constant effective stress, the value of k/(1 +e) increases with the initial void ratio. The large strain consolidation coefficient shows the law of segmentation change, which decreases with the increase of the effective stress when the effective stress is less than the remolded yield stress, but increases rapidly with the effective stress when the effective stress is larger than the remolded yield stress.展开更多
Evaluating the impacts of soil structure on mechanical behavior for natural sedimentary clays is an important issue in geotechnical engineering. Burland introduced void index for normalizing the compression curves of ...Evaluating the impacts of soil structure on mechanical behavior for natural sedimentary clays is an important issue in geotechnical engineering. Burland introduced void index for normalizing the compression curves of various remolded and reconstituted clays to obtain the intrinsic compression line, which provides a reference framework to assess the in-situ compression behavior. However, it does not quantitatively account for the effects of initial water content on compressive behavior of remolded and reconstituted clays and the initial water contents of clays are not always limited to 1.0 - 1.5 times the liquid limits defined by Burland. A modification based on collected tests data was presented on the expressions of ?and ?defined by Burland. Extensive oedometer test data were also collected on various remolded and reconstituted soils with distinct liquid limits and initial water contents to verify the validity of modified expressions. A normalized compression line deduced by intrinsic compression line is proposed in the e-log p plot, which can be used to evaluate the effects of soil structure quantitatively on the intact compressive behavior for natural sedimentary clays.展开更多
Regulatory science for medical devices aims to develop new tools,standards and approaches to assess the safety,effectiveness,quality and performance of medical devices.In the field of biomaterials,hernia mesh is a cla...Regulatory science for medical devices aims to develop new tools,standards and approaches to assess the safety,effectiveness,quality and performance of medical devices.In the field of biomaterials,hernia mesh is a class of implants that have been successfully translated to clinical applications.With a focus on hernia mesh and its regulatory science system,this paper collected and reviewed information on hernia mesh products and biomaterials in both Chinese and American markets.The current development of regulatory science for hernia mesh,including its regulations,standards,guidance documents and classification,and the scientific evaluation of its safety and effectiveness was first reported.Then the research prospect of regulatory science for hernia mesh was discussed.New methods for the preclinical animal study and new tools for the evaluation of the safety and effectiveness of hernia mesh,such as computational modeling,big data platform and evidence-based research,were assessed.By taking the regulatory science of hernia mesh as a case study,this review provided a research basis for developing a regulatory science system of implantable medical devices,furthering the systematic evaluation of the safety and effectiveness of medical devices for better regulatory decision-making.This was the first article reviewing the regulatory science of hernia mesh and biomaterial-based implants.It also proposed and explained the concepts of evidence-based regulatory science and technical review for the first time.展开更多
一、引言1913年,上海广学会(Christian Literature Society)推出了英国传教士李提摩太(Timothy Richard)的《西游记》英译本《天国之行:一部伟大的中国史诗和寓言》(A Mission to Heaven:A Great Chinese Epic andAllegory),在此之前,...一、引言1913年,上海广学会(Christian Literature Society)推出了英国传教士李提摩太(Timothy Richard)的《西游记》英译本《天国之行:一部伟大的中国史诗和寓言》(A Mission to Heaven:A Great Chinese Epic andAllegory),在此之前,《西游记》的"英文翻译是片段式的"①。尽管李氏的《西游记》译本也只是"《西游记》的一个轮廓"②.展开更多
In this paper,three-dimensional(3D)finite element analyses of a real-scale group-pile foundation subjected to horizontal cyclic loading are conducted using a program named DBLEAVES.In the simulations,nonlinear behavio...In this paper,three-dimensional(3D)finite element analyses of a real-scale group-pile foundation subjected to horizontal cyclic loading are conducted using a program named DBLEAVES.In the simulations,nonlinear behaviors of ground and piles are described by subloading tij.model and the axial-force dependent model(AFD model)which considered the axial-force dependency in the nonlinear moment-curvature relations.In order to consider the influence of an effective stress path on the prediction of the group-pile foundation,the analyses are conducted within the framework of the soil-water coupling method with finite-difference and finite-element regime.The material parameters of soils are determined based on conventional triaxial drained compression tests on undisturbed and remolded specimens.The applicability of the proposed numerical method is encouraging,and therefore,it is quite confident to say that the method can be used to predict the mechanical behaviors of group-pile foundation to a satisfactory accuracy,particularly with the effective stress analysis.展开更多
基金supported by the Project of Teaching Research of Anqing Normal University(Project number:2022aqnujyxm20)the Project of Innovation and Entrepreneurship Training for University Students of Anqing Normal University(Project numbers:X202310372033 and X202310372005)the Project of Quality Engineering of Anhui Province(Project number:2022xsxx119).
