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Maria Majar - One of the best experts on this subject based on the ideXlab platform.
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Sound Level Measurements in Berthing Areas of an Aircraft Carrier.
Annals of work exposures and health, 2019Co-Authors: Nicholas Schaal, Maria Majar, Andrew J. HunterAbstract:BACKGROUND Personnel assigned to Aircraft Carriers work and live in environments where hazardous noise areas and hearing recovery spaces such as sleeping areas are in close proximity to one another. Hazardous noise exposure occurring during on-duty time periods and elevated noise levels during off-duty periods in sleeping areas may be prohibiting adequate hearing recovery, thus potentially leading to hearing loss and may lead to adverse effects on sleep, leading to crew-member fatigue. This investigation characterizes Equivalent sound level (Leq) and standardized octave band center frequency noise levels according to berthing (sleeping) area location during flight operation and nonflight operation time periods on a US Navy Aircraft Carrier. In addition, the investigation compares noise measurements in sleeping areas to noise levels associated with auditory rest and poor sleep quality and quantity. METHODS Noise levels were measured in berthing areas aboard a US Navy Nimitz-class Aircraft Carrier during a routine at-sea period. Sixty noise measurements were taken in eight sleeping locations. Leq in decibels 'A' weighted (dBA) and noise levels from 16 to 16 000 Hz in (dB) were measured during flight operations [Leq (flt ops)] and nonflight operations [Leq (nonflt ops)]. Leq was also measured according to sleep area shipboard locations of forward (FWD) Leq (FWD), middle (MID) Leq (MID), and rear (AFT) Leq (AFT). These data were compared to the 70 dBA American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit value (TLV) for effective quiet areas. In addition, these data were compared to noise levels associated with hearing loss and sleep parameters. Statistical analysis was conducted with R version 3.5.2 using an alpha level of 0.05. RESULTS Leq (flt ops) in sleeping areas was a statistically significant (P < 0.05) 6.4 dBA higher than the Leq (nonflt ops). Leq (FWD) and Leq (MID) in sleeping areas was a statistically significant (P < 0.05) 15.2 and 15.0 dBA higher, respectively, than the Leq (AFT) noise levels. Mean noise levels at standardized center (1/1) octave bands were highest between 500 and 4000 Hz, ranging from 65.2 to 69.8 dB. A total of 72% of all area Leq measurements exceeded the 70 dBA ACGIH TLV classified as effective quiet to allow for temporary threshold shift recovery. All noise measurements exceeded the World Health Organization's noise threshold where adverse effects on sleep begin. DISCUSSION/CONCLUSIONS Results suggest that sleeping area location in close proximity to relatively high noise sources and activities occurring on an Aircraft Carrier (i.e. flight operations) increase noise levels in sleeping areas. These findings raise serious concerns since high noise exposures both on duty and during off-duty/sleeping periods may inhibit auditory recovery from hazardous noise exposures. In addition, results suggest noise levels in sleeping areas are high enough to evoke negative sleep effects.
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Noise at sea: Characterization of extended shift noise exposures among U.S. Navy Aircraft Carrier support personnel.
Journal of occupational and environmental hygiene, 2019Co-Authors: Nicholas Schaal, Kevin Lange, Maria MajarAbstract:The purpose of this investigation was to characterize 12-hr on-duty, 12-hr off-duty, and 24-hr noise exposures among U.S. Navy Aircraft Carrier support personnel. Noise dosimetry samples were colle...
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Noise at sea: Characterization of extended shift noise exposures among U.S. Navy Aircraft Carrier support personnel
2019Co-Authors: Nicholas Schaal, Kevin Lange, Maria MajarAbstract:The purpose of this investigation was to characterize 12-hr on-duty, 12-hr off-duty, and 24-hr noise exposures among U.S. Navy Aircraft Carrier support personnel. Noise dosimetry samples were collected for 47 Aircraft Carrier support personnel while at sea during airwing Carrier qualifications. Leq measurements during 12-hr on-duty, 12-hr off-duty, and over 24-hr periods were compared to Threshold Limit Values. Four similar exposure groups (SEGs) were created based upon departmental assignment and similarity of work tasks: (1) Administration/Religious Ministries/Legal/Training, (2) Combat Systems/Operations, (3) Medical/Dental, and (4) Supply. Equivalent sound level (Leq) measurements in decibels “A” weighted (dBA) were compared to determine significant differences between each group according to 12-hr on-duty, 12-hr off-duty, and 24-hr periods. Mean 24-hr noise levels ranged from 69–88 dBA with 22% exceeding the 80 dBA Threshold Limit Value. Twelve-hr on-duty noise levels ranged from 71–90 dBA with 17% exceeding the 83 dBA 12-hr on-duty Threshold Limit Value. Twelve-hr off-duty noise exposure ranged from 68–84 dBA with 95% exceeding the 70 dBA American Conference of Governmental Industrial Hygienists threshold classified as effective quiet to allow for temporary threshold shift recovery. Welch Analysis of Variance and Dunnett T3 post hoc tests revealed SEG 2 had significantly higher 24-hr noise exposures than SEG 3 (p = 0.019) and SEG 4 (p = 0.045). SEG 2 had significantly higher 12-hr on-duty noise exposure than SEG 3 (p = 0.030). One Way Analysis of Variance revealed no significant differences between 12-hr off-duty noise exposures according to SEG (p = .096). Some Aircraft Carrier support personnel had 12-hr on-duty and 24-hr noise exposures exceeding Threshold Limit Values with a large proportion exceeding the 70 dBA effective quiet limit during 12-hr off-duty periods. Results suggest personnel that are typically considered low risk for hazardous noise exposure (
Nicholas Schaal - One of the best experts on this subject based on the ideXlab platform.
