A comparison of reliability and conventional estimation of safe fatigue life and safe inspection intervals

NASA Technical Reports Server (NTRS)

Hooke, F. H.

1972-01-01

Both the conventional and reliability analyses for determining safe fatigue life are predicted on a population having a specified (usually log normal) distribution of life to collapse under a fatigue test load. Under a random service load spectrum, random occurrences of load larger than the fatigue test load may confront and cause collapse of structures which are weakened, though not yet to the fatigue test load. These collapses are included in reliability but excluded in conventional analysis. The theory of risk determination by each method is given, and several reasonably typical examples have been worked out, in which it transpires that if one excludes collapse through exceedance of the uncracked strength, the reliability and conventional analyses gave virtually identical probabilities of failure or survival.

29 CFR 1917.115 - Platforms and skids.

Code of Federal Regulations, 2010 CFR

2010-07-01

... safe condition. Safe working loads, which shall be posted or marked on or adjacent to platforms and... Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... nets, to protect employees against falls. (b) Any employee working below a second-story platform or...

29 CFR 1910.24 - Fixed industrial stairs.

Code of Federal Regulations, 2010 CFR

2010-07-01

... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Walking-Working Surfaces § 1910.24 Fixed industrial stairs. (a... load anticipated but never of less strength than to carry safely a moving concentrated load of 1,000...

Interaction of threat and verbal working memory in adolescents.

PubMed

Patel, Nilam; Vytal, Katherine; Pavletic, Nevia; Stoodley, Catherine; Pine, Daniel S; Grillon, Christian; Ernst, Monique

2016-04-01

Threat induces a state of sustained anxiety that can disrupt cognitive processing, and, reciprocally, cognitive processing can modulate an anxiety response to threat. These effects depend on the level of cognitive engagement, which itself varies as a function of task difficulty. In adults, we recently showed that induced anxiety impaired working memory accuracy at low and medium but not high load. Conversely, increasing the task load reduced the physiological correlates of anxiety (anxiety-potentiated startle). The present work examines such threat-cognition interactions as a function of age. We expected threat to more strongly impact working memory in younger individuals by virtue of putatively restricted cognitive resources and weaker emotion regulation. This was tested by examining the influence of age on the interaction of anxiety and working memory in 25 adolescents (10 to 17 years) and 25 adults (22 to 46 years). Working memory load was manipulated using a verbal n-back task. Anxiety was induced using the threat of an aversive loud scream and measured via eyeblink startle. Findings revealed that, in both age groups, accuracy was lower during threat than safe conditions at low and medium but not high load, and reaction times were faster during threat than safe conditions at high load but did not differ at other loads. Additionally, anxiety-potentiated startle was greater during low and medium than high load. Thus, the interactions of anxiety with working memory appear similar in adolescents and adults. Whether these similarities reflect common neural mechanisms would need to be assessed using functional neuroimaging. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

29 CFR 1910.181 - Derricks.

Code of Federal Regulations, 2010 CFR

2010-07-01

..., working means the external load, in pounds, applied to the derrick, including the weight of load attaching... securely affixed where it is visible to personnel responsible for the safe operation of the equipment. The... of service, and environment, or as specifically indicated below. These inspections shall include the...

30 CFR 75.384 - Longwall and shortwall travelways.

Code of Federal Regulations, 2010 CFR

2010-07-01

... most direct and safe practical route to a designated escapeway. (b) The route of travel shall be clearly marked. (c) When a roof fall or other blockage occurs that prevents travel in the travelway— (1... safe area outby the section loading point; and (3) MSHA shall be notified. (d) Work may resume on the...

29 CFR 1918.87 - Ship's cargo elevators.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Ship's cargo elevators. 1918.87 Section 1918.87 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Handling Cargo § 1918.87 Ship's cargo elevators. (a) Safe working load. The safe workin...

Safety Harness For Work Under Suspended Load

NASA Technical Reports Server (NTRS)

Sunoo, Su Young

1994-01-01

Safety device protects worker under suspended engine or other heavy load. Mechanically linked with load so if load should fall, worker yanked safely away. Worker wears chest-plate vest with straps crossing eye on back. Lower safety cable connected to eye extends horizontally away from worker to nearby wall, wrapped on pulley and extends upward to motion amplifier or reducer. Safety cables transform any sudden downward motion of overhanging load into rapid sideways motion of worker. Net catches worker, preventing worker from bumping against wall.

Engineering Design of Safe Automobile Front Strut Tower Brace with Predetermined Destruction

NASA Astrophysics Data System (ADS)

Mironenko, R. Ye; Balaev, E. Yu; Blednova, Zh M.

2018-03-01

This paper shows the developed design of an automobile front strut tower brace instantly breakable on reaching a predetermined value impact load, which allows the impact load not to be transferred to the opposite strut. An automobile front strut tower brace with the directed destruction V-shaped element using the SolidWorks and SolidWorks Simulations software complex was developed, designed and analyzed. The obtained data were confirmed experimentally. By changing geometric features of the V-shaped element, it is possible to change the impact load value required for its destruction.

29 CFR 1919.77 - Safe working load increase.

Code of Federal Regulations, 2010 CFR

2010-07-01

... or original design limitations unless such increase meets with the manufacturer's approval. Where the manufacturer's services are not available, or where the equipment is of foreign manufacture, engineering design...

A Comparative Study on Safe Pile Capacity as Shown in Table 1 of IS 2911 (Part III): 1980

NASA Astrophysics Data System (ADS)

Pakrashi, Somdev

2017-06-01

Code of practice for design and construction of under reamed pile foundations: IS 2911 (Part-III)—1980 presents one table in respect of safe load for bored cast in situ under reamed piles in sandy and clayey soils including black cotton soils, stem dia. of pile ranging from 20 to 50 cm and its effective length being 3.50 m. A comparative study, was taken up by working out safe pile capacity for one 400 dia., 3.5 m long bored cast in situ under reamed pile based on subsoil properties obtained from soil investigation work as well as subsoil properties of different magnitudes of clayey, sandy soils and comparing the same with the safe pile capacity shown in Table 1 of that IS Code. The study reveals that safe pile capacity computed from subsoil properties, barring a very few cases, considerably differs from that shown in the aforesaid code and looks forward for more research work and study to find out a conclusive explanation of this probable anomaly.

Adaptive Value Normalization in the Prefrontal Cortex Is Reduced by Memory Load.

PubMed

Holper, L; Van Brussel, L D; Schmidt, L; Schulthess, S; Burke, C J; Louie, K; Seifritz, E; Tobler, P N

2017-01-01

Adaptation facilitates neural representation of a wide range of diverse inputs, including reward values. Adaptive value coding typically relies on contextual information either obtained from the environment or retrieved from and maintained in memory. However, it is unknown whether having to retrieve and maintain context information modulates the brain's capacity for value adaptation. To address this issue, we measured hemodynamic responses of the prefrontal cortex (PFC) in two studies on risky decision-making. In each trial, healthy human subjects chose between a risky and a safe alternative; half of the participants had to remember the risky alternatives, whereas for the other half they were presented visually. The value of safe alternatives varied across trials. PFC responses adapted to contextual risk information, with steeper coding of safe alternative value in lower-risk contexts. Importantly, this adaptation depended on working memory load, such that response functions relating PFC activity to safe values were steeper with presented versus remembered risk. An independent second study replicated the findings of the first study and showed that similar slope reductions also arose when memory maintenance demands were increased with a secondary working memory task. Formal model comparison showed that a divisive normalization model fitted effects of both risk context and working memory demands on PFC activity better than alternative models of value adaptation, and revealed that reduced suppression of background activity was the critical parameter impairing normalization with increased memory maintenance demand. Our findings suggest that mnemonic processes can constrain normalization of neural value representations.

Facility or Facilities? That is the Question.

NASA Astrophysics Data System (ADS)

Viso, M.

2018-04-01

The management of the martian samples upon arrival on the Earth will require a lot of work to ensure a safe life detection and biohazard testing during the quarantine. This will induce a sharing of the load between several facilities.

