66 research outputs found

    A Method for Pose and Type Verification of Resistor

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    AbstractThis paper proposes a method for verifying the pose and the type of different resistors mounted on a PCB. First, the pose of the resistor on the PCB is determined and missing resistors are detected by shape_based template matching. Then, the type of the resistor is extracted and compared to the known reference type by edge_based template matching. Finally, six types of resistors have been verified on 120 resistor images. Experiments have shown that the shape_based template can be used to determine the pose of the resistor even if it appears rotated and scaled. The proposed method can achieve the accuracy of 100% and average recognition time of 0.15s

    ProgressLabeller: Visual Data Stream Annotation for Training Object-Centric 3D Perception

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    Visual perception tasks often require vast amounts of labelled data, including 3D poses and image space segmentation masks. The process of creating such training data sets can prove difficult or time-intensive to scale up to efficacy for general use. Consider the task of pose estimation for rigid objects. Deep neural network based approaches have shown good performance when trained on large, public datasets. However, adapting these networks for other novel objects, or fine-tuning existing models for different environments, requires significant time investment to generate newly labelled instances. Towards this end, we propose ProgressLabeller as a method for more efficiently generating large amounts of 6D pose training data from color images sequences for custom scenes in a scalable manner. ProgressLabeller is intended to also support transparent or translucent objects, for which the previous methods based on depth dense reconstruction will fail. We demonstrate the effectiveness of ProgressLabeller by rapidly create a dataset of over 1M samples with which we fine-tune a state-of-the-art pose estimation network in order to markedly improve the downstream robotic grasp success rates. ProgressLabeller is open-source at https://github.com/huijieZH/ProgressLabeller.Comment: IROS 2022 accepted paper; project page: https://progress.eecs.umich.edu/projects/progress-labeller

    Probing the dipole portal to heavy neutral leptons via meson decays at the high-luminosity LHC

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    We consider the dipole portal to sterile neutrinos, also called heavy neutral leptons (HNLs). The dipole interaction with the photon leads to HNL production in meson decays, as well as triggers the HNL decay into an active neutrino and a photon. HNLs with masses of order of 0.01-1 GeV are naturally long-lived if the dipole coupling is sufficiently small. We perform Monte-Carlo simulations and derive the sensitivities of the proposed FASER2 and FACET long-lived particle experiments to HNLs produced via the dipole operator in meson decays at the high-luminosity LHC. Our findings show that these future detectors will be complementary to each other, as well as to existing experiments, and will be able to probe new parts of the parameter space, especially in the case of the dipole operator coupled to the tau neutrino.Comment: 16 pages+refs, 5 figures, 2 table

    TransNet: Transparent Object Manipulation Through Category-Level Pose Estimation

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    Transparent objects present multiple distinct challenges to visual perception systems. First, their lack of distinguishing visual features makes transparent objects harder to detect and localize than opaque objects. Even humans find certain transparent surfaces with little specular reflection or refraction, like glass doors, difficult to perceive. A second challenge is that depth sensors typically used for opaque object perception cannot obtain accurate depth measurements on transparent surfaces due to their unique reflective properties. Stemming from these challenges, we observe that transparent object instances within the same category, such as cups, look more similar to each other than to ordinary opaque objects of that same category. Given this observation, the present paper explores the possibility of category-level transparent object pose estimation rather than instance-level pose estimation. We propose \textit{\textbf{TransNet}}, a two-stage pipeline that estimates category-level transparent object pose using localized depth completion and surface normal estimation. TransNet is evaluated in terms of pose estimation accuracy on a large-scale transparent object dataset and compared to a state-of-the-art category-level pose estimation approach. Results from this comparison demonstrate that TransNet achieves improved pose estimation accuracy on transparent objects. Moreover, we use TransNet to build an autonomous transparent object manipulation system for robotic pick-and-place and pouring tasks

    Biological Monitoring of Cadmium Exposed Workers in a Nickel-Cadmium Battery Factory in China

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    Abstract: Biological Monitoring of Cadmium Exposed Workers in a Nickel-Cadmium Battery Factory in China: Guicheng ZHANG, et al. School of Public Health, Curtin University of Technology-A cross-sectional study of renal damage in workers from a Chinese Ni-Cd battery factory is reported in this paper. The present exposure of surveyed workers to Cd may be likened to that of factories in developed countries prior to the 1950s. The results show urinary cadmium did not increase significantly with the years of exposure in aged workers exposed to cadmium. In these occupationally exposed workers urinary cadmium levels of 3 to 60 µg/g creatinine relate to between 15% and 20% of the workers having B 2 -MG proteinura, and blood cadmium levels less than 5 µg/l relate to more than 10% of the workers having B 2 -MG proteinura. The results suggest that a urinary cadmium concentration of 5 µg/g cr or a blood cadmium concentration of 5 µg/ l would not be a safe level. (J Occup Health 2002; 44: 15-21

