scholarly journals Automatic body region localization in 3D-CT images based on the improved YOLO model

2022 ◽  
Vol 355 ◽  
pp. 03022
Author(s):  
Linghao Du ◽  
Rui Wang ◽  
Lin Cui ◽  
Xiaolin Min ◽  
Qingyi Liu ◽  
...  

Automatic body region localization in medical three-dimensional (3D)-CT images is a critical step of computerized body-wide Automatic Anatomy Recognition (AAR) system, which can be applied for radiotherapy planning and interest slices retrieving. Currently, the complex internal structure of human body and time consuming computation are the main challenges for the localization. Therefore, this paper introduces and improves the YOLO-v3 model into the body region localization for these problems. First, seven categories of body regions in a CT volume image I are defined based on the modification version of our previous work. Second, an improved YOLO-v3 model is trained to classify each axial slice into one of the seven categories. Then, the effectiveness of the proposed method is evaluated on 3D-CT images that collected from 220 subjects. The experimental results demonstrate that the slice localizing error is less than 3 NoS (Number of slices), which is competitive to the state-of-the-art methods. Beyond this, our method is simple and computationally efficient owing to its less training time, and the average computational time for localizing a volume CT images is about 3 second, which shows potential for a further application.

2018 ◽  
Vol 4 (12) ◽  
pp. eaau6252 ◽  
Author(s):  
Yao Guo ◽  
Weixuan Zhang ◽  
Hanchun Wu ◽  
Junfeng Han ◽  
Yongliang Zhang ◽  
...  

The edges of layered materials have unique properties that substantially differ from the body regions. In this work, we perform a systematic Raman study of the edges of various layered materials (MoS2, WS2, WSe2, PtS2, and black phosphorus). The Raman spectra of the edges feature newly observed forbidden Raman modes, which are originally undetectable from the body region. By selecting the edge type and the polarization directions of the incident and scattered light, all forbidden Raman modes are distinctly detected. Optical simulations show that the edges of layered materials drastically distort the electromagnetic fields of both the incident and scattered light, so that the light interacts with the edges in a distinct way, which differs from its interactions with the body regions.


Author(s):  
Feng Jie Zheng ◽  
Fu Zheng Qu ◽  
Xue Guan Song

Reservoir-pipe-valve (RPV) systems are widely used in many industrial process. The pressure in an RPV system plays an important role in the safe operation of the system, especially during the sudden operation such as rapid valve opening/closing. To investigate the pressure especially the pressure fluctuation in an RPV system, a multidimensional and multiscale model combining the method of characteristics (MOC) and computational fluid dynamics (CFD) method is proposed. In the model, the reservoir is modeled by a zero-dimensional virtual point, the pipe is modeled by a one-dimensional MOC, and the valve is modeled by a three-dimensional CFD model. An interface model is used to connect the multidimensional and multiscale model. Based on the model, a transient simulation of the turbulent flow in an RPV system is conducted, in which not only the pressure fluctuation in the pipe but also the detailed pressure distribution in the valve are obtained. The results show that the proposed model is in good agreement with the full CFD model in both large-scale and small-scale spaces. Moreover, the proposed model is more computationally efficient than the CFD model, which provides a feasibility in the analysis of complex RPV system within an affordable computational time.


2019 ◽  
Vol 141 (5) ◽  
Author(s):  
Feng Jie Zheng ◽  
Chao Yong Zong ◽  
William Dempster ◽  
Fu Zheng Qu ◽  
Xue Guan Song

Reservoir-pipe-valve (RPV) systems are widely used in many industrial processes. The pressure in an RPV system plays an important role in the safe operation of the system, especially during the sudden operations such as rapid valve opening or closing. To investigate the pressure response, with particular interest in the pressure fluctuations in an RPV system, a multidimensional and multiscale model combining the method of characteristics (MOC) and computational fluid dynamics (CFD) method is proposed. In the model, the reservoir is modeled as a zero-dimensional virtual point, the pipe is modeled as a one-dimensional system using the MOC, and the valve is modeled using a three-dimensional CFD model. An interface model is used to connect the multidimensional and multiscale model. Based on the model, a transient simulation of the turbulent flow in an RPV system is conducted in which not only the pressure fluctuation in the pipe but also the detailed pressure distribution in the valve is obtained. The results show that the proposed model is in good agreement when compared with a high fidelity CFD model used to represent both large-scale and small-scale spaces. As expected, the proposed model is significantly more computationally efficient than the CFD model. This demonstrates the feasibility of analyzing complex RPV systems within an affordable computational time.