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Sound Level Measurements in Berthing Areas of an Aircraft Carrier.
Annals of work exposures and health, 2019Co-Authors: Nicholas Schaal, Maria Majar, Andrew J. HunterAbstract:BACKGROUND Personnel assigned to Aircraft Carriers work and live in environments where hazardous noise areas and hearing recovery spaces such as sleeping areas are in close proximity to one another. Hazardous noise exposure occurring during on-duty time periods and elevated noise levels during off-duty periods in sleeping areas may be prohibiting adequate hearing recovery, thus potentially leading to hearing loss and may lead to adverse effects on sleep, leading to crew-member fatigue. This investigation characterizes Equivalent sound level (Leq) and standardized octave band center frequency noise levels according to berthing (sleeping) area location during flight operation and nonflight operation time periods on a US Navy Aircraft Carrier. In addition, the investigation compares noise measurements in sleeping areas to noise levels associated with auditory rest and poor sleep quality and quantity. METHODS Noise levels were measured in berthing areas aboard a US Navy Nimitz-class Aircraft Carrier during a routine at-sea period. Sixty noise measurements were taken in eight sleeping locations. Leq in decibels 'A' weighted (dBA) and noise levels from 16 to 16 000 Hz in (dB) were measured during flight operations [Leq (flt ops)] and nonflight operations [Leq (nonflt ops)]. Leq was also measured according to sleep area shipboard locations of forward (FWD) Leq (FWD), middle (MID) Leq (MID), and rear (AFT) Leq (AFT). These data were compared to the 70 dBA American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit value (TLV) for effective quiet areas. In addition, these data were compared to noise levels associated with hearing loss and sleep parameters. Statistical analysis was conducted with R version 3.5.2 using an alpha level of 0.05. RESULTS Leq (flt ops) in sleeping areas was a statistically significant (P < 0.05) 6.4 dBA higher than the Leq (nonflt ops). Leq (FWD) and Leq (MID) in sleeping areas was a statistically significant (P < 0.05) 15.2 and 15.0 dBA higher, respectively, than the Leq (AFT) noise levels. Mean noise levels at standardized center (1/1) octave bands were highest between 500 and 4000 Hz, ranging from 65.2 to 69.8 dB. A total of 72% of all area Leq measurements exceeded the 70 dBA ACGIH TLV classified as effective quiet to allow for temporary threshold shift recovery. All noise measurements exceeded the World Health Organization's noise threshold where adverse effects on sleep begin. DISCUSSION/CONCLUSIONS Results suggest that sleeping area location in close proximity to relatively high noise sources and activities occurring on an Aircraft Carrier (i.e. flight operations) increase noise levels in sleeping areas. These findings raise serious concerns since high noise exposures both on duty and during off-duty/sleeping periods may inhibit auditory recovery from hazardous noise exposures. In addition, results suggest noise levels in sleeping areas are high enough to evoke negative sleep effects.
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Noise at sea: Characterization of extended shift noise exposures among U.S. Navy Aircraft Carrier support personnel.
Journal of occupational and environmental hygiene, 2019Co-Authors: Nicholas Schaal, Kevin Lange, Maria MajarAbstract:The purpose of this investigation was to characterize 12-hr on-duty, 12-hr off-duty, and 24-hr noise exposures among U.S. Navy Aircraft Carrier support personnel. Noise dosimetry samples were colle...