    Learning to Select Cuts for Efficient Mixed-Integer Programming

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    Cutting plane methods play a significant role in modern solvers for tackling mixed-integer programming (MIP) problems. Proper selection of cuts would remove infeasible solutions in the early stage, thus largely reducing the computational burden without hurting the solution accuracy. However, the major cut selection approaches heavily rely on heuristics, which strongly depend on the specific problem at hand and thus limit their generalization capability. In this paper, we propose a data-driven and generalizable cut selection approach, named Cut Ranking, in the settings of multiple instance learning. To measure the quality of the candidate cuts, a scoring function, which takes the instance-specific cut features as inputs, is trained and applied in cut ranking and selection. In order to evaluate our method, we conduct extensive experiments on both synthetic datasets and real-world datasets. Compared with commonly used heuristics for cut selection, the learning-based policy has shown to be more effective, and is capable of generalizing over multiple problems with different properties. Cut Ranking has been deployed in an industrial solver for large-scale MIPs. In the online A/B testing of the product planning problems with more than 10710^7 variables and constraints daily, Cut Ranking has achieved the average speedup ratio of 12.42% over the production solver without any accuracy loss of solution.Comment: Paper accepted at Pattern Recognition journa

    The Forward Physics Facility at the High-Luminosity LHC

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    Holographic stability and storage capacity on bulk green-light sensitive TI/PMMA materials

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    An emerging cationic photo-initiator titanocene (TI) dispersed poly (methyl methacrylate) (PMMA) photopolymer was fabricated by an optimized three-step thermo-polymerization method with excellent holographic performances. Materials with different thicknesses (1-3 mm) were prepared and characterized experimentally. The influences of material thickness changes on holographic properties have been investigated in detail. We achieved the response time of 4.98s in 1mm TI/PMMAs, while the cumulative gratings strength of 6.88 and single grating diffraction efficiency of 74% in 3 mm ones. Furthermore, gratings recorded in materials were examined with controlling experimental conditions in a green-light two-beam coupling interference system, under different polarization directions, ambient temperatures and intersection angles, respectively. A better holographic recording condition was proposed. Meanwhile, the influence on recording surroundings for TI/PMMA were analyzed. This work can provide a basis to depict the holographic storage capacity and stability in TI/PMMA polymers

    Small Incision Lenticule Extraction (SMILE) versus Femtosecond Laser-Assisted In Situ Keratomileusis (FS-LASIK) for Myopia: A Systematic Review and Meta-Analysis.

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    The goal of this study was to compare small incision lenticule extraction (SMILE) with femtosecond laser-assisted in situ keratomileusis (FS-LASIK) for treating myopia.The CENTRAL, EMBASE, PubMed databases and a Chinese database (SinoMed) were searched in May of 2016. Twelve studies with 1,076 eyes, which included three randomized controlled trials (RCTs) and nine cohorts, met our inclusion criteria. The overall quality of evidence was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) working group framework. Data were extracted and analysed at three to six months postoperatively. Primary outcome measures included a loss of one or more lines of best spectacle corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA) of 20/20 or better, mean logMAR UCVA, postoperative mean spherical equivalent (SE) and postoperative refraction within ±1.0 D of the target refraction. Secondary outcome measures included ocular surface disease index (OSDI), tear breakup time (TBUT) and Schirmer's 1 test (S1T) as dry eye parameters, along with corneal sensitivity.The overall quality of evidence was considered to be low to very low. Pooled results revealed no significant differences between the two groups with regard to a loss of one or more lines in the BSCVA (OR 1.71; 95% CI: 0.81, 3.63; P = 0.16), UCVA of 20/20 or better (OR 0.71; 95% CI: 0.44, 1.15; P = 0.16), logMAR UCVA (MD 0.00; 95% CI: -0.03, 0.04; P = 0.87), postoperative refractive SE (MD -0.00; 95% CI: -0.05, 0.05; P = 0.97) or postoperative refraction within ±1.0 D of the target refraction (OR 0.78; 95% CI: 0.22, 2.77; P = 0.70) within six months postoperatively. The pooled analysis also indicated that the FS-LASIK group suffered more severely from dry eye symptoms (OSDI; MD -6.68; 95% CI: -11.76, -2.00; P = 0.006) and lower corneal sensitivity (MD 12.40; 95% CI: 10.23, 14.56; P < 0.00001) at six months postoperatively.In conclusion, both FS-LASIK and SMILE are safe, effective and predictable surgical options for treating myopia. However, dry eye symptoms and loss of corneal sensitivity may occur less frequently after SMILE than after FS-LASIK
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