文摘The core of the engineering education concepts is student-centered teaching,result-oriented teaching,and continuous improvement.It is necessary to carry out course remolding of software engineering course guided by engineering education concepts.This paper first analyzes the pain points of teaching the course of software engineering,and then introduces how to remold the course based on engineering education concepts,including reformulating the teaching objectives,teaching modes,and assessment methods.Through teaching practice,we find that the improved course has achieved a better teaching result,which reflects the advantages of the engineering education concepts.
文摘This paper takes "impression remolding" as the hint of design concept, analyzes uniqueness and correlation of Lijiang Train Station, and also multiple design techniques of integrating regional cultural elements, such as roofi ng cluster.
文摘The behaviors remolding of foreign language teachers (FLT) are effective and influential in eliciting the learners' interest and motivation as well as enhancing the learning proficiency. Nonverbal communication (NVC) is an essential component of human verbal communication. Sometimes it is even more powerful and expressive than verbal interactions, for they can convey such subtle feelings and fine emotions that verbal entries feel impotent of. This paper intends to make a survey on the notion of nonverbal communication and further explore the function and the significance of body language on remolding teachers' behaviors in foreign language teaching.
基金Supported by the Key Program of the National Natural Science Foundation of China (Grant No. 50878042)
文摘The protective remolding and reusing of industrial historic buildings and sites is regarded as a great scientific matter in today's urban development. Based on discussing its significance and value,this paper,taking a specific example,makes a systematic discussion on the design strategy and method from the aspects of overall planning,remolding the old buildings,designing the new buildings,etc.
文摘The life cycle of international norms is not actually a process of emergence, diffusion and internalization. As is shown by the logic of argumentation and the relational logic of process- oriented constructivism, the development of intemational norms may take another approach, one of origination, diffusion and remolding. Through dialogues on norms, discourse critique, self-remolding and other means, China has enriched the practice of remolding international human rights norms with a human rights theory centered on the right to survive and develop, thereby providing a new approach and new angle of vision that allows non-Western countries to break away from the monist approach of norm development.
文摘Being the largest comprehensive urban development project in the city of Harbin, theremolding of the north outer ring road not only improved the city’s road condition, but al-so brought along the initiatives to redevelop the large number of dilapidated sheds alongthe road, transform industrial technoloqy and advance environment quality.
文摘The classroom is an important place for“three guarantees”education.Classroom culture refers to a group culture with both teachers and students as the main body,the classroom space as the carrier,and spiritual connotation as the core.The creation of classroom culture with school characteristics,characteristics of the times,and Chinese characteristics can reflect the aesthetic perspective and value orientation of the school,which has far-reaching significance for the growth of students and their future development.This paper takes the construction of classroom culture in colleges and universities as the research subject,obtains real data,and conducts variable analysis through questionnaire survey and structured interview,with the aim of enriching the educational function of the classroom.It involves how the classroom culture pays attention to the current life,needs,and desires of college and university students,along with the problems and functions that should be improved in the traditional construction.This paper also discusses and reshapes the new paradigm of classroom culture construction in colleges and universities based on the combination of student growth,subject areas,school culture,and advanced technology.
基金Natural Science Foundation of China(81573645,81603101)the National Science and Technology Major Project(2013ZX09103001-008)
文摘OBJECTIVE The current therapeutic approaches have a limited effect on the dysregulated pulmonary vascular remodeling,which is characteristic of pulmonary arterial hypertension(PAH).In this study we exam-ined whether salvianolic acid A(SAA)extracted from the traditional Chinese medicine′Dan Shen′attenuated vascular remodeling in a PAH rat model,and elucidated the underlying mechanisms.METHODS PAH was induced in rats by injecting a single dose of monocrotaline(MCT 60 mg·kg-1,sc).The rats were orally treated with either SAA(0.3,1,3 mg·kg-1·d-1)or a positive control bosentan(30 mg·kg-1·d-1)for 4 weeks.Echocardiography and hemodynamic measurements were performed on d 28.Then the hearts and lungs were harvested,the organ indices and pulmonary artery wall thickness were calculated,and biochemical and histochemical analysis were conducted.The levels of apoptotic and signaling proteins in the lungs were measured using immunoblotting.RESULTS Treatment with SAA or bosentan effectively ameliorated MCTinduced pulmonary artery remodeling,pulmonary hemodynamic abnormalities and the subsequent increases of right ventricular systolic pressure(RVSP).Furthermore,the treatments significantly attenuated MCT-induced hypertrophic damage of myocardium,parenchymal injury and collagen deposition in the lungs.Moreover,the treatments attenuated MCT-induced apoptosis and fibrosis in the lungs.The treatments partially restored MCT-induced reductions of bone morphogenetic protein typeⅡreceptor(BMPRⅡ)and phosphorylated Smad1/5 in the lungs.CONCLUSION SAA ameliorates the pulmonary arterial remodeling in MCT-induced PAH rats most likely via activating the BMPRⅡ-Smad pathway and inhibiting apoptosis.Thus,SAA may have therapeutic potential for the patients at high risk of PAH.
