Research on subsidence method aided by water injection and its engineering application for the north anchor of Taizhou Bridge

The north anchorage caisson of Taizhou Bridge encountered some difficulties during the sinking process for the large sidewall frictional resistances. To solve this problem, a new concept and method called subsidence method aided by water injection is proposed. Numeral analysis is adopted to simulate the effects of this method for the north anchor of Taizhou Bridge, which confirmed the feasibility and validity. Finally, the method is applied to the north anchor caisson during the caisson sinking procedure and helps the caisson sink and embed to the designed position smoothly.

New Scenarios for a Shift towards Agroecology in Viticulture

In the light of its negative impacts on the environment and human health, conventional agriculture is currently facing new challenges;for example, reducing pesticide reliance, improving biodiversity, adapting to climate change and reconciling winegrowers with consumers, which require changes to be made to vineyard management. A shift towards more sustainable agriculture via the development of agroecological systems may be key to meeting these environmental, economic and social challenges. This study aimed to evaluate the performance of existing viticultural systems, as well as that of three new scenarios that we built to change conventional vine production systems and their related practices. The end aim is to adopt the principles of agroecology, and more virtuously, to ensure that vine production remains in line with societal expectations. First, thirty-eight different viticultural systems were chosen. Three realistic scenarios for changing these production systems were then built by working with stakeholders and incorporating the best practices that had been identified in the vineyard. Conventional practices were optimised in the first scenario and an agroecological approach was adopted for the other two scenarios: an Agroecological scenario (using synthetic chemicals) and an Agroecological-Bio scenario (organic system). All three scenarios were based on a combination of good practices which contribute to enhancing vineyard biodiversity, and which thus restore biological regulation and in turn reduce pesticides. The viticultural systems performances have been evaluated with a methodology involving multicriteria decision aid using ELECTRE Tri-C and ELECTRE III methods. Seven evaluation criteria were selected which covered socio-economic performance (economic profitability, workload and system complexity) and environmental performance (pesticide pressure, pesticide ecotoxicity, agroecological practices and pesticide drift). The best performances were achieved by the two agroecological scenarios, and this methodology can be adaptable to different production systems everywhere in different viticultural regions.

CHARACTERISTICS OF LIP-MOUTH REGION IN SMILING POSITION FROM 80 PERSONS WITH ACCEPTABLE FACES AND INDIVIDUAL NORMAL OCCLUSIONS

OBJECTIVE: The characteristics of lip-mouth region including the soft and hard tissues in smiling position with frontal fixed position photographic computer-aided analysis were studied. METHODS: The subjects were 80 persons (40 male and 40 females, age range: 17 to approximately 25 years) with acceptable faces and individual normal occlusions. The subjects were asked to take maximum smiling position to accept photographic measurement with computer-aided analysis. RESULTS: The maximum smile line could be divided into 3 categories: low smile line (16.25%), average smile line (68.75%), and high smile line (15%). CONCLUSION: The method adopting maximum smiling position to study the lip-month region is reproducible and comparable. This study would be helpful to provide a quantitative reference for clinical investigation, diagnosis, treatment and efficacy appraisal.

A finite-element-aided ultrasonic method for measuring central oil-film thickness in a roller-raceway tribo-pair

Roller bearings support heavy loads by riding on an ultra-thin oil film(between the roller and raceway),the thickness of which is critical as it reflects the lubrication performance.Ultrasonic interfacial reflection,which facilitates the non-destructive measurement of oil-film thickness,has been widely studied.However,insufficient spatial resolution around the rolling line contact zone remains a barrier despite the use of miniature piezoelectric transducers.In this study,a finite-element-aided method is utilized to simulate wave propagation through a three-layered structure of roller-oil-raceway under elastohydrodynamic lubrication(EHL)with nonlinear characteristics of the i)deformed curvature of the cylindrical roller and ii)nonuniform distribution of the fluid bulk modulus along the circumference of the oil layer being considered.A load and speed-dependent look-up table is then developed to establish an accurate relationship between the overall reflection coefficient(directly measured by an embedded ultrasonic transducer)and objective variable of the central oil-film thickness.The proposed finite-element-aided method is verified experimentally in a rollerraceway test rig with the ultrasonically measured oil-flm thickness corresponding to the values calculated using the EHLtheory.

A new approach on necking constitutive relationships of ductile materials at elevated temperatures

A new method is presented to determine the full-range, uniaxial constitutive relationship of materials by tensile tests on funnel specimens with small curvature radius and finite element analysis(FEA). An iteration method using FEA APDL(ANSYS parametric design language) programming has been developed to approach the necking constitutive relationship of materials. Test results from SAE 304 stainless steel at room temperature show that simulated load vs displacement curve,diameter at funnel root vs displacement curve, and funnel deformation contours are close to modeled results. Due to this new method, full-range constitutive relationships and true stress and effective true strain at failure are found for 316 L stainless steel, TA17 titanium alloy and A508-III stainless steel at room temperature, and 316 L stainless steel at various elevated temperatures.