1999 ◽  
Vol 82 (4) ◽  
pp. 1865-1875 ◽  
Author(s):  
P. Wilson ◽  
P. D. Kitchener ◽  
P. J. Snow

The organization of cutaneous receptive fields in the ventroposterior (VP) thalamus of the common marmosets ( Callithrix jacchus) was determined from single-unit recordings, and these data were correlated with the cytochrome oxidase (CO) histochemistry of the thalamus in the same animals. Under continuously maintained ketamine anesthesia, the receptive fields of a total of 192 single units were recorded from the right VP thalamus using 2 MΩ glass microelectrodes. After the receptive fields were mapped, the brains were reacted for CO histochemistry on 50-μm coronal frozen sections through the entire VP thalamus. The majority of units were localized to the CO-reactive regions that define the medial and lateral divisions of VP (VPm and VPl). Apart from the expected finding of the face being represented in VPm and the body in VPl, reconstructing the electrode tracks and unit locations in the histological sections revealed a general association between discrete regions of CO reactivity and the representation of specific body regions. Some low-threshold cutaneous units were apparently localized to VPi (the CO weak regions dorsal, ventral, and interdigitating with, the CO regions of VP). These VPi units were clearly part of the same representational map as the VPl and VPm units. We conclude that the low-threshold cutaneous receptive fields of the marmoset are organized in a single continuous representation of the contralateral body surface, and that this representation can most simply be interpreted as being folded or crumpled into the three-dimensional space of VP thalamus. The folded nature of the body map in VP may be related to the folded nature of VP as revealed by CO histochemistry.


Radiology ◽  
2011 ◽  
Vol 259 (1) ◽  
pp. 271-277 ◽  
Author(s):  
Kil Joong Kim ◽  
Kyoung Ho Lee ◽  
Bohyoung Kim ◽  
Thomas Richter ◽  
Il Dong Yun ◽  
...  

2015 ◽  
Vol 2015 ◽  
pp. 1-19 ◽  
Author(s):  
Min-Su Park ◽  
Weoncheol Koo

The interaction of water waves with partially porous-surfaced circular cylinders was investigated. A three-dimensional numerical modeling was developed based on the complete mathematical formulation of the eigenfunction expansion method in the potential flow. Darcy’s law was applied to describe the porous boundary. The partial-porous cylinder is composed of a porous-surfaced body near the free surface, and an impermeable-surfaced body with an end-capped rigid bottom below the porous region. The optimal ratio of the porous portion to the impermeable portion can be adopted to design an effective ocean structure with minimal hydrodynamic impact. To scrutinize the hydrodynamic interactions inNpartial-porous circular cylinders, the computational fluid domain is divided into three regions: an exterior region,Ninner porous body regions, andNregions beneath the body. Wave excitation forces and wave run-up on multibodied partial-porous cylinders are calculated and compared for various porous-portion ratios and wave conditions, all of which significantly influence the hydrodynamic property.


2019 ◽  
Vol 12 (20) ◽  
Author(s):  
Cita Nørgård ◽  
Lotte Dyhrberg O’Neill ◽  
John Chemnitz ◽  
Gunver Majgaard

An Augmented Reality (AR) application was developed to help students at SDU to learn the anatomy of the human body (mediastinum). This research project intended to evaluate whether AR strengthened the students’ self-efficacy and motivation, improved learning, and provided a good learning experience. This study focusses on how AR can help students to translate two-dimensional into three-dimensional understanding and evaluates formats of the app (the use of quizzes) together with the didactic design of the teaching sessions with AR. The objectives were to examine A. the effectiveness of using AR on student’s short, long term, and transfer learning outcome compared with traditional teaching, B. the effect of quizzes, and C. app design in relation to didactic design. In the AR world students saw a standardized hologram body combined with selected images from a computed tomography (CT) scan. The CT images were presented at the proper spatial positions in a hologram body. The user could select which structures to be shown at the body (e.g. skin, the vascular system, etc.). They could approach the body, circumvent it, study structures in details and compare the concurrent presentation with the different CT images. During class one group received traditional teaching and two groups studied CT scans in Augmented Reality. One AR-group complemented the AR app with quiz questions and received corrective feedback. The other AR group did not use quiz questions but studied content on their own hand. A teacher was present and ready to help students in all groups. The aim of this paper is to share lessons learned from this intervention and suggest solutions for app design and learning design to facilitate deeper learning processes and scaffold learners’ needs with AR as a learning resource.


