In recent years, fringe projection has become an established and essential method for dynamic three-dimensional (3-D) shape measurement in different fields such as online inspection and real-time quality control. Numerous high-speed 3-D shape measurement methods have been developed by either employing high-speed hardware, minimizing the number of pattern projection, or both. However, dynamic 3-D shape measurement of arbitrarily-shaped objects with full sensor resolution without the necessity of additional pattern projections is still a big challenge. In this work, we introduce a high-speed 3-D shape measurement technique based on composite phase-shifting fringes and a multi-view system. The geometry constraint is adopted to search the corresponding points independently without additional images. Meanwhile, by analysing the 3-D position and the main wrapped phase of the corresponding point, pairs with an incorrect 3-D position or a considerable phase difference are effectively rejected. All of the qualified corresponding points are then corrected, and the unique one as well as the related period order is selected through the embedded triangular wave. Finally, considering that some points can only be captured by one of the cameras due to the occlusions, these points may have different fringe orders in the two views, so a left-right consistency check is employed to eliminate those erroneous period orders in this case. Several experiments on both static and dynamic scenes are performed, verifying that our method can achieve a speed of 120 frames per second (fps) with 25-period fringe patterns for fast, dense, and accurate 3-D measurement.
High-speed and high-precision 3D shape measurement plays a central role in diverse applications such as automatic online inspection, robotics control, and human-computer interaction. Conventional multi-frame phase-shifting-based fringe projection profilometry techniques face inherent trade-offs between the speed and measurement precision, which are fundamentally limited by the fringe density and extra pattern projections used for de-ambiguity of fringe orders. Increasing the frequency of the projection fringes can obviously improve the measurement precision; however, it creates difficulties in the subsequent phase unwrapping. For this reason, to date, the frequency of the fringes in typical real-time 3D shape measurement techniques is generally less than 30 to guarantee a reasonable reliability of phase unwrapping. To overcome this limitation, a bi-frequency phase-shifting technique based on a multi-view fringe projection system is proposed, which significantly enhances the measurement precision without compromising the measurement speed. Based on the geometric constraints in a multi-view system, the unwrapped phase of the low-frequency (10-period) fringes can be obtained directly, which serves as a reference to unwrap the high-frequency phase map with a total number of periods of up to 160. Besides, the proposed scheme with 10-period and 160-period fringes is suitable for slightly defocusing projection, allowing a higher projection rate and measurement speed. Experiments on both static and dynamic scenes are performed, verifying that our method can achieve high-speed and high-precision 3D measurement at 300 frames per second with a precision of about 50 μm.
At present, the precise role of human menopausal gonadotropin (HMG) and recombinant luteinizing hormone (rLH) supplementation at an early time of follicular phase on in vitro fertilization (IVF)/intra cytoplasmatic sperm injection (ICSI) outcomes remains uncertain.
Here infertile women of normal ovarian function undergoing their first cycle of IVF/ICSI were studied and were randomly allocated into 3 groups. Group 1, ovarian stimulation with 150IU recombinant follicle-stimulating hormone (FSH) alone. Group 2, patients received 75IU rFSH and 75IU HMG. Group 3 patients were given 150IU rFSH and 75IU rLH.
There were no significant differences in the clinical characteristics, ovarian response, the biochemical, clinical and ongoing pregnancy rates among the 3 groups. No significant differences were found in biochemical, clinical and ongoing pregnancy rates between the patients whose LH levels were lower than 0.75 mIU/ml and those above this threshold in group 1. Furthermore, there were also no significant differences in biochemical, clinical and ongoing pregnancy rates among the 3 group patients whose LH level lower than 0.75 mIU/ml.
The results showed that either the addition of HMG or rLH supplementation at an early time of follicular phase produce no significant benefit on IVF outcome in patients with normal ovarian function.
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.