Conformal flight path symbology for head-up displays: Defining the distribution of visual attention in three-dimensional space

Science.gov (United States)

Ververs, Patricia May

An extensive investigation of the format for head-up display (HUD) instrumentation was conducted in a two-part experiment. First, a pilot's information requirements for the tasks of approach, landing, and taxi were determined through a survey administered to professional commercial pilots via the world wide web. The results of the survey were applied in the development of two symbology sets, one set for flight navigation and the second for ground navigation. Second, twenty pilots from the University of Illinois at Urbana-Champaign were recruited to participate in a 3-day experiment. The study was designed to investigate the format for symbology on HUDs and the performance effects of using conformal and partially conformal symbology to support the pilots' tasks. In addition, two different methods were investigated for supporting the pilots' transition between the task of flying and the task of landing. A seamless transition used visual momentum techniques to smoothly guide the pilots' cognitive transition between the serial displays and the associated tasks. A seamed approach employed an abrupt change between the displays to alert the pilots of the task switch. The results indicate that incorporating a virtually conformal, tunnel-in-the-sky symbology into a complete HUD instrumentation set offers promising pilot performance effects. Pilots easily navigated the complex curved approaches with little to no deviation from the flight path (approximately 10 feet), while performing the secondary tasks of the scanning their instruments and the environment. The seamless transition between the flight and ground symbology offered the pilots a preview of the upcoming landing task, thereby preparing them for the task switch. On the ground, the perspective (scene-linked) symbology set supported landing and taxi navigation tasks with the equal efficiency to the plan view display but with much greater precision. Theories of allocation of attention were used to interpret the

Power Measurements for Microvision, Inc., Aircrew Integrated Helmet System Scanning Laser Helmet-Mounted Display

National Research Council Canada - National Science Library

Rash, Clarence

2002-01-01

...) technology based on scanning lasers. Under this program, Microvision, Inc., Bothell, Washington, has developed a scanning laser HMD prototype for use with the Aircrew Integrated Helmet System (AIHS...

Helmet-Mounted Display Design Guide

Science.gov (United States)

1997-11-03

on openStack create menu "CSHMD" set the menuitems of "CSHMD" to "(Main Menu; References;-; Definitions;Display Criteria;Display Formats;Display Modes...34Macintosh" then put ":" into dirSep else put "V’ into dirSep put stackPathO&"Resource"&dirSep into gResPath put 0 into gXRef end openStack on

Binocular Rivalry in Helmet-Mounted Display Applications

Science.gov (United States)

1975-06-01

research apparatus. 31 ., simple magnifying ophthalmic lenses were used, mounted in eyeglass frames. These were 2. 5 diopter lenses for both eyes to...wear eyeglasses with 2. 5 diopter lenses. The focal length of these lenses was 15. 5 inches and the eye waa accommodated at infinity when objects were...HMD luminance is positively related to I-I•D visibility, while ambient scene luminance bears an inverse relation- ship to HMD visibility. Scene

Effects of a Combined 3-D Auditory/visual Cueing System on Visual Target Detection Using a Helmet-Mounted Display

National Research Council Canada - National Science Library

Pinedo, Carlos; Young, Laurence; Esken, Robert

2005-01-01

..., and the development and evaluation of the NDFR symbology for on/off-boresight viewing. The localized auditory research includes looking at the benefits of augmenting the Terrain Collision Avoidance System (TCAS...

Pixels, people, perception, pet peeves, and possibilities: a look at displays

Science.gov (United States)

Task, H. Lee

2007-04-01

This year marks the 35 th anniversary of the Visually Coupled Systems symposium held at Brooks Air Force Base, San Antonio, Texas in November of 1972. This paper uses the proceedings of the 1972 VCS symposium as a guide to address several topics associated primarily with helmet-mounted displays, systems integration and the human-machine interface. Specific topics addressed include monocular and binocular helmet-mounted displays (HMDs), visor projection HMDs, color HMDs, system integration with aircraft windscreens, visual interface issues and others. In addition, this paper also addresses a few mysteries and irritations (pet peeves) collected over the past 35+ years of experience in the display and display related areas.

Latency requirements for head-worn display S/EVS applications

Science.gov (United States)

Bailey, Randall E.; Arthur, Jarvis J., III; Williams, Steven P.

2004-08-01

NASA's Aviation Safety Program, Synthetic Vision Systems Project is conducting research in advanced flight deck concepts, such as Synthetic/Enhanced Vision Systems (S/EVS), for commercial and business aircraft. An emerging thrust in this activity is the development of spatially-integrated, large field-of-regard information display systems. Head-worn or helmet-mounted display systems are being proposed as one method in which to meet this objective. System delays or latencies inherent to spatially-integrated, head-worn displays critically influence the display utility, usability, and acceptability. Research results from three different, yet similar technical areas - flight control, flight simulation, and virtual reality - are collectively assembled in this paper to create a global perspective of delay or latency effects in head-worn or helmet-mounted display systems. Consistent definitions and measurement techniques are proposed herein for universal application and latency requirements for Head-Worn Display S/EVS applications are drafted. Future research areas are defined.

Aircrew helmet design and manufacturing enhancements through the use of advanced technologies

Science.gov (United States)

Cadogan, David P.; George, Alan E.; Winkler, Edward R.

1993-12-01

With the development of helmet mounted displays (HMD) and night vision systems (NVS) for use in military and civil aviation roles, new methods of helmet development need to be explored. The helmet must be designed to provide the user with the most lightweight, form fitting system, while meeting other system performance requirements. This can be achieved through a complete analysis of the system requirements. One such technique for systems analysis, a quality function deployment (QFD) matrix, is explored for this purpose. The advanced helmet development process for developing aircrew helmets includes the utilization of several emerging technologies such as laser scanning, computer aided design (CAD), computer generated patterns from 3-D surfaces, laser cutting of patterns and components, and rapid prototyping (stereolithography). Advanced anthropometry methods for helmet development are also available for use. Besides the application of advanced technologies to be used in the development of helmet assemblies, methods of mass reduction are also discussed. The use of these advanced technologies will minimize errors in the development cycle of the helmet and molds, and should enhance system performance while reducing development time and cost.

The Effects of the Personal Armor System for Ground Troops (PASGT) and the Advanced Combat Helmet (ACH) with and without PVS-14 Night Vision Goggles (NVG) on Neck Biomechanics During Dismounted Soldier Movements

National Research Council Canada - National Science Library

LaFiandra, Michael; Harman, Everett; Cornelius, Nancy; Frykman, Peter; Gutekunst, David; Nelson, Gabe

2007-01-01

Kevlar helmets provide the soldier with basic ballistic and impact protection. However, the helmet has recently become a mounting platform for devices such as night-vision goggles, drop down displays, weapon-aiming systems, etc...

HMD symbol stabilization concepts

Science.gov (United States)

Newman, Richard L.; Greeley, Kevin W.

1995-05-01

Helmet-mounted displays (HMDs) present flight, navigation, and weapon information in the pilot's line of sight. The HMD was developed to allow the pilot to retain aircraft and weapon information while looking off boresight. Symbol stabilization is a key issue for HMDs. In current equipment, the lack of compensation for pilot head motion creates excessive workload during hovering and nap-of-the-earth flight. This high workload translates into excessive training requirements. At the same time, misleading symbology makes interpretation of the height of obstructions impossible. A set of standardized coordinate transformations are necessary for the development of HMD symbology and the control laws. Part of the problem is there is no agreed upon set of definitions or descriptions for how HMD symbols are driven to compensate for pilot head motion. A candidate set of coordinate definitions is proposed to address this issue.

A preliminary study of head-up display assessment techniques. 2: HUD symbology and panel information search time

Science.gov (United States)

Guercio, J. G.; Haines, R. F.

1978-01-01

Twelve commercial pilots were shown 50 high-fidelity slides of a standard aircraft instrument panel with the airspeed, altitude, ADI, VSI, and RMI needles in various realistic orientations. Fifty slides showing an integrated head-up display (HUD) symbology containing an equivalent number of flight parameters as above (with flight path replacing VSI) were also shown. Each subject was told what flight parameter to search for just before each slide was exposed and was given as long as needed (12 sec maximum) to respond by verbalizing the parameter's displayed value. The results for the 100-percent correct data indicated that: there was no significant difference in mean reaction time (averaged across all five flight parameters) between the instrument panel and HUD slides; and a statistically significant difference in mean reaction time was found in responding to different flight parameters.

Binocular Rivalry and Attention in Helmet-Mounted Display Applications

National Research Council Canada - National Science Library

Winterbottom, Marc D; Patterson, Robert; Pierce, Byron J; Covas, Christin; Rogers, Jason

2007-01-01

.... In the present study, we examined whether rivalry suppression could be objectively measured under conditions that simulated a monocular HMD and OTW display, and whether voluntary attention and moving...

Exploring Virtual Worlds With Head-Mounted Displays

Science.gov (United States)

Chung, James C.; Harris, Mark R.; Brooks, Frederick P.; Fuchs, Henry; Kelley, Michael T.; Hughes, John W.; Ouh-Young, Ming; Cheung, Clement; Holloway, Richard L.; Pique, Michael

1989-09-01

For nearly a decade the University of North Carolina at Chapel Hill has been conducting research in the use of simple head-mounted displays in "real-world" applications. Such units provide the user with non-holographic true three-dimensional information, since the kinetic depth effect, stereoscopy, and other visual cues combine to immerse the user in a "virtual world" which behaves like the real world in some respects. UNC's head-mounted display was built inexpensively from commercially available off-the-shelf components. Tracking of the the user's head position and orientation is performed by a Polhemus Navigation Sciences' 3SPACE* tracker. The host computer uses the tracking information to generate updated images corresponding to the user's new left eye and right eye views. The images are broadcast to two liquid crystal television screens (220x320 pixels) mounted on a horizontal shelf at the user's forehead. The user views these color screens through half-silvered mirrors, enabling the computer-generated image to be superimposed upon the user's real physical environment. The head-mounted display has been incorporated into existing molecular modeling and architectural applications being developed at UNC. In molecular structure studies, chemists are presented with a room-sized molecule with which they can interact in a manner more intuitive than that provided by conventional two-dimensional displays and dial boxes. Walking around and through the large molecule may provide quicker understanding of its structure, and such problems as drug-enzyme docking may be approached with greater insight. In architecture, the head-mounted display enables clients to better appreciate three-dimensional designs, which may be misinterpreted in their conventional two-dimensional form by untrained eyes. The addition of a treadmill to the system provides additional kinesthetic input into the understanding of building size and scale.

Head-Mounted Display Technology for Low Vision Rehabilitation and Vision Enhancement

Science.gov (United States)

Ehrlich, Joshua R.; Ojeda, Lauro V.; Wicker, Donna; Day, Sherry; Howson, Ashley; Lakshminarayanan, Vasudevan; Moroi, Sayoko E.

2017-01-01

Purpose To describe the various types of head-mounted display technology, their optical and human factors considerations, and their potential for use in low vision rehabilitation and vision enhancement. Design Expert perspective. Methods An overview of head-mounted display technology by an interdisciplinary team of experts drawing on key literature in the field. Results Head-mounted display technologies can be classified based on their display type and optical design. See-through displays such as retinal projection devices have the greatest potential for use as low vision aids. Devices vary by their relationship to the user’s eyes, field of view, illumination, resolution, color, stereopsis, effect on head motion and user interface. These optical and human factors considerations are important when selecting head-mounted displays for specific applications and patient groups. Conclusions Head-mounted display technologies may offer advantages over conventional low vision aids. Future research should compare head-mounted displays to commonly prescribed low vision aids in order to compare their effectiveness in addressing the impairments and rehabilitation goals of diverse patient populations. PMID:28048975

Helmet blastometer

Energy Technology Data Exchange (ETDEWEB)

Moss, William C; King, Michael J

2015-03-24

A helmet blastometer for characterizing the direction, speed, magnitude, and duration of a blast event to determine the likelihood of blast-induced traumatic brain injury (biTBI). Time of arrival (TOA) gage sensors are mounted on a rigid outer shell of the helmet each producing a TOA signal in response to a fast rising blast induced positive pressure change above a predetermined threshold. A receiver analyzes the positive pressure changes from the gages to determine direction, speed, and magnitude of a blast. Other TOA gauge sensors can be used to produce a TOA signal in response to a negative pressure change below a predetermined threshold. The positive and negative pressure change TOA signals are used to determine blast duration. A second set of internal contact pressure sensors is connected to an inner liner of the helmet to detect contact pressure on a user's head to determine if biTBI has been sustained.

The effects of dynamic friction in oblique motorcycle helmet impacts

Science.gov (United States)

Bonugli, Enrique

The purpose of this study was to determine the frictional properties between the exterior surface of a motorcycle helmet and 'typical' roadway surfaces. These values were compared to abrasive papers currently recommended by government helmet safety standards and widely used by researchers in the field of oblique motorcycle helmet impacts. A guided freefall test fixture was utilized to obtain nominal impact velocities of 5, 7 and 9 m/s. The impacting surfaces were mounted to an angled anvil to simulate off-centered oblique collision. Head accelerations and impact forces were measured for each test. Analysis of the normal and tangential forces imparted to the contact surface indicated that the frictional properties of abrasive papers differ from asphalt and cement in magnitude, duration and onset. Reduction in head acceleration, both linear and angular, were observed when asphalt and cement were used as the impacting surface. Roofing shingle was determined to be a more suitable material to simulate 'typical' roadway surfaces however, this may not be ideal for use in a controlled laboratory setting. In a laboratory setting, the author recommends cement as a best-fit material to simulate roadway surface for use in oblique motorcycle helmet impacts since this material displayed characteristics that closely resemble asphalt and is currently used as a roadway construction material.

System Would Generate Virtual Heads-Up Display

Science.gov (United States)

Lambert, James L.

1994-01-01

Proposed helmet-mounted electronic display system superimposes full-color alphanumerical and/or graphical information onto observer's visual field. Displayed information projected directly onto observer's retinas, giving observer illusion of full-size computer display in foreground or background. Display stereoscopic, holographic, or in form of virtual image. Used by pilots to view navigational information while looking outside or at instruments, by security officers to view information about critical facilities while looking at visitors, or possibly even stock-exchange facilities to view desktop monitors and overhead displays simultaneously. System includes acousto-optical tunable filter (AOTF), which acts as both spectral filter and spatial light modulator.

Performance Benefits with Scene-Linked HUD Symbology: An Attentional Phenomenon?

Science.gov (United States)

Levy, Jonathan L.; Foyle, David C.; McCann, Robert S.; Null, Cynthia H. (Technical Monitor)

1999-01-01

Previous research has shown that in a simulated flight task, navigating a path defined by ground markers while maintaining a target altitude is more accurate when an altitude indicator appears in a virtual "scenelinked" format (projected symbology moving as if it were part of the out-the-window environment) compared to the fixed-location, superimposed format found on present-day HUDs (Foyle, McCann & Shelden, 1995). One explanation of the scene-linked performance advantage is that attention can be divided between scene-linked symbology and the outside world more efficiently than between standard (fixed-position) HUD symbology and the outside world. The present study tested two alternative explanations by manipulating the location of the scene-linked HUD symbology relative to the ground path markers. Scene-linked symbology yielded better ground path-following performance than standard fixed-location superimposed symbology regardless of whether the scene-linked symbology appeared directly along the ground path or at various distances off the path. The results support the explanation that the performance benefits found with scene-linked symbology are attentional.

Helmet-based physiological signal monitoring system.

Science.gov (United States)

Kim, Youn Sung; Baek, Hyun Jae; Kim, Jung Soo; Lee, Haet Bit; Choi, Jong Min; Park, Kwang Suk

2009-02-01

A helmet-based system that was able to monitor the drowsiness of a soldier was developed. The helmet system monitored the electrocardiogram, electrooculogram and electroencephalogram (alpha waves) without constraints. Six dry electrodes were mounted at five locations on the helmet: both temporal sides, forehead region and upper and lower jaw strips. The electrodes were connected to an amplifier that transferred signals to a laptop computer via Bluetooth wireless communication. The system was validated by comparing the signal quality with conventional recording methods. Data were acquired from three healthy male volunteers for 12 min twice a day whilst they were sitting in a chair wearing the sensor-installed helmet. Experimental results showed that physiological signals for the helmet user were measured with acceptable quality without any intrusions on physical activities. The helmet system discriminated between the alert and drowsiness states by detecting blinking and heart rate variability (HRV) parameters extracted from ECG. Blinking duration and eye reopening time were increased during the sleepiness state compared to the alert state. Also, positive peak values of the sleepiness state were much higher, and the negative peaks were much lower than that of the alert state. The LF/HF ratio also decreased during drowsiness. This study shows the feasibility for using this helmet system: the subjects' health status and mental states could be monitored without constraints whilst they were working.

Creating Gaze Annotations in Head Mounted Displays

DEFF Research Database (Denmark)

Mardanbeigi, Diako; Qvarfordt, Pernilla

2015-01-01

To facilitate distributed communication in mobile settings, we developed GazeNote for creating and sharing gaze annotations in head mounted displays (HMDs). With gaze annotations it possible to point out objects of interest within an image and add a verbal description. To create an annota- tion...

Instrument-mounted displays for reducing cognitive load during surgical navigation.

Science.gov (United States)

Herrlich, Marc; Tavakol, Parnian; Black, David; Wenig, Dirk; Rieder, Christian; Malaka, Rainer; Kikinis, Ron

2017-09-01

Surgical navigation systems rely on a monitor placed in the operating room to relay information. Optimal monitor placement can be challenging in crowded rooms, and it is often not possible to place the monitor directly beside the situs. The operator must split attention between the navigation system and the situs. We present an approach for needle-based interventions to provide navigational feedback directly on the instrument and close to the situs by mounting a small display onto the needle. By mounting a small and lightweight smartwatch display directly onto the instrument, we are able to provide navigational guidance close to the situs and directly in the operator's field of view, thereby reducing the need to switch the focus of view between the situs and the navigation system. We devise a specific variant of the established crosshair metaphor suitable for the very limited screen space. We conduct an empirical user study comparing our approach to using a monitor and a combination of both. Results from the empirical user study show significant benefits for cognitive load, user preference, and general usability for the instrument-mounted display, while achieving the same level of performance in terms of time and accuracy compared to using a monitor. We successfully demonstrate the feasibility of our approach and potential benefits. With ongoing technological advancements, instrument-mounted displays might complement standard monitor setups for surgical navigation in order to lower cognitive demands and for improved usability of such systems.

The research on a novel type of the solar-blind UV head-mounted displays

Science.gov (United States)

Zhao, Shun-long

2011-08-01

Ultraviolet technology of detecting is playing a more and more important role in the field of civil application, especially in the corona discharge detection, in modern society. Now the UV imaging detector is one of the most important equipments in power equipment flaws detection. And the modern head-mounted displays (HMDs) have shown the applications in the fields of military, industry production, medical treatment, entertainment, 3D visualization, education and training. We applied the system of head-mounted displays to the UV image detection, and a novel type of head-mounted displays is presented: the solar-blind UV head-mounted displays. And the structure is given. By the solar-blind UV head-mounted displays, a real-time, isometric and visible image of the corona discharge is correctly displayed upon the background scene where it exists. The user will see the visible image of the corona discharge on the real scene rather than on a small screen. Then the user can easily find out the power equipment flaws and repair them. Compared with the traditional UV imaging detector, the introducing of the HMDs simplifies the structure of the whole system. The original visible spectrum optical system is replaced by the eye in the solar-blind UV head-mounted displays. And the optical image fusion technology would be used rather than the digital image fusion system which is necessary in traditional UV imaging detector. That means the visible spectrum optical system and digital image fusion system are not necessary. This makes the whole system cheaper than the traditional UV imaging detector. Another advantage of the solar-blind UV head-mounted displays is that the two hands of user will be free. So while observing the corona discharge the user can do some things about it. Therefore the solar-blind UV head-mounted displays can make the corona discharge expose itself to the user in a better way, and it will play an important role in corona detection in the future.

Clinical application of a modern high-definition head-mounted display in sonography.

Science.gov (United States)

Takeshita, Hideki; Kihara, Kazunori; Yoshida, Soichiro; Higuchi, Saori; Ito, Masaya; Nakanishi, Yasukazu; Kijima, Toshiki; Ishioka, Junichiro; Matsuoka, Yoh; Numao, Noboru; Saito, Kazutaka; Fujii, Yasuhisa

2014-08-01

Because of the remarkably improved image quality and wearability of modern head-mounted displays, a monitoring system using a head-mounted display rather than a fixed-site monitor for sonographic scanning has the potential to improve the diagnostic performance and lessen the examiner's physical burden during a sonographic examination. In a preclinical setting, 2 head-mounted displays, the HMZ-T2 (Sony Corporation, Tokyo, Japan) and the Wrap1200 (Vuzix Corporation, Rochester, NY), were found to be applicable to sonography. In a clinical setting, the feasibility of the HMZ-T2 was shown by its good image quality and acceptable wearability. This modern device is appropriate for clinical use in sonography. © 2014 by the American Institute of Ultrasound in Medicine.

Light Field Rendering for Head Mounted Displays using Pixel Reprojection

DEFF Research Database (Denmark)

Hansen, Anne Juhler; Klein, Jákup; Kraus, Martin

2017-01-01

Light field displays have advantages over traditional stereoscopic head mounted displays, for example, because they can overcome the vergence-accommodation conflict. However, rendering light fields can be a heavy task for computers due to the number of images that have to be rendered. Since much ...

Motorcycle helmets in Vietnam: ownership, quality, purchase price, and affordability.

Science.gov (United States)

Hung, Dang Viet; Stevenson, Mark R; Ivers, Rebecca Q

2008-06-01

This study investigated motorcycle helmet ownership, quality, purchase price, and affordability in Vietnam. A random sample of motorcyclists was interviewed to investigate aspects of helmet ownership, the purchase price, and affordability of a motorcycle helmet. Multivariate modeling conducted to determine factors associated with the purchase price and affordability of motorcycle helmets. Helmet quality was assessed based on current legal requirements in Vietnam. The prevalence of helmet use in Vietnam remains low (23.3%) despite a high level of helmet ownership (94%), indicating that this is an important area for public health intervention. Overall the quality of helmets appeared to be good; however, few helmets displayed legally required information. Motorcyclists with a high income purchase more helmets for their household rather than more expensive helmets. To ensure that helmets are accessible to the community, policy-makers need to consider pricing motorcycle helmets at a price indicated by the results of this study. Prior to universal motorcycle helmet legislation, the government will also need to ensure that standard helmets are available and that enforcement is at a level to ensure that motorcycle helmets are actually used.

Use cases and usability challenges for head-mounted displays in healthcare

Directory of Open Access Journals (Sweden)

Mentler T.

2015-09-01

Full Text Available In the healthcare domain, head-mounted displays (HMDs with augmented reality (AR modalities have been reconsidered for application as a result of commercially available products and the needs for using computers in mobile context. Within a user-centered design approach, interviews were conducted with physicians, nursing staff and members of emergency medical services. Additionally practitioners were involved in evaluating two different head-mounted displays. Based on these measures, use cases and usability considerations according to interaction design and information visualization were derived and are described in this contribution.

Psychometric Assessment of Stereoscopic Head-Mounted Displays

Science.gov (United States)

2016-06-29

Journal Article 3. DATES COVERED (From – To) Jan 2015 - Dec 2015 4. TITLE AND SUBTITLE PSYCHOMETRIC ASSESSMENT OF STEREOSCOPIC HEAD- MOUNTED DISPLAYS...to render an immersive three-dimensional constructive environment. The purpose of this effort was to quantify the impact of aircrew vision on an...simulated tasks requiring precise depth discrimination. This work will provide an example validation method for future stereoscopic virtual immersive

Pilot stereotypes for navigation symbols on electronic displays

Science.gov (United States)

2006-09-20

There is currently no common symbology standard for the : electronic display of navigation information. The wide : range of display technologies and the different functions : these displays support make it difficult to design symbols : that are easil...

A novel approach to patient self-monitoring of sonographic examinations using a head-mounted display.

Science.gov (United States)

Inoue, Masaharu; Kihara, Kazunori; Yoshida, Soichiro; Ito, Masaya; Takeshita, Hideki; Ishioka, Junichiro; Matsuoka, Yoh; Numao, Noboru; Saito, Kazutaka; Fujii, Yasuhisa

2015-01-01

Patients' use of a head-mounted display during their sonographic examinations could provide them with information about their diseases in real time and might help improve "patient-centered care." We conducted this prospective study to evaluate the feasibility of a modern head-mounted display for patient self-monitoring of sonographic examinations. In November and December 2013, 58 patients were enrolled. Patients wore a head-mounted display (HMZ-T2; Sony Corporation, Tokyo, Japan) during their sonographic examinations and watched their own images in real time. After the sonographic examinations, the patients completed a questionnaire, in which they evaluated the utility of the head-mounted display, their understanding of their diseases, their satisfaction with using the head-mounted display, and any adverse events. Until November 26, 2013, patients' names were requested on the questionnaire; after that date, the questionnaire was changed to be anonymous. Of the 58 patients, 56 (97%) elected to participate in this study. The head-mounted display was reported to have good image quality by 42 patients (75%) and good wearability by 39 (70%). Thirty-six patients (64%) reported they had deepened their understanding of their diseases. There were no major complications, and only 2 patients (4%) had mild eye fatigue. There was no significant association between questionnaire results and patient characteristics. None of the questionnaire results changed significantly after the questionnaire was made anonymous. The use of a modern head-mounted display by patients during sonographic examinations provided good image quality with acceptable wearability. It could deepen their understanding of their diseases and help develop patient-centered care. © 2015 by the American Institute of Ultrasound in Medicine.

Exploring geovisualization symbology for landscape genetics

DEFF Research Database (Denmark)

Aoidh, Eoin Mac; Martinsohn, Jann Th.; Maes, Gregory E.

2013-01-01

or genetic expertise. While specialist applications exist, alternative accessible solutions do not provide adequate support for the visualization of multi‐attribute spatially referenced genetic population structure information. As a solution, we document our exploration for an appropriate symbology...... to communicate landscape genetic information through an accessible, web‐based interface. A full problem description, review of available technologies, development rationale, and discussion of the symbology exploration are provided.......Landscape genetics, which considers genetic population structure in the context of spatially referenced parameters in the surrounding landscape, has been shown to be extremely useful for wildlife management. Unfortunately its widespread uptake beyond the research community is hampered due to a lack...

Preliminary study of ergonomic behavior during simulated ultrasound-guided regional anesthesia using a head-mounted display.

Science.gov (United States)

Udani, Ankeet D; Harrison, T Kyle; Howard, Steven K; Kim, T Edward; Brock-Utne, John G; Gaba, David M; Mariano, Edward R

2012-08-01

A head-mounted display provides continuous real-time imaging within the practitioner's visual field. We evaluated the feasibility of using head-mounted display technology to improve ergonomics in ultrasound-guided regional anesthesia in a simulated environment. Two anesthesiologists performed an equal number of ultrasound-guided popliteal-sciatic nerve blocks using the head-mounted display on a porcine hindquarter, and an independent observer assessed each practitioner's ergonomics (eg, head turning, arching, eye movements, and needle manipulation) and the overall block quality based on the injectate spread around the target nerve for each procedure. Both practitioners performed their procedures without directly viewing the ultrasound monitor, and neither practitioner showed poor ergonomic behavior. Head-mounted display technology may offer potential advantages during ultrasound-guided regional anesthesia.

Immersive vision assisted remote teleoperation using head mounted displays

International Nuclear Information System (INIS)

Vakkapatla, Veerendrababu; Singh, Ashutosh Pratap; Rakesh, V.; Rajagopalan, C.; Murugan, S.; Sai Baba, M.

2016-01-01

Handling and inspection of irradiated material is inevitable in nuclear industry. Hot cells are shielded radiation containment chambers equipped with master slave manipulators that facilitates remote handling. The existing methods using viewing windows and cameras for viewing the contents of hot cell to manipulate the radioactive elements have problems such as optical distortion, limited distance teleoperation, limited field of view that lead to inefficient operation. This paper presents a method of achieving immersive teleoperation to operate the master slave manipulator in hot cells by exploiting the advanced tracking and display capabilities of head mounted display devices. (author)

Exaggerated displays do not improve mounting success in male seaweed flies Fucellia tergina (Diptera: Anthomyiidae).

Science.gov (United States)

Memmott, Ruth; Briffa, Mark

2015-11-01

Signals of individual quality are assumed to be difficult to exaggerate, either because they are directly linked to underlying traits (indices) or because they are costly to perform (handicaps). In practise advertisement displays may consist of conventional and costly components, for instance where a morphological structure related to body size is used in visual displays. In this case, there is the potential for dishonest displays, due to the population level variance around the relationship between body size and display structures. We examine the use of wing flicking displays that we observed in situ in a strandline dwelling seaweed fly Fucellia tergina, using overall body size and the size of their eyes as underlying indicators of condition. Males displayed far more frequently than females, and were also observed to frequently mount other flies, a behaviour that was rare in females. The rate of display was greater for males that had positive residual values from relationships between wing length and body length. In other words those males with larger than expected wings for their underlying quality displayed more frequently, indicating that these displays are open to exaggeration. Males with larger than expected wings (for the size of their body or eyes), however, mounted less frequently. We suggest that small bodied males are less successful in terms of mounting, but that those small males with relatively large wings may attempt to compensate for this through increased display effort. Copyright © 2015 Elsevier B.V. All rights reserved.

Nano-Composite Foam Sensor System in Football Helmets.

Science.gov (United States)

Merrell, A Jake; Christensen, William F; Seeley, Matthew K; Bowden, Anton E; Fullwood, David T

2017-12-01

American football has both the highest rate of concussion incidences as well as the highest number of concussions of all contact sports due to both the number of athletes and nature of the sport. Recent research has linked concussions with long term health complications such as chronic traumatic encephalopathy and early onset Alzheimer's. Understanding the mechanical characteristics of concussive impacts is critical to help protect athletes from these debilitating diseases and is now possible using helmet-based sensor systems. To date, real time on-field measurement of head impacts has been almost exclusively measured by devices that rely on accelerometers or gyroscopes attached to the player's helmet, or embedded in a mouth guard. These systems monitor motion of the head or helmet, but do not directly measure impact energy. This paper evaluates the accuracy of a novel, multifunctional foam-based sensor that replaces a portion of the helmet foam to measure impact. All modified helmets were tested using a National Operating Committee Standards for Athletic Equipment-style drop tower with a total of 24 drop tests (4 locations with 6 impact energies). The impacts were evaluated using a headform, instrumented with a tri-axial accelerometer, mounted to a Hybrid III neck assembly. The resultant accelerations were evaluated for both the peak acceleration and the severity indices. These data were then compared to the voltage response from multiple Nano Composite Foam sensors located throughout the helmet. The foam sensor system proved to be accurate in measuring both the HIC and Gadd severity index, as well as peak acceleration while also providing additional details that were previously difficult to obtain, such as impact energy.

Tackling the challenges of fully immersive head-mounted AR devices

Science.gov (United States)

Singer, Wolfgang; Hillenbrand, Matthias; Münz, Holger

2017-11-01

The optical requirements of fully immersive head mounted AR devices are inherently determined by the human visual system. The etendue of the visual system is large. As a consequence, the requirements for fully immersive head-mounted AR devices exceeds almost any high end optical system. Two promising solutions to achieve the large etendue and their challenges are discussed. Head-mounted augmented reality devices have been developed for decades - mostly for application within aircrafts and in combination with a heavy and bulky helmet. The established head-up displays for applications within automotive vehicles typically utilize similar techniques. Recently, there is the vision of eyeglasses with included augmentation, offering a large field of view, and being unobtrusively all-day wearable. There seems to be no simple solution to reach the functional performance requirements. Known technical solutions paths seem to be a dead-end, and some seem to offer promising perspectives, however with severe limitations. As an alternative, unobtrusively all-day wearable devices with a significantly smaller field of view are already possible.

Recent advances in head-mounted light field displays for virtual and augmented reality (Conference Presentation)

Science.gov (United States)

Hua, Hong

2017-02-01

Head-mounted light field displays render a true 3D scene by sampling either the projections of the 3D scene at different depths or the directions of the light rays apparently emitted by the 3D scene and viewed from different eye positions. They are capable of rendering correct or nearly correct focus cues and addressing the very well-known vergence-accommodation mismatch problem in conventional virtual and augmented reality displays. In this talk, I will focus on reviewing recent advancements of head-mounted light field displays for VR and AR applications. I will demonstrate examples of HMD systems developed in my group.

Noise-Canceling Helmet Audio System

Science.gov (United States)

Seibert, Marc A.; Culotta, Anthony J.

2007-01-01

A prototype helmet audio system has been developed to improve voice communication for the wearer in a noisy environment. The system was originally intended to be used in a space suit, wherein noise generated by airflow of the spacesuit life-support system can make it difficult for remote listeners to understand the astronaut s speech and can interfere with the astronaut s attempt to issue vocal commands to a voice-controlled robot. The system could be adapted to terrestrial use in helmets of protective suits that are typically worn in noisy settings: examples include biohazard, fire, rescue, and diving suits. The system (see figure) includes an array of microphones and small loudspeakers mounted at fixed positions in a helmet, amplifiers and signal-routing circuitry, and a commercial digital signal processor (DSP). Notwithstanding the fixed positions of the microphones and loudspeakers, the system can accommodate itself to any normal motion of the wearer s head within the helmet. The system operates in conjunction with a radio transceiver. An audio signal arriving via the transceiver intended to be heard by the wearer is adjusted in volume and otherwise conditioned and sent to the loudspeakers. The wearer s speech is collected by the microphones, the outputs of which are logically combined (phased) so as to form a microphone- array directional sensitivity pattern that discriminates in favor of sounds coming from vicinity of the wearer s mouth and against sounds coming from elsewhere. In the DSP, digitized samples of the microphone outputs are processed to filter out airflow noise and to eliminate feedback from the loudspeakers to the microphones. The resulting conditioned version of the wearer s speech signal is sent to the transceiver.

Neck muscle strain when wearing helmet and NVG during acceleration on a trampoline.

Science.gov (United States)

Sovelius, Roope; Oksa, Juha; Rintala, Harri; Huhtala, Heini; Siitonen, Simo

2008-02-01

The helmet-mounted equipment worn by military pilots increases the weight of the helmet system and shifts its center of gravity, increasing the loads on neck structures, especially during acceleration. The aim of this study was to determine neck muscle strain with different head-loads during trampoline-induced G loads (0 to +4 G). Under three conditions [no helmet, helmet, helmet with night vision goggles (NVG)], 14 subjects performed trampoline exercises including basic, hand-and-knee, and back bouncing. EMG activity was measured for the sternocleidomastoid (SCM), cervical erector spinae (CES), trapezoid (TRA), and thoracic erector spinae (TES) muscles. Muscle strain was determined as a percentage of maximal voluntary contraction (%MVC). For the three exercises combined, the following significant changes were found: compared to control, the helmet increased muscle strain by 18%, 28%, and 18% in the SCM, CES, and TRA, respectively; NVG produced a further increase of 11% in the SCM and 6% in the CES. During back bouncing, the helmet increased muscle strain by 14% in the SCM and 19% in the CES, and NVG further increased this strain by 14% in the SCM. Hand-and-knee bouncing loaded extensors: the helmet caused increases of 46% in the CES and 29% in the TES, while NVG produced a further 13% increase in CES activation. Helmet weight alone had a large effect on muscular workload. The additional frontal weight of the NVG caused a further increase in the activity of cervical muscles that were already subjected to high strain.

A head-mounted display system for augmented reality: Initial evaluation for interventional MRI

International Nuclear Information System (INIS)

Wendt, M.; Wacker, F.K.

2003-01-01

Purpose: To discuss the technical details of a head mounted display with an augmented reality (AR) system and to describe a first pre-clinical evaluation in interventional MRI. Method: The AR system consists of a video-see-through head mounted display (HMD), mounted with a mini video camera for tracking and a stereo pair of mini cameras that capture live images of the scene. The live video view of the phantom/patient is augmented with graphical representations of anatomical structures from MRI image data and is displayed on the HMD. The application of the AR system with interventional MRI was tested using a MRI data set of the head and a head phantom. Results: The HMD enables the user to move around and observe the scene dynamically from various viewpoints. Within a short time the natural hand-eye coordination can easily be adapted to the slightly different view. The 3D perception is based on stereo and kinetic depth cues. A circular target with a diameter of 0.5 square centimeter was hit in 19 of 20 attempts. In a first evaluation the MRI image data augmented reality scene of a head phantom allowed good planning and precise simulation of a puncture. Conclusion: The HMD in combination with AR provides a direct, intuitive guidance for interventional MR procedures. (orig.) [de

Designing and evaluating symbols for electronic displays of navigation information : symbol stereotypes and symbol-feature rules

Science.gov (United States)

2005-09-30

There is currently no common symbology standard for the electronic display of navigation information. The wide range of display technology and the different functions these displays support makes it difficult to design symbols that are easily recogni...

Helmet-Mounted Displays: Sensation, Perception and Cognition Issues

Science.gov (United States)

2009-01-01

bagels, pretzels, fig or fruit bars, granola bars, yogurt , milk, fresh fruits and vegetables. The bottom line on nutrition and combat is to eat sensible...carcinogens in tobacco are the tobacco-specific nitrosamines. They are formed during the growing, curing, fermenting , and aging of tobacco. Other

Heads-Up Display with Virtual Precision Approach Path Indicator as Implemented in a Real-Time Piloted Lifting-Body Simulation

Science.gov (United States)

Neuhaus, Jason R.

2018-01-01

This document describes the heads-up display (HUD) used in a piloted lifting-body entry, approach and landing simulation developed for the simulator facilities of the Simulation Development and Analysis Branch (SDAB) at NASA Langley Research Center. The HUD symbology originated with the piloted simulation evaluations of the HL-20 lifting body concept conducted in 1989 at NASA Langley. The original symbology was roughly based on Shuttle HUD symbology, as interpreted by Langley researchers. This document focuses on the addition of the precision approach path indicator (PAPI) lights to the HUD overlay.

Comparison of optical see-through head-mounted displays for surgical interventions with object-anchored 2D-display.

Science.gov (United States)

Qian, Long; Barthel, Alexander; Johnson, Alex; Osgood, Greg; Kazanzides, Peter; Navab, Nassir; Fuerst, Bernhard

2017-06-01

Optical see-through head-mounted displays (OST-HMD) feature an unhindered and instantaneous view of the surgery site and can enable a mixed reality experience for surgeons during procedures. In this paper, we present a systematic approach to identify the criteria for evaluation of OST-HMD technologies for specific clinical scenarios, which benefit from using an object-anchored 2D-display visualizing medical information. Criteria for evaluating the performance of OST-HMDs for visualization of medical information and its usage are identified and proposed. These include text readability, contrast perception, task load, frame rate, and system lag. We choose to compare three commercially available OST-HMDs, which are representatives of currently available head-mounted display technologies. A multi-user study and an offline experiment are conducted to evaluate their performance. Statistical analysis demonstrates that Microsoft HoloLens performs best among the three tested OST-HMDs, in terms of contrast perception, task load, and frame rate, while ODG R-7 offers similar text readability. The integration of indoor localization and fiducial tracking on the HoloLens provides significantly less system lag in a relatively motionless scenario. With ever more OST-HMDs appearing on the market, the proposed criteria could be used in the evaluation of their suitability for mixed reality surgical intervention. Currently, Microsoft HoloLens may be more suitable than ODG R-7 and Epson Moverio BT-200 for clinical usability in terms of the evaluated criteria. To the best of our knowledge, this is the first paper that presents a methodology and conducts experiments to evaluate and compare OST-HMDs for their use as object-anchored 2D-display during interventions.

Flat-panel video resolution LED display system

Science.gov (United States)

Wareberg, P. G.; Kennedy, D. I.

The system consists of a 128 x 128 element X-Y addressable LED array fabricated from green-emitting gallium phosphide. The LED array is interfaced with a 128 x 128 matrix TV camera. Associated electronics provides for seven levels of grey scale above zero with a grey scale ratio of square root of 2. Picture elements are on 0.008 inch centers resulting in a resolution of 125 lines-per-inch and a display area of approximately 1 sq. in. The LED array concept lends itself to modular construction, permitting assembly of a flat panel screen of any desired size from 1 x 1 inch building blocks without loss of resolution. A wide range of prospective aerospace applications exist extending from helmet-mounted systems involving small dedicated arrays to multimode cockpit displays constructed as modular screens. High-resolution LED arrays are already used as CRT replacements in military film-marking reconnaissance applications.

Conformal displays: human factor analysis of innovative landing aids

Science.gov (United States)

Schmerwitz, Sven; Lueken, Thomas; Doehler, Hans-Ullrich; Peinecke, Niklas; Ernst, Johannes M.; da Silva Rosa, David L.

2017-05-01

In the past couple of years, research on display content for helicopter operations headed in a new direction. The already reached goals could evolve into a paradigm change for information visualization. Technology advancements allow implementing three-dimensional and conformal content on a helmet-mounted see-through device. This superimposed imagery inherits the same optical flow as the environment. It is supposed to ease switching between display information and environmental cues. The concept is neither pathbreaking nor new, but it has not been successfully established in aviation yet. Nevertheless, there are certainly some advantages to expect-at least from perspective of a human-centered system design. Within the following pages, the next generation displays will be presented and discussed with a focus on human factors. Beginning with recalling some human factor related research facts, an experiment comparing the former two-dimensional research displays will be presented. Before introducing the DLR conformal symbol set and the three experiments about an innovative drift, indication related research activities toward conformal symbol sets will be addressed.

A Depth-Based Head-Mounted Visual Display to Aid Navigation in Partially Sighted Individuals

Science.gov (United States)

Hicks, Stephen L.; Wilson, Iain; Muhammed, Louwai; Worsfold, John; Downes, Susan M.; Kennard, Christopher

2013-01-01

Independent navigation for blind individuals can be extremely difficult due to the inability to recognise and avoid obstacles. Assistive techniques such as white canes, guide dogs, and sensory substitution provide a degree of situational awareness by relying on touch or hearing but as yet there are no techniques that attempt to make use of any residual vision that the individual is likely to retain. Residual vision can restricted to the awareness of the orientation of a light source, and hence any information presented on a wearable display would have to limited and unambiguous. For improved situational awareness, i.e. for the detection of obstacles, displaying the size and position of nearby objects, rather than including finer surface details may be sufficient. To test whether a depth-based display could be used to navigate a small obstacle course, we built a real-time head-mounted display with a depth camera and software to detect the distance to nearby objects. Distance was represented as brightness on a low-resolution display positioned close to the eyes without the benefit focussing optics. A set of sighted participants were monitored as they learned to use this display to navigate the course. All were able to do so, and time and velocity rapidly improved with practise with no increase in the number of collisions. In a second experiment a cohort of severely sight-impaired individuals of varying aetiologies performed a search task using a similar low-resolution head-mounted display. The majority of participants were able to use the display to respond to objects in their central and peripheral fields at a similar rate to sighted controls. We conclude that the skill to use a depth-based display for obstacle avoidance can be rapidly acquired and the simplified nature of the display may appropriate for the development of an aid for sight-impaired individuals. PMID:23844067

Google Glass Glare: disability glare produced by a head-mounted visual display.

Science.gov (United States)

Longley, Chris; Whitaker, David

2016-03-01

Head mounted displays are a type of wearable technology - a market that is projected to expand rapidly over the coming years. Probably the most well known example is the device Google Glass (or 'Glass'). Here we investigate the extent to which the device display can interfere with normal visual function by producing monocular disability glare. Contrast sensitivity was measured in two normally sighted participants, 32 and 52 years of age. Data were recorded for the right eye, the left eye and then again in a binocular condition. Measurements were taken both with and without the Glass in place, across a range of stimulus luminance levels using a two-alternative forced-choice methodology. The device produced a significant reduction in contrast sensitivity in the right eye (>0.5 log units). The level of disability glare increased as stimulus luminance was reduced in a manner consistent with intraocular light scatter, resulting in a veiling retinal illuminance. Sensitivity in the left eye was unaffected. A significant reduction in binocular contrast sensitivity occurred at lower luminance levels due to a loss of binocular summation, although binocular sensitivity was not found to fall below the sensitivity of the better monocular level (binocular inhibition). Head mounted displays such as Google Glass have the potential to cause significant disability glare in the eye exposed to the visual display, particularly under conditions of low luminance. They can also cause a more modest binocular reduction in sensitivity by eliminating the benefits of binocular summation. © 2015 The Authors Ophthalmic & Physiological Optics © 2015 The College of Optometrists.

Immersive virtual walk-through development for tokamak using active head mounted display

International Nuclear Information System (INIS)

Dutta, Pramit

2015-01-01

A fully immersive virtual walk-through of the SST-1 tokamak has been developed. The virtual walkthrough renders the virtual model of SST-1 tokamak through a active stereoscopic head mounted display to visualize the virtual environment. All locations inside and outside of the reactor can be accessed and reviewed. Such a virtual walkthrough provides a 1:1 scale visualization of all components of the tokamak. To achieve such a virtual model, the graphical details of the tokamak CAD model are enhanced. Such enhancements are provided to improve lighting conditions at various locations, texturing of components to have a realistic visual effect and 360° rendering for ease of access. The graphical enhancements also include the redefinition of the facets to optimize the surface triangles to remove lags in display during visual rendering. Two separate algorithms are developed to interact with the virtual model. A fly-by algorithm, developed using C#, uses inputs from a commercial joystick to navigate within the virtual environment. The second algorithm uses the IR and gyroscopic tracking system of the head mounted display to render view as per the current pose of the user within the virtual environment and the direction of view. Such a virtual walk-thorough can be used extensively for design review and integration, review of new components, operator training for remote handling, operations, upgrades of tokamak, etc. (author)

Use of Highways in the Sky and a virtual pad for landing Head Up Display symbology to enable improved helicopter pilots situation awareness and workload in degraded visual conditions.

Science.gov (United States)

Stanton, Neville A; Plant, Katherine L; Roberts, Aaron P; Allison, Craig K

2017-12-15

Flight within degraded visual conditions is a great challenge to pilots of rotary-wing craft. Environmental cues typically used to guide interpretation of speed, location and approach can become obscured, forcing the pilots to rely on data available from in-cockpit instrumentation. To ease the task of flight during degraded visual conditions, pilots require easy access to flight critical information. The current study examined the effect of 'Highways in the Sky' symbology and a conformal virtual pad for landing presented using a Head Up Display (HUD) on pilots' workload and situation awareness for both clear and degraded conditions across a series of simulated rotary-wing approach and landings. Results suggest that access to the HUD lead to significant improvements to pilots' situation awareness, especially within degraded visual conditions. Importantly, access to the HUD facilitated pilot awareness in all conditions. Results are discussed in terms of future HUD development. Practitioner Summary: This paper explores the use of a novel Heads Up Display, to facilitate rotary-wing pilots' situation awareness and workload for simulated flights in both clear and degraded visual conditions. Results suggest that access to HUD facilitated pilots' situation awareness, especially when flying in degraded conditions.

Integration Head Mounted Display Device and Hand Motion Gesture Device for Virtual Reality Laboratory

Science.gov (United States)

Rengganis, Y. A.; Safrodin, M.; Sukaridhoto, S.

2018-01-01

Virtual Reality Laboratory (VR Lab) is an innovation for conventional learning media which show us whole learning process in laboratory. There are many tools and materials are needed by user for doing practical in it, so user could feel new learning atmosphere by using this innovation. Nowadays, technologies more sophisticated than before. So it would carry in education and it will be more effective, efficient. The Supported technologies are needed us for making VR Lab such as head mounted display device and hand motion gesture device. The integration among them will be used us for making this research. Head mounted display device for viewing 3D environment of virtual reality laboratory. Hand motion gesture device for catching user real hand and it will be visualized in virtual reality laboratory. Virtual Reality will show us, if using the newest technologies in learning process it could make more interesting and easy to understand.

Head-mounted display for use in functional endoscopic sinus surgery

Science.gov (United States)

Wong, Brian J.; Lee, Jon P.; Dugan, F. Markoe; MacArthur, Carol J.

1995-05-01

Since the introduction of functional endoscopic sinus surgery (FESS), the procedure has undergone rapid change with evolution keeping pace with technological advances. The advent of low cost charge coupled device 9CCD) cameras revolutionized the practice and instruction of FESS. Video-based FESS has allowed for documentation of the surgical procedure as well as interactive instruction during surgery. Presently, the technical requirements of video-based FESS include the addition of one or more television monitors positioned strategically in the operating room. Thought video monitors have greatly enhanced surgical endoscopy by re- involving nurses and assistants in the actual mechanics of surgery, video monitors require the operating surgeon to be focused on the screen instead of the patient. In this study, we describe the use of a new low-cost liquid crystal display (LCD) based device that functions as a monitor but is mounted on the head on a visor (PT-O1, O1 Products, Westlake Village, CA). This study illustrates the application of these HMD devices to FESS operations. The same surgeon performed the operation in each patient. In one nasal fossa, surgery was performed using conventional video FESS methods. The contralateral side was operated on while wearing the head mounted video display. The device had adequate resolution for the purposes of FESS. No adverse effects were noted intraoperatively. The results on the patients ipsalateral and contralateral sides were similar. The visor did eliminated significant torsion of the surgeon's neck during the operation, while at the same time permitted simultaneous viewing of both the patient and the intranasal surgical field.

Observation of motorcycle helmet use rates in Michigan after partial repeal of the universal motorcycle helmet law.

Science.gov (United States)

Buckley, Lisa; Bingham, C Raymond; Flannagan, Carol A; Carter, Patrick M; Almani, Farideh; Cicchino, Jessica B

2016-10-01

Motorcycle crashes result in a significant health burden, including many fatal injuries and serious non-fatal head injuries. Helmets are highly effective in preventing such trauma, and jurisdictions that require helmet use of all motorcyclists have higher rates of helmet use and lower rates of head injuries among motorcyclists. The current study examines helmet use and characteristics of helmeted operators and their riding conditions in Michigan, following a weakening of the state's universal motorcycle helmet use law in April 2012. Data on police-reported crashes occurring during 2012-14 and from a stratified roadside observational survey undertaken in Southeast Michigan during May-September 2014 were used to estimate statewide helmet use rates. Observed helmet use was more common among operators of sports motorcycles, on freeways, and in the morning, and least common among operators of cruisers, on minor arterials, and in the afternoon. The rate of helmet use across the state was estimated at 75%, adjusted for roadway type, motorcycle class, and time of day. Similarly, the helmet use rate found from examination of crash records was 73%. In the observation survey, 47% of operators wore jackets, 94% wore long pants, 54% wore boots, and 80% wore gloves. Protective clothing of jackets and gloves was most often worn by sport motorcycle operators and long pants and boots most often by riders of touring motorcycles. Findings highlight the much lower rate of helmet use in Michigan compared with states that have a universal helmet use law, although the rate is higher than observed in many states with partial helmet laws. Targeted interventions aimed at specific groups of motorcyclists and situations where helmet use rates are particularly low should be considered to increase helmet use. Copyright © 2016 Elsevier Ltd. All rights reserved.

Report of the Panel on Tactical Aircraft

Science.gov (United States)

1968-07-01

Study the design, cost, and operational utility of a helmet-mounted sight coupled with a laser ranger to provide range and bearing information on...DEVELOPMENT PROGRAM for coordinated use of optical aids SENSORS INTERFACES DISPLAYS EYEGLASS EYEBALL WALLEYE LLLTV IMAGE INTENSIFIER FLIR ATAR...operational utility of a helmet-mounted sight coupled with a laser ranger to provide range and bearing infor- mation on targets sighted by visual

Hybrid diffractive-refractive optical system design of head-mounted display for augmented reality

Science.gov (United States)

Zhang, Huijuan

2005-02-01

An optical see-through head-mounted display for augmented reality is designed in this paper. Considering the factors, such as the optical performance, the utilization ratios of energy of real world and virtual world, the feelings of users when he wears it and etc., a structure of the optical see-through is adopted. With the characteristics of the particular negative dispersive and the power of realizing random-phase modulation, the diffractive surface is helpful for optical system of reducing weight, simplifying structure and etc., and a diffractive surface is introduced in our optical system. The optical system with 25 mm eye relief, 12 mm exit pupil and 20° (H)x15.4° (V) field-of-view is designed. The utilization ratios of energy of real world and virtual world are 1/4 and 1/2, respectively. The angular resolution of display is 0.27 mrad and it less than that of the minimum of human eyes. The diameter of this system is less than 46mm, and it applies the binocular. This diffractive-refractive optical system of see-through head-mounted display not only satisfies the demands of user"s factors in structure, but also with high resolution, very small chromatic aberration and distortion, and satisfies the need of augmented reality. In the end, the parameters of the diffractive surface are discussed.

An Analysis of Eye Movements with Helmet Mounted Displays

Science.gov (United States)

2014-03-27

correct the condition with the attendant risks of loss of the involved ovary, bleeding, infection, or death. d. Menstrual Flow - Prolonged exposures to...vibration could theoretically result in menstrual flow alterations. To date, female subjects at this facility have not reported any unusual problems...ICD Distribution: Original filed with protocol records by PI; copy 1, subjec Appendix C: Testing Checklist 74 An Investigation

Optical Head-Mounted Computer Display for Education, Research, and Documentation in Hand Surgery.

Science.gov (United States)

Funk, Shawn; Lee, Donald H

2016-01-01

Intraoperative photography and capturing videos is important for the hand surgeon. Recently, optical head-mounted computer display has been introduced as a means of capturing photographs and videos. In this article, we discuss this new technology and review its potential use in hand surgery. Copyright © 2016 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Visual search asymmetries within color-coded and intensity-coded displays.

Science.gov (United States)

Yamani, Yusuke; McCarley, Jason S

2010-06-01

Color and intensity coding provide perceptual cues to segregate categories of objects within a visual display, allowing operators to search more efficiently for needed information. Even within a perceptually distinct subset of display elements, however, it may often be useful to prioritize items representing urgent or task-critical information. The design of symbology to produce search asymmetries (Treisman & Souther, 1985) offers a potential technique for doing this, but it is not obvious from existing models of search that an asymmetry observed in the absence of extraneous visual stimuli will persist within a complex color- or intensity-coded display. To address this issue, in the current study we measured the strength of a visual search asymmetry within displays containing color- or intensity-coded extraneous items. The asymmetry persisted strongly in the presence of extraneous items that were drawn in a different color (Experiment 1) or a lower contrast (Experiment 2) than the search-relevant items, with the targets favored by the search asymmetry producing highly efficient search. The asymmetry was attenuated but not eliminated when extraneous items were drawn in a higher contrast than search-relevant items (Experiment 3). Results imply that the coding of symbology to exploit visual search asymmetries can facilitate visual search for high-priority items even within color- or intensity-coded displays. PsycINFO Database Record (c) 2010 APA, all rights reserved.

A Survey of Calibration Methods for Optical See-Through Head-Mounted Displays

OpenAIRE

Grubert, Jens; Itoh, Yuta; Moser, Kenneth; Swan II, J. Edward

2017-01-01

Optical see-through head-mounted displays (OST HMDs) are a major output medium for Augmented Reality, which have seen significant growth in popularity and usage among the general public due to the growing release of consumer-oriented models, such as the Microsoft Hololens. Unlike Virtual Reality headsets, OST HMDs inherently support the addition of computer-generated graphics directly into the light path between a user's eyes and their view of the physical world. As with most Augmented and Vi...

Build Your Own Equiluminance Helmet

OpenAIRE

Connolly, Salammbo; Connolly, Denis; Cleary, Anne; Herman, Laura; Cavanagh, Patrick

2017-01-01

A wearable ?helmet? version of the S cone isolating technique was constructed to explore vision at equiluminance. For my high school summer science project, I visited parks and streets while wearing the helmet and report that the helmet appears to have captured the main properties described for the large-scale, more cumbersome stage version.

Motorcycle helmet use laws

Science.gov (United States)

2006-01-01

The National Highway Traffic Safety Administration (NHTSA) encourages States to enact legislation that requires all motorcycle riders to wear helmets. Motorcycle helmets provide the best protection from head injury for motorcyclists involved in traff...

Passive method of eliminating accommodation/convergence disparity in stereoscopic head-mounted displays

Science.gov (United States)

Eichenlaub, Jesse B.

2005-03-01

The difference in accommodation and convergence distance experienced when viewing stereoscopic displays has long been recognized as a source of visual discomfort. It is especially problematic in head mounted virtual reality and enhanced reality displays, where images must often be displayed across a large depth range or superimposed on real objects. DTI has demonstrated a novel method of creating stereoscopic images in which the focus and fixation distances are closely matched for all parts of the scene from close distances to infinity. The method is passive in the sense that it does not rely on eye tracking, moving parts, variable focus optics, vibrating optics, or feedback loops. The method uses a rapidly changing illumination pattern in combination with a high speed microdisplay to create cones of light that converge at different distances to form the voxels of a high resolution space filling image. A bench model display was built and a series of visual tests were performed in order to demonstrate the concept and investigate both its capabilities and limitations. Results proved conclusively that real optical images were being formed and that observers had to change their focus to read text or see objects at different distances

Investigating effective support mounts for fans during display by exploring new technologies

Directory of Open Access Journals (Sweden)

Sarah Bright

2012-06-01

Full Text Available Blaise Castle House Museum in Bristol (UK houses a large and impressive collection of 130 European fans ranging from 1700-1950 with 60 brisé and 70 other fans in a generally good condition.  This research project explored how to best support this sort of collection by using 3D fabrication technology to create bespoke mounts.  At present making mounts for fans is complex and time consuming due to the layering and structure of fans, and the need for accuracy if the mount is to support the fan sufficiently.  This project explored how creating a digital 3D image of a fan could enable 3D fabrication technologies to be used to produce an exact ‘imprint’ of the object ensuring that all areas were supported, allowing a more suitable fan display to be created.  This paper outlines the process of exploring the principles of creating mounts for fans; narrates the process of selecting suitable objects for display, and the process of creating a digitally-produced fan mount.Blaise Castle House Museum à Bristol (Royaume-Uni abrite une importante et impressionnante collection de 130 éventails européens, datés de 1700 à 1950, dont 60 brisés et 70 autres dans un bon état général. Ce projet de recherche consiste à présenter au mieux ce type de collection en utilisant la technologie de fabrication 3D pour créer des supports sur mesure. À l'heure actuelle la conception de présentoirs est complexe et prend du temps, en raison de la structure des objets, et d’un besoin extrême de précision lorsque l’objectif est d’apporter un soutien aux différentes composantes des éventails. Ce projet explore donc comment la création d'une image numérique 3D d'un éventail pourrait permettre à des technologies de fabrication en 3D d’être utilisées pour produire une exacte «empreinte» de l'objet et veiller à ce que toutes les composantes soient supportées, permettant ainsi de créer le présentoir. Ce document décrit le processus d

Optical see-through head-mounted display with occlusion capability

Science.gov (United States)

Gao, Chunyu; Lin, Yuxiang; Hua, Hong

2013-05-01

Lack of mutual occlusion capability between computer-rendered and real objects is one of fundamental problems for most existing optical see-through head-mounted displays (OST-HMD). Without the proper occlusion management, the virtual view through an OST-HMD appears "ghost-like", floating in the real world. To address this challenge, we have developed an innovative optical scheme that uniquely combines the eyepiece and see-through relay optics to achieve an occlusion-capable OST-HMD system with a very compelling form factor and high optical performances. The proposed display system was based on emerging freeform optical design technologies and was designed for highly efficient liquid crystal on silicon (LCoS) type spatial light modulator (SLM) and bright Organic LED (OLED) microdisplay. The proposed display technology was capable of working in both indoor and outdoor environments. Our current design offered a 1280x1024 color resolution based on 0.8" microdisplay and SLM. The MTF values for the majority of the fields at the cutoff frequency of 40lps/mm, which is determined by the pixel size of the microdisplay, are better than 15%. The design achieved a diagonal FOV of 40 degrees, 31.7 degrees horizontally and 25.6 degrees vertically, an exit pupil diameter of 8mm (non-vignetted), and an eye clearance of 18mm. The optics weights about 20 grams per eye. Our proposed occlusion capable OST-HMD system can easily find myriads of applications in various military and commercial sectors such as military training, gaming and entertainment.

