scholarly journals Preliminary evaluation of the VIsion PERformance (VIPER) simulator

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Denise S. Ryan ◽  
Rose K. Sia ◽  
Jennifer B. Eaddy ◽  
Lorie A. Logan ◽  
Jide O. Familoni ◽  
...  
Keyword(s):  
Visual Assessment ◽  
Identification Accuracy ◽  
Visual Performance ◽  
Preliminary Evaluation ◽  
Detection Distance ◽  
Sensitivity Testing ◽  
Road Signs ◽  
The Mean ◽  
Improvised Explosive ◽  
Explosive Devices

Abstract Background This study evaluated the VIsion PERformance (VIPER) simulator’s ability to assess the functional visual performance in warfighters conducting civilian and military tasks. Methods Thirty service members, aged 25–35 years old with a best corrected distance visual acuity (VA) better than or equal to 20/20 or logarithm of the minimum angle of resolution (logMAR) 0.00, were randomized to locate and identify road signs and mock improvised explosive devices (IEDs) under either daytime conditions or with infrared imagery, with (cc) and without (sc) wearing their habitual correction. Participants also underwent binocular uncorrected (UDVA) and corrected (CDVA) visual assessment, refraction, contrast sensitivity testing and wavefront aberrometry. Results The mean age was 28.47 years. The manifest spherical equivalent was − 3.16 ± 1.75 diopters (D), the UDVA in both eyes (OU) was logMAR 0.83 ± 0.47, and the CDVA OU was − 0.11 ± 0.06. For VIPER, the mean difference in the detection distance (DD) for road signs ccDD vs. scDD was 76.7 ± 52.8 m (P < 0.001). The average difference in identification distance (ID) ccID vs. scID was 13.9 ± 6.3 m (P < 0.001). The mean accuracies were 83.5 and 27.9% for cc and sc, respectively (P < 0.001). The regression analysis indicated that a 1.6 m change in the distance accounts for a 1% change in the accuracy (P = 0.002). Without correction, a 4.1 m change accounts for a 1% change in the accuracy (P < 0.001). The average IED ccDD was 29.9 ± 8.2 m, and that for scDD was 13.2 ± 13.6 m (P < 0.001). The average IED ccID was 32.2 ± 6.2 m and that for the scID was 7.4 ± 10.3 m (P < 0.001). The mean IED identification accuracy was 46.7 and 11.4% for cc and sc, respectively (P < 0.001). Conclusions The preliminary results reflect VIPER’s ability to assess functional visual performance when detecting and identifying signs and IEDs. Furthermore, VIPER is able to detect performance changes with and without correction.

Further Investigation of Contrast Sensitivity and Visual Acuity in Pilot Detection of Aircraft

1987 ◽  
Vol 31 (11) ◽  
pp. 1189-1193 ◽  
Author(s):  
Melvin R. O'Neal ◽  
Robert E. Miller
Keyword(s):  
Visual Acuity ◽  
Spatial Frequency ◽  
Contrast Sensitivity ◽  
Weather Conditions ◽  
Detection Performance ◽  
Visual Performance ◽  
Detection Distance ◽  
Cloudy Weather ◽  
The Mean ◽  
Aircraft Detection

Contrast sensitivity (CS) has been reported (Ginsburg et al., 1983) to be strongly related to pilots' aircraft detection performance; however, examination of their results shows a lack of consistency for the CS at any particular spatial frequency to correlate with detection, even for days with similar visibility conditions. To further investigate this relationship, sixty-seven (67) USAF pilots were divided among 8 groups, individually isolated in a bus near the end of a runway on separate days, and detected a T-38 jet aircraft during about 8 landings. CS was measured using the criterion-free two-alternative, temporal forced-choice (2 AFC) technique on the Optronix and with the Vistech VCTS 6500 chart. Visual acuity was assessed at three contrast levels using 3%, 6%, & 85% contrast Regan charts. The mean detection distance of each group ranged from 4.77 to 6.73 miles, and intersubject difference within any group was 0.64 to 2.21 miles. For these partly-cloudy to cloudy weather conditions, neither contrast sensitivity nor visual acuity correlated well with pilot detection of actual aircraft. There was a lack of consistency for the CS at any particular spatial frequency to correlate with detection distance. The best indicator of the pilots with worse detection distances was the performance on the 6% contrast visual acuity chart; with all 5 pilots in the lower 10% of visual performance also being the worst or second worst at aircraft detection in their group.