2012 ◽  
Vol 53 (1) ◽  
pp. 61-68 ◽  
Author(s):  
Owen D Terreblanche ◽  
Savvas Andronikou ◽  
Linda T Hlabangana ◽  
Taryn Brown ◽  
Pieter E Boshoff

Background There is a heavy reliance on registrars for after-hours CT reporting with a resultant unavoidable error rate. Purpose To determine the after-hours CT reporting error rate by radiology registrars and influencing factors on this error rate. Material and Methods A 2-month prospective study was undertaken at two tertiary, level 1 trauma centers in Johannesburg, South Africa. Provisional CT reports issued by the registrar on call were reviewed by a qualified radiologist the following morning and information relating to the number, time and type of reporting errors made as well as the body region scanned, indication for the scan, year of training of the registrar, and workload during the call were recorded and analyzed. Results A total of 1477 CT scans were performed with an overall error rate of 17.1% and a major error rate of 7.7%. The error rate for 2nd, 3rd, and 4th year registrars was 19.4%, 15.1%, and 14.5%, respectively. A significant difference was found between the error rate in reporting trauma scans (15.8%) compared to non-trauma scans (19.2%) although the difference between emergency scans (16.9%) and elective scans (22.6%) was found to be not significant, a finding likely due to the low number of elective scans performed. Abdominopelvic scans elicited the highest number of errors (33.9%) compared to the other body regions such as head (16.5%) and cervical, thoracic, or lumbar spine (11.7%). Increasing workload resulted in a significant increase in error rate when analyzed with a generalized linear model. There was also a significant difference noted in the time of scan groups which we attributed to a workload effect. Missed findings were the most frequent errors seen (57.3%). Conclusion We found an increasing error rate associated with increasing workload and marked increase in errors with the reporting of abdominopelvic scans. There was a decrease in the error rate when looking an increasing year of training although this there was only found to be significant difference between the 2nd and 3rd year registrars.


Author(s):  
Susan Kotowski ◽  
Kermit Davis ◽  
Michael Jorgensen

As job rotation has become a widely used intervention strategy for the prevention of a wide variety of musculoskeletal disorders, there is a need for the development of assessment techniques that take into account the complexities of multiple body region stressors. The current study investigates the repeatability of a video-based analysis method that combines the exposure measure of four body regions: neck, shoulder, low back, and hand/wrist. Twelve analysts completed the assessment twice for 15 different job rotation schemes. The repeatability was found to be strong (ICC > 0.53) in many of the body regions when individual jobs were evaluated with minimal decrease in repeatability when the entire rotation scheme was considered. Overall, the video-based method provides a potential quick and easy method that will allow for the versatile evaluation needed for practitioners when quantifying exposure for job rotation schemes.


2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Xiangliang Xu ◽  
Shijie Zhao ◽  
Hui Liu ◽  
Zhipeng Sun ◽  
Jianwei Wang ◽  
...  

Objective. To obtain anatomical data of maxillary-zygomatic complex based on simulating the zygomatic implantation using cadaver heads and three-dimensional computerized tomography (3D-CT). Methods. Simulating zygomatic implantation was performed using seven cadaver heads and 3D-CT images from forty-eight adults. After measuring the maxillary-zygomatic complex, we analyzed the position between the implantation path and the maxillary sinus cavity as well as the distance between the implantation path and the zygomatic nerve. Results. The distance from the starting point to the endpoint of the implant was 56.85 ± 5.35 mm in cadaver heads and 58.15 ± 7.37 mm in 3D-CT images. For the most common implantation path (80.20%), the implant went through the maxillary sinus cavity completely. The projecting points of the implant axis (IA) on the surface of zygoma were mainly located in the region of frontal process of zygomatic bone close to the lateral orbital wall. The distances between IA and zygomatic nerve in 53 sides were shorter than 2 mm. Conclusion. The simulating zygomatic implantation on cadaver skulls and 3D-CT imaging provided useful anatomical data of the maxillary-zygomatic complex. It is necessary to take care to avoid the zygomatic nerve injury during implantation, because it frequently appears on the route of implantation.


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