Impact of Soldier Helmet Configuration on Survivability

Science.gov (United States)

2011-03-01

helmet cannot sit too low, which is evident when the helmet covers the eyebrows and the helmet interferes with eyewear . The helmet should remain in...agencies, academia, and private industry have also aided in model development. ORCA is a high-resolution computerized personnel casualty model that can

Mirror position display equipment for the target chamber mirror mounts of the LASL HELIOS laser fusion facility

International Nuclear Information System (INIS)

Wells, F.D.; Remington, D.A.

1979-01-01

Equipment has been fabricated which records the absolute positions of sixteen mirror mounts used to direct and focus eight high-energy laser beams for research in laser induced fusion. Each mirror mount is driven by three stepping motors, controlled to produce the motions of Focus, Tilt, and Rotate relative to the target. Stepping of the motors is sensed by incremental optical encoders coupled to the motor drive shafts. Outputs from the encoder tracks are multiplexed to a microprocessor which transmits motor step information via a fiber optical data link to a Mirror Position Display chassis. This unit accumulates the steps, stores the motor positions, displays mirror position data to the operator, and provides the equipment control functions. Standby battery power is included to retain the motor step data in the event of power failure

Federally mandating motorcycle helmets in the United States.

Science.gov (United States)

Eltorai, Adam E M; Simon, Chad; Choi, Ariel; Hsia, Katie; Born, Christopher T; Daniels, Alan H

2016-03-09

Motorcycle helmets reduce both motorcycle-related fatalities and head injuries. Motorcycle crashes are a major public health concern which place economic stress on the U.S. healthcare system. Although statewide universal motorcycle helmet laws effectively increase helmet use, most state helmet laws do not require every motorcycle rider to wear a helmet. Herein, we propose and outline the solution of implementing federal motorcycle helmet law, while addressing potential counterarguments. The decision to ride a motorcycle without a helmet has consequences that affect more than just the motorcyclist. In an effort to prevent unnecessary healthcare costs, injuries, and deaths, public health efforts to increase helmet use through education and legislation should be strongly considered. Helmet use on motorcycles fits squarely within the purview of the federal government public health and economic considerations.

Registration of an on-axis see-through head-mounted display and camera system

Science.gov (United States)

Luo, Gang; Rensing, Noa M.; Weststrate, Evan; Peli, Eli

2005-02-01

An optical see-through head-mounted display (HMD) system integrating a miniature camera that is aligned with the user's pupil is developed and tested. Such an HMD system has a potential value in many augmented reality applications, in which registration of the virtual display to the real scene is one of the critical aspects. The camera alignment to the user's pupil results in a simple yet accurate calibration and a low registration error across a wide range of depth. In reality, a small camera-eye misalignment may still occur in such a system due to the inevitable variations of HMD wearing position with respect to the eye. The effects of such errors are measured. Calculation further shows that the registration error as a function of viewing distance behaves nearly the same for different virtual image distances, except for a shift. The impact of prismatic effect of the display lens on registration is also discussed.

The implementation of a municipal indoor ice skating helmet policy: effects on helmet use, participation and attitudes.

Science.gov (United States)

O'Mahony-Menton, Colleen; Willmore, Jacqueline; Russell, Katherine

2015-12-01

In Ottawa, between 2005 and 2009 there was an annual average of 47.2 head injuries due to ice skating in children and youth (1-19 years of age) requiring a visit to the emergency department, with the highest rates among those aged 5-14 years. Between 2002 and 2007, only 6% of children were wearing a helmet during ice skating when the head injury occurred. During indoor public skating sessions, 93% of children (skating helmet policy coupled with education and promotional activities on helmet use, participation and attitudes towards helmet use. An ice skating helmet policy for children (skating experience at indoor rinks during public skating sessions was developed, implemented and evaluated. Supportive activities such as discount coupons, promotional materials, a media launch, social marketing and staff training are described. The helmet policy was associated with increased helmet use for young children and for older children, youth and adults not included in the policy, without decreasing attendance to public skating sessions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Effects of repealing the motorcycle helmet law in Michigan.

Science.gov (United States)

Hothem, Zachary; Simon, Robert; Barnes, Wesley; Mohammad, Azmath; Sevak, Shruti; Ziegler, Kathryn; Iacco, Anthony; Janczyk, Randy

2017-09-01

In 2012, Michigan repealed its universal helmet law. Our study assessed the clinical impact of this repeal. Our trauma database was queried retrospectively for 2 motorcycle riding seasons before and 3 seasons after repeal. On-scene death data was obtained from the Medical Examiner. Helmet use in hospitalized patients decreased after the helmet law repeal. Non-helmeted patients had a significant increased rate of head injury. Non-helmeted patients were more likely to die during hospitalization. While, helmet use and drugs/alcohol status significantly affected the risk for head injury, only drug/alcohol had a significant effect on overall mortality. Following helmet law repeal, helmet use has decreased. Helmet status and drug/alcohol use was found to significantly increase risk of head injury. Although overall mortality was only affected by drug/alcohol use, non-helmeted patients did have a higher inpatient mortality. These findings deserve furthermore study and may provide a basis for reinstating the universal helmet law. Copyright © 2016 Elsevier Inc. All rights reserved.

SAFETY ALERT: Electrical insulation defect on safety helmets

CERN Multimedia

HSE Unit

2013-01-01

Contrarily to the information provided until 31 May 2013, some “Euro Protection” safety helmets do not respect any of the requirements for electrical insulation.   This alert concerns the safety helmets identified under the following SCEM numbers: 50.43.30.050.4 white 50.43.30.060.2 yellow 50.43.30.070.0 blue This amounts up to several hundreds of helmets on the CERN site. People who need to wear an electrically insulated safety helmet for their activities, must from now on acquire a duly insulated item to be found on the CERN store under the following SCEM numbers: 50.43.30.210.6: Petzl Vertex ST Helmet (without vent) 50.43.30.300.1: IDRA Helmet with a visor for electrical work As for the people who do not need to wear an electrically insulated helmet for their activities, they can continue working with the aforementioned helmets. For your information, please take note of the maximum use limit of each helmet: “Euro Protection” Safety Helme...

The Influence of Various Factors on High School Football Helmet Face Mask Removal: A Retrospective, Cross-Sectional Analysis

Science.gov (United States)

Swartz, Erik E; Decoster, Laura C; Norkus, Susan A; Cappaert, Thomas A

2007-01-01

Context: Most research on face mask removal has been performed on unused equipment. Objective: To identify and compare factors that influence the condition of helmet components and their relationship to face mask removal. Design: A cross-sectional, retrospective study. Setting: Five athletic equipment reconditioning/recertification facilities. Participants: 2584 helmets from 46 high school football teams representing 5 geographic regions. Intervention(s): Helmet characteristics (brand, model, hardware components) were recorded. Helmets were mounted and face mask removal was attempted using a cordless screwdriver. The 2004 season profiles and weather histories were obtained for each high school. Main Outcome Measure(s): Success and failure (including reason) for removal of 4 screws from the face mask were noted. Failure rates among regions, teams, reconditioning year, and screw color (type) were compared. Weather histories were compared. We conducted a discriminant analysis to determine if weather variables, region, helmet brand and model, reconditioning year, and screw color could predict successful face mask removal. Metallurgic analysis of screw samples was performed. Results: All screws were successfully removed from 2165 (84%) helmets. At least 1 screw could not be removed from 419 (16%) helmets. Significant differences were found for mean screw failure per helmet among the 5 regions, with the Midwest having the lowest failure rate (0.08 ± 0.38) and the Southern (0.33 ± 0.72), the highest. Differences were found in screw failure rates among the 46 teams (F1,45 = 9.4, P < .01). Helmets with the longest interval since last reconditioning (3 years) had the highest failure rate, 0.47 ± 0.93. Differences in success rates were found among 4 screw types (χ21,4 = 647, P < .01), with silver screws having the lowest percentage of failures (3.4%). A discriminant analysis (Λ = .932, χ214,n=2584 = 175.34, P < .001) revealed screw type to be the strongest predictor of

A Dose of Reality: Overcoming Usability Challenges\\ud in VR Head-Mounted Displays

OpenAIRE

McGill, M.; Boland, Daniel; Murray-Smith, Roderick; Brewster, Stephen

2015-01-01

We identify usability challenges facing consumers adopting\\ud Virtual Reality (VR) head-mounted displays (HMDs) in a survey\\ud of 108 VR HMD users. Users reported significant issues\\ud in interacting with, and being aware of their real-world\\ud context when using a HMD. Building upon existing work on\\ud blending real and virtual environments, we performed three\\ud design studies to address these usability concerns. In a typing\\ud study, we show that augmenting VR with a view of reality\\ud sig...

Virtual reality exposure treatment of agoraphobia: a comparison of computer automatic virtual environment and head-mounted display

NARCIS (Netherlands)

Meyerbröker, K.; Morina, N.; Kerkhof, G.; Emmelkamp, P.M.G.; Wiederhold, B.K.; Bouchard, S.; Riva, G.

2011-01-01

In this study the effects of virtual reality exposure therapy (VRET) were investigated in patients with panic disorder and agoraphobia. The level of presence in VRET was compared between using either a head-mounted display (HMD) or a computer automatic virtual environment (CAVE). Results indicate

Helmet Use and Head Injury in Homer's Iliad.

Science.gov (United States)

Swinney, Christian

2016-06-01

Homer's detailed descriptions of head injuries inflicted during the Trojan War are of particular interest to individuals in the medical community. Although studies have examined the prevalence of such injuries, none have examined the preventive measures taken to avoid them. An in-depth review of helmet use in Homer's Iliad was conducted to address this previously unexplored facet of the epic. An English translation of Homer's text was reviewed for all references to helmet use. The number of helmet references in each book was recorded, along with other pertinent details for each reference. There were 87 references to helmets (40 combat, 47 noncombat). The helmet belonged to a Greek warrior in 41 cases (47.1%), a Trojan warrior in 38 cases (43.6%), a divinity in 5 cases (5.7%), and a general group of warriors in 3 cases (3.4%). Helmet use provided protective benefit to Greek warriors at a rate of 30.0% (3 of 10) and Trojan warriors at a rate of 11.1% (2 of 18). This difference was not statistically significant (P = 0.23). The overall combined protective benefit of helmet use in the text was 17.9% (5 of 28). Helmets belonging to 15 specific Greek warriors and 18 specific Trojan warriors were referenced in the text. Helmets belonging to Hector (n = 12) and Achilles (n = 8) were most frequently mentioned. Helmet use and head injury both play a prominent role in Homer's Iliad. Helmets are frequently used in combat settings but with relatively little success. Helmets are also used in various noncombat settings. Copyright © 2016 Elsevier Inc. All rights reserved.

Markerless Augmented Reality via Stereo Video See-Through Head-Mounted Display Device

Directory of Open Access Journals (Sweden)

Chung-Hung Hsieh

2015-01-01

Full Text Available Conventionally, the camera localization for augmented reality (AR relies on detecting a known pattern within the captured images. In this study, a markerless AR scheme has been designed based on a Stereo Video See-Through Head-Mounted Display (HMD device. The proposed markerless AR scheme can be utilized for medical applications such as training, telementoring, or preoperative explanation. Firstly, a virtual model for AR visualization is aligned to the target in physical space by an improved Iterative Closest Point (ICP based surface registration algorithm, with the target surface structure reconstructed by a stereo camera pair; then, a markerless AR camera localization method is designed based on the Kanade-Lucas-Tomasi (KLT feature tracking algorithm and the Random Sample Consensus (RANSAC correction algorithm. Our AR camera localization method is shown to be better than the traditional marker-based and sensor-based AR environment. The demonstration system was evaluated with a plastic dummy head and the display result is satisfactory for a multiple-view observation.

Amblyopia treatment of adults with dichoptic training using the virtual reality oculus rift head mounted display: preliminary results.

Science.gov (United States)

Žiak, Peter; Holm, Anders; Halička, Juraj; Mojžiš, Peter; Piñero, David P

2017-06-28

The gold standard treatments in amblyopia are penalizing therapies, such as patching or blurring vision with atropine that are aimed at forcing the use of the amblyopic eye. However, in the last years, new therapies are being developed and validated, such as dichoptic visual training, aimed at stimulating the amblyopic eye and eliminating the interocular supression. To evaluate the effect of dichoptic visual training using a virtual reality head mounted display in a sample of anisometropic amblyopic adults and to evaluate the potential usefulness of this option of treatment. A total of 17 subjects (10 men, 7 women) with a mean age of 31.2 years (range, 17-69 year) and anisometropic amblyopia were enrolled. Best corrected visual acuity (BCVA) and stereoacuity (Stereo Randot graded circle test) changes were evaluated after 8 sessions (40 min per session) of dichoptic training with the computer game Diplopia Game (Vivid Vision) run in the Oculus Rift OC DK2 virtual reality head mounted display (Oculus VR). Mean BCVA in amblyopic eye improved significantly from a logMAR value of 0.58 ± 0.35 before training to a post-training value of 0.43 ± 0.38 (p virtual reality head mounted display seems to be an effective option of treatment in adults with anisometropic amblyopia. Future clinical trials are needed to confirm this preliminary evidence. Trial ID: ISRCTN62086471 . Date registered: 13/06/2017. Retrospectively registered.

Motorcycle helmets: What about their coating?

Science.gov (United States)

Schnegg, Michaël; Massonnet, Geneviève; Gueissaz, Line

2015-07-01

In traffic accidents involving motorcycles, paint traces can be transferred from the rider's helmet or smeared onto its surface. These traces are usually in the form of chips or smears and are frequently collected for comparison purposes. This research investigates the physical and chemical characteristics of the coatings found on motorcycles helmets. An evaluation of the similarities between helmet and automotive coating systems was also performed.Twenty-seven helmet coatings from 15 different brands and 22 models were considered. One sample per helmet was collected and observed using optical microscopy. FTIR spectroscopy was then used and seven replicate measurements per layer were carried out to study the variability of each coating system (intravariability). Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were also performed on the infrared spectra of the clearcoats and basecoats of the data set. The most common systems were composed of two or three layers, consistently involving a clearcoat and basecoat. The coating systems of helmets with composite shells systematically contained a minimum of three layers. FTIR spectroscopy results showed that acrylic urethane and alkyd urethane were the most frequent binders used for clearcoats and basecoats. A high proportion of the coatings were differentiated (more than 95%) based on microscopic examinations. The chemical and physical characteristics of the coatings allowed the differentiation of all but one pair of helmets of the same brand, model and color. Chemometrics (PCA and HCA) corroborated classification based on visual comparisons of the spectra and allowed the study of the whole data set at once (i.e., all spectra of the same layer). Thus, the intravariability of each helmet and its proximity to the others (intervariability) could be more readily assessed. It was also possible to determine the most discriminative chemical variables based on the study of the PCA loadings. Chemometrics

Children and cycle helmets -- the case against.

Science.gov (United States)

McCarthy, M

1996-03-01

Much of the literature on child cycling accidents appears to blame the child as a victim, as though children's activities of playing and travelling were somehow wrong and that children are at fault when an adult drives a car over them. This adult-centred approach then leads to the idea that children should protect themselves with helmets, and that they are to blame if they are injured. However, adults who continue to hold the fantasy that helmets might be of value should know that the British Standard for cycle helmets protects only in a vertical fall of 1 m -- certainly not motor vehicle crashes. Thicker motor cycle helmets would give better protection but, of course, are heavier (and therefore unsaleable). Yet even with compulsory wearing helmets, more motor cyclists still die of head injuries than pedal cyclists. In the Newcastle study, five times as many child pedestrians died of road accidents as child cyclists. Convinced helmeteers should recommend all children playing or travelling in the streets to wear helmets (presumably heavy motor-cycle helmets). Slightly more sceptical proponents might prefer half of them -- in a randomized controlled trial. Car driving appears to have as serious health consequences as tobacco, alcohol and drugs, and to be as addictive (McCarthy 1992). Helmets are similar to filters in cigarettes -- they give the illusion of safety to both consumer and producer of the product, but the illusion is fatal. Yet, for their cardiovascular and mental health, children should have the freedom to cycle in safety around where they live. A profound change in the habits of adults is needed, rather than suits of armour for children.

Submissive display in young helmeted guineafowl

African Journals Online (AJOL)

1984-06-04

Jun 4, 1984 ... ly identifiable birds in the Krugersdorp Game Reserve. (26°05'S/27°46'E) from April 1982 to March 1984. Submissive displays were observed mainly between a par- ent/guardian (senior flock members) and offspring. These activities are seen throughout the year, but appear to peak just after the fledging of ...

Advanced Extravehicular Helmet Assembly, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — The current NASA spacesuit community is focusing on utilizing a 13" hemispherical helmet for the next generation of extravehicular activity spacesuits. This helmet...

Correlates and Barriers Associated with Motorcycle Helmet Use in Wa, Ghana.

Science.gov (United States)

Akaateba, Millicent Awialie; Yakubu, Ibrahim; Akanbang, Bernard Afiik Akanpabadai

2015-01-01

This study was conducted to investigate the correlates and barriers to helmet use among motorcycle riders in Wa, a motorcycle-predominant town in Ghana. An additional objective was to determine the association between helmet use and riders' knowledge, attitudes, and beliefs toward helmets. Cross-sectional surveys including both observation of helmet use and interviews were conducted among motorcycle riders at 6 randomly selected fuel stations and 4 motorcycle service centers within and outside the Central Business District of Wa. Questions covered riders' sociodemographic and riding characteristics, helmet use, reasons for use or nonuse of helmets, and knowledge, attitudes, and beliefs about helmets. Analyses were based on frequencies and testing of strength of association using adjusted odds ratios (with 95% confidence intervals) in binary logistic regression. The prevalence of helmet use among the 271 sampled riders was 46% (95% confidence interval [CI], 40.2-52.0). Gender, age, marital status, and occupation were significant sociodemographic correlates of helmet use in Wa. Compared to currently married riders, unmarried riders were 5 times less likely to use a helmet. No significant association existed between riders' educational attainment and helmet use. Helmet use was also positively correlated with helmet ownership and license holding. The leading reasons stated for helmet nonuse among nonusers were not traveling a long distance and helmets block vision and hearing. Protection from injury, legal requirement, and coping with the police for fear of being accosted for helmet nonuse were identified as common reasons for helmet use. Positive attitudes and beliefs were also significantly correlated with helmet use. Despite the existence of a legislation mandating the use of helmets on all roads as well as the high level of awareness among riders on this legislation and the benefits of helmets, the incidence of helmet use among motorists continue to be low in Wa

Photosensor-Based Latency Measurement System for Head-Mounted Displays

Directory of Open Access Journals (Sweden)

Min-Woo Seo

2017-05-01

Full Text Available In this paper, a photosensor-based latency measurement system for head-mounted displays (HMDs is proposed. The motion-to-photon latency is the greatest reason for motion sickness and dizziness felt by users when wearing an HMD system. Therefore, a measurement system is required to accurately measure and analyze the latency to reduce these problems. The existing measurement system does not consider the actual physical movement in humans, and its accuracy is also very low. However, the proposed system considers the physical head movement and is highly accurate. Specifically, it consists of a head position model-based rotary platform, pixel luminance change detector, and signal analysis and calculation modules. Using these modules, the proposed system can exactly measure the latency, which is the time difference between the physical movement for a user and the luminance change of an output image. In the experiment using a commercial HMD, the latency was measured to be up to 47.05 ms. In addition, the measured latency increased up to 381.17 ms when increasing the rendering workload in the HMD.

The Effect of Head Mounted Display Weight and Locomotion Method on the Perceived Naturalness of Virtual Walking Speeds

DEFF Research Database (Denmark)

Nilsson, Niels Chr.; Serafin, Stefania; Nordahl, Rolf

This poster details a study investigating the effect of Head Mounted Display (HMD) weight and locomotion method (Walking-In-Place and treadmill walking) on the perceived naturalness of virtual walking speeds. The results revealed significant main effects of movement type, but no significant effec...

The mystery of the missing Viking helmets.

Science.gov (United States)

Wester, K

2000-11-01

Based on archaeological finds and old Norse literature, this study describes the Scandinavian helmet tradition from the Bronze Age to the Viking Age, as well as the Viking culture, with special emphasis on weaponry and head protection. Contrary to what is commonly believed, the study shows that metal helmets must have been used very infrequently by the Vikings. In fact, only one Viking helmet has been retrieved in Scandinavia. Possible reasons for the widespread misconception that the Vikings wore helmets are discussed, and the responsibility for not correcting this misunderstanding is placed with the archaeological profession.

Volumetric, dashboard-mounted augmented display

Science.gov (United States)

Kessler, David; Grabowski, Christopher

2017-11-01

The optical design of a compact volumetric display for drivers is presented. The system displays a true volume image with realistic physical depth cues, such as focal accommodation, parallax and convergence. A large eyebox is achieved with a pupil expander. The windshield is used as the augmented reality combiner. A freeform windshield corrector is placed at the dashboard.

Simulation-based assessment for construction helmets.

Science.gov (United States)

Long, James; Yang, James; Lei, Zhipeng; Liang, Daan

2015-01-01

In recent years, there has been a concerted effort for greater job safety in all industries. Personnel protective equipment (PPE) has been developed to help mitigate the risk of injury to humans that might be exposed to hazardous situations. The human head is the most vulnerable to impact as a moderate magnitude can cause serious injury or death. That is why industries have required the use of an industrial hard hat or helmet. There have only been a few articles published to date that are focused on the risk of head injury when wearing an industrial helmet. A full understanding of the effectiveness of construction helmets on reducing injury is lacking. This paper presents a simulation-based method to determine the threshold at which a human will sustain injury when wearing a construction helmet and assesses the risk of injury for wearers of construction helmets or hard hats. Advanced finite element, or FE, models were developed to study the impact on construction helmets. The FE model consists of two parts: the helmet and the human models. The human model consists of a brain, enclosed by a skull and an outer layer of skin. The level and probability of injury to the head was determined using both the head injury criterion (HIC) and tolerance limits set by Deck and Willinger. The HIC has been widely used to assess the likelihood of head injury in vehicles. The tolerance levels proposed by Deck and Willinger are more suited for finite element models but lack wide-scale validation. Different cases of impact were studied using LSTC's LS-DYNA.

Visual Suppression of Monocularly Presented Symbology Against a Fused Background in a Simulation and Training Environment

National Research Council Canada - National Science Library

Winterbottom, Marc D; Patterson, Robert; Pierce, Byron J; Taylor, Amanda

2006-01-01

.... This may create interocular differences in image characteristics that could disrupt binocular vision by provoking visual suppression, thus reducing visibility of the background scene, monocular symbology...

Application of Auxetic Foam in Sports Helmets

Directory of Open Access Journals (Sweden)

Leon Foster

2018-03-01

Full Text Available This investigation explored the viability of using open cell polyurethane auxetic foams to augment the conformable layer in a sports helmet and improve its linear impact acceleration attenuation. Foam types were compared by examining the impact severity on an instrumented anthropomorphic headform within a helmet consisting of three layers: a rigid shell, a stiff closed cell foam, and an open cell foam as a conformable layer. Auxetic and conventional foams were interchanged to act as the helmet’s conformable component. Attenuation of linear acceleration was examined by dropping the combined helmet and headform on the front and the side. The helmet with auxetic foam reduced peak linear accelerations (p < 0.05 relative to its conventional counterpart at the highest impact energy in both orientations. Gadd Severity Index reduced by 11% for frontal impacts (38.9 J and 44% for side impacts (24.3 J. The conformable layer within a helmet can influence the overall impact attenuating properties. The helmet fitted with auxetic foam can attenuate impact severity more than when fitted with conventional foam, and warrants further investigation for its potential to reduce the risk of traumatic brain injuries in sport specific impacts.

Visual Search and Target Cueing: A Comparison of Head-Mounted Versus Hand-Held Displays on the Allocation of Visual Attention

National Research Council Canada - National Science Library

Yeh, Michelle; Wickens, Christopher D

1998-01-01

We conducted a study to examine the effects of target cueing and conformality with a hand-held or head-mounted display to determine their effects on visual search tasks requiring focused and divided attention...

A low-cost multimodal head-mounted display system for neuroendoscopic surgery.

Science.gov (United States)

Xu, Xinghua; Zheng, Yi; Yao, Shujing; Sun, Guochen; Xu, Bainan; Chen, Xiaolei

2018-01-01

With rapid advances in technology, wearable devices as head-mounted display (HMD) have been adopted for various uses in medical science, ranging from simply aiding in fitness to assisting surgery. We aimed to investigate the feasibility and practicability of a low-cost multimodal HMD system in neuroendoscopic surgery. A multimodal HMD system, mainly consisted of a HMD with two built-in displays, an action camera, and a laptop computer displaying reconstructed medical images, was developed to assist neuroendoscopic surgery. With this intensively integrated system, the neurosurgeon could freely switch between endoscopic image, three-dimensional (3D) reconstructed virtual endoscopy images, and surrounding environment images. Using a leap motion controller, the neurosurgeon could adjust or rotate the 3D virtual endoscopic images at a distance to better understand the positional relation between lesions and normal tissues at will. A total of 21 consecutive patients with ventricular system diseases underwent neuroendoscopic surgery with the aid of this system. All operations were accomplished successfully, and no system-related complications occurred. The HMD was comfortable to wear and easy to operate. Screen resolution of the HMD was high enough for the neurosurgeon to operate carefully. With the system, the neurosurgeon might get a better comprehension on lesions by freely switching among images of different modalities. The system had a steep learning curve, which meant a quick increment of skill with it. Compared with commercially available surgical assistant instruments, this system was relatively low-cost. The multimodal HMD system is feasible, practical, helpful, and relatively cost efficient in neuroendoscopic surgery.

Injury outcome among helmeted and non-helmeted motorcycle ...

African Journals Online (AJOL)

users are vulnerable on the road and are at high risk of death resulting from head ..... time of injury sustained head injury reflecting its importance in prevention of head .... WHO (2006) Helmets: A Road Safety Manual for Decision-makers and ...

A study of emergency American football helmet removal techniques.

Science.gov (United States)

Swartz, Erik E; Mihalik, Jason P; Decoster, Laura C; Hernandez, Adam E

2012-09-01

The purpose was to compare head kinematics between the Eject Helmet Removal System and manual football helmet removal. This quasi-experimental study was conducted in a controlled laboratory setting. Thirty-two certified athletic trainers (sex, 19 male and 13 female; age, 33 ± 10 years; height, 175 ± 12 cm; mass, 86 ± 20 kg) removed a football helmet from a healthy model under 2 conditions: manual helmet removal and Eject system helmet removal. A 6-camera motion capture system recorded 3-dimensional head position. Our outcome measures consisted of the average angular velocity and acceleration of the head in each movement plane (sagittal, frontal, and transverse), the resultant angular velocity and acceleration, and total motion. Paired-samples t tests compared each variable across the 2 techniques. Manual helmet removal elicited greater average angular velocity in the sagittal and transverse planes and greater resultant angular velocity compared with the Eject system. No differences were observed in average angular acceleration in any single plane of movement; however, the resultant angular acceleration was greater during manual helmet removal. The Eject Helmet Removal System induced greater total head motion. Although the Eject system created more motion at the head, removing a helmet manually resulted in more sudden perturbations as identified by resultant velocity and acceleration of the head. The implications of these findings relate to the care of all cervical spine-injured patients in emergency medical settings, particularly in scenarios where helmet removal is necessary. Copyright © 2012 Elsevier Inc. All rights reserved.

77 FR 48105 - Federal Motor Vehicle Safety Standards; Motorcycle Helmets

Science.gov (United States)

2012-08-13

... [Docket No. NHTSA-2012-0112] Federal Motor Vehicle Safety Standards; Motorcycle Helmets AGENCY: National... Vehicle Safety Standard for motorcycle helmets. Specifically, the final rule amended the helmet labeling... compliance test procedures of FMVSS No. 218, Motorcycle helmets, in order to make it more difficult to...

Continued Testing of Head-Mounted Displays for Deaf Education in a Planetarium

Science.gov (United States)

Hintz, Eric G.; Jones, M.; Lawler, J.; Bench, N.; Mangrubang, F. R.

2013-06-01

For more than a year now we have been developing techniques for using Head-Mounted Displays (HMD) to help accommodate a deaf audience in a planetarium environment. Our target audience is primarily children from 8 to 13 years of age, but the methodologies can be used for a wide variety of audiences. Applications also extend beyond the planetarium environment. Three tests have been done to determine if American Sign Language (ASL) can be delivered to the HMD and the student view both the planetarium show and the ASL ‘sound track’. From those early results we are now at the point of testing for comprehension improvement on a number of astronomical subjects. We will present a number of these early results.

Ballistic Characterization Of A Typical Military Steel Helmet

Directory of Open Access Journals (Sweden)

Mohamed Ali Maher

2017-08-01

Full Text Available In this study the ballistic limit of a steel helmet against a FMJ 919 mm caliber bullet is estimated. The helmet model is the typical polish helmet wz.31.The helmet material showed high strength low alloy steel material of 0.28 carbon content and 9.125 kgm2 areal density. The tensile test according to ASTM E8 showed a tensile strength of 1236.4 MPa .The average hardness value was about HV550. First shooting experiment has been executed using a 9 mm pistol based on 350 ms muzzle velocity at 5m against the simply supported helmet complete penetrations rose in this test were in the form of cracks on the helmet surface and partial penetrations were in the form of craters on the surface whose largest diameter and depth were 43 mm and 20.2 mm consequently .The second experiment was on a rifled gun arrangement 13 bullets of 919 mm caliber were shot on the examined simply supported steel helmet at a zero obliquity angle at different velocities to determine the ballistic limit velocity V50 according to MIL-STD-662F. Three major outcomes were revealed 1 the value V50 which found to be about 390 ms is higher than the one found in literature 360 ms German steel helmet model 1A1. 2 The smallest the standard deviation of the mixed results zone data the most accurate the ballistic limit is. 3Similar to the performance of blunt-ended projectiles impacting overmatching targets tD near 11 or larger It was found that the dominating failure mode of the steel helmet stuck by a hemispherical-nose projectile was plugging mode despite of having tD ratio of about 19 undermatching.

Experimental evaluation of a perspective tunnel display for three-dimensional helicopter approaches

Science.gov (United States)

Grunwald, A. J.; Robertson, J. B.; Hatfield, J. J.

1981-01-01

A computer-generated perspective tunnel display for a steep and strongly curved three-dimensional helicopter approach is studied. The necessary control variables for following a curved trajectory are analyzed, the effectiveness of superimposed predictor symbology is investigated, and a suitable predictor law is formulated. The theoretical considerations are validated by an extensive fixed-base simulator program. The tunnel display with a superimposed predictor symbol is shown to outperform conventional-type displays in its abilities to follow a curved trajectory in the presence of gust disturbances, to enter the trajectory from an unknown position outside this trajectory, as well as to monitor automatic approaches. The feasibility of the tunnel display for operation in actual flight has been demonstrated in an exploratory flight test.

Preliminary Design of an Image Quality Tester For Helmet-Mounted Displays

National Research Council Canada - National Science Library

Hsieh, Sheng-Jen

1999-01-01

...) camera and lens were selected. Hardware characteristics such as viewing angles in horizontal and vertical positions, dynamic working range at day and night, pixel resolution, focal length, and aperture ratio were evaluated...

Head and Helmet Biodynamics and Tracking Performance in Vibration Environments

National Research Council Canada - National Science Library

Smith, Suzanne D; Smith, Jeanne A

2006-01-01

...) and Up (40" elevation, 0" azimuth)], and three helmet CCs were tested. The overall head, helmet, and helmet slippage displacement rotations, and rms tracking error and percent time-on-target were evaluated...

Helmet Sensor - Transfer Function and Model Development

Science.gov (United States)

2010-09-01

that helmets be examined forensically when estimating the impact direction and location and the electronic HMSS data not be used in that determination... forensic analysis of the helmet itself is therefore recommended to determine the direction and severity of the ballistic impact 5. The helmet shell does...ot83 HTI l ot 8J HT1 lot S ,HTt IOt S , HTI l otiH HTt lotSS HTt l vt85 HTI l o)t 85 HT1 Front Level Acceleration ~~,--~----~--,30’p~g

Associations between drug use and motorcycle helmet use in fatal crashes.

Science.gov (United States)

Rossheim, Matthew E; Wilson, Fernando; Suzuki, Sumihiro; Rodriguez, Mayra; Walters, Scott; Thombs, Dennis L

2014-01-01

Helmet use reduces mortality risk for motorcyclists, regardless of drug and alcohol use. However, the association between drug use and motorcycle helmet utilization is not well known. This study examines the relationship between drug use and motorcycle helmet use among fatally injured motorcycle riders. Using data from the 2005-2009 Fatality Analysis Reporting System (FARS), we examined the association between drug use and motorcycle helmet use in a multivariable logistic regression analysis of 9861 fatally injured motorcycle riders in the United States. For fatally injured motorcycle riders, use of alcohol, marijuana, or other drugs was associated with increased odds of not wearing a motorcycle helmet, controlling for the effects of state motorcycle helmet laws and other confounding variables. Predicted probabilities indicate that helmet use substantially decreases among fatally injured riders mixing alcohol with marijuana and other drugs. Furthermore, the likelihood of helmet use between marijuana-only users and other drug users is virtually the same across all blood alcohol content (BAC) levels. This study provides evidence that alcohol, marijuana, and other drug use is associated with not wearing a motorcycle helmet in fatal motorcycle crashes. There is a clear need for additional prevention and intervention efforts that seek to change helmet and drug use norms among motorcycle riders.

Helmet wearing in Kenya: prevalence, knowledge, attitude, practice and implications.

Science.gov (United States)

Bachani, A M; Hung, Y W; Mogere, S; Akunga, D; Nyamari, J; Hyder, A A

2017-03-01

In light of the increasing prevalence of motorcycles on Kenyan roads, there is a need to address the safety of individuals using this mode of transport. Helmet use has been proven to be effective in preventing head injuries and fatalities in the event of a crash. This study aims to understand the prevalence of helmet use as well as knowledge, attitudes, and practices in two districts in Kenya over a 5-year period (2010-2014). Observational studies on helmet use at randomly selected locations throughout each district were done every quarter to estimate the prevalence of helmet use. Roadside knowledge, attitude, and practice (KAP) surveys were done two times a year in each district. Helmet use among motorcycle drivers and passengers in Thika and Naivasha was assessed through systematic observations at randomly selected locations in the two districts between August 2010 and December 2014. Roadside KAP surveys were administered in both sites to motorcyclists in areas where they stopped, including motorcycle bays, petrol stations and rest areas near the helmet observation sites. Secondary analysis of trauma registries was also used. Negative binomial regressions were used to assess trends of helmet wearing among motorcyclists over time, and logistic regressions were used to analyze associated risk factors as well as association with health outcomes among those admitted to the four hospitals. A total of 256,851 motorcycles were observed in the two target districts during the study period. Overall, prevalence of helmet use among motorcycle drivers in Thika and Naivasha across all periods was 35.12% (95% confidence interval [CI]: 34.87%-35.38%) and 37.42% (95% CI: 37.15%-37.69%) respectively. Prevalence of helmet wearing remained similar after the passage of a traffic amendment bill. These results were not statistically significant in either Thika or in Naivasha. Data from the KAP survey showed that respondents recognized the life-saving effect of wearing a helmet, but

How Satisfied are Soldiers with their Ballistic Helmets? A Comparison of Soldiers' Opinions about the Advanced Combat Helmet and the Personal Armor System for Ground Troops

National Research Council Canada - National Science Library

Ivins, Brian J; Schwab, Karen; Crowley, John S; McEntire, B. J; Trumble, Christopher C; Brown, Fred H; Warden, Deborah L

2008-01-01

.... These factors affect Soldiers' decisions about helmet use; therefore, rigorous research about Soldiers' real-life experiences with helmets is critical to assessing a helmet's overall protective efficacy...

What do we know about bicycle helmets?

NARCIS (Netherlands)

Bogerd, C.P. Halldin, P. Houtenbos, M. Otte, D. Rossi, R.M. Walker, L. Willinger, R. & Shinar, D.

2012-01-01

Cycling is an excellent sustainable alternative to driving for many journeys. But cyclists have fewer safety options than car-users, with a helmet being the main safety device that is available. However, there are indications that increasing bicycle helmet usage through legislation causes

Enhanced visualization of inner ear structures

Science.gov (United States)

Niemczyk, Kazimierz; Kucharski, Tomasz; Kujawinska, Malgorzata; Bruzgielewicz, Antoni

2004-07-01

Recently surgery requires extensive support from imaging technologies in order to increase effectiveness and safety of operations. One of important tasks is to enhance visualisation of quasi-phase (transparent) 3d structures. Those structures are characterized by very low contrast. It makes differentiation of tissues in field of view very difficult. For that reason the surgeon may be extremly uncertain during operation. This problem is connected with supporting operations of inner ear during which physician has to perform cuts at specific places of quasi-transparent velums. Conventionally during such operations medical doctor views the operating field through stereoscopic microscope. In the paper we propose a 3D visualisation system based on Helmet Mounted Display. Two CCD cameras placed at the output of microscope perform acquisition of stereo pairs of images. The images are processed in real-time with the goal of enhancement of quasi-phased structures. The main task is to create algorithm that is not sensitive to changes in intensity distribution. The disadvantages of existing algorithms is their lack of adaptation to occuring reflexes and shadows in field of view. The processed images from both left and right channels are overlaid on the actual images exported and displayed at LCD's of Helmet Mounted Display. A physician observes by HMD (Helmet Mounted Display) a stereoscopic operating scene with indication of the places of special interest. The authors present the hardware ,procedures applied and initial results of inner ear structure visualisation. Several problems connected with processing of stereo-pair images are discussed.

Differential protective effects of motorcycle helmets against head injury.

Science.gov (United States)

Singleton, Michael D

2017-05-19

Although numerous observational studies have demonstrated a protective effect of motorcycle helmets against head injury, the degree of protection against specific head injury types remains unclear. Experimental biomechanics studies involving cadavers, animals, and computer models have established that head injuries have varying etiologies. This retrospective cross-sectional study compared helmet protection against skull fracture, cerebral contusion, intracranial hemorrhage, and cerebral concussion in a consecutive series of motorcycle operators involved in recent traffic crashes in Kentucky. Police collision reports linked to hospital inpatient and emergency department (ED) claims were analyzed for the period 2008 to 2012. Motorcycle operators with known helmet use who were not killed at the crash scene were included in the study. Helmet use was ascertained from the police report. Skull fracture, cerebral contusion, intracranial hemorrhage, and cerebral concussion were identified from International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes on the claims records. The relative risks of each type of head injury for helmeted versus unprotected operators were estimated using generalized estimating equations. Helmets offer substantial protection against skull fracture (relative risk [RR] = 0.31, 95% confidence interval [CI], 0.23, 0.34), cerebral contusion (RR = 0.29, 95% CI, 0.16, 0.53), and intracranial hemorrhage (RR = 0.47, 95% CI, 0.35, 0.63). The findings pertaining to uncomplicated concussion (RR = 0.80, 95% CI, 0.64, 1.01) were inconclusive. A modest protective effect (20% risk reduction) was suggested by the relative risk estimate, but the 95% confidence interval included the null value. Motorcycle helmets were associated with a 69% reduction in skull fractures, 71% reduction in cerebral contusion, and 53% reduction in intracranial hemorrhage. This study finds that current motorcycle helmets do not protect equally against

Helmet-induced headache among Danish military personnel.

Science.gov (United States)

Rahmani, Zakia; Kochanek, Aneta; Astrup, Jesper Johnsen; Poulsen, Jeppe Nørgaard; Gazerani, Parisa

2017-12-01

External compression headache is defined as a headache caused by an external physical compression applied on the head. It affects about 4% of the general population; however, certain populations (e.g. construction workers and military personnel) with particular needs of headwear or helmet are at higher risk of developing this type of headache. External compression headache is poorly studied in relation to specific populations. This study aimed to investigate the prevalence and pattern of helmet-induced external compression headache among Danish military personnel of the Northern Jutland region in Denmark. Data acquisition was based on a custom-made questionnaire delivered to volunteers who used helmets in the Danish military service and who agreed to participate in this study. The military of the Northern Jutland region of Denmark facilitated recruitment of the participants. The questionnaires were delivered on paper and the collected (anonymous) answers (total 279) were used for further analysis. About 30% of the study participants reported headache in relation to wearing a military helmet. Headache was defined as a pressing pain predominantly in the front of the head with an average intensity of 4 on a visual analogue scale of 0 (no pain) to 10 (worst pain imaginable). It was also found that helmets with different designs influenced both the occurrence of headache and its characteristics. This study is the first to demonstrate the prevalence and pattern of compression headache among military personnel in North Jutland, Denmark. The findings of this study call for further attention to helmet-induced external compression headache and strategies to minimize the burden.

The Effects of Motorcycle Helmet Legislation on Craniomaxillofacial Injuries.

Science.gov (United States)

Adams, Nicholas S; Newbury, Patrick A; Eichhorn, Mitchell G; Davis, Alan T; Mann, Robert J; Polley, John W; Girotto, John A

2017-06-01

Motorcycle helmet legislation has been a contentious topic for over a half-century. Benefits of helmet use in motorcycle trauma patients are well documented. In 2012, Michigan repealed its universal motorcycle helmet law in favor of a partial helmet law. The authors describe the early clinical effects on facial injuries throughout Michigan. Retrospective data from the Michigan Trauma Quality Improvement Program trauma database were evaluated. Included were 4643 motorcycle trauma patients presenting to 29 Level I and II trauma centers throughout Michigan 3 years before and after the law repeal (2009 to 2014). Demographics, external cause of injury codes, International Classification of Diseases, Ninth Revision diagnosis codes, and injury details were gathered. The proportion of unhelmeted trauma patients increased from 20 percent to 44 percent. Compared with helmeted trauma patients, unhelmeted patients were nearly twice as likely to sustain craniomaxillofacial injuries (relative risk, 1.90), including fractures (relative risk, 2.02) and soft-tissue injuries (relative risk, 1.94). Unhelmeted patients had a lower Glasgow Coma Scale score and higher Injury Severity Scores. Patients presenting after helmet law repeal were more likely to sustain craniomaxillofacial injuries (relative risk, 1.46), including fractures (relative risk, 1.28) and soft-tissue injuries (relative risk, 1.56). No significant differences were observed for age, sex, Injury Severity Score, or Glasgow Coma Scale score (p > 0.05). This study highlights the significant negative impact of relaxed motorcycle helmet laws leading to an increase in craniomaxillofacial injuries. The authors urge state and national legislators to reestablish universal motorcycle helmet laws.

Optical gesture sensing and depth mapping technologies for head-mounted displays: an overview

Science.gov (United States)

Kress, Bernard; Lee, Johnny

2013-05-01

Head Mounted Displays (HMDs), and especially see-through HMDs have gained renewed interest in recent time, and for the first time outside the traditional military and defense realm, due to several high profile consumer electronics companies presenting their products to hit market. Consumer electronics HMDs have quite different requirements and constrains as their military counterparts. Voice comments are the de-facto interface for such devices, but when the voice recognition does not work (not connection to the cloud for example), trackpad and gesture sensing technologies have to be used to communicate information to the device. We review in this paper the various technologies developed today integrating optical gesture sensing in a small footprint, as well as the various related 3d depth mapping sensors.

Universal Motorcycle Helmet Laws to Reduce Injuries: A Community Guide Systematic Review.

Science.gov (United States)

Peng, Yinan; Vaidya, Namita; Finnie, Ramona; Reynolds, Jeffrey; Dumitru, Cristian; Njie, Gibril; Elder, Randy; Ivers, Rebecca; Sakashita, Chika; Shults, Ruth A; Sleet, David A; Compton, Richard P

2017-06-01

Motorcycle crashes account for a disproportionate number of motor vehicle deaths and injuries in the U.S. Motorcycle helmet use can lead to an estimated 42% reduction in risk for fatal injuries and a 69% reduction in risk for head injuries. However, helmet use in the U.S. has been declining and was at 60% in 2013. The current review examines the effectiveness of motorcycle helmet laws in increasing helmet use and reducing motorcycle-related deaths and injuries. Databases relevant to health or transportation were searched from database inception to August 2012. Reference lists of reviews, reports, and gray literature were also searched. Analysis of the data was completed in 2014. A total of 60 U.S. studies qualified for inclusion in the review. Implementing universal helmet laws increased helmet use (median, 47 percentage points); reduced total deaths (median, -32%) and deaths per registered motorcycle (median, -29%); and reduced total injuries (median, -32%) and injuries per registered motorcycle (median, -24%). Repealing universal helmet laws decreased helmet use (median, -39 percentage points); increased total deaths (median, 42%) and deaths per registered motorcycle (median, 24%); and increased total injuries (median, 41%) and injuries per registered motorcycle (median, 8%). Universal helmet laws are effective in increasing motorcycle helmet use and reducing deaths and injuries. These laws are effective for motorcyclists of all ages, including younger operators and passengers who would have already been covered by partial helmet laws. Repealing universal helmet laws decreased helmet use and increased deaths and injuries. Published by Elsevier Inc.

Measurement of Gamma Knife registered helmet factors using MOSFETs

International Nuclear Information System (INIS)

Kurjewicz, Laryssa; Berndt, Anita

2007-01-01

The relative dose rate for the different Gamma Knife registered helmets (4, 8, 14, and 18 mm) is characterized by their respective helmet factors. Since the plateau of the dose profile for the 4 mm helmet is at most 1 mm wide, detector choices are limited. Traditionally helmet factors have been measured using 1x1x1 mm 3 thermoluminescent dosimeters (TLDs). However, these are time-consuming, cumbersome measurements. This article investigates the use of metal-oxide-semiconductor field effect transistors (MOSFETs) (active area of 0.2x0.2 mm 2 ) as a more accurate and convenient dosimeter. Their suitability for these measurements was confirmed by basic characterization measurements. Helmet factors were measured using both MOSFETs and the established TLD approach. A custom MOSFET cassette was designed in analogy to the Elekta TLD cassette (Elekta Instruments AB) for use with the Elekta dosimetry sphere. Although both dosimeters provided values within 3% of the manufacturer's suggestion, MOSFETs provided superior accuracy and precision, in a fraction of the time required for the TLD measurements. Thus, MOSFETs proved to be a reasonable alternative to TLDs for performing helmet factor measurements

Passengers' attitudes and behaviour towards motorcycle helmet use ...

African Journals Online (AJOL)

Passengers' attitudes and behaviour towards motorcycle helmet use in Ilorin, ... Remember me ... The purpose of this study was to examine the attitudes, knowledge, and behavior of motorcycle passengers to helmet use in Ilorin metropolis, ...

How motorcycle helmets affect trauma mortality: Clinical and policy implications.

Science.gov (United States)

Lee, Jwo-Leun; Chen, Tzu-Chun; Huang, Hung-Chang; Chen, Ray-Jade

2017-08-18

Motorcycles are the most popular vehicles in Taiwan, where more than 14.8 million motorcycles (1 motorcycle per 1.6 people) are in service. Despite the mandatory helmet law passed in 1997, less than 80% of motorcyclists in Taiwan wear helmets. The objective of this study was to analyze the effect of using motorcycle helmets on fatality rates. A clinical data set including 2,868 trauma patients was analyzed; the cross-sectional registration database was administered by a university medical center in Central Taiwan. A path analysis framework and multiple logistic regressions were used to estimate the marginal effect of helmet use on mortality. Using a helmet did not directly reduce the mortality rate but rather indirectly reduced the mortality rate through intervening variables such as the severity of head injuries, number of craniotomies, and complications during therapeutic processes. Wearing a helmet can reduce the fatality rate by 1.3%, the rate of severe head injury by 34.5%, the craniotomy rate by 7.8%, and the rate of complications during therapeutic processes by 1.5%. These rates comprise 33.3% of the mortality rate for people who do not wear helmets, 67.3% of the severe head injury rate, 60.0% of the craniotomy rate, and 12.2% of the rate of complications during therapeutic processes. Wearing a helmet and trauma system designation are crucial factors that reduce the fatality rate.

Does law enforcement awareness affect motorcycle helmet use? evidence from urban cities in Thailand.

Science.gov (United States)

Jiwattanakulpaisarn, Piyapong; Kanitpong, Kunnawee; Ponboon, Sattrawut; Boontob, Nuttapong; Aniwattakulchai, Pakorn; Samranjit, Supattra

2013-09-01

Although helmet use has been compulsory for motorcycle drivers and passengers in Thailand since the enactment of the Helmet Act in 1994, recent surveys show that the prevalence of helmet usage remains low, particularly among passengers. This paper has sought to explore motorcyclists' awareness of helmet law enforcement in Thailand and examine whether it affects their helmet use behaviour. A total of 2,429 drivers and 1,328 passengers in urban cities nationwide were interviewed in 2009, and the data were analysed using a multivariate ordered logit regression technique. About 60% of the drivers and only 28% of the passengers reported that they always wore a motorcycle helmet. Apart from basic demographics (i.e. age and gender) and riding frequency, our analysis reveals that the awareness of helmet law enforcement was among the contributing factors influencing the use of motorcycle helmets in Thailand. Regardless of riding position, the prevalence of helmet use tended to be greater among those frequently observing the police's checkpoints for helmet wearing and those perceiving the high risk of being caught for non-helmet use. However, the use of helmets appeared to be lower among drivers who perceived the checkpoints to take place at the same times and locations, which were likely predicted. For motorcycle passengers, it was found that the low prevalence of helmet use was potentially attributable to the absence of knowledge on the compulsory helmet law for passengers and the perception that the law was not enforced by the police. Thus, if motorcycle helmet use in Thailand is to be increased, considerable efforts need to be given to increasing the perceived risk of apprehension for non-helmet use (e.g. more police presence and random scheduling of enforcement activities), improving the awareness of the existing helmet law for passengers, and ensuring that helmet wearing by passengers is more strictly enforced.

Development of a surgical navigation system based on augmented reality using an optical see-through head-mounted display.

Science.gov (United States)

Chen, Xiaojun; Xu, Lu; Wang, Yiping; Wang, Huixiang; Wang, Fang; Zeng, Xiangsen; Wang, Qiugen; Egger, Jan

2015-06-01

The surgical navigation system has experienced tremendous development over the past decades for minimizing the risks and improving the precision of the surgery. Nowadays, Augmented Reality (AR)-based surgical navigation is a promising technology for clinical applications. In the AR system, virtual and actual reality are mixed, offering real-time, high-quality visualization of an extensive variety of information to the users (Moussa et al., 2012) [1]. For example, virtual anatomical structures such as soft tissues, blood vessels and nerves can be integrated with the real-world scenario in real time. In this study, an AR-based surgical navigation system (AR-SNS) is developed using an optical see-through HMD (head-mounted display), aiming at improving the safety and reliability of the surgery. With the use of this system, including the calibration of instruments, registration, and the calibration of HMD, the 3D virtual critical anatomical structures in the head-mounted display are aligned with the actual structures of patient in real-world scenario during the intra-operative motion tracking process. The accuracy verification experiment demonstrated that the mean distance and angular errors were respectively 0.809±0.05mm and 1.038°±0.05°, which was sufficient to meet the clinical requirements. Copyright © 2015 Elsevier Inc. All rights reserved.

Usability Comparisons of Head-Mounted vs. Stereoscopic Desktop Displays in a Virtual Reality Environment with Pain Patients.

Science.gov (United States)

Tong, Xin; Gromala, Diane; Gupta, Dimple; Squire, Pam

2016-01-01

Researchers have shown that immersive Virtual Reality (VR) can serve as an unusually powerful pain control technique. However, research assessing the reported symptoms and negative effects of VR systems indicate that it is important to ascertain if these symptoms arise from the use of particular VR display devices, particularly for users who are deemed "at risk," such as chronic pain patients Moreover, these patients have specific and often complex needs and requirements, and because basic issues such as 'comfort' may trigger anxiety or panic attacks, it is important to examine basic questions of the feasibility of using VR displays. Therefore, this repeated-measured experiment was conducted with two VR displays: the Oculus Rift's head-mounted display (HMD) and Firsthand Technologies' immersive desktop display, DeepStream3D. The characteristics of these immersive desktop displays differ: one is worn, enabling patients to move their heads, while the other is peered into, allowing less head movement. To assess the severity of physical discomforts, 20 chronic pain patients tried both displays while watching a VR pain management demo in clinical settings. Results indicated that participants experienced higher levels of Simulator Sickness using the Oculus Rift HMD. However, results also indicated other preferences of the two VR displays among patients, including physical comfort levels and a sense of immersion. Few studies have been conducted that compare usability of specific VR devices specifically with chronic pain patients using a therapeutic virtual environment in pain clinics. Thus, the results may help clinicians and researchers to choose the most appropriate VR displays for chronic pain patients and guide VR designers to enhance the usability of VR displays for long-term pain management interventions.

Helmet Ownership and Use among Skateboarders: Utilisation of the Health Belief Model

Science.gov (United States)

Peachey, Andrew A.; Sutton, Debra L.; Cathorall, Michelle L.

2016-01-01

Introduction: The purpose of this study was to determine the proportion of skateboarders who owned and who wore a helmet and which constructs from the Health Belief Model predicted helmet ownership and helmet use among undergraduate skateboarders. Methods: From March 2013 through March 2014, 83 skateboarders completed a helmet attitude and use…

Optimizing height presentation for aircraft cockpit displays

Science.gov (United States)

Jordan, Chris S.; Croft, D.; Selcon, Stephen J.; Markin, H.; Jackson, M.

1997-02-01

This paper describes an experiment conducted to investigate the type of display symbology that most effectively conveys height information to users of head-down plan-view radar displays. The experiment also investigated the use of multiple information sources (redundancy) in the design of such displays. Subjects were presented with eight different height display formats. These formats were constructed from a control, and/or one, two, or three sources of redundant information. The three formats were letter coding, analogue scaling, and toggling (spatially switching the position of the height information from above to below the aircraft symbol). Subjects were required to indicate altitude awareness via a four-key, forced-choice keyboard response. Error scores and response times were taken as performance measures. There were three main findings. First, there was a significant performance advantage when the altitude information was presented above and below the symbol to aid the representation of height information. Second, the analogue scale, a line whose length indicated altitude, proved significantly detrimental to performance. Finally, no relationship was found between the number of redundant information sources employed and performance. The implications for future aircraft and displays are discussed in relation to current aircraft tactical displays and in the context of perceptual psychological theory.

Camouflage design and head measurement characteristic of Indonesian armoured vehicle helmet

Science.gov (United States)

Sya'bana, Yukhi Mustaqim Kusuma; Sanjaya, K. H.

2017-01-01

In this paper discussed camouflage design helmet for armored vehicles with comparing head measurement of Indonesian anthropometric. Design process conduct with considering of design aspects involves function, materials, operational, technology, user, and appearance (camouflage). As an application of Indonesian National Army that qualifies factors needs: safety, comfort, practical and service. MIL-H-44099A Military Specification: Helmet, Ground Troops And Parachutists is minimum limitation standard of military helmet production. Head measurement for product design process guide is presented. Model simulation and helmet measurement using the design for ego and design for more types ergonomics concept. Appearance shape concept is engaging camouflage towards background and environment to deceive enemy viewpoint. Helmet prototype has tested ergonomically to an Indonesian National Army soldier and stated that the helmet size is a comfort and fitted on the head when in use.

Long-term use of neonatal helmet-CPAP: a case report.

Science.gov (United States)

Doglioni, N; Micaglio, M; Zanardo, V; Trevisanuto, D

2009-12-01

In a recent short-term physiological study, we demonstrated a new continuous positive airway pressure (CPAP) system (neonatal helmet-CPAP) that could be a feasible device for managing preterm infants needing continuous distending pressure with better tolerability than nasal-CPAP. However, its application for a long-term period has never been reported in neonates. Here, we describe the use of neonatal helmet-CPAP in a neonate with persistent pulmonary hypertension of the newborn. Twenty minutes after neonatal helmet-CPAP placement, the baseline post-ductal tcSaO2 (66%) and alveolar-arterial gradient O2 improved from 66% and 648 mmHg to 100% and 465 mmHg, respectively. The neonatal helmet-CPAP was applied for 48 hours and was well-tolerated by the patient without complications. Long-term use of neonatal helmet-CPAP appears feasible and well-tolerated. Comparative trials are needed.

Paternalism & Its Discontents: Motorcycle Helmet Laws, Libertarian Values, and Public Health

Science.gov (United States)

Jones, Marian Moser; Bayer, Ronald

2007-01-01

The history of motorcycle helmet legislation in the United States reflects the extent to which concerns about individual liberties have shaped the public health debate. Despite overwhelming epidemiological evidence that motorcycle helmet laws reduce fatalities and serious injuries, only 20 states currently require all riders to wear helmets. During the past 3 decades, federal government efforts to push states toward enactment of universal helmet laws have faltered, and motorcyclists’ advocacy groups have been successful at repealing state helmet laws. This history raises questions about the possibilities for articulating an ethics of public health that would call upon government to protect citizens from their own choices that result in needless morbidity and suffering. PMID:17194856

Helmet use and associated factors among motorcyclists in the ...