scholarly journals Modeling and Simulation of Very High Spatial Resolution UXOs and Landmines in a Hyperspectral Scene for UAV Survey

2021 ◽  
Vol 13 (5) ◽  
pp. 837
Author(s):  
Milan Bajić ◽  
Milan Bajić
Keyword(s):  
Modeling And Simulation ◽  
High Spatial Resolution ◽  
Probability Of Detection ◽  
Improvised Explosive Devices ◽  
Full Resolution ◽  
Very High Spatial Resolution ◽  
The Mean ◽  
Improvised Explosive ◽  
Explosive Devices ◽  
Very High

This paper presents methods for the modeling and simulation of explosive target placement in terrain spectral images (i.e., real hyperspectral 90-channel VNIR data), considering unexploded ordnances, landmines, and improvised explosive devices. The models used for landmine detection operate at sub-pixel levels. The presented research uses very fine spatial resolutions, 0.945 × 0.945 mm for targets and 1.868 × 1.868 cm for the scene, where the number of target pixels ranges from 52 to 116. While previous research has used the mean spectral value of the target, it is omitted in this paper. The model considers the probability of detection and its confidence intervals, which are derived and used in the analysis of the considered explosive targets. The detection results are better when decreased target endmembers are used to match the scene resolution, rather than using endmembers at the full resolution of the target. Unmanned aerial vehicles, as carriers of snapshot hyperspectral cameras, enable flexible target resolution selection and good area coverage.

SPECIAL ARTICLE

PEDIATRICS ◽  
1954 ◽  
Vol 14 (5) ◽  
pp. 563-564
Author(s):  
Keyword(s):  
Standard Deviation ◽  
Visual Assessment ◽  
Probable Error ◽  
Oral Examination ◽  
Frequency Curve ◽  
Written Examination ◽  
Lower Figure ◽  
Normal Frequency ◽  
The Mean ◽  
Selection Of

THE WRITTEN examination of January 15, 1954, was taken by 515 candidates, a larger number than in any previous year except 1953 when there were 607 candidates Grades ranged from a lowest mark of 32.0 to a highest mark of 89.5 Inspection of the range resulted in the decision to place the passing mark at 51. On this basis there were 32, or 6.2%, who failed and were therefore ineligible for oral examination. The distribution of the grades earned by the 515 candidates is presented in the form of a histogram. As an aid to visual assessment of the nature of the distribution, a normal frequency curve computed from the mean and standard deviation of the data has been superimposed on the diagram. The distribution of the grades is clearly and impressively skewed to the left, that is, the scores tend to be massed at the high end of the scale and spread out at the low end. An examination of this type is relatively sensitive in the zone of poorer scholarship where the selection of failures is to be made and relatively insensitive in the range of higher scholarship. The intrinsic reliability of the examination has again been assessed by comparing the grade made by each candidate on his odd-numbered questions with that earned on his even-numbered questions. The comparison reveals a "probable error of estimate," P.E.m, of 2.39, a lower figure and therefore a higher degree of reliability than yielded by any previous examination. The Committee is pleased that the increase in reliability was accomplished in spite of the fact that the length of the examination was decreased from 250 grading points in 1953 to 200 grading points.

