1.Effects of Display Format of Cockpit Air Traffic Information on Conflict Detection Performance
Space Medicine & Medical Engineering 2006;0(02):-
Objective To discuss the display format of cockpit displays of traffic information (CDTI) that would influence the performance of conflict detection at different conditions of temporal and spatial features of air traffic situation.Methods Fifty-four subjects viewed dynamic encounters between own aircraft and three intruder aircrafts with a simulated CDTI.Subjects were asked to estimate potential conflict between intruder and own aircraft.Effects on conflict detection performance were explored with CDTI display format as well as intruder's distance and time to closest point of approach (CPA).The experiment was designed to be three factors measured repeatedly.Results Intruder's distance and time to CPA influenced conflict detection performance when separated display format was adopted to show traffic information.When integrated display format was adopted,the two independent variables before mentioned didn't influence conflict detection performance,and subjects gained high level of conflict detection performance(P
2.A phantom study on the feasibility of recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology in Cyberknife Synchrony-based respiratory tracking
Jing CHEN ; Xianzhi DENG ; Fenfang FU ; Fen ZHENG ; Jianping ZHANG ; Shanting HE ; Benhua XU ; Yaqiang LIU ; Xiaobo LI
Chinese Journal of Radiological Medicine and Protection 2022;42(11):865-870
Objective:To explore the feasibility of recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology in the Cyberknife Synchrony-based respiratory tracking.Methods:CT scans of an inflatable pig lung after anti-rot processing were obtained. Then, eight simulated tumor lesion sites were designed in the left and right lung lobes using intelligent navigation software, with four classified as the sputum bronchial environment group and four classified as the wet bronchial environment group. Based on the implantation principle of Cyberknife fiducial markers, 32 recoverable fiducial markers were implanted around various simulated tumor lesions via bronchus under intelligent guidance. Then, the end-expiratory state of the pig lung was simulated, the pig lung was scanned again to obtain CT images of the implanted recoverable fiducial markers, and the number of successfully implanted fiducial markers was recorded. Eight deliverable Synchrony treatment protocols were designed using the Cyberknife planning system (Multiplan v4.6), and then the pig lung with simulated respiratory movements was exposed to radiation. After radiation, the implanted recoverable fiducial markers were retrieved using the bronchoscopy technique, and the number of successfully retrieved fiducial markers was recorded. Moreover, the translational errors, rotational errors, and rigid body errors were extracted from the Cyberknife log file and analyzed.Results:No recoverable fiducial markers slipped or fell during the experiment. Thirty-two recoverable fiducial markers were successfully implanted and recovered under the guidance of intelligent navigation bronchoscopy, with implantation and recovery success rates of both 100%. Moreover, the tracking rate and rigid body errors of the fiducial markers were 100% and less than 5 mm, respectively. The data from the Cyberknife log file indicated that there was no significant difference between the sputum bronchial environment group and the wet bronchial environment group in the translational errors in the left-right direction, the rotational errors in the roll direction, and the rotational errors in the pitch direction ( P>0.05). Compared to the wet bronchial environment group, the sputum bronchial environment group had slightly higher translational errors in front-back ( Z=-3.57, P<0.01) and cranio-caudal ( Z=-2.53, P<0.05) directions, lower rotational errors along the yaw axis ( Z = -3.88, P < 0.01), and lower rigid body error ( Z=-3.32, P<0.01), and the differences were all statistically significant. Conclusions:The recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology is feasible. Recoverable fiducial markers are stable in the bronchus of the phantom, and the Cyberknife tracking precision can meet clinical requirements. Therefore, the recoverable fiducial marker implantation guided using the intelligent navigation bronchoscopy technology has promising prospects in clinical and teaching applications.