African Journals Online (AJOL)

opperwjj

in Malaysia and the highest (10) in Brunei Duressalam. Stricter .... in line with the global findings that the introduction and enforcement of legislation on helmet .... Motorcycle helmet wearing behavior among Naresuan university students.

A head-mounted display-based personal integrated-image monitoring system for transurethral resection of the prostate.

Science.gov (United States)

Yoshida, Soichiro; Kihara, Kazunori; Takeshita, Hideki; Fujii, Yasuhisa

2014-12-01

The head-mounted display (HMD) is a new image monitoring system. We developed the Personal Integrated-image Monitoring System (PIM System) using the HMD (HMZ-T2, Sony Corporation, Tokyo, Japan) in combination with video splitters and multiplexers as a surgical guide system for transurethral resection of the prostate (TURP). The imaging information obtained from the cystoscope, the transurethral ultrasonography (TRUS), the video camera attached to the HMD, and the patient's vital signs monitor were split and integrated by the PIM System and a composite image was displayed by the HMD using a four-split screen technique. Wearing the HMD, the lead surgeon and the assistant could simultaneously and continuously monitor the same information displayed by the HMD in an ergonomically efficient posture. Each participant could independently rearrange the images comprising the composite image depending on the engaging step. Two benign prostatic hyperplasia (BPH) patients underwent TURP performed by surgeons guided with this system. In both cases, the TURP procedure was successfully performed, and their postoperative clinical courses had no remarkable unfavorable events. During the procedure, none of the participants experienced any HMD-wear related adverse effects or reported any discomfort.

Prehospital emergency removal of football helmets using two techniques.

Science.gov (United States)

Swartz, Erik E; Hernandez, Adam E; Decoster, Laura C; Mihalik, Jason P; Burns, Matthew F; Reynolds, Cathryn

2011-01-01

To compare the Eject Helmet Removal (EHR) System with manual football helmet removal. This quasiexperimental counterbalanced study was conducted in a controlled laboratory setting. Thirty certified athletic trainers (17 men and 13 women; mean ± standard deviation age: 33.03 ± 10.02 years; height: 174.53 ± 12.04 cm; mass: 85.19 ± 19.84 kg) participated after providing informed consent. Participants removed a Riddell Revolution IQ football helmet from a healthy model two times each under two conditions: manual helmet removal (MHR) and removal with the EHR system. A six-camera, three-dimensional motion capture system was used to record range of motion (ROM) of the head. A digital stopwatch was used to time trials and to record a split time associated with EHR system bladder insertion. A modified Borg CR10 scale was used to measure the rating of perceived exertion (RPE). Mean values were created for each variable. Three pairwise t-tests with Bonferroni-corrected alpha levels tested for differences between time for removal, split time, and RPE. A 2 x 3 (condition x plane) totally within-subjects repeated-measures design analysis of variance (ANOVA) tested for differences in head ROM between the sagittal, frontal, and transverse planes. Analyses were performed using SPSS (version 18.0) (alpha = 0.05). There was no statistically significant difference in perceived difficulty between EHR (RPE = 2.73) and MHR (RPE = 2.55) (t(29) = 0.76; p = 0.45; d = 0.20). Manual helmet removal was, on average, 28.95 seconds faster than EHR (t(29) = 11.44; p football helmets and in helmets used in other sports such as lacrosse, motorsports, and ice hockey.

Amblyopia treatment of adults with dichoptic training using the virtual reality oculus rift head mounted display: preliminary results

OpenAIRE

Žiak, Peter; Holm, Anders; Halička, Juraj; Mojzis, Peter; Piñero, David P.

2017-01-01

Background The gold standard treatments in amblyopia are penalizing therapies, such as patching or blurring vision with atropine that are aimed at forcing the use of the amblyopic eye. However, in the last years, new therapies are being developed and validated, such as dichoptic visual training, aimed at stimulating the amblyopic eye and eliminating the interocular supression. Purpose To evaluate the effect of dichoptic visual training using a virtual reality head mounted display in a sample ...

Position display device

International Nuclear Information System (INIS)

Nishizawa, Yukio.

1974-01-01

Object: To provide a device capable of easily and quickly reading mutual mounting relations of control bodies such as control rods mounted on a nuclear reactor and positions to which the control bodies are driven. Structure: A scanning circuit is provided to scan positions of controllably mounted control bodies such as control rods. Values detected by scanning the positions are converted into character signals according to the values and converted into preranked color signals. The character signals and color signals are stored in a memory circuit by synchronous signals in synchronism with the scanning in the scanning circuit. Outputs of the memory circuit are displayed by a display unit such as a color Braun tube in accordance with the synchronous signals to provide color representations according to positions to which control bodies are driven in the same positional relation as the mounting of the control bodies. (Kamimura, M.)

Capabilities of Helmets for Preventing Head Injuries Induced by Ballistic Impacts

Directory of Open Access Journals (Sweden)

D.V. Balandin

2004-01-01

Full Text Available The limiting performance of ballistically loaded helmets designed to reduce head injuries is studied analytically. The projectile does not penetrate the helmet. This analysis evaluates the absolute minimum of the peak displacement of the helmet shell relative to the head, provided that criteria measuring the severity of head injuries lie within prescribed limits. Rather than optimize a specific design configuration, e.g. a viscoelastic foam liner, characteristics of a time-dependent force representing the helmet liner are calculated. The formulation reduces the limiting performance analysis to an optimal control problem.

Optical methods for enabling focus cues in head-mounted displays for virtual and augmented reality

Science.gov (United States)

Hua, Hong

2017-05-01

Developing head-mounted displays (HMD) that offer uncompromised optical pathways to both digital and physical worlds without encumbrance and discomfort confronts many grand challenges, both from technological perspectives and human factors. Among the many challenges, minimizing visual discomfort is one of the key obstacles. One of the key contributing factors to visual discomfort is the lack of the ability to render proper focus cues in HMDs to stimulate natural eye accommodation responses, which leads to the well-known accommodation-convergence cue discrepancy problem. In this paper, I will provide a summary on the various optical methods approaches toward enabling focus cues in HMDs for both virtual reality (VR) and augmented reality (AR).

Inadequate Helmet Fit Increases Concussion Severity in American High School Football Players.

Science.gov (United States)

Greenhill, Dustin A; Navo, Paul; Zhao, Huaqing; Torg, Joseph; Comstock, R Dawn; Boden, Barry P

2016-05-01

There is limited information on the relationship between football helmet fit and concussion severity. Poor helmet fit may predispose football players to a more severe concussion. Descriptive epidemiology study. Level 3. Data from concussion injury reports were obtained from the National High School Sports-Related Injury Surveillance System over a 9-year period. Symptoms, duration, and helmet parameters (fit, interior padding) were analyzed for all first-time concussions. Data from 4580 concussions were analyzed. Patients who suffered concussions with a helmet that did not fit properly (3.22%), as determined by an athletic trainer, had higher rates of drowsiness (RR, 1.46; P = 0.005), hyperexcitability (RR, 2.38; P = 0.047), and sensitivity to noise (RR, 1.88; P football helmet is a risk factor for a concussion with more symptoms and of longer duration. Concussions of longer duration are also more common in players with an air bladder-lined helmet. Current high school football rules should mandate supervision and maintenance of helmet fit throughout the season, prior to impact. Team physicians, athletic trainers, coaches, and high school officials should ensure proper oversight of helmet fit in high school athletes to decrease concussion severity and duration. © 2016 The Author(s).

Viet Nam’s mandatory motorcycle helmet law and its impact on children

Science.gov (United States)

Pervin, Aaron; Sidik, Mirjam; McKinley, Tyler; Tu, Nguyen Thi Hong; Nam, Nguyen Phuong

2009-01-01

Abstract Objective To measure the use of motorcycle helmets in children and to determine the reasons why children wear helmets less often than adults. Methods The frequency of helmet wearing among adults and children was ascertained by trained roadside observers, and randomized road user surveys were completed in four major centres in Viet Nam: Hanoi, Ho Chi Minh City, Can Tho and Da Nang. Survey data on key questions were cross tabulated, and χ² was calculated for significant differences between parents and non-parents (0.05). Findings The frequency of helmet use in the four study locations ranged from 90–99% among adults, from 15–53% among children ≤ 7 years of age, and from 38–53% among children > 7 but ≤ 14. Of the parents surveyed, 67% said the fear of neck injury was the most important reason their children did not wear a helmet. Conclusion Children wear motorcycle helmets much less often than adults. Legislation to penalize adults whose children do not wear motorcycle helmets has been proposed in Viet Nam. Furthermore, ongoing advocacy and social marketing efforts are being made to disseminate information about the safety benefits of helmets to combat erroneous public perceptions. PMID:19551255

In defence of mandatory bicycle helmet legislation: response to Hooper and Spicer.

Science.gov (United States)

Biegler, Paul; Johnson, Marilyn

2015-08-01

We invoke a triple rationale to rebut Hooper and Spicer's argument against mandatory helmet laws. First, we use the laws of physics and empirical studies to show how bicycle helmets afford substantial protection to the user. We show that Hooper and Spicer erroneously downplay helmet utility and that, as a result, their attack on the utilitarian argument for mandatory helmet laws is weakened. Next, we refute their claim that helmet legislation comprises unjustified paternalism. We show the healthcare costs of bareheaded riding to pose significant third party harms. It follows, we argue, that a utilitarian case for helmet laws can be sustained by appeal to Mill's Harm Principle. Finally, we reject Hooper and Spicer's claim that helmet laws unjustly penalise cyclists for their own health-affecting behaviour. Rather, we show their argument to suffer by disanalogy with medical cases where injustice may be more evident, for example, denial of bypass surgery to smokers. We conclude that mandatory helmet laws offer substantial utility and are entirely defensible within the framework of a liberal democracy. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Evaluating the image quality of Closed Circuit Television magnification systems versus a head-mounted display for people with low vision. .

Science.gov (United States)

Lin, Chern Sheng; Jan, Hvey-An; Lay, Yun-Long; Huang, Chih-Chia; Chen, Hsien-Tse

2014-01-01

In this research, image analysis was used to optimize the visual output of a traditional Closed Circuit Television (CCTV) magnifying system and a head-mounted display (HMD) for people with low vision. There were two purposes: (1) To determine the benefit of using an image analysis system to customize image quality for a person with low vision, and (2) to have people with low vision evaluate a traditional CCTV magnifier and an HMD, each customized to the user's needs and preferences. A CCTV system can electronically alter images by increasing the contrast, brightness, and magnification for the visually disabled when they are reading texts and pictures. The test methods was developed to evaluate and customize a magnification system for persons with low vision. The head-mounted display with CCTV was used to obtain better depth of field and a higher modulation transfer function from the video camera. By sensing the parameters of the environment (e.g., ambient light level, etc.) and collecting the user's specific characteristics, the system could make adjustments according to the user's needs, thus allowing the visually disabled to read more efficiently.

Finite element modelling of helmeted head impact under frontal ...

Indian Academy of Sciences (India)

helmets in direct impact are well documented and helmets have been found to ... conditions during a drop test and studied the influence of shell stiffness and liner ... the latter authors use a SI (Structural Intensity) approach to study power flow ...

The problem of the pillion rider: India's helmet law and New Delhi's exemption.

Science.gov (United States)

Swaroop, Mamta; Marie Siddiqui, Selma; Sagar, Sushma; Crandall, Marie L

2014-05-01

In India, motorized two-wheeler (MTW) road traffic accidents injure or kill 72,000 women annually. Before the Motor Vehicle Act of 1988, which required mandatory helmet use for MTW riders, a study found 0.6% of all MTW pillions (backseat passengers) were helmeted. Citing religious protests to the legislation, Delhi's high court exempted the city's 12 million women from the law. We hypothesize that currently male pillions use helmets more frequently than females, and that overall pillion helmet usage has increased over the last 20 y. Continuous video was recorded in half-hour blocks at four locations in Delhi on separate days, totaling 8 hours of high- and low-volume traffic. Videos were reviewed with at least two reviewers extracting the number of MTW pillions, as well as their gender, approximate age, and helmet usage. Of 4010 pillions identified, 63.8% were male, 32.4% female, and 3.3% children. Among males, there were significantly more helmeted pillions (88.4%, P < 0.001); among females, there were significantly more unhelmeted pillions (99.4%, P < 0.001). Among unhelmeted pillions, significantly more were female (81.4%) than male (P < 0.001). Current overall pillion helmet use is significantly higher than historical rate (P < 0.001). The significantly higher male pillion helmet usage compared with females indicates Delhi's helmet law is associated with increased compliance among those who fall under its jurisdiction. This augments the growing body of evidence that mandatory helmet laws are efficacious, thus repealing the exemption of women is an important step in increasing female pillion helmet usage. Copyright © 2014 Elsevier Inc. All rights reserved.

Neutron and X-ray characterisation of the metallurgical properties of a 7th century BC Corinthian-type bronze helmet

Science.gov (United States)

Pantos, E.; Kockelmann, W.; Chapon, L. C.; Lutterotti, L.; Bennet, S. L.; Tobin, M. J.; Mosselmans, J. F. W.; Pradell, T.; Salvado, N.; Butí, S.; Garner, R.; Prag, A. J. N. W.

2005-09-01

Neutron and synchrotron X-ray diffraction, X-ray fluorescence and FTIR were used to examine a Corinthian-type bronze helmet which is now on display at The Manchester Museum, UK. This type of helmet was manufactured out of a single piece of bronze, probably on a rod-anvil, and like all body-armour it was made to measure. Neutron diffraction sampling of the bronze volume in different areas was used to study the composition, microstructure and crystallographic texture of the alloy in order to draw conclusions about the manufacturing processes. The neutron data revealed the presence of microstrains and non-random distributions of bronze grains hinting at annealing-hammering working cycles in order to harden and shape the alloy. X-ray fluorescence showed that the main body of the helmet is a copper-tin alloy, while the noseguard contains zinc in high abundance. This key compositional difference confirms that the noseguard is not the original but is a modern substitute fabricated for restoration purposes. SR XRD and FTIR from several spots on the head and noseguard identified several surface corrosion products and showed a variation of the Cu-Sn or Cu-Zn percentage compositions, and of the mineral phases. Small samples of corrosion flakes extracted from the outside and inside of the helmet were used to obtain powder XRD patterns.

Neck Muscle Fatigue Resulting from Prolonged Wear of Weighted Helmets

National Research Council Canada - National Science Library

Gallagher, Hilary L; Caldwell, Erin; ALbery, Christopher B

2008-01-01

.... While these systems undoubtedly increase a pilot's capabilities, one obvious drawback to putting all this equipment on the pilot's helmet is the increase in helmet weight that shifts the combined...

Paternalism and its discontents: motorcycle helmet laws, libertarian values, and public health.

Science.gov (United States)

Jones, Marian Moser; Bayer, Ronald

2007-02-01

The history of motorcycle helmet legislation in the United States reflects the extent to which concerns about individual liberties have shaped the public health debate. Despite overwhelming epidemiological evidence that motorcycle helmet laws reduce fatalities and serious injuries, only 20 states currently require all riders to wear helmets. During the past 3 decades, federal government efforts to push states toward enactment of universal helmet laws have faltered, and motorcyclists' advocacy groups have been successful at repealing state helmet laws. This history raises questions about the possibilities for articulating an ethics of public health that would call upon government to protect citizens from their own choices that result in needless morbidity and suffering.

Characteristics of helmet or knit cap use in head injury of snowboarders.

Science.gov (United States)

Fukuda, Osamu; Hirashima, Yutaka; Origasa, Hideki; Endo, Shunro

2007-11-01

The rate of head injury is 1.86-6 times higher for snowboarding than for skiing. Detailed data about the usefulness of a helmet or knit cap for protecting against serious head injuries have not been reported. The present study evaluated the use of a helmet or knit cap for preventing head injuries. Questionnaire data were collected from 1,190 consecutive patients in a hospital during the 1999/2000-2002/2003 winter seasons at Uonuma ski resort, Niigata, Japan. Patients were divided into the helmet, knit cap, and no cap groups. Upper technical level was highest and jumping as the cause of injury was most frequent in the helmet group. After adjustment for other confounders, there was a significant negative association between the occurrence of serious head injury during snowboarding and female sex (adjusted odds ratio 0.55, 95% confidence interval 0.421-0.718, p jumping (adjusted odds ratio 2.25, 95% confidence interval 1.48-3.43, p = 0.0001). Among snowboarding maneuvers, only jumping showed a significant negative association between wearing of a helmet or knit cap and the occurrence of serious head injury (p = 0.036). Snowboarders who wear helmets might attempt dangerous maneuvers causing injuries. Wearing of a helmet or knit cap protected against serious head injuries on jumping. Every snowboarder should wear a helmet or knit cap on jumping to prevent head injury.

High School Football Players Use Their Helmets to Tackle Other Players Despite Knowing the Risks.

Science.gov (United States)

Kuriyama, Andrew M; Nakatsuka, Austin S; Yamamoto, Loren G

2017-03-01

There is greater attention to head-related injuries and concussions in American football. The helmet's structural safety and the way that football players use their helmets are important in preventing head injuries. Current strategies include penalizing players for high-risk behavior such as leading with their helmet or hitting an opposing player above the shoulder. Passive strategies include helmet modification to better protect the head of the players or to change the playing style of the players. Hawai'i high school varsity football players were surveyed to determine how they use their helmets and how a new helmet design would affect their style of play. One hundred seventy-seven surveys were completed; 79% said that they used their helmet to hit an opposing player during a tackle and 46% said they made this contact intentionally. When asked about modifying helmets with a soft material on the outside, 48% said they thought putting a soft cover over a regular helmet would protect their head better. However, many participants said that putting a soft cover over their regular helmet was a bad idea for various reasons. Most young football players use their helmets to block or tackle despite being taught they would be penalized or potentially injured if they did so. By gaining a better understanding of why and how players use their helmets and how they would respond to new helmet designs, steps can be taken to reduce head injuries for all levels of play.

The effects of motorcycle helmets on hearing and the detection of warning signals

Science.gov (United States)

Van Moorhem, W. K.; Shepherd, K. P.; Magleby, T. D.; Torian, G. E.

1981-07-01

Measurements of the at-ear helmet-generated aerodynamic noise and helmet insertion loss were carried out for the two major types of motorcycle helmets. From these data and existing information on noise generation by flow around a bare head it was found that for quiet motorcycles at typical operating speeds a significant part of the riders at-ear noise is generated by the air flow. An assessment of the possibility of hearing damage was then carried out. It was found that only with extremely high usage would there be a significant risk of hearing damage for either the bare headed or helmeted rider. Helmets did, however, give significant protection. Detection of warning signals was then considered. It was found that under none of the conditions investigated here did the helmet put its wearer at a disadvantage compared with the bare headed rider, and at typical constant speeds the helmet gave a rider an advantage in the detection of warning signals.

The Influence of Friction Between Football Helmet and Jersey Materials on Force: A Consideration for Sport Safety.

Science.gov (United States)

Rossi, Anthony M; Claiborne, Tina L; Thompson, Gregory B; Todaro, Stacey

2016-09-01

The pocketing effect of helmet padding helps to dissipate forces experienced by the head, but if the player's helmet remains stationary in an opponent's shoulder pads, the compressive force on the cervical spine may increase. To (1) measure the coefficient of static friction between different football helmet finishes and football jersey fabrics and (2) calculate the potential amount of force on a player's helmet due to the amount of friction present. Cross-sectional study. Laboratory. Helmets with different finishes and different football jersey fabrics. The coefficient of friction was determined for 2 helmet samples (glossy and matte), 3 football jerseys (collegiate, high school, and youth), and 3 types of jersey numbers (silkscreened, sublimated, and stitched on) using the TAPPI T 815 standard method. These measurements determined which helmet-to-helmet, helmet-to-jersey number, and helmet-to-jersey material combination resulted in the least amount of static friction. The glossy helmet versus glossy helmet combination produced a greater amount of static friction than the other 2 helmet combinations (P = .013). The glossy helmet versus collegiate jersey combination produced a greater amount of static friction than the other helmet-to-jersey material combinations (P < .01). The glossy helmet versus silkscreened numbers combination produced a greater amount of static friction than the other helmet-to-jersey number combinations (P < .01). The force of static friction experienced during collisions can be clinically relevant. Conditions with higher coefficients of static friction result in greater forces. In this study, the highest coefficient of friction (glossy helmet versus silkscreened number) could increase the forces on the player's helmet by 3553.88 N when compared with other helmet-to-jersey combinations. Our results indicate that the makeup of helmet and uniform materials may affect sport safety.

Brain tissue analysis of impacts to American football helmets.

Science.gov (United States)

Post, Andrew; Kendall, Marshall; Cournoyer, Janie; Karton, Clara; Oeur, R Anna; Dawson, Lauren; Hoshizaki, T Blaine

2018-02-01

Concussion in American football is a prevalent concern. Research has been conducted examining frequencies, location, and thresholds for concussion from impacts. Little work has been done examining how impact location may affect risk of concussive injury. The purpose of this research was to examine how impact site on the helmet and type of impact, affects the risk of concussive injury as quantified using finite element modelling of the human head and brain. A linear impactor was used to impact a helmeted Hybrid III headform in several locations and using centric and non-centric impact vectors. The resulting dynamic response was used as input for the Wayne State Brain Injury Model to determine the risk of concussive injury by utilizing maximum principal strain as the predictive variable. The results demonstrated that impacts that occur primarily to the side of the head resulted in higher magnitudes of strain in the grey and white matter, as well as the brain stem. Finally, commonly worn American football helmets were used in this research and significant risk of injury was incurred for all impacts. These results suggest that improvements in American football helmets are warranted, in particular for impacts to the side of the helmet.

Implementation of an all-ages mandatory helmet policy for ice skating.

Science.gov (United States)

Thibault-Halman, Ginette; Fenerty, Lynne; Wheadon-Hore, Kathie; Walling, Simon; Cusimano, Michael D; Clarke, David B

2015-12-01

Ice skaters sustain a significant number of head injuries each winter. We are the first to implement an all-ages helmet policy at a university-based Canadian arena. We report our experience from a cross-sectional observational study as well as the policy's consequences on helmet use and skating participation. Educational programming was provided prior to policy implementation. Observations of helmet use, falls and skater demographics were conducted prior to education/implementation and after policy implementation. The number of skaters observed was essentially unchanged by the policy; 361 skaters were observed pre-implementation, while 358 were observed post-implementation during the same number of observation-hours. Pre-implementation, helmet use ranged from 97% among children under 12 to 10% among adults; post-implementation use in all skaters was 99%. Falls were observed among all age groups, with preponderance among those aged 4-12. An all-ages helmet policy was successful both in achieving helmet use among all skaters and in maintaining participation rates. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Helmet Use and Associated Factors among Thai Motorcyclists during Songkran Festival

Science.gov (United States)

Siviroj, Penprapa; Peltzer, Karl; Pengpid, Supa; Morarit, Sompong

2012-01-01

The aim of this study was to assess helmet use and associated factors among motorcycle riders during Songkran festival in Thailand. A cross-sectional survey was conducted to determine the prevalence of helmet use among Thai motorcycle riders (sample size = 18,998) during four days of the Songkran festival. For this sample, the population of motorcycle riders was consecutively selected using quota sampling from 12 petrol stations in four provinces from each of the four main geographical regions of Thailand. The study was conducted at petrol stations at roads in town, outside town and highway at different time intervals when trained field staff administered a structured questionnaire and performed an observation checklist. Results indicate that 44.2% of the motorcycle riders and 72.5% of the motorcycle passengers had not been using a helmet. In multivariable analysis demographics, environmental factors, helmet use experiences and attitudes and recalling a lower exposure to road safety awareness (RSA) campaign were associated with non-helmet use among motorcyclists. It appears that the RSA campaign may have some positive effect on reducing non-helmet use among motorcycle riders during the Songkran festival. PMID:23202686

DETECTION OF MOTORCYCLISTS WITHOUT HELMET AND FINEPAYMENT USING OPEN CV

OpenAIRE

Stemy Simon, Divya Kumaran A.K.

2018-01-01

The helmet is the main safety equipment of motorcyclists, but many drivers do not use it. The main aim of this project is to construct an automatic detection of the motorcyclist without helmet from video using OpenCV library tools. If they are not wearing the helmet, the license plate of the motorcycle is focused automatically. By using Computer Vision technique we can detect and recognize the license plate number. We make the training set of different characters of different sizes. Based on ...

Inadequate Helmet Fit Increases Concussion Severity in American High School Football Players

Science.gov (United States)

Greenhill, Dustin A.; Navo, Paul; Zhao, Huaqing; Torg, Joseph; Comstock, R. Dawn; Boden, Barry P.

2016-01-01

Background: There is limited information on the relationship between football helmet fit and concussion severity. Hypothesis: Poor helmet fit may predispose football players to a more severe concussion. Study Design: Descriptive epidemiology study. Level of Evidence: Level 3. Methods: Data from concussion injury reports were obtained from the National High School Sports-Related Injury Surveillance System over a 9-year period. Symptoms, duration, and helmet parameters (fit, interior padding) were analyzed for all first-time concussions. Results: Data from 4580 concussions were analyzed. Patients who suffered concussions with a helmet that did not fit properly (3.22%), as determined by an athletic trainer, had higher rates of drowsiness (RR, 1.46; P = 0.005), hyperexcitability (RR, 2.38; P = 0.047), and sensitivity to noise (RR, 1.88; P < 0.001); had more symptoms (5.34 vs 4.54, P = 0.004); and had longer symptom duration (P = 0.04). Athletes with helmets lined with an air bladder had greater rates of sensitivity to light (RR, 1.13; P = 0.02), sensitivity to noise (RR, 1.25; P = 0.009), and longer symptom duration (P = 0.004) compared with foam or gel liners. Conclusion: An improperly fitted football helmet is a risk factor for a concussion with more symptoms and of longer duration. Concussions of longer duration are also more common in players with an air bladder–lined helmet. Current high school football rules should mandate supervision and maintenance of helmet fit throughout the season, prior to impact. Clinical Relevance: Team physicians, athletic trainers, coaches, and high school officials should ensure proper oversight of helmet fit in high school athletes to decrease concussion severity and duration. PMID:27005467

Driving with head-slaved camera system

NARCIS (Netherlands)

Oving, A.B.; Erp, J.B.F. van

2001-01-01

In a field experiment, we tested the effectiveness of a head-slaved camera system for driving an armoured vehicle under armour. This system consists of a helmet-mounted display (HMD), a headtracker, and a motion platform with two cameras. Subjects performed several driving tasks on paved and in

Psychological models for development of motorcycle helmet use among students in Vietnam

Science.gov (United States)

Kumphong, J.; Satiennam, T.; Satiennam, W.; Trinh, Tu Anh

2018-04-01

A helmet can reduce head accident severity. The aim of this research study was to study the intention for helmet use of students who ride motorcycles in Vietnam, by Structural Equation Modeling (SEM). Questionnaires developed by several traffic psychology modules, including the Theory of Planned Behaviour (TPB), Traffic Locus of Control (T-LOC), and Health Belief Model (HBM), were distributed to students at Ton Thang University and University of Architecture, Ho Chi Minh City. SEM was used to explain helmet use behaviour. The results indicate that TPB, T-LOC and HBM could explain the variance in helmet use behaviour. However, TPB can explain behaviour (helmet use intention) better than T-LOC and HBM. The outcome of this study is useful for the agencies responsible to improve motorcycle safety.

Talk to the virtual hands: self-animated avatars improve communication in head-mounted display virtual environments.

Directory of Open Access Journals (Sweden)

Trevor J Dodds

Full Text Available BACKGROUND: When we talk to one another face-to-face, body gestures accompany our speech. Motion tracking technology enables us to include body gestures in avatar-mediated communication, by mapping one's movements onto one's own 3D avatar in real time, so the avatar is self-animated. We conducted two experiments to investigate (a whether head-mounted display virtual reality is useful for researching the influence of body gestures in communication; and (b whether body gestures are used to help in communicating the meaning of a word. Participants worked in pairs and played a communication game, where one person had to describe the meanings of words to the other. PRINCIPAL FINDINGS: In experiment 1, participants used significantly more hand gestures and successfully described significantly more words when nonverbal communication was available to both participants (i.e. both describing and guessing avatars were self-animated, compared with both avatars in a static neutral pose. Participants 'passed' (gave up describing significantly more words when they were talking to a static avatar (no nonverbal feedback available. In experiment 2, participants' performance was significantly worse when they were talking to an avatar with a prerecorded listening animation, compared with an avatar animated by their partners' real movements. In both experiments participants used significantly more hand gestures when they played the game in the real world. CONCLUSIONS: Taken together, the studies show how (a virtual reality can be used to systematically study the influence of body gestures; (b it is important that nonverbal communication is bidirectional (real nonverbal feedback in addition to nonverbal communication from the describing participant; and (c there are differences in the amount of body gestures that participants use with and without the head-mounted display, and we discuss possible explanations for this and ideas for future investigation.

Methodologies for Blunt Trauma Assessment in Military Helmets

Science.gov (United States)

2010-09-13

Assessment; Monorail Drop Tower 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT UU 18. NUMBER OF PAGES 10 19a. NAME OF RESPONSIBLE...Laboratory Test Procedure for Motorcycle Helmets (TP-218-06) [8]. TP-218-06 specifies a guided monorail drop and provides requirements for how helmets...a hemispherical anvil. The monorail restricts movement to control the impact location, and acceleration is measured using a uniaxial accelerometer

Novel Method of Weighting Cumulative Helmet Impacts Improves Correlation with Brain White Matter Changes After One Football Season of Sub-concussive Head Blows.

Science.gov (United States)

Merchant-Borna, Kian; Asselin, Patrick; Narayan, Darren; Abar, Beau; Jones, Courtney M C; Bazarian, Jeffrey J

2016-12-01

One football season of sub-concussive head blows has been shown to be associated with subclinical white matter (WM) changes on diffusion tensor imaging (DTI). Prior research analyses of helmet-based impact metrics using mean and peak linear and rotational acceleration showed relatively weak correlations to these WM changes; however, these analyses failed to account for the emerging concept that neuronal vulnerability to successive hits is inversely related to the time between hits (TBH). To develop a novel method for quantifying the cumulative effects of sub-concussive head blows during a single season of collegiate football by weighting helmet-based impact measures for time between helmet impacts. We further aim to compare correlations to changes in DTI after one season of collegiate football using weighted cumulative helmet-based impact measures to correlations using non-weighted cumulative helmet-based impact measures and non-cumulative measures. We performed a secondary analysis of DTI and helmet impact data collected on ten Division III collegiate football players during the 2011 season. All subjects underwent diffusion MR imaging before the start of the football season and within 1 week of the end of the football season. Helmet impacts were recorded at each practice and game using helmet-mounted accelerometers, which computed five helmet-based impact measures for each hit: linear acceleration (LA), rotational acceleration (RA), Gadd Severity Index (GSI), Head Injury Criterion (HIC 15 ), and Head Impact Technology severity profile (HITsp). All helmet-based impact measures were analyzed using five methods of summary: peak and mean (non-cumulative measures), season sum-totals (cumulative unweighted measures), and season sum-totals weighted for time between hits (TBH), the interval of time from hit to post-season DTI assessment (TUA), and both TBH and TUA combined. Summarized helmet-based impact measures were correlated to statistically significant changes in

GPK helmets protecting from gas and dusts

Energy Technology Data Exchange (ETDEWEB)

Il' inskii, Eh.G.; Kogan, Yu.A.; Mazanenko, V.P.

1983-08-01

The GPK protective helmet with an integrated respirator system protecting a miner's respiratory system and eyes from gases and dusts is described. The system uses compressed air from the mine compressed air system. Air is supplied to the respirator by an elastic rubber pipe to 30 m long. The air cools the miner's head under the helmet and passes between a protective shield and the miner's face protecting eyes and the respiratory system. Air supply ranges from 100 to 150 l/min. The air supplied to the respirator is cleaned by a filter. The GPK system weighs 1.2 kg. The system has been tested under laboratory conditions and in two coal mines under operational conditions at longwall faces and during mine drivage. Tests showed that the GPK guarantees efficient cooling and protection from dust. Design of the GPK helmet with a respirator is shown in two schemes. Technical specifications of the system are given.

Modular liquid-cooled helmet liner for thermal comfort

Science.gov (United States)

Williams, B. A.; Shitzer, A.

1974-01-01

A modular liquid-cooled helmet liner made of eight form-fitting neoprene patches was constructed. The liner was integrated into the sweatband of an Army SPH-4 helicopter aircrew helmet. This assembly was tested on four subjects seated in a hot (47 C), humid (40%) environment. Results indicate a marked reduction in the rate of increase of physiological body functions. Rectal temperature, weight loss, heart rate, and strain indices are all reduced to approximately 50% of uncooled levels. The cooling liner removed from 10% to 30% of total metabolic heat produced. This study also demonstrated the technical feasilibity of using a cooling liner in conjunction with a standard hard helmet. Potential applications of the cooling liner in thermally stressful environments are numerous, notably for helicopter and other aircrews.

Binocular vision in a virtual world: visual deficits following the wearing of a head-mounted display.

Science.gov (United States)

Mon-Williams, M; Wann, J P; Rushton, S

1993-10-01

The short-term effects on binocular stability of wearing a conventional head-mounted display (HMD) to explore a virtual reality environment were examined. Twenty adult subjects (aged 19-29 years) wore a commercially available HMD for 10 min while cycling around a computer generated 3-D world. The twin screen presentations were set to suit the average interpupillary distance of our subject population, to mimic the conditions of public access virtual reality systems. Subjects were examined before and after exposure to the HMD and there were clear signs of induced binocular stress for a number of the subjects. The implications of introducing such HMDs into the workplace and entertainment environments are discussed.

A cross-sectional observational study of helmet use among motorcyclists in Wa, Ghana.

Science.gov (United States)

Akaateba, Millicent Awialie; Amoh-Gyimah, Richard; Yakubu, Ibrahim

2014-03-01

Motorcyclists' injuries and fatalities are a major public health concern in many developing countries including Ghana. This study therefore aimed to investigate the prevalence of helmet use among motorcyclists in Wa, Ghana. The method used involved a cross-sectional roadside observation at 12 randomly selected sites within and outside the CBD of Wa. A total of 14,467 motorcyclists made up of 11,360 riders and 3107 pillion riders were observed during the study period. Most observed riders (86.5%) and pillion riders (61.7%) were males. The overall prevalence of helmet use among the observed motorcyclists was 36.9% (95% CI: 36.1-37.7). Helmet use for riders was 45.8% (95% CI: 44.8-46.7) whilst that for pillion riders was 3.7% (95 CI: 3.0-4.4). Based on logistic regression analysis, higher helmet wearing rates were found to be significantly associated with female gender, weekdays, morning periods and at locations within the CBD. Riders at locations outside the CBD were about 7 times less likely to wear a helmet than riders within the CBD (48.9% compared to 42.3%; χ(2)(1)=49.526; plegislation that mandates the use of helmets by both riders and pillion riders on all roads in Ghana, helmet use is generally low in Wa. This suggests that all stakeholders in road safety should jointly intensify education on helmet use and pursue rigorous enforcement on all road types especially at locations outside the CBD to improve helmet use in Wa. Copyright © 2013 Elsevier Ltd. All rights reserved.

Injuries of the head from backface deformation of ballistic protective helmets under ballistic impact.

Science.gov (United States)

Rafaels, Karin A; Cutcliffe, Hattie C; Salzar, Robert S; Davis, Martin; Boggess, Brian; Bush, Bryan; Harris, Robert; Rountree, Mark Steve; Sanderson, Ellory; Campman, Steven; Koch, Spencer; Dale Bass, Cameron R

2015-01-01

Modern ballistic helmets defeat penetrating bullets by energy transfer from the projectile to the helmet, producing helmet deformation. This deformation may cause severe injuries without completely perforating the helmet, termed "behind armor blunt trauma" (BABT). As helmets become lighter, the likelihood of larger helmet backface deformation under ballistic impact increases. To characterize the potential for BABT, seven postmortem human head/neck specimens wearing a ballistic protective helmet were exposed to nonperforating impact, using a 9 mm, full metal jacket, 124 grain bullet with velocities of 400-460 m/s. An increasing trend of injury severity was observed, ranging from simple linear fractures to combinations of linear and depressed fractures. Overall, the ability to identify skull fractures resulting from BABT can be used in forensic investigations. Our results demonstrate a high risk of skull fracture due to BABT and necessitate the prevention of BABT as a design factor in future generations of protective gear. © 2014 American Academy of Forensic Sciences.

A review of the use of virtual reality head-mounted displays in education and training

DEFF Research Database (Denmark)

Jensen, Lasse; Konradsen, Flemming

2017-01-01

In the light of substantial improvements to the quality and availability of virtual reality (VR) hardware seen since 2013, this review seeks to update our knowledge about the use of head-mounted displays (HMDs) in education and training. Following a comprehensive search 21 documents reporting...... on experimental studies were identified, quality assessed, and analysed. The quality assessment shows that the study quality was below average according to the Medical Education Research Study Quality Instrument, especially for the studies that were designed as user evaluations of educational VR products......; and affective skills related to controlling your emotional response to stressful or difficult situations. Outside of these situations the HMDs had no advantage when compared to less immersive technologies or traditional instruction and in some cases even proved counterproductive because of widespread...

Helmets or not? Use science correctly.

Science.gov (United States)

Trégouët, Paul

2015-08-01

In a recent article, Hooper and Spicer make several arguments against legislation that would mandate the use of bicycle helmets. While they present reasonable objections to the utilitarian as well as the justice defence of such legislation, their review of the empirical evidence contains inaccuracies, omissions and a bias in the selection of empirical data. While there are legitimate reasons to argue against mandating helmet legislation, these arguments should still be based on clinically and scientifically sound evidence. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The influence of ski helmets on sound perception and sound localisation on the ski slope

Directory of Open Access Journals (Sweden)

Lana Ružić

2015-04-01

Full Text Available Objectives: The aim of the study was to investigate whether a ski helmet interferes with the sound localization and the time of sound perception in the frontal plane. Material and Methods: Twenty-three participants (age 30.7±10.2 were tested on the slope in 2 conditions, with and without wearing the ski helmet, by 6 different spatially distributed sound stimuli per each condition. Each of the subjects had to react when hearing the sound as soon as possible and to signalize the correct side of the sound arrival. Results: The results showed a significant difference in the ability to localize the specific ski sounds; 72.5±15.6% of correct answers without a helmet vs. 61.3±16.2% with a helmet (p < 0.01. However, the performance on this test did not depend on whether they were used to wearing a helmet (p = 0.89. In identifying the timing, at which the sound was firstly perceived, the results were also in favor of the subjects not wearing a helmet. The subjects reported hearing the ski sound clues at 73.4±5.56 m without a helmet vs. 60.29±6.34 m with a helmet (p < 0.001. In that case the results did depend on previously used helmets (p < 0.05, meaning that that regular usage of helmets might help to diminish the attenuation of the sound identification that occurs because of the helmets. Conclusions: Ski helmets might limit the ability of a skier to localize the direction of the sounds of danger and might interfere with the moment, in which the sound is firstly heard.

Achieving all-age helmet use compliance for snow sports: strategic use of education, legislation and enforcement.

Science.gov (United States)

Fenerty, Lynne; Heatley, Jennifer; Young, Julian; Thibault-Halman, Ginette; Kureshi, Nelofar; Bruce, Beth S; Walling, Simon; Clarke, David B

2016-06-01

Nova Scotia is the first jurisdiction in the world to mandate ski and snowboard helmet use for all ages at ski hills in the province. This study represents a longitudinal examination of the effects of social marketing, educational campaigns and the introduction of helmet legislation on all-age snow sport helmet use in Nova Scotia. A baseline observational study was conducted to establish the threshold of ski and snowboarding helmet use. Based on focus groups and interviews, a social marketing campaign was designed and implemented to address factors influencing helmet use. A prelegislation observational study assessed the effects of social marketing and educational promotion on helmet use. After all-age snow sport helmet legislation was enacted and enforced, a postlegislation observational study was conducted to determine helmet use prevalence. Baseline data revealed that 74% of skiers and snowboarders were using helmets, of which 80% were females and 70% were males. Helmet use was high in children (96%), but decreased with increasing age. Following educational and social marketing campaigns, overall helmet use increased to 90%. After helmet legislation was enacted, 100% compliance was observed at ski hills in Nova Scotia. Results from this study demonstrate that a multifaceted approach, including education, legislation and enforcement, was effective in achieving full helmet compliance among all ages of skiers and snowboarders. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Helmet-Induced Occipital Neuralgia in a Military Aviator.

Science.gov (United States)

Chalela, Julio A

2018-04-01

Headaches among military personnel are very common and headgear wear is a frequently identified culprit. Helmet wear may cause migrainous headaches, external compression headache, other primary cranial neuralgias, and occipital neuralgia. The clinical features and the response to treatment allow distinction between the different types of headaches. Headaches among aviators are particularly concerning as they may act as distractors while flying and the treatment options are often incompatible with flying status. A 24-yr-old door gunner presented with suboccipital pain associated with the wear of his helmet. He described the pain as a paroxysmal stabbing sensation coming in waves. The physical exam and history supported the diagnosis of primary occipital neuralgia. Systemic pharmacological options were discussed with the soldier, but rejected due to his need to remain in flying status. An occipital nerve block was performed with good clinical results, supporting the diagnosis of occipital neuralgia and allowing him to continue as mission qualified. Occipital neuralgia can be induced by helmet wear in military personnel. Occipital nerve block can be performed in the deployed setting, allowing the service member to remain mission capable and sparing him/her from systemic side effects.Chalela JA. Helmet-induced occipital neuralgia in a military aviator. Aerosp Med Hum Perform. 2018; 89(4):409-410.

Dynamic Response and Residual Helmet Liner Crush Using Cadaver Heads and Standard Headforms.

Science.gov (United States)

Bonin, S J; Luck, J F; Bass, C R; Gardiner, J C; Onar-Thomas, A; Asfour, S S; Siegmund, G P

2017-03-01

Biomechanical headforms are used for helmet certification testing and reconstructing helmeted head impacts; however, their biofidelity and direct applicability to human head and helmet responses remain unclear. Dynamic responses of cadaver heads and three headforms and residual foam liner deformations were compared during motorcycle helmet impacts. Instrumented, helmeted heads/headforms were dropped onto the forehead region against an instrumented flat anvil at 75, 150, and 195 J. Helmets were CT scanned to quantify maximum liner crush depth and crush volume. General linear models were used to quantify the effect of head type and impact energy on linear acceleration, head injury criterion (HIC), force, maximum liner crush depth, and liner crush volume and regression models were used to quantify the relationship between acceleration and both maximum crush depth and crush volume. The cadaver heads generated larger peak accelerations than all three headforms, larger HICs than the International Organization for Standardization (ISO), larger forces than the Hybrid III and ISO, larger maximum crush depth than the ISO, and larger crush volumes than the DOT. These significant differences between the cadaver heads and headforms need to be accounted for when attempting to estimate an impact exposure using a helmet's residual crush depth or volume.

[Prevalence of helmet use in children and adolescents in Germany and preventable bicycle-related head injuries].

Science.gov (United States)

Gutsche, J; Hintzpeter, B; Neuhauser, H; Schlaud, M

2011-08-01

Head injuries are the main cause of death in bicycle-related accidents among children and adolescents. According to a Cochrane Review, the risk of head injury (OR 0.31; 95% CI 0.26-0.37) or brain injury (OR 0.31; 95% CI 0.23-0.42) decreases by 69% if a helmet is worn. This study presents the prevalence of helmet use in cycling children and adolescents in Germany and the proportion of head injuries that could be prevented by wearing helmets. The potential effects of increased helmet wearing rates on the population attributable risk percentage for head injuries (PAR%) are demonstrated. The prevalence of helmet use in children aged 3-17 years was analysed using data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). The percentage of head injuries preventable by helmet use in this group is estimated by calculating PAR%. Prevalence rates of helmet use and odds ratios from a Cochrane Review about the effectiveness of bicycle helmets for the prevention of head injuries were used for analysis. The potential effect of increased helmet use is shown in 3 scenarios by means of differences of PAR% values in the most relevant age groups. The older the children, the less likely they are to wear a helmet: 89.5% (95% CI 88.0%-90.8%) of the 3- to 6-year-old children wear a helmet when cycling but only 11.0% (95% CI 9.3%-12.9%) of 14- to 17-year-old adolescents do. In the youngest group (3-6 years) 19% of bicycle-related head injuries are attributable to the non-use of helmets, but this proportion rises to 67% in the oldest group (14-17 years). The PAR% of head injuries associated with not wearing a helmet may be reduced by more than a third by increasing the helmet wearing rate to 67% (2 out of 3) among adolescents, and may be reduced to half if 75% of adolescents wore a helmet. Particularly older children and adolescents hardly use bicycle helmets, hence the rate of preventable head injury is high. Efforts towards increasing helmet use

Preventive Effects of Safety Helmets on Traumatic Brain Injury after Work-Related Falls

Directory of Open Access Journals (Sweden)

Sang Chul Kim

2016-10-01

Full Text Available Introduction: Work-related traumatic brain injury (TBI caused by falls is a catastrophic event that leads to disabilities and high socio-medical costs. This study aimed to measure the magnitude of the preventive effect of safety helmets on clinical outcomes and to compare the effect across different heights of fall. Methods: We collected a nationwide, prospective database of work-related injury patients who visited the 10 emergency departments between July 2010 and October 2012. All of the adult patients who experienced work-related fall injuries were eligible, excluding cases with unknown safety helmet use and height of fall. Primary and secondary endpoints were intracranial injury and in-hospital mortality. We calculated adjusted odds ratios (AORs of safety helmet use and height of fall for study outcomes, and adjusted for any potential confounders. Results: A total of 1298 patients who suffered from work-related fall injuries were enrolled. The industrial or construction area was the most common place of fall injury occurrence, and 45.0% were wearing safety helmets at the time of fall injuries. The safety helmet group was less likely to have intracranial injury comparing with the no safety helmet group (the adjusted odds ratios (ORs (95% confidence interval (CI: 0.42 (0.24–0.73, however, there was no statistical difference of in-hospital mortality between two groups (the adjusted ORs (95% CI: 0.83 (0.34–2.03. In the interaction analysis, preventive effects of safety helmet on intracranial injury were significant within 4 m height of fall. Conclusions: A safety helmet is associated with prevention of intracranial injury resulting from work-related fall and the effect is preserved within 4 m height of fall. Therefore, wearing a safety helmet can be an intervention for protecting fall-related intracranial injury in the workplace.

A Thermal Test System for Helmet Cooling Studies

Directory of Open Access Journals (Sweden)

Shaun Fitzgerald

2018-02-01

Full Text Available One of the primary causes of discomfort to both irregular and elite cyclists is heat entrapment by a helmet resulting in overheating and excessive sweating of the head. To accurately assess the cooling effectiveness of bicycle helmets, a heated plastic thermal headform has been developed. The construction consists of a 3D-printed headform of low thermal conductivity with an internal layer of high thermal mass that is heated to a constant uniform temperature by an electrical heating element. Testing is conducted in a wind tunnel where the heater power remains constant and the resulting surface temperature distribution is directly measured by 36 K-type thermocouples embedded within the surface of the head in conjunction with a thermal imaging camera. Using this new test system, four bicycle helmets were studied in order to measure their cooling abilities and to identify ‘hot spots’ where cooling performance is poor.

Evaluation of a promotional strategy to increase bicycle helmet use by children.

Science.gov (United States)

Parkin, P C; Spence, L J; Hu, X; Kranz, K E; Shortt, L G; Wesson, D E

1993-04-01

Bicycle-related head injuries are an important cause of death and disability, despite the availability of helmets. The objective of this study was to evaluate the effectiveness of a school-based bicycle helmet promotion program in increasing helmet use by children while controlling for secular trends. Two high-income and two low-income schools in an urban Canadian community were selected to receive a bicycle helmet promotion intervention, with the remaining 18 schools serving as controls. Approximately 1800 observations of bicycling children were made at randomly selected observational sites 2 to 5 months after the intervention to assess changes in behavior. Helmet use at all observation sites tripled from 3.4% (1990, preintervention) to 16% (1991, postintervention). In the high-income intervention area, observed helmet use rose dramatically from 4% to 36% in contrast to the more modest increase in the high-income control area from 4% to 15%. In the low-income intervention area, there was a modest increase from 1% to 7%, but it did not differ from the increase in the low-income control area from 3% to 13%. The program was highly successful in children of high-income families but not in children of low-income families. Developing strategies for low-income families remains a priority.

Transparent 3D display for augmented reality

Science.gov (United States)

Lee, Byoungho; Hong, Jisoo

2012-11-01

Two types of transparent three-dimensional display systems applicable for the augmented reality are demonstrated. One of them is a head-mounted-display-type implementation which utilizes the principle of the system adopting the concave floating lens to the virtual mode integral imaging. Such configuration has an advantage in that the threedimensional image can be displayed at sufficiently far distance resolving the accommodation conflict with the real world scene. Incorporating the convex half mirror, which shows a partial transparency, instead of the concave floating lens, makes it possible to implement the transparent three-dimensional display system. The other type is the projection-type implementation, which is more appropriate for the general use than the head-mounted-display-type implementation. Its imaging principle is based on the well-known reflection-type integral imaging. We realize the feature of transparent display by imposing the partial transparency to the array of concave mirror which is used for the screen of reflection-type integral imaging. Two types of configurations, relying on incoherent and coherent light sources, are both possible. For the incoherent configuration, we introduce the concave half mirror array, whereas the coherent one adopts the holographic optical element which replicates the functionality of the lenslet array. Though the projection-type implementation is beneficial than the head-mounted-display in principle, the present status of the technical advance of the spatial light modulator still does not provide the satisfactory visual quality of the displayed three-dimensional image. Hence we expect that the head-mounted-display-type and projection-type implementations will come up in the market in sequence.

Does listening to music with an audio ski helmet impair reaction time to peripheral stimuli?

Science.gov (United States)

Ruedl, G; Pocecco, E; Wolf, M; Schöpf, S; Burtscher, M; Kopp, M

2012-12-01

With the recent worldwide increase in ski helmet use, new market trends are developing, including audio helmets for listening to music while skiing or snowboarding. The aim of this study was to evaluate whether listening to music with an audio ski helmet impairs reaction time to peripheral stimuli. A within-subjects design study using the Compensatory-Tracking-Test was performed on 65 subjects (36 males and 29 females) who had a mean age of 23.3 ± 3.9 years. Using repeated measures analysis of variance, we found significant differences in reaction times between the 4 test conditions (p=0.039). The lowest mean reaction time (± SE) was measured for helmet use while listening to music (507.9 ± 13.2 ms), which was not different from helmet use alone (514.6 ± 12.5 ms) (p=0.528). However, compared to helmet use while listening to music, reaction time was significantly longer for helmet and ski goggles used together (535.8 ± 14.2 ms, p=0.005), with a similar trend for helmet and ski goggles used together while listening to music (526.9 ± 13.8 ms) (p=0.094). In conclusion, listening to music with an audio ski helmet did not increase mean reaction time to peripheral stimuli in a laboratory setting. © Georg Thieme Verlag KG Stuttgart · New York.

The evaluation of speed skating helmet performance through peak linear and rotational accelerations.

Science.gov (United States)

Karton, Clara; Rousseau, Philippe; Vassilyadi, Michael; Hoshizaki, Thomas Blaine

2014-01-01

Like many sports involving high speeds and body contact, head injuries are a concern for short track speed skating athletes and coaches. While the mandatory use of helmets has managed to nearly eliminate catastrophic head injuries such as skull fractures and cerebral haemorrhages, they may not be as effective at reducing the risk of a concussion. The purpose of this study was to evaluate the performance characteristics of speed skating helmets with respect to managing peak linear and peak rotational acceleration, and to compare their performance against other types of helmets commonly worn within the speed skating sport. Commercially available speed skating, bicycle and ice hockey helmets were evaluated using a three-impact condition test protocol at an impact velocity of 4 m/s. Two speed skating helmet models yielded mean peak linear accelerations at a low-estimated probability range for sustaining a concussion for all three impact conditions. Conversely, the resulting mean peak rotational acceleration values were all found close to the high end of a probability range for sustaining a concussion. A similar tendency was observed for the bicycle and ice hockey helmets under the same impact conditions. Speed skating helmets may not be as effective at managing rotational acceleration and therefore may not successfully protect the user against risks associated with concussion injuries.

Face mask removal is safer than helmet removal for emergent airway access in American football.

Science.gov (United States)

Swartz, Erik E; Mihalik, Jason P; Beltz, Nora M; Day, Molly A; Decoster, Laura C

2014-06-01

In cases of possible cervical spine injury, medical professionals must be prepared to achieve rapid airway access while concurrently restricting cervical spine motion. Face mask removal (FMR), rather than helmet removal (HR), is recommended to achieve this. However, no studies have been reported that compare FMR directly with HR. The purpose of this study was to compare motion, time, and perceived difficulty in two commonly used American football helmets between FMR and HR techniques, and when helmet air bladders were deflated before HR compared with inflated scenarios. The study incorporated a repeated measures design and was performed in a controlled laboratory setting. Participants included 22 certified athletic trainers (15 men and seven women; mean age, 33.9±10.5 years; mean experience, 11.4±10.0 years; mean height, 172±9.4 cm; mean mass, 76.7±14.9 kg). All participants were free from upper extremity or central nervous system pathology for 6 months and provided informed consent. Dependent variables included head excursion in degrees (computed by subtracting the minimum position from the maximum position) in each of the three planes (sagittal, frontal, transverse), time to complete the required task, and ratings of perceived exertion. To address our study purposes, we used two-by-two repeated-measures analysis of variance (removal technique×helmet type, helmet type×deflation status) for each dependent variable. Independent variables consisted of removal technique (FMR and HR), helmet type (Riddell Revolution IQ [RIQ] and VSR4), and helmet deflation status (deflated [D], inflated, [I]). After familiarization, participants conducted two successful trials for each of six conditions in random order (RIQ-FMR, VSR4-FMR, RIQ-HR-D, VSR4-HR-D, RIQ-HR-I, and VSR4-HR-I). Face masks, helmets, and shoulder pads were removed from a live model wearing a properly fitted helmet and shoulder pads. The participant and an investigator stabilized the model's head. A six

Noise exposure is increased with neonatal helmet CPAP in comparison with conventional nasal CPAP.

Science.gov (United States)

Trevisanuto, D; Camiletti, L; Doglioni, N; Cavallin, F; Udilano, A; Zanardo, V

2011-01-01

in adults, noninvasive ventilation via a helmet is associated with significantly greater noise than nasal and facial masks. We hypothesized that noise exposure could be increased with neonatal helmet continuous positive airway pressure (CPAP) in comparison with conventional nasal CPAP (nCPAP). Our primary objective was to compare the noise intensity produced by a neonatal helmet CPAP and a conventional nCPAP system. Furthermore, we aimed to evaluate the effect of the gas flow rate and the presence of the humidifier and the filter on noise levels during neonatal helmet CPAP treatment. in this bench study, noise intensity was measured in the following settings: helmet CPAP, nCPAP, incubator and the neonatal intensive care unit. In helmet CPAP, noise measurements were performed at different gas flow rates (8, 10 and 12 l/min), while in nCPAP, the flow rate was 8 l/min. For both CPAP systems, the level of pressure was maintained constant at 5 cmH(2) O. during neonatal helmet CPAP, the median (interquartile range) noise levels were significantly higher than those during nCPAP: 70.0 dB (69.9-70.4) vs. 62.7 dB (62.5-63.0); PCPAP, the noise intensities changed with increasing flow rate and with the presence of a humidifier or a filter. noise intensities generated by the neonatal helmet CPAP were significantly higher than those registered while using a conventional nCPAP system. In the helmet, the noise intensity depends on the gas flow rate, and the presence of a humidifier and a filter in the system. 2010 The Acta Anaesthesiologica Scandinavica Foundation.

Combat Helmet-Headform Coupling Characterized from Blunt Impact Events

Science.gov (United States)

2011-11-01

Testing was completed on a monorail drop tower to analyze the effect of helmet/headform coupling on the blunt impact behavior of ACH helmets using FMVSS...designates its own methods and test equipment: a drop tower ( monorail or twin- wire), headform (DOT, ISO, NOCSAE), headform CG accelerometer (single or...the more anthropomorphic International Standard Organization (ISO) half headform. Testing was completed on a monorail drop tower to analyze the effect

Head position in the MEG helmet affects the sensitivity to anterior sources.

Science.gov (United States)

Marinkovic, K; Cox, B; Reid, K; Halgren, E

2004-11-30

Current MEG instruments derive the whole-head coverage by utilizing a helmet-shaped opening at the bottom of the dewar. These helmets, however, are quite a bit larger than most people's heads so subjects commonly lean against the back wall of the helmet in order to maintain a steady position. In such cases the anterior brain sources may be too distant to be picked up by the sensors reliably. Potential "invisibility" of the frontal and anterior temporal sources may be particularly troublesome for the studies of cognition and language, as they are subserved significantly by these areas. We examined the sensitivity of the distributed anatomically-constrained MEG (aMEG) approach to the head position ("front" vs. "back") secured within a helmet with custom-tailored bite-bars during a lexical decision task. The anterior head position indeed resulted in much greater sensitivity to language-related activity in frontal and anterior temporal locations. These results emphasize the need to adjust the head position in the helmet in order to maximize the "visibility" of the sources in the anterior brain regions in cognitive and language tasks.

3D display system using monocular multiview displays

Science.gov (United States)

Sakamoto, Kunio; Saruta, Kazuki; Takeda, Kazutoki

2002-05-01

A 3D head mounted display (HMD) system is useful for constructing a virtual space. The authors have researched the virtual-reality systems connected with computer networks for real-time remote control and developed a low-priced real-time 3D display for building these systems. We developed a 3D HMD system using monocular multi-view displays. The 3D displaying technique of this monocular multi-view display is based on the concept of the super multi-view proposed by Kajiki at TAO (Telecommunications Advancement Organization of Japan) in 1996. Our 3D HMD has two monocular multi-view displays (used as a visual display unit) in order to display a picture to the left eye and the right eye. The left and right images are a pair of stereoscopic images for the left and right eyes, then stereoscopic 3D images are observed.

Clinical review: Helmet and non-invasive mechanical ventilation in critically ill patients.