文摘Chandler proposed the intrinsic strength line to correlate the undrained shear strength of samples one-dimensionally consolidated from slurry with the void index proposed by Burland. The undrained shear strength on the intrinsic strength line is different from the remolded undrained shear strength that is an important parameter for design and construction of land reclamation. The void index is used in this study for normalizing the remolded strength behavior of dredged deposits. A quantitative relationship between remolded undrained shear strength and void index is established based on extensive data of dredged deposits available from sources of literature. Furthermore, the normalized remolded undrained shear strength is compared with intrinsic strength line. The comparison result indicates that the ratio of undrained shear strength on the intrinsic strength line over remolded undrained shear strength increases with an increase in applied consolidated stress.
基金ThisresearchprojectwasfinanciallysupportedbytheMinistryofScienceandTechnology Japan (DomesticResearchFellowship 1999 2 0 0 1) .
文摘Extensive data of undrained shear strength for various remolded soils are compiled to normalize the remolded undrained strength. Remolded soils have a wide spectrum of liquid limits ranging from 25% to 412%. It is found that the remolded undrained strength is a function of water content and liquid limit. Furthermore, a simple index designated as normalized water content w * is introduced for normalizing remolded undrained strength for various soils. The normalized water content w * is the ratio of water content to liquid limit. The relationship between the remolded undrained strength and the normalized water content can be expressed by a simple equation. The new simple equation is not only valuable theoretically for helping in assessing the in situ mechanical behavior, but also useful to ocean engineering practice.
基金supported by the National Natural Science Foundation of China(Grant No.11072193)the Fundamental Research Funds for the Central Universities(Grant No.2013G1502009)the China Postdoctoral Science Foundation(Grant No.20100481354)
文摘The strength of structural loess consists of the shear strength and tensile strength. In this study, the stress path, the failure envelope of principal stress ( Kf line), and the strength failure envelope of structurally intact loess and remolded loess were analyzed through three kinds of tests: the tensile strength test, the uniaxial compressive strength test, and the conventional triaxial shear strength test. Then, in order to describe the tensile strength and shear strength of structural loess comprehensively and reasonably, a joint strength formula for structural loess was established. This formula comprehensively considers tensile and shear properties. Studies have shown that the tensile strength exhibits a decreasing trend with increasing water content. When the water content is constant, the tensile strength of the structurally intact soil is greater than that ofremolded soil. In the studies, no loss of the originally cured cohesion in the structurally intact soil samples was observed, given that the soil samples did not experience loading disturbance during the uniaxial compressive strength test, meaning there is a high initial structural strength. The results of the conventional triaxial shear strength test show that the water content is correlated with the strength of the structural loess. When the water content is low, the structural properties are strong, and when the water content is high, the structural properties are weak, which means that the water content and the ambient pressure have significant effects on the stress-strain relationship of structural loess. The established joint strength formula of structural loess effectively avoids overestimating the role of soil tensile strength in the traditional theory of Mohr-Coulomb strength.
基金This research project was financially supported by the Ministry of Science and Technology, Japan(Domestic Research Fellowship, 1999-2001)
文摘The compression behavior responsible for unity sensitivity is very valuable in quantitative assessment of the effects of soil structure on the compression behavior of soft marine sediments. However, the quantitative assessment of such effects is not possible because of unavailability of the formula for the compression curve of marine sediments responsible for unit sensitivity. In this study, the relationship between the remolded state and the conventional critical state line is presented in the deviator stress versus mean effective stress plot. The analysis indicates that the remolded state is on the conventional critical state line obtained at a relatively small strain. Thus, a unique critical state sedimentation line for marine sediments of unit sensitivity is proposed. The comparison between the critical state sedimentation line proposed in this study and the existing normalized consolidation curves obtained from conventional oedometer tests on remolded soils or reconstituted soils explains well the
基金Project(51179023) supported by the National Natural Science Foundation of China
文摘Pressure plate instrument is employed during drying, and unconfined compressive strength test is performed on the unsaturated specimen. Curves of shear force versus shear displacement, and curves of saturation degree versus time are investigated. The results show that the specimens with similar curves of saturation degree versus time have nearly identical mechanical behavior. In particular, the uniform specimens should be chosen within the lower equilibrium saturation degree because steady test results are presented. Further, the conclusion is verified by the repeated test. Thus, the method for distinguishing the uniform unsaturated specimen is obtained. In the light of the method, an improved test process is proposed. The uniform specimens should be chosen by this method under the specific matric suction, and then shear tests are carried out on the chosen unsaturated specimen. Namely, initial value of unsaturated soil is not zero matric suction but a specific suction.