Study on load test of 100m cross-reinforced deck type concrete box arch bridge

NASA Astrophysics Data System (ADS)

Shi, Jing Xian; Cheng, Ying Jie

2018-06-01

Found in the routine quality inspection of highway bridge that many vertical fractures on the main beam (10mT beam) of the steel reinforced concrete arch bridge near the hydropower station. In order to grasp the bearing capacity of this bridge under working conditions with cracks, the static load and dynamic load test of box arch bridge are carried out. The Midas civil theory is calculated by using the special plate trailer - 300 as the calculation load, and the deflection and stress of the critical section are tested by the equivalent cloth load in the test vehicle. The pulsation test, obstacles and no obstacle driving test were carried out. Experimental results show that the bridge under the condition of the test loads is in safe condition, main bearing component of the strength and stiffness meet the design requirements, the crack width does not increase, in the process of loading bridge overall work performance is good.

29 CFR 1919.21 - Marking and posting of safe working loads.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the capacity of the boom of a crane or derrick has been or will be rated in accordance with the... controls and visible to the crane operator. Ratings may be stated in pounds. When they are stated in tons...

29 CFR 1919.21 - Marking and posting of safe working loads.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the capacity of the boom of a crane or derrick has been or will be rated in accordance with the... controls and visible to the crane operator. Ratings may be stated in pounds. When they are stated in tons...

Adaptive Value Normalization in the Prefrontal Cortex Is Reduced by Memory Load

PubMed Central

Burke, C. J.; Seifritz, E.; Tobler, P. N.

2017-01-01

Abstract Adaptation facilitates neural representation of a wide range of diverse inputs, including reward values. Adaptive value coding typically relies on contextual information either obtained from the environment or retrieved from and maintained in memory. However, it is unknown whether having to retrieve and maintain context information modulates the brain’s capacity for value adaptation. To address this issue, we measured hemodynamic responses of the prefrontal cortex (PFC) in two studies on risky decision-making. In each trial, healthy human subjects chose between a risky and a safe alternative; half of the participants had to remember the risky alternatives, whereas for the other half they were presented visually. The value of safe alternatives varied across trials. PFC responses adapted to contextual risk information, with steeper coding of safe alternative value in lower-risk contexts. Importantly, this adaptation depended on working memory load, such that response functions relating PFC activity to safe values were steeper with presented versus remembered risk. An independent second study replicated the findings of the first study and showed that similar slope reductions also arose when memory maintenance demands were increased with a secondary working memory task. Formal model comparison showed that a divisive normalization model fitted effects of both risk context and working memory demands on PFC activity better than alternative models of value adaptation, and revealed that reduced suppression of background activity was the critical parameter impairing normalization with increased memory maintenance demand. Our findings suggest that mnemonic processes can constrain normalization of neural value representations. PMID:28462394

The Inclusion of Arbitrary Load Histories in the Strength Decay Model for Stress Rupture

NASA Technical Reports Server (NTRS)

Reeder, James R.

2014-01-01

Stress rupture is a failure mechanism where failures can occur after a period of time, even though the material has seen no increase in load. Carbon/epoxy composite materials have demonstrated the stress rupture failure mechanism. In a previous work, a model was proposed for stress rupture of composite overwrap pressure vessels (COPVs) and similar composite structures based on strength degradation. However, the original model was limited to constant load periods (holds) at constant load. The model was expanded in this paper to address arbitrary loading histories and specifically the inclusions of ramp loadings up to holds and back down. The broadening of the model allows for failures on loading to be treated as any other failure that may occur during testing instead of having to be treated as a special case. The inclusion of ramps can also influence the length of the "safe period" following proof loading that was previously predicted by the model. No stress rupture failures are predicted in a safe period because time is required for strength to decay from above the proof level to the lower level of loading. Although the model can predict failures during the ramp periods, no closed-form solution for the failure times could be derived. Therefore, two suggested solution techniques were proposed. Finally, the model was used to design an experiment that could detect the difference between the strength decay model and a commonly used model for stress rupture. Although these types of models are necessary to help guide experiments for stress rupture, only experimental evidence will determine how well the model may predict actual material response. If the model can be shown to be accurate, current proof loading requirements may result in predicted safe periods as long as 10(13) years. COPVs design requirements for stress rupture may then be relaxed, allowing more efficient designs, while still maintaining an acceptable level of safety.

29 CFR 1919.13 - General.

Code of Federal Regulations, 2010 CFR

2010-07-01

.... Where no design data on which to base a rating is obtainable, the safe working load ratings assigned... 29 Labor 7 2010-07-01 2010-07-01 false General. 1919.13 Section 1919.13 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED...

[Risk assessment of manual handling of loads: the choice of reference values in light of Leg. 81/2008].

PubMed

Baracco, A; Coggiola, M; Discalzi, G; Perrelli, F; Romano, C

2009-01-01

Italian law on safety at work does not clarify specific levels of load for safe manual material handling. For this reason professionals appointed for safety need to define new target range value for the correct application of D.Lgs. 81/2008 law. Authors, discussing about indication of the national laws and international rules, suggest the assumption of a load of 25 and 20 kg as reference values for male and female adult and healthy workers. They also examine the graduation of the acceptable loads in relation to workers' age and the Lifting Index values to be adopted as action limit and exposure limit.

76 FR 38074 - Airworthiness Directives; The Boeing Company Model 747-100, 747-100B, 747-200B, 747-200C, 747...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-29

... withstand fail-safe loads. DATES: We must receive comments on this proposed AD by August 15, 2011. ADDRESSES... pressurization and the inability of the airplane fuselage to withstand fail-safe loads. Actions Since Existing AD... withstand fail-safe loads. Compliance (f) You are responsible for having the actions required by this AD...

29 CFR 1919.31 - Proof tests-loose gear.

Code of Federal Regulations, 2013 CFR

2013-07-01

... safe working load. Hand-operated blocks used with pitched chains and rings, hooks, shackles or swivels... (a) of this section, and before being taken into use, all chains, rings, hooks, shackles, blocks or... Persons § 1919.31 Proof tests—loose gear. (a) Chains, rings, shackles and other loose gear (whether...

29 CFR 1919.31 - Proof tests-loose gear.

Code of Federal Regulations, 2011 CFR

2011-07-01

... safe working load. Hand-operated blocks used with pitched chains and rings, hooks, shackles or swivels... (a) of this section, and before being taken into use, all chains, rings, hooks, shackles, blocks or... Persons § 1919.31 Proof tests—loose gear. (a) Chains, rings, shackles and other loose gear (whether...

29 CFR 1919.31 - Proof tests-loose gear.

Code of Federal Regulations, 2014 CFR

2014-07-01

... safe working load. Hand-operated blocks used with pitched chains and rings, hooks, shackles or swivels... (a) of this section, and before being taken into use, all chains, rings, hooks, shackles, blocks or... Persons § 1919.31 Proof tests—loose gear. (a) Chains, rings, shackles and other loose gear (whether...

29 CFR 1919.31 - Proof tests-loose gear.

Code of Federal Regulations, 2010 CFR

2010-07-01

... safe working load. Hand-operated blocks used with pitched chains and rings, hooks, shackles or swivels... (a) of this section, and before being taken into use, all chains, rings, hooks, shackles, blocks or... Persons § 1919.31 Proof tests—loose gear. (a) Chains, rings, shackles and other loose gear (whether...

29 CFR 1919.31 - Proof tests-loose gear.

Code of Federal Regulations, 2012 CFR

2012-07-01

... safe working load. Hand-operated blocks used with pitched chains and rings, hooks, shackles or swivels... (a) of this section, and before being taken into use, all chains, rings, hooks, shackles, blocks or... Persons § 1919.31 Proof tests—loose gear. (a) Chains, rings, shackles and other loose gear (whether...

Analysis of Skeletal Muscle Metrics as Predictors of Functional Task Performance

NASA Technical Reports Server (NTRS)

Ryder, Jeffrey W.; Buxton, Roxanne E.; Redd, Elizabeth; Scott-Pandorf, Melissa; Hackney, Kyle J.; Fiedler, James; Ploutz-Snyder, Robert J.; Bloomberg, Jacob J.; Ploutz-Snyder, Lori L.