Science.gov (United States)

Esquinas Rodriguez, Antonio M; Papadakos, Peter J; Carron, Michele; Cosentini, Roberto; Chiumello, Davide

2013-04-25

Non-invasive mechanical ventilation (NIV) has proved to be an excellent technique in selected critically ill patients with different forms of acute respiratory failure. However, NIV can fail on account of the severity of the disease and technical problems, particularly at the interface. The helmet could be an alternative interface compared to face mask to improve NIV success. We performed a clinical review to investigate the main physiological and clinical studies assessing the efficacy and related issues of NIV delivered with a helmet. A computerized search strategy of MEDLINE/PubMed (January 2000 to May 2012) and EMBASE (January 2000 to May 2012) was conducted limiting the search to retrospective, prospective, nonrandomized and randomized trials. We analyzed 152 studies from which 33 were selected, 12 physiological and 21 clinical (879 patients). The physiological studies showed that NIV with helmet could predispose to CO₂ rebreathing and increase the patients' ventilator asynchrony. The main indications for NIV were acute cardiogenic pulmonary edema, hypoxemic acute respiratory failure (community-acquired pneumonia, postoperative and immunocompromised patients) and hypercapnic acute respiratory failure. In 9 of the 21 studies the helmet was compared to a face mask during either continous positive airway pressure or pressure support ventilation. In eight studies oxygenation was similar in the two groups, while the intubation rate was similar in four and lower in three studies for the helmet group compared to face mask group. The outcome was similar in six studies. The tolerance was better with the helmet in six of the studies. Although these data are limited, NIV delivered by helmet could be a safe alternative to the face mask in patients with acute respiratory failure.

A Discussion of the Issue of Football Helmet Removal in Suspected Cervical Spine Injuries

Science.gov (United States)

Segan, Ross D.; Cassidy, Christine; Bentkowski, Jamie

1993-01-01

In some areas, it is a commonly accepted emergency medical technician protocol to remove a helmet during the initial management of suspected cervical spine injures. After a comprehensive survey of relevant literature, four primary reasons why Emergency Medical Services professionals would desire to remove a helmet emerge. Sources suggest that the presence of a helmet might: 1) interfere with immobilization of the athlete; 2) interfere with the ability to visualize injuries; 3) cause hyperflexion of the cervical spine; and 4) prevent proper airway management during a cardiorespiratory emergency. Many available protocols are designed for the removal of closed chamber motorcycle helmets that do not have removable face masks. There are a great number of differing viewpoints regarding this issue. The varying viewpoints are results of the failure of many emergency medical technician management protocols to address the unique situation presented by a football helmet. We: 1) demonstrate that football helmet removal is potentially dangerous and unnecessary, 2) suggest that cardiorespiratory emergencies can be effectively managed without removing the helmet, and 3) provide sports medicine professional with information that may be used to establish a joint Emergency Medical Services/Sports Medicine emergency action plan. ImagesFig. 1.Fig 2.Fig 3.Fig 4.Fig 5.Fig 6. PMID:16558244

40° image intensifier tubes in an integrated helmet system

Science.gov (United States)

Schreyer, Herbert; Boehm, Hans-Dieter V.; Svedevall, B.

1993-12-01

EUROCOPTER has been under contract to the French and German ministries of defence for five years to develop the TIGER, a second generation anti-tank helicopter. A piloting thermal imager has been installed on a steerable platform in the helicopter nose in order to achieve the possibility of flying round the clock. In addition to this sensor, which is sensitive at a wavelength of 10 micrometers , the German side has proposed using an Integrated Helmet System in the PAH 2. This helmet, manufactured by GEC-Marconi Avionics, incorporates two cathode ray tubes (CRT) and two image intensifier tubes which allow the pilot to use an additional sensor in the visible and near infrared spectrum. The electronic part will be built by Teldix. EUROCOPTER DEUTSCHLAND has received the first demonstrator of this helmet for testing in the EUROCOPTER Visionics Laboratory. Later, the C-prototype will be integrated into a BK 117 helicopter (AVT Avionik Versuchstrager). This new helmet has a field of view of 40 degree(s), and exit pupil of 15 mm and improved possibilities of adjusting the optical part. Laboratory tests have been carried out to test important parameters like optical resolution under low light level conditions, field of view, eye relief or exit pupil. The CRT channels have been tested for resolution, distortion, vignetting and homogeneity. The requirements and the properties of the helmet, test procedures and the results of these tests are presented in the paper.

Prevalence and determinants of non-standard motorcycle safety helmets amongst food delivery workers in Selangor and Kuala Lumpur.

Science.gov (United States)

Kulanthayan, S; See, Lai Git; Kaviyarasu, Y; Nor Afiah, M Z

2012-05-01

Almost half of the global traffic crashes involve vulnerable groups such as pedestrian, cyclists and two-wheeler users. The main objective of this study was to determine the factors that influence standard of the safety helmets used amongst food delivery workers by presence of Standard and Industrial Research Institute of Malaysia (SIRIM) certification label. A cross sectional study was conducted amongst 150 food delivery workers from fast food outlets in the vicinity of Selangor and Kuala Lumpur. During observation, safety helmets were classified as standard safety helmet in the presence of SIRIM label and non-standard in the absence of the label. They were approached for questionnaire participation once consent was obtained and were requested to exchange their safety helmet voluntarily with a new one after the interview. Data analysis was carried out using SPSS. Chi square and logistic regression analysis was applied to determine the significance and odds ratio of the variables studied, respectively (penetration test, age, education level, knowledge, crash history, types of safety helmet, marital status and years of riding experience) against the presence of SIRIM label. The response rate for this study was 85.2%. The prevalence of non-standard helmets use amongst fast food delivery workers was 55.3%. Safety helmets that failed the penetration test had higher odds of being non-standard helmets compared with safety helmets passing the test. Types of safety helmet indicated half-shell safety helmets had higher odds to be non-standard safety helmets compared to full-shell safety helmets. Riders with more years of riding experience were in high odds of wearing non-standard safety helmets compared to riders with less riding experience. Non-standard (non-SIRIM approved) helmets were more likely to be half-shell helmets, were more likely to fail the standards penetration test, and were more likely to be worn by older, more experienced riders. The implications of these

Evaluation of stereoscopic video cameras synchronized with the movement of an operator's head on the teleoperation of the actual backhoe shovel

Science.gov (United States)

Minamoto, Masahiko; Matsunaga, Katsuya

1999-05-01

Operator performance while using a remote controlled backhoe shovel is described for three different stereoscopic viewing conditions: direct view, fixed stereoscopic cameras connected to a helmet mounted display (HMD), and rotating stereo camera connected and slaved to the head orientation of a free moving stereo HMD. Results showed that the head- slaved system provided the best performance.

BICYCLE HELMET DESIGN AND THE VIRTUAL VALIDATION OF THE IMPACT, AERODYNAMICS AND PRODUCTION PROCESS

Directory of Open Access Journals (Sweden)

Bojan Boshevski

2017-12-01

Full Text Available This paper presents the development process of a bicycle helmet through individual research, creation, presentation and analysis of the results of the most important product development stages. The quality of the development and manufacturing process of the protective equipment for extreme sports is an imperative for a successful product and its flawless function. The design of the bicycle helmet is made following the rules of the design in order to create a well-founded and functional product. After creating design sketches, a virtual prototype was developed in "SolidWorks" using the required ergonomic dimensions. 3D printed model of the human head with adapted ergonomic dimensions and the designed bicycle helmet was developed in order to verify the applied ergonomic measures. The virtual model will be used as an input in the finite element analysis of the helmet impact test based on the EN1078 standard and the aerodynamic simulations executed in "SolidWorks Simulation and Flow Simulation", for verification of the impact and aerodynamic properties. Virtual testing of aerodynamic features and the ability of the bicycle helmet to allow ventilation of the user's head indicate that the helmet performs its function in the desired way. Also, the virtual prototype will be used for the production process simulation in "SolidWorks Plastics" in order to analyze the production of the bicycle helmet. The polycarbonate helmet outer shell is subject to a number of simulations for the sake of analyzing the production process in order to obtain the desired characteristics of the polycarbonate outer shell and to avoid the disadvantages that occur in the manufacturing process. The main goal of this paper is to develop a safety bicycle helmet with improved ergonomic, validation of impact, aerodynamic characteristics and production process in order to produce a high quality product for mass use.

Auditory and visual reaction time and peripheral field of vision in helmet users

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Abbupillai Adhilakshmi

2016-12-01

Full Text Available Background: The incidence of fatal accidents are more in two wheeler drivers compared to four wheeler drivers. Head injury is of serious concern when recovery and prognosis of the patients are warranted, helmets are being used for safety purposes by moped, scooters and motorcycle drivers. Although, helmets are designed with cushioning effect to prevent head injuries but there are evidences of increase risk of neck injuries and reduced peripheral vision and hearing in helmet users. A complete full coverage helmets provide about less than 3 percent restrictions in horizontal peripheral visual field compared to rider without helmet. The standard company patented ergonomically designed helmets which does not affect the peripheral vision neither auditory reaction time. Objective: This pilot study aimed to evaluate the peripheral field of vision and auditory and visual reaction time in a hypertensive, diabetic and healthy male and female in order to have a better insight of protective characteristics of helmet in health and disease. Method: This pilot study carried out on age matched male of one healthy, one hypertensive and one diabetic and female subject of one healthy, one hypertensive and one diabetics. The field of vision was assessed by Lister’s perimeter whereas auditory and visual reaction time was recorded with response analyser. Result : Gender difference was not noted in peripheral field of vision but mild difference was found in auditory reaction time for high frequency and visual reaction time for both red and green colour in healthy control. But lateral and downward peripheral visual field was found reduced whereas auditory and visual reaction time was found increased in both hypertensive and diabetic subject in both sexes. Conclusion: Peripheral vision, auditory reaction time and visual reaction time in hypertensive and diabetics may lead to vulnerable accident. Helmet use has proven to reduce extent of injury in motorcyclist and

Do helmets worn for hurling fail to protect the ear? Identification of an emerging injury pattern.

LENUS (Irish Health Repository)

Martin-Smith, James D

2012-12-01

Hurling is an Irish national game of stick and ball known for its ferocity, played by 190 000 players. Facial injuries were common but have been significantly reduced by legislation enforcing compulsory helmet wearing. Current standard helmets worn by hurlers do not offer protection to the external ear. Here we describe an emerging pattern of ear injuries and demonstrate the risk of external ear injuries in hurlers complying with current helmet safety standards. A 6-month retrospective analysis was carried out of patients attending Cork University Hospital (CUH) with ear lacerations sustained while hurling. Patient notes were reviewed and helmet manufacturers were interviewed. Seven patients were identified, all of whom sustained complex through ear lacerations while wearing helmets complying with current safety standards. Current helmet design fails to protect the external ear placing it at an increased risk of injury, a potential solution is to include ear protection in the helmet design.

Bikes, helmets, and public health: decision-making when goods collide.

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Bateman-House, Alison

2014-06-01

How ought public officials address policy choices that entail trade-offs between desirable public health goods? Increasing cycling improves public health both by promoting physical activity and by decreasing vehicle use, thus reducing vehicular emissions. Proponents of bicycle helmets argue that, used properly, they protect individual cyclists; however, there is concern that mandating helmet use may result in a decrease in cycling. In 2012, New York City Mayor Michael Bloomberg opposed a bicycle helmet mandate, concerned that it would have a negative impact on the city's cycling rate, which he had sought to increase. The mayor did not explain his rationale, leaving constituents unsure why he opposed the proposal. This case study underscores the challenge of creating public policy in the context of competing public health goods.

The Theory of Planned Behavior and Helmet Use among College Students

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Ross, Lisa Thomson; Ross, Thomas P.; Farber, Sarah; Davidson, Caroline; Trevino, Meredith; Hawkins, Ashley

2011-01-01

Objectives: To assess undergraduate helmet use attitudes and behaviors in accordance with the theory of planned behavior (TPB). We predicted helmet wearers and nonwearers would differ on our subscales. Methods: Participants (N = 414, 69% female, 84% white) completed a survey. Results: Principal component analysis and reliability analysis guided…

Offsetting or Enhancing Behavior: An Empirical Analysis of Motorcycle Helmet Safety Legislation.

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Lee, Jonathan M

2015-10-01

This study uses state-level panel data from a 33-year period to test the hypotheses of offsetting and enhancing behavior with regards to motorcycle helmet legislation. Results presented in this article find no evidence of offsetting behavior and are consistent with the presence of enhancing behavior. State motorcycle helmet laws are estimated to reduce motorcycle crashes by 18.4% to 31.9%. In the absence of any behavioral adaptations among motorcyclists mandatory helmet laws are not expected to have any significant impact on motorcycle crash rates. The estimated motorcycle crash reductions do not appear to be driven by omitted variable bias or nonclassical measurement error in reported crashes. Overall, the results strongly suggest that mandatory helmet laws yield significant changes in motorcycle mobility in the form of reduced risk taking and/or decreased utilization. © 2015 Society for Risk Analysis.

Comparative Outcomes of Traumatic Brain Injury from Biking Accidents With or Without Helmet Use.

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Dagher, Jehane H; Costa, Camille; Lamoureux, Julie; de Guise, Elaine; Feyz, Mitra

2016-01-01

To determine if health outcomes and demographics differ according to helmet status between persons with cycling-related traumatic brain injuries (TBI). This is a retrospective study of 128 patients admitted to the Montreal General Hospital following a TBI that occurred while cycling from 2007-2011. Information was collected from the Quebec trauma registry and the coroner's office in cases of death from cycling accidents. The independent variables collected were socio-demographic, helmet status, clinical and neurological patient information. The dependent variables evaluated were length of stay (LOS), extended Glasgow outcome scale (GOS-E), injury severity scale (ISS), discharge destination and death. 25% of cyclists wore a helmet. The helmet group was older, more likely to be university educated, married and retired. Unemployment, longer intensive care unit (ICU) stay, severe intracranial bleeding and neurosurgical interventions were more common in the no helmet group. There was no significant association between the severity of the TBI, ISS scores, GOS-E or death and helmet wearing. The median age of the subjects who died was higher than those who survived. Cyclists without helmets were younger, less educated, single and unemployed. They had more severe TBIs on imaging, longer LOS in ICU and more neurosurgical interventions. Elderly cyclists admitted to the hospital appear to be at higher risk of dying in the event of a TBI.

Injuries and helmet use related to non-motorized wheeled activities among pediatric patients.

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Lindsay, H; Brussoni, M

2014-07-01

Patients presenting to emergency departments (ED) for injuries resulting from recreational activities represent a unique source of information on important directions for injury prevention efforts. We describe the epidemiology of non-motorized wheeled activity-related injury in pediatric patients presenting to Canadian EDs as well as patients' helmet use. Data for the years 2004 to 2009 were abstracted from the Canadian Hospitals Injury Reporting and Prevention Program (CHIRPP), a national ED injury surveillance program in fifteen hospitals. Most of the 28 618 children aged 1 to 16 years injured during non-motorized wheeled activities were injured while cycling, followed by skateboarding. Most injuries occurred among boys. Children injured on scooters tended to be younger whereas skateboarders were the oldest. On average, the number of all injuries decreased by 6% over the time period. Falls were the most common mechanism of injury; 8.3% of patients had head injuries, which were seen more often among cyclists than other wheeled-activity users. Helmet use was greatest among cyclists (62.2%) and lowest among skateboarders (32.9%). Injured patients presenting to EDs in jurisdictions with legislation mandating helmet use had 2.12 greater odds of helmet use and 0.86 lesser odds of head injury compared with those presenting in jurisdictions without helmet laws. These results provide further evidence that legislation mandating helmet use may be an effective way of reducing injury among all wheeled-activity users. The small number of patients who presented with helmet use and protective gear (59.4% overall) suggests that this remains an area for intervention.

Enhanced/synthetic vision and head-worn display technologies for terminal maneuvering area NextGen operations

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Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Williams, Steven P.; Bailey, Randall E.; Shelton, Kevin J.; Norman, R. Mike

2011-06-01

NASA is researching innovative technologies for the Next Generation Air Transportation System (NextGen) to provide a "Better-Than-Visual" (BTV) capability as adjunct to "Equivalent Visual Operations" (EVO); that is, airport throughputs equivalent to that normally achieved during Visual Flight Rules (VFR) operations rates with equivalent and better safety in all weather and visibility conditions including Instrument Meteorological Conditions (IMC). These new technologies build on proven flight deck systems and leverage synthetic and enhanced vision systems. Two piloted simulation studies were conducted to access the use of a Head-Worn Display (HWD) with head tracking for synthetic and enhanced vision systems concepts. The first experiment evaluated the use a HWD for equivalent visual operations to San Francisco International Airport (airport identifier: KSFO) compared to a visual concept and a head-down display concept. A second experiment evaluated symbology variations under different visibility conditions using a HWD during taxi operations at Chicago O'Hare airport (airport identifier: KORD). Two experiments were conducted, one in a simulated San Francisco airport (KSFO) approach operation and the other, in simulated Chicago O'Hare surface operations, evaluating enhanced/synthetic vision and head-worn display technologies for NextGen operations. While flying a closely-spaced parallel approach to KSFO, pilots rated the HWD, under low-visibility conditions, equivalent to the out-the-window condition, under unlimited visibility, in terms of situational awareness (SA) and mental workload compared to a head-down enhanced vision system. There were no differences between the 3 display concepts in terms of traffic spacing and distance and the pilot decision-making to land or go-around. For the KORD experiment, the visibility condition was not a factor in pilot's rating of clutter effects from symbology. Several concepts for enhanced implementations of an unlimited field

Rates of motorcycle helmet use and reasons for non-use among adults and children in Luang Prabang, Lao People's Democratic Republic.

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Fong, Michelle C; Measelle, Jeffrey R; Dwyer, Jessica L; Taylor, Yvonne K; Mobasser, Arian; Strong, Theresa M; Werner, Susanne; Ouansavanh, Siamphone; Mounmingkham, Amphone; Kasuavang, Mai; Sittiphone, Dalika; Phoumesy, Khamhak; Sysaythong, Keo; Khantysavath, Khauphan; Bounnaphone, Somchit; Vilaysom, Amphone; Touvachao, Sengchanh; Mounmeuangxam, Siviengxam; Souralay, Somchittana; Lianosay, Baoher; Lia, Thongher; Spector, Jonathan M

2015-09-28

Motorcycles make up 81 % of the total vehicle population and 74 % of road traffic deaths in Lao PDR. Helmets reduce the risk and severity of injuries resulting from motorcycle accidents by 72 %. Although Lao law mandates motorcycle helmet use among drivers and passengers, the prevalence of helmet use in Luang Prabang, Lao PDR is unknown. This project aimed to measure the prevalence of motorcycle helmet use among riders (i.e., drivers and passengers) in Luang Prabang. An observational survey in Luang Prabang was conducted in February 2015 to measure the prevalence of motorcycle helmet use among drivers and passengers. Additionally, non-helmet wearing riders were surveyed to identify the reasons for helmet non-use. Of 1632 motorcycle riders observed, only 16.2 % wore helmets. Approximately 29 % of adults wore helmets while less than 1 % of all children wore helmets. When surveyed about attitudes towards helmet use, the majority of adult drivers indicated that they did not like how adult helmets feel or made them look. Additionally, almost half of motorcyclists who did not own child helmets reported that their child was too young to wear a helmet. Our finding that children wear helmets at significantly lower rates compared to adults is consistent with findings from neighboring countries in Southeast Asia. Results of this study have implications for public health campaigns targeting helmet use, especially among children.

Factors Influencing Helmet Use, Head Injury, and Hospitalization Among Children Involved in Skateboarding and Snowboarding Accidents.

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Sadeghian, Homa; Nguyen, Brian; Huynh, Nhan; Rouch, Joshua; Lee, Steven L; Bazargan-Hejazi, Shahrzad

2017-01-01

Up to 75% of skateboarders and snowboarders admitted to the hospital sustain head injuries. It is unclear why not all children and teenagers wear helmets while snowboarding and skateboarding given the protection they afford. To report on the prevalence of, and factors associated with, skateboarding and snowboarding in injured children and to explore factors that influence helmet use, head injury, and hospitalization in this sample. A cross-sectional study of skateboard- and snowboard-associated injuries from 2003 to 2012 among individuals younger than age 18 years using National Electronic Injury Surveillance System (NEISS) data from approximately 100 hospitals. Helmet use, head injury, and hospitalization. Of 1742 patients in the study, 852 (48.9%) and 890 (51.1%) were skateboarders and snowboarders, respectively. Overall, 907 (52.1%) did not use helmets, and 704 (40.4%) sustained head injuries. Multiple logistic regression analysis showed that age, race/ethnicity, location of boarding, and engaging in skateboarding influenced helmet use. Sex, race/ethnicity, helmet use, and skateboarding predicted head injury. Age, sex, skateboarding, and head injury predicted hospital admission. Statistically significant differences exist in helmet use, head injury, and hospitalization rates between skateboarders and snowboarders. Our findings suggest that injury prevention and outreach programs are needed to increase helmet use and reduce the risk of head injury and hospitalization in skateboarders and other at-risk groups. Further studies are needed to clarify the association between race/ethnicity and helmet use among skateboarders and snowboarders.

Maintaining neutral sagittal cervical alignment after football helmet removal during emergency spine injury management.

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Decoster, Laura C; Burns, Matthew F; Swartz, Erik E; Murthi, Dinakar S; Hernandez, Adam E; Vailas, James C; Isham, Linda L

2012-04-15

Descriptive laboratory study. To determine whether the placement of padding beneath the occiput after helmet removal is an effective intervention to maintain neutral sagittal cervical spine alignment in a position comparable with the helmeted condition. Current on-field recommendations for managing football athletes with suspected cervical spine injuries call for face mask removal, rather than helmet removal, because the combination of helmet and shoulder pads has been shown to maintain neutral cervical alignment. Therefore, in cases when helmet removal is required, recommendations also call for shoulder pad removal. Because removal of equipment causes motion, any technique that postpones the need to remove the shoulder pads would reduce prehospital motion. Four lateral radiographs of 20 male participants were obtained (age = 23.6 ± 2.7 years). Radiographs of participants wearing shoulder pads and helmet were first obtained. The helmet was removed and radiographs of participants with occipital padding were obtained immediately and 20 minutes later and finally without occipital padding. Cobb angle measurements for C2-C6 vertebral segments were determined by an orthopedic spine surgeon blinded to the study's purpose. Intraobserver reliability was determined using intraclass coefficient analysis. Measurements were analyzed using a 1×4 repeated-measures analysis of variance and post hoc pairwise comparisons with Bonferroni correction. Intraobserver analysis showed excellent reliability (intraclass correlation = 1.0; 95% confidence interval [CI], 0.999-1.0). Repeated-measures analysis of variance detected significant differences (F(3,17) = 13.34; P football helmet in the field, occipital padding (along with full body/head immobilization techniques) may be used to limit cervical lordosis, allowing safe delay of shoulder pad removal.

Experimental investigations on the cooling of a motorcycle helmet with phase change material (PCM

Directory of Open Access Journals (Sweden)

Fok S.C.

2011-01-01

Full Text Available The thermal comfort of motorcycle helmet during hot weather is important as it can affect the physiological and psychological condition of the rider. This paper examines the use of phase change material (PCM to cool a motorcycle helmet and presents the experimental investigations on the influences of the simulated solar radiation, wind speed, and heat generation rate on the cooling system. The result shows that the PCM-cooled helmet is able to prolong the thermal comfort period compared to a normal helmet. The findings also indicate that the heat generation from the head is the predominant factor that will affect the PCM melting time. Simulated solar radiation and ram-air due to vehicle motion under adiabatic condition can have very little influences on the PCM melting time. The results suggested that the helmet usage time would be influenced by the amount of heat generated from the head. Some major design considerations based on these findings have been included. Although this investigation focuses on the cooling of a motorcyclist helmet, the findings would also be useful for the development of PCM-cooling systems in other applications.

Investigation of the reasons for not using helmet among motorcyclists in Kerman, Iran.

Science.gov (United States)

Maghsoudi, Aliasghar; Boostani, Dariush; Rafeiee, Manoochehr

2018-03-01

This study was carried out to investigate reasoning and interpretation of motorcyclists for not using helmet utilizing qualitative methodology of 'grounded theory'. The field of the study was Kerman, a cultural-historical city at the south-east of Iran. Participants were 21 young male motorcyclists. Two sampling strategies were used: maximum variation and snowball sampling. To collect data, in-depth, open-ended interviews were conducted. Data analysis yielded seven categories: fatalism; a barrier to social relationships; peer group pressure and negative labelling; messing up the appearance; disturbance in hearing and vision; barrier to normal breathing; and heaviness and superfluity of helmet. Based on the findings of the current study, it could be concluded that socio-cultural contexts, motorcyclists' worldview and partly helmet-related problems are of the main factors which affect motorcycling. Therefore, the studies, policy-makings, and intervening programmes to control injury and to promote safety among motorcyclists should be focused on socio-cultural barriers to helmet use in general and changing the motorcyclists' standpoints toward fatalism in particular. Helmet-related problems should be considered, too.

Pilot vehicle interface on the advanced fighter technology integration F-16

Science.gov (United States)

Dana, W. H.; Smith, W. B.; Howard, J. D.

1986-01-01

This paper focuses on the work load aspects of the pilot vehicle interface in regard to the new technologies tested during AMAS Phase II. Subjects discussed in this paper include: a wide field-of-view head-up display; automated maneuvering attack system/sensor tracker system; master modes that configure flight controls and mission avionics; a modified helmet mounted sight; improved multifunction display capability; a voice interactive command system; ride qualities during automated weapon delivery; a color moving map; an advanced digital map display; and a g-induced loss-of-consciousness and spatial disorientation autorecovery system.

Aerodynamic study of time-trial helmets in cycling racing using CFD analysis.

Science.gov (United States)

Beaumont, F; Taiar, R; Polidori, G; Trenchard, H; Grappe, F

2018-01-23

The aerodynamic drag of three different time-trial cycling helmets was analyzed numerically for two different cyclist head positions. Computational Fluid Dynamics (CFD) methods were used to investigate the detailed airflow patterns around the cyclist for a constant velocity of 15 m/s without wind. The CFD simulations have focused on the aerodynamic drag effects in terms of wall shear stress maps and pressure coefficient distributions on the cyclist/helmet system. For a given head position, the helmet shape, by itself, obtained a weak effect on a cyclist's aerodynamic performance (CFD results have also shown that both helmet shape and head position significantly influence drag forces, pressure and wall shear stress distributions on the whole cyclist's body due to the change in the near-wake behavior and in location of corresponding separation and attachment areas around the cyclist. Copyright © 2017 Elsevier Ltd. All rights reserved.

New ultraportable display technology and applications

Science.gov (United States)

Alvelda, Phillip; Lewis, Nancy D.

1998-08-01

MicroDisplay devices are based on a combination of technologies rooted in the extreme integration capability of conventionally fabricated CMOS active-matrix liquid crystal display substrates. Customized diffraction grating and optical distortion correction technology for lens-system compensation allow the elimination of many lenses and systems-level components. The MicroDisplay Corporation's miniature integrated information display technology is rapidly leading to many new defense and commercial applications. There are no moving parts in MicroDisplay substrates, and the fabrication of the color generating gratings, already part of the CMOS circuit fabrication process, is effectively cost and manufacturing process-free. The entire suite of the MicroDisplay Corporation's technologies was devised to create a line of application- specific integrated circuit single-chip display systems with integrated computing, memory, and communication circuitry. Next-generation portable communication, computer, and consumer electronic devices such as truly portable monitor and TV projectors, eyeglass and head mounted displays, pagers and Personal Communication Services hand-sets, and wristwatch-mounted video phones are among the may target commercial markets for MicroDisplay technology. Defense applications range from Maintenance and Repair support, to night-vision systems, to portable projectors for mobile command and control centers.

Astronauts Parise and Jernigan check helmets prior to training session

Science.gov (United States)

1994-01-01

Attired in training versions of the Shuttle partial-pressure launch and entry suits, payload specialist Dr. Ronald A Parise (left) and astronaut Tamara E. Jernigan, payload commander, check over their helmets prior to a training session. Holding the helmets is suit expert Alan M. Rochford, of NASA. The two were about to join their crew mates in a session of emergency bailout training at JSC's Weightless Environment Training Facility (WETF).

Methods of estimating the effect of integral motorcycle helmets on physiological and psychological performance.

Science.gov (United States)

Bogdan, Anna; Sudoł-Szopińska, Iwona; Luczak, Anna; Konarska, Maria; Pietrowski, Piotr

2012-01-01

This article proposes a method for a comprehensive assessment of the effect of integral motorcycle helmets on physiological and cognitive responses of motorcyclists. To verify the reliability of commonly used tests, we conducted experiments with 5 motorcyclists. We recorded changes in physiological parameters (heart rate, local skin temperature, core temperature, air temperature, relative humidity in the space between the helmet and the surface of the head, and the concentration of O(2) and CO(2) under the helmet) and in psychological parameters (motorcyclists' reflexes, fatigue, perceptiveness and mood). We also studied changes in the motorcyclists' subjective sensation of thermal comfort. The results made it possible to identify reliable parameters for assessing the effect of integral helmets on performance, i.e., physiological factors (head skin temperature, internal temperature and concentration of O(2) and CO(2) under the helmet) and on psychomotor factors (reaction time, attention and vigilance, work performance, concentration and a subjective feeling of mood and fatigue).

The effect of motorcycle helmet fit on estimating head impact kinematics from residual liner crush.

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Bonin, Stephanie J; Gardiner, John C; Onar-Thomas, Arzu; Asfour, Shihab S; Siegmund, Gunter P

2017-09-01

Proper helmet fit is important for optimizing head protection during an impact, yet many motorcyclists wear helmets that do not properly fit their heads. The goals of this study are i) to quantify how a mismatch in headform size and motorcycle helmet size affects headform peak acceleration and head injury criteria (HIC), and ii) to determine if peak acceleration, HIC, and impact speed can be estimated from the foam liner's maximum residual crush depth or residual crush volume. Shorty-style helmets (4 sizes of a single model) were tested on instrumented headforms (4 sizes) during linear impacts between 2.0 and 10.5m/s to the forehead region. Helmets were CT scanned to quantify residual crush depth and volume. Separate linear regression models were used to quantify how the response variables (peak acceleration (g), HIC, and impact speed (m/s)) were related to the predictor variables (maximum crush depth (mm), crush volume (cm 3 ), and the difference in circumference between the helmet and headform (cm)). Overall, we found that increasingly oversized helmets reduced peak headform acceleration and HIC for a given impact speed for maximum residual crush depths less than 7.9mm and residual crush volume less than 40cm 3 . Below these levels of residual crush, we found that peak headform acceleration, HIC, and impact speed can be estimated from a helmet's residual crush. Above these crush thresholds, large variations in headform kinematics are present, possibly related to densification of the foam liner during the impact. Copyright © 2017 Elsevier Ltd. All rights reserved.

Facial asymmetry correction with moulded helmet therapy in infants with deformational skull base plagiocephaly.

Science.gov (United States)

Kreutz, Matthias; Fitze, Brigitte; Blecher, Christoph; Marcello, Augello; Simon, Ruben; Cremer, Rebecca; Zeilhofer, Hans-Florian; Kunz, Christoph; Mayr, Johannes

2018-01-01

The recommendation issued by the American Academy of Pediatrics in the early 1990s to position infants on their back during sleep to prevent sudden infant death syndrome (SIDS) has dramatically reduced the number of deaths due to SIDS but has also markedly increased the prevalence of positional skull deformation in infants. Deformation of the base of the skull occurs predominantly in very severe deformational plagiocephaly and is accompanied by facial asymmetry, as well as an altered ear position, called ear shift. Moulded helmet therapy has become an accepted treatment strategy for infants with deformational plagiocephaly. The aim of this study was to determine whether facial asymmetry could be corrected by moulded helmet therapy. In this retrospective, single-centre study, we analysed facial asymmetry of 71 infants with severe deformational plagiocephaly with or without deformational brachycephaly who were undergoing moulded helmet therapy between 2009 and 2013. Computer-assisted, three-dimensional, soft-tissue photographic scanning was used to record the head shape before and after moulded helmet therapy. The distance between two landmarks in the midline of the face (i.e., root of the nose and nasal septum) and the right and left tragus were measured on computer-generated indirect and objective 3D photogrammetry images. A quotient was calculated between the two right- and left-sided distances to the midline. Quotients were compared before and after moulded helmet therapy. Infants without any therapy served as a control group. The median age of the infants before onset of moulded helmet therapy was 5 months (range 3-16 months). The median duration of moulded helmet therapy was 5 months (range 1-16 months). Comparison of the pre- and post-treatment quotients of the left vs. right distances measured between the tragus and root of the nose (n = 71) and nasal septum (n = 71) revealed a significant reduction of the asymmetry (Tragus-Nasion-Line Quotient: 0

A Decision Analysis Framework for Evaluation of Helmet Mounted Display Alternatives for Fighter Aircraft

Science.gov (United States)

2014-12-26

Figure 19 : Pilot Satisfaction Value Function................................................................... 76 Figure 20 : HMD Optic Designs...This often results in high workload and complicated multitasking environments which can be overwhelming, forcing the operator to share attention...safety and survivability of a pilot , as well as enhance their lethality by allowing line of sight steering of weapons and sensors. However, if

INTER LABORATORY COMBAT HELMET BLUNT IMPACT TEST METHOD COMPARISON

Science.gov (United States)

2018-03-26

data by Instrumentation for Impact  Test , SAE standard J211‐1 [4]. Although the entire curve is collected, the interest of this  project  team  solely...HELMET BLUNT IMPACT TEST METHOD COMPARISON by Tony J. Kayhart Charles A. Hewitt and Jonathan Cyganik March 2018 Final...INTER-LABORATORY COMBAT HELMET BLUNT IMPACT TEST METHOD COMPARISON 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR

Testing and evaluation of a wearable augmented reality system for natural outdoor environments

Science.gov (United States)

Roberts, David; Menozzi, Alberico; Cook, James; Sherrill, Todd; Snarski, Stephen; Russler, Pat; Clipp, Brian; Karl, Robert; Wenger, Eric; Bennett, Matthew; Mauger, Jennifer; Church, William; Towles, Herman; MacCabe, Stephen; Webb, Jeffrey; Lupo, Jasper; Frahm, Jan-Michael; Dunn, Enrique; Leslie, Christopher; Welch, Greg

2013-05-01

This paper describes performance evaluation of a wearable augmented reality system for natural outdoor environments. Applied Research Associates (ARA), as prime integrator on the DARPA ULTRA-Vis (Urban Leader Tactical, Response, Awareness, and Visualization) program, is developing a soldier-worn system to provide intuitive `heads-up' visualization of tactically-relevant geo-registered icons. Our system combines a novel pose estimation capability, a helmet-mounted see-through display, and a wearable processing unit to accurately overlay geo-registered iconography (e.g., navigation waypoints, sensor points of interest, blue forces, aircraft) on the soldier's view of reality. We achieve accurate pose estimation through fusion of inertial, magnetic, GPS, terrain data, and computer-vision inputs. We leverage a helmet-mounted camera and custom computer vision algorithms to provide terrain-based measurements of absolute orientation (i.e., orientation of the helmet with respect to the earth). These orientation measurements, which leverage mountainous terrain horizon geometry and mission planning landmarks, enable our system to operate robustly in the presence of external and body-worn magnetic disturbances. Current field testing activities across a variety of mountainous environments indicate that we can achieve high icon geo-registration accuracy (<10mrad) using these vision-based methods.

The effect of viewing a virtual environment through a head-mounted display on balance.

Science.gov (United States)

Robert, Maxime T; Ballaz, Laurent; Lemay, Martin

2016-07-01

In the next few years, several head-mounted displays (HMD) will be publicly released making virtual reality more accessible. HMD are expected to be widely popular at home for gaming but also in clinical settings, notably for training and rehabilitation. HMD can be used in both seated and standing positions; however, presently, the impact of HMD on balance remains largely unknown. It is therefore crucial to examine the impact of viewing a virtual environment through a HMD on standing balance. To compare static and dynamic balance in a virtual environment perceived through a HMD and the physical environment. The visual representation of the virtual environment was based on filmed image of the physical environment and was therefore highly similar. This is an observational study in healthy adults. No significant difference was observed between the two environments for static balance. However, dynamic balance was more perturbed in the virtual environment when compared to that of the physical environment. HMD should be used with caution because of its detrimental impact on dynamic balance. Sensorimotor conflict possibly explains the impact of HMD on balance. Copyright © 2016 Elsevier B.V. All rights reserved.

The impact of mandatory helmet law on the outcome of maxillo facial trauma: a comparative study in kerala.

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Usha, M; Ravindran, V; Soumithran, C S; Ravindran Nair, K S

2014-06-01

Motorcyclists comprise the majority of road-traffic victims in low and middle income countries,and consequently, the majority of the road-traffic victims globally. Simple measures can be taken to make safer on the roads, which include enforcement of safety measures like seat belt and helmets. The compulsory Helmet law was enforced in Kerala on 18/06/07. Resistance to legislation on motorcycle helmets still coexists world wide with debate on the effectiveness of helmets. In an attempt to analyze the protective effect of helmets on facial injuries a comparative study was conducted in Government Dental College, Calicut, which is a major trauma centre in northern Kerala. Data for the present study was obtained from the patients who have reported to the Emergency Department of Oral and Maxillofacial Surgery, Government Dental College, Calicut, for a period of 6 months immediately after the implementation of strict helmet rule in Kerala. For the study all patients with a history of nonfatal motor cycle accident sustaining facial injuries were included. The results were compared with the study conducted in the same institution in the pre law period. The study demonstrates the protective effect of motorcycle helmets in decreasing the morbidity of maxillofacial trauma.There was a marked decrease in incidence of motorcycle-related injuries, remarkable increase in helmet usage and better outcome in helmeted individuals in the post law period. Road traffic injury control is a public health problem. Health and medical professionals have an ethical responsibility to educate and arrange for the safety of individuals. Helmets are effective in preventing or reducing the severity of motorcycle-related injuries and in a developing country like India, enforced mandatory motor cycle helmet law is potentially one of the most cost effective interventions available.

A DESCRIPTIVE STUDY OF PATTERN OF FATAL HEAD INJURY IN HELMETED AND NONHELMETED VICTIMS OF TWO WHEELER ACCIDENTS

Directory of Open Access Journals (Sweden)

P. A. Sheeju

2016-07-01

Full Text Available BACKGROUND Motor vehicle crashes are a major cause of fatality all over the world. By 2020, motor vehicle injury is projected to become the third leading contributor to the global burden of disease in the world. Motor cyclists are about 25 times more likely than car occupants to die in Road Traffic Accidents. Data on the incidence and types of crashes is required to guide safety policy. Knowledge of how injuries are caused and of what type they are of valuable instrument for identifying interventions and monitoring the effectiveness of intervention. The present study was done to find out the factors that contribute for motor cycle crashes and to study the injury pattern seen in helmeted and non-helmeted victims. MATERIAL AND METHODS Victims of two wheeler accidents brought for autopsy in a Govt. Medical College were studied from October 2010 to August 2011. Two wheelers include motor cycles, scooters and mopeds. Bicycles were excluded from the study. Accidents include all types; against all types of vehicles running on the road, collision with any object, surface or any animal or fall from vehicle. The details of the accident were collected in a printed proforma from relative/witnesses and from police officials. The injuries were entered in the specific columns of proforma. Data was analysed with MS Excel. RESULTS Death due to head injury is more in non-helmeted (52.5% compared to helmeted drivers (43.8 % whereas injury to chest and abdomen and limbs are more in helmeted. Combination of injuries (Head+Chest+Abdomen predominated in helmeted drivers (18.8% compared to 5% in non-helmeted drivers. Spinal injuries were more in helmeted than in non-helmeted. CONCLUSION The pattern of head injury was analysed in detail in helmeted and non-helmeted drivers. This will help in detailing of pattern of head injury in both groups.

The Association Between Risk-taking Behavior and Helmet Use Among Motorcyclist

Science.gov (United States)

Trinh, Tu Anh; Phuong Linh Le, Thi

2018-04-01

The central aim of the research was to examine speeding behavior without helmet wearing among motorcycle riders in Ho Chi Minh City. The research model expanded the Theory of Planned Behavior by both psychological flow theory and sensation-seeking. 268 motorcyclists were involved in the research. A Confirmatory factor analysis and a Structural equation modeling were employed for model specification. The findings indicated a significant effect between predictors and the intention of speeding without helmet wearing. In addition, there was direct relation between intention and actual behavior. Also, sensation-seeking proved to be important in moderating predictors between the low-sensation-seeking motorcyclists and high-sensation-seeking ones. A deeper understanding of why motorcycle riders exceed the speed limit without wearing helmet played key role in changing their behavior.

[Comfort and noise level in infants with helmet interface].

Science.gov (United States)

Medina, A; Alvarez Fernández, P; Rey Galán, C; Álvarez Mendiola, P; Álvarez Blanco, S; Vivanco Allende, A

2015-10-01

To evaluate comfort and noise intensity using the COMFORT scale in infants who receive respiratory support with a helmet interface. An observational descriptive study was conducted on all infants (1 to 12 months of age) admitted to a PICU from November 1st 2013 to March 31st 2014 and who received non-invasive ventilation with a helmet interface. Tolerance to the interface was assessed by use of the COMFORT scale. The intensity of the noise to which the infants were exposed was measured with a TES1350A HIBOK 412 sound-level meter. Three measurements were made every day. Twenty seven patients with bronchiolitis (median age: 54 days; range: 10 to 256) were included. Median COMFORT score in the first day was 21 points (14 - 28). An increase in patient comfort was found with a gradual decrease in the scores, with a maximum reduction of 22% from the first hours (score of 22) to the fifth day (score of 18). The minimum sound intensity registered was 42dB, and the maximum was 78dB. Background noise intensity was associated with noise intensity in the helmet. No differences were observed in COMFORT score and noise intensity between ventilator devices. Helmet interface was well tolerated by infants. COMFORT score results are an indicator that infants were comfortable or very comfortable. The measured noise intensity was in the safe range permitted by World Health Organization. Copyright © 2014 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

Breath-hold monitoring and visual feedback for radiotherapy using a charge-coupled device camera and a head-mounted display. System development and feasibility

International Nuclear Information System (INIS)

Yoshitake, Tadamasa; Nakamura, Katsumasa; Shioyama, Yoshiyuki

2008-01-01

The aim of this study was to present the technical aspects of the breath-hold technique with respiratory monitoring and visual feedback and to evaluate the feasibility of this system in healthy volunteers. To monitor respiration, the vertical position of the fiducial marker placed on the patient's abdomen was tracked by a machine vision system with a charge-coupled device camera. A monocular head-mounted display was used to provide the patient with visual feedback about the breathing trace. Five healthy male volunteers were enrolled in this study. They held their breath at the end-inspiration and the end-expiration phases. They performed five repetitions of the same type of 15-s breath-holds with and without a head-mounted display, respectively. A standard deviation of five mean positions of the fiducial marker during a 15-s breath-hold in each breath-hold type was used as the reproducibility value of breath-hold. All five volunteers well tolerated the breath-hold maneuver. For the inspiration breath-hold, the standard deviations with and without visual feedback were 1.74 mm and 0.84 mm, respectively (P=0.20). For the expiration breath-hold, the standard deviations with and without visual feedback were 0.63 mm and 0.96 mm, respectively (P=0.025). Our newly developed system might help the patient achieve improved breath-hold reproducibility. (author)

List of U.S. Army Research Institute Research and Technical Publications for Public Release/Unlimited Distribution, Fiscal Year 2010

Science.gov (United States)

2011-04-01

Training System ( VSTS ) is a network of nine individual immersive simulators with Helmet-Mounted Displays (HMDs), and a command station for controlling...computer generated entities. The VSTS includes both tethered and wearable simulators. The VSTS was evaluated with two squads (9 members per squad) of...with individual simulators and the network interfered with the conduct of the evaluation and probably affected Soldiers’ ratings of the VSTS

Automatic helmet-wearing detection for law enforcement using CCTV cameras

Science.gov (United States)

Wonghabut, P.; Kumphong, J.; Satiennam, T.; Ung-arunyawee, R.; Leelapatra, W.

2018-04-01

The objective of this research is to develop an application for enforcing helmet wearing using CCTV cameras. The developed application aims to help law enforcement by police, and eventually resulting in changing risk behaviours and consequently reducing the number of accidents and its severity. Conceptually, the application software implemented using C++ language and OpenCV library uses two different angle of view CCTV cameras. Video frames recorded by the wide-angle CCTV camera are used to detect motorcyclists. If any motorcyclist without helmet is found, then the zoomed (narrow-angle) CCTV is activated to capture image of the violating motorcyclist and the motorcycle license plate in real time. Captured images are managed by database implemented using MySQL for ticket issuing. The results show that the developed program is able to detect 81% of motorcyclists on various motorcycle types during daytime and night-time. The validation results reveal that the program achieves 74% accuracy in detecting the motorcyclist without helmet.

Influence of humidification on comfort during noninvasive ventilation with a helmet.

Science.gov (United States)

Ueta, Kazuyoshi; Tomita, Toshiji; Uchiyama, Akinori; Ohta, Noriyuki; Iguchi, Naoya; Goto, Yukiko; Fujino, Yuji

2013-05-01

To evaluate optimal humidifier water temperature when using a helmet for noninvasive ventilation. Twenty-eight healthy individuals underwent 8 cm H2O CPAP ventilation with FIO2 of 0.21 and 0.5. Each was sequentially tested in the following order: using the helmet without humidification at ambient temperature; with humidification with unheated chamber water; and with humidification with the chamber water at 31°C, 34°C, and 37°C. At each setting, after a 20 min stabilization period, measurements were taken. Comfort level at each setting was evaluated using a visual analog scale rated zero (least comfortable) to 10 (most comfortable). Temperature and relative and absolute humidity inside the helmet increased; however, the comfort scores significantly decreased as the humidification chamber water temperature increased. Regardless of the FIO2, statistically significantly highest comfort scores were obtained when humidification water, with and without active humidification, was at ambient temperature. Unacceptable absolute humidity was obtained only without humidification at room temperature when FIO2 was 0.5. With the clinical use of a helmet, for patient comfort and mucosal humidification during CPAP, the most desirable conditions are likely to be obtained by humidifying without heating, that is by leaving the water in the humidifier chamber at room temperature.

Simulated laparoscopy using a head-mounted display vs traditional video monitor: an assessment of performance and muscle fatigue.

Science.gov (United States)

Maithel, S K; Villegas, L; Stylopoulos, N; Dawson, S; Jones, D B

2005-03-01

The direction of visual gaze may be an important ergonomic factor that affects operative performance. We designed a study to determine whether a head-mounted display (HMD) worn by the surgeon would improve task performance and/or reduce muscle fatigue during a laparoscopic task when compared to the use of a traditional video monitor display (VMD). Surgical residents (n = 30) were enrolled in the study. A junior group, consisting of 15 postgraduate year (PGY) = 1 subjects with no previous laparoscopic experience, and a senior group, consisting of 15 PGY 4 and PGY 5 subjects with experience, completed a laparoscopic task that was repeated four times using the Computer Enhanced Laparoscopic Training System (CELTS). Groups alternated between using the HMD with the task placed in a downward frontal position and the VMD with the task at a 30 degrees lateral angle. The CELTS module assessed task completion time, depth perception, path length of instruments, response orientation, motion smoothness; the system then generated an overall score. Electromyography (EMG) was used to record sternocleidomastoid muscle activity. Display preference was surveyed. The senior residents performed better than the junior residents overall on all parameters (p < 0.05) except for motion smoothness, where there was no difference. In both groups, the HMD significantly improved motion smoothness when compared to the VMD (p < 0.05). All other parameters were equal. There was less muscle fatigue when using the VMD (p < 0.05). We found that 66% of the junior residents but only 20% of the senior residents preferred the HMD. The CELTS module demonstrated evidence of construct validity by differentiating the performances of junior and senior residents. By aligning the surgeon's visual gaze with the instruments, HMD improved smoothness of motion. Experienced residents preferred the traditional monitor display. Although the VMD produced less muscle fatigue, inexperienced residents preferred the HMD

Survey of symbology for aeronautical charts and electronic displays : navigation aids, airports, lines, and linear patterns

Science.gov (United States)

2008-09-01

This industry survey documents the symbols for navigation aids, airports, lines, and linear patterns currently in use by avionics manufactureres and chart providers for depicting aeronautical charting information. Nine avionics display manufacturers ...

Design of a Helmet Liner for Improved Low Velocity Impact Protection

Science.gov (United States)

2013-05-01

FIGURE 14. MONORAIL DROP TEST WITH DOT-SIZE C HEADFORM AND HEMISPHERICAL ANVIL ........................... 14  FIGURE 15. ACH PAD CONFIGURATION. LEFT...materials. In this project, the monorail drop test device, used for the helmeted headform drop test, was modified for material testing as shown in Figure...a guided free fall drop test using a monorail drop test apparatus as shown in Figure 14. All helmets tested in this study were ACH-Size Large and

Examination of factors associated with use rates after transition from a universal to partial motorcycle helmet use law.

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Russo, Brendan J; Barrette, Timothy P; Morden, Jeffery; Savolainen, Peter T; Gates, Timothy J

2017-01-02

Motorcycle riders account for a disproportionately high number of traffic injuries and fatalities compared to occupants of other vehicle types. Though research has demonstrated the benefits of helmet use in preventing serious and fatal injuries in the event of a crash, helmet use has remained relatively stable in the United States, where the most recent national estimates show a 64% use rate. Use rates have been markedly lower among those states that do not have a universal helmet law for all riders. In 2012, the state of Michigan repealed its longstanding mandatory helmet use law. In order to gain insights as to the effects of this legislative change, a study was conducted to examine short-term changes in helmet use and identify factors associated with use rates. A statewide direct observation survey was conducted 1 year after the transition from a universal helmet law to a partial helmet law. A random parameters logistic regression model was estimated to identify motorcyclist, roadway, and environmental characteristics associated with helmet use. This modeling framework accounts for both intravehicle correlation (between riders and passengers on the same motorcycle) as well as unobserved heterogeneity across riders due to important unobserved factors. Helmet use was shown to vary across demographic segments of the motorcyclist population. Use rates were higher among Caucasian riders, as well as among those age 60 and above. No significant difference was observed between male and female riders. Use was also found to vary geographically, temporally, and with respect to various environmental characteristics. Geographically, helmet use rates tended to be correlated with historical restraint use trends, which may be reflective of riding environment and general differences in the riding population. To this end, rates were also highly variable based upon the type of motorcycle and whether the motorcyclist was wearing high-visibility gear. The study results demonstrate

HElmet therapy Assessment in infants with Deformed Skulls (HEADS: protocol for a randomised controlled trial

Directory of Open Access Journals (Sweden)

van Wijk Renske M

2012-07-01

Full Text Available Abstract Background In The Netherlands, helmet therapy is a commonly used treatment in infants with skull deformation (deformational plagiocephaly or deformational brachycephaly. However, evidence of the effectiveness of this treatment remains lacking. The HEADS study (HElmet therapy Assessment in Deformed Skulls aims to determine the effects and costs of helmet therapy compared to no helmet therapy in infants with moderate to severe skull deformation. Methods/design Pragmatic randomised controlled trial (RCT nested in a cohort study. The cohort study included infants with a positional preference and/or skull deformation at two to four months (first assessment. At 5 months of age, all children were assessed again and infants meeting the criteria for helmet therapy were asked to participate in the RCT. Participants were randomly allocated to either helmet therapy or no helmet therapy. Parents of eligible infants that do not agree with enrolment in the RCT were invited to stay enrolled for follow up in a non-randomisedrandomised controlled trial (nRCT; they were then free to make the decision to start helmet therapy or not. Follow-up assessments took place at 8, 12 and 24 months of age. The main outcome will be head shape at 24 months that is measured using plagiocephalometry. Secondary outcomes will be satisfaction of parents and professionals with the appearance of the child, parental concerns about the future, anxiety level and satisfaction with the treatment, motor development and quality of life of the infant. Finally, compliance and costs will also be determined. Discussion HEADS will be the first study presenting data from an RCT on the effectiveness of helmet therapy. Outcomes will be important for affected children and their parents, health care professionals and future treatment policies. Our findings are likely to influence the reimbursement policies of health insurance companies. Besides these health outcomes, we will be able to

Experiments in teleoperator and autonomous control of space robotic vehicles

Science.gov (United States)

Alexander, Harold L.

1991-01-01

A program of research embracing teleoperator and automatic navigational control of freely flying satellite robots is presented. Current research goals include: (1) developing visual operator interfaces for improved vehicle teleoperation; (2) determining the effects of different visual interface system designs on operator performance; and (3) achieving autonomous vision-based vehicle navigation and control. This research program combines virtual-environment teleoperation studies and neutral-buoyancy experiments using a space-robot simulator vehicle currently under development. Visual-interface design options under investigation include monoscopic versus stereoscopic displays and cameras, helmet-mounted versus panel-mounted display monitors, head-tracking versus fixed or manually steerable remote cameras, and the provision of vehicle-fixed visual cues, or markers, in the remote scene for improved sensing of vehicle position, orientation, and motion.

Determinants of helmet use behaviour among employed motorcycle riders in Yazd, Iran based on theory of planned behaviour.

Science.gov (United States)

Ali, Mehri; Saeed, Mazloomy Mahmoodabad Seyed; Ali, Morowatisharifabad Mohammad; Haidar, Nadrian

2011-09-01

This paper reports on predictors of helmet use behaviour, using variables based on the theory of planned behaviour model among the employed motorcycle riders in Yazd-Iran, in an attempt to identify influential factors that may be addressed through intervention efforts. In 2007, a cluster random sample of 130 employed motorcycle riders in the city of Yazd in central Iran, participated in the study. Appropriate instruments were designed to measure the variables of interest (attitude, subjective norms, perceived behaviour control, intention along with helmet use behaviour). Reliability and validity of the instruments were examined and approved. The statistical analysis of the data included descriptive statistics, bivariate correlations, and multiple regression. Based on the results, 56 out of all the respondents (43.1%) had history of accident by motorcycle. Of these motorcycle riders only 10.7% were wearing their helmet at the time of their accident. Intention and perceived behavioural control showed a significant relationship with helmet use behaviour and perceived behaviour control was the strongest predictor of helmet use intention, followed by subjective norms, and attitude. It was found that that helmet use rate among motorcycle riders was very low. The findings of present study provide a preliminary support for the TPB model as an effective framework for examining helmet use in motorcycle riders. Understanding motorcycle rider's thoughts, feelings and beliefs about helmet use behaviour can assist intervention specialists to develop and implement effective programs in order to promote helmet use among motorcycle riders. Copyright © 2010 Elsevier Ltd. All rights reserved.

Motorcycle helmet use and the risk of head, neck, and fatal injury: Revisiting the Hurt Study.

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Rice, Thomas M; Troszak, Lara; Ouellet, James V; Erhardt, Taryn; Smith, Gordon S; Tsai, Bor-Wen

2016-06-01

Most studies find strong evidence that motorcycle helmets protect against injury, but a small number of controversial studies have reported a positive association between helmet use and neck injury. The most commonly cited paper is that of Goldstein (1986). Goldstein obtained and reanalyzed data from the Hurt Study, a prospective, on-scene investigation of 900 motorcycle collisions in the city of Los Angeles. The Goldstein results have been adopted by the anti-helmet community to justify resistance to compulsory motorcycle helmet use on the grounds that helmets may cause neck injuries due to their mass. In the current study, we replicated Goldstein's models to understand how he obtained his unexpected results, and we then applied modern statistical methods to estimate the association of motorcycle helmet use with head injury, fatal injury, and neck injury among collision-involved motorcyclists. We found Goldstein's analysis to be critically flawed due to improper data imputation, modeling of extremely sparse data, and misinterpretation of model coefficients. Our new analysis showed that motorcycle helmets were associated with markedly lower risk of head injury (RR 0.40, 95% CI 0.31-0.52) and fatal injury (RR 0.44, 95% CI 0.26-0.74) and with moderately lower but statistically significant risk of neck injury (RR 0.63, 95% CI 0.40-0.99), after controlling for multiple potential confounders. Copyright © 2016 Elsevier Ltd. All rights reserved.

Motorcycle helmet type and the risk of head injury and neck injury during motorcycle collisions in California.

Science.gov (United States)

Erhardt, Taryn; Rice, Thomas; Troszak, Lara; Zhu, Motao

2016-01-01

The use of novelty motorcycle helmets is often prompted by beliefs that wearing a standard helmet can contribute to neck injury during traffic collisions. The goal of this analysis was to examine the association between helmet type and neck injury risk and the association between helmet type and head injury. Data were collected during the investigation of motorcycle collisions of any injury severity by the California Highway Patrol (CHP) and 83 local law enforcement agencies in California between June 2012 and July 2013. We estimated head injury and neck injury risk ratios from data on 7051 collision-involved motorcyclists using log-binomial regression. Helmet type was strongly associated with head injury occurrence but was not associated with the occurrence of neck injury. Rider age, rider alcohol use, and motorcycle speed were strong, positive predictors of both head and neck injury. Interventions to improve motorcycle helmet choice and to counteract misplaced concerns surrounding neck injury risk are likely to lead to reductions in head injury, brain injury, and death. Copyright © 2015 Elsevier Ltd. All rights reserved.

Influence of socioeconomic status on the effectiveness of bicycle helmet legislation for children: a prospective observational study.

