Aims: To investigate the potential risk factors for haemorrhage during suction curettage after uterine artery embolization (UAE) in the treatment of caesarean scar pregnancy (CSP). Methods: A case-control study was executed including 35 patients with CSP and haemorrhage during suction curettage after UAE and 140 controls without haemorrhage. The data collected included gestational age, the distance between the gestational mass and the bladder, and the volume of vaginal bleeding. Results: Six patients with UAE needed blood transfusions and two had a hysterectomy, while no patient in the control group needed these interventions. Multivariate analysis showed that both gestational age and the distance between the gestational mass and the bladder were associated with haemorrhage in the CSP group. The odds ratio (OR) of gestational age between cases and controls was 1.579 (95% confidence interval [CI] 1.291-1.933), and the OR of the distance between the gestational mass and the bladder was 0.208 (95% CI 0.082-0.531). Conclusion: Increased gestational age might be an important risk factor for haemorrhage during suction curettage after UAE in the treatment of patients with CSP, and a distance of >0.2 cm between the gestational mass and the bladder was protective against haemorrhage.

Using diamond saw wire could cut the seabed oil compound pipes. There are different advancing velocities according to the material of pipes; it makes the cutting and advancing velocities under the condition of harmony at the time of cutting the compound pipes underwater. First of all, the experiment system of diamond saw wire was set up by test cistern, equipment of diamond wire saw underwater, hydraulic pressure system, measuring and controlling system, diamond saw wire and single layer seabed oil compound pipes so on. Next, the cutting parameters, which include pipe sizing, working pressure, tensioning force of diamond saw wire, cutting velocity and advancing velocity were initialized and the first experimentation was done. Then, after adjusting the cutting parameters according to the analysis of cutting test, the next cutting experimentation underwater was done. In the end, the wearing capacity of diamond beads was measured and got the optimal advancing velocity which can minish the wearing capacity and prolong the cutting time of diamond beads. So, using these cutting parameters to cut the seabed oil compound pipes validated the feasibility of engineering application.

Subsea Flange Connection Tool (SFCT) is a remote apparatus for connecting underwater bolted flanges, especially applied in the offshore pipeline laying. As a pivotal unit construction of SFCT, Inner-frame enables the Bolt Handling Tool and Nut Handling Tool to move separately in axial direction and together in circumferential direction with the reference of the pipe’s axes. This paper presents the Inner-frame’s structural concept and builds its kinematics-equivalent mechanism models, carrying on the kinematics analysis of Inner-frame; to improve the energy efficiency, models the Inner-frame’s rotation-mechanism parametrically and establishes an objective with the minimum power consumption, which generates the optimal positions for the hinged-hydraulic cylinder’s joints with Box and Pendulum.

In this paper, mechanical model of traditional bellow type pressure compensator is established. The analysis of static characteristic shows that compensation volume and variation of pressure compensate margin are limited to each other. As a result, it cannot meet the requirements of marine equipment to the underwater hydraulic power. Therefore, a new type of pressure compensation unit is developed, it has advantages of big volume compensation and almost constant pressure compensate margin, it solves the core technical problem of deep-water balancing hydraulic power. The simulation results show that this new type of pressure compensator can satisfy the design requirements and improve the working depth of underwater hydraulic systems sharply.

Three-dimensional molecular dynamics simulations are performed to investigate the AFM-based nanometric cutting process of single crystal copper. The effects of cutting velocities (180, 360, and720 m/s) on the cutting force, the ratio of the thrust force and cutting force and subsurface layers. The results show that the dislocations nucleate beneath the tool, and propagate along the [-11-1] direction in the (111) plane. The effects of the nanocutting action from the tool on the subsurface damaged layers decrease gradually as the distance from the tool tip increases. With the increasing cutting speed, the cutting forces increase accordingly. However, the ratio of the the ratio the thrust force and cutting force decrease as the cutting speeds increase. With the proceeding of the cutting process, that tends to the same on the whole.