A framework for real-time compaction guidance system based on compaction priority mapping

Purpose The purpose of this paper is to take advantage of Internet of Things (IoT) for intelligent route programming of crowd emergency evacuation in metro station. It is a novel approach to ensure the crowd safety and reduce the casualties in the emergency context. An evacuation route programming model is constructed to select a suitable evacuation route and support the emergency decision maker of metro station. Design/methodology/approach The IoT technology is employed to collect and screen information, and to construct an expert decision model to support the metro station manager to make decision. As a feasible way to solve the multiple criteria decision-making problem, an improved multi-attributive border approximation area comparison (MABAC) approach is introduced. Findings The case study indicates that the model provides valuable suggestions for evacuation route programming and offers practical support for the design of an evacuation route guidance system. Moreover, IoT plays an important role in the process of intelligent route programming of crowd emergency evacuation in metro station. A library has similar structure and crowd characteristics of a metro station, thus the intelligent route programming approach can be applied to the library crowd evacuation. Originality/value The highlights of this paper are listed as followings: the accuracy and accessibility of the metro station’s real-time information are improved by integrating IoT technology with the intelligent route programming of crowd emergency evacuation. An improved MABAC approach is introduced to the expert support model. It promotes the applicability and reliability of decision making for emergency evacuation route selection in metro station. It is a novel way to combine the decision-making methods with practice.

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Real-Time Image Stabilization Method Based on Optical Flow and Binary Point Feature Matching

Electronics ◽

10.3390/electronics9010198 ◽

2020 ◽

Vol 9 (1) ◽

pp. 198 ◽

Cited By ~ 3

Author(s):

Zilong Deng ◽

Dongxiao Yang ◽

Xiaohu Zhang ◽

Yuguang Dong ◽

Chengbo Liu ◽

...

Keyword(s):

Optical Flow ◽

Real Time ◽

Image Matching ◽

Image Guidance ◽

Feature Matching ◽

Guidance System ◽

Stabilization Method ◽

Image Stabilization ◽

Real Time Image ◽

Time Image

The strap-down missile-borne image guidance system can be easily affected by the unwanted jitters of the motion of the camera, and the subsequent recognition and tracking functions are also influenced, thus severely affecting the navigation accuracy of the image guidance system. So, a real-time image stabilization technology is needed to help improve the image quality of the image guidance system. To satisfy the real-time and accuracy requirements of image stabilization in the strap-down missile-borne image guidance system, an image stabilization method based on optical flow and image matching with binary feature descriptors is proposed. The global motion of consecutive frames is estimated by the pyramid Lucas-Kanade (LK) optical flow algorithm, and the interval frames image matching based on fast retina keypoint (FREAK) algorithm is used to reduce the cumulative trajectory error. A Kalman filter is designed to smooth the trajectory, which is conducive to fitting to the main motion of the guidance system. Simulations have been carried out, and the results show that the proposed algorithm improves the accuracy and real-time performance simultaneously compared to the state-of-art algorithms.

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Real-time computerizedin situ guidance system for ACL graft placement

Computer Aided Surgery ◽

10.1002/igs.10028 ◽

2002 ◽

Vol 7 (1) ◽

pp. 25-40 ◽

Cited By ~ 1

Author(s):

M. Sati ◽

H.-U. St�ubli ◽

Y. Bourquin ◽

M. Kunz ◽

L.-P. Nolte

Keyword(s):

Real Time ◽

Guidance System ◽

Graft Placement ◽

Acl Graft

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A novel 3D guidance system using augmented reality for percutaneous vertebroplasty

Journal of Neurosurgery Spine ◽

10.3171/2013.7.spine12917 ◽

2013 ◽

Vol 19 (4) ◽

pp. 492-501 ◽

Cited By ~ 48

Author(s):

Yuichiro Abe ◽

Shigenobu Sato ◽

Koji Kato ◽

Takahiko Hyakumachi ◽

Yasushi Yanagibashi ◽

...

Keyword(s):

Augmented Reality ◽

Real Time ◽

Sagittal Plane ◽

Percutaneous Vertebroplasty ◽

Axial Plane ◽

Guidance System ◽

Assistive Device ◽

Insertion Angle ◽

Osteoporotic Vertebral Fractures ◽

Needle Trajectory

Augmented reality (AR) is an imaging technology by which virtual objects are overlaid onto images of real objects captured in real time by a tracking camera. This study aimed to introduce a novel AR guidance system called virtual protractor with augmented reality (VIPAR) to visualize a needle trajectory in 3D space during percutaneous vertebroplasty (PVP). The AR system used for this study comprised a head-mount display (HMD) with a tracking camera and a marker sheet. An augmented scene was created by overlaying the preoperatively generated needle trajectory path onto a marker detected on the patient using AR software, thereby providing the surgeon with augmented views in real time through the HMD. The accuracy of the system was evaluated by using a computer-generated simulation model in a spine phantom and also evaluated clinically in 5 patients. In the 40 spine phantom trials, the error of the insertion angle (EIA), defined as the difference between the attempted angle and the insertion angle, was evaluated using 3D CT scanning. Computed tomography analysis of the 40 spine phantom trials showed that the EIA in the axial plane significantly improved when VIPAR was used compared with when it was not used (0.96° ± 0.61° vs 4.34° ± 2.36°, respectively). The same held true for EIA in the sagittal plane (0.61° ± 0.70° vs 2.55° ± 1.93°, respectively). In the clinical evaluation of the AR system, 5 patients with osteoporotic vertebral fractures underwent VIPAR-guided PVP from October 2011 to May 2012. The postoperative EIA was evaluated using CT. The clinical results of the 5 patients showed that the EIA in all 10 needle insertions was 2.09° ± 1.3° in the axial plane and 1.98° ± 1.8° in the sagittal plane. There was no pedicle breach or leakage of polymethylmethacrylate. VIPAR was successfully used to assist in needle insertion during PVP by providing the surgeon with an ideal insertion point and needle trajectory through the HMD. The findings indicate that AR guidance technology can become a useful assistive device during spine surgeries requiring percutaneous procedures.

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