Science.gov (United States)

Parkin, Patricia C; Khambalia, Amina; Kmet, Leanne; Macarthur, Colin

2003-09-01

To evaluate the influence of average family income in a geographic area on the effectiveness of helmet legislation on observed helmet use by children (5-14 years). The study was conducted in East York, a health district of Metropolitan Toronto, in collaboration with the East York Health Unit. In 1996, the total population was 107 822, 11 340 of which were children 5 to 14 years. Census data were used to group the 21 census tracts in East York into 7 geographically distinct areas. The boundaries of these areas are natural barriers to travel, such as expressways, ravines, railway tracks, and hydroelectric power lines. The areas were also ranked according to average family income (based on Statistics Canada data). For analytical purposes, areas were defined as low-, mid-, and high-income areas. Census data profiles of the areas have been previously described. For each consecutive year from 1990 to 1997 inclusive, direct observations of children riding bicycles in East York during the months of April through October were made. In 1995, observations were completed before the introduction of the law on October 1, 1995. Only children who were between 5 and 14 years of age and riding a 2-wheeled bicycle were included in the study. In total, 111 sites across all 7 areas were selected for observation. Observational sites included school yards of all elementary and middle schools (kindergarten to grade 8) and all parks in East York. In addition, 5 major intersections and 5 residential streets from each area were randomly selected. Observers were trained and used a standardized data collection form. A pilot study showed that the data collected by observers were reliable and valid. Observers remained at each site for 1 hour and collected data on helmet use and sex. Ethical approval for the study was obtained from the Hospital for Sick Children Research Ethics Board, the East York Board of Education, and the Metropolitan Separate School Board. The proportion of children who were

Helmet "tang" from the Metropolitan Museum of Art (New York City, United States. Features of Construction, Design and Operational Use

Directory of Open Access Journals (Sweden)

Leonid A. Bobrov

2016-12-01

Full Text Available The article discusses iron helmet (No. 36.25.115, which is stored in the Metropolitan Museum of art (New York City, United States. For the first time this helmet was published and analyzed by American scientists G. C. Stone and D.G. Alexander. The analysis showed that the Bowl was made by Turkish masters of the XVII century and backplate and the hoop is added to the helmet in 1781–1782 D.G. Alexander speculated that the helmet belonged to the Warrior of the Crimean Khanate. Dating the helmet does not raise objections. However, the attribution of a helmet requires some clarification. Analysis of the design of the helmet and decoration revealed that backplate, hoop and Aventail from iron rings added to Bowl in 1781–1782, were manufactured by Circassian craftsmen living in the Northern Caucasus or in Crimea. For the decoration of the helmet has been used typical Circassian ornaments: "sieve", cherkessian floral pattern, geometric shapes, triangular in shape, "gear", etc. During Assembly of the helmet were applied characteristic of Circassian gunsmiths technological solutions: using as a basis the bowl old-style helmet, tapered Finial with a ring for a decorative plume, hoop with four plates, ringed with aventail lip to protect the forehead, etc. In Circassia similar headgear worn were known as tang (from the Arabic. "Taj", i.e., the "Crown". In the XVII–XVIII centuries. they willingly purchased representatives of Crimean Tatar nobility. Similar in design and system design helmets Circassian production belonged to the highest aristocracy of the Crimean Khanate, are stored in Museum and private collections in Poland, Turkey and the United States. The inscription "Bekmurun" on the hoop from the Metropolitan helmet suggests that it was manufactured on request of Kabardian Bekmur princely heir (Bekmurziny, which moved from Circassia in Crimea, 1737. The popularity of tang type helmets among the aristocracy of North Caucasus and Crimea were due not

Feasibility of nitric oxide administration by neonatal helmet-CPAP: a bench study.

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Trevisanuto, Daniele; Doglioni, Nicoletta; Micaglio, Massimo; Zanardo, Vincenzo

2007-09-01

Inhaled nitric oxide (NO) may have a role in the treatment of preterm infants with respiratory failure. We evaluated the feasibility of administering NO therapy by a new continuous positive airway pressure (CPAP) system (neonatal helmet-CPAP). While maintaining a constant total flow of 8, 10, and 12 l.min(-1), NO concentrations were progressively increased to 5, 10, 20, and 40 p.p.m. in the neonatal helmet-CPAP pressure chamber (5 cmH2O). NO, NO2, and O2 concentrations were measured in the pressure chamber and the immediate external environment. In the chamber, NO2 levels remained low (neonatal helmet-CPAP system. This method allows the delivery of accurate NO levels and high O2 concentrations avoiding NO2 accumulation. Further experimental and clinical studies are needed.

Societal cost of traumatic brain injury: A comparison of cost-of-injuries related to biking with and without helmet use.

Science.gov (United States)

Costa, Camille K; Dagher, Jehane H; Lamoureux, Julie; de Guise, Elaine; Feyz, Mitra

2015-01-01

The goal of this study is to determine if a difference in societal costs exists from traumatic brain injuries (TBI) in patients who wear helmets compared to non-wearers. This is a retrospective cost-of-injury study of 128 patients admitted to the Montreal General Hospital (MGH) following a TBI that occurred while cycling between 2007-2011. Information was collected from Quebec Trauma Registry. The independent variables collected were socio-demographic, helmet status, clinical and neurological patient information. The dependent variables evaluated societal costs. The median costs of hospitalization were significantly higher (p = 0.037) in the no helmet group ($7246.67 vs. $4328.17). No differences in costs were found for inpatient rehabilitation (p = 0.525), outpatient rehabilitation (p = 0.192), loss of productivity (p = 0.108) or death (p = 1.000). Overall, the differences in total societal costs between the helmet and no helmet group were not significantly different (p = 0.065). However, the median total costs for patients with isolated TBI in the non-helmet group ($22, 232.82) was significantly higher (p = 0.045) compared to the helmet group ($13, 920.15). Cyclists sustaining TBIs who did not wear helmets in this study were found to cost society nearly double that of helmeted cyclists.

The effect of helmet use on injury severity and crash circumstances in skiers and snowboarders.

Science.gov (United States)

Hagel, Brent; Pless, I Barry; Goulet, Claude; Platt, Robert; Robitaille, Yvonne

2005-01-01

The aim of this study was to examine the effect of helmet use on non-head-neck injury severity and crash circumstances in skiers and snowboarders. We used a matched case-control study over the November 2001 to April 2002 winter season. 3295 of 4667 injured skiers and snowboarders reporting to the ski patrol at 19 areas in Quebec with non-head, non-neck injuries agreed to participate. Cases included those evacuated by ambulance, admitted to hospital, with restriction of normal daily activities (NDAs) >6 days, with non-helmet equipment damage, fast self-reported speed, participating on a more difficult run than usual, and jumping-related injury. Controls were injured participants without severe injuries or high-energy crash circumstances and were matched to cases on ski area, activity, day, age, and sex. Conditional logistic regression was used to relate each outcome to helmet use. There was no evidence that helmet use increased the risk of severe injury or high-energy crash circumstances. The results suggest that helmet use in skiing and snowboarding is not associated with riskier activities that lead to non-head-neck injuries.

Impact of helmet use on traumatic brain injury from road traffic accidents in Cambodia.

Science.gov (United States)

Gupta, Saksham; Klaric, Katherine; Sam, Nang; Din, Vuthy; Juschkewitz, Tina; Iv, Vycheth; Shrime, Mark G; Park, Kee B

2018-01-02

Rapid urbanization and motorization without corresponding increases in helmet usage have made traumatic brain injury due to road traffic accidents a major public health crisis in Cambodia. This analysis was conducted to quantify the impact of helmets on severity of injury, neurosurgical indication, and functional outcomes at discharge for motorcycle operators who required hospitalization for a traumatic brain injury following a road traffic accident in Cambodia. The medical records of 491 motorcycle operators who presented to a major tertiary care center in Cambodia with traumatic brain injury were retrospectively analyzed using multivariate logistic regression. The most common injuries at presentation were contusions (47.0%), epidural hematomas (30.1%), subdural hematomas (27.9%), subarachnoid hemorrhages (12.4%), skull fractures (21.4%), and facial fractures (18.5%). Moderate-to-severe loss of consciousness was present in 36.3% of patients. Not wearing a helmet was associated with an odds ratio of 2.20 (95% confidence interval [CI], 1.15-4.22) for presenting with moderate to severe loss of consciousness compared to helmeted patients. Craniotomy or craniectomy was indicated for evacuation of hematoma in 20.0% of cases, and nonhelmeted patients had 3.21-fold higher odds of requiring neurosurgical intervention (95% CI, 1.25-8.27). Furthermore, lack of helmet usage was associated with 2.72-fold higher odds of discharge with functional deficits (95% CI, 1.14-6.49). In total, 30.1% of patients were discharged with severe functional deficits. Helmets demonstrate a protective effect and may be an effective public health intervention to significantly reduce the burden of traumatic brain injury in Cambodia and other developing countries with increasing rates of motorization across the world.

Public bike sharing in New York City: helmet use behavior patterns at 25 Citi Bike™ stations.

Science.gov (United States)

Basch, Corey H; Ethan, Danna; Zybert, Patricia; Afzaal, Sarah; Spillane, Michael; Basch, Charles E

2015-06-01

Urban public bicycle sharing programs are on the rise in the United States. Launched in 2013, NYC's public bicycle share program, Citi Bike™ is the fastest growing program of its kind in the nation, with nearly 100,000 members and more than 330 docking stations across Manhattan and Brooklyn. The purpose of this study was to assess helmet use behavior among Citi Bike™ riders at 25 of the busiest docking stations. The 25 Citi Bike™ Stations varied greatly in terms of usage: total number of cyclists (N = 96-342), commute versus recreation (22.9-79.5% commute time riders), weekday versus weekend (6.0-49.0% weekend riders). Helmet use ranged between 2.9 and 29.2% across sites (median = 7.5 %). A total of 4,919 cyclists were observed, of whom 545 (11.1%) were wearing helmets. Incoming cyclists were more likely to wear helmets than outgoing cyclists (11.0 vs 5.9%, p = .000). NYC's bike share program endorses helmet use, but relies on education to encourage it. Our data confirm that, to date, this strategy has not been successful.

Assessing balance through the use of a low-cost head-mounted display in older adults: a pilot study.

Science.gov (United States)

Saldana, Santiago J; Marsh, Anthony P; Rejeski, W Jack; Haberl, Jack K; Wu, Peggy; Rosenthal, Scott; Ip, Edward H

2017-01-01

As the population ages, the prevention of falls is an increasingly important public health problem. Balance assessment forms an important component of fall-prevention programs for older adults. The recent development of cost-effective and highly responsive virtual reality (VR) systems means new methods of balance assessment are feasible in a clinical setting. This proof-of-concept study made use of the submillimeter tracking built into modern VR head-mounted displays (VRHMDs) to assess balance through the use of visual-vestibular conflict. The objective of this study was to evaluate the validity, acceptability, and reliability of using a VRHMD to assess balance in older adults. Validity was assessed by comparing measurements from the VRHMD to measurements of postural sway from a force plate. Acceptability was assessed through the use of the Simulator Sickness Questionnaire pre- and postexposure to assess possible side effects of the visual-vestibular conflict. Reliability was assessed by measuring correlations between repeated measurements 1 week apart. Variables of possible importance that were found to be reliable ( r ≥0.9) between tests separated by a week were then tested for differences compared to a control group. Assessment was performed as a cross-sectional single-site community center-based study in 13 older adults (≥65 years old, 80.2±7.3 years old, 77% female, five at risk of falls, eight controls). The VR balance assessment consisted of four modules: a baseline module, a reaction module, a balance module, and a seated assessment. There was a significant difference in the rate at which participants with a risk of falls changed their tilt in the anteroposterior direction compared to the control group. Participants with a risk of falls changed their tilt in the anteroposterior direction at 0.7°/second vs 0.4°/second for those without a history of falls. No significant differences were found between pre/postassessment for oculomotor score or total

Towards reducing impact-induced brain injury: lessons from a computational study of army and football helmet pads.

Science.gov (United States)

Moss, William C; King, Michael J; Blackman, Eric G

2014-01-01

We use computational simulations to compare the impact response of different football and U.S. Army helmet pad materials. We conduct experiments to characterise the material response of different helmet pads. We simulate experimental helmet impact tests performed by the U.S. Army to validate our methods. We then simulate a cylindrical impactor striking different pads. The acceleration history of the impactor is used to calculate the head injury criterion for each pad. We conduct sensitivity studies exploring the effects of pad composition, geometry and material stiffness. We find that (1) the football pad materials do not outperform the currently used military pad material in militarily relevant impact scenarios; (2) optimal material properties for a pad depend on impact energy and (3) thicker pads perform better at all velocities. Although we considered only the isolated response of pad materials, not entire helmet systems, our analysis suggests that by using larger helmet shells with correspondingly thicker pads, impact-induced traumatic brain injury may be reduced.

Applying the health action process approach to bicycle helmet use and evaluating a social marketing campaign.

Science.gov (United States)

Karl, Florian M; Smith, Jennifer; Piedt, Shannon; Turcotte, Kate; Pike, Ian

2017-08-05

Bicycle injuries are of concern in Canada. Since helmet use was mandated in 1996 in the province of British Columbia, Canada, use has increased and head injuries have decreased. Despite the law, many cyclists do not wear a helmet. Health action process approach (HAPA) model explains intention and behaviour with self-efficacy, risk perception, outcome expectancies and planning constructs. The present study examines the impact of a social marketing campaign on HAPA constructs in the context of bicycle helmet use. A questionnaire was administered to identify factors determining helmet use. Intention to obey the law, and perceived risk of being caught if not obeying the law were included as additional constructs. Path analysis was used to extract the strongest influences on intention and behaviour. The social marketing campaign was evaluated through t-test comparisons after propensity score matching and generalised linear modelling (GLM) were applied to adjust for the same covariates. 400 cyclists aged 25-54 years completed the questionnaire. Self-efficacy and Intention were most predictive of intention to wear a helmet, which, moderated by planning, strongly predicted behaviour. Perceived risk and outcome expectancies had no significant impact on intention. GLM showed that exposure to the campaign was significantly associated with higher values in self-efficacy, intention and bicycle helmet use. Self-efficacy and planning are important points of action for promoting helmet use. Social marketing campaigns that remind people of appropriate preventive action have an impact on behaviour. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Laminated helmet materials characterization by terahertz kinetics spectroscopy

Science.gov (United States)

Rahman, Anis; Rahman, Aunik K.

2015-05-01

High speed acquisition of reflected terahertz energy constitutes a kinetics spectrum that is an effective tool for layered materials' deformation characterization under ballistic impact. Here we describe utilizing the kinetics spectrum for quantifying a deformation event due to impact in material used for Soldier's helmet. The same technique may be utilized for real-time assessment of trauma by measuring the helmet wore by athletes. The deformation of a laminated material (e.g., a helmet) is dependent on the nature of impact and projectile; thus can uniquely characterize the impact condition leading to a diagnostic procedure based on the energy received by an athlete during an impact. We outline the calibration process for a given material under ballistic impact and then utilize the calibration for extracting physical parameters from the measured kinetics spectrum. Measured kinetics spectra are used to outline the method and rationale for extending the concept to a diagnosis tool. In particular, captured kinetics spectra from multilayered plates subjected to ballistic hit under experimental conditions by high speed digital acquisition system. An algorithm was devised to extract deformation and deformation velocity from which the energy received on the skull was estimated via laws of nonrelativistic motion. This energy is assumed to be related to actual injury conditions, thus forming a basis for determining whether the hit would cause concussion, trauma, or stigma. Such quantification may be used for diagnosing a Soldier's trauma condition in the field or that of an athlete's.

Modeling Of A Monocular, Full-Color, Laser-Scanning, Helmet-Mounted Display for Aviator Situational Awareness

Science.gov (United States)

2017-03-27

Army Aeromedical Research Laboratory P.O. Box 620577 Fort Rucker, AL 36362 USAARL 2017-10 Product Manager for Air Warrior SFAE-SDR-AW 6726 Odyssey Drive ...superimposed over real -world ambient scenes and artificial clutter. It is the idea of modeling HMDs to produce imagery that will in turn be...19 List of Figures 1. HMD Emission Spectra

Integrated Display & Environmental Awareness System

Data.gov (United States)

National Aeronautics and Space Administration — The goal of this project is the development of a head mounted display for use in operations here on Earth and in Space. The technology would provide various means of...

The formulation and implementation of a national helmet law: a case study from Viet Nam.

Science.gov (United States)

Passmore, Jonathon W; Nguyen, Lan Huong; Nguyen, Nam Phuong; Olivé, Jean-Marc

2010-10-01

Road traffic injuries are a leading cause of death and disability in Viet Nam. In 2008, official data reported 11 243 deaths and 7771 serious injuries on the roads, of which an estimated 60% of fatalities occur in motorcycle riders and passengers. In recognition of this problem, Viet Nam has had partial motorcycle helmet legislation since 1995. However, for a variety of reasons, implementation and enforcement have been limited. On 15 December 2007, Viet Nam's first comprehensive mandatory helmet law came into effect, covering all riders and passengers on all roads nationwide. Penalties increased ten-fold and cohorts of police were mobilized for enforcement. The Viet Nam national helmet legislation was developed and implemented by the National Traffic Safety Committee. Despite past barriers to enforcement, increased policing in 2008 led to 680 000 infringements being issued for non-helmet wearing. While changes in helmet wearing were not nationally observed, significant increases were documented in selected provinces in the first six months of the law's introduction. In Da Nang, helmet wearing increased from 27 to 99%. In the first three months after the law took effect, surveillance data from 20 urban and rural hospitals, found the risk of road traffic head injuries and deaths decreased by 16% and 18% respectively. Political leadership, intensive advanced public education and stringent enforcement have contributed to the successful implementation of the new law. Through continual monitoring of the legislation, loopholes detrimental to the effectiveness of the law have been identified and addressed.

Elevated Extravascular Lung Water Index (ELWI) as a Predictor of Failure of Continuous Positive Airway Pressure Via Helmet (Helmet-CPAP) in Patients With Acute Respiratory Failure After Major Surgery.

Science.gov (United States)

Redondo Calvo, Francisco Javier; Bejarano Ramirez, Natalia; Uña Orejon, Rafael; Villazala Garcia, Ruben; Yuste Peña, Ana Sofia; Belda, Francisco Javier

2015-11-01

NIV is increasingly used for prevention and treatment of respiratory complications and failure. Some of them are admitted to the PACU with advanced hemodynamic monitors which allow quantification of Extravascular Lung Water (EVLW) by transpulmonary thermodilution technique (TPTD) and Pulmonary Vascular Permeability (PVP) providing information on lung edema. The objective of this study was to ascertain if EVLW Index and PVP Index may predict failure (intubation) or success (non-intubation) in patients developing acute respiratory failure (ARF) in the postoperative period following major abdominal surgery, where the first line of treatment was non-invasive continuous positive airway pressure via a helmet. Hemodynamic variables, EVLWI and PVPI were monitored with a transpulmonary thermodilution hemodynamic monitor device (PiCCO™) before and after the application of CPAP. Avoidance of intubation was observed in 66% of patients with Helmet-CPAP. In these patients after the first hour of application of CPAP, PaO2/FiO2 ratio significantly increased (303.33±65.2 vs. 141.6±14.6, P<.01). Before starting Helmet-CPAP values of EVLWI and PVPI were significantly lower in non-intubated patients (EVLWI 8.6±1.08 vs. 11.8±0.99ml/kg IBW, P<.01 and PVPI 1.7±0.56 vs. 3.0±0.88, P<.01). An optimal cut-off value for EVLWI was established at 9.5, and at 2.45 for PVPI (sensitivity of 0.7; specificity of 0.9, P<.01). In this type of patient the physiological parameters that predict the failure of Helmet-CPAP with the greatest accuracy were the value of the EVLWI and PVPI before Helmet-CPAP institution and the PaO2/FiO2 ratio and the respiratory rate after one hour of CPAP. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

Brain response to primary blast wave using validated finite element models of human head and advanced combat helmet

Directory of Open Access Journals (Sweden)

Liying eZhang

2013-08-01

Full Text Available Blast-induced traumatic brain injury has emerged as a signature injury in combat casualty care. Present combat helmets are designed primarily to protect against ballistic and blunt impacts, but the current issue with helmets is protection concerning blasts. In order to delineate the blast wave attenuating capability of the Advanced Combat Helmet (ACH, a finite element (FE study was undertaken to evaluate the head response against blast loadings with and without helmet using a partially validated FE model of the human head and ACH. Four levels of overpressures (0.27-0.66 MPa from the Bowen’s lung iso-damage threshold curves were used to simulate blast insults. Effectiveness of the helmet with respect to head orientation was also investigated. The resulting biomechanical responses of the brain to blast threats were compared for human head with and without the helmet. For all Bowen’s cases, the peak intracranial pressures (ICP in the head ranged from 0.68-1.8 MPa in the coup cortical region. ACH was found to mitigate ICP in the head by 10-35%. Helmeted head resulted in 30% lower average peak brain strains and product of strain and strain rate. Among three blast loading directions with ACH, highest reduction in peak ICP (44% was due to backward blasts whereas the lowest reduction in peak ICP and brain strains was due to forward blast (27%. The biomechanical responses of a human head to primary blast insult exhibited directional sensitivity owing to the different geometry contours and coverage of the helmet construction and asymmetric anatomy of the head. Thus, direction-specific tolerances are needed in helmet design in order to offer omni-directional protection for the human head. The blasts of varying peak overpressures and durations that are believed to produce the same level of lung injury produce different levels of mechanical responses in the brain, and hence "iso-damage" curves for brain injury are likely different than the Bowen curves

Impact of Helmet Use on Severity of Epidural Hematomas in Cambodia.

Science.gov (United States)

Gupta, Saksham; Iv, Vycheth; Sam, Nang; Vuthy, Din; Klaric, Katherine; Shrime, Mark G; Park, Kee B

2017-04-01

Traumatic brain injury is a major cause of morbidity and mortality worldwide, often necessitating neurosurgical intervention to evacuate intracranial bleeding. Since the early 2000s, Cambodia has been undergoing a rapid increase in motorcycle transit and in road traffic accidents, but the prevalence of helmet usage remains low. Epidural hematomas are severe traumatic brain injuries that can necessitate neurosurgical intervention. This is a retrospective cohort study of patients with epidural hematoma secondary to motorcycle accidents who presented to a major national tertiary care center in Phnom Penh, Cambodia, between November 2013 and March 2016. All patients were diagnosed with computed tomography of the head. In this cohort, 21.6% of patients in motorcycle accidents presented with epidural hematoma and 89.1% of patients were men, 47.6% were intoxicated, and were 87.8% were not wearing helmets at the moment of impact. Not wearing a helmet was associated with a 6.90-fold increase in odds of presenting with a moderate-to-severe Glasgow coma scale score and a 3.76-fold increase in odds of requiring craniotomy or craniectomy for evacuation of hematoma. Male sex was also associated with increased odds of higher clinical severity at presentation and indication for craniotomy or craniectomy, and alcohol intoxication at the time of accident was not associated with either. Helmet usage is protective in reducing the severity of presentation and need for neurosurgical intervention for patients with epidural hematoma secondary to motorcycle accidents. Copyright © 2016 Elsevier Inc. All rights reserved.

The physiological demands of horseback mustering when wearing an equestrian helmet.

Science.gov (United States)

Taylor, Nigel A S; Caldwell, Joanne N; Dyer, Rodd

2008-09-01

The hottest months on northern Australian cattle stations are from September to November, and it is during these months that horseback cattle mustering occurs. Stockmen wear clothing that restricts heat loss, and protective helmets have recently been introduced. Anecdotal evidence points to the possibility that helmets may increase the probability of developing heat illness, or reducing workplace performance. In this project, we quantified the working (thermal) environment on such cattle stations, and measured the metabolic demands on, and concurrent physiological strain in stockmen during mustering, whilst wearing an equestrian helmet. During horseback work, the average heart rate was 102.0 beats min(-1) (SD 14.0), with almost 90% of the time (238 min) spent working at intensities <50% of the heart rate reserve. The projected metabolic heat production during mustering ranged between 178 and 333 W (women), and between 212 and 542 W (men). The average core temperature was 37.6 degrees C, while the mean skin temperature averaged 34.1 degrees C. It was concluded that the working environment is, on average, thermally uncompensable during the mustering season. However, horseback mustering per se is a relatively low-intensity activity, interspersed with short periods of high-intensity work. This activity level was reflected within core temperatures, which rarely climbed above values associated with light-moderate exercise. Thus, whilst the climatic state was uncompensable, stockmen used behavioural strategies to minimise the risk of heat illness. Finally, it was observed that the helmet, though unpleasant to wear, did not appear to increase thermal strain in a manner that would disadvantage stockmen.

Circular displays: control/display arrangements and stereotype strength with eight different display locations.

Science.gov (United States)

Chan, Alan H S; Hoffmann, Errol R

2015-01-01

Two experiments are reported that were designed to investigate control/display arrangements having high stereotype strengths when using circular displays. Eight display locations relative to the operator and control were tested with rotational and translational controls situated on different planes according to the Frame of Reference Transformation Tool (FORT) model of Wickens et al. (2010). (Left. No, Right! Development of the Frame of Reference Transformation Tool (FORT), Proceedings of the Human Factors and Ergonomics Society 54th Annual Meeting, 54: 1022-1026). In many cases, there was little effect of display locations, indicating the importance of the Worringham and Beringer (1998. Directional stimulus-response compatibility: a test of three alternative principles. Ergonomics, 41(6), 864-880) Visual Field principle and an extension of this principle for rotary controls (Hoffmann and Chan (2013). The Worringham and Beringer 'visual field' principle for rotary controls. Ergonomics, 56(10), 1620-1624). The initial indicator position (12, 3, 6 and 9 o'clock) had a major effect on control/display stereotype strength for many of the six controls tested. Best display/control arrangements are listed for each of the different control types (rotational and translational) and for the planes on which they are mounted. Data have application where a circular display is used due to limited display panel space and applies to space-craft, robotics operators, hospital equipment and home appliances. Practitioner Summary: Circular displays are often used when there is limited space available on a control panel. Display/control arrangements having high stereotype strength are listed for four initial indicator positions. These arrangements are best for design purposes.

The burden of motorcycle-related neuro-trauma in Ireland and associated helmet usage.

LENUS (Irish Health Repository)

Murphy, R K J

2009-04-01

Motorcycles represent less than 2% of the licensed vehicles but motorcyclists account for 12% of road deaths in Ireland. The British Road Safety Authority has introduced the Sharp programme, which hopes to save 50 lives in the U.K. each year alone by helping riders to choose the best-fitting and safest helmets. We evaluated the pattern of head injuries sustained by motorcyclists referred to the two neurosurgical centres Beaumont Hospital and Cork University Hospital in Ireland and ascertained if the new SHARP guidelines could be of benefit in reducing the burden of motorcycle related neurotrauma and disability in Ireland. Despite Ireland having mandatory helmet laws almost a quarter of our motorcyclists with traumatic brain injury were unhelmeted. A significant reduction in mortality and morbidity is predicted if all motorcyclists in Ireland were to wear helmets that satisfied the SHARP criteria.

Self-Powered Safety Helmet Based on Hybridized Nanogenerator for Emergency.

Science.gov (United States)

Jin, Long; Chen, Jun; Zhang, Binbin; Deng, Weili; Zhang, Lei; Zhang, Haitao; Huang, Xi; Zhu, Minhao; Yang, Weiqing; Wang, Zhong Lin

2016-08-23

The rapid development of Internet of Things and the related sensor technology requires sustainable power sources for their continuous operation. Scavenging and utilizing the ambient environmental energy could be a superior solution. Here, we report a self-powered helmet for emergency, which was powered by the energy converted from ambient mechanical vibration via a hybridized nanogenerator that consists of a triboelectric nanogenerator (TENG) and an electromagnetic generator (EMG). Integrating with transformers and rectifiers, the hybridized nanogenerator can deliver a power density up to 167.22 W/m(3), which was demonstrated to light up 1000 commercial light-emitting diodes (LEDs) instantaneously. By wearing the developed safety helmet, equipped with rationally designed hybridized nanogenerator, the harvested vibration energy from natural human motion is also capable of powering a wireless pedometer for real-time transmitting data reporting to a personal cell phone. Without adding much extra weight to a commercial one, the developed wearing helmet can be a superior sustainable power source for explorers, engineers, mine-workers under well, as well as and disaster-relief workers, especially in remote areas. This work not only presents a significant step toward energy harvesting from human biomechanical movement, but also greatly expands the applicability of TENGs as power sources for self-sustained electronics.

Continuous positive airway pressure with helmet versus mask in infants with bronchiolitis: an RCT.

Science.gov (United States)

Chidini, Giovanna; Piastra, Marco; Marchesi, Tiziana; De Luca, Daniele; Napolitano, Luisa; Salvo, Ida; Wolfler, Andrea; Pelosi, Paolo; Damasco, Mirco; Conti, Giorgio; Calderini, Edoardo

2015-04-01

Noninvasive continuous positive airway pressure (CPAP) is usually applied with a nasal or facial mask to treat mild acute respiratory failure (ARF) in infants. A pediatric helmet has now been introduced in clinical practice to deliver CPAP. This study compared treatment failure rates during CPAP delivered by helmet or facial mask in infants with respiratory syncytial virus-induced ARF. In this multicenter randomized controlled trial, 30 infants with respiratory syncytial virus-induced ARF were randomized to receive CPAP by helmet (n = 17) or facial mask (n = 13). The primary endpoint was treatment failure rate (defined as due to intolerance or need for intubation). Secondary outcomes were CPAP application time, number of patients requiring sedation, and complications with each interface. Compared with the facial mask, CPAP by helmet had a lower treatment failure rate due to intolerance (3/17 [17%] vs 7/13 [54%], P = .009), and fewer infants required sedation (6/17 [35%] vs 13/13 [100%], P = .023); the intubation rates were similar. In successfully treated patients, CPAP resulted in better gas exchange and breathing pattern with both interfaces. No major complications due to the interfaces occurred, but CPAP by mask had higher rates of cutaneous sores and leaks. These findings confirm that CPAP delivered by helmet is better tolerated than CPAP delivered by facial mask and requires less sedation. In addition, it is safe to use and free from adverse events, even in a prolonged clinical setting. Copyright © 2015 by the American Academy of Pediatrics.

The Ability of American Football Helmets to Manage Linear Acceleration With Repeated High-Energy Impacts.

Science.gov (United States)

Cournoyer, Janie; Post, Andrew; Rousseau, Philippe; Hoshizaki, Blaine

2016-03-01

Football players can receive up to 1400 head impacts per season, averaging 6.3 impacts per practice and 14.3 impacts per game. A decrease in the capacity of a helmet to manage linear acceleration with multiple impacts could increase the risk of traumatic brain injury. To investigate the ability of football helmets to manage linear acceleration with multiple high-energy impacts. Descriptive laboratory study. Laboratory. We collected linear-acceleration data for 100 impacts at 6 locations on 4 helmets of different models currently used in football. Impacts 11 to 20 were compared with impacts 91 to 100 for each of the 6 locations. Linear acceleration was greater after multiple impacts (91-100) than after the first few impacts (11-20) for the front, front-boss, rear, and top locations. However, these differences are not clinically relevant as they do not affect the risk for head injury. American football helmet performance deteriorated with multiple impacts, but this is unlikely to be a factor in head-injury causation during a game or over a season.

The Cyclists Helmet Study in Juba, Southern Sudan, 2006

African Journals Online (AJOL)

Ann Burgess

Juba has a poor road network and few public transport options, with an increasing number of people riding ... The conclusion is that cyclists need information on the importance of wearing a helmet. ... Leading safety advocates recommend the.

A comparison of head-mounted and hand-held displays for 360° videos with focus on attitude and behavior change

DEFF Research Database (Denmark)

Fonseca, Diana; Kraus, Martin

2016-01-01

The present study is designed to test how immersion, presence, and narrative content (with a focus on emotional immersion) can affect one's pro-environmental attitude and behavior with specific interest in 360° videos and meat consumption as a non pro-environmental behavior. This research describes...... a between-group design experiment that compares two systems with different levels of immersion and two types of narratives, one with and one without emotional content. In the immersive video (IV) condition (high immersion), 21 participants used a Head-Mounted Display (HMD) to watch an emotional 360° video...... about meat consumption and its effects on the environment; another 21 participants experienced the tablet condition (low immersion) where they viewed the same video but with a 10.1 inch tablet; 22 participants in the control condition viewed a non emotional video about submarines with an HMD...

Structural Equation Modelling in Behavioral Intention to Use Safety Helmet Reminder System

Directory of Open Access Journals (Sweden)

Rosli Naida

2016-01-01

Full Text Available Motorcycle is one of private transportation which has been widely used in many countries including Malaysia. However, motorcycles are the most dangerous form of motorized transport. Royal Malaysian Police (PDRM statistics recorded that motorcycle is the highest vehicle (45.9% involved in traffic accident compared to other vehicles. The potential cause of the death to the motorcyclist was due to the head injury. One of strategy to mitigate this problem is through proper usage of safety helmet. Therefore, this paper was introduce a new approach on motorcyclist safety by using the Technology Acceptance Model (TAM with additional determinants that contribute to behavioral intention and to increase the proper usage of safety helmets among Malaysian motorcyclists. The Structural Equation Modelling (SEM was used to test the structural TAM proposed. The evaluation for structural model showed the goodness of fit indices are excellent fit. This study found that perceived ease of use, perceived usefulness and social norm are significant towards behavioral intention to use Safety Helmet Reminder System (SHR.

The protective effect of helmet use in motorcycle and bicycle accidents: a propensity score-matched study based on a trauma registry system.

Science.gov (United States)

Kuo, Spencer C H; Kuo, Pao-Jen; Rau, Cheng-Shyuan; Chen, Yi-Chun; Hsieh, Hsiao-Yun; Hsieh, Ching-Hua

2017-08-07

Transportation by motorcycle and bicycle has become popular in Taiwan, this study was designed to investigate the protective effect of helmet use during motorcycle and bicycle accidents by using a propensity score-matched study based on trauma registry system data. Data of adult patients hospitalized for motorcycle or bicycle accidents between January 1, 2009 and December 31, 2015 were retrieved from the Trauma Registry System. These included 7735 motorcyclists with helmet use, 863 motorcyclists without helmet use, 76 bicyclists with helmet use, and 647 bicyclists without helmet use. The primary outcome measurement was in-hospital mortality. Secondary outcomes were the hospital length of stay (LOS), intensive care unit (ICU) admission rate, and ICU LOS. Normally distributed continuous data were analyzed by the unpaired Student t-test, and non-normally distributed data were compared using the Mann-Whitney U-test. Two-sided Fisher exact or Pearson chi-square tests were used to compare categorical data. Propensity score matching (1:1 ratio using optimal method with a 0.2 caliper width) was performed using NCSS software, adjusting for the following covariates: sex, age, and comorbidities. Further logistic regression was used to evaluate the effect of helmet use on mortality rates of motorcyclists and bicyclists, respectively. The mortality rate for motorcyclists with helmet use (1.1%) was significantly lower than for motorcyclists without helmet use (4.2%; odds ratio [OR] 0.2; 95% confidence interval [CI]: 0.17-0.37; p Motorcycle helmets provide protection to adult motorcyclists involved in traffic accidents and their use is associated with a decrease in mortality rates and the risk of head injuries. However, no such protective effect of helmet use was observed for bicyclists involved in collisions.

Effect of Filters on the Noise Generated by Continuous Positive Airway Pressure Delivered via a Helmet

Directory of Open Access Journals (Sweden)

Ricardo Hernández-Molina

2017-01-01

Full Text Available Introduction: One of the problems that the delivery of continuous positive airway pressure (CPAP via a helmet poses is the generation of noise. The objective of our study was to assess the effect that the use of filter has on sound pressure levels generated by the delivery of positive airway pressure at different gas flow rates. Materials and Methods: Sound pressure levels generated by neonatal helmet CPAP delivery were measured at different gas flows (20, 30, and 40 l/min with and without a breathing filter. Noise intensity was measured by installing microphones in the inner ear of dummy heads wearing helmets. Results: The sound pressure level increased by 38% at a gas flow of 40 l/min, as compared to a gas flow of 20 l/min {74 dBA [interquartile range (IQR 2,2] vs 52 dBA (IQR 5,9, respectively}. Using the breathing filter as a diffuser has a variety of effects on sound pressure levels according to the gas flow rate. Conclusion: The intensity of the noise generated by helmet delivery of positive airway pressure depends on the type of helmet used, gas flow, and use or not of a diffuser filter. Breathing filters with gas flows over 30 l/min might not be recommended since they would not attenuate but will rather amplify sound pressure.

Color speckle in laser displays

Science.gov (United States)

Kuroda, Kazuo

2015-07-01

At the beginning of this century, lighting technology has been shifted from discharge lamps, fluorescent lamps and electric bulbs to solid-state lighting. Current solid-state lighting is based on the light emitting diodes (LED) technology, but the laser lighting technology is developing rapidly, such as, laser cinema projectors, laser TVs, laser head-up displays, laser head mounted displays, and laser headlamps for motor vehicles. One of the main issues of laser displays is the reduction of speckle noise1). For the monochromatic laser light, speckle is random interference pattern on the image plane (retina for human observer). For laser displays, RGB (red-green-blue) lasers form speckle patterns independently, which results in random distribution of chromaticity, called color speckle2).

Manufacture and impact analysis of bmx helmet made from polymeric foam composite strengthened by oil palm empty fruit bunch fiber

Science.gov (United States)

Mahadi

2018-02-01

Helmets are protective head gears wear by bicycle riders for protection against injury in case of the accident. Helmet standards require helmets to be tested with a simple drop test onto an anvil. The purpose of research is to know toughness of bicycle helmet made from polymeric foam composite strengthened by oil palm empty fruit bunch fiber. This research contains report result manufacture and impacts analysis of bicycle helmet made from polymeric foam composite materials strengthened by oil palm empty fruit bunch fiber (EFB). The geometric helmet structure consists of shell and liner; both layers have sandwich structure. The shell uses matrix unsaturated Polyester BQTN-157EX material, chopped strand mat 300 glass fiber reinforce and methyl ethyl ketone peroxide (MEKPO) catalyst with the weight composition of 100 gr, 15 gr, and 5 gr. The liner uses matrix unsaturated Polyester BQTN-157 EX material, EFB fiber reinforces, Polyurethane blowing agent, and MEKPO catalyst with the composition of 275 gr (50%), 27.5 gr (5%), 247 gr (45%), and 27.5 gr (5%). Layers of the helmet made by using hand lay-up method and gravity casting method. Mechanical properties of polymeric foam were the tensile strength (ơt) 1.17 Mpa, compressive strength (ơc) 0.51 MPa, bending strength (ơb) 3.94 MPa, elasticity modulus (E) 37.97 Mpa, density (ρ) 193 (kg/m3). M4A model helmet is the most ergonomic with the thickness 10 mm and the amount of air channel 11. Free fall impact test was done in 9 samples with the thickness of 10 mm with the height of 1.5 m. The result of the impact test was impacted force (Fi) 241.55 N, Impulse (I) 6.28 Ns, impact Strength (ơi) 2.02 Mpa and impact Energy (Ei) 283.77 Joule. The properties of bicycle helmet model BMX-M4A type was 264 mm length, 184 mm width, 154 mm height, 10 mm thick, 580 mm head circle, 331 g mass and 11 wind channels.

Simulation study comparing the helmet-chin PET with a cylindrical PET of the same number of detectors

Science.gov (United States)

Ahmed, Abdella M.; Tashima, Hideaki; Yoshida, Eiji; Nishikido, Fumihiko; Yamaya, Taiga

2017-06-01

There is a growing interest in developing brain PET scanners with high sensitivity and high spatial resolution for early diagnosis of neurodegenerative diseases and studies of brain functions. Sensitivity of the PET scanner can be improved by increasing the solid angle. However, conventional PET scanners are designed based on a cylindrical geometry, which may not be the most efficient design for brain imaging in terms of the balance between sensitivity and cost. We proposed a dedicated brain PET scanner based on a hemispheric shape detector and a chin detector (referred to as the helmet-chin PET), which is designed to maximize the solid angle by increasing the number of lines-of-response in the hemisphere. The parallax error, which PET scanners with a large solid angle tend to have, can be suppressed by the use of depth-of-interaction detectors. In this study, we carry out a realistic evaluation of the helmet-chin PET using Monte Carlo simulation based on the 4-layer GSO detector which consists of a 16  ×  16  ×  4 array of crystals with dimensions of 2.8  ×  2.8  ×  7.5 mm3. The purpose of this simulation is to show the gain in imaging performance of the helmet-chin PET compared with the cylindrical PET using the same number of detectors in each configuration. The sensitivity of the helmet-chin PET evaluated with a cylindrical phantom has a significant increase, especially at the top of the (field-of-view) FOV. The peak-NECR of the helmet-chin PET is 1.4 times higher compared to the cylindrical PET. The helmet-chin PET provides relatively low noise images throughout the FOV compared to the cylindrical PET which exhibits enhanced noise at the peripheral regions. The results show the helmet-chin PET can significantly improve the sensitivity and reduce the noise in the reconstructed images.

Sir Hugh Cairns: The neurosurgeon who introduced crash helmets

Directory of Open Access Journals (Sweden)

Shahsivadhanan Sundaravadhanan

2017-01-01

Full Text Available Statistics prove that more Indians die in Road traffic related accidents than in wars. Prior to World War II, the death toll across the world used to be very high. It was at this juncture that a Military Neurosurgeon named Hugh Cairns introduced the compulsory wearing of crash helmets and brought about a reduction in mortality by more than 50%. Within a decade of introduction of crash helmets in Britain, the entire world followed suit. The results of his efforts are here for all of us to see. This innovative military neurosurgeon is credited as the one who introduced the concept of mobile neurosurgical units during world war and also the first proponent of usage of penicillin in war. His concepts in war surgery are still followed by militaries across the world. This article comes as a tribute to this great Neurosurgeon who helped in saving millions of lives.

Outcome analysis after helmet therapy using 3D photogrammetry in patients with deformational plagiocephaly: the role of root mean square.

Science.gov (United States)

Moghaddam, Mahsa Bidgoli; Brown, Trevor M; Clausen, April; DaSilva, Trevor; Ho, Emily; Forrest, Christopher R

2014-02-01

Deformational plagiocephaly (DP) is a multifactorial non-synostotic cranial deformity with a reported incidence as high as 1 in 7 infants in North America. Treatment options have focused on non-operative interventions including head repositioning and the use of an orthotic helmet device. Previous studies have used linear and two dimensional outcome measures to assess changes in cranial symmetry after helmet therapy. Our objective was to demonstrate improvement in head shape after treatment with a cranial molding helmet by using Root Mean Square (RMS), a measure unique to 3D photogrammetry, which takes into account both changes in volume and shape over time. Three dimensional photographs were obtained before and after molding helmet treatment in 40 infants (4-10 months old) with deformational plagiocephaly. Anatomical reference planes and measurements were recorded using the 3dMD Vultus(®) analysis software. RMS was used to quantify symmetry by superimposing left and right quadrants and calculating the mean value of aggregate distances between surfaces. Over 95% of the patients demonstrated an improvement in symmetry with helmet therapy. Furthermore, when the sample of infants was divided into two treatment subgroups, a statistically significant correlation was found between the age at the beginning of treatment and the change in the RMS value. When helmet therapy was started before 7 months of age a greater improvement in symmetry was seen. This work represents application of the technique of RMS analysis to demonstrate the efficacy of treatment of deformational plagiocephaly with a cranial molding helmet. Copyright © 2014. Published by Elsevier Ltd.

Recognition of American Sign Language (ASL) Classifiers in a Planetarium Using a Head-Mounted Display

Science.gov (United States)

Hintz, Eric G.; Jones, Michael; Lawler, Jeannette; Bench, Nathan

2015-01-01

A traditional accommodation for the deaf or hard-of-hearing in a planetarium show is some type of captioning system or a signer on the floor. Both of these have significant drawbacks given the nature of a planetarium show. Young audience members who are deaf likely don't have the reading skills needed to make a captioning system effective. A signer on the floor requires light which can then splash onto the dome. We have examined the potential of using a Head-Mounted Display (HMD) to provide an American Sign Language (ASL) translation. Our preliminary test used a canned planetarium show with a pre-recorded sound track. Since many astronomical objects don't have official ASL signs, the signer had to use classifiers to describe the different objects. Since these are not official signs, these classifiers provided a way to test to see if students were picking up the information using the HMD.We will present results that demonstrate that the use of HMDs is at least as effective as projecting a signer on the dome. This also showed that the HMD could provide the necessary accommodation for students for whom captioning was ineffective. We will also discuss the current effort to provide a live signer without the light splash effect and our early results on teaching effectiveness with HMDs.This work is partially supported by funding from the National Science Foundation grant IIS-1124548 and the Sorenson Foundation.

Randomized Comparison of Helmet CPAP Versus High-Flow Nasal Cannula Oxygen in Pediatric Respiratory Distress.

Science.gov (United States)

Vitaliti, Giovanna; Vitaliti, Maria Concetta; Finocchiaro, Maria Carla; Di Stefano, Vita Antonella; Pavone, Piero; Matin, Nassim; Motamed-Gorji, Nazgol; Lubrano, Riccardo; Falsaperla, Raffaele

2017-08-01

The current study aimed to compare the efficacy and safety of 2 noninvasive respiratory support methods, which included helmet CPAP and high-flow nasal cannula (HFNC) in children with respiratory distress admitted to a pediatric intermediate care unit. This study was a prospective observational study conducted on children with respiratory distress (age 1-24 months) who were admitted to our acute and emergency operative unit. All included subjects were randomly treated with helmet CPAP or HFNC in a 1:1 fashion until their clinical picture, oxygen saturation, and arterial blood gas (ABG) parameters resolved. The efficiencies of helmet CPAP and HFNC were evaluated by breathing frequency, S pO 2 , ABG pH, ABG P aCO 2 , ABG P aO 2 , and P aO 2 /F IO 2 , recorded once at baseline and then after 1 and 6 h of treatment. Both noninvasive respiratory support modalities were compared with a control group of subjects with respiratory distress under standard therapeutic pharmaceutical protocols. We found that both helmet CPAP and HFNC were efficient in improving the clinical conditions of subjects with mild-to-moderate respiratory distress, although clinical response to helmet CPAP was more efficient and rapid compared with HFNC. Children who received respiratory support had a better clinical course in terms of hospitalization, days of intravenous rehydration therapy, and days of drug administration compared with the control group ( P CPAP and HFNC in respiratory distress resolution in a pediatric intermediate care setting. It aims to identify the most efficient treatment to avoid pediatric ICU admissions and endotracheal intubation and reduce the administration of drugs and days of hospitalization. Copyright © 2017 by Daedalus Enterprises.

Concussion Characteristics in High School Football by Helmet Age/Recondition Status, Manufacturer, and Model: 2008-2009 Through 2012-2013 Academic Years in the United States.

Science.gov (United States)

Collins, Christy L; McKenzie, Lara B; Ferketich, Amy K; Andridge, Rebecca; Xiang, Huiyun; Comstock, R Dawn

2016-06-01

Football helmets used by high school athletes in the United States should meet the National Operating Committee on Standards for Athletic Equipment performance standards. Despite differences in interior padding and exterior shells, all football helmets should provide comparable protection against concussions. Yet, debate continues on whether differences in the rates or severity of concussions exist based on helmet age/recondition status, manufacturer, or model. To investigate whether high school football concussion characteristics varied by helmet age/recondition status, manufacturer, and model. Descriptive epidemiological study. High school football concussion and helmet data were collected from academic years 2008-2009 through 2012-2013 as part of the National High School Sports-Related Injury Surveillance Study. The certified athletic trainers of participating schools submitted athlete-exposure (AE) and injury information weekly. Participating schools reported 2900 football concussions during 3,528,790 AEs for an overall rate of 8.2 concussions per 10,000 AEs. Concussion rates significantly increased from 2008-2009 through 2012-2013 overall (P = .006) as well as in competition (P = .027) and practice (P = .023). Characteristics of concussed football players (ie, mean number of symptoms, specific concussion symptoms, symptom resolution time, and time until return to play) were similar among players wearing new helmets when compared with reconditioned helmets. Fewer players wearing an old/not reconditioned helmet had concussion symptoms resolve within 1 day compared with players wearing a new helmet. Despite differences in the manufacturers and models of helmets worn by all high school football players compared with players who sustained a concussion, the mean number of concussion symptoms, specific concussion symptoms, symptom resolution time, and time until return to play were similar for concussions sustained by football players wearing the most common helmet

Defining Constellation Suit Helmet Field of View Requirements Employing a Mission Segment Based Reduction Process

Science.gov (United States)

McFarland, Shane

2009-01-01

Field of view has always been a design feature paramount to helmets, and in particular space suits, where the helmet must provide an adequate field of view for a large range of activities, environments, and body positions. For Project Constellation, a different approach to helmet requirement maturation was utilized; one that was less a direct function of body position and suit pressure and more a function of the mission segment in which the field of view will be required. Through taxonimization of various parameters that affect suited field of view, as well as consideration for possible nominal and contingency operations during that mission segment, a reduction process was employed to condense the large number of possible outcomes to only six unique field of view angle requirements that still captured all necessary variables while sacrificing minimal fidelity.

COMPARISON OF A HEAD MOUNTED IMPACT MEASUREMENT DEVICE TO THE HYBRID III ANTHROPOMORPHIC TESTING DEVICE IN A CONTROLLED LABORATORY SETTING.

Science.gov (United States)

Schussler, Eric; Stark, David; Bolte, John H; Kang, Yun Seok; Onate, James A

2017-08-01

Reports estimate that 1.6 to 3.8 million cases of concussion occur in sports and recreation each year in the United States. Despite continued efforts to reduce the occurrence of concussion, the rate of diagnosis continues to increase. The mechanisms of concussion are thought to involve linear and rotational head accelerations and velocities. One method of quantifying the kinematics experienced during sport participation is to place measurement devices into the athlete's helmet or directly on the athlete's head. The purpose of this research to determine the accuracy of a head mounted device for measuring the head accelerations experienced by the wearer. This will be accomplished by identifying the error in Peak Linear Acceleration (PLA), Peak Rotational Acceleration (PRA) and Peak Rotational Velocity (PRV) of the device. Laboratory study. A helmeted Hybrid III 50th percentile male headform was impacted via a pneumatic ram from the front, side, rear, front oblique and rear oblique at speeds from 1.5 to 5 m/s. The X2 Biosystems xPatch® (Seattle, WA) sensor was placed on the headform's right side at the approximate location of the mastoid process. Measures of PLA, PRA, PRV from the xPatch ® and Hybrid III were analyzed for Root Mean Square Error (RMSE), and Absolute and Relative Error (AE, RE). Seventy-six impacts were analyzed. All measures of correlation, fixed through the origin, were found to be strong: PLA R 2 =0.967 pstandard yet above the average error of testing devices in both PLA and PRA, but a low error in PRV. PLA measures from the xPatch® system demonstrated a high level of correlation with the PLA data from the Hybrid III mounted data collection system. 3.

A green-color portable waveguide eyewear display system

Science.gov (United States)

Xia, Lingbo; Xu, Ke; Wu, Zhengming; Hu, Yingtian; Li, Zhenzhen; Wang, Yongtian; Liu, Juan

2013-08-01

Waveguide display systems are widely used in various display fields, especially in head mounted display. Comparing with the traditional head mounted display system, this device dramatically reduce the size and mass. However, there are still several fatal problems such as high scatting, the cumbersome design and chromatic aberration that should be solved. We designed and fabricated a monochromatic portable eyewear display system consist of a comfortable eyewear device and waveguide system with two holographic gratings located on the substrate symmetrically. We record the gratings on the photopolymer medium with high efficiency and wavelength sensitivity. The light emitting from the micro-display is diffracted by the grating and trapped in the glass substrate by total internal reflection. The relationship between the diffraction efficiency and exposure value is studied and analyzed, and we fabricated the gratings with appropriate diffraction efficiency in a optimization condition. To avoid the disturbance of the stray light, we optimize the waveguide system numerically and perform the optical experiments. With this system, people can both see through the waveguide to obtain the information outside and catch the information from the micro display. After considering the human body engineering and industrial production, we design the structure in a compact and portable way. It has the advantage of small-type configuration and economic acceptable. It is believe that this kind of planar waveguide system is a potentially replaceable choice for the portable devices in future mobile communications.

A redesign of OGC Symbology Encoding standard for sharing cartography

Directory of Open Access Journals (Sweden)

Erwan Bocher

2018-01-01

Full Text Available Despite most Spatial Data Infrastructures offering service-based visualization of geospatial data, requirements are often at a very basic level leading to poor quality of maps. This is a general observation for any geospatial architecture as soon as open standards as those of the Open Geospatial Consortium (OGC are applied. To improve the situation, this paper does focus on improvements at the portrayal interoperability side by considering standardization aspects. We propose two major redesign recommendations. First to consolidate the cartographic theory at the core of the OGC Symbology Encoding standard. Secondly to build the standard in a modular way so as to be ready to be extended with upcoming future cartographic requirements. Thus, we start by defining portrayal interoperability by means of typical-use cases that frame the concept of sharing cartography. Then we bring to light the strengths and limits of the relevant open standards to consider in this context. Finally we propose a set of recommendations to overcome the limits so as to make these use cases a true reality. Even if the definition of a cartographic-oriented standard is not able to act as a complete cartographic design framework by itself, we argue that pushing forward the standardization work dedicated to cartography is a way to share and disseminate good practices and finally to improve the quality of the visualizations.

An Analysis of Technology-Related Distracted Biking Behaviors and Helmet Use Among Cyclists in New York City.

Science.gov (United States)

Ethan, Danna; Basch, Corey H; Johnson, Glen D; Hammond, Rodney; Chow, Ching Man; Varsos, Victoria

2016-02-01

Bicycling is becoming an increasingly utilized mode of transportation in New York City. Technology-related distracted bicycling and helmet use are behaviors that can impact bike safety. The aims of this study were twofold: (1) to determine rates and types of technology-related distracted behaviors among bicyclists in the borough of Manhattan in New York City; and (2) to assess the rate of bicycle helmet use among these cyclists. Bicyclists in five popular riding areas in Manhattan were observed for a total of 50 h using a digital video camera during summer months in 2014. Videos were coded and enumerated for the total number and gender of cyclists, type of bicycle, number wearing headphones/earbuds and/or using a mobile phone, and whether the cyclist was wearing a helmet. Almost 25,000 cyclists were observed across the five selected locations (n = 24,861). Riders were almost four times more likely not to wear a helmet on rental bikes as compared with non-rentals (Citi Bike(®) OR 3.8; 95% CI 2.5, 5.9: other rental OR 3.8; 95% CI 3.0, 4.9). Significantly increased odds of not wearing a helmet were observed for females relative to males (OR 1.4; 95% CI 1.1, 1.8) across varied times and locations. Overall, rates of technology-related distraction were low, with headphone use being most prevalent. Males were more likely to wear headphones/earbuds (OR 2.0; 95% CI 1.4, 2.9), as were cyclists on Citi Bikes relative to other rental bikes (OR 2.2; 95% CI 1.3, 3.6). Findings from this study contribute to the growing literature on distracted biking and helmet use among bike share program riders and other cyclists and can inform policymakers and program planners aiming to improve bicycle safety in urban settings.

Further Analysis of Motorcycle Helmet Effectiveness Using CODES Linked Data

Science.gov (United States)

1998-01-01

Linked data from the Crash Outcome Data Evaluation System (CODES) in seven : states was used by the National Highway Traffic Safety Administration as the : basis of a 1996 Report to Congress on the Benefits of Safety Belts and : Motorcycle Helmets (D...

Performance and ergonomic characteristics of expert surgeons using a face-mounted display during virtual reality-simulated laparoscopic surgery: an electromyographically based study.

Science.gov (United States)

Lin, D W; Bush, R W; Earle, D B; Seymour, N E

2007-07-01

Display positions for laparoscopy in current operating rooms may not be optimal for surgeon comfort or task performance, and face-mounted displays (FMDs) have been forwarded as a potential ergonomic solution. Little is known concerning expert use characteristics of these devices that might help define their role in future surgical care. The authors report the performance and ergonomic characterization of an FMD using virtual reality simulation technology to recreate the surgical environment. An FMD was studied in short- and long-duration trials of validated virtual reality-simulated surgical tasks. For the short-duration phase 7, expert surgeons were familiarized with a task on a conventional monitor, then returned on two separate occasions to repeat the task with the FMD while digital photos were taken during task performance and at the end in a standardized fashion. For the long-duration phase 5, expert surgeons performed two separate trials with repetitive groups of validated tasks for a minimum of 30 min while electromyelogram and performance data were measured. Photos of their gaze angle during and at the end of the trial were taken. All the participants consistently assumed a gaze angle slightly below horizontal during task performance. Performance scores on the FMD did not differ from those obtained with a conventional display, and remained stable with repetitive task performance. No participant had electromyelogram signals that exceeded the established thresholds for fatigue, but some had values within the threshold range. The natural gaze angle during simulated surgery was consistently a bit below horizontal during rigorous virtual reality-simulated tasks. Performance was not compromised during expert surgeons' use of an FMD, nor did muscle fatigue characteristics arise under these conditions. The findings suggest that these devices may represent a viable alternative to conventional displays for minimally invasive surgery, but definition of specific roles

SYMPATHETIC FILAMENT ERUPTIONS FROM A BIPOLAR HELMET STREAMER IN THE SUN

International Nuclear Information System (INIS)

Yang Jiayan; Jiang Yunchun; Zheng Ruisheng; Bi Yi; Hong Junchao; Yang Bo

2012-01-01

On 2005 August 5, two solar filaments erupted successively from different confined arcades underlying a common overarching multiple-arcade bipolar helmet streamer. We present detailed observations of these two events and identify them as sympathetic filament eruptions. The first (F1) is a small active-region filament located near the outskirts of the streamer arcade. It underwent a nonradial eruption, initially moving in the interior of the streamer arcade and resulting in an over-and-out coronal mass ejection. The second filament (F2), a larger quiescent one far away from F1, was clearly disturbed during the F1 eruption. It then underwent a very slow eruption and finally disappeared completely and permanently. Because two belt-shaped diffuse dimmings formed along the footprints of the streamer arcade in the first eruption and persisted throughout the complete disappearance of F2, the eruption series are interpreted as sympathetic: the simple expansion of the common streamer arcade forced by the F1 eruption weakened magnetic flux overlying F2 and thus led to its slow eruption, with the dimming formation indicating their physical connection. Our observations suggest that multiple-arcade bipolar helmet-streamer configurations are appropriate to producing sympathetic eruptions. Combined with the recent observations of unipolar-streamer sympathetic events, it appears that a multiple-arcade unipolar or bipolar helmet streamer can serve as a common magnetic configuration for sympathetic eruptions.

Head and face injuries and helmet use among injured motorcyclists with road accidents in Isfahan, Iran

Directory of Open Access Journals (Sweden)

Azam Dadkhah

2015-10-01

Full Text Available BACKGROUND AND AIM: The study aimed to assess the frequency of head and face injuries in motorcyclists who had an accident and to find out the relationship between helmet use and frequency of these injuries. METHODS: A cross-sectional study with multi-stage sampling method provides data on the injured motorcyclists with road accidents. Data came from a registration form which has documented information of each injured person who had a road accident and hospitalized in the biggest hospital of Isfahan University of Medical Sciences, Iran (Al-Zahra. All the registration forms were surveyed for hospitalization period, treatment costs, severity of injury, and date of accident during 2010 (n = 1626. Later, among the list of injured motorcyclists during the last 3 months of the registration form, 125 cases were randomly selected and interviewed by phone regarding occurrence of the head and face injuries and whether wearing helmet during the accident. Confidence intervals (CI, Chi-square, and Phi and Cramer’s correlation coefficient were applied. The ethical approval was provided. RESULTS: Accident by motorcycle was 31.0% of all road accidents. The frequency of motorcycle accidents was higher in the autumn and among 21-25 year olds. The mean period of hospitalization was 4.3 days and the mean of hospital costs was about 9000000 Rials [about 8200 United States dollar (USD, in 2010]. Of motorcyclist, 35.0% reported they were helmeted when they had the accident. The frequency of head and face injuries was 51.0% among all the injured motorcyclists, 22.0% and 78.0% among the helmeted and non-helmeted motorcyclists, respectively (P = 0.009, r = -0.267. CONCLUSION: Motorcycle accidents comprise a large number of road accidents and cause substantial morbidity and financial impact for the community members. Head and face injuries are the most common trauma in motorcyclists, and the injury rate is higher among non-helmeted motorcyclists.