2010-01-01

PURPOSE: The ability to predict task performance using physiological performance metrics is vital to ensure that astronauts can execute their jobs safely and effectively. This investigation used a weighted suit to evaluate task performance at various ratios of strength, power, and endurance to body weight. METHODS: Twenty subjects completed muscle performance tests and functional tasks representative of those that would be required of astronauts during planetary exploration (see table for specific tests/tasks). Subjects performed functional tasks while wearing a weighted suit with additional loads ranging from 0-120% of initial body weight. Performance metrics were time to completion for all tasks except hatch opening, which consisted of total work. Task performance metrics were plotted against muscle metrics normalized to "body weight" (subject weight + external load; BW) for each trial. Fractional polynomial regression was used to model the relationship between muscle and task performance. CONCLUSION: LPMIF/BW is the best predictor of performance for predominantly lower-body tasks that are ambulatory and of short duration. LPMIF/BW is a very practical predictor of occupational task performance as it is quick and relatively safe to perform. Accordingly, bench press work best predicts hatch-opening work performance.

Dynamic Structural Fault Detection and Identification

NASA Technical Reports Server (NTRS)

Smith, Timothy; Reichenbach, Eric; Urnes, James M.

2009-01-01

Aircraft structures are designed to guarantee safety of flight in some required operational envelope. When the aircraft becomes structurally impaired, safety of flight may not be guaranteed within that previously safe operational envelope. In this case the safe operational envelope must be redefined in-flight and a means to prevent excursion from this new envelope must be implemented. A specific structural failure mode that may result in a reduced safe operating envelope, the exceedance of which could lead to catastrophic structural failure of the aircraft, will be addressed. The goal of the DFEAP program is the detection of this failure mode coupled with flight controls adaptation to limit critical loads in the damaged aircraft structure. The DFEAP program is working with an F/A-18 aircraft model. The composite wing skins are bonded to metallic spars in the wing substructure. Over time, it is possible that this bonding can deteriorate due to fatigue. In this case, the ability of the wing spar to transfer loading between the wing skins is reduced. This failure mode can translate to a reduced allowable compressive strain on the wing skin and could lead to catastrophic wing buckling if load limiting of the wing structure is not applied. The DFEAP program will make use of a simplified wing strain model for the healthy aircraft. The outputs of this model will be compared in real-time to onboard strain measurements at several locations on the aircraft wing. A damage condition is declared at a given location when the strain measurements differ sufficiently from the strain model. Parameter identification of the damaged structure wing strain parameters will be employed to provide load limiting control adaptation for the aircraft. This paper will discuss the simplified strain models used in the implementation and their interaction with the strain sensor measurements. Also discussed will be the damage detection and identification schemes employed and the means by which the damaged aircraft parameters will be used to provide load limiting that keeps the aircraft within the safe operational envelope.

[Thermal load at workstations in the underground coal mining: Results of research carried out in 6 coal mines].

PubMed

Słota, Krzysztof; Słota, Zbigniew; Kułagowska, Ewa

Statistics shows that almost half of Polish extraction in underground mines takes place at workstations where temperature exceeds 28°C. The number of employees working in such conditions is gradually increasing, therefore, the problem of safety and health protection is still growing. In the present study we assessed the heat load of employees at different workstations in the mining industry, taking into account current thermal conditions and work costs. The evaluation of energy cost of work was carried out in 6 coal mines. A total of 221 miners employed at different workstations were assessed. Individual groups of miners were characterized and thermal safety of the miners was assessed relying on thermal discomfort index. The results of this study indicate considerable differences in the durations of analyzed work processes at individual workstations. The highest average energy cost was noted during the work performed in the forehead. The lowest value was found in the auxiliary staff. The calculated index of discomfort clearly indicated numerous situations in which the admissible range of thermal load exceeded the parameters of thermal load safe for human health. It should be noted that the values of average labor cost fall within the upper, albeit admissible, limits of thermal load. The results of the study indicate that in some cases work in mining is performed in conditions of thermal discomfort. Due to high variability and complexity of work conditions it becomes necessary to verify the workers' load at different workstations, which largely depends on the environmental conditions and work organization, as well as on the performance of workers themselves. Med Pr 2016;67(4):477-498. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

Rotating assembly working group summary

NASA Technical Reports Server (NTRS)

Kulkarni, S. V.

1984-01-01

The feasibility of a fail safe flywheel system was demonstrated. Three of the major advantages of flywheel systems are: longer operational life, higher electrical efficiency, and higher system energy density. The use of composite material flywheels is important to realize these advantages. Rotor design and dynamics, rotor materials and fabrication, safety, nondestructive testing, and systems operation loads and environment, are outlined.

Extended Aging Theories for Predictions of Safe Operational Life of Critical Airborne Structural Components

NASA Technical Reports Server (NTRS)

Ko, William L.; Chen, Tony

2006-01-01

The previously developed Ko closed-form aging theory has been reformulated into a more compact mathematical form for easier application. A new equivalent loading theory and empirical loading theories have also been developed and incorporated into the revised Ko aging theory for the prediction of a safe operational life of airborne failure-critical structural components. The new set of aging and loading theories were applied to predict the safe number of flights for the B-52B aircraft to carry a launch vehicle, the structural life of critical components consumed by load excursion to proof load value, and the ground-sitting life of B-52B pylon failure-critical structural components. A special life prediction method was developed for the preflight predictions of operational life of failure-critical structural components of the B-52H pylon system, for which no flight data are available.

29 CFR 1919.14 - Initial tests of cargo gear and tests after alterations, renewals or repairs.

Code of Federal Regulations, 2010 CFR

2010-07-01

... components, a test as required in paragraph (a)(1) of this section shall be carried out. (d) If the operation in which cargo gear is engaged never utilizes more than a fraction of the safe working load rating, the owner may, at his option, have said gear certificated for, and limited in operation to, a lesser...

29 CFR Appendix IV to Part 1918 - Special Cargo Gear and Container Spreader Test Requirements (Mandatory) [see § 1918.61 (f), (g...

Code of Federal Regulations, 2011 CFR

2011-07-01

... (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH.... Safe Working Load—greater than 5 short tons (10,000 lbs./4.5 metric tons) Prior to initial use OSHA... 50 short tons 5 short tons in excess of SWL. Every four years after initial proof load test OSHA...

29 CFR Appendix IV to Part 1918 - Special Cargo Gear and Container Spreader Test Requirements (Mandatory) [see § 1918.61 (f), (g...

Code of Federal Regulations, 2010 CFR

2010-07-01

... (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH.... Safe Working Load—greater than 5 short tons (10,000 lbs./4.5 metric tons) Prior to initial use OSHA... 50 short tons 5 short tons in excess of SWL. Every four years after initial proof load test OSHA...

Studies on thermo-elastic heating of horns used in ultrasonic plastic welding.

PubMed

Roopa Rani, M; Prakasan, K; Rudramoorthy, R

2015-01-01

Ultrasonic welding horn is half wavelength section or tool used to focus the ultrasonic vibrations to the components being welded. The horn is designed in such a way that it maximizes the amplitude of the sound wave passing through it. The ends of the horn represent the displacement anti-nodes and the center the 'node' of the wave. As the horns perform 20,000 cycles of expansion and contraction per second, they are highly stressed at the nodes and are heated owing to thermo-elastic effects. Considerable temperature rise may be observed in the horn, at the nodal region when working at high amplitudes indicating high stress levels leading to failure of horns due to cyclic loading. The limits for amplitude must therefore be evaluated for the safe working of the horn. Horns made of different materials have different thermo-elastic behaviors and hence different temperatures at the nodes and antinodes. This temperature field can be used as a control mechanism for setting the amplitude/weld parameters. Safe stress levels can be predicted using modal and harmonic analyses followed by a stress analysis to study the effect of cyclic loads. These are achieved using 'Ansys'. The maximum amplitude level obtained from the stress analysis is used as input for 'Comsol' to predict the temperature field. The actual temperature developed in the horn during operation is measured using infrared camera and compared with the simulated temperature. From experiments, it is observed that horn made of titanium had the lowest temperature rise at the critical region and can be expected to operate at amplitudes up to 77 μm without suffering failure due to cyclic loading. The method of predicting thermo-elastic stresses and temperature may be adopted by the industry for operating the horn within the safe stress limits thereby extending the life of the horn. Copyright © 2014 Elsevier B.V. All rights reserved.

