The problem always exist in foundation pit engineering that the support axial force can not be regulated in the pit system in real time.According to setting the axial force compensation system,the problem would be solved perfectly and efficiently,realizing the fact control and adjust the support axial force and stability. The axial force compensation system which is constituted by jacks distributed in the pit has been confirmed the significant role to control foundation pit deformation and internal force monitoring combined with practical engineering
In order to realize the miniaturization of fuze safety mechanism, a novel MEMS safe and arm is proposed through concept, analysis, design and initial prototyping. A microscale inertial mechanical logic for mechanical safe and arm functions in the form of sliders, springs, and locks that interact on a planar substrate in response to setback acceleration and centrifugal force to thereby arm the fuze, and the bulk fabrication process were analyzed. The safety criteria, design principles, modeling and simulation methods for arming slider, setback lock, and arming lock are introduced. Air gun testing demonstrates the feasibility of MEMS safe and arm device and the validity of the design method.
The CH4-CO2replacement method to recover CH4from hydrate-bearing sediments has received great attention because it enables the long term storage of CO2and is expected to maintain the stability of gas hydrate-bearing sediments. This paper extends our previous study of the stability of CH4hydrate-bearing sediments to CO2hydrate-bearing sediments to evaluate the safety of the CH4-CO2replacement method. Low temperature, high pressure triaxial compression apparatus was used to measure the mechanical properties of CO2hydrate-bearing sediments. The triaxial tests results for CH4and CO2hydrate-bearing sediments were then compared. It was found that the failure mode of both the CO2and CH4hydrate-bearing sediments was a bulging deformation at mid-height on the samples. Moreover, the stress-strain curves of both the CO2and CH4hydrate-bearing sediments appear to be hyperbolic in shape, and could be divided into three stages: the quasi-elastic stage, the hardening stage and the yield stage. However, the strength of the CO2hydrate-bearing sediments was approximately 15% larger than that of the CH4hydrate-bearing sediments under the same conditions. The results imply that the stability of gas hydrate-bearing sediments could be maintained using the CH4-CO2replacement method to recover CH4from these sediments.
A kind of 5Nm prototype LABLTM (Limited-Angle Brushless Torque Motor) is presented and designed. The basic structure of the motor is deliberated. The method of calculating the electromagnetic torque is provided. The Magnet software is used to optimize some important parameters of the motor. The prototype is fabricated. The test results of the prototype indicate that the LABLTM, with high torque and high reliability, does meet the requirements of direct drive actuator of precision welding equipment. It has a promising future in automatic control, electrical drive, etc.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.