Similarities and differences between on-scalp and conventional in-helmet magnetoencephalography recordings.

Directory of Open Access Journals (Sweden)

Lau M Andersen

Full Text Available The development of new magnetic sensor technologies that promise sensitivities approaching that of conventional MEG technology while operating at far lower operating temperatures has catalysed the growing field of on-scalp MEG. The feasibility of on-scalp MEG has been demonstrated via benchmarking of new sensor technologies performing neuromagnetic recordings in close proximity to the head surface against state-of-the-art in-helmet MEG sensor technology. However, earlier work has provided little information about how these two approaches compare, or about the reliability of observed differences. Herein, we present such a comparison, based on recordings of the N20m component of the somatosensory evoked field as elicited by electric median nerve stimulation. As expected from the proximity differences between the on-scalp and in-helmet sensors, the magnitude of the N20m activation as recorded with the on-scalp sensor was higher than that of the in-helmet sensors. The dipole pattern of the on-scalp recordings was also more spatially confined than that of the conventional recordings. Our results furthermore revealed unexpected temporal differences in the peak of the N20m component. An analysis protocol was therefore developed for assessing the reliability of this observed difference. We used this protocol to examine our findings in terms of differences in sensor sensitivity between the two types of MEG recordings. The measurements and subsequent analysis raised attention to the fact that great care has to be taken in measuring the field close to the zero-line crossing of the dipolar field, since it is heavily dependent on the orientation of sensors. Taken together, our findings provide reliable evidence that on-scalp and in-helmet sensors measure neural sources in mostly similar ways.

Factors associated with the enactment of safety belt and motorcycle helmet laws.

Science.gov (United States)

Law, Teik Hua; Noland, Robert B; Evans, Andrew W

2013-07-01

It has been shown that road safety laws, such as motorcycle helmet and safety belt laws, have a significant effect in reducing road fatalities. Although an expanding body of literature has documented the effects of these laws on road safety, it remains unclear which factors influence the likelihood that these laws are enacted. This study attempts to identify the factors that influence the decision to enact safety belt and motorcycle helmet laws. Using panel data from 31 countries between 1963 and 2002, our results reveal that increased democracy, education level, per capita income, political stability, and more equitable income distribution within a country are associated with the enactment of road safety laws. © 2012 Society for Risk Analysis.

LWH & ACH Helmet Hardware Study

Science.gov (United States)

2015-11-30

cut in half lengthwise, mounted in epoxy , and polished, as shown in Figure 3, then the grain microstructure examined via optical metallography...saw, and mounted in epoxy and cured at room temperature. Initial manual sanding of the cut surfaces was no coarser than 600 grit silicon-carbide...initial attempts to perform impact tests using screws mounted in Kevlar composite panels resulted in little damage to the screws, but a lot of

Effect of the Oculus Rift head mounted display on postural stability

DEFF Research Database (Denmark)

Epure, Paula; Gheorghe, Cristina; Nissen, Thomas

2014-01-01

board controlling a skiing game. Two tests were conducted: full-vision versus blindfolded and HMD versus monitor display. Results were that five of the six balance-impaired adults and six of the eight non-balance-impaired adults showed higher degree of postural stability while using a monitor display......This study explored how a HMD-experienced virtual environment influences physical balance of six balance-impaired adults 59-69 years-of-age, when compared to a control group of eight non-balance-impaired adults, 18-28 years-of-age. The setup included a Microsoft Kinect and a self-created balance....... Conclusions are that HMD, used in this context, leads to postural instability....

Helmets: A Threat to the Preservation of Women's Lacrosse

Science.gov (United States)

Bull, Ashley; Cavanaugh, Lauren

2016-01-01

A recent debate has raised controversy over the implementation of helmets in the game of women's lacrosse. Women have been participating in this game of finesse and skill without the need for safety equipment, yet in the past decade goggles have been mandated to compensate for the technological advancements in equipment that has increased the…

North Caucasian helmets from the Crimean Tatar Nobility from the Museum of Topkapi Palace (Istanbul, Turkey. Design Features, Design and Combat Use

Directory of Open Access Journals (Sweden)

Leonid A. Bobrov

2016-06-01

Full Text Available The article describes the helmets of the Crimean Tatar nobility stored in the Museum of Topkapi Palace (Istanbul, Republic of Turkey. Based on the analysis of design and system design determined that hats were made of Circassian masters of the XVIII century. Helmet No. 1/810 in shape of the dome relates to the type of bevel. Forged a gilded crown complemented by ornamented Hoop, pads, conical pommel, and ringed barmitsa Persian type. In Cherkessia similar hats were known as Tang (from the Arab. "the Taj", i.e. "crown". It is most likely that the owner of the helmet was the last Noureddine Crimean khanate, Bahadir Giray (1789-1792 was the son of MuminGirei (?-1747 and grandson of Khan Saadet Giray IV (1717-1724. Helmet No. 1/812по the shape of a dome refers to the type of conal. Forged iron gilded crown complemented by ornamented Hoop, plates and funnel-shaped topping. Dome placed on the manufacture date of the helmet – "1180 of the Hijra" (i.e., 1766-1767 in the Gregorian calendar, as well as the inscription: "Owner Sultan Ali", "Muhammad Giray", "Mansour". Helmet No. 1/811по the shape of a dome refers to the type of cylindrical. Faceted iron supplemented gilt crown ornamented Hoop, conical pommel and Aventail Persian type. On the front of hats placed the inscription, "Sultan Mohammed Ibn AdilGiray". This suggests that the owner of the helmet could be the son of Nureddin (1718, serasker Budjaka and Editcol (1727-1728 Adil Ibn Selim I Giray or seraskier EditcolAdil Ibn Selim III Giray (1766-1767. In the framework of the interdisciplinary research were made copies of these helmets, which have become the object of scientific experiments aimed at the study of the functional properties of the considered hats. According to the results of the experimental tests it was found that all three of the helmet provide very reliable protection of the head and neck of the warrior from the cutting and cut-and-cutting blows of the enemy. The saber blade

Markerless client-server augmented reality system with natural features

Science.gov (United States)

Ning, Shuangning; Sang, Xinzhu; Chen, Duo

2017-10-01

A markerless client-server augmented reality system is presented. In this research, the more extensive and mature virtual reality head-mounted display is adopted to assist the implementation of augmented reality. The viewer is provided an image in front of their eyes with the head-mounted display. The front-facing camera is used to capture video signals into the workstation. The generated virtual scene is merged with the outside world information received from the camera. The integrated video is sent to the helmet display system. The distinguishing feature and novelty is to realize the augmented reality with natural features instead of marker, which address the limitations of the marker, such as only black and white, the inapplicability of different environment conditions, and particularly cannot work when the marker is partially blocked. Further, 3D stereoscopic perception of virtual animation model is achieved. The high-speed and stable socket native communication method is adopted for transmission of the key video stream data, which can reduce the calculation burden of the system.

Assessing balance through the use of a low-cost head-mounted display in older adults: a pilot study

Directory of Open Access Journals (Sweden)

Saldana SJ

2017-08-01

Full Text Available Santiago J Saldana,1 Anthony P Marsh,2 W Jack Rejeski,2 Jack K Haberl,2 Peggy Wu,3 Scott Rosenthal,4 Edward H Ip1 1Department of Biostatistical Sciences, Wake Forest School of Medicine, 2Department of Health and Exercise Science, Wake Forest University, Winston-Salem, NC, 3Research and Development, Smart Information Flow Technologies, Minneapolis, MN, 4Wake Forest School of Medicine, Winston-Salem, NC, USA Introduction: As the population ages, the prevention of falls is an increasingly important public health problem. Balance assessment forms an important component of fall-prevention programs for older adults. The recent development of cost-effective and highly responsive virtual reality (VR systems means new methods of balance assessment are feasible in a clinical setting. This proof-of-concept study made use of the submillimeter tracking built into modern VR head-mounted displays (VRHMDs to assess balance through the use of visual–vestibular conflict. The objective of this study was to evaluate the validity, acceptability, and reliability of using a VRHMD to assess balance in older adults.Materials and methods: Validity was assessed by comparing measurements from the VRHMD to measurements of postural sway from a force plate. Acceptability was assessed through the use of the Simulator Sickness Questionnaire pre- and postexposure to assess possible side effects of the visual–vestibular conflict. Reliability was assessed by measuring correlations between repeated measurements 1 week apart. Variables of possible importance that were found to be reliable (r≥0.9 between tests separated by a week were then tested for differences compared to a control group. Assessment was performed as a cross-sectional single-site community center-based study in 13 older adults (≥65 years old, 80.2±7.3 years old, 77% female, five at risk of falls, eight controls. The VR balance assessment consisted of four modules: a baseline module, a reaction module, a

Confinement lowers fertility rate of helmeted guinea fowl ( Numida ...

African Journals Online (AJOL)

... common game bird in Africa and there have been efforts to domesticate it for use as a source of human food. An important obstacle in successful domestication of guinea fowl is their low fertility rate.We studied the effects of semi-confinement on the fertility rates of helmeted guinea fowl by comparing egg fertility, hatch rate ...

Does helmet CPAP reduce cerebral blood flow and volume by comparison with Infant Flow driver CPAP in preterm neonates?

Science.gov (United States)

Zaramella, Patrizia; Freato, Federica; Grazzina, Nicoletta; Saraceni, Elisabetta; Vianello, Andrea; Chiandetti, Lino

2006-10-01

We compared neonatal helmet continuous positive airway pressure (CPAP) and the conventional nasal Infant Flow driver (IFD) CPAP in the noninvasive assessment of absolute cerebral blood flow (CBF) and relative cerebral blood volume changes (DeltaCBV) by near-infrared spectroscopy. A randomized crossover study in a tertiary referral NICU. Assessment of CBF and DeltaCBV in 17 very low birth weight infants with respiratory distress (median age 5 days) treated with two CPAP devices at a continuous distending pressure of 4 mbar. Neonates were studied for two consecutive 60-min periods with helmet CPAP and with IFD CPAP. Basal chromophore traces enabled DeltaCBV changes to be calculated. CBF was calculated in milliliters per 100 grams per minute from the saturation rise integral and rate of rise O(2)Hb-HHb. Median (range) CBF with helmet CPAP was 27.37 (9.47-48.20) vs. IFD CBF 34.74 (13.59-60.10)(p=0.049) and DeltaCBV 0.15 (0.09-0.28) with IFD and 0.13 (0.07-0.27) with helmet CPAP (NS). Using helmet and IFD CPAP, the neonates showed no difference in mean physiological parameters (transcutaneous carbon dioxide and oxygen tension, pulse oximetry saturation, heart rate, breathing rate, mean arterial blood pressure, desaturation rate, axillary temperature). Assessing CBF and DeltaCBV measured by near-infrared spectroscopy with two CPAP devices revealed no differences in relative blood volume, but CBF was lower with helmet CPAP. Greater active vasoconstriction and/or passive capillary and/or venous vessel compression seem the most likely reason, due to a positive pressure around the head, neck, and shoulders by comparison with the airway pressure.

The differences between storms driven by helmet streamer CIRs and storms driven by pseudostreamer CIRs

OpenAIRE

Borovsky, Joseph E.; Denton, Michael

2013-01-01

A corotating interaction region (CIR) is formed when fast coronal hole origin solar wind overtakes slow solar wind and forms a region of compressed plasma and magnetic field. The slow wind upstream of the coronal hole fast wind can be either of helmet streamer origin or pseudostreamer origin. For a collection of 125 CIR-driven geomagnetic storms, the slow wind ahead of each CIR is examined; for those storm not containing ejecta, each CIR is categorized as a helmet streamer CIR (74 of the 125 ...

A new head-mounted display-based augmented reality system in neurosurgical oncology: a study on phantom.

Science.gov (United States)

Cutolo, Fabrizio; Meola, Antonio; Carbone, Marina; Sinceri, Sara; Cagnazzo, Federico; Denaro, Ennio; Esposito, Nicola; Ferrari, Mauro; Ferrari, Vincenzo

2017-12-01

Benefits of minimally invasive neurosurgery mandate the development of ergonomic paradigms for neuronavigation. Augmented Reality (AR) systems can overcome the shortcomings of commercial neuronavigators. The aim of this work is to apply a novel AR system, based on a head-mounted stereoscopic video see-through display, as an aid in complex neurological lesion targeting. Effectiveness was investigated on a newly designed patient-specific head mannequin featuring an anatomically realistic brain phantom with embedded synthetically created tumors and eloquent areas. A two-phase evaluation process was adopted in a simulated small tumor resection adjacent to Broca's area. Phase I involved nine subjects without neurosurgical training in performing spatial judgment tasks. In Phase II, three surgeons were involved in assessing the effectiveness of the AR-neuronavigator in performing brain tumor targeting on a patient-specific head phantom. Phase I revealed the ability of the AR scene to evoke depth perception under different visualization modalities. Phase II confirmed the potentialities of the AR-neuronavigator in aiding the determination of the optimal surgical access to the surgical target. The AR-neuronavigator is intuitive, easy-to-use, and provides three-dimensional augmented information in a perceptually-correct way. The system proved to be effective in guiding skin incision, craniotomy, and lesion targeting. The preliminary results encourage a structured study to prove clinical effectiveness. Moreover, our testing platform might be used to facilitate training in brain tumour resection procedures.

Comparison of an in-helmet temperature monitor system to rectal temperature during exercise.

Science.gov (United States)

Wickwire, P Jason; Buresh, Robert J; Tis, Laurie L; Collins, Mitchell A; Jacobs, Robert D; Bell, Marla M

2012-01-01

Body temperature monitoring is crucial in helping to decrease the amount and severity of heat illnesses; however, a practical method of monitoring temperature is lacking. In response to the lack of a practical method of monitoring the temperature of athletes, Hothead Technologies developed a device (HOT), which continuously monitors an athlete's fluctuations in body temperature. HOT measures forehead temperature inside helmets. The purpose of this study was to compare HOT against rectal temperature (Trec). Male volunteers (n = 29, age = 23.5 ± 4.5 years, weight = 83.8 ± 10.4 kg, height = 180.1 ± 5.8 cm, body fat = 12.3 ± 4.5%) exercised on a treadmill at an intensity of 60-75% heart rate reserve (HRR) (wet bulb globe temperature [WBGT] = 28.7° C) until Trec reached 38.7° C. The correlation between Trec and HOT was 0.801 (R = 0.64, standard error of the estimate (SEE) = 0.25, p = 0.00). One reason for this relatively high correlation is the microclimate that HOT is monitoring. HOT is not affected by the external climate greatly because of its location in the helmet. Therefore, factors such as evaporation do not alter HOT temperature to a great degree. HOT was compared with Trec in a controlled setting, and the exercise used in this study was moderate aerobic exercise, very unlike that used in football. In a controlled laboratory setting, the relationship between HOT and Trec showed favorable correlations. However, in applied settings, helmets are repeatedly removed and replaced forcing HOT to equilibrate to forehead temperature every time the helmet is replaced. Therefore, future studies are needed to mimic how HOT will be used in field situations.

Soldier-worn augmented reality system for tactical icon visualization

Science.gov (United States)

Roberts, David; Menozzi, Alberico; Clipp, Brian; Russler, Patrick; Cook, James; Karl, Robert; Wenger, Eric; Church, William; Mauger, Jennifer; Volpe, Chris; Argenta, Chris; Wille, Mark; Snarski, Stephen; Sherrill, Todd; Lupo, Jasper; Hobson, Ross; Frahm, Jan-Michael; Heinly, Jared

2012-06-01

This paper describes the development and demonstration of a soldier-worn augmented reality system testbed that provides intuitive 'heads-up' visualization of tactically-relevant geo-registered icons. Our system combines a robust soldier pose estimation capability with a helmet mounted see-through display to accurately overlay geo-registered iconography (i.e., navigation waypoints, blue forces, aircraft) on the soldier's view of reality. Applied Research Associates (ARA), in partnership with BAE Systems and the University of North Carolina - Chapel Hill (UNC-CH), has developed this testbed system in Phase 2 of the DARPA ULTRA-Vis (Urban Leader Tactical, Response, Awareness, and Visualization) program. The ULTRA-Vis testbed system functions in unprepared outdoor environments and is robust to numerous magnetic disturbances. We achieve accurate and robust pose estimation through fusion of inertial, magnetic, GPS, and computer vision data acquired from helmet kit sensors. Icons are rendered on a high-brightness, 40°×30° field of view see-through display. The system incorporates an information management engine to convert CoT (Cursor-on-Target) external data feeds into mil-standard icons for visualization. The user interface provides intuitive information display to support soldier navigation and situational awareness of mission-critical tactical information.

Visual Stability of Objects and Environments Viewed through Head-Mounted Displays

Science.gov (United States)

Ellis, Stephen R.; Adelstein, Bernard D.

2015-01-01

Virtual Environments (aka Virtual Reality) is again catching the public imagination and a number of startups (e.g. Oculus) and even not-so-startup companies (e.g. Microsoft) are trying to develop display systems to capitalize on this renewed interest. All acknowledge that this time they will get it right by providing the required dynamic fidelity, visual quality, and interesting content for the concept of VR to take off and change the world in ways it failed to do so in past incarnations. Some of the surprisingly long historical background of the technology that the form of direct simulation that underlies virtual environment and augmented reality displays will be briefly reviewed. An example of a mid 1990's augmented reality display system with good dynamic performance from our lab will be used to illustrate some of the underlying phenomena and technology concerning visual stability of virtual environments and objects during movement. In conclusion some idealized performance characteristics for a reference system will be proposed. Interestingly, many systems more or less on the market now may actually meet many of these proposed technical requirements. This observation leads to the conclusion that the current success of the IT firms trying to commercialize the technology will depend on the hidden costs of using the systems as well as the development of interesting and compelling content.

Effects of ventilated safety helmets in a hot environment

Science.gov (United States)

G.A. Davis; E.D. Edmisten; R.E. Thomas; R.B. Rummer; D.D. Pascoe

2001-01-01

Forest workers are likely to remove head protection in hot and humid conditions because of thermal discomfort. However, a recent Occupational Safety and Health Administration (OSHA) regulation revision requires all workers in logging operations to wear safety helmets, thus creating a compliance problem. To determine which factors contribute to forest workers’ thermal...

Influence of an Enforcement Campaign on Seat-Belt and Helmet Wearing, Karachi-Hala Highway, Pakistan

Science.gov (United States)

Bhatti, Junaid A.; Ejaz, Kiran; Razzak, Junaid A.; Tunio, Israr Ali; Sodhar, Irshad

2011-01-01

This study assessed to what extent an enforcement campaign influenced seat-belt and helmet wearing on a Pakistani highway. The study setting was the Karachi-Hala highway where a traffic enforcement campaign was conducted from Dec 2009 to Feb 2010. Seat-belt and helmet wearing were observed in Nov 2009 and Apr 2010 at Karachi toll plaza. Differences in wearing rates as a function of occupants’ age, sex, and vehicle type were compared between the two periods. On average, 9 119 (Standard deviation=1 896) traffic citations were issued per month from Aug 2009 to Feb 2010; 4.2% of which were for not wearing helmet. A 22.5% increase in citations was observed for Dec 2009 to Feb 2010 periods compared with Aug 2009 to Oct 2009 periods. Nearly six thousand four-wheeled and four hundred two-wheeled motorized vehicle occupants were observed in Nov 2009 and Apr 2010. Overall, two of the five drivers and one of the five front seat occupants wore seat belts. This proportion was significantly higher in drivers and front-seat occupants of cars than those of heavier vehicles. Similarly, one of two motorcyclists used a helmet but this proportion was 5.8% for pillion riders in Nov 2009. The increased enforcement had a limited influence on belt wearing in drivers (+4.0%; 95% Confidence Interval [95%CI]=1.8–6.1) and occupants (+6.2%; 95%CI=4.2–8.2). A higher increase was observed for motorcyclists (+9.8%; 95%CI=2.6–16.8) and pillion riders (+12.8%; 95%CI=5.4, 20.5). These results suggested that serious efforts are required to increase seat-belt and helmet use on Pakistani highways. Improving enforcement resources, increased fines, not allowing such vehicles on roads, and awareness campaigns targeting drivers of heavy vehicles might increase wearing rates in Pakistan. PMID:22105384

PV module mounting method and mounting assembly

Science.gov (United States)

Lenox, Carl J.S.; Johnson, Kurt M.

2013-04-23

A method for mounting PV modules to a deck includes selecting PV module layout pattern so that adjacent PV module edges are spaced apart. PV mounting and support assemblies are secured to the deck according to the layout pattern using fasteners extending into the deck. The PV modules are placed on the PV mounting and support assemblies. Retaining elements are located over and secured against the upper peripheral edge surfaces of the PV modules so to secure them to the deck with the peripheral edges of the PV modules spaced apart from the deck. In some examples a PV module mounting assembly, for use on a shingled deck, comprises flashing, a base mountable on the flashing, a deck-penetrating fastener engageable with the base and securable to the deck so to secure the flashing and the base to the shingled deck, and PV module mounting hardware securable to the base.

Changes in motorcycle-related injuries and deaths after mandatory motorcycle helmet law in a district of Vietnam.

Science.gov (United States)

Ha, Ninh Thi; Ederer, David; Vo, Van Anh Ha; Pham, An Van; Mounts, Anthony; Nolen, Leisha D; Sugerman, David

2018-01-02

Our study measured the change in head injuries and deaths among motorcycle users in Cu Chi district, a suburban district of Ho Chi Minh City. Hospital records for road traffic injuries (RTIs) were collected from the Cu Chi Trauma Centre and motorcycle-related death records were obtained from mortality registries in commune health offices. Head injury severity was categorized using the Abbreviated Injury Score (AIS). Rate ratios (RRs) were used to compare rates pre- and post-law (2005/2006-2009/2010). Cu Chi's population, stratified by year, age, and sex, was used as the denominator. Of records identifying the transportation mode at the time of injury, motorcyclists accounted for most injuries (3,035, 87%) and deaths (238, 90%). Head injuries accounted for 70% of motorcycle-related hospitalizations. Helmet use was not recorded in any death records and not in 97% of medical records. Males accounted for most injuries (73%) and deaths (88%). The median age was 28 years and 32 years for injuries and deaths, respectively. Compared to the pre-law period, rates of motorcycle injuries (RR = 0.53; 95% confidence interval [CI], 0.49-0.58), head injuries (RR = 0.35; 95% CI, 0.31-0.39), severe head injuries (RR = 0.47; 95% CI, 0.34-0.63), and deaths (RR = 0.69; 95% CI, 0.53-0.89) significantly decreased in the post-law period. Rates of head injuries and deaths among motorcycle riders decreased significantly after implementation of the mandatory helmet law in Vietnam. To further examine the impact of the motorcycle helmet law, including compliance and helmet quality, further emphasis should be placed on gathering helmet use data from injured motorcyclists.

Material property determination of the lining layers of a versatile helmet

Directory of Open Access Journals (Sweden)

Kottner Radek

2018-01-01

Full Text Available This paper deals with material property identification of a helmet lining consisting of an outer layer of an expanded polystyrene (EPS and inner layer of an open-closed cell foam (OCCF. A combined numerical simulation and experimental testing was used for the material property identification. Compression and drop tests were performed. The ABAQUS finite element commercial code was used for numerical simulations in which the OOCF was modelled as a rate dependent viscoelastic material, while the EPS as a crushable foam. The reaction force time histories coming from the numerical simulation and the experiment have been used as a criterion for material parameter determination. After the identification of the material properties, numerical drop-tests were used to study the behaviour of a plate and a conical composite OOCF and EPS liners to decide which of them suits more for the helmet.

Cybersickness provoked by head-mounted display affects cutaneous vascular tone, heart rate and reaction time.

Science.gov (United States)

Nalivaiko, Eugene; Davis, Simon L; Blackmore, Karen L; Vakulin, Andrew; Nesbitt, Keith V

2015-11-01

Evidence from studies of provocative motion indicates that motion sickness is tightly linked to the disturbances of thermoregulation. The major aim of the current study was to determine whether provocative visual stimuli (immersion into the virtual reality simulating rides on a rollercoaster) affect skin temperature that reflects thermoregulatory cutaneous responses, and to test whether such stimuli alter cognitive functions. In 26 healthy young volunteers wearing head-mounted display (Oculus Rift), simulated rides consistently provoked vection and nausea, with a significant difference between the two versions of simulation software (Parrot Coaster and Helix). Basal finger temperature had bimodal distribution, with low-temperature group (n=8) having values of 23-29 °C, and high-temperature group (n=18) having values of 32-36 °C. Effects of cybersickness on finger temperature depended on the basal level of this variable: in subjects from former group it raised by 3-4 °C, while in most subjects from the latter group it either did not change or transiently reduced by 1.5-2 °C. There was no correlation between the magnitude of changes in the finger temperature and nausea score at the end of simulated ride. Provocative visual stimulation caused prolongation of simple reaction time by 20-50 ms; this increase closely correlated with the subjective rating of nausea. Lastly, in subjects who experienced pronounced nausea, heart rate was elevated. We conclude that cybersickness is associated with changes in cutaneous thermoregulatory vascular tone; this further supports the idea of a tight link between motion sickness and thermoregulation. Cybersickness-induced prolongation of reaction time raises obvious concerns regarding the safety of this technology. Copyright © 2015 Elsevier Inc. All rights reserved.

Visual comfort of binocular and 3D displays

NARCIS (Netherlands)

Kooi, F.L.; Toet, A.

2004-01-01

Imperfections in binocular image pairs can cause serious viewing discomfort. For example, in stereo vision systems eye strain is caused by unintentional mismatches between the left and right eye images (stereo imperfections). Head-mounted displays can induce eye strain due to optical misalignments.

Miniaturized day/night sight in Soldato Futuro program

Science.gov (United States)

Landini, Alberto; Cocchi, Alessandro; Bardazzi, Riccardo; Sardelli, Mauro; Puntri, Stefano

2013-06-01

The market of the sights for the 5.56 mm assault rifles is dominated by mainly three types of systems: TWS (Thermal Weapon Sight), the Pocket Scope with Weapon Mount and the Clip-on. The latter are designed primarily for special forces and snipers use, while the TWS design is triggered mainly by the DRI (Detection, Recognition, Identification) requirements. The Pocket Scope design is focused on respecting the SWaP (Size, Weight and Power dissipation) requirements. Compared to the TWS systems, for the last two years there was a significant technological growth of the Pocket Scope/Weapon Mount solutions, concentrated on the compression of the overall dimensions. The trend for the assault rifles is the use of small size/light weight (SWaP) IR sights, suitable mainly for close combat operations but also for extraordinary use as pocket scopes - handheld or helmet mounted. The latest developments made by Selex ES S.p.A. are responding precisely to the above-mentioned trend, through a miniaturized Day/Night sight embedding state-of-the art sensors and using standard protocols (USB 2.0, Bluetooth 4.0) for interfacing with PDAs, Wearable computers, etc., while maintaining the "shoot around the corner" capability. Indeed, inside the miniaturized Day/Night sight architecture, a wireless link using Bluetooth technology has been implemented to transmit the video streaming of the rifle sight to an helmet mounted display. The video of the rifle sight is transmitted only to the eye-piece of the soldier shouldering the rifle.

Impact response of US Army and National Football League helmet pad systems

Energy Technology Data Exchange (ETDEWEB)

Moss, W C; King, M J

2011-02-18

Lawrence Livermore National Laboratory [LLNL] was tasked to compare the impact response of NFL helmet pad systems and U.S. Army pad systems compatible with an Advanced Combat Helmet [ACH] at impact velocities up to 20 ft/s. This was a one-year study funded by the U.S. Army and JIEDDO. The Army/JIEDDO point of contact is COL R. Todd Dombroski, DO, JIEDDO Surgeon. LLNL was chosen by committee to perform the research based on prior published computational studies of the mechanical response of helmets and skulls to blast. Our collaborators include the U.S. Army Aeromedical Research Laboratory [USAARL] (a DoD laboratory responsible for impact testing helmets), Team Wendy and Oregon Aero (current and former ACH pad manufacturers), Riddell and Xenith (NFL pad manufacturers), and d3o (general purpose sports pad manufacturer). The manufacturer-supplied pad systems that were studied are shown in the figure below. The first two are the Army systems, which are bilayer foam pads with both hard and soft foam and a water-resistant airtight wrapper (Team Wendy) or a water-resistant airtight coating (Oregon Aero). The next two are NFL pad systems. The Xenith system consists of a thin foam pad and a hollow air-filled cylinder that elastically buckles under load. The Riddell system is a bilayer foam pad that is encased in an inflatable airbag with relief channels to neighboring pads in the helmet. The inflatable airbag is for comfort and provides no enhancement to impact mitigation. The d3o system consists of a rate-sensitive homogeneous dense foam. LLNL performed experiments to characterize the material properties of the individual foam materials and the response of the complete pad systems, to obtain parameters needed for the simulations. LLNL also performed X-ray CT scans of an ACH helmet shell that were used to construct a geometrically accurate computational model of the helmet. Two complementary sets of simulations were performed. The first set of simulations reproduced the

Determination of the 4 mm Gamma Knife helmet relative output factor using a variety of detectors

International Nuclear Information System (INIS)

Tsai, J.-S.; Rivard, Mark J.; Engler, Mark J.; Mignano, John E.; Wazer, David E.; Shucart, William A.

2003-01-01

Though the 4 mm Gamma Knife helmet is used routinely, there is disagreement in the Gamma Knife users community on the value of the 4 mm helmet relative output factor. A range of relative output factors is used, and this variation may impair observations of dose response and optimization of prescribed dose. To study this variation, measurements were performed using the following radiation detectors: silicon diode, diamond detector, radiographic film, radiochromic film, and TLD cubes. To facilitate positioning of the silicon diode and diamond detector, a three-dimensional translation micrometer was used to iteratively determine the position of maximum detector response. Positioning of the films and TLDs was accomplished by manufacturing custom holders for each technique. Results from all five measurement techniques indicate that the 4 mm helmet relative output factor is 0.868±0.014. Within the experimental uncertainties, this value is in good agreement with results obtained by other investigators using diverse techniques

Optimisation of energy absorbing liner for equestrian helmets. Part II: Functionally graded foam liner

International Nuclear Information System (INIS)

Cui, L.; Forero Rueda, M.A.; Gilchrist, M.D.

2009-01-01

The energy absorbing liner of safety helmets was optimised using finite element modelling. In this present paper, a functionally graded foam (FGF) liner was modelled, while keeping the average liner density the same as in a corresponding reference single uniform density liner model. Use of a functionally graded foam liner would eliminate issues regarding delamination and crack propagation between interfaces of different density layers which could arise in liners with discrete density variations. As in our companion Part I paper [Forero Rueda MA, Cui L, Gilchrist MD. Optimisation of energy absorbing liner for equestrian helmets. Part I: Layered foam liner. Mater Des [submitted for publication

Eyewear Computing – Augmenting the Human with Head-mounted Wearable Assistants (Dagstuhl Seminar 16042)

OpenAIRE

Bulling, Andreas; Cakmakci, Ozan; Kunze, Kai; Rehg, James M.

2016-01-01

The seminar was composed of workshops and tutorials on head-mounted eye tracking, egocentric vision, optics, and head-mounted displays. The seminar welcomed 30 academic and industry researchers from Europe, the US, and Asia with a diverse background, including wearable and ubiquitous computing, computer vision, developmental psychology, optics, and human-computer interaction. In contrast to several previous Dagstuhl seminars, we used an ignite talk format to reduce the time of talks to...

Wearable Laser Pointer Versus Head-mounted Display for Tele-guidance Applications?

DEFF Research Database (Denmark)

Jalaliniya, Shahram; Pederson, Thomas; Houben, Steven

2014-01-01

Wearable camera and display technology allow remote collaborators to guide activities performed by human agents located elsewhere. This kind of technology augments the range of human perception and actuation. In this paper we quantitatively determine if wearable laser pointers are viable...

Investigation on the applicability of dust protection helmets in the mining industry. Untersuchungen ueber die Einsatzmoeglichkeiten von Staubschutzhelmen im Bergbau

Energy Technology Data Exchange (ETDEWEB)

Bauer, H.D.; Werner, W.; Fuerst, E.

1984-10-01

In case of static ambient air, leakages for volumes of 25 x 1,5 l/min and air supplies >= 120 l/min or 25 x 2,0 l/min and >= 160 l/min do not occur. The increasing flow rate of moving ambient air leads to an increase of leakages. They show their largest extensions in case of lateral flow. In addition, they expand together with increasing physiological load. Therefore, the inherent air supply should not be below 160 l/min. The comparison of the dust protection helmet 'Airstream AH 1' with two respirators revealed the lowest additional physiological load for the dust protection helmet. Applicability tests in situ resulted in the following principal objections: contamination and scratches on the visor leading to visibility restriction of the wearer, bad fit, weight distribution and helmet dimensions, pressure sores and chafes of sealing parts and edges, lamp installation. Air supply and movement were felt as too high in case of low ambient temperatures, and in case of high temperatures and physiological strain it was considered as too low. There were only few objections against fan noise, weight and impediment by cable and battery. Based on the results, a specification including monitoring and maintenance of the helmet was made and additional tests for DIN design 58 645, item 7, were induced. Furthermore, a proposal regarding helmet optimisation was made.

LWH and ACH Helmet Hardware Study

Science.gov (United States)

2015-11-30

cut in half lengthwise, mounted in epoxy , and polished, as shown in Figure 3, then the grain microstructure examined via optical metallography...saw, and mounted in epoxy and cured at room temperature. Initial manual sanding of the cut surfaces was no coarser than 600 grit silicon-carbide...initial attempts to perform impact tests using screws mounted in Kevlar composite panels resulted in little damage to the screws, but a lot of

Work of breathing using different interfaces in spontaneous positive pressure ventilation: helmet, face-mask, and endotracheal tube.

Science.gov (United States)

Oda, Shinya; Otaki, Kei; Yashima, Nozomi; Kurota, Misato; Matsushita, Sachiko; Kumasaka, Airi; Kurihara, Hutaba; Kawamae, Kaneyuki

2016-08-01

Noninvasive positive pressure ventilation (NPPV) using a helmet is expected to cause inspiratory trigger delay due to the large collapsible and compliant chamber. We compared the work of breathing (WOB) of NPPV using a helmet or a full face-mask with that of invasive ventilation by tracheal intubation. We used a lung model capable of simulating spontaneous breathing (LUNGOO; Air Water Inc., Japan). LUNGOO was set at compliance (C) = 50 mL/cmH2O and resistance (R) = 5 cmH2O/L/s for normal lung simulation, C = 20 mL/cmH2O and R = 5 cmH2O/L/s for restrictive lung, and C = 50 mL/cmH2O and R = 20 cmH2O/L/s for obstructive lung. Muscle pressure was fixed at 25 cmH2O and respiratory rate at 20 bpm. Pressure support ventilation and continuous positive airway pressure were performed with each interface placed on a dummy head made of reinforced plastic that was connected to LUNGOO. We tested the inspiratory WOB difference between the interfaces with various combinations of ventilator settings (positive end-expiratory pressure 5 cmH2O; pressure support 0, 5, and 10 cmH2O). In the normal lung and restrictive lung models, WOB decreased more with the face-mask than the helmet, especially when accompanied by the level of pressure support. In the obstructive lung model, WOB with the helmet decreased compared with the other two interfaces. In the mixed lung model, there were no significant differences in WOB between the three interfaces. NPPV using a helmet is more effective than the other interfaces for WOB in obstructive lung disease.

Sonographic Analysis of Changes in Skull Shape After Cranial Molding Helmet Therapy in Infants With Deformational Plagiocephaly.

Science.gov (United States)

Kwon, Dong Rak

2016-04-01

-The purpose of this study was to investigate the changes in skull shape on sonography after cranial molding helmet therapy in infants with deformational plagiocephaly. -Twenty-six infants who were treated with cranial molding helmet therapy were recruited. Caliper and sonographic measurements were performed. The lateral length of the affected and unaffected sides of the skull and cranial vault asymmetry index were measured with calipers. The occipital angle, defined as the angle between lines projected along the lambdoid sutures of the skull, was calculated by sonography. The occipital angle difference and occipital angle ratio were also measured. All caliper and sonographic measurements were performed in each infant twice before and twice after treatment. -The study group included 12 male and 14 female infants with a mean age ± SD of 6.2 ± 3.5 months. The mean treatment duration was 6.0 ± 2.5 months. The difference in lateral length before and after helmet therapy was significantly greater on the affected skull than the unaffected skull (16.7 ± 12.7 versus 9.0 ± 13.4 mm; P skull than the unaffected skull (-5.7° ± 7.3° versus 4.2° ± 7.9°; P < .01). The cranial vault asymmetry index and occipital angle ratio were significantly reduced after helmet therapy (cranial vault asymmetry index, 9.3% ± 2.3% versus 3.5% ± 3.0%; occipital angle ratio, 1.07 ± 0.05 versus 1.01 ± 0.01; P < .05). -These results suggest that occipital angle measurements using sonography, combined with cephalometry, could provide a better understanding of the therapeutic effects of cranial molding helmet therapy in infants with deformational plagiocephaly. © 2016 by the American Institute of Ultrasound in Medicine.

The Economic Impact of Helmet Use on Motorcycle Accidents: A Systematic Review and Meta-analysis of the Literature from the Past 20 Years.

Science.gov (United States)

Kim, Chang-Yeon; Wiznia, Daniel H; Averbukh, Leon; Dai, Feng; Leslie, Michael P

2015-01-01

The incidence and cost of motorcycle accidents are projected to increase. Motorcycle helmets are accepted as an effective strategy for reducing the morbidity and therefore the cost of motorcycle accidents. Despite this, states have continued to repeal helmet laws in the past 20 years. In addition, variations in the methodologies and outcomes of published reports have contributed to uncertainty regarding the health care dollars saved due to motorcycle helmet use. The purpose of this systematic review and meta-analysis is to clarify the economic impact of motorcycle helmet use. Our primary source was Medline. Search terms included "motorcycle," "motorbike," "motorcycle helmet," "head protective devices," and "cost and cost analysis." The review only included articles that were primary studies, written in English, evaluations of periods after 1994, and published in a peer-reviewed journal. Two independent authors extracted data using predefined data fields. Meta-analysis was done using the R-metafor package. Twelve papers met the criteria for inclusion. Meta-analysis demonstrated that nonhelmeted patients required $12,239 more in hospital costs per patient. Nonhelmeted patients also required more postdischarge care and were more likely to use publicly funded insurance. Studies also found lower injury severity and better hospital course in the helmeted population. Study limitations included selection bias, unclear statistical assumptions, lack of precision measures, confounding variables, and lack of standardization to a common year. Meta-analysis demonstrated an I2 of 67%, attributing a significant proportion of outcome variation to study differences. Motorcycle helmet use reduces morbidity and contributes to significant health care cost savings. Continuing antihelmet legislation will impose a substantial economic burden to the health care system, the government, and the public.

Socioeconomic Inequalities in Nonuse of Seatbelts in Cars and Helmets on Motorcycles among People Living in Kurdistan Province, Iran.

Science.gov (United States)

Moradi, Ghobad; Malekafzali Ardakani, Hossein; Majdzadeh, Reza; Bidarpour, Farzam; Mohammad, Kazem; Holakouie-Naieni, Kourosh

2014-09-01

The aim of this study was to determine the socioeconomic inequalities in nonuse of seatbelts in cars and helmets on motorcycles in Kurdistan Province, west of Iran, 2009. The data used in this study was collected from the data gathered in non-communicable disease surveillance system (NCDSS) in 2009 in Kurdistan. A total of 1000 people were included in this study. The outcome variable of this study was the nonuse of seatbelts and helmets. The socio-economic status (SES) was calculated based on participants' residential area and assets using Principal Component Analysis (PCA) method. The concentration index, concentration curve, and comparison of Odds Ratio (OR) in different SES groups were used to measure the socioeconomic inequalities using logistic regression. In order to determine the contribution of determinants of inequality, decomposition analysis was used. The prevalence of nonuse of seatbelts in cars and helmets on motorcycles were 47.5%, 95%CI [44%, 55%], respectively. The Concentration index was -0.097, CI [-0.148, -0.046]. The OR of nonuse of seatbelts in cars and helmets on motorcycles in the richest group compared with the poorest group was 0.39, 95%CI [0.23, 0.68]. The results of the decomposition analysis showed that 34% of inequalities were due to SES, 47% were due to residential area, and 12% were due to unknown factors. There is a reverse association between SES and nonuse of seatbelts in cars and helmets on motorcycles. This issue must be considered while planning to reduce traffic accidents injuries.

Investigation of the optimal detector arrangement for the helmet-chin PET – A simulation study

Energy Technology Data Exchange (ETDEWEB)

Ahmed, Abdella M., E-mail: abdellanur@gmail.com; Tashima, Hideaki; Yoshida, Eiji; Yamaya, Taiga, E-mail: yamaya.taiga@qst.go.jp

2017-06-21

High sensitivity and high spatial resolution dedicated brain PET scanners are in high demand for early diagnosis of neurodegenerative diseases and studies of brain functions. To meet the demand, we have proposed the helmet-chin PET geometry which has a helmet detector and a chin detector. Our first prototype scanner used 54 4-layer depth-of-interaction (DOI) detectors. The helmet detector of the scanner had three detector rings with different radii arranged on a surface of a hemisphere (with a radius of 126.5 mm) and a top cover detector. Therefore, in this study, for our next development, we propose a spherical arrangement, in which the central axis of each detector points toward the center of the hemisphere, and we optimize the size of the detector crystal block to be arranged on the helmet detector. We simulate the spherical arrangement with the optimized crystal block size and compare its imaging performance with the multi-ring arrangement, which has a similar detector arrangement to that of our first prototype. We conduct Monte Carlo simulation to model the scanners having the 4-layer DOI detectors which consist of LYSO crystals. A dead space of 2 mm is assumed on each side of the crystal blocks such as for wrapping. The size of the crystal block is varied from 4×4 mm{sup 2} to 54×54 mm{sup 2} while fixing the thickness of the crystal block to 20 mm. We find that the crystal block sized at 42×42 mm{sup 2} has the highest sensitivity for a hemispherical phantom. The comparison of the two arrangements with the optimized crystal blocks show that, for the same number of crystal blocks, the spherical arrangement has 17% higher sensitivity for the hemispherical phantom than the multi-ring arrangement. We conclude that the helmet-chin PET with the spherical arrangement constructed from the crystal block sized at 42×42×20 mm{sup 3} has better imaging performance especially at the upper part of the brain compared to the multi-ring arrangement while keeping similar

Materials and design issues for military helmets - Chapter 6

OpenAIRE

Hamouda, A.M.S.; Sohaimi, R.M.; Zaidi, A.M.A.; Abdullah, S.

2012-01-01

Abstract: As weaponry technology has advanced, the ballistic threat to humans has increased significantly. As well as the military, civilians who are exposed to these threats as part of their everyday work require adequate protective equipment. This increasing demand for body armour and ballistic helmets is driving the protective equipment industry to create lightweight, reliable protection adapted for specific applications and marketable to a wide range of consumers. This chapter focuses on ...

Polymethylmethacrylate-based luminescent solar concentrators with bottom-mounted solar cells

International Nuclear Information System (INIS)

Zhang, Yi; Sun, Song; Kang, Rui; Zhang, Jun; Zhang, Ningning; Yan, Wenhao; Xie, Wei; Ding, Jianjun; Bao, Jun; Gao, Chen

2015-01-01

Graphical abstract: - Highlights: • Bottom-mounted luminescent solar concentrators on dye-doped plates were studied. • The mechanism of transport process was proposed. • The fabricated luminescent solar concentrator achieved a gain of 1.38. • Power conversion efficiency of 5.03% was obtained with cell area coverage of 27%. • The lowest cost per watt of $1.89 was optimized with cell area coverage of 18%. - Abstract: Luminescent solar concentrators offer an attractive approach to concentrate sunlight economically without tracking, but the narrow absorption band of luminescent materials hinders their further development. This paper describes bottom-mounted luminescent solar concentrators on dye-doped polymethylmethacrylate plates that absorb not only the waveguided light but also the transmitted sunlight and partial fluorescent light in the escape cone. A series of bottom-mounted luminescent solar concentrators with size of 78 mm × 78 mm × 7 mm were fabricated and their gain and power conversion efficiency were investigated. The transport process of the waveguided light and the relationship between the bottom-mounted cells were studied to optimize the performance of the device. The bottom-mounted luminescent solar concentrator with cell area coverage of 9% displayed a cell gain of 1.38, to our best knowledge, which is the highest value for dye-doped polymethylmethacrylate plate luminescent solar concentrators. Power conversion efficiency as high as 5.03% was obtained with cell area coverage of 27%. Furthermore, the bottom-mounted luminescent solar concentrator was found to have a lowest cost per watt of $1.89 with cell area coverage of 18%. These results suggested that the fabricated bottom-mounted luminescent solar concentrator may have a potential in low-cost building integrated photovoltaic application

Examination of the protective roles of helmet/faceshield and directionality for human head under blast waves.

Science.gov (United States)

Sarvghad-Moghaddam, Hesam; Jazi, Mehdi Salimi; Rezaei, Asghar; Karami, Ghodrat; Ziejewski, Mariusz

2015-01-01

A parametric study was conducted to delineate the efficacy of personal protective equipment (PPE), such as ballistic faceshields and advanced combat helmets, in the case of a blast. The propagations of blast waves and their interactions with an unprotected head, a helmeted one, and a fully protected finite element head model (FEHM) were modeled. The biomechanical parameters of the brain were recorded when the FEHM was exposed to shockwaves from the front, back, top, and bottom. The directional dependent tissue response of the brain and the variable efficiency of PPE with respect to the blast orientation were two major results of this study.

A series of student design projects for improving and modernizing safety helmets

NARCIS (Netherlands)

Beurden, van K.M.M. (Karin); Boer, de J. (Johannes); Stilma, M. (Margot); Teeuw, W.B. (Wouter)

2014-01-01

The Saxion Research Centre for Design and Technology employs many students during research projects. This paper discusses a series of student design projects on safety helmets in the Safety@Work project. At construction sites workers are required to wear personal protective equipment during their

Preliminary Assessment of Primary Flight Display Symbology for Electro- Optic Head-Down Displays

Science.gov (United States)

1991-06-01

information :elated to pitch and power; the vertica! line provides information related to bank and heading. As a result of this geometrica ...steering bar are centered over the aircraft symbol. -n -1-- If the bars are centered, the aircraft is either correcting properly or is flying the desired...a•Isd bas,:ý muve to provide a new pitch command. Roll theading correction ) commands are seen as unbalanced line width, the low command bar side

Predicting bicycle helmet stage-of-change among middle school, high school, and college cyclists from demographic, cognitive, and motivational variables.

Science.gov (United States)

Weiss, Jeffrey; Okun, Morris; Quay, Nancy

2004-09-01

To apply Prochaska's Transtheoretical model of behavior change to bicycle helmet use among middle school, high school, and college students. A battery of questionnaires was administered to cyclists in the seventh and ninth grades and to college students in Phoenix, Arizona (N=797). The battery included: (1) a question to determine respondent's stage of behavior change in Prochaska's Transtheoretical model; (2) items assessing the perceived pros and cons of helmet use; (3) a bicycle safety knowledge test; and (4) demographic information. Forty-three percent of the students were in "Precontemplation," 17% were in either "Contemplation" or "Preparation," 16% were in either "Action" or "Maintenance," and 24% were in the "Relapse" stage of change. Grade, Sex, Knowledge, Pros, and Cons, and the Grade by sex and the Grade by knowledge interactions were significant predictors of helmet use stages. Compared with students in Precontemplation, students in the Contemplation stage were disproportionately younger and had higher Pro scores, lower Con scores, and more knowledge (except in the ninth grade). The Transtheoretical model of behavior change is a viable theoretical framework for designing interventions aimed at increasing bicycle helmet use in children and adolescents.

Photovoltaic mounting/demounting unit

DEFF Research Database (Denmark)

2014-01-01

The present invention relates to a photovoltaic arrangement comprising a photovoltaic assembly comprising a support structure defining a mounting surface onto which a photovoltaic module is detachably mounted; and a mounting/demounting unit comprising at least one mounting/demounting apparatus...... which when the mounting/demounting unit is moved along the mounting surface, causes the photovoltaic module to be mounted or demounted to the support structure; wherein the photovoltaic module comprises a carrier foil and wherein a total thickness of the photo voltaic module is below 500 muiotaeta....... The present invention further relates to an associated method for mounting/demounting photovoltaic modules....

Impact of Helmet Use on Injury and Financial Burden of Motorcycle and Moped Crashes in Hawai‘i: Analysis of a Linked Statewide Database

Science.gov (United States)

Castel, Nikki A; Wong, Linda L; Steinemann, Susan

2016-01-01

Helmet use reduces injury severity, disability, hospital length of stay, and hospital charges in motorcycle riders. The public absorbs billions of dollars annually in hospital charges for unhelmeted, uninsured motorcycle riders. We sought to quantify, on a statewide level, the healthcare burden of unhelmeted motorcycle and moped riders. We examined 1,965 emergency medical service (EMS) reports from motorcycle and moped crashes in Hawai‘i between 2007–2009. EMS records were linked to hospital medical records to assess associations between vehicle type, helmet use, medical charges, diagnoses, and final disposition. Unhelmeted riders of either type of vehicle suffered more head injuries, especially skull fractures (adjusted odds ratio (OR) of 4.48, P motorcycle and moped riders, with a significant (P = .006) difference between helmeted ($27,176) and unhelmeted ($40,217) motorcycle riders. Unhelmeted riders were twice as likely to self-pay (19.3%, versus 9.8% of helmeted riders), and more likely to have Medicaid or a similar income-qualifying insurance plan (13.5% versus 5.0%, respectively). Protective associations with helmet use are stronger among motorcyclists than moped riders, suggesting the protective effect is augmented in higher speed crashes. The public financial burden is higher from unhelmeted riders who sustain more severe injuries and are less likely to be insured. PMID:27980882

Preliminary Effect of Synthetic Vision Systems Displays to Reduce Low-Visibility Loss of Control and Controlled Flight Into Terrain Accidents

Science.gov (United States)

Glaab, Louis J.; Takallu, Mohammad A.

2002-01-01

An experimental investigation was conducted to study the effectiveness of Synthetic Vision Systems (SVS) flight displays as a means of eliminating Low Visibility Loss of Control (LVLOC) and Controlled Flight Into Terrain (CFIT) accidents by low time general aviation (GA) pilots. A series of basic maneuvers were performed by 18 subject pilots during transition from Visual Meteorological Conditions (VMC) to Instrument Meteorological Conditions (IMC), with continued flight into IMC, employing a fixed-based flight simulator. A total of three display concepts were employed for this evaluation. One display concept, referred to as the Attitude Indicator (AI) replicated instrumentation common in today's General Aviation (GA) aircraft. The second display concept, referred to as the Electronic Attitude Indicator (EAI), featured an enlarged attitude indicator that was more representative of a glass display that also included advanced flight symbology, such as a velocity vector. The third concept, referred to as the SVS display, was identical to the EAI except that computer-generated terrain imagery replaced the conventional blue-sky/brown-ground of the EAI. Pilot performance parameters, pilot control inputs and physiological data were recorded for post-test analysis. Situation awareness (SA) and qualitative pilot comments were obtained through questionnaires and free-form interviews administered immediately after the experimental session. Initial pilot performance data were obtained by instructor pilot observations. Physiological data (skin temperature, heart rate, and muscle flexure) were also recorded. Preliminary results indicate that far less errors were committed when using the EAI and SVS displays than when using conventional instruments. The specific data example examined in this report illustrates the benefit from SVS displays to avoid massive loss of SA conditions. All pilots acknowledged the enhanced situation awareness provided by the SVS display concept. Levels of

X-ray, synchrotron, and neutron diffraction analysis of Roman cavalry parade helmet fragment

Czech Academy of Sciences Publication Activity Database

Smrcok, L.; Petrik, I.; Langer, V.; Filinchuk, Y.; Beran, Přemysl

2010-01-01

Roč. 45, č. 10 (2010), s. 1025-1031 ISSN 0232-1300 Institutional research plan: CEZ:AV0Z10480505 Keywords : archaeometry * Roman helmet * phase analysis Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 0.946, year: 2010

Neck Muscle Fatigue with Helmet-Mounted Systems

National Research Council Canada - National Science Library

Eveland, Edward S; Pellettiere, Joseph A

2006-01-01

.... Changes in neck muscle strength were identified along with EMG evidence of fatigue. When flights occurred on an almost daily basis over 4 days, the force imparted to the neck was reduced each day...

A Qualitative Method to Estimate HSI Display Complexity

International Nuclear Information System (INIS)

Hugo, Jacques; Gertman, David

2013-01-01

There is mounting evidence that complex computer system displays in control rooms contribute to cognitive complexity and, thus, to the probability of human error. Research shows that reaction time increases and response accuracy decreases as the number of elements in the display screen increase. However, in terms of supporting the control room operator, approaches focusing on addressing display complexity solely in terms of information density and its location and patterning, will fall short of delivering a properly designed interface. This paper argues that information complexity and semantic complexity are mandatory components when considering display complexity and that the addition of these concepts assists in understanding and resolving differences between designers and the preferences and performance of operators. This paper concludes that a number of simplified methods, when combined, can be used to estimate the impact that a particular display may have on the operator's ability to perform a function accurately and effectively. We present a mixed qualitative and quantitative approach and a method for complexity estimation

Integrated Display and Environmental Awareness System - System Architecture Definition

Science.gov (United States)

Doule, Ondrej; Miranda, David; Hochstadt, Jake

2017-01-01

The Integrated Display and Environmental Awareness System (IDEAS) is an interdisciplinary team project focusing on the development of a wearable computer and Head Mounted Display (HMD) based on Commercial-Off-The-Shelf (COTS) components for the specific application and needs of NASA technicians, engineers and astronauts. Wearable computers are on the verge of utilization trials in daily life as well as industrial environments. The first civil and COTS wearable head mounted display systems were introduced just a few years ago and they probed not only technology readiness in terms of performance, endurance, miniaturization, operability and usefulness but also maturity of practice in perspective of a socio-technical context. Although the main technical hurdles such as mass and power were addressed as improvements on the technical side, the usefulness, practicality and social acceptance were often noted on the side of a broad variety of humans' operations. In other words, although the technology made a giant leap, its use and efficiency still looks for the sweet spot. The first IDEAS project started in January 2015 and was concluded in January 2017. The project identified current COTS systems' capability at minimum cost and maximum applicability and brought about important strategic concepts that will serve further IDEAS-like system development.

Head orientation prediction: delta quaternions versus quaternions.

Science.gov (United States)

Himberg, Henry; Motai, Yuichi

2009-12-01

Display lag in simulation environments with helmet-mounted displays causes a loss of immersion that degrades the value of virtual/augmented reality training simulators. Simulators use predictive tracking to compensate for display lag, preparing display updates based on the anticipated head motion. This paper proposes a new method for predicting head orientation using a delta quaternion (DQ)-based extended Kalman filter (EKF) and compares the performance to a quaternion EKF. The proposed framework operates on the change in quaternion between consecutive data frames (the DQ), which avoids the heavy computational burden of the quaternion motion equation. Head velocity is estimated from the DQ by an EKF and then used to predict future head orientation. We have tested the new framework with captured head motion data and compared it with the computationally expensive quaternion filter. Experimental results indicate that the proposed DQ method provides the accuracy of the quaternion method without the heavy computational burden.

Incorporating Data Link Features into a Multi-Function Display to Support Self-Separation and Spacing Tasks for General Aviation Pilots

Science.gov (United States)

Adams, Catherine A.; Murdoch, Jennifer L.; Consiglio, Maria C.; WIlliams, Daniel M.

2005-01-01

One objective of the Small Aircraft Transportation System (SATS) Higher Volume Operations (HVO) project is to increase the capacity and utilization of small non-towered, non-radar equipped airports by transferring traffic management activities to an automated Airport Management Module (AMM) and separation responsibilities to general aviation (GA) pilots. Implementation of this concept required the development of a research Multi-Function Display (MFD) to support the interactive communications between pilots and the AMM. The interface also had to accommodate traffic awareness, self-separation, and spacing tasks through dynamic messaging and symbology for flight path conformance and conflict detection and alerting (CDA). The display served as the mechanism to support the examination of the viability of executing instrument operations designed for SATS designated airports. Results of simulation and flight experiments conducted at the National Aeronautics and Space Administration's (NASA) Langley Research Center indicate that the concept, as facilitated by the research MFD, did not increase pilots subjective workload levels or reduce their situation awareness (SA). Post-test usability assessments revealed that pilots preferred using the enhanced MFD to execute flight procedures, reporting improved SA over conventional instrument flight rules (IFR) procedures.

Evaluation of the Effects of Variable Helmet Weight on Human Response During Lateral +Gy Impact

National Research Council Canada - National Science Library

Perry, Chris

2003-01-01

.... A series of tests was conducted by AFRL/HEPA on a horizontal impulse accelerator using human subjects to investigate the effects of helmet inertial properties on human response to short duration...