77 FR 29857 - Airworthiness Directives; The Boeing Company Airplanes

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-21

... of cabin pressurization and the inability of the fuselage to withstand fail-safe loads. DATES: This... cabin pressurization and the inability of the fuselage to withstand fail-safe loads. (f) Compliance You... reference of certain publications listed in the AD as of June 25, 2012. ADDRESSES: For service information...

Predicting the safe load on backpacker's arm using Lagrange multipliers method

NASA Astrophysics Data System (ADS)

Abdalla, Faisal Saleh; Rambely, Azmin Sham

2014-09-01

In this study, a technique has been suggested to reduce a backpack load by transmitting determined loads to the children arm. The purpose of this paper is to estimate school children arm muscles while load carriage as well as to determine the safe load can be carried at wrist while walking with backpack. A mathematical model, as three DOFs model, was investigated in the sagittal plane and Lagrange multipliers method (LMM) was utilized to minimize a quadratic objective function of muscle forces. The muscle forces were minimized with three different load conditions which are termed as 0-L=0 N, 1-L=21.95 N, and 2-L=43.9 N. The investigated muscles were estimated and compared to their maximum forces throughout the load conditions. Flexor and extensor muscles were estimated and the results showed that flexor muscles were active while extensor muscles showed inactivity. The estimated muscle forces were didn't exceed their maximum forces with 0-L and 1-L conditions whereas biceps and FCR muscles exceeded their maximum forces with 2-L condition. Consequently, 1-L condition is quiet safe to be carried by hand whereas 2-L condition is not. Thus to reduce the load in the backpack the transmitted load shouldn't exceed 1-L condition.

Structural Load Alleviation Applied to Next Generation Aircraft and Wind Turbines

NASA Technical Reports Server (NTRS)

Frost, Susan

2011-01-01

Reducing the environmental impact of aviation is a goal of the Subsonic Fixed Wing Project under the Fundamental Aeronautics Program of NASAs Aeronautics Research Mission Directorate. Environmental impact of aviation is being addressed by novel aircraft configurations and materials that reduce aircraft weight and increase aerodynamic efficiency. NASA is developing tools to address the challenges of increased airframe flexibility created by wings constructed with reduced structural material and novel light-weight materials. This talk will present a framework and demonstration of a flight control system using optimal control allocation with structural load feedback and constraints to achieve safe aircraft operation. As wind turbines age, they become susceptible to many forms of blade degradation. Results will be presented on work in progress that uses adaptive contingency control for load mitigation in a wind turbine simulation with blade damage progression modeled.

29 CFR 1910.179 - Overhead and gantry cranes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... adequately guarded or isolated. (40) Fail-safe means a provision designed to automatically stop or safely... shall be capable of maintaining safe lowering speeds of rated loads. (ii) The control braking means... the crane operator. (viii) Automatic cranes shall be so designed that all motions shall fail-safe if...

Assessing the influence of a passive, upper extremity exoskeletal vest for tasks requiring arm elevation: Part II - "Unexpected" effects on shoulder motion, balance, and spine loading.

PubMed

Kim, Sunwook; Nussbaum, Maury A; Mokhlespour Esfahani, Mohammad Iman; Alemi, Mohammad Mehdi; Jia, Bochen; Rashedi, Ehsan

2018-03-07

Adopting a new technology (exoskeletal vest designed to support overhead work) in the workplace can be challenging since the technology may pose unexpected safety and health consequences. A prototype exoskeletal vest was evaluated for potential unexpected consequences with a set of evaluation tests for: usability (especially, donning & doffing), shoulder range of motion (ROM), postural control, slip & trip risks, and spine loading during overhead work simulations. Donning/doffing the vest was easily done by a wearer alone. The vest reduced the max. shoulder abduction ROM by ∼10%, and increased the mean center of pressure velocity in the anteroposterior direction by ∼12%. However, vest use had minimal influences on trip-/slip-related fall risks during level walking, and significantly reduced spine loadings (up to ∼30%) especially during the drilling task. Use of an exoskeletal vest can be beneficial, yet the current evaluation tests should be expanded for more comprehensiveness, to enable the safe adoption of the technology. Copyright © 2018 Elsevier Ltd. All rights reserved.

Safe Minimum Internal Temperature Chart

MedlinePlus

... Administrative Forms Standard Forms Skip Navigation Z7_0Q0619C0JGR010IFST1G5B10H1 Web Content Viewer (JSR 286) Actions ${title} Loading... / Topics / ... Chart / Safe Minimum Internal Temperature Chart Z7_0Q0619C0JGR010IFST1G5B10H3 Web Content Viewer (JSR 286) Actions ${title} Loading... Z7_ ...

A Procedure for Setting Environmentally Safe Total Maximum Daily Loads (TMDLs) for Selenium

Treesearch

A. Dennis Lemly

2002-01-01

This article presents a seven-step procedure for developing environmentally safe total maximum daily loads (TMDLs) for selenium. The need for this information stems from recent actions taken by the U.S. Environmental Protection Agency (EPA) that may require TMDLs for selenium and other contaminants that are impairing water bodies. However, there is no technical...

Photoenhanced gene transfection by a curcumin loaded CS-g-PZLL micelle.

PubMed

Lin, Jian-Tao; Pan, Wen-Jia; Zhang, Jun-Ai; Wang, Wei; Zhong, Jia; Su, Jia-Min; Li, Tong; Zou, Ying; Wang, Guan-Hai

2017-09-01

The codelivery of drug and gene is a promising method for cancer treatment. In our previous works, we prepared a cationic micelles based on chitosan and poly-(N-3-carbobenzyloxylysine) (CS-g-PZLL), but transfection ratio of CS-g-PZLL to Hela cell was low. Herein, to improve the transfection efficiency of CS-g-PZLL, curcumin was loaded in the CS-g-PZLL micelle. After irradiation, the obtained curcumin loaded micelle showed a better transfection, and the p53 protein expression in Hela cells was higher. The apoptosis assay showed that the complex could induce a more significant apoptosis to Hela cells than that of curcumin or p53 used alone, and the curcumin loaded micelle inducing apoptosis was best after irradiation. Therefore, CS-g-PZLL is a safe and effective carrier for the codelivery of drug/gene, and curcumin could be used as a photosensitizer to induce a photoenhanced gene transfection, which should be encouraged in improving transfection and tumor therapy. Copyright © 2017. Published by Elsevier B.V.

Dragon Operations: Hostage Rescues in the Congo, 1964-1965 (Leavenworth Papers, Number 14)

DTIC Science & Technology

1988-01-01

lying in the street. 28 The corpse of Dr. Carlson 103 Off-loading medical supplies and food at Stanley.ville The paras’ assembly of the survivors was...attempted to care for the refugees- providing food , water, and shelter from rebel fire-Strobaugh and the · Belgians worked feverishly to get them safely...Georges Ledant, Colonel e.r. Belgian Army, interviews with the author, Ville Franche , France, 9 January 1986: Vandewalle interviews; and Janssens

Review of load rating and posting procedures and requirements.

DOT National Transportation Integrated Search

2014-12-01

All states are required to load rate and post bridges in order to comply with federal standards. Load ratings are performed in order to : determine the safe live load capacity of a bridge, considering the existing conditions of the bridge. Based on t...

Debris flow impact estimation on a rigid barrier

NASA Astrophysics Data System (ADS)

Vagnon, Federico; Segalini, Andrea

2016-07-01

The aim of this paper is to analyse debris flow impact against rigid and undrained barrier in order to propose a new formulation for the estimation of acting force after the flow impact to safe design protection structures. For this reason, this work concentrates on the flow impact, by performing a series of small scale tests in a specifically created flume. Flow characteristics (flow height and velocity) and applied loads (dynamic and static) on barrier were measured using four ultrasonic devices, four load cells and a contact surface pressure gauge. The results obtained were compared with main existing models and a new equation is proposed. Furthermore, a brief review of the small scale theory was provided to analyse the scale effects that can affect the results.