基金supported by the Innovation Program for 2011 College Graduates of Jiangsu Province(Grant No.CXZZ_0158)the National Natural Science Foundation of China(Grant No.51178107)
文摘A method of obtaining the large strain consolidation parameters of dredged clays considering the influence of the initial water content is investigated in this study. According to the test results of remolded clays with high initial water contents reported by Hong et al. (2010), a relationship between the void ratio (e) and effective stress (a3 is established. Furthermore, based on the available permeability data from the literature, a new relationship between the permeability coefficient (k) and the ratio (e/eL) of the void ratio to the void ratio at the liquid limit (eL) is proposed. The new proposed expression considering the initial water content improves the e-k equation established by Nagaraj et al. (1994). Finally, the influence of the initial void ratio and effective stress on the large strain consolidation coefficient g(e) defined by Gibson et al. (1981) and k/(1 +e) in large strain analysis is discussed. The results show that, under a constant effective stress, the value of k/(1 +e) increases with the initial void ratio. The large strain consolidation coefficient shows the law of segmentation change, which decreases with the increase of the effective stress when the effective stress is less than the remolded yield stress, but increases rapidly with the effective stress when the effective stress is larger than the remolded yield stress.
文摘Evaluating the impacts of soil structure on mechanical behavior for natural sedimentary clays is an important issue in geotechnical engineering. Burland introduced void index for normalizing the compression curves of various remolded and reconstituted clays to obtain the intrinsic compression line, which provides a reference framework to assess the in-situ compression behavior. However, it does not quantitatively account for the effects of initial water content on compressive behavior of remolded and reconstituted clays and the initial water contents of clays are not always limited to 1.0 - 1.5 times the liquid limits defined by Burland. A modification based on collected tests data was presented on the expressions of ?and ?defined by Burland. Extensive oedometer test data were also collected on various remolded and reconstituted soils with distinct liquid limits and initial water contents to verify the validity of modified expressions. A normalized compression line deduced by intrinsic compression line is proposed in the e-log p plot, which can be used to evaluate the effects of soil structure quantitatively on the intact compressive behavior for natural sedimentary clays.
基金The authors thank the financial support from National Natural Science Foundation of China(51973018)National Natural Science Foundation of China(51773018)Beijing Municipal Science and Technology Commission Projects(No.Z191100002019017).
文摘Regulatory science for medical devices aims to develop new tools,standards and approaches to assess the safety,effectiveness,quality and performance of medical devices.In the field of biomaterials,hernia mesh is a class of implants that have been successfully translated to clinical applications.With a focus on hernia mesh and its regulatory science system,this paper collected and reviewed information on hernia mesh products and biomaterials in both Chinese and American markets.The current development of regulatory science for hernia mesh,including its regulations,standards,guidance documents and classification,and the scientific evaluation of its safety and effectiveness was first reported.Then the research prospect of regulatory science for hernia mesh was discussed.New methods for the preclinical animal study and new tools for the evaluation of the safety and effectiveness of hernia mesh,such as computational modeling,big data platform and evidence-based research,were assessed.By taking the regulatory science of hernia mesh as a case study,this review provided a research basis for developing a regulatory science system of implantable medical devices,furthering the systematic evaluation of the safety and effectiveness of medical devices for better regulatory decision-making.This was the first article reviewing the regulatory science of hernia mesh and biomaterial-based implants.It also proposed and explained the concepts of evidence-based regulatory science and technical review for the first time.
文摘一、引言1913年,上海广学会(Christian Literature Society)推出了英国传教士李提摩太(Timothy Richard)的《西游记》英译本《天国之行:一部伟大的中国史诗和寓言》(A Mission to Heaven:A Great Chinese Epic andAllegory),在此之前,《西游记》的"英文翻译是片段式的"①。尽管李氏的《西游记》译本也只是"《西游记》的一个轮廓"②.
文摘In this paper,three-dimensional(3D)finite element analyses of a real-scale group-pile foundation subjected to horizontal cyclic loading are conducted using a program named DBLEAVES.In the simulations,nonlinear behaviors of ground and piles are described by subloading tij.model and the axial-force dependent model(AFD model)which considered the axial-force dependency in the nonlinear moment-curvature relations.In order to consider the influence of an effective stress path on the prediction of the group-pile foundation,the analyses are conducted within the framework of the soil-water coupling method with finite-difference and finite-element regime.The material parameters of soils are determined based on conventional triaxial drained compression tests on undisturbed and remolded specimens.The applicability of the proposed numerical method is encouraging,and therefore,it is quite confident to say that the method can be used to predict the mechanical behaviors of group-pile foundation to a satisfactory accuracy,particularly with the effective stress analysis.