Display and Sexual Activities of the Little Cormorant, Phalacrocorax niger (Ciconiformes: Phalacrocoracidae) in Captivity

International Nuclear Information System (INIS)

Naher, Habibon; Sarker Noor Jahan

2008-01-01

Display and sexual activities of the little cormorant (Phalacrocorax niger) was studied on 19 birds from November 2000 to December 2001. The study was conducted in captivity in the Dhaka Zoo, Mirpur. Displaying behavior commenced in mid February. The male took initiative to select the nest site mostly in trees especially in vertical forked branches. The twigs of peacock flower (Caesalpinia pulcherrima) were used as nesting materials. After the response of the female the bisexual displays started. During this time the male and female always sat together and displayed. Within 1 to 2 days of mutual displays the female ate regurgitated foods from the gular pouch of the male. With this the pair formation occurred permanently. Within 2 to 3 days of pair formation mounting took place. At the end of mounting the male flew away and the female jerked her body and ruffed her feathers. Then the male started to collect nesting materials but both of the male and female placed it together on to the nest, giving more or less a circular cup-like shape. The time required in nest building was 14 to 16 days. (author)

Photovoltaic module mounting system

Science.gov (United States)

Miros, Robert H. J. [Fairfax, CA; Mittan, Margaret Birmingham [Oakland, CA; Seery, Martin N [San Rafael, CA; Holland, Rodney H [Novato, CA

2012-04-17

A solar array mounting system having unique installation, load distribution, and grounding features, and which is adaptable for mounting solar panels having no external frame. The solar array mounting system includes flexible, pedestal-style feet and structural links connected in a grid formation on the mounting surface. The photovoltaic modules are secured in place via the use of attachment clamps that grip the edge of the typically glass substrate. The panel mounting clamps are then held in place by tilt brackets and/or mid-link brackets that provide fixation for the clamps and align the solar panels at a tilt to the horizontal mounting surface. The tilt brackets are held in place atop the flexible feet and connected link members thus creating a complete mounting structure.

Magnetic core mounting system

Science.gov (United States)

Ronning, Jeffrey J.

2002-01-01

A mounting apparatus for an electromagnetic device such as a transformer of inductor includes a generally planar metallic plate as a first heat sink, and a metallic mounting cup as a second heat sink. The mounting cup includes a cavity configured to receive the electromagnetic device, the cavity being defined by a base, and an axially-extending annular sidewall extending from the base to a flange portion of the mounting cup. The mounting cup includes first and second passages for allowing the leads of first and second windings of the electromagnetic device to be routed out of the cavity. The cavity is filled with a polyurethane potting resin, and the mounting cup, including the potted electromagnetic device, is mounted to the plate heat sink using fasteners. The mounting cup, which surrounds the electromagnetic device, in combination with the potting resin provides improved thermal transfer to the plate heat sink, as well as providing resistance to vibration and shocks.

Successful Removal of Football Helmet Face-Mask Clips After 1 Season of Use

Science.gov (United States)

Scibek, Jason S.; Gatti, Joseph M.; McKenzie, Jennifer I.

2012-01-01

Context Whereas many researchers have assessed the ability to remove loop straps in traditional face-mask attachment systems after at least 1 season of use, research in which the effectiveness of the Riddell Quick Release (QR) Face Guard Attachment System clip after 1 season has been assessed is limited. Objective To examine the success rate of removing the QR clips after 1 season of use at the Football Championship Subdivision level. We hypothesized that 1 season of use would negatively affect the removal rate of the QR clip but repeated clip-removal trials would improve the removal rate. Design Retrospective, quasi-experimental design. Setting Controlled laboratory study. Patients or Other Participants Sixty-three football helmets from a National Collegiate Athletic Association Division I university located in western Pennsylvania used during the 2008 season were tested. Intervention(s) Three certified athletic trainers (2 men, 1 woman; age = 31.3 ± 3.06 years, time certified = 9.42 ± 2.65 years) attempted to remove the QR clips from each helmet with the tool provided by the manufacturer. Helmets then were reassembled to allow each athletic trainer to attempt clip removal. Main Outcome Measure(s) The dependent variables were total left clips removed (TCR-L), total right clips removed (TCR-R), and total clips removed (TCR). Success rate of clip removal (SRCR) also was assessed. Results Percentages for TCR-L, TCR-R, and TCR were 100% (189 of 189), 96.30% (182 of 189), and 98.15% (371 of 378), respectively. A paired-samples t test revealed a difference between TCR-R and TCR-L (t188 = −2.689, P = .008, μd = 0.037, 95% confidence interval [CI] = −0.064, −0.010). The percentage for SRCR was 96.30% (n = 182), whereas SRCR percentages for trials 1, 2, and 3 were 95.24% (n = 60), 98.41% (n = 62), and 95.24% (n = 60), respectively, and did not represent a difference (F2,186 = 0.588, P = .56, 95% CI = 0.94, 0.99). Conclusions Our results indicated favorable and

Optoelectronic Mounting Structure

Science.gov (United States)

Anderson, Gene R.; Armendariz, Marcelino G.; Baca, Johnny R. F.; Bryan, Robert P.; Carson, Richard F.; Chu, Dahwey; Duckett, III, Edwin B.; McCormick, Frederick B.; Peterson, David W.; Peterson, Gary D.; Reber, Cathleen A.; Reysen, Bill H.

2004-10-05

An optoelectronic mounting structure is provided that may be used in conjunction with an optical transmitter, receiver or transceiver module. The mounting structure may be a flexible printed circuit board. Thermal vias or heat pipes in the head region may transmit heat from the mounting structure to the heat spreader. The heat spreader may provide mechanical rigidity or stiffness to the heat region. In another embodiment, an electrical contact and ground plane may pass along a surface of the head region so as to provide an electrical contact path to the optoelectronic devices and limit electromagnetic interference. In yet another embodiment, a window may be formed in the head region of the mounting structure so as to provide access to the heat spreader. Optoelectronic devices may be adapted to the heat spreader in such a manner that the devices are accessible through the window in the mounting structure.

Louisiana motorcycle fatalities in the wake of governmentally implemented change: a retrospective analysis of the motorcycle morbidity and mortality before, during, and after the repeal of a statewide helmet mandate.

Science.gov (United States)

Strom, Shane F; Ambekar, Sudheer; Madhugiri, Venkatesh S; Nanda, Anil

2013-06-01

On August 15, 2004, Louisiana's universal motorcycle helmet mandate was reinstated. Previous studies have shown that mortality and morbidity of motorcycle riders who crashed had increased during the 5 years the mandate was repealed. The objective of this study was to discern whether the reinstatement of the universal helmet mandate has resulted in a subsequent decrease in motorcycle-related mortality and morbidity in the state of Louisiana. A retrospective analysis was performed observing the regularity of helmet use and the associated morbidity and mortality of motorcycle traffic accidents from the time before, during, and after the universal motorcycle helmet mandate was repealed in the state of Louisiana. Fatality statistics were obtained through the National Highway Safety Traffic Association. Injury, helmet use, and collision data were obtained from the Louisiana Highway Safety Commission. Motorcycle registration data were obtained from the Federal Highway Administration. Motorcycle crash-related fatalities increased significantly when the statewide helmet mandate was repealed, and interestingly, after reinstatement, these fatality rates never returned to their previous lows. Motorcycle fatalities have increased out of proportion to the increase in motorbike registrations, even when yearly fatalities are normalized to fatalities per 10,000 registered bikes. An all-time high in fatalities was seen in 2006, a year subsequent to the mandate's reinstatement. Fatalities per collision were elevated significantly after the mandate's repeal but did not return to prerepeal lows after the mandate's reinstatement. Although helmet use after reinstatement has reached all-time highs, fatality rates have remained elevated since the original mandate repeal in 1999. Other achievable changes in state policy and law enforcement should be explored to quell this heightened risk to motorcycle enthusiasts in Louisiana, and states considering changing their own motorcycle helmet

A Qualitative Method to Estimate HSI Display Complexity

Energy Technology Data Exchange (ETDEWEB)

Hugo, Jacques; Gertman, David [Idaho National Laboratory, Idaho (United States)

2013-04-15

There is mounting evidence that complex computer system displays in control rooms contribute to cognitive complexity and, thus, to the probability of human error. Research shows that reaction time increases and response accuracy decreases as the number of elements in the display screen increase. However, in terms of supporting the control room operator, approaches focusing on addressing display complexity solely in terms of information density and its location and patterning, will fall short of delivering a properly designed interface. This paper argues that information complexity and semantic complexity are mandatory components when considering display complexity and that the addition of these concepts assists in understanding and resolving differences between designers and the preferences and performance of operators. This paper concludes that a number of simplified methods, when combined, can be used to estimate the impact that a particular display may have on the operator's ability to perform a function accurately and effectively. We present a mixed qualitative and quantitative approach and a method for complexity estimation.

Liner mounting assembly

Science.gov (United States)

Halila, Ely E. (Inventor)

1994-01-01

A mounting assembly includes an annular supporting flange disposed coaxially about a centerline axis which has a plurality of circumferentially spaced apart supporting holes therethrough. An annular liner is disposed coaxially with the supporting flange and includes a plurality of circumferentially spaced apart mounting holes aligned with respective ones of the supporting holes. Each of a plurality of mounting pins includes a proximal end fixedly joined to the supporting flange through a respective one of the supporting holes, and a distal end disposed through a respective one of the liner mounting holes for supporting the liner to the supporting flange while unrestrained differential thermal movement of the liner relative to the supporting flange.

Emergency Face-Mask Removal Effectiveness: A Comparison of Traditional and Nontraditional Football Helmet Face-Mask Attachment Systems

Science.gov (United States)

Swartz, Erik E.; Belmore, Keith; Decoster, Laura C.; Armstrong, Charles W.

2010-01-01

Abstract Context: Football helmet face-mask attachment design changes might affect the effectiveness of face-mask removal. Objective: To compare the efficiency of face-mask removal between newly designed and traditional football helmets. Design: Controlled laboratory study. Setting: Applied biomechanics laboratory. Participants: Twenty-five certified athletic trainers. Intervention(s): The independent variable was face-mask attachment system on 5 levels: (1) Revolution IQ with Quick Release (QR), (2) Revolution IQ with Quick Release hardware altered (QRAlt), (3) traditional (Trad), (4) traditional with hardware altered (TradAlt), and (5) ION 4D (ION). Participants removed face masks using a cordless screwdriver with a back-up cutting tool or only the cutting tool for the ION. Investigators altered face-mask hardware to unexpectedly challenge participants during removal for traditional and Revolution IQ helmets. Participants completed each condition twice in random order and were blinded to hardware alteration. Main Outcome Measure(s): Removal success, removal time, helmet motion, and rating of perceived exertion (RPE). Time and 3-dimensional helmet motion were recorded. If the face mask remained attached at 3 minutes, the trial was categorized as unsuccessful. Participants rated each trial for level of difficulty (RPE). We used repeated-measures analyses of variance (α  =  .05) with follow-up comparisons to test for differences. Results: Removal success was 100% (48 of 48) for QR, Trad, and ION; 97.9% (47 of 48) for TradAlt; and 72.9% (35 of 48) for QRAlt. Differences in time for face-mask removal were detected (F4,20  =  48.87, P  =  .001), with times ranging from 33.96 ± 14.14 seconds for QR to 99.22 ± 20.53 seconds for QRAlt. Differences were found in range of motion during face-mask removal (F4,20  =  16.25, P  =  .001), with range of motion from 10.10° ± 3.07° for QR to 16.91° ± 5.36° for TradAlt. Differences also were detected

Emergency face-mask removal effectiveness: a comparison of traditional and nontraditional football helmet face-mask attachment systems.

Science.gov (United States)

Swartz, Erik E; Belmore, Keith; Decoster, Laura C; Armstrong, Charles W

2010-01-01

Football helmet face-mask attachment design changes might affect the effectiveness of face-mask removal. To compare the efficiency of face-mask removal between newly designed and traditional football helmets. Controlled laboratory study. Applied biomechanics laboratory. Twenty-five certified athletic trainers. The independent variable was face-mask attachment system on 5 levels: (1) Revolution IQ with Quick Release (QR), (2) Revolution IQ with Quick Release hardware altered (QRAlt), (3) traditional (Trad), (4) traditional with hardware altered (TradAlt), and (5) ION 4D (ION). Participants removed face masks using a cordless screwdriver with a back-up cutting tool or only the cutting tool for the ION. Investigators altered face-mask hardware to unexpectedly challenge participants during removal for traditional and Revolution IQ helmets. Participants completed each condition twice in random order and were blinded to hardware alteration. Removal success, removal time, helmet motion, and rating of perceived exertion (RPE). Time and 3-dimensional helmet motion were recorded. If the face mask remained attached at 3 minutes, the trial was categorized as unsuccessful. Participants rated each trial for level of difficulty (RPE). We used repeated-measures analyses of variance (α  =  .05) with follow-up comparisons to test for differences. Removal success was 100% (48 of 48) for QR, Trad, and ION; 97.9% (47 of 48) for TradAlt; and 72.9% (35 of 48) for QRAlt. Differences in time for face-mask removal were detected (F(4,20)  =  48.87, P  =  .001), with times ranging from 33.96 ± 14.14 seconds for QR to 99.22 ± 20.53 seconds for QRAlt. Differences were found in range of motion during face-mask removal (F(4,20)  =  16.25, P  =  .001), with range of motion from 10.10° ± 3.07° for QR to 16.91° ± 5.36° for TradAlt. Differences also were detected in RPE during face-mask removal (F(4,20)  =  43.20, P  =  .001), with participants reporting average

Review of Research On Guidance for Recovery from Pitch Axis Upsets

Science.gov (United States)

Harrison, Stephanie J.

2016-01-01

A literature review was conducted to identify past efforts in providing control guidance for aircraft upset recovery including stall recovery. Because guidance is integrally linked to the intended function of aircraft attitude awareness and upset recognition, it is difficult, if not impossible, to consider these issues separately. This literature review covered the aspects of instrumentation and display symbologies for attitude awareness, aircraft upset recognition, upset and stall alerting, and control guidance. Many different forms of symbology have been investigated including, but not limited to, pitch scale depictions, attitude indicator icons, horizon symbology, attitude recovery arrows, and pitch trim indicators. Past research on different visual and alerting strategies that provide advisories, cautions, and warnings to pilots before entering an unusual attitude (UA) are also discussed. Finally, potential control guidance for recovery from upset or unusual attitudes, including approach-to-stall and stall conditions, are reviewed. Recommendations for future research are made.

Cognitive Cost of Using Augmented Reality Displays.

Science.gov (United States)

Baumeister, James; Ssin, Seung Youb; ElSayed, Neven A M; Dorrian, Jillian; Webb, David P; Walsh, James A; Simon, Timothy M; Irlitti, Andrew; Smith, Ross T; Kohler, Mark; Thomas, Bruce H

2017-11-01

This paper presents the results of two cognitive load studies comparing three augmented reality display technologies: spatial augmented reality, the optical see-through Microsoft HoloLens, and the video see-through Samsung Gear VR. In particular, the two experiments focused on isolating the cognitive load cost of receiving instructions for a button-pressing procedural task. The studies employed a self-assessment cognitive load methodology, as well as an additional dual-task cognitive load methodology. The results showed that spatial augmented reality led to increased performance and reduced cognitive load. Additionally, it was discovered that a limited field of view can introduce increased cognitive load requirements. The findings suggest that some of the inherent restrictions of head-mounted displays materialize as increased user cognitive load.

Displays mounted on cutting blocks reduce the learning curve in navigated total knee arthroplasty.

Science.gov (United States)

Schnurr, Christoph; Eysel, Peer; König, Dietmar Pierre

2011-01-01

The use of computer navigation in total knee arthroplasty (TKA) improves the implant alignment but increases the operation time. Studies have shown that the operation time is further prolonged due to the surgeon's learning curve, and longer operation times have been associated with higher morbidity risks. It has been our hypothesis that an improvement in the human-machine interface might reduce the time required during the learning curve. Accordingly, we asked whether the use of navigation devices with a display fixed on the surgical instruments would reduce the operation time in navigated TKAs performed by navigation beginners. Thirty medical students were randomized and used two navigation devices in rotation: these were the Kolibri® device with an external display and the Dash® device with a display that was fixed on the cutting blocks. The time for adjustment of the tibial and femoral cutting blocks on knee models while using these devices was measured. A significant time reduction was demonstration when the Dash® device was used: The time reduction was 21% for the tibial block (p = 0.007), 40% for the femoral block (p learning curve may be diminished.

The motivational safety helmet : Redesign suggestions improving the intrinsic motivation of construction site workers

NARCIS (Netherlands)

Beldman, T. (Teunis); Boer, de J. (Johannes); Lemmens, P. (Pim); Stilma, M. (Margot)

2014-01-01

In reaction to the lack of intrinsic motivation of construction site workers, to wear their safety helmets at all times, a series of research projects studied causes and possible solutions. Goal is to gain an inspirational discussion to get the design onto the next level. This paper describes a

Impact of automatic calibration techniques on HMD life cycle costs and sustainable performance

Science.gov (United States)

Speck, Richard P.; Herz, Norman E., Jr.

2000-06-01

Automatic test and calibration has become a valuable feature in many consumer products--ranging from antilock braking systems to auto-tune TVs. This paper discusses HMDs (Helmet Mounted Displays) and how similar techniques can reduce life cycle costs and increase sustainable performance if they are integrated into a program early enough. Optical ATE (Automatic Test Equipment) is already zeroing distortion in the HMDs and thereby making binocular displays a practical reality. A suitcase sized, field portable optical ATE unit could re-zero these errors in the Ready Room to cancel the effects of aging, minor damage and component replacement. Planning on this would yield large savings through relaxed component specifications and reduced logistic costs. Yet, the sustained performance would far exceed that attained with fixed calibration strategies. Major tactical benefits can come from reducing display errors, particularly in information fusion modules and virtual `beyond visual range' operations. Some versions of the ATE described are in production and examples of high resolution optical test data will be discussed.

Accelerometer method and apparatus for integral display and control functions

Science.gov (United States)

Bozeman, Richard J., Jr.

1992-06-01

Vibration analysis has been used for years to provide a determination of the proper functioning of different types of machinery, including rotating machinery and rocket engines. A determination of a malfunction, if detected at a relatively early stage in its development, will allow changes in operating mode or a sequenced shutdown of the machinery prior to a total failure. Such preventative measures result in less extensive and/or less expensive repairs, and can also prevent a sometimes catastrophic failure of equipment. Standard vibration analyzers are generally rather complex, expensive, and of limited portability. They also usually result in displays and controls being located remotely from the machinery being monitored. Consequently, a need exists for improvements in accelerometer electronic display and control functions which are more suitable for operation directly on machines and which are not so expensive and complex. The invention includes methods and apparatus for detecting mechanical vibrations and outputting a signal in response thereto. The apparatus includes an accelerometer package having integral display and control functions. The accelerometer package is suitable for mounting upon the machinery to be monitored. Display circuitry provides signals to a bar graph display which may be used to monitor machine condition over a period of time. Control switches may be set which correspond to elements in the bar graph to provide an alert if vibration signals increase over the selected trip point. The circuitry is shock mounted within the accelerometer housing. The method provides for outputting a broadband analog accelerometer signal, integrating this signal to produce a velocity signal, integrating and calibrating the velocity signal before application to a display driver, and selecting a trip point at which a digitally compatible output signal is generated. The benefits of a vibration recording and monitoring system with controls and displays readily

Children should wear helmets while ice-skating: a comparison of skating-related injuries.

Science.gov (United States)

McGeehan, Jennifer; Shields, Brenda J; Smith, Gary A

2004-07-01

This study compares injuries, especially head injuries, among ice-skaters with those among skateboarders, rollerskaters, and in-line skaters, to determine the need for helmet use during recreational ice-skating by children. A comparative study of a consecutive series of patients. The emergency department of a large, urban, academic, children's hospital. Children treated for injuries related to recreational ice-skating, skateboarding, rollerskating, and in-line skating. During a 31-month period, 419 consecutive children were evaluated in the emergency department for skating-related injuries. Children were predominantly male (53.9%), with a mean age of 10.0 years (SD: 3.0 years; median: 10.0 years; range: 1-18 years). The most frequent mechanism of injury was a fall. Overall, 76.5% of children (215 of 281 children) were reported to be wearing no protective equipment, such as a helmet or padding on the elbows or knees, at the time of injury. Ice-skaters were more likely to have adult supervision than were skateboarders (relative risk [RR]: 5.16; 95% confidence interval [CI]: 2.13-12.46), rollerskaters (RR: 1.21; 95% CI: 1.09-1.35), and in-line skaters (RR: 2.08; 95% CI: 1.72-2.51). Ice-skaters were at greater risk of injury to the head (20.0%) than were in-line skaters (4.9%) (RR: 4.09; 95% CI: 1.81-9.23); a weak difference was noted between ice-skaters and rollerskaters (9.9%) (RR: 2.18; 95% CI: 1.04-4.57), with no significant difference in head injuries between ice-skaters and skateboarders (15.9%) (RR: 1.60; 95% CI: 0.54-2.93). Ice-skaters demonstrated lacerations to the head in 68.8% of abnormal head examinations, compared with 37.0% for rollerskaters (RR: 1.86; 95% CI: 1.08-3.20) and 50.0% for in-line skaters (RR: 2.06; 95% CI: 1.35-3.16); however, there was no significant difference in lacerations to the head between ice-skaters and skateboarders (53.3%) (RR: 1.29; 95% CI: 0.76-2.19). Injuries to ice-skaters occurred more often in an indoor skating facility (92

42 CFR 84.135 - Half-mask facepieces, full facepieces, hoods, and helmets; fit; minimum requirements.

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Half-mask facepieces, full facepieces, hoods, and... OF RESPIRATORY PROTECTIVE DEVICES Supplied-Air Respirators § 84.135 Half-mask facepieces, full facepieces, hoods, and helmets; fit; minimum requirements. (a) Half-mask facepieces and full facepieces shall...

Shoulder-Mounted Robot for MRI-guided arthrography: Accuracy and mounting study.

Science.gov (United States)

Monfaredi, R; Wilson, E; Sze, R; Sharma, K; Azizi, B; Iordachita, I; Cleary, K

2015-08-01

A new version of our compact and lightweight patient-mounted MRI-compatible 4 degree-of-freedom (DOF) robot for MRI-guided arthrography procedures is introduced. This robot could convert the traditional two-stage arthrography procedure (fluoroscopy-guided needle insertion followed by a diagnostic MRI scan) to a one-stage procedure, all in the MRI suite. The results of a recent accuracy study are reported. A new mounting technique is proposed and the mounting stability is investigated using optical and electromagnetic tracking on an anthropomorphic phantom. Five volunteer subjects including 2 radiologists were asked to conduct needle insertion in 4 different random positions and orientations within the robot's workspace and the displacement of the base of the robot was investigated during robot motion and needle insertion. Experimental results show that the proposed mounting method is stable and promising for clinical application.

New portable FELIX 3D display

Science.gov (United States)

Langhans, Knut; Bezecny, Daniel; Homann, Dennis; Bahr, Detlef; Vogt, Carsten; Blohm, Christian; Scharschmidt, Karl-Heinz

1998-04-01

An improved generation of our 'FELIX 3D Display' is presented. This system is compact, light, modular and easy to transport. The created volumetric images consist of many voxels, which are generated in a half-sphere display volume. In that way a spatial object can be displayed occupying a physical space with height, width and depth. The new FELIX generation uses a screen rotating with 20 revolutions per second. This target screen is mounted by an easy to change mechanism making it possible to use appropriate screens for the specific purpose of the display. An acousto-optic deflection unit with an integrated small diode pumped laser draws the images on the spinning screen. Images can consist of up to 10,000 voxels at a refresh rate of 20 Hz. Currently two different hardware systems are investigated. The first one is based on a standard PCMCIA digital/analog converter card as an interface and is controlled by a notebook. The developed software is provided with a graphical user interface enabling several animation features. The second, new prototype is designed to display images created by standard CAD applications. It includes the development of a new high speed hardware interface suitable for state-of-the- art fast and high resolution scanning devices, which require high data rates. A true 3D volume display as described will complement the broad range of 3D visualization tools, such as volume rendering packages, stereoscopic and virtual reality techniques, which have become widely available in recent years. Potential applications for the FELIX 3D display include imaging in the field so fair traffic control, medical imaging, computer aided design, science as well as entertainment.

Predictions of Helmet Pad Suspension System Performance using Isolated Pad Impact Results

Science.gov (United States)

2010-09-13

Equation 2 and Equation 3, respectively. 3. METHOD The primary method of data collection for this report is detailed in the 2008 Joint Live Fire ...tests and the helmet system tests (see Figure 3). All testing was performed with a monorail drop tower (see Figure 4) at three conditioning...right) and system test setup (right and center left) Figure 5. MEP monorail drop test setup with a hemispherical impactor (left and center left

Analysis of adjusting effects of mounting force on frequency conversion of mounted nonlinear optics.

Science.gov (United States)

Su, Ruifeng; Liu, Haitao; Liang, Yingchun; Lu, Lihua

2014-01-10

Motivated by the need to increase the second harmonic generation (SHG) efficiency of nonlinear optics with large apertures, a novel mounting configuration with active adjusting function on the SHG efficiency is proposed and mechanically and optically studied. The adjusting effects of the mounting force on the distortion and stress are analyzed by the finite element methods (FEM), as well as the contribution of the distortion and stress to the change in phase mismatch, and the SHG efficiency are theoretically stated. Further on, the SHG efficiency is calculated as a function of the mounting force. The changing trends of the distortion, stress, and the SHG efficiency with the varying mounting force are obtained, and the optimal ones are figured out. Moreover, the mechanism of the occurrence of the optimal values is studied and the adjusting strategy is put forward. Numerical results show the robust adjustment of the mounting force, as well as the effectiveness of the mounting configuration, in increasing the SHG efficiency.

Impact of mandatory motorcycle helmet wearing legislation on head injuries in Viet Nam: results of a preliminary analysis.

Science.gov (United States)

Passmore, Jonathon; Tu, Nguyen Thi Hong; Luong, Mai Anh; Chinh, Nguyen Duc; Nam, Nguyen Phuong

2010-04-01

To compare estimated prevalence of head injuries among road traffic injury patients admitted to hospitals, before and after the introduction of a mandatory helmet law in the Socialist Republic of Viet Nam. Before and after study of all road traffic injury patients with head injuries admitted to 20 provincial and central hospitals 3 months before and after the new law came into effect on 15 December 2007. Relative risk was computed and comparison made for the periods of 3 months before and after the new law. The study found a 16 percent reduction in the risk of road traffic head injuries (4683 to 3522; relative risk [RR] 0.84; 95% confidence interval [CI] 0.81-0.87) and an 18 percent reduction in the risk of road traffic death (deaths in hospital plus injured patients discharged to die at home; 566 to 417; RR 0.82; 95% CI 0.73-0.93). Over the first 3 months of the comprehensive mandatory helmet legislation there has been a significant reduction in the risk of road traffic head injuries among patients admitted to 20 hospitals. The Viet Nam Government's decision to require all motorcycle riders and passengers to wear helmets is suspected of leading to positive road safety benefits and should be seen as a policy example for other low- and middle-income countries with a high utilization of motorcycles for transport.

42 CFR 84.1135 - Half-mask facepieces, full facepieces, hoods, helmets, and mouthpieces; fit; minimum requirements.

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Half-mask facepieces, full facepieces, hoods... Air-Purifying High Efficiency Respirators and Combination Gas Masks § 84.1135 Half-mask facepieces, full facepieces, hoods, helmets, and mouthpieces; fit; minimum requirements. (a) Half-mask facepieces...

42 CFR 84.198 - Half-mask facepieces, full facepieces, mouthpieces, hoods, and helmets; fit; minimum requirements.

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Half-mask facepieces, full facepieces, mouthpieces... APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Chemical Cartridge Respirators § 84.198 Half-mask facepieces, full facepieces, mouthpieces, hoods, and helmets; fit; minimum requirements. (a) Half-mask facepieces...

42 CFR 84.175 - Half-mask facepieces, full facepieces, hoods, helmets, and mouthpieces; fit; minimum requirements.

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Half-mask facepieces, full facepieces, hoods....175 Half-mask facepieces, full facepieces, hoods, helmets, and mouthpieces; fit; minimum requirements. (a) Half-mask facepieces and full facepieces shall be designed and constructed to fit persons with...

The European, Japanese and US protective helmet, gloves and boots for firefighters: thermoregulatory and psychological evaluations.

Science.gov (United States)

Lee, Joo-Young; Yamamoto, Yota; Oe, Riichi; Son, Su-Young; Wakabayashi, Hitoshi; Tochihara, Yutaka

2014-01-01

The purpose of this study was to investigate the physiological and subjective responses of the European, Japanese (JPN) and US firefighters' helmet, gloves and boots for international standardisation. Three experimental conditions were evaluated (clothing mass: 9.4, 8.2 and 10.1 kg for the three conditions, respectively) at the air temperature of 32°C and 60% relative humidity. The results showed that there was no significant difference among the three conditions in oxygen consumption, heart rate, total sweat rate, rectal temperature and mean skin temperature, whereas peripheral temperatures and subjective perceptions were lower in the JPN condition than in the other conditions (P < 0.05). These results indicate that a 0.5-kg reduction in helmet mass and a 1.1-kg reduction in boot mass during exercise resulted in a significant decrease in head and leg temperatures and subjective perceptions, while a 1.9-kg reduction in total clothing mass had insignificant influences on the metabolic burden and overall body temperature.

Mounting for ceramic scroll

Science.gov (United States)

Petty, Jack D.

1993-01-01

A mounting for a ceramic scroll on a metal engine block of a gas turbine engine includes a first ceramic ring and a pair of cross key connections between the first ceramic ring, the ceramic scroll, and the engine block. The cross key connections support the scroll on the engine block independent of relative radial thermal growth and for bodily movement toward an annular mounting shoulder on the engine. The scroll has an uninterrupted annular shoulder facing the mounting shoulder on the engine block. A second ceramic ring is captured between mounting shoulder and the uninterrupted shoulder on the scroll when the latter is bodily shifted toward the mouting shoulder to define a gas seal between the scroll and the engine block.

Solar panel truss mounting systems and methods

Energy Technology Data Exchange (ETDEWEB)

Al-Haddad, Tristan Farris; Cavieres, Andres; Gentry, Russell; Goodman, Joseph; Nolan, Wade; Pitelka, Taylor; Rahimzadeh, Keyan; Brooks, Bradley; Lohr, Joshua; Crooks, Ryan; Porges, Jamie; Rubin, Daniel

2016-06-28

An exemplary embodiment of the present invention provides a solar panel truss mounting system comprising a base and a truss assembly coupled to the base. The truss assembly comprises a first panel rail mount, second panel rail mount parallel to the first panel rail mount, base rail mount parallel to the first and second panel rail mounts, and a plurality of support members. A first portion of the plurality of support members extends between the first and second panel rail mounts. A second portion of the plurality of support members extends between the first panel rail mount and the base rail mount. A third portion of the plurality of support members extends between the second panel rail mount and the base rail mount. The system can further comprise a plurality of connectors for coupling a plurality of photovoltaic solar panels to the truss assembly.

Solar panel truss mounting systems and methods

Energy Technology Data Exchange (ETDEWEB)

Al-Haddad, Tristan Farris; Cavieres, Andres; Gentry, Russell; Goodman, Joseph; Nolan, Wade; Pitelka, Taylor; Rahimzadeh, Keyan; Brooks, Bradley; Lohr, Joshua; Crooks, Ryan; Porges, Jamie; Rubin, Daniel

2018-01-30

An exemplary embodiment of the present invention provides a solar panel truss mounting system comprising a base and a truss assembly coupled to the base. The truss assembly comprises a first panel rail mount, second panel rail mount parallel to the first panel rail mount, base rail mount parallel to the first and second panel rail mounts, and a plurality of support members. A first portion of the plurality of support members extends between the first and second panel rail mounts. A second portion of the plurality of support members extends between the first panel rail mount and the base rail mount. A third portion of the plurality of support members extends between the second panel rail mount and the base rail mount. The system can further comprise a plurality of connectors for coupling a plurality of photovoltaic solar panels to the truss assembly.

Solar panel truss mounting systems and methods

Science.gov (United States)

Al-Haddad, Tristan Farris; Cavieres, Andres; Gentry, Russell; Goodman, Joseph; Nolan, Wade; Pitelka, Taylor; Rahimzadeh, Keyan; Brooks, Bradley; Lohr, Joshua; Crooks, Ryan; Porges, Jamie; Rubin, Daniel

2015-10-20

An exemplary embodiment of the present invention provides a solar panel truss mounting system comprising a base and a truss assembly coupled to the base. The truss assembly comprises a first panel rail mount, second panel rail mount parallel to the first panel rail mount, base rail mount parallel to the first and second panel rail mounts, and a plurality of support members. A first portion of the plurality of support members extends between the first and second panel rail mounts. A second portion of the plurality of support members extends between the first panel rail mount and the base rail mount. A third portion of the plurality of support members extends between the second panel rail mount and the base rail mount. The system can further comprise a plurality of connectors for coupling a plurality of photovoltaic solar panels to the truss assembly.

The head-mounted microscope.

Science.gov (United States)

Chen, Ting; Dailey, Seth H; Naze, Sawyer A; Jiang, Jack J

2012-04-01

Microsurgical equipment has greatly advanced since the inception of the microscope into the operating room. These advancements have allowed for superior surgical precision and better post-operative results. This study focuses on the use of the Leica HM500 head-mounted microscope for the operating phonosurgeon. The head-mounted microscope has an optical zoom from 2× to 9× and provides a working distance from 300 mm to 700 mm. The headpiece, with its articulated eyepieces, adjusts easily to head shape and circumference, and offers a focus function, which is either automatic or manually controlled. We performed five microlaryngoscopic operations utilizing the head-mounted microscope with successful results. By creating a more ergonomically favorable operating posture, a surgeon may be able to obtain greater precision and success in phonomicrosurgery. Phonomicrosurgery requires the precise manipulation of long-handled cantilevered instruments through the narrow bore of a laryngoscope. The head-mounted microscope shortens the working distance compared with a stand microscope, thereby increasing arm stability, which may improve surgical precision. Also, the head-mounted design permits flexibility in head position, enabling operator comfort, and delaying musculoskeletal fatigue. A head-mounted microscope decreases the working distance and provides better ergonomics in laryngoscopic microsurgery. These advances provide the potential to promote precision in phonomicrosurgery. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

Football helmet drop tests on different fields using an instrumented Hybrid III head.

Science.gov (United States)

Viano, David C; Withnall, Chris; Wonnacott, Michael

2012-01-01

An instrumented Hybrid III head was placed in a Schutt ION 4D football helmet and dropped on different turfs to study field types and temperature on head responses. The head was dropped 0.91 and 1.83 m giving impacts of 4.2 and 6.0 m/s on nine different football fields (natural, Astroplay, Fieldturf, or Gameday turfs) at turf temperatures of -2.7 to 23.9 °C. Six repeat tests were conducted for each surface at 0.3 m (1') intervals. The Hybrid III was instrumented with triaxial accelerometers to determine head responses for the different playing surfaces. For the 0.91-m drops, peak head acceleration varied from 63.3 to 117.1 g and HIC(15) from 195 to 478 with the different playing surfaces. The lowest response was with Astroplay, followed by the engineered natural turf. Gameday and Fieldturf involved higher responses. The differences between surfaces decreased in the 1.83 m tests. The cold weather testing involved higher accelerations, HIC(15) and delta V for each surface. The helmet drop test used in this study provides a simple and convenient means of evaluating the compliance and energy absorption of football playing surfaces. The type and temperature of the playing surface influence head responses.

Channel uranium-graphite reactor mounting

International Nuclear Information System (INIS)

Polushkin, K.K.; Kuznetsov, A.G.; Zheleznyakov, B.N.

1981-01-01

According to theoretical principles of general engineering technology the engineering experience of construction-mounting works at the NPP with channel uranium-graphite reactors is systematized. Main parameters and structural features of the 1000 MW channel uranium-graphite reactors are considered. The succession of mounting operations, premounting equipment and pipelines preparation and mounting works technique are described. The most efficient methods of fitting, welding and machining of reactor elements are recommended. Main problems of technical control service are discussed. A typical netted diagram of main equipment of channel uranium-graphite reactors mounting is given

Design and development of a Space Station proximity operations research and development mockup

Science.gov (United States)

Haines, Richard F.

1986-01-01

Proximity operations (Prox-Ops) on-orbit refers to all activities taking place within one km of the Space Station. Designing a Prox-Ops control station calls for a comprehensive systems approach which takes into account structural constraints, orbital dynamics including approach/departure flight paths, myriad human factors and other topics. This paper describes a reconfigurable full-scale mock-up of a Prox-Ops station constructed at Ames incorporating an array of windows (with dynamic star field, target vehicle(s), and head-up symbology), head-down perspective display of manned and unmanned vehicles, voice- actuated 'electronic checklist', computer-generated voice system, expert system (to help diagnose subsystem malfunctions), and other displays and controls. The facility is used for demonstrations of selected Prox-Ops approach scenarios, human factors research (work-load assessment, determining external vision envelope requirements, head-down and head-up symbology design, voice synthesis and recognition research, etc.) and development of engineering design guidelines for future module interiors.

Ocular Tolerance of Contemporary Electronic Display Devices.

Science.gov (United States)

Clark, Andrew J; Yang, Paul; Khaderi, Khizer R; Moshfeghi, Andrew A

2018-05-01

Electronic displays have become an integral part of life in the developed world since the revolution of mobile computing a decade ago. With the release of multiple consumer-grade virtual reality (VR) and augmented reality (AR) products in the past 2 years utilizing head-mounted displays (HMDs), as well as the development of low-cost, smartphone-based HMDs, the ability to intimately interact with electronic screens is greater than ever. VR/AR HMDs also place the display at much closer ocular proximity than traditional electronic devices while also isolating the user from the ambient environment to create a "closed" system between the user's eyes and the display. Whether the increased interaction with these devices places the user's retina at higher risk of damage is currently unclear. Herein, the authors review the discovery of photochemical damage of the retina from visible light as well as summarize relevant clinical and preclinical data regarding the influence of modern display devices on retinal health. Multiple preclinical studies have been performed with modern light-emitting diode technology demonstrating damage to the retina at modest exposure levels, particularly from blue-light wavelengths. Unfortunately, high-quality in-human studies are lacking, and the small clinical investigations performed to date have failed to keep pace with the rapid evolutions in display technology. Clinical investigations assessing the effect of HMDs on human retinal function are also yet to be performed. From the available data, modern consumer electronic displays do not appear to pose any acute risk to vision with average use; however, future studies with well-defined clinical outcomes and illuminance metrics are needed to better understand the long-term risks of cumulative exposure to electronic displays in general and with "closed" VR/AR HMDs in particular. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:346-354.]. Copyright 2018, SLACK Incorporated.

Detector Mount Design for IGRINS

Directory of Open Access Journals (Sweden)

Jae Sok Oh

2014-06-01

Full Text Available The Immersion Grating Infrared Spectrometer (IGRINS is a near-infrared wide-band high-resolution spectrograph jointly developed by the Korea Astronomy and Space Science Institute and the University of Texas at Austin. IGRINS employs three HAWAII-2RG Focal Plane Array (H2RG FPA detectors. We present the design and fabrication of the detector mount for the H2RG detector. The detector mount consists of a detector housing, an ASIC housing, a Field Flattener Lens (FFL mount, and a support base frame. The detector and the ASIC housing should be kept at 65 K and the support base frame at 130 K. Therefore they are thermally isolated by the support made of GFRP material. The detector mount is designed so that it has features of fine adjusting the position of the detector surface in the optical axis and of fine adjusting yaw and pitch angles in order to utilize as an optical system alignment compensator. We optimized the structural stability and thermal characteristics of the mount design using computer-aided 3D modeling and finite element analysis. Based on the structural and thermal analysis, the designed detector mount meets an optical stability tolerance and system thermal requirements. Actual detector mount fabricated based on the design has been installed into the IGRINS cryostat and successfully passed a vacuum test and a cold test.

Mount Athos: Between autonomy and statehood

Directory of Open Access Journals (Sweden)

Avramović Dragutin

2013-01-01

Full Text Available Legal status of the Mount Athos is characterized by many special features that make it internationally unique legal regime. The author analyzes peculiarities of Mount Athos territorial status, legal position of residents and visitors, as well as organization of Mount Athos authorities. The author concludes that the Mount Athos is characterized by a kind of para-sovereignty. Its autonomy involves not only the internal organization, autonomous governance and religious autonomy, but it also includes many elements of secular life of their visitors. Mount Athos has its own, separate legislative, administrative and judicial powers, while the Statute of the Mount Athos has greater legal force than all the other laws of the Greek state, because the state can not unilaterally change its provisions. Having in mind that the wide self-government is vested in church authorities and that the monks have very specific way of living, the author takes a position that the Mount Athos represent 'monastic state', but without statehood. The author also states that the Mount Athos will be faced with many challenges in the context of spreading of an assimilating, universal conception of human rights.

Education, training, and human engineering in aerospace; SAE Aerotech '93, Costa Mesa, CA, Sep. 27-30, 1993

Science.gov (United States)

Shapiro, Diane C. (Editor); Norman, R. Michael (Editor)

1993-01-01

Advances in simulation technology are discussed by a number of government and industry experts, for both training and research and development applications. Advanced techniques, such as helmet-mounted information displays, neurocontrollers, automated training systems, and simulation for space-based systems are included. Advances in training methodology for air transportation are covered by a group of experts in that field, including discussions of advanced flight deck transition training, new training tools, and effective low cost alternatives for part-task training. With the ever-increasing emphasis on human factors in cockpit and cabin design, the section on research, advances, and certification criteria in that field is pertinent. NASA, aircraft manufacturing, and FAA representatives have compiled an informative group of presentations concerning active topics and considerations in human factors design.

Design and Implementation of a Wireless Message Display System

Directory of Open Access Journals (Sweden)

M. U. M. Bakura

2016-08-01

Full Text Available The technology of displaying message is an important part of communication and advertisement. In recent times, Wireless communication has announced its arrival on big stage and the world is going with Smartphone technology. This work describes the design and implementation of a microcontroller based messaging display system. The messaging display system will be interfaced with an android application which will then be used to display information from the comfort of one‘s phone to an LCD screen using the Bluetooth application interface. The work employs the use of an ATMEGA328p Microcontroller mounted on an Arduino board, a Bluetooth Module (HC-06 and an LCD screen. Most of these electronic display systems were using wired cable connections, the Bluetooth technology used in this work is aimed at solving the problem of wired cable connections.The microcontroller provides all the functionality of the display notices and wireless control. A desired text message from a mobile phone is sent via android mobile application to the Bluetooth module located at the receiving end. The Mobile Application was created using online software called App Inventor. When the entire system was connected and tested, it functioned as designed without any noticeable problems. The Bluetooth module responded to commands being sent from the android application appropriately and in a timely manner. The system was able to display 80 characters on the 4 x 20 LCD within the range of 10m as designated by the Bluetooth datasheet.

Simulator scene display evaluation device

Science.gov (United States)

Haines, R. F. (Inventor)

1986-01-01

An apparatus for aligning and calibrating scene displays in an aircraft simulator has a base on which all of the instruments for the aligning and calibrating are mounted. Laser directs beam at double right prism which is attached to pivoting support on base. The pivot point of the prism is located at the design eye point (DEP) of simulator during the aligning and calibrating. The objective lens in the base is movable on a track to follow the laser beam at different angles within the field of vision at the DEP. An eyepiece and a precision diopter are movable into a position behind the prism during the scene evaluation. A photometer or illuminometer is pivotable about the pivot into and out of position behind the eyepiece.

Passive Attenuating Communication Earphone (PACE): Noise Attenuation and Speech Intelligibility Performance When Worn in Conjunction with the HGU-56/P and HGU-55/P Flight Helmets

Science.gov (United States)

2013-10-16

right) eartips The purpose of this study was to integrate the HGU-56/P and HGU-55/P flight helmets with PACE to measure the noise attenuation and...55/P flight helmet integrated with PACE 2.0 METHODS 2.1 Subjects Twenty paid volunteer subjects (9 male, 11 female) participated in the study ...Pan Pad Pat Path Pack Pass Buff Bus But Bug Buck Bun Sat Sag Sass Sack Sad Sap Run Sun Bun Gun Fun Nun 8 Distribution A: Approved for

Display device for technical processes, particularly in control rooms of nuclear power stations

International Nuclear Information System (INIS)

Aleite, W.

1982-01-01

Measuring equipment for displaying pictures of process parameters is used as the display device for technical processes. There are also visual indicators mounted next to each other to reproduce process parameters using a computer. According to the invention, a large number of visual indicators are supplied via a picture repeat computer and a multicomputer picture generating system in a redundancy circuit, which makes it possible to produce a coherent representation of process parameters via several visual indicators situated next to each other. The invention is particularly suitable for assessing developments over a time period in the control rooms of nuclear powerstations. (orig.) [de

Flush Mounting Of Thin-Film Sensors

Science.gov (United States)

Moore, Thomas C., Sr.

1992-01-01

Technique developed for mounting thin-film sensors flush with surfaces like aerodynamic surfaces of aircraft, which often have compound curvatures. Sensor mounted in recess by use of vacuum pad and materials selected for specific application. Technique involves use of materials tailored to thermal properties of substrate in which sensor mounted. Together with customized materials, enables flush mounting of thin-film sensors in most situations in which recesses for sensors provided. Useful in both aircraft and automotive industries.

Object-Based Attention and Cognitive Tunneling

Science.gov (United States)

Jarmasz, Jerzy; Herdman, Chris M.; Johannsdottir, Kamilla Run

2005-01-01

Simulator-based research has shown that pilots cognitively tunnel their attention on head-up displays (HUDs). Cognitive tunneling has been linked to object-based visual attention on the assumption that HUD symbology is perceptually grouped into an object that is perceived and attended separately from the external scene. The present research…

Designing safer composite helmets to reduce rotational accelerations during oblique impacts.

Science.gov (United States)

Mosleh, Yasmine; Cajka, Martin; Depreitere, Bart; Vander Sloten, Jos; Ivens, Jan

2018-05-01

Oblique impact is the most common accident situation that occupants in traffic accidents or athletes in professional sports experience. During oblique impact, the human head is subjected to a combination of linear and rotational accelerations. Rotational movement is known to be responsible for traumatic brain injuries. In this article, composite foam with a column/matrix composite configuration is proposed for head protection applications to replace single-layer uniform foam, to better attenuate rotational movement of the head during oblique impacts. The ability of composite foam in the mitigation of rotational head movement is studied by performing finite element (FE) simulations of oblique impact on flat and helmet shape specimens. The performance of composite foam with respect to parameters such as compliance of the matrix foam and the number, size and cross-sectional shape of the foam columns is explored in detail, and subsequently an optimized structure is proposed. The simulation results show that using composite foam instead of single-layer foam, the rotational acceleration and velocity of the headform can be significantly reduced. The parametric study indicates that using a more compliant matrix foam and by increasing the number of columns in the composite foam configuration, the rotation can be further mitigated. This was confirmed by experimental results. The simulation results were also analyzed based on global head injury criteria such as head injury criterion, rotational injury criterion, brain injury criterion and generalized acceleration model for brain injury threshold which further confirmed the superior performance of composite foam versus single-layer homogeneous expanded polystyrene foam. The findings of simulations give invaluable information for design of protective helmets or, for instance, headliners for the automotive industry.

Characterization of Engine Mount Elastomers

National Research Council Canada - National Science Library

Szabo, Jeffrey P

2005-01-01

As part of a project to develop methods for modelling the performance of engine mounts, several oil resistant alternative materials were prepared, and compared to conventional materials from mounts...

A Vehicle-mounted Crop Detector with Wireless Sensor Network

Directory of Open Access Journals (Sweden)

Zhenjiang ZHONG

2014-03-01

Full Text Available In order to detect crop chlorophyll content in real-time, a new vehicle-mounted detector for measuring crop canopy spectral characteristics was developed. It was designed to work as a wireless sensor network with several optical sensor nodes and one control unit. All the optical sensor nodes were mounted on an on-board mechanical structure so that they could collect the canopy spectral data while in mobile condition. Each optical sensor node was designed to contain four optical channels, which allowed it work at the wavebands of 550, 650, 766 and 850 nm. The control unit included a PDA (Personal Digital Assistant device with a ZigBee wireless network coordinator and a GPRS module. It was used to receive, display, store all the data sent from optical sensor nodes and send data to the server through GPRS module. The calibration tests verified the stability of the wireless network and the measurement precision of the sensors. Both stationary and moving field experiments were also conducted in a winter wheat experimental field. Results showed that the correlation between chlorophyll content and vegetation index had high significance with the highest R2 of 0.6824. Those results showed the potential of the detector for field application.

Head-motion-controlled video goggles: preliminary concept for an interactive laparoscopic image display (i-LID).

Science.gov (United States)

Aidlen, Jeremy T; Glick, Sara; Silverman, Kenneth; Silverman, Harvey F; Luks, Francois I

2009-08-01

Light-weight, low-profile, and high-resolution head-mounted displays (HMDs) now allow personalized viewing, of a laparoscopic image. The advantages include unobstructed viewing, regardless of position at the operating table, and the possibility to customize the image (i.e., enhanced reality, picture-in-picture, etc.). The bright image display allows use in daylight surroundings and the low profile of the HMD provides adequate peripheral vision. Theoretic disadvantages include reliance for all on the same image capture and anticues (i.e., reality disconnect) when the projected image remains static, despite changes in head position. This can lead to discomfort and even nausea. We have developed a prototype of interactive laparoscopic image display that allows hands-free control of the displayed image by changes in spatial orientation of the operator's head. The prototype consists of an HMD, a spatial orientation device, and computer software to enable hands-free panning and zooming of a video-endoscopic image display. The spatial orientation device uses magnetic fields created by a transmitter and receiver, each containing three orthogonal coils. The transmitter coils are efficiently driven, using USB power only, by a newly developed circuit, each at a unique frequency. The HMD-mounted receiver system links to a commercially available PC-interface PCI-bus sound card (M-Audiocard Delta 44; Avid Technology, Tewksbury, MA). Analog signals at the receiver are filtered, amplified, and converted to digital signals, which are processed to control the image display. The prototype uses a proprietary static fish-eye lens and software for the distortion-free reconstitution of any portion of the captured image. Left-right and up-down motions of the head (and HMD) produce real-time panning of the displayed image. Motion of the head toward, or away from, the transmitter causes real-time zooming in or out, respectively, of the displayed image. This prototype of the interactive HMD

Joint Service Aircrew Mask (JSAM) - Tactical Aircraft (TA) A/P22P-14A Respirator Assembly (V)5: Speech Intelligibility Performance with Double Hearing Protection, HGU-84/P Flight Helmet

Science.gov (United States)

2017-04-06

data does not license the holder or any other person or corporation; or convey any rights or permission to manufacture , use, or sell any patented...airworthiness. The JSAM-TA Respirator Assembly (V)5 (Figure 2) is a chemical, biological, and radiological respirator assembly manufactured by Cam Lock...Classic™ sizing matrix for speech intelligibility Subject ID# Gender HGU- 84/P Helmet Helmet Liner (inches) Earcup Spacers (centered behind

System for recording and displaying two-phase flow topographies

International Nuclear Information System (INIS)

Cary, C.N.; Block, J.A.

1979-01-01

A system of hardware and software has been developed and used to record and display in various forms details of the countercurrent flow topographies occurring in a scaled Pressurized Water Reactor downcomer annulus. An array of 288 conductivity sensors was mounted in a 1/15 scale PWR annulus. At each moment in time, the state of each probe indicates the presence or absence of water in this immediate vicinity. An electronic data acquisition system records the states of all probes 108 times per second on magnetic tape; software routines retrieve the data and reconstruct visual analogs of the flow topographies. The instantaneous two-phase state of the annulus at each instant can be displayed on a hard copy plotter or on a CRT screen. By synchronizing a camera drive with the CRT display, 16mm films have been made recreating the flow process at full speed and at various slow motion rates. All data obtained are stored in computer files in numerical form and can be subjected to various types of quantitative analysis to assist in advanced code development and verification

Solar panel parallel mounting configuration

Science.gov (United States)

Mutschler, Jr., Edward Charles (Inventor)

1998-01-01

A spacecraft includes a plurality of solar panels interconnected with a power coupler and an electrically operated device to provide power to the device when the solar cells are insolated. The solar panels are subject to bending distortion when entering or leaving eclipse. Spacecraft attitude disturbances are reduced by mounting each of the solar panels to an elongated boom made from a material with a low coefficient of thermal expansion, so that the bending of one panel is not communicated to the next. The boom may be insulated to reduce its bending during changes in insolation. A particularly advantageous embodiment mounts each panel to the boom with a single mounting, which may be a hinge. The single mounting prevents transfer of bending moments from the panel to the boom.

Mounting Thin Samples For Electrical Measurements

Science.gov (United States)

Matus, L. G.; Summers, R. L.

1988-01-01

New method for mounting thin sample for electrical measurements involves use of vacuum chuck to hold a ceramic mounting plate, which holds sample. Contacts on mounting plate establish electrical connection to sample. Used to make electrical measurements over temperature range from 77 to 1,000 K and does not introduce distortions into magnetic field during Hall measurements.

Additional helmet and pack loading reduce situational awareness during the establishment of marksmanship posture.

Science.gov (United States)

Lim, Jongil; Palmer, Christopher J; Busa, Michael A; Amado, Avelino; Rosado, Luis D; Ducharme, Scott W; Simon, Darnell; Van Emmerik, Richard E A

2017-06-01

The pickup of visual information is critical for controlling movement and maintaining situational awareness in dangerous situations. Altered coordination while wearing protective equipment may impact the likelihood of injury or death. This investigation examined the consequences of load magnitude and distribution on situational awareness, segmental coordination and head gaze in several protective equipment ensembles. Twelve soldiers stepped down onto force plates and were instructed to quickly and accurately identify visual information while establishing marksmanship posture in protective equipment. Time to discriminate visual information was extended when additional pack and helmet loads were added, with the small increase in helmet load having the largest effect. Greater head-leading and in-phase trunk-head coordination were found with lighter pack loads, while trunk-leading coordination increased and head gaze dynamics were more disrupted in heavier pack loads. Additional armour load in the vest had no consequences for Time to discriminate, coordination or head dynamics. This suggests that the addition of head borne load be carefully considered when integrating new technology and that up-armouring does not necessarily have negative consequences for marksmanship performance. Practitioner Summary: Understanding the trade-space between protection and reductions in task performance continue to challenge those developing personal protective equipment. These methods provide an approach that can help optimise equipment design and loading techniques by quantifying changes in task performance and the emergent coordination dynamics that underlie that performance.

Computer-enhanced stereoscopic vision in a head-mounted operating binocular

International Nuclear Information System (INIS)

Birkfellner, Wolfgang; Figl, Michael; Matula, Christian; Hummel, Johann; Hanel, Rudolf; Imhof, Herwig; Wanschitz, Felix; Wagner, Arne; Watzinger, Franz; Bergmann, Helmar

2003-01-01

Based on the Varioscope, a commercially available head-mounted operating binocular, we have developed the Varioscope AR, a see through head-mounted display (HMD) for augmented reality visualization that seamlessly fits into the infrastructure of a surgical navigation system. We have assessed the extent to which stereoscopic visualization improves target localization in computer-aided surgery in a phantom study. In order to quantify the depth perception of a user aiming at a given target, we have designed a phantom simulating typical clinical situations in skull base surgery. Sixteen steel spheres were fixed at the base of a bony skull, and several typical craniotomies were applied. After having taken CT scans, the skull was filled with opaque jelly in order to simulate brain tissue. The positions of the spheres were registered using VISIT, a system for computer-aided surgical navigation. Then attempts were made to locate the steel spheres with a bayonet probe through the craniotomies using VISIT and the Varioscope AR as a stereoscopic display device. Localization of targets 4 mm in diameter using stereoscopic vision and additional visual cues indicating target proximity had a success rate (defined as a first-trial hit rate) of 87.5%. Using monoscopic vision and target proximity indication, the success rate was found to be 66.6%. Omission of visual hints on reaching a target yielded a success rate of 79.2% in the stereo case and 56.25% with monoscopic vision. Time requirements for localizing all 16 targets ranged from 7.5 min (stereo, with proximity cues) to 10 min (mono, without proximity cues). Navigation error is primarily governed by the accuracy of registration in the navigation system, whereas the HMD does not appear to influence localization significantly. We conclude that stereo vision is a valuable tool in augmented reality guided interventions. (note)

Cost Analysis of Noninvasive Helmet Ventilation Compared with Use of Noninvasive Face Mask in ARDS

Directory of Open Access Journals (Sweden)

Kwadwo Kyeremanteng

2018-01-01

Full Text Available Intensive care unit (ICU costs have doubled since 2000, totalling 108 billion dollars per year. Acute respiratory distress syndrome (ARDS has a prevalence of 10.4% and a 28-day mortality of 34.8%. Noninvasive ventilation (NIV is used in up to 30% of cases. A recent randomized controlled trial by Patel et al. (2016 showed lower intubation rates and 90-day mortality when comparing helmet to face mask NIV in ARDS. The population in the Patel et al. trial was used for cost analysis in this study. Projections of cost savings showed a decrease in ICU costs by $2527 and hospital costs by $3103 per patient, along with a 43.3% absolute reduction in intubation rates. Sensitivity analysis showed consistent cost reductions. Projected annual cost savings, assuming the current prevalence of ARDS, were $237538 in ICU costs and $291682 in hospital costs. At a national level, using yearly incidence of ARDS cases in American ICUs, this represents $449 million in savings. Helmet NIV, compared to face mask NIV, in nonintubated patients with ARDS, reduces ICU and hospital direct-variable costs along with intubation rates, LOS, and mortality. A large-scale cost-effectiveness analysis is needed to validate the findings.

Resilient mounting systems in buildings

NARCIS (Netherlands)

Breeuwer, R.; Tukker, J.C.

1976-01-01

The basic elements of resilient mounting systems are described and various measures for quantifying the effect of such systems defined. Using electrical analogue circuits, the calculation of these measures is illustrated. With special reference to resilient mounting systems in buildings, under

Low-Thermal-Resistance Baseplate Mounting

Science.gov (United States)

Perreault, W. T.

1984-01-01

Low-thermal-resistance mounting achieved by preloading baseplate to slight convexity with screws threaded through beam. As mounting bolts around edge of base-place tightened, baseplate and cold plate contact first in center, with region of intimate contact spreading outward as bolts tightened.