A physical workload index to evaluate a safe resident handling program for nursing home personnel.

PubMed

Kurowski, Alicia; Buchholz, Bryan; Punnett, Laura

2014-06-01

The aim of this study was to obtain a comprehensive analysis of the physical workload of clinical staff in long-term care facilities, before and after a safe resident handling program (SRHP). Ergonomic exposures of health care workers include manual handling of patients and many non-neutral postures. A comprehensive assessment requires the integration of loads from these varied exposures into a single metric. The Postures, Activities, Tools, and Handling observational protocol, customized for health care, was used for direct observations of ergonomic exposures in clinical jobs at 12 nursing homes before the SRHP and 3, 12, 24, and 36 months afterward. Average compressive forces on the spine were estimated for observed combinations of body postures and manual handling and then weighted by frequencies of observed time for the combination. These values were summed to obtain a biomechanical index for nursing assistants and nurses across observation periods. The physical workload index (PWI) was much higher for nursing assistants than for nurses and decreased more after 3 years (-24% versus -2.5%). Specifically during resident handling, the PWI for nursing assistants decreased by 41% of baseline value. Spinal loading was higher for nursing assistants than for nurses in long-term care centers. Both job groups experienced reductions in physical loading from the SRHP, especially the nursing assistants and especially while resident handling. The PWI facilitates a comprehensive investigation of physical loading from both manual handling and non-neutral postures. It can be used in any work setting to identify high-risk tasks and determine whether reductions in one exposure are offset by increases in another.

Development of safe infrared gas lasers

NASA Astrophysics Data System (ADS)

Mainuddin; Singhal, Gaurav; Tyagi, R. K.; Maini, A. K.

2013-04-01

Infrared gas lasers find application in numerous civil and military areas. Such lasers are therefore being developed at different institutions around the world. However, the development of chemical infrared gas lasers such as chemical oxygen iodine lasers (COIL) involves the use of several hazardous chemicals. In order to exploit full potential of these lasers, one must take diligent care of the safety issues associated with the handling of these chemicals and the involved processes. The present paper discusses the safety aspects to be taken into account in the development of these infrared gas lasers including various detection sensors working in conjunction with a customized data acquisition system loaded with safety interlocks for safe operation. The developed safety schemes may also be implemented for CO2 gas dynamic laser (GDL) and hydrogen fluoride-deuterium fluoride (HF-DF) Laser.

Vibration analysis in reciprocating compressors

NASA Astrophysics Data System (ADS)

Kacani, V.

2017-08-01

This paper presents the influence of modelling on the mechanical natural frequencies, the effect of inertia loads on the structure vibration, the impact of the crank gear damping on speed fluctuation to ensure a safe operation and increasing the reliability of reciprocating compressors. In this paper it is shown, that conventional way of modelling is not sufficient. For best results it is required to include the whole system (bare block, frame, coupling, main driver, vessels, pipe work, etc.) in the model (see results in Table 1).

14 CFR 23.775 - Windshields and windows.

Code of Federal Regulations, 2011 CFR

2011-01-01

... loadings and flight loads, or compliance with the fail-safe requirements of paragraph (d) of this section... loads combined with critical aerodynamic pressure and temperature effects, after failure of any load... in front of the pilots must be arranged so that, assuming the loss of vision through any one panel...

14 CFR 23.775 - Windshields and windows.

Code of Federal Regulations, 2010 CFR

2010-01-01

... loadings and flight loads, or compliance with the fail-safe requirements of paragraph (d) of this section... loads combined with critical aerodynamic pressure and temperature effects, after failure of any load... in front of the pilots must be arranged so that, assuming the loss of vision through any one panel...

14 CFR 23.775 - Windshields and windows.

Code of Federal Regulations, 2014 CFR

2014-01-01

... loadings and flight loads, or compliance with the fail-safe requirements of paragraph (d) of this section... loads combined with critical aerodynamic pressure and temperature effects, after failure of any load... in front of the pilots must be arranged so that, assuming the loss of vision through any one panel...

14 CFR 23.775 - Windshields and windows.

Code of Federal Regulations, 2013 CFR

2013-01-01

... loadings and flight loads, or compliance with the fail-safe requirements of paragraph (d) of this section... loads combined with critical aerodynamic pressure and temperature effects, after failure of any load... in front of the pilots must be arranged so that, assuming the loss of vision through any one panel...

14 CFR 23.775 - Windshields and windows.

Code of Federal Regulations, 2012 CFR

2012-01-01

... loadings and flight loads, or compliance with the fail-safe requirements of paragraph (d) of this section... loads combined with critical aerodynamic pressure and temperature effects, after failure of any load... in front of the pilots must be arranged so that, assuming the loss of vision through any one panel...

Pushover, Response Spectrum and Time History Analyses of Safe Rooms in a Poor Performance Masonry Building

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mazloom, M.

2008-07-08

The idea of safe room has been developed for decreasing the earthquake casualties in masonry buildings. The information obtained from the previous ground motions occurring in seismic zones expresses the lack of enough safety of these buildings against earthquakes. For this reason, an attempt has been made to create some safe areas inside the existing masonry buildings, which are called safe rooms. The practical method for making these safe areas is to install some prefabricated steel frames in some parts of the existing structure. These frames do not carry any service loads before an earthquake. However, if a devastating earthquakemore » happens and the load bearing walls of the building are destroyed, some parts of the floors, which are in the safe areas, will fall on the roof of the installed frames and the occupants who have sheltered there will survive. This paper presents the performance of these frames located in a destroying three storey masonry building with favorable conclusions. In fact, the experimental pushover diagram of the safe room located at the ground-floor level of this building is compared with the analytical results and it is concluded that pushover analysis is a good method for seismic performance evaluation of safe rooms. For time history analysis the 1940 El Centro, the 2003 Bam, and the 1990 Manjil earthquake records with the maximum peak accelerations of 0.35g were utilized. Also the design spectrum of Iranian Standard No. 2800-05 for the ground kind 2 is used for response spectrum analysis. The results of time history, response spectrum and pushover analyses show that the strength and displacement capacity of the steel frames are adequate to accommodate the distortions generated by seismic loads and aftershocks properly.« less

45 CFR 1310.17 - Driver and bus monitor training.

Code of Federal Regulations, 2010 CFR

2010-10-01

... safe and efficient manner; (2) safely run a fixed route, including loading and unloading children... first aid in case of injury; (4) handle emergency situations, including vehicle evacuation procedures...

Strength and life criteria for corrugated fiberboard by three methods

Treesearch

Thomas J. Urbanik

1997-01-01

The conventional test method for determining the stacking life of corrugated containers at a fixed load level does not adequately predict a safe load when storage time is fixed. This study introduced multiple load levels and related the probability of time at failure to load. A statistical analysis of logarithm-of-time failure data varying with load level predicts the...

Carbohydrate-Loading: A Safe and Effective Method of Improving Endurance Performance.

ERIC Educational Resources Information Center

Beeker, Richard T.; Israel, Richard G.

Carbohydrate-loading prior to distance events is a common practice among endurance athletes. The purposes of this paper are to review previous research and to clarify misconceptions which may exist concerning carbohydrate-loading. The most effective method of carbohydrate-loading involves a training run of sufficient intensity and duration to…

24 CFR 3285.303 - Piers.

Code of Federal Regulations, 2011 CFR

2011-04-01

... must be capable of transmitting the vertical live and dead loads to the footings or foundation. (b... dimensions of the home, the design dead and live loads, the spacing of the piers, and the way the piers are... to the loads required to safely support the dead and live loads, as required by § 3285.301, and the...

24 CFR 3285.303 - Piers.

Code of Federal Regulations, 2010 CFR

2010-04-01

... must be capable of transmitting the vertical live and dead loads to the footings or foundation. (b... dimensions of the home, the design dead and live loads, the spacing of the piers, and the way the piers are... to the loads required to safely support the dead and live loads, as required by § 3285.301, and the...

24 CFR 3285.303 - Piers.

Code of Federal Regulations, 2014 CFR

2014-04-01

... must be capable of transmitting the vertical live and dead loads to the footings or foundation. (b... dimensions of the home, the design dead and live loads, the spacing of the piers, and the way the piers are... to the loads required to safely support the dead and live loads, as required by § 3285.301, and the...