Peacekeepers suffered combat-related injuries in Mali: a retrospective, descriptive study

2018 ◽  
Vol 166 (3) ◽  
pp. 161-166
Author(s):  
Zhao Yongqiang ◽  
H Dousheng ◽  
L Yanning ◽  
M Xin ◽  
W Kunping
Keyword(s):  
Damage Control ◽  
Damage Control Surgery ◽  
Descriptive Study ◽  
Body Parts ◽  
Medical Treatment Facility ◽  
Chinese Military ◽  
Overseas Operations ◽  
Minor Injuries ◽  
Improvised Explosive ◽  
Explosive Devices

PurposeTo describe the combat-related injuries cured by Chinese Level 2 medical treatment facility (CHN L2) in Mali from 1 March 2016 to 1 March 2018, including type of weapon, mortality, nature of injuries, degree and location of injuries and surgical procedures.Methods A retrospective, descriptive study of 176 injured cases that met the terrorist attacks was conducted. The medical data were collected by an electronic database system. All collected data were entered into an Excel spreadsheet for calculation.ResultsWe found that improvised explosive devices (114/176, 65%) were the most commonly used weapons of attack in Mali. 68.75% of the injuries (121/176) were classified as 'minor injuries according to Abbreviated Injury Scale score. As one patient may suffer multiple injuries, each location and nature of injuries was counted separately. Surface injuries were the top (116/197, 58.88%), followed by orthopaedic injuries (52/197, 26.39%) and internal injuries (29/197, 14.72%). The extremities were the most frequently injured body parts (144/197, 73.09%). We operated 175 surgeries to deal with the 176 combat-related injuries, which accounted for 40.05% of all 437 surgeries. The surgical debridement to remove fragments of explosive was the most frequently performed surgery. We also admitted 20 cases (18/176, 34%) into intensive care unit and transferred 40 cases to Level 3 medical facility.Conclusion Peacekeepers taking protective measures for head and trunk frequently got surface injuries. And their unprotected extremities often got injured. The fragment removal was the top surgery and the damage control surgery was the highly technical nature surgery we performed. Chinese military should offer advanced surgical training course to military surgeons who carry out overseas operations.

Four years of orthopaedic activities in Chinese Role 2 Hospital of eastern Mali peacekeeping area

2018 ◽  
Vol 166 (3) ◽  
pp. 156-160 ◽  
Author(s):  
Dawei Zhang ◽  
Z Li ◽  
X Cao ◽  
B Li
Keyword(s):  
Damage Control ◽  
Damage Control Surgery ◽  
Treatment Facility ◽  
Improvised Explosive Devices ◽  
Skill Sets ◽  
Medical Treatment Facility ◽  
Chinese Military ◽  
Surgical Teams ◽  
Improvised Explosive ◽  
Explosive Devices

IntroductionThe Chinese Role 2 Hospital (CHN-Role 2H) Medical Treatment Facility (MTF) was founded in July 2013 as part of the Chinese commitment to Multidimensional Integrated Stabilization Mission in Mali (MINUSMA). It provides medical care for approximately 5200 personnel of the whole Sector East of MINUSMA including UN military personnel, UN police and UN civilian staff. The aim of this study was to determine the orthopaedic surgical activity over a 4-year period to facilitate the training of future Chinese military surgical teams.Materials and methodsSurgical records of all patients operated on at the CHN-Role 2H between 28 March 2014 to 28 March 2018 were identified, and all orthopaedic activity were analysed.ResultsDuring this period, 1190 patients underwent 2024 surgical procedures. Orthopaedic procedures represented 961/2024 (47.5%) of all the procedures. Battle injury (BI) represented 43% of patients. Improvised explosive devices (IEDs) were responsible for 15.8 % casualties. Fractures (49%) and soft tissue injures (43%) were the most common injuries, with 61% of the fractures being open. Damage control surgery including debridement (23.52%) and external fixation (17.90%) were the most frequently performed interventions.ConclusionOrthopaedic surgery is the most frequently performed surgery in the CHN-Role 2H in Mali. The complexity and severity of injuries demonstrate the urgent need for tailored training and extended skill sets for deploying military orthopaedic surgeons.

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