An improved loopless mounting method for cryocrystallography

International Nuclear Information System (INIS)

Jian-Xun, Qi; Fan, Jiang

2010-01-01

Based on a recent loopless mounting method, a simplified loopless and bufferless crystal mounting method is developed for macromolecular crystallography. This simplified crystal mounting system is composed of the following components: a home-made glass capillary, a brass seat for holding the glass capillary, a flow regulator, and a vacuum pump for evacuation. Compared with the currently prevalent loop mounting method, this simplified method has almost the same mounting procedure and thus is compatible with the current automated crystal mounting system. The advantages of this method include higher signal-to-noise ratio, more accurate measurement, more rapid flash cooling, less x-ray absorption and thus less radiation damage to the crystal. This method can be extended to the flash-freeing of a crystal without or with soaking it in a lower concentration of cryoprotectant, thus it may be the best option for data collection in the absence of suitable cryoprotectant. Therefore, it is suggested that this mounting method should be further improved and extensively applied to cryocrystallographic experiments. (general)

An improved loopless mounting method for cryocrystallography

Science.gov (United States)

Qi, Jian-Xun; Jiang, Fan

2010-01-01

Based on a recent loopless mounting method, a simplified loopless and bufferless crystal mounting method is developed for macromolecular crystallography. This simplified crystal mounting system is composed of the following components: a home-made glass capillary, a brass seat for holding the glass capillary, a flow regulator, and a vacuum pump for evacuation. Compared with the currently prevalent loop mounting method, this simplified method has almost the same mounting procedure and thus is compatible with the current automated crystal mounting system. The advantages of this method include higher signal-to-noise ratio, more accurate measurement, more rapid flash cooling, less x-ray absorption and thus less radiation damage to the crystal. This method can be extended to the flash-freeing of a crystal without or with soaking it in a lower concentration of cryoprotectant, thus it may be the best option for data collection in the absence of suitable cryoprotectant. Therefore, it is suggested that this mounting method should be further improved and extensively applied to cryocrystallographic experiments.

Building the Traffic, Navigation, and Situation Awareness System (T-NASA) for Surface Operations

Science.gov (United States)

McCann, Robert S.

1996-01-01

We report the results of a part-task simulation evaluating the separate and combined effects of an electronic moving map display and newly developed HUD symbology on ground taxi performance, under moderate- and low-visibility conditions. Twenty-four commercial airline pilots carried out a series of 28 gate-to-runway taxi trials at Chicago O'Hare. Half of the trials were conducted under moderate visibility (RVR 1400 ft), and half under low visibility (RVR 700 ft). In the baseline condition, where navigation support was limited to surface features and a Jeppesen paper map, navigation errors were committed on almost half of the trials. These errors were virtually abolished when the electronic moving map or the HUD symbology was available; in addition, compare, the baseline condition, both forms of navigation aid yielded an increase in forward taxi speed. The speed increase was greater for HUD than the electronic moving map, and greater under low visibility than under moderate visibility. These results suggest that combination of electronic moving map and HUD symbology has the potential to greatly increase the efficiency of ground operations, particularly under low-visibility conditions.

A Statistical Approach to Continuous Self-Calibrating Eye Gaze Tracking for Head-Mounted Virtual Reality Systems

OpenAIRE

Tripathi, Subarna; Guenter, Brian

2016-01-01

We present a novel, automatic eye gaze tracking scheme inspired by smooth pursuit eye motion while playing mobile games or watching virtual reality contents. Our algorithm continuously calibrates an eye tracking system for a head mounted display. This eliminates the need for an explicit calibration step and automatically compensates for small movements of the headset with respect to the head. The algorithm finds correspondences between corneal motion and screen space motion, and uses these to...

Multi-Mounted X-Ray Computed Tomography.

Science.gov (United States)

Fu, Jian; Liu, Zhenzhong; Wang, Jingzheng

2016-01-01

Most existing X-ray computed tomography (CT) techniques work in single-mounted mode and need to scan the inspected objects one by one. It is time-consuming and not acceptable for the inspection in a large scale. In this paper, we report a multi-mounted CT method and its first engineering implementation. It consists of a multi-mounted scanning geometry and the corresponding algebraic iterative reconstruction algorithm. This approach permits the CT rotation scanning of multiple objects simultaneously without the increase of penetration thickness and the signal crosstalk. Compared with the conventional single-mounted methods, it has the potential to improve the imaging efficiency and suppress the artifacts from the beam hardening and the scatter. This work comprises a numerical study of the method and its experimental verification using a dataset measured with a developed multi-mounted X-ray CT prototype system. We believe that this technique is of particular interest for pushing the engineering applications of X-ray CT.

Housing And Mounting Structure

Science.gov (United States)

Anderson, Gene R.; Armendariz, Marcelino G.; Baca, Johnny R.F.; Bryan, Robert P.; Carson, Richard F.; Duckett, III, Edwin B.; McCormick, Frederick B.; Miller, Gregory V.; Peterson, David W.; Smith, Terrance T.

2005-03-08

This invention relates to an optical transmitter, receiver or transceiver module, and more particularly, to an apparatus for connecting a first optical connector to a second optical connector. The apparatus comprises: (1) a housing having at least a first end and at least a second end, the first end of the housing capable of receiving the first optical connector, and the second end of the housing capable of receiving the second optical connector; (2) a longitudinal cavity extending from the first end of the housing to the second end of the housing; and (3) an electromagnetic shield comprising at least a portion of the housing. This invention also relates to an apparatus for housing a flexible printed circuit board, and this apparatus comprises: (1) a mounting structure having at least a first surface and a second surface; (2) alignment ridges along the first and second surfaces of the mounting structure, the alignment ridges functioning to align and secure a flexible printed circuit board that is wrapped around and attached to the first and second surfaces of the mounting structure; and (3) a series of heat sink ridges adapted to the mounting structure, the heat sink ridges functioning to dissipate heat that is generated from the flexible printed circuit board.

PECULIARITIES OF ASSIGNMENT OF ROLLING BEARING MOUNTING AND PARAMETERS OF GEOMETRIC ACCURACY OF MOUNTING SURFACES OF SHAFTS AND FRAMES

Directory of Open Access Journals (Sweden)

Adamenko Yu. І.

2017-04-01

Full Text Available The standards and methods concerning assignment of rolling bearing fit with shafts and frames via example of bearing 6-208 are analyzed. We set certain differences of recommendations according to GOST 3325-85, "Rolling bearings. Tolerance zones and technical requirements to mounting surfaces of shafts and frames. Attachment" and by reference of rolling bearing manufacturers. The following factors should be taken into consideration when assigning the mounting with the tension the internal ring of the bearing with shaft and mounting with a gap in the outer ring with a housing bore. The methods of achieving accuracy of mounting surfaces of shafts and frames via form tolerance assignment: roundness tolerance, profile of longitudinal cut, cross section, cylindricity and others. It is possible to limit the bearing rings in different ways, for example appointing the cylindrical mounting surfaces and bead end surfaces the appropriate tolerances, namely: coaxiality tolerance or full radial beat of mounting surfaces, and also perpendicularity tolerance, butt beats and full butt beats of mounting end surfaces. We suggest to expand methods of achieving the accuracy of shafts and frames depending on seriation of production and production operations metrology support.

Acceleration-based methodology to assess the blast mitigation performance of explosive ordnance disposal helmets

Science.gov (United States)

Dionne, J. P.; Levine, J.; Makris, A.

2018-01-01

To design the next generation of blast mitigation helmets that offer increasing levels of protection against explosive devices, manufacturers must be able to rely on appropriate test methodologies and human surrogates that will differentiate the performance level of various helmet solutions and ensure user safety. Ideally, such test methodologies and associated injury thresholds should be based on widely accepted injury criteria relevant within the context of blast. Unfortunately, even though significant research has taken place over the last decade in the area of blast neurotrauma, there currently exists no agreement in terms of injury mechanisms for blast-induced traumatic brain injury. In absence of such widely accepted test methods and injury criteria, the current study presents a specific blast test methodology focusing on explosive ordnance disposal protective equipment, involving the readily available Hybrid III mannequin, initially developed for the automotive industry. The unlikely applicability of the associated brain injury criteria (based on both linear and rotational head acceleration) is discussed in the context of blast. Test results encompassing a large number of blast configurations and personal protective equipment are presented, emphasizing the possibility to develop useful correlations between blast parameters, such as the scaled distance, and mannequin engineering measurements (head acceleration). Suggestions are put forward for a practical standardized blast testing methodology taking into account limitations in the applicability of acceleration-based injury criteria as well as the inherent variability in blast testing results.

Design and prototype of an augmented reality display with per-pixel mutual occlusion capability.

Science.gov (United States)

Wilson, Austin; Hua, Hong

2017-11-27

State-of-the-art optical see-through head-mounted displays for augmented reality (AR) applications lack mutual occlusion capability, which refers to the ability to render correct light blocking relationship when merging digital and physical objects, such that the virtual views appear to be ghost-like and lack realistic appearance. In this paper, using off-the-shelf optical components, we present the design and prototype of an AR display which is capable of rendering per-pixel mutual occlusion. Our prototype utilizes a miniature organic light emitting display coupled with a liquid crystal on silicon type spatial light modulator to achieve an occlusion capable AR display offering a 30° diagonal field of view and an angular resolution of 1.24 arcminutes, with an optical performance of > 0.4 contrast over the full field at the Nquist frequency of 24.2 cycles/degree. We experimentally demonstrate a monocular prototype achieving >100:1 dynamic range in well-lighted environments.

Mounting support for a photovoltaic module

Science.gov (United States)

Brandt, Gregory Michael; Barsun, Stephan K.; Coleman, Nathaniel T.; Zhou, Yin

2013-03-26

A mounting support for a photovoltaic module is described. The mounting support includes a foundation having an integrated wire-way ledge portion. A photovoltaic module support mechanism is coupled with the foundation.

Systems and methods for mirror mounting with minimized distortion

Science.gov (United States)

Antonille, Scott R. (Inventor); Wallace, Thomas E. (Inventor); Content, David A. (Inventor); Wake, Shane W. (Inventor)

2012-01-01

A method for mounting a mirror for use in a telescope includes attaching the mirror to a plurality of adjustable mounts; determining a distortion in the mirror caused by the plurality adjustable mounts, and, if the distortion is determined to be above a predetermined level: adjusting one or more of the adjustable mounts; and determining the distortion in the mirror caused by the adjustable mounts; and in the event the determined distortion is determined to be at or below the predetermined level, rigidizing the adjustable mounts.

Technical preparation of the Yuzhteploehnergomontazh trust for technological equipment mounting

International Nuclear Information System (INIS)

Zayats, A.I.

1982-01-01

Measures of technical preparation for equipment mounting at the Zaporozhe NPP developed with the Yuzhteploehnergomontazh trust experts are considered. These measures envisage the construction of mounting base of heat facilities, calculation of labour contents and determination of necessary quantity of mounters, development of optimal flowsheet of mounting control, improvement of mounting qualification and creation of stable collective body, improvement of technical level of mounting and welding works, organizational-technical measures on mounting logistics. Factors affecting negatively technical preparation quality of equipment mounting at the Zaporozhe NPP are discussed. The flowsheet of mounting control is presented

Design Integration of Man-Machine Interface (MMI) Display Drawings and MMI Database

Energy Technology Data Exchange (ETDEWEB)

Kim, Yong Jun; Seo, Kwang Rak; Song, Jeong Woog; Kim, Dae Ho; Han, Jung A [KEPCO Engineering and Construction Co., Deajeon (Korea, Republic of)

2016-10-15

The conventional Main Control Room (MCR) was designed using hardwired controllers and analog indications mounted on control boards for control and acquisition of plant information. This is compared with advanced MCR design where Flat Panel Displays (FPDs) with soft controls and mimic displays are used. The advanced design needs MMI display drawings replacing the conventional control board layout drawings and component lists. The data is linked to related object of the MMI displays. Compilation of the data into the DB is generally done manually, which tends to introduce errors and discrepancies. Also, updating and managing is difficult due to a huge number of entries in the DB and the update must closely track the changes in the associated drawing. Therefore, automating the DB update whenever a related drawing is updated would be quite beneficial. An attempt is made to develop a new method to integrate the MMIS display drawing design and the DB management. This would significantly reduce the amount of errors and improve design quality. The design integration of the MMI Display drawing and MMI DB is explained briefly but concisely in this paper. The existing method involved individually and separately inputting design data for the MMI display drawings. This caused to the potential problem of data discrepancies and errors as well as the update time lag between related drawings and the DB. This led to development of an integration of design process which automates the design data input activity.

Human-Robot Interaction Directed Research Project

Science.gov (United States)

Sandor, Aniko; Cross, Ernest V., II; Chang, Mai Lee

2014-01-01

Human-robot interaction (HRI) is a discipline investigating the factors affecting the interactions between humans and robots. It is important to evaluate how the design of interfaces and command modalities affect the human's ability to perform tasks accurately, efficiently, and effectively when working with a robot. By understanding the effects of interface design on human performance, workload, and situation awareness, interfaces can be developed to appropriately support the human in performing tasks with minimal errors and with appropriate interaction time and effort. Thus, the results of research on human-robot interfaces have direct implications for the design of robotic systems. This DRP concentrates on three areas associated with interfaces and command modalities in HRI which are applicable to NASA robot systems: 1) Video Overlays, 2) Camera Views, and 3) Command Modalities. The first study focused on video overlays that investigated how Augmented Reality (AR) symbology can be added to the human-robot interface to improve teleoperation performance. Three types of AR symbology were explored in this study, command guidance (CG), situation guidance (SG), and both (SCG). CG symbology gives operators explicit instructions on what commands to input, whereas SG symbology gives operators implicit cues so that operators can infer the input commands. The combination of CG and SG provided operators with explicit and implicit cues allowing the operator to choose which symbology to utilize. The objective of the study was to understand how AR symbology affects the human operator's ability to align a robot arm to a target using a flight stick and the ability to allocate attention between the symbology and external views of the world. The study evaluated the effects type of symbology (CG and SG) has on operator tasks performance and attention allocation during teleoperation of a robot arm. The second study expanded on the first study by evaluating the effects of the type of

Mounting and Alignment of IXO Mirror Segments

Science.gov (United States)

Chan, Kai-Wing; Zhang, William; Evans, Tyler; McClelland, Ryan; Hong, Melinda; Mazzarella, James; Saha, Timo; Jalota, Lalit; Olsen, Lawrence; Byron, Glenn

2010-01-01

A suspension-mounting scheme is developed for the IXO (International X-ray Observatory) mirror segments in which the figure of the mirror segment is preserved in each stage of mounting. The mirror, first fixed on a thermally compatible strongback, is subsequently transported, aligned and transferred onto its mirror housing. In this paper, we shall outline the requirement, approaches, and recent progress of the suspension mount processes.

14 CFR 33.23 - Engine mounting attachments and structure.

Science.gov (United States)

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine mounting attachments and structure... mounting attachments and structure. (a) The maximum allowable limit and ultimate loads for engine mounting attachments and related engine structure must be specified. (b) The engine mounting attachments and related...

76 FR 76689 - Cibola National Forest, Mount Taylor Ranger District, NM, Mount Taylor Combined Exploratory Drilling

Science.gov (United States)

2011-12-08

... National Forest, Mount Taylor Ranger District, NM, Mount Taylor Combined Exploratory Drilling AGENCY... proposed action is to approve two Plans of Operations for exploratory uranium drilling on the Cibola... San Mateo. In total, there are up to 279 drill holes that would be drilled over a period not to exceed...

Mounting apparatus for a nozzle guide vane assembly

Science.gov (United States)

Boyd, Gary L.; Shaffer, James E.

1995-01-01

The present invention provides a ceramic nozzle guide assembly with an apparatus for mounting it to a metal nozzle case that includes an intermediate ceramic mounting ring. The mounting ring includes a plurality of projections that are received within a plurality of receptacles formed in the nozzle case. The projections of the mounting ring are secured within the receptacles by a ceramic retainer that allows contact between the two components only along arcuate surfaces thus eliminating sliding contact between the components.

Three-dimensional visualization and display technologies; Proceedings of the Meeting, Los Angeles, CA, Jan. 18-20, 1989

International Nuclear Information System (INIS)

Robbins, W.E.; Fisher, S.S.

1989-01-01

Special attention was given to problems of stereoscopic display devices, such as CAD for enhancement of the design process in visual arts, stereo-TV improvement of remote manipulator performance, a voice-controlled stereographic video camera system, and head-mounted displays and their low-cost design alternatives. Also discussed was a novel approach to chromostereoscopic microscopy, computer-generated barrier-strip autostereography and lenticular stereograms, and parallax barrier three-dimensional TV. Additional topics include processing and user interface isssues and visualization applications, including automated analysis and fliud flow topology, optical tomographic measusrements of mixing fluids, visualization of complex data, visualization environments, and visualization management systems

Mounting clips for panel installation

Science.gov (United States)

Cavieres, Andres; Al-Haddad, Tristan; Goodman, Joseph

2017-07-11

A photovoltaic panel mounting clip comprising a base, central indexing tabs, flanges, lateral indexing tabs, and vertical indexing tabs. The mounting clip removably attaches one or more panels to a beam or the like structure, both mechanically and electrically. It provides secure locking of the panels in all directions, while providing guidance in all directions for accurate installation of the panels to the beam or the like structure.

49 CFR 179.10 - Tank mounting.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Tank mounting. 179.10 Section 179.10 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY... Design Requirements § 179.10 Tank mounting. (a) The manner in which tanks are attached to the car...

Ocean floor mounting of wave energy converters

Science.gov (United States)

Siegel, Stefan G

2015-01-20

A system for mounting a set of wave energy converters in the ocean includes a pole attached to a floor of an ocean and a slider mounted on the pole in a manner that permits the slider to move vertically along the pole and rotate about the pole. The wave energy converters can then be mounted on the slider to allow adjustment of the depth and orientation of the wave energy converters.

Three-dimensional system integration for HUD placement on a new tactical airlift platform: design eye point vs. HUD eye box with accommodation and perceptual implications

Science.gov (United States)

Harbour, Steven D.; Hudson, Jeffery A.; Zehner, Gregory F.

2012-06-01

The retrofitting of a cockpit with a Head-Up-Display (HUD) raises potential accommodation and perceptual issues for pilots that must be addressed. For maximum optical efficiency, the goal is to be able to place every pilot's eye into the HUD Eye Motion Box (EMB) given a seat adjustment range. Initially, the Eye Reference Point (ERP) of the EMB should theoretically be located on the aircraft's original cockpit Design Eye Point (DEP), but human postures vary, and HUD systems may not be optimally placed. In reality, there is a distribution of pilot eyes around the DEP (which is dominant eye dependent); therefore, this must be accounted for in order to obtain appropriate visibility of all of the symbology based on photonic characteristics of the HUD. Pilot size and postural variation need to be taken into consideration when positioning the HUD system to ensure proper vision of all HUD symbology in addition to meeting the basic physical accommodation requirements of the cockpit. The innovative process and data collection methods for maximizing accommodation and pilot perception on a new "tactical airlift" platform are discussed as well as the related neurocognitive factors and the effects of information display design on cognitive phenomena.

"Split Cast Mounting: Review and New Technique".

Science.gov (United States)

Gundawar, S M; Pande, Neelam A; Jaiswal, Priti; Radke, U M

2014-12-01

For the fabrication of a prosthesis, the Prosthodontist meticulously performs all the steps. The laboratory technician then make every effort/strives to perform the remaining lab procedures. However when the processed dentures are remounted on the articulator, some changes are seen. These changes may be divided into two categories: Pre-insertion and post-insertion changes, which deal with the physical properties of the materials involved (Parker, J Prosthet Dent 31:335-342, 1974). Split cast mounting is the method of mounting casts on the articulator. It is essentially a maxillary cast constructed in two parts with a horizontal division. The procedure allows for the verification of the accuracy of the initial mounting and the ease of removal and replacement of the cast. This provides a precise means of correcting the changes in occlusion occurring as a result of the processing technique (Nogueira et al., J Prosthet Dent 91:386-388, 2004). Instability of the split mounting has always been a problem to the Prosthodontist thereby limiting its use. There are various materials mentioned in the literature. The new technique by using Dowel pins and twill thread is very easy, cheaper and simple way to stabilize the split mounting. It is useful and easy in day to day laboratory procedures. The article presents different methods of split cast mounting and the new procedure using easily available materials in prosthetic laboratory.

Restocking the optical designers' toolbox for next-generation wearable displays (Presentation Recording)

Science.gov (United States)

Kress, Bernard C.

2015-09-01

Three years ago, industry and consumers learned that there was more to Head Mounted Displays (HMDs) than the long-lasting but steady market for defense or the market for gadget video player headsets: the first versions of Smart Glasses were introduced to the public. Since then, most major consumer electronics companies unveiled their own versions of Connected Glasses, Smart Glasses or Smart Eyewear, AR (Augmented Reality) and VR (Virtual Reality) headsets. This rush resulted in the build-up of a formidable zoo of optical technologies, each claiming to be best suited for the task on hand. Today, the question is not so much anymore "will the Smart Glass market happen?" but rather "which optical technologies will be best fitted for the various declinations of the existing wearable display market," one of the main declination being the Smart Glasses market.

Research on LQR optimal control method of active engine mount

Science.gov (United States)

Huan, Xie; Yu, Duan

2018-04-01

In this paper, the LQR control method is applied to the active mount of the engine, and a six-cylinder engine excitation model is established. Through the joint simulation of AMESim and MATLAB, the vibration isolation performance of the active mount system and the passive mount system is analyzed. Excited by the multi-engine operation, the simulation results of the vertical displacement, acceleration and dynamic deflection of the vehicle body show that the vibration isolation capability of the active mount system is superior to that of the passive mount system. It shows that compared with the passive mount, LQR active mount can greatly improve the vibration isolation performance, which proves the feasibility and effectiveness of the LQR control method.

Mounting clips for panel installation

Science.gov (United States)

Cavieres, Andres; Al-Haddad, Tristan; Goodman, Joseph; Valdes, Francisco

2017-02-14

An exemplary mounting clip for removably attaching panels to a supporting structure comprises a base, spring locking clips, a lateral flange, a lever flange, and a spring bonding pad. The spring locking clips extend upwardly from the base. The lateral flange extends upwardly from a first side of the base. The lateral flange comprises a slot having an opening configured to receive at least a portion of one of the one or more panels. The lever flange extends outwardly from the lateral flange. The spring bonding flange extends downwardly from the lever flange. At least a portion of the first spring bonding flange comprises a serrated edge for gouging at least a portion of the one or more panels when the one or more panels are attached to the mounting clip to electrically and mechanically couple the one or more panels to the mounting clip.

Photoelectric panel with equatorial mounting of drive

Science.gov (United States)

Kukhta, M. S.; Krauinsh, P. Y.; Krauinsh, D. P.; Sokolov, A. P.; Mainy, S. B.

2018-03-01

The relevance of the work is determined by the need to create effective models for sunny energy. The article considers a photoelectric panel equipped with a system for tracking the sun. Efficiency of the system is provided by equatorial mounting, which compensates for the rotation of the Earth by rotating the sunny panel in the plane of the celestial equator. The specificity of climatic and geographical conditions of Tomsk is estimated. The dynamics of power variations of photoelectric panels with equatorial mounting during seasonal fluctuations in Tomsk is calculated. A mobile photovoltaic panel with equatorial mounting of the drive has been developed. The methods of design strategy for placing photovoltaic panels in the architectural environment of the city are presented. Key words: sunny energy, photovoltaics, equatorial mounting, mechatronic model, wave reducer, electric drive.

A pilot training manual for the terminal configured vehicle electronic horizontal situation indicator

Science.gov (United States)

Houck, J. A.

1981-01-01

The initial phase of a training program for the Terminal Configured Vehicle Electronic Situation indicator (EHSI) is presented. The EHSI and its symbology is introduced and interpretation of the symbols is explained. Basic symbols shown on the display at all times are first presented. Additional optional symbols to be used as appropriate during different portions of a flight are then introduced and various display configurations interpreted. The upper half of each page is a reproduction of the EHSI display or other pertinent instructional material and the bottom half contains explanatory text, simplifying production of an audiovisual package for use with large training classes. Two quizzes on the course material are included.

[The controversy of routine articulator mounting in orthodontics].

Science.gov (United States)

Wang, Li; Han, Xianglong; Bai, Ding

2013-06-01

Articulators have been widely used by clinicians of dentistry. But routine articulator mounting is still controversial in orthodontics. Orthodontists oriented by gnathology approve routine articulator mounting while nongnathologic orthodontists disapprove it. This article reviews the thoughts of orthodontist that they agree or disagree with routine articulator mounting based on the considerations of biting, temporomandibular disorder (TMD), periodontitis, and so on.

Change Blindness Phenomena for Virtual Reality Display Systems.

Science.gov (United States)

Steinicke, Frank; Bruder, Gerd; Hinrichs, Klaus; Willemsen, Pete

2011-09-01

In visual perception, change blindness describes the phenomenon that persons viewing a visual scene may apparently fail to detect significant changes in that scene. These phenomena have been observed in both computer-generated imagery and real-world scenes. Several studies have demonstrated that change blindness effects occur primarily during visual disruptions such as blinks or saccadic eye movements. However, until now the influence of stereoscopic vision on change blindness has not been studied thoroughly in the context of visual perception research. In this paper, we introduce change blindness techniques for stereoscopic virtual reality (VR) systems, providing the ability to substantially modify a virtual scene in a manner that is difficult for observers to perceive. We evaluate techniques for semiimmersive VR systems, i.e., a passive and active stereoscopic projection system as well as an immersive VR system, i.e., a head-mounted display, and compare the results to those of monoscopic viewing conditions. For stereoscopic viewing conditions, we found that change blindness phenomena occur with the same magnitude as in monoscopic viewing conditions. Furthermore, we have evaluated the potential of the presented techniques for allowing abrupt, and yet significant, changes of a stereoscopically displayed virtual reality environment.

Development of a Double Glass Mounting Method Using Formaldehyde Alcohol Azocarmine Lactophenol (FAAL) and its Evaluation for Permanent Mounting of Small Nematodes.

Science.gov (United States)

Zahabiun, Farzaneh; Sadjjadi, Seyed Mahmoud; Esfandiari, Farideh

2015-01-01

Permanent slide preparation of nematodes especially small ones is time consuming, difficult and they become scarious margins. Regarding this problem, a modified double glass mounting method was developed and compared with classic method. A total of 209 nematode samples from human and animal origin were fixed and stained with Formaldehyde Alcohol Azocarmine Lactophenol (FAAL) followed by double glass mounting and classic dehydration method using Canada balsam as their mounting media. The slides were evaluated in different dates and times, more than four years. Different photos were made with different magnification during the evaluation time. The double glass mounting method was stable during this time and comparable with classic method. There were no changes in morphologic structures of nematodes using double glass mounting method with well-defined and clear differentiation between different organs of nematodes in this method. Using this method is cost effective and fast for mounting of small nematodes comparing to classic method.

OLED Display For Real Time Vision System

Directory of Open Access Journals (Sweden)

Sandhyalakshmi Narayanan

2015-08-01

Full Text Available This innovative glass design will carry an OLED based display controlled via nano Ardiuno board having Bluetooth connectivity with a Smartphone to exchange information along with onboard accelerometer. We are using a tilt angle sensor for detecting if the driver is feeling drowsy. An alcohol sensor has been used to promote the safe driving habit. The glasses will be getting latest updates about the current speed of the vehicle navigation directions nearby or approaching sign broads or services like petrol pumps. Itll also display information like incoming calls or received messages. All this information will be obtained through a Smartphone connected via Bluetooth. Also the car mileage can be monitored with help of fuel sensor as the consumption of fuel is directly related to it. Abnormalities if detected will be immediately notified in the glasses. Also the angle of the tilt angle sensor can be defined and set by the user according to his needs. Also the main idea of using OLED glasses is that it is organic thereby helps in reducing the carbon footprint and is quite slim. Therefore it can be easily mounted on the specs without making it heavy. Also they higher level of flexibility and have low power drain and energy consumption

The Identification of War-Fighting Symbology With the Use of a Small Display

Science.gov (United States)

2006-05-01

decreases in performance. Eight active-duty Soldiers determined if target symbols were present on or absent from map images containing distractor symbols...5 Figure 2. Examples of the no-map and map environments (not drawn to scale).............................8 Figure 3. Images presented in...a no-map or map background. Symbol size (i.e., stimulus intensity) was measured in “points”. “In typography , a point is about 1/72 of an inch

Improved resolution by mounting of tissue sections for laser microdissection.

Science.gov (United States)

van Dijk, M C R F; Rombout, P D M; Dijkman, H B P M; Ruiter, D J; Bernsen, M R

2003-08-01

Laser microbeam microdissection has greatly facilitated the procurement of specific cell populations from tissue sections. However, the fact that a coverslip is not used means that the morphology of the tissue sections is often poor. To develop a mounting method that greatly improves the morphological quality of tissue sections for laser microbeam microdissection purposes so that the identification of target cells can be facilitated. Fresh frozen tissue and formalin fixed, paraffin wax embedded tissue specimens were used to test the morphological quality of mounted and unmounted tissue. The mounting solution consisted of an adhesive gum and blue ink diluted in water. Interference of the mounting solution with DNA quality was analysed by the polymerase chain reaction using 10-2000 cells isolated by microdissection from mounted and unmounted tissue. The mounting solution greatly improved the morphology of tissue sections for laser microdissection purposes and had no detrimental effects on the isolation and efficiency of amplification of DNA. One disadvantage was that the mounting solution reduced the cutting efficiency of the ultraviolet laser. To minimise this effect, the mounting solution should be diluted as much as possible. Furthermore, the addition of blue ink to the mounting medium restores the cutting efficiency of the laser. The mounting solution is easy to prepare and apply and can be combined with various staining methods without compromising the quality of the DNA extracted.

Horse-related injuries in children - unmounted injuries are more severe: A retrospective review.

Science.gov (United States)

Wolyncewicz, Grace E L; Palmer, Cameron S; Jowett, Helen E; Hutson, John M; King, Sebastian K; Teague, Warwick J

2018-05-01

Horse-related injuries account for one quarter of all paediatric sports fatalities. It is not known whether the pattern of injury spectrum and severity differ between children injured whilst mounted, compared with those injured unmounted around horses. We aimed to identify any distinctions between the demographic features, spectrum and severity of injuries for mounted versus unmounted patients. Trauma registry data were reviewed for 505 consecutive paediatric patients (agedinjuries over a 16-year period. Patients were classified into mounted and unmounted groups, and demographics, injury spectrum, injury severity, and helmet usage compared using odds ratios and Wilcoxon rank-sum tests. More patients (56%) were injured in a private setting than in a sporting or supervised context (23%). Overall, head injuries were the most common horse-related injury. Mounted patients comprised 77% of the cohort. Mounted patients were more likely to sustain upper limb fractures or spinal injuries, and more likely to wear helmets. Unmounted were more likely to be younger males, and more likely to sustain facial or abdominal injuries. Strikingly, unmounted children had significantly more severe and critical Injury Severity Scores (OR 2.6; 95% CI 1.5, 4.6) and longer hospital stay (2.0days vs 1.1days; pinjury. Horse-related injuries in children are serious. Unmounted patients are distinct from mounted patients in terms of gender, age, likelihood of personal protective equipment use, severity of injuries, and requirement for intensive or invasive care. This study highlights the importance of vigilance and other safety behaviours when unmounted and around horses, and proposes specific targets for future injury prevention campaigns, both in setting of organised and private equestrian activity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Isolation Mounting for Charge-Coupled Devices

Science.gov (United States)

Goss, W. C.; Salomon, P. M.

1985-01-01

CCD's suspended by wires under tension. Remote thermoelectric cooling of charge coupled device allows vibration isolating mounting of CCD assembly alone, without having to suspend entire mass and bulk of thermoelectric module. Mounting hardware simple and light. Developed for charge-coupled devices (CCD's) in infrared telescope support adaptable to sensors in variety of environments, e.g., sensors in nuclear reactors, engine exhausts and plasma chambers.

Flow distortion on boom mounted cup anemometers

DEFF Research Database (Denmark)

Lindelöw, Per Jonas Petter; Friis Pedersen, Troels; Gottschall, Julia

In this report we investigate on wind direction dependent errors in the measurement of the horizontal wind speed by boom mounted cup anemometers. The boom mounting on the studied lattice tower is performed according to IEC standard design rules, yet, larger deviations than predicted by flow models...... are observed. The errors on the measurements are likely caused by an underestimation of the flow distortions around the tower. In this paper an experimental method for deriving a correction formula and an in-field calibration is suggested. The method is based on measurements with two cup anemometers mounted...

The neurosurgeon as baseball fan and inventor: Walter Dandy and the batter's helmet.

Science.gov (United States)

Brewster, Ryan; Bi, Wenya Linda; Smith, Timothy R; Gormley, William B; Dunn, Ian F; Laws, Edward R

2015-07-01

Baseball maintains one of the highest impact injury rates in all athletics. A principal causative factor is the "beanball," referring to a pitch thrown directly at a batter's head. Frequent morbidities elicited demand for the development of protective gear development in the 20th century. In this setting, Dr. Walter Dandy was commissioned to design a "protective cap" in 1941. His invention became widely adopted by professional baseball and inspired subsequent generations of batting helmets. As a baseball aficionado since his youth, Walter Dandy identified a natural partnership between baseball and medical practice for the reduction of beaning-related brain injuries. This history further supports the unique position of neurosurgeons to leverage clinical insights, inform innovation, and expand service to society.

Use of display technologies for augmented reality enhancement

Science.gov (United States)

Harding, Kevin

2016-06-01

Augmented reality (AR) is seen as an important tool for the future of user interfaces as well as training applications. An important application area for AR is expected to be in the digitization of training and worker instructions used in the Brilliant Factory environment. The transition of work instructions methods from printed pages in a book or taped to a machine to virtual simulations is a long step with many challenges along the way. A variety of augmented reality tools are being explored today for industrial applications that range from simple programmable projections in the work space to 3D displays and head mounted gear. This paper will review where some of these tool are today and some of the pros and cons being considered for the future worker environment.

Effects of Different Types of Virtual Reality Display on Presence and Learning in a Safety Training Scenario.

Science.gov (United States)

Buttussi, Fabio; Chittaro, Luca

2018-02-01

The increasing availability of head-mounted displays (HMDs) for home use motivates the study of the possible effects that adopting this new hardware might have on users. Moreover, while the impact of display type has been studied for different kinds of tasks, it has been scarcely explored in procedural training. Our study considered three different types of displays used by participants for training in aviation safety procedures with a serious game. The three displays were respectively representative of: (i) desktop VR (a standard desktop monitor), (ii) many setups for immersive VR used in the literature (an HMD with narrow field of view and a 3-DOF tracker), and (iii) new setups for immersive home VR (an HMD with wide field of view and 6-DOF tracker). We assessed effects on knowledge gain, and different self-reported measures (self-efficacy, engagement, presence). Unlike previous studies of display type that measured effects only immediately after the VR experience, we considered also a longer time span (2 weeks). Results indicated that the display type played a significant role in engagement and presence. The training benefits (increased knowledge and self-efficacy) were instead obtained, and maintained at two weeks, regardless of the display used. The paper discusses the implications of these results.

Transducer-Mounting Fixture

Science.gov (United States)

Spiegel, Kirk W.

1990-01-01

Transducer-mounting fixture holds transducer securely against stud. Projects only slightly beyond stud after installation. Flanged transducer fits into fixture when hinged halves open. When halves reclosed, fixture tightened onto threaded stud until stud makes contact with transducer. Knurled area on fixture aids in tightening fixture on stud.

49 CFR 571.212 - Standard No. 212; Windshield mounting.

Science.gov (United States)

2010-10-01

... 49 Transportation 6 2010-10-01 2010-10-01 false Standard No. 212; Windshield mounting. 571.212... Motor Vehicle Safety Standards § 571.212 Standard No. 212; Windshield mounting. S1. Scope. This standard..., under the conditions of S6, the windshield mounting of the vehicle shall retain not less than the...

A Dosimetric Evaluation of Conventional Helmet Field Irradiation Versus Two-Field Intensity-Modulated Radiotherapy Technique

International Nuclear Information System (INIS)

Yu, James B.; Shiao, Stephen L.; Knisely, Jonathan

2007-01-01

Purpose: To compare dosimetric differences between conventional two-beam helmet field irradiation (external beam radiotherapy, EBRT) of the brain and a two-field intensity-modulated radiotherapy (IMRT) technique. Methods and Materials: Ten patients who received helmet field irradiation at our institution were selected for study. External beam radiotherapy portals were planned per usual practice. Intensity-modulated radiotherapy fields were created using the identical field angles as the EBRT portals. Each brain was fully contoured along with the spinal cord to the bottom of the C2 vertebral body. This volume was then expanded symmetrically by 0.5 cm to construct the planning target volume. An IMRT plan was constructed using uniform optimization constraints. For both techniques, the nominal prescribed dose was 3,000 cGy in 10 fractions of 300 cGy using 6-MV photons. Comparative dose-volume histograms were generated for each patient and analyzed. Results: Intensity-modulated radiotherapy improved dose uniformity over EBRT for whole brain radiotherapy. The mean percentage of brain receiving >105% of dose was reduced from 29.3% with EBRT to 0.03% with IMRT. The mean maximum dose was reduced from 3,378 cGy (113%) for EBRT to 3,162 cGy (105%) with IMRT. The mean percent volume receiving at least 98% of the prescribed dose was 99.5% for the conventional technique and 100% for IMRT. Conclusions: Intensity-modulated radiotherapy reduces dose inhomogeneity, particularly for the midline frontal lobe structures where hot spots occur with conventional two-field EBRT. More study needs to be done addressing the clinical implications of optimizing dose uniformity and its effect on long-term cognitive function in selected long-lived patients

New active machine tool drive mounting on the frame

Directory of Open Access Journals (Sweden)

Švéda J.

2007-10-01

Full Text Available The paper deals with the new active mounting of the machine tool drives. The commonly used machine tools are at this time mainly equipped with fix-mounting of the feed drives. This structure causes full transmission of the force shocks to the machine bed and thereby restricts the dynamic properties of the motion axis and the whole machine. The spring-mounting of the feed drives is one of the possibilities how to partially suppress the vibrations. The force that reacts to the machine tool bed is transformed thereby the vibrations are lightly reduced. Unfortunately the transformation is not fully controlled. The new active mounting of the machine tool drives allows to fully control the force behaviour that react to the machine body. Thereby the number of excited frequencies on the machine tool bed is significantly reduced. The active variant of the feed drive mounting is characterized by the synergistic cooperation between two series-connected actuators (“motor on motor”. The paper briefly describes design, control techniques and optimization of the feed drives with the new active mounting conception.

Organization and processes of the BN-600 reactor mounting

International Nuclear Information System (INIS)

Dubrovin, E.Z.; Karpenko, V.N.; Takhtaulov, V.M.

1982-01-01

Structural peculiarities of the BN-600 reactor plant are considered. Experience of metal structure mounting inside the reactor vessel has been analysed. Recommendations on the improvements on the organization of the thermal mechanical equipment mounting are given. It is concluded that the consideration of these recommendations will permit to reduce expenditures of labour by 10-40% for the mounting

46 CFR 61.05-15 - Boiler mountings and attachments.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Boiler mountings and attachments. 61.05-15 Section 61.05... TESTS AND INSPECTIONS Tests and Inspections of Boilers § 61.05-15 Boiler mountings and attachments. (a....05-10. (b) Each stud or bolt for each boiler mounting that paragraph (c) of this section requires to...

Linear and/or curvilinear rail mount system

Science.gov (United States)

Thomas, Jackie D. (Inventor); Harris, Lawanna L. (Inventor)

2012-01-01

One or more linear and/or curvilinear mounting rails are coupled to a structure. Each mounting rail defines a channel and at least one cartridge assembly is engaged in the channel. Each cartridge assembly includes a housing that slides within the channel. The housing defines a curvilinearly-shaped recess longitudinally aligned with the channel when the housing is in engagement therewith. The cartridge assembly also includes a cleat fitted in the recess for sliding engagement therealong. The cleat can be coupled to a fastener that passes through the mounting rail and the housing when the housing is so-engaged in the channel. The cleat is positioned in the recess by a position of the fastener.

Magma at depth: A retrospective analysis of the 1975 unrest at Mount Baker, Washington, USA

Science.gov (United States)

Crider, Juliet G.; Frank, David; Malone, Stephen D.; Poland, Michael P.; Werner, Cynthia; Caplan-Auerbach, Jacqueline

2011-01-01

Mount Baker volcano displayed a short interval of seismically-quiescent thermal unrest in 1975, with high emissions of magmatic gas that slowly waned during the following three decades. The area of snow-free ground in the active crater has not returned to pre-unrest levels, and fumarole gas geochemistry shows a decreasing magmatic signature over that same interval. A relative microgravity survey revealed a substantial gravity increase in the ~30 years since the unrest, while deformation measurements suggest slight deflation of the edifice between 1981-83 and 2006-07. The volcano remains seismically quiet with regard to impulsive volcano-tectonic events, but experiences shallow (10 km) long-period earthquakes. Reviewing the observations from the 1975 unrest in combination with geophysical and geochemical data collected in the decades that followed, we infer that elevated gas and thermal emissions at Mount Baker in 1975 resulted from magmatic activity beneath the volcano: either the emplacement of magma at mid-crustal levels, or opening of a conduit to a deep existing source of magmatic volatiles. Decadal-timescale, multi-parameter observations were essential to this assessment of magmatic activity.

Comparing the effectiveness of different displays in enhancing illusions of self-movement (vection

Directory of Open Access Journals (Sweden)

Bernhard E. Riecke

2015-06-01

Full Text Available Illusions of self-movement (vection can be used in Virtual Reality (VR and other applications to give users the embodied sensation that they are moving when physical movement is unfeasible or too costly. Whereas a large body of vection literature studied how various parameters of the presented visual stimulus affect vection, little is known how different display types might affect vection. As a step towards addressing this gap, we conducted three experiments to compare vection and usability parameters between commonly used VR displays, ranging from stereoscopic projection and 3D TV to high-end head-mounted display (HMD, NVIS SX111 and recent low-cost HMD (Oculus Rift. The last experiment also compared these two HMDs in their native full field of view FOV and a reduced, matched FOV of 72×45°. Participants moved along linear and curvilinear paths in the virtual environment, reported vection onset time, and rated vection intensity at the end of each trial. In addition, user ratings on immersion, motion sickness, vection, and overall preference were recorded retrospectively and compared between displays. Unexpectedly, there were no significant effects of display on vection measures. Reducing the FOV for the HMDs (from full to 72×45° decreased vection onset latencies, but did not affect vection intensity. As predicted, curvilinear paths yielded earlier and more intense vection. Although vection has often been proposed to predict or even cause motion sickness, we observed no correlation for any of the displays studied. In conclusion, perceived self-motion and other user experience measures proved surprisingly tolerant towards changes in display type as long as the FOV was roughly matched. This suggests that display choice for vection research and VR applications can be largely based on other considerations as long as the provided FOV is sufficiently large.

Methods and apparatus for radially compliant component mounting

Science.gov (United States)

Bulman, David Edward [Cincinnati, OH; Darkins, Jr., Toby George; Stumpf, James Anthony [Columbus, IN; Schroder, Mark S [Greenville, SC; Lipinski, John Joseph [Simpsonville, SC

2012-03-27

Methods and apparatus for a mounting assembly for a liner of a gas turbine engine combustor are provided. The combustor includes a combustor liner and a radially outer annular flow sleeve. The mounting assembly includes an inner ring surrounding a radially outer surface of the liner and including a plurality of axially extending fingers. The mounting assembly also includes a radially outer ring coupled to the inner ring through a plurality of spacers that extend radially from a radially outer surface of the inner ring to the outer ring.

Evaluation of Head Mounted and Head Down Information Displays During Simulated Mine-Countermeasures Dives to 42 msw

Science.gov (United States)

2008-04-01

visualisation tête basse (VTB) ou d’un visiocasque pour l’exécution de leurs tâches courantes sous l’eau. Neuf plongeurs de lutte contre les mines ont...existe peu d’information empirique sur l’aptitude des plongeurs à utiliser un dispositif multifonction de visualisation tête basse (VTB) ou d’un...experiment, the diver was also linked to the researchers and operations crew via audio communications. 11 Display Screen Chamber Laptop Diver

Vertical repositioning accuracy of magnetic mounting systems on 4 articulator models.

Science.gov (United States)

Lee, Wonsup; Kwon, Ho-Beom

2018-03-01

Research of the ability of a cast mounted on an articulator on maintaining the identical position of a cast mounted on an articulator after repeated repositioning is lacking, despite the possible effects this may have on the occlusion of a mounted cast. The purpose of this in vitro study was to verify and compare the vertical repositioning accuracy of 4 different, commercially available articulator magnetic mounting plate systems. Four articulators and their associated magnetic mounting plates were selected for the study. These were the Artex AR articulator (Amann Girrbach AG), the Denar Mark II articulator (Whip Mix Corp), the Kavo Protar Evo articulator (Kavo Dental GmbH), and the SAM3 articulator (SAM Präzisionstechnik GmbH). Three new magnetic mounting plates were prepared for each articulator system. The repositioning accuracy of each mounting plate was evaluated by comparing the standard deviation of the vertical distances measured between the mounting plate and a laser displacement sensor. The lower arm of the articulator was secured, and the vertical distance was measured by positioning the laser displacement sensor positioned vertically above the mounting plate. Once the vertical distance was measured, the mounting plate was detached from the articulator and reattached manually to prepare for the next measurement. This procedure was repeated 30 times for each of the 3 magnetic mounting plates. Data were analyzed by ANOVA for 2-stage nested design and the Levene test (α=.05). Significant differences were detected among articulator systems and between magnetic mounting plates of the same type. The standard deviations of the measurements made with the Artex AR articulator, Denar Mark II articulator, Kavo Protar Evo articulator, and SAM3 articulator were 0.0027, 0.0308, 0.0214, and 0.0215 mm, respectively. Thus, the repositioning accuracy could be ranked in the order as follows: Artex AR, Kavo Protar Evo, SAM3, and Denar Mark II. The position of the

Internally Mounting Strain Gages

Science.gov (United States)

Jett, J. R., Jr.

1984-01-01

Technique for mounting strain gages inside bolt or cylinder simultaneously inserts gage, attached dowel segment, and length of expandable tubing. Expandable tubing holds gage in place while adhesive cures, assuring even distribution of pressure on gage and area gaged.

Application of Evolutionary Computation in Automotive Powertrain Mount Tuning

Directory of Open Access Journals (Sweden)

Anab Akanda

2006-01-01

Full Text Available Engine mount tuning is a multi-disciplinary exercise since it affects Idle-shake, Road-shake and power-train noise response. Engine inertia is often used as a tuned absorber for controlling suspension resonance related road-shake issues. Last but not least, vehicle ride and handling may also be affected by mount tuning. In this work, Torque-Roll-Axis (TRA decoupling of the rigid powertrain was used as a starting point for mount tuning. Nodal point of flexible powertrain bending was used to define the envelop for transmission mount locations. The frequency corresponding to the decoupled roll mode of the rigid powertrain was then adjusted for idle-shake and road-shake response management.

Flat mount preparation for observation and analysis of zebrafish embryo specimens stained by whole mount in situ hybridization.

Science.gov (United States)

Cheng, Christina N; Li, Yue; Marra, Amanda N; Verdun, Valerie; Wingert, Rebecca A

2014-07-17

The zebrafish embryo is now commonly used for basic and biomedical research to investigate the genetic control of developmental processes and to model congenital abnormalities. During the first day of life, the zebrafish embryo progresses through many developmental stages including fertilization, cleavage, gastrulation, segmentation, and the organogenesis of structures such as the kidney, heart, and central nervous system. The anatomy of a young zebrafish embryo presents several challenges for the visualization and analysis of the tissues involved in many of these events because the embryo develops in association with a round yolk mass. Thus, for accurate analysis and imaging of experimental phenotypes in fixed embryonic specimens between the tailbud and 20 somite stage (10 and 19 hours post fertilization (hpf), respectively), such as those stained using whole mount in situ hybridization (WISH), it is often desirable to remove the embryo from the yolk ball and to position it flat on a glass slide. However, performing a flat mount procedure can be tedious. Therefore, successful and efficient flat mount preparation is greatly facilitated through the visual demonstration of the dissection technique, and also helped by using reagents that assist in optimal tissue handling. Here, we provide our WISH protocol for one or two-color detection of gene expression in the zebrafish embryo, and demonstrate how the flat mounting procedure can be performed on this example of a stained fixed specimen. This flat mounting protocol is broadly applicable to the study of many embryonic structures that emerge during early zebrafish development, and can be implemented in conjunction with other staining methods performed on fixed embryo samples.

UHV mirror mounts for photophysics beamline at Indus-I

International Nuclear Information System (INIS)

Meenakshi Raja Rao, P.; Bhattacharya, S.S.; Das, N.C.; Rajasekhar, B.N.; Roy, A.P.

1995-01-01

Photophysics beamline makes use of a combination of two toroidal mirrors and one meter Seya-Namioka Monochromator in its fore optics. The fore optics monochromatises and steers the synchrotron radiation source (SRS) beam from its tangent point to the sample situated at a distance of about five meters. Slit widths of the monochromator are of the order of 100μ and the sample size is one mm 2 . Hence it is essential to impart precision rotational and translational movements of the same order of magnitude to the mirrors with the use of appropriate mirror mounts. Since Indus-1 operates at a pressure -9 mbar, the mirror mounts should be UHV compatible and the movements should be actuated under UHV. The mirrors along with the mirror mounts are enclosed in UHV chambers. The mirror chambers have been fabricated at Centre for Advanced Technology (CAT) workshops and tested up to a pressure of 10 -9 mbar. The mirror mounts are designed, fabricated and leak checked (He leak rate -10 std cc/s) The precision movements are achieved with the help of bellow sealed shaft mechanism and adjustable screws provided with the kinematic mount of the mirror frame. The performance of the mirror mount was tested at atmospheric pressure by using a laser beam and found to be good. The minimum displacement of the laser beam at slit and sample positions is ∼ 70μ which is quite adequate for optical alignment. The performance of the mirror mount under UHV conditions is being evaluated. (author). 4 refs., 3 figs

Hall Current Plasma Source Having a Center-Mounted or a Surface-Mounted Cathode

Science.gov (United States)

Martinez, Rafael A. (Inventor); Williams, John D. (Inventor); Moritz, Jr., Joel A. (Inventor); Farnell, Casey C. (Inventor)

2018-01-01

A miniature Hall current plasma source apparatus having magnetic shielding of the walls from ionized plasma, an integrated discharge channel and gas distributor, an instant-start hollow cathode mounted to the plasma source, and an externally mounted keeper, is described. The apparatus offers advantages over other Hall current plasma sources having similar power levels, including: lower mass, longer lifetime, lower part count including fewer power supplies, and the ability to be continuously adjustable to lower average power levels using pulsed operation and adjustment of the pulse duty cycle. The Hall current plasma source can provide propulsion for small spacecraft that either do not have sufficient power to accommodate a propulsion system or do not have available volume to incorporate the larger propulsion systems currently available. The present low-power Hall current plasma source can be used to provide energetic ions to assist the deposition of thin films in plasma processing applications.

Galvanic coupling effects for module-mounting elements of ground-mounted photovoltaic power station

Directory of Open Access Journals (Sweden)

Pierozynski Boguslaw

2017-12-01

Full Text Available This communication reports on the concerns associated with possible generation of galvanic coupling effects for construction materials that are used to manufacture mounting assemblies for ground-mounted photovoltaic (PV power stations. For this purpose, six macro-corrosion galvanic cells were assembled, including: hot-dip Zn/Magnelis®-coated steel/Al and stainless steel (SS/Al cells. Corrosion experiments involved continuous, ca. three-month exposure of these couplings in 3 wt.% NaCl solution, conducted at room temperature for a stable pH value of around 8. All corrosion cells were subjected to regular assessment of galvanic current-density and potential parameters, where special consideration was given to compare the corrosion behaviour of Zn-coated steel samples with that of Magnelis®-coated electrodes. Characterization of surface condition and elemental composition for examined materials was carried-out by means of SEM and EDX spectroscopy techniques.

COMBINING INDEPENDENT VISUALIZATION AND TRACKING SYSTEMS FOR AUGMENTED REALITY

Directory of Open Access Journals (Sweden)

P. Hübner

2018-05-01

Full Text Available The basic requirement for the successful deployment of a mobile augmented reality application is a reliable tracking system with high accuracy. Recently, a helmet-based inside-out tracking system which meets this demand has been proposed for self-localization in buildings. To realize an augmented reality application based on this tracking system, a display has to be added for visualization purposes. Therefore, the relative pose of this visualization platform with respect to the helmet has to be tracked. In the case of hand-held visualization platforms like smartphones or tablets, this can be achieved by means of image-based tracking methods like marker-based or model-based tracking. In this paper, we present two marker-based methods for tracking the relative pose between the helmet-based tracking system and a tablet-based visualization system. Both methods were implemented and comparatively evaluated in terms of tracking accuracy. Our results show that mobile inside-out tracking systems without integrated displays can easily be supplemented with a hand-held tablet as visualization device for augmented reality purposes.

Fusion Helmet: Electronic Analysis

Science.gov (United States)

2014-04-01

Table 1: LYR203-101B Board Feature P1 (SEC MODULE) DM648 GPIO PORn Video Ports (2) Bootmode SPI/UART I2C CLKIN MDIO DDR2 128MB/16bit SPI Flash 16...McASP EMAC-SGMII /2 MDIO I2C GPIO DDR2 128MB/16bit JTAG Memory CLKGEN I2C PGoodPGood PORn Pwr LED Power DSP SPI/UART DSP SPI/UARTSPI/UART Video Display

The alpine flora of Mount Wilhelm (New Guinea)

NARCIS (Netherlands)

Hoogland, R.D.

1958-01-01

The flora of the higher mountains of New Guinea has been the object of several extensive collecting trips in the past forty years. Until quite recently, however, a serious gap in our knowledge was the very scanty information available from the area between Mount Wilhelmina in the West and Mount

Optimization of Classical Hydraulic Engine Mounts Based on RMS Method

Directory of Open Access Journals (Sweden)

J. Christopherson

2005-01-01

Full Text Available Based on RMS averaging of the frequency response functions of the absolute acceleration and relative displacement transmissibility, optimal parameters describing the hydraulic engine mount are determined to explain the internal mount geometry. More specifically, it is shown that a line of minima exists to define a relationship between the absolute acceleration and relative displacement transmissibility of a sprung mass using a hydraulic mount as a means of suspension. This line of minima is used to determine several optimal systems developed on the basis of different clearance requirements, hence different relative displacement requirements, and compare them by means of their respective acceleration and displacement transmissibility functions. In addition, the transient response of the mount to a step input is also investigated to show the effects of the optimization upon the time domain response of the hydraulic mount.

Mirror boxes and mirror mounts for photophysics beamline

International Nuclear Information System (INIS)

Raja Rao, P.M.; Raja Sekhar, B.N.; Das, N.C.; Khan, H.A.; Bhattacharya, S.S.; Roy, A.P.

1996-01-01

Photophysics beamline makes use of one metre Seya-Namioka monochromator and two toroidal mirrors in its fore optics. The first toroidal mirror (pre mirror) focuses light originating from the tangent point of the storage ring onto the entrance slit of the monochromator and second toroidal mirror (post mirror) collects light from the exit slit of the monochromator and focuses light onto the sample placed at a distance of about one metre away from the 2nd mirror. To steer light through monochromator and to focus it on the sample of 1mm x 1mm size require precision rotational and translational motion of the mirrors and this has been achieved with the help of precision mirror mounts. Since Indus-1 operates at pressures less than 10 -9 m.bar, the mirror mounts should be manipulated under similar ultra high vacuum conditions. Considering these requirements, two mirror boxes and two mirror mounts have been designed and fabricated. The coarse movements to the mirrors are imparted from outside the mirror chamber with the help of x-y tables and precision movements to the mirrors are achieved with the help of mirror mounts. The UHV compatibility and performance of the mirror mounts connected to mirror boxes under ultra high vacuum condition is evaluated. The details of the design, fabrication and performance evaluation are discussed in this report. 5 refs., 9 figs., 1 tab

Head-worn display-based augmented reality system for manufacturing

Science.gov (United States)

Sarwal, Alok; Baker, Chris; Filipovic, Dragan

2005-05-01

This system provides real-time guidance for training and problem-solving on production-line machinery. A prototype of a wearable, real-time, video guidance, interactive system for use in manufacturing, has been developed and demonstrated. Anticipated benefits are: relatively inexperienced personnel can provide machine servicing and the dependency on the vendor to repair or maintain equipment is significantly reduced. Additionally, servicing, training or part change-over schedules can be exercised more predictably and with less training. This approach utilizes Head Worn Display or Head Mounted Display (HMD) technology that can be readily adapted for various machines on the factory floor with training steps for a new location. Such a system can support various applications in manufacturing such as direct video guiding or applying scheduled maintenance and training to effectively resolve servicing emergencies and reduce machine downtime. It can also provide training of inexperienced operators and maintenance personnel. The gap between production line complexity and ability of production personnel to effectively maintain equipment is expected to widen in the future and advanced equipment will require complex servicing procedures that are neither well documented nor user-friendly. This system offers benefits in increased manufacturing equipment availability by facilitating effective servicing and training and can interface to a server system for additional computational resources on an as-needed basis. This system utilizes markers to guide the user and enforces a well defined sequence of operations. It performs augmentation of information on the display in order to provide guidance in real-time.

Ball mounting fixture for a roundness gage

Science.gov (United States)

Gauler, Allen L.; Pasieka, Donald F.

1983-01-01

A ball mounting fixture for a roundness gage is disclosed. The fixture includes a pair of chuck assemblies oriented substantially transversely with respect to one another and mounted on a common base. Each chuck assembly preferably includes a rotary stage and a wobble plate affixed thereto. A ball chuck affixed to each wobble plate is operable to selectively support a ball to be measured for roundness, with the wobble plate permitting the ball chuck to be tilted to center the ball on the axis of rotation of the rotary stage. In a preferred embodiment, each chuck assembly includes a vacuum chuck operable to selectively support the ball to be measured for roundness. The mounting fixture enables a series of roundness measurements to be taken with a conventional rotating gagehead roundness instrument, which measurements can be utilized to determine the sphericity of the ball.

Tension pneumocephalus: Mount Fuji sign

Directory of Open Access Journals (Sweden)

Pulastya Sanyal

2015-01-01

Full Text Available A 13-year-old male was operated for a space occupying lesion in the brain. A noncontrast computed tomography scan done in the late postoperative period showed massive subdural air collection causing compression of bilateral frontal lobes with widening of interhemispheric fissure and the frontal lobes acquiring a peak like configuration - causing tension pneumocephalus-"Mount Fuji sign." Tension pneumocephalus occurs when air enters the extradural or intradural spaces in sufficient volume to exert a mass or pressure effect on the brain, leading to brain herniation. Tension pneumocephalus is a surgical emergency, which needs immediate intervention in the form of decompression of the cranial cavity by a burr hole or needle aspiration. The Mount Fuji sign differentiates tension pneumocephalus from pneumocephalus.

Enhanced/Synthetic Vision Systems - Human factors research and implications for future systems

Science.gov (United States)

Foyle, David C.; Ahumada, Albert J.; Larimer, James; Sweet, Barbara T.