24 CFR 3285.303 - Piers.

Code of Federal Regulations, 2012 CFR

2012-04-01

... must be capable of transmitting the vertical live and dead loads to the footings or foundation. (b... dimensions of the home, the design dead and live loads, the spacing of the piers, and the way the piers are... to the loads required to safely support the dead and live loads, as required by § 3285.301, and the...

24 CFR 3285.303 - Piers.

Code of Federal Regulations, 2013 CFR

2013-04-01

... must be capable of transmitting the vertical live and dead loads to the footings or foundation. (b... dimensions of the home, the design dead and live loads, the spacing of the piers, and the way the piers are... to the loads required to safely support the dead and live loads, as required by § 3285.301, and the...

Trailing Vortex-Induced Loads During Close Encounters in Cruise

NASA Technical Reports Server (NTRS)

Mendenhall, Michael R.; Lesieutre, Daniel J; Kelly, Michael J.

2015-01-01

The trailing vortex induced aerodynamic loads on a Falcon 20G business jet flying in the wake of a DC-8 are predicted to provide a preflight estimate of safe trail distances during flight test measurements in the wake. Static and dynamic loads on the airframe flying in the near wake are shown at a matrix of locations, and the dynamic motion of the Falcon 20G during traverses of the DC-8 primary trailing vortex is simulated. Safe trailing distances for the test flights are determined, and optimum vortex traverse schemes are identified to moderate the motion of the trailing aircraft during close encounters with the vortex wake.

Some considerations in the design of transport aircraft /The W. Rupert Turnbull Lecture for 1975/

NASA Technical Reports Server (NTRS)

Jones, R. T.

1975-01-01

The slow landing speeds (30 mph, 65 mph) and light wing loading required for safety in the early days of aviation are shown to be irrelevant to safe landings of propeller-driven aircraft, while increases in wing loading and landing speed have been accompanied by improved safety records. This is attributed to length of runway and time available for approach maneuvers, plus immunity to wind gusts and turbulence conferred by higher wing loadings. Aerodynamical and mechanical aspects of safe landing are discussed, with no mention of instruments. Fuel savings achievable through high aspect ratio, variable sweep angle, and supercritical airfoils are also considered.

A facile doxorubicin-dichloroacetate conjugate nanomedicine with high drug loading for safe drug delivery.

PubMed

Yang, Conglian; Wu, Tingting; Qin, Yuting; Qi, Yan; Sun, Yu; Kong, Miao; Jiang, Xue; Qin, Xianya; Shen, Yaqi; Zhang, Zhiping

2018-01-01

Doxorubicin (DOX) is an effective chemotherapeutic agent but severe side effects limit its clinical application. Nanoformulations can reduce the toxicity while still have various limitations, such as complexity, low drug loading capability and excipient related concerns. An amphiphilic conjugate, doxorubicin-dichloroacetate, was synthesized and the corresponding nanoparticles were prepared. The in vitro cytotoxicity and intracellular uptake, in vivo imaging, antitumor effects and systemic toxicities of nanoparticles were carried out to evaluate the therapeutic efficiency of tumor. Doxorubicin-dichloroacetate conjugate can self-assemble into nanoparticles with small amount of DSPE-PEG 2000 , leading to high drug loading (71.8%, w/w) and diminished excipient associated concerns. The nanoparticles exhibited invisible systemic toxicity and high maximum tolerated dose of 75 mg DOX equiv./kg, which was 15-fold higher than that of free DOX. It also showed good tumor targeting capability and enhanced antitumor efficacy in murine melanoma model. This work provides a promising strategy to simplify the drug preparation process, increase drug loading content, reduce systemic toxicity as well as enhance antitumor efficiency.

A discussion on turbine design for safe operation

NASA Astrophysics Data System (ADS)

Brekke, H.

2012-11-01

The paper gives a brief description of the hydraulic design of Francis and Pelton runners. The dynamic behaviour at part load has been a major problem for low head and medium head Francis turbines. The main reason for this has been inter blade separation and unstable swirl flow in the draft tube. A description is given on the hydraulic design of X-BLADE runners to obtain stable operation on the whole range of operation by reducing the cross flow. A classical theoretical analysis is also given on the dynamic hydraulic load on Pelton buckets. Several CFD analyses of this non stationary flow have been presented during the last decade, but the velocity distribution in the jets have not been correct. Experimental research work is presented on the complexity of this problem.

RANS computations for identification of 1-D cavitation model parameters: application to full load cavitation vortex rope

NASA Astrophysics Data System (ADS)

Alligné, S.; Decaix, J.; Müller, A.; Nicolet, C.; Avellan, F.; Münch, C.

2017-04-01

Due to the massive penetration of alternative renewable energies, hydropower is a key energy conversion technology for stabilizing the electrical power network by using hydraulic machines at off design operating conditions. At full load, the axisymmetric cavitation vortex rope developing in Francis turbines acts as an internal source of energy, leading to an instability commonly referred to as self-excited surge. 1-D models are developed to predict this phenomenon and to define the range of safe operating points for a hydropower plant. These models require a calibration of several parameters. The present work aims at identifying these parameters by using CFD results as objective functions for an optimization process. A 2-D Venturi and 3-D Francis turbine are considered.

Saturating time-delay transformer for overcurrent protection. [Patent application

DOEpatents

Praeg, W.F.

1975-12-18

Electrical loads connected to dc supplies are protected from damage by overcurrent in the case of a load fault by connecting in series with the load a saturating transformer that detects a load fault and limits the fault current to a safe level for a period long enough to correct the fault or else disconnect the power supply.

Saturating time-delay transformer for overcurrent protection

DOEpatents

Praeg, Walter F.

1977-01-01

Electrical loads connected to d-c supplies are protected from damage by overcurrent in the case of a load fault by connecting in series with the load a saturating transformer that detects a load fault and limits the fault current to a safe level for a period long enough to correct the fault or else disconnect the power supply.

Wind pressure testing of tornado safe room components made from wood

Treesearch

Robert Falk; Deepak Shrestha

2016-01-01

To evaluate the ability of a wood tornado safe room to resist wind pressures produced by a tornado, two safe room com-ponents were tested for wind pressure strength. A tornado safe room ceiling panel and door were static-pressure-tested according to ASTM E 330 using a vacuum test system. Re-sults indicate that the panels had load capacities from 2.4 to 3.5 times that...

14 CFR 25.23 - Load distribution limits.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) Ranges of weights and centers of gravity within which the airplane may be safely operated must be established. If a weight and center of gravity combination is allowable only within certain load distribution... and center of gravity combinations must be established. (b) The load distribution limits may not...

14 CFR 25.23 - Load distribution limits.

Code of Federal Regulations, 2013 CFR

2013-01-01

...) Ranges of weights and centers of gravity within which the airplane may be safely operated must be established. If a weight and center of gravity combination is allowable only within certain load distribution... and center of gravity combinations must be established. (b) The load distribution limits may not...

14 CFR 25.23 - Load distribution limits.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) Ranges of weights and centers of gravity within which the airplane may be safely operated must be established. If a weight and center of gravity combination is allowable only within certain load distribution... and center of gravity combinations must be established. (b) The load distribution limits may not...

14 CFR 25.23 - Load distribution limits.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) Ranges of weights and centers of gravity within which the airplane may be safely operated must be established. If a weight and center of gravity combination is allowable only within certain load distribution... and center of gravity combinations must be established. (b) The load distribution limits may not...

14 CFR 25.23 - Load distribution limits.

Code of Federal Regulations, 2014 CFR

2014-01-01

...) Ranges of weights and centers of gravity within which the airplane may be safely operated must be established. If a weight and center of gravity combination is allowable only within certain load distribution... and center of gravity combinations must be established. (b) The load distribution limits may not...

