摘要：The objective of this study was to investigate the mechanical characteristics of implant-abutment interface design in a dental implant system, using nonlinear finite element analysis （FEA） method. This finite element simulation study was applied on three commonly used commercial dental implant systems： model I, the reduced-diameter 3i implant system （West Palm Beach, FL, USA） with a hex and a 12-point double internal hexagonal connection; model II, the Semados implant system （Bego, Bremen, Germany） with combination of a conical （45° taper） and internal hexagonal connection; and model III, the Br,~nemark implant system （Nobel Biocare, Gothenburg, Sweden） with external hexagonal connection. In simulation, a force of 170 N with 45°oblique to the longitudinal axis of the implant was loaded to the top surface of the abutment. It has been found from the strength and stiffness analysis that the 3i implant system has the lowest maximum yon Mises stress, prirlcipal stress and displacement, while the Br^nemark implant system has the highest. It was concluded from our preliminary study using nonlinear FEA that the reduced-diameter 3i implant system with a hex and a 12-point double internal hexagonal connection had a better stress distribution, and produced a smaller displacement than the other two implant systems.

摘要：The efficacy of shape control is the core of this technology and the main basis of automatic shape control system model designing. This passage constructs the three-dimensional elastic deformation model of CVCplus roll system in 2250 mm hot rolling mill. Comparing and analyzing different influence of working factors on control characteristic, the shape control characteristic of CVCplus roll system in its whole work time is studied, and the cause is analyzed and the difference of the roll gap curve and crown adjustable area in early and latter work time is compared. The outcome has crucial meaning in both theory and production.

摘要：Stiffener is the important missile structure to ensure the structural strength of the missile. In order to improve the design efficiency and the quality of the missile stiffener, the methods of missile stiffener rapid modeling and analysis are proposed. First, the problems of traditional manual modeling of the stiffener are analyzed. According to the problems and actual requirement of modeling, volume decomposition method is used to divide the stiffener into the upper section, the lower section and the web in order for feature analysis and parameter extraction. Then based on the parameters the basic unit decomposed above is created for Boolean operation to establish the stiffener. Finally, a rapid stiffener modeling and analysis program were developed based on UG Open API, the modeling and analysis result validates the feasibility of the method.

摘要：Total temporomandibular joint(TMJ)replacement is recommended only when there is irreversible damage to the joint and no conservative treatment can provide functional *** stock and custom-made TMJ implants have been made available;however,retrospective and comparative studies were unable to find significant differences between the two types of *** introduction of additive manufacturing(AM)techniques in medical practice allows for a greater freedom of design and a higher degree of device *** combination of AM with structural optimisation may streamline development and provide the key for fabricating biomechanic ally enhanced TMJ *** this study,structural optimis ation techniques were applied to develop and numerically validate a patient-specific TMJ *** biomechanical behaviour of each intermediate TMJ design was assessed under four different nominal and maximum biting tasks using finite element *** addition,a new set of metrics were proposed to compare each design regarding biomechanical performance and implant *** results suggest that 55-82%of the natural/intact strain patterns can be recovered with the finally selected TMJ *** represents an increase of 15%in biomechanical performance for incisor biting,15%for right molar biting,17%for left molar biting and a decrease of 2%for left group biting compared with the initial *** results also suggest that load transfer at the proximal ramus reduces the implant’s impact on the mandible’s strain ***,structural optimisation allows for a volume reduction of up to 44%with a minimum loss of implant safety and biomechanical performance.

摘要：A new multi-functional bridge seismic isolation bearing(MFBSIB) is designed and its mechanical model is developed in this *** an upper sliding device and a lower energy dispassion isolation device effectively,the new MFBSIB can adjust the deformation caused by temperature,vehicle breaks,and concrete creep,etc.,in addition to dissipating *** switch of 'slide-isolation' is achieved and the efficiency of both upper and lower parts is validated through experiment with a *** shear performance curve established in this paper is verified to be efficient in describing the mechanical characteristics of the bearing through *** is proved through both numerical calculation and experimental analysis that the new MFBSIB is endowed with enough vertical rigidity,good energy dissipation ability,stable overall performance,and good realization in expected *** performance is slightly influenced by shear stress,while affected by vertical pressure,loading frequency,slide limit,etc.,*** results could provide reference for study and application of the new MFBSIB.