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Noise at sea: Characterization of extended shift noise exposures among U.S. Navy Aircraft Carrier support personnel
2019Co-Authors: Nicholas Schaal, Kevin Lange, Maria MajarAbstract:The purpose of this investigation was to characterize 12-hr on-duty, 12-hr off-duty, and 24-hr noise exposures among U.S. Navy Aircraft Carrier support personnel. Noise dosimetry samples were collected for 47 Aircraft Carrier support personnel while at sea during airwing Carrier qualifications. Leq measurements during 12-hr on-duty, 12-hr off-duty, and over 24-hr periods were compared to Threshold Limit Values. Four similar exposure groups (SEGs) were created based upon departmental assignment and similarity of work tasks: (1) Administration/Religious Ministries/Legal/Training, (2) Combat Systems/Operations, (3) Medical/Dental, and (4) Supply. Equivalent sound level (Leq) measurements in decibels “A” weighted (dBA) were compared to determine significant differences between each group according to 12-hr on-duty, 12-hr off-duty, and 24-hr periods. Mean 24-hr noise levels ranged from 69–88 dBA with 22% exceeding the 80 dBA Threshold Limit Value. Twelve-hr on-duty noise levels ranged from 71–90 dBA with 17% exceeding the 83 dBA 12-hr on-duty Threshold Limit Value. Twelve-hr off-duty noise exposure ranged from 68–84 dBA with 95% exceeding the 70 dBA American Conference of Governmental Industrial Hygienists threshold classified as effective quiet to allow for temporary threshold shift recovery. Welch Analysis of Variance and Dunnett T3 post hoc tests revealed SEG 2 had significantly higher 24-hr noise exposures than SEG 3 (p = 0.019) and SEG 4 (p = 0.045). SEG 2 had significantly higher 12-hr on-duty noise exposure than SEG 3 (p = 0.030). One Way Analysis of Variance revealed no significant differences between 12-hr off-duty noise exposures according to SEG (p = .096). Some Aircraft Carrier support personnel had 12-hr on-duty and 24-hr noise exposures exceeding Threshold Limit Values with a large proportion exceeding the 70 dBA effective quiet limit during 12-hr off-duty periods. Results suggest personnel that are typically considered low risk for hazardous noise exposure (
Ning Jian-guo - One of the best experts on this subject based on the ideXlab platform.
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Roaming in Virtual Aircraft Carrier Based on Creator/Vega Prime
Computer Simulation, 2007Co-Authors: Ning Jian-guoAbstract:In the development of virtual roaming system,it requires that the model library and rendering software must meet real time.In this paper,contraposing the importance of research on Aircraft Carrier,a way for building virtual Aircraft Carrier roaming is presented.The selection of modeling and rendering tool,some methods of modeling,and optimization of model library etc,are introduced.Special effect node,collision detection,and message hander are used to bring the real effect.At last,by computer hardware,stereo display,man-machine intercommunion,and roaming are achieved.
Jason Ryan - One of the best experts on this subject based on the ideXlab platform.
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validation of an agent based model of Aircraft Carrier flight deck operations
Winter Simulation Conference, 2013Co-Authors: Jason RyanAbstract:In this paper we discuss the validation of an agent-based model of Aircraft Carrier flight deck operations. This model is designed to explore the effects of introducing new unmanned aerial vehicles (UAVs) and related safety protocols into flight deck operations. Validating the system has been challenging, as there is little published information on flight deck operations. Data was assembled from a variety of sources, with the validation process focusing on the simulation's ability to replicate real-world data and that its response to changes in input parameters aligned with observed data and subject matter expert expectations. This poster presents the results of this validation process and discusses features of the simulation that will be added in the future.
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designing an interactive local and global decision support system for Aircraft Carrier deck scheduling
Infotech@Aerospace 2011, 2011Co-Authors: Jason Ryan, M L Cummings, Nicholas Roy, Ashis G Banerjee, Axel SchulteAbstract:In the near future, unmanned aerial vehicles will become part of the naval Aircraft Carrier operating environment. This will add significant complexity to an already highly constrained and dangerous environment. The move towards a shared manned-unmanned environment with an increasing operational tempo in a reduced manning environment will mean more automation is needed in the planning and scheduling of Aircraft, ground vehicles, and crew in these complex environments. However, while automated planning algorithms are fast and able to handle large quantities of information in a short period of time, they are often brittle, unable to cope with changing conditions in highly dynamic environments. Recent research has shown that by allowing high-level interaction between human operators and automated planners, significant increases in overall mission performance can achieved. To this end, a user interface has been developed that allows a human decision maker managing Aircraft Carrier deck operations the ability to interact directly with a centralized planning algorithm for scheduling Aircraft in flight and on the deck (both manned and unmanned), as well as ground vehicles and personnel. This Deck operations Course of Action Planner (DCAP) system leverages the experience and high-level, goal-directed behavior of the human decision maker in conjunction with a powerful automated planning algorithm to develop feasible, robust schedules. This article highlights the design features of DCAP and presents preliminary results from an evaluation designed to quantify the value added by layering in planning and scheduling algorithms into this complex decision process.
Li Hong-xia - One of the best experts on this subject based on the ideXlab platform.
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Computer Simulation of Damage Efficiency for Aircraft Carrier under Attacking of Tactical Ballistic Missile
Computer Simulation, 2006Co-Authors: Li Hong-xiaAbstract:From the point of view of attack-defense of tactical ballistic missile and Aircraft Carrier, and through analyzing the mobile area and scouting early warnings and mobile evading capability of Aircraft Carrier, the tactical ballistic missile’s optimum attack tactics and Aircraft Carrier’s defense tactics were made. Simulation models for the research of damage efficiency for Aircraft Carrier under the attacking of tactical ballistic missile were made, and the structure and function and algorithm were discussed. The imitation result makes down: To static or linear moving Carrier, ordinary ballistic missile processes better hit effect, and yet to the warning system intact and being in mobile evading Carrier, fighting effect is very much finite, so the fresh terminal guidance technology needs to be developed.