P-52 Balloting of Hull and Mechanical Standards

DTIC Science & Technology

1992-05-01

N) 3. We connot allow standards from ASTM to be an excuse for the Industry to go sole source. Unless the vendor whose design Is being used has...safe working load is 400 lbs. vii Nicholas Jerqovich (MARAD) 2. Para 4.1.3. - Recommend that "or capacity" be deleted. 3. Para 5.1.1.6 - Delete " stapler ...material is used for plate? (d) Det.E - is incorrectly drawn. . . . 17. Figs 1 & 2 - (a) Det. "X" & "B" are reversed. . . (b) See Fig.A..... if stapler

Fail-safe system for activity cooled supersonic and hypersonic aircraft. [using liquid hydrogen fuel

NASA Technical Reports Server (NTRS)

Jones, R. A.; Braswell, D. O.; Richie, C. B.

1975-01-01

A fail-safe-system concept was studied as an alternative to a redundant active cooling system for supersonic and hypersonic aircraft which use the heat sink of liquid-hydrogen fuel for cooling the aircraft structure. This concept consists of an abort maneuver by the aircraft and a passive thermal protection system (TPS) for the aircraft skin. The abort manuever provides a low-heat-load descent from normal cruise speed to a lower speed at which cooling is unnecessary, and the passive TPS allows the aircraft skin to absorb the abort heat load without exceeding critical skin temperature. On the basis of results obtained, it appears that this fail-safe-system concept warrants further consideration, inasmuch as a fail-safe system could possibly replace a redundant active cooling system with no increase in weight and would offer other potential advantages.

29 CFR 1910.22 - General requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... mechanical handling equipment is used, sufficient safe clearances shall be allowed for aisles, at loading.... (d) Floor loading protection. (1) In every building or other structure, or part thereof, used for... roof of a building or other structure a load greater than that for which such floor or roof is approved...

29 CFR 1910.22 - General requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... mechanical handling equipment is used, sufficient safe clearances shall be allowed for aisles, at loading.... (d) Floor loading protection. (1) In every building or other structure, or part thereof, used for... roof of a building or other structure a load greater than that for which such floor or roof is approved...

29 CFR 1910.22 - General requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... mechanical handling equipment is used, sufficient safe clearances shall be allowed for aisles, at loading.... (d) Floor loading protection. (1) In every building or other structure, or part thereof, used for... roof of a building or other structure a load greater than that for which such floor or roof is approved...

29 CFR 1918.81 - Slinging.

Code of Federal Regulations, 2010 CFR

2010-07-01

... unitized loads during hoisting shall be employed to ensure safe lifting of such loads having damaged... the winch or crane operator(s) can clearly see the draft itself or see the signals of a signalman who... or descending lifting gear. (l) The employer shall not permit employees to ride the hook or the load...

14 CFR 23.613 - Material strength properties and design values.

Code of Federal Regulations, 2011 CFR

2011-01-01

...: (1) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component; 99 percent probability... would result in applied loads being safely distributed to other load carrying members; 90 percent...

14 CFR 23.613 - Material strength properties and design values.

Code of Federal Regulations, 2012 CFR

2012-01-01

...: (1) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component; 99 percent probability... would result in applied loads being safely distributed to other load carrying members; 90 percent...

14 CFR 23.613 - Material strength properties and design values.

Code of Federal Regulations, 2013 CFR

2013-01-01

...: (1) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component; 99 percent probability... would result in applied loads being safely distributed to other load carrying members; 90 percent...

14 CFR 25.613 - Material strength properties and material design values.

Code of Federal Regulations, 2011 CFR

2011-01-01

... following probability: (1) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent... elements would result in applied loads being safely distributed to other load carrying members, 90 percent...

14 CFR 27.613 - Material strength properties and design values.

Code of Federal Regulations, 2013 CFR

2013-01-01

...) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent probability with... elements would result in applied loads being safely distributed to other load-carrying members, 90 percent...

14 CFR 23.613 - Material strength properties and design values.

Code of Federal Regulations, 2014 CFR

2014-01-01

...: (1) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component; 99 percent probability... would result in applied loads being safely distributed to other load carrying members; 90 percent...

14 CFR 25.613 - Material strength properties and material design values.

Code of Federal Regulations, 2014 CFR

2014-01-01

... following probability: (1) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent... elements would result in applied loads being safely distributed to other load carrying members, 90 percent...

14 CFR 29.613 - Material strength properties and design values.

Code of Federal Regulations, 2014 CFR

2014-01-01

...) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent probability with... elements would result in applied loads being safely distributed to other load-carrying members, 90 percent...

14 CFR 25.613 - Material strength properties and material design values.

Code of Federal Regulations, 2012 CFR

2012-01-01

... following probability: (1) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent... elements would result in applied loads being safely distributed to other load carrying members, 90 percent...

14 CFR 27.613 - Material strength properties and design values.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent probability with... elements would result in applied loads being safely distributed to other load-carrying members, 90 percent...

14 CFR 25.613 - Material strength properties and material design values.

Code of Federal Regulations, 2010 CFR

2010-01-01

... following probability: (1) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent... elements would result in applied loads being safely distributed to other load carrying members, 90 percent...

14 CFR 29.613 - Material strength properties and design values.

Code of Federal Regulations, 2010 CFR

2010-01-01

...) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent probability with... elements would result in applied loads being safely distributed to other load-carrying members, 90 percent...

14 CFR 27.613 - Material strength properties and design values.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent probability with... elements would result in applied loads being safely distributed to other load-carrying members, 90 percent...

14 CFR 27.613 - Material strength properties and design values.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent probability with... elements would result in applied loads being safely distributed to other load-carrying members, 90 percent...

14 CFR 25.613 - Material strength properties and material design values.

Code of Federal Regulations, 2013 CFR

2013-01-01

... following probability: (1) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent... elements would result in applied loads being safely distributed to other load carrying members, 90 percent...

14 CFR 23.613 - Material strength properties and design values.

Code of Federal Regulations, 2010 CFR

2010-01-01

...: (1) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component; 99 percent probability... would result in applied loads being safely distributed to other load carrying members; 90 percent...

14 CFR 27.613 - Material strength properties and design values.

Code of Federal Regulations, 2014 CFR

2014-01-01

...) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent probability with... elements would result in applied loads being safely distributed to other load-carrying members, 90 percent...

14 CFR 29.613 - Material strength properties and design values.

Code of Federal Regulations, 2011 CFR

2011-01-01

...) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent probability with... elements would result in applied loads being safely distributed to other load-carrying members, 90 percent...

14 CFR 29.613 - Material strength properties and design values.

Code of Federal Regulations, 2013 CFR

2013-01-01

...) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent probability with... elements would result in applied loads being safely distributed to other load-carrying members, 90 percent...

14 CFR 29.613 - Material strength properties and design values.

Code of Federal Regulations, 2012 CFR

2012-01-01

...) Where applied loads are eventually distributed through a single member within an assembly, the failure of which would result in loss of structural integrity of the component, 99 percent probability with... elements would result in applied loads being safely distributed to other load-carrying members, 90 percent...

Safety profile of solid lipid nanoparticles loaded with rosmarinic acid for oral use: in vitro and animal approaches.

PubMed

Madureira, Ana Raquel; Nunes, Sara; Campos, Débora A; Fernandes, João C; Marques, Cláudia; Zuzarte, Monica; Gullón, Beatriz; Rodríguez-Alcalá, Luís M; Calhau, Conceição; Sarmento, Bruno; Gomes, Ana Maria; Pintado, Maria Manuela; Reis, Flávio

2016-01-01

Rosmarinic acid (RA) possesses several protective bioactivities that have attracted increasing interest by nutraceutical/pharmaceutical industries. Considering the reduced bioavailability after oral use, effective (and safe) delivery systems are crucial to protect RA from gastrointestinal degradation. This study aims to characterize the safety profile of solid lipid nanoparticles produced with Witepsol and Carnauba waxes and loaded with RA, using in vitro and in vivo approaches, focused on genotoxicity and cytotoxicity assays, redox status markers, hematological and biochemical profile, liver and kidney function, gut bacterial microbiota, and fecal fatty acids composition. Free RA and sage extract, empty nanoparticles, or nanoparticles loaded with RA or sage extract (0.15 and 1.5 mg/mL) were evaluated for cell (lymphocytes) viability, necrosis and apoptosis, and antioxidant/prooxidant effects upon DNA. Wistar rats were orally treated for 14 days with vehicle (control) and with Witepsol or Carnauba nanoparticles loaded with RA at 1 and 10 mg/kg body weight/d. Blood, urine, feces, and several tissues were collected for analysis. Free and loaded RA, at 0.15 mg/mL, presented a safe profile, while genotoxic potential was found for the higher dose (1.5 mg/mL), mainly by necrosis. Our data suggest that both types of nanoparticles are safe when loaded with moderate concentrations of RA, without in vitro genotoxicity and cytotoxicity and with an in vivo safety profile in rats orally treated, thus opening new avenues for use in nutraceutical applications.

