scholarly journals Detection and Imaging of Underground Objects for Distinguishing Explosives by Using a Fluxgate Sensor Array

2019 ◽  
Vol 9 (24) ◽  
pp. 5415 ◽  
Author(s):  
Serkan Gürkan ◽  
Mustafa Karapınar ◽  
Seydi Doğan
Keyword(s):  
Sensor Array ◽  
Experimental Studies ◽  
Field Measurements ◽  
Success Rates ◽  
Fluxgate Sensor ◽  
Sensor Position ◽  
Explosive Properties ◽  
Improvised Explosive ◽  
Explosive Devices ◽  
Data Matrices

Active and passive techniques are two different techniques with which to detect buried explosives. In practice, the most preferred active method works by broadcasting a signal underground. This signal may stimulate the buried explosive and cause it to explode. It is important to eliminate or minimize this drawback to ensure the safety of the detector operator. In this respect, it is important to increase the studies on the passive detection technique which is not currently used in practice. The aim of this study was to passively detect improvised explosive devices without stimulating them, and to classify underground objects as explosive or non-explosive. A fluxgate sensor array having 33 components was used for passive magnetic field measurements, and the nearest neighborhood algorithm was preferred for classifying the resulting data. In experimental studies, 33 different samples having different amounts of ferromagnetic properties were used. Successful imaging and classification were achieved for the measurements up to 20 cm below the surface of soil. Data were recorded as 32 × 25 matrices, and then they were reduced to 32 × 2 matrices having the same features. Samples having explosive properties were distinguished from other underground objects with success rates of 86% and 95% for 32 × 25 and 32 × 2 data matrices, respectively. Classification times for 32 × 25 and 32 × 2 data matrices were 42 ms and 3.62 ms, respectively. For data groups where the best results were obtained for the data matrices, frame numbers classified in one second were calculated as 23.80 and 276.2, respectively. False alarm rate achieved was 5.31%. The experimental results proved the successes of the matrices reduction and classification approach. One of the most common problems encountered in passive detecting techniques is that the sensor position affects the measurements negatively. In this paper, a solution has been proposed for this important problem.

Experimental Investigation Into the Effects of the Steady Wake-Tip Clearance Vortex Interaction in a Compressor Cascade

2015 ◽  
Vol 137 (6) ◽  
Author(s):  
Andreas Krug ◽  
Peter Busse ◽  
Konrad Vogeler
Keyword(s):  
Flow Field ◽  
Experimental Studies ◽  
Axial Compressor ◽  
Field Measurements ◽  
Tip Clearance ◽  
Compressor Cascade ◽  
Unsteady Interaction ◽  
Linear Compressor Cascade ◽  
Tip Clearance Vortex ◽  
The Impact

An important aspect of the aerodynamic flow field in the tip region of axial compressor rotors is the unsteady interaction between the tip clearance vortex (TCV) and the incoming stator wakes. In order to gain an improved understanding of the mechanics involved, systematic studies need to be performed. As a first step toward the characterization of the dynamic effects caused by the relative movement of the blade rows, the impact of a stationary wake-induced inlet disturbance on a linear compressor cascade with tip clearance will be analyzed. The wakes were generated by a fixed grid of cylindrical bars with variable pitch being placed at discrete pitchwise positions. This paper focuses on experimental studies conducted at the newly designed low-speed cascade wind tunnel in Dresden. The general tunnel configuration and details on the specific cascade setup will be presented. Steady state flow field measurements were carried out using five-hole probe traverses up- and downstream of the cascade and accompanied by static wall pressure readings. 2D-particle image velocimetry (PIV) measurements complemented these results by visualizing the blade-to-blade flow field. Hence, the structure of the evolving secondary flow system is evaluated and compared for all tested configurations.

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.

scholarly journals Frequency of Improvised Explosive Devices and Suicide Attempts in the U.S. Army

2017 ◽  
Vol 182 (3) ◽  
pp. e1697-e1703 ◽  
Author(s):  
Robert J. Ursano ◽  
Ronald C. Kessler ◽  
James A. Naifeh ◽  
Holly Herberman Mash ◽  
Carol S. Fullerton ◽  
...  
Keyword(s):  
Suicide Attempts ◽  
Improvised Explosive Devices ◽  
Improvised Explosive ◽  
Explosive Devices ◽  
The U.S
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