摘要：A novel reconstructive prosthesis was designed with topological optimization(TO)and a lattice structure to enhance biomechanical and biological properties in the proximal *** biomechanical performance was validated through finite element analysis(FEA)and biomechanical *** tibia with inhomogeneous material properties was reconstructed according to computed tomography images,and different components were designed to simulate the *** compliance TO subject to a volume fraction constraint combined with a graded lattice structure was utilized to redesign the *** was performed to evaluate the mechanical performances of the tibia and implants after optimization,including stress,micromotion,and strain *** results were analyzed by paired-samples t tests,and p<0.05 was considered *** testing was used to verify the tibial *** to the original group(OG),the TO group(TOG)exhibited lower stress on the stem,and the maximum von Mises stresses were 87.2 and 53.1 MPa,respectively,a 39.1%reduction(p<0.05).Conversely,the stress and strain energy on the tibia increased in the *** maximum von Mises stress values were 16.4 MPa in the OG and 22.9 MPa in the TOG with a 39.6%increase(p<0.05),and the maximum SED value was 0.026 MPa in the OG and 0.042 MPa in the TOG,corresponding to an increase of 61.5%(p<0.05).The maximum micromotions in the distal end of the stem were 135μm in the OG and 68μm in the TOG,almost a 50%*** stress curves of the biomechanical test coincided well with the FEA *** TO approach can effectively reduce the whole weight of the prosthesis and improve the biomechanical environment of the *** could also pave the way for next-generation applications in orthopedics surgery.

摘要：Background There is a relatively high failure rate of the femoral component in patients with avascular necrosis at the intermediate-term follow-up. Improving the geometrical fit of the femoral stem against the medullary canal may help to provide long-term survivorship of the hip replacement for patients with avascular necrosis. Methods We designed a specific stem, based on morphometric studies of proximal femoral canals in Chinese avascular necrosis patients and evaluated the stem by finite element analyses, comparing the novel stem with two commercially available and commonly used stems. Results The morphometric data from avascular necrosis patients showed specific geometric differences in the proximal femoral canal, including profile curves in both the sagittal and coronary planes than the patients with femoral neck fracture. The shorter stemmed prostheses （FitmoreR and our stem） performed better than the longer stemmed prosthesis （VerSysR）. Conclusions This is the first study to investigate the femoral geometries of Chinese avascular necrosis patients. Our stem provides better stability and is theoretically beneficial to bone ingrowth, which may increase the long-term stability and fixation of the implant.

摘要：A double-walled tubular component can be formed from a metal tube under axial compression by inversion. Numerical simulation and experimental investigation show that die radius is the predominant factor affecting the deformation process. For the given dimensions of 3A21 aluminium alloy tube, the feasible die radius varies between 2-4mm. The deformation process predicted by the finite element simulation agrees with the experiment results well.

摘要：To achieve human lower limbs rehabilitation training, the exoskeleton lower limbs rehabilitation robot is designed. Through respective motor driving, the retarding mechanism and telescopic adjusting mechanism, the function of human walking is accomplished. After the design of the mechanical structure, the finite element analysis is carried out on the important parts and the control system is achieved by Single Chip Microcomputer.

摘要：The analytical and finite element analyses of circular resonator for Resonant Pressure Sensor are presented. The new idea of this paper is the Silicon circular diaphragm used as the sensing resonator for micro pressure sensor. The thickness, radius and natural frequencies for the Si circular diaphragm are investigated. A system model is being developed to predict dynamic responses of the pressure sensor diaphragm and preliminary results are presented. The pressure range is 0-0.1Mpa. The resonant frequencies output of the homogenous circular diaphragm also realized by ANSYS software. The natural frequency of the resonator is about 63.418 kHz.