Safety profile of solid lipid nanoparticles loaded with rosmarinic acid for oral use: in vitro and animal approaches

PubMed Central

Madureira, Ana Raquel; Nunes, Sara; Campos, Débora A; Fernandes, João C; Marques, Cláudia; Zuzarte, Monica; Gullón, Beatriz; Rodríguez-Alcalá, Luís M; Calhau, Conceição; Sarmento, Bruno; Gomes, Ana Maria; Pintado, Maria Manuela; Reis, Flávio

2016-01-01

Rosmarinic acid (RA) possesses several protective bioactivities that have attracted increasing interest by nutraceutical/pharmaceutical industries. Considering the reduced bioavailability after oral use, effective (and safe) delivery systems are crucial to protect RA from gastrointestinal degradation. This study aims to characterize the safety profile of solid lipid nanoparticles produced with Witepsol and Carnauba waxes and loaded with RA, using in vitro and in vivo approaches, focused on genotoxicity and cytotoxicity assays, redox status markers, hematological and biochemical profile, liver and kidney function, gut bacterial microbiota, and fecal fatty acids composition. Free RA and sage extract, empty nanoparticles, or nanoparticles loaded with RA or sage extract (0.15 and 1.5 mg/mL) were evaluated for cell (lymphocytes) viability, necrosis and apoptosis, and antioxidant/prooxidant effects upon DNA. Wistar rats were orally treated for 14 days with vehicle (control) and with Witepsol or Carnauba nanoparticles loaded with RA at 1 and 10 mg/kg body weight/d. Blood, urine, feces, and several tissues were collected for analysis. Free and loaded RA, at 0.15 mg/mL, presented a safe profile, while genotoxic potential was found for the higher dose (1.5 mg/mL), mainly by necrosis. Our data suggest that both types of nanoparticles are safe when loaded with moderate concentrations of RA, without in vitro genotoxicity and cytotoxicity and with an in vivo safety profile in rats orally treated, thus opening new avenues for use in nutraceutical applications. PMID:27536103

Aging Theories for Establishing Safe Life Spans of Airborne Critical Structural Components

NASA Technical Reports Server (NTRS)

Ko, William L.

2003-01-01

New aging theories have been developed to establish the safe life span of airborne critical structural components such as B-52B aircraft pylon hooks for carrying air-launch drop-test vehicles. The new aging theories use the equivalent-constant-amplitude loading spectrum to represent the actual random loading spectrum with the same damaging effect. The crack growth due to random loading cycling of the first flight is calculated using the half-cycle theory, and then extrapolated to all the crack growths of the subsequent flights. The predictions of the new aging theories (finite difference aging theory and closed-form aging theory) are compared with the classical flight-test life theory and the previously developed Ko first- and Ko second-order aging theories. The new aging theories predict the number of safe flights as considerably lower than that predicted by the classical aging theory, and slightly lower than those predicted by the Ko first- and Ko second-order aging theories due to the inclusion of all the higher order terms.

Structural Health Management of Damaged Aircraft Structures Using the Digital Twin Concept

NASA Technical Reports Server (NTRS)

Seshadri, Banavara R.; Krishnamurthy, Thiagarajan

2017-01-01

The development of multidisciplinary integrated Structural Health Management (SHM) tools will enable accurate detection, and prognosis of damaged aircraft under normal and adverse conditions during flight. As part of the digital twin concept, methodologies are developed by using integrated multiphysics models, sensor information and input data from an in-service vehicle to mirror and predict the life of its corresponding physical twin. SHM tools are necessary for both damage diagnostics and prognostics for continued safe operation of damaged aircraft structures. The adverse conditions include loss of control caused by environmental factors, actuator and sensor faults or failures, and structural damage conditions. A major concern in these structures is the growth of undetected damage/cracks due to fatigue and low velocity foreign object impact that can reach a critical size during flight, resulting in loss of control of the aircraft. To avoid unstable, catastrophic propagation of damage during a flight, load levels must be maintained that are below a reduced load-carrying capacity for continued safe operation of an aircraft. Hence, a capability is needed for accurate real-time predictions of damage size and safe load carrying capacity for structures with complex damage configurations. In the present work, a procedure is developed that uses guided wave responses to interrogate damage. As the guided wave interacts with damage, the signal attenuates in some directions and reflects in others. This results in a difference in signal magnitude as well as phase shifts between signal responses for damaged and undamaged structures. Accurate estimation of damage size, location, and orientation is made by evaluating the cumulative signal responses at various pre-selected sensor locations using a genetic algorithm (GA) based optimization procedure. The damage size, location, and orientation is obtained by minimizing the difference between the reference responses and the responses obtained by wave propagation finite element analysis of different representative cracks, geometries, and sizes.

The complex interaction between anxiety and cognition: insight from spatial and verbal working memory

PubMed Central

Vytal, Katherine E.; Cornwell, Brian R.; Letkiewicz, Allison M.; Arkin, Nicole E.; Grillon, Christian

2013-01-01

Anxiety can be distracting, disruptive, and incapacitating. Despite problems with empirical replication of this phenomenon, one fruitful avenue of study has emerged from working memory (WM) experiments where a translational method of anxiety induction (risk of shock) has been shown to disrupt spatial and verbal WM performance. Performance declines when resources (e.g., spatial attention, executive function) devoted to goal-directed behaviors are consumed by anxiety. Importantly, it has been shown that anxiety-related impairments in verbal WM depend on task difficulty, suggesting that cognitive load may be an important consideration in the interaction between anxiety and cognition. Here we use both spatial and verbal WM paradigms to probe the effect of cognitive load on anxiety-induced WM impairment across task modality. Subjects performed a series of spatial and verbal n-back tasks of increasing difficulty (1, 2, and 3-back) while they were safe or at risk for shock. Startle reflex was used to probe anxiety. Results demonstrate that induced-anxiety differentially impacts verbal and spatial WM, such that low and medium-load verbal WM is more susceptible to anxiety-related disruption relative to high-load, and spatial WM is disrupted regardless of task difficulty. Anxiety impacts both verbal and spatial processes, as described by correlations between anxiety and performance impairment, albeit the effect on spatial WM is consistent across load. Demanding WM tasks may exert top-down control over higher-order cortical resources engaged by anxious apprehension, however high-load spatial WM may continue to experience additional competition from anxiety-related changes in spatial attention, resulting in impaired performance. By describing this disruption across task modalities, these findings inform current theories of emotion–cognition interactions and may facilitate development of clinical interventions that seek to target cognitive impairments associated with anxiety. PMID:23542914

Development of implants composed of bioactive materials for bone repair

NASA Astrophysics Data System (ADS)

Xiao, Wei

The purpose of this Ph.D. research was to address the clinical need for synthetic bioactive materials to heal defects in non-loaded and loaded bone. Hollow hydroxyapatite (HA) microspheres created in a previous study were evaluated as a carrier for controlled release of bone morphogenetic protein-2 (BMP2) in bone regeneration. New bone formation in rat calvarial defects implanted with BMP2-loaded microspheres (43%) was significantly higher than microspheres without BMP2 (17%) at 6 weeks postimplantation. Then hollow HA microspheres with a carbonate-substituted composition were prepared to improve their resorption rate. Hollow HA microspheres with 12 wt. % of carbonate showed significantly higher new bone formation (73 +/- 8%) and lower residual HA (7 +/- 2%) than stoichiometric HA microspheres (59 +/- 2% new bone formation; 21 +/- 3% residual HA). The combination of carbonate-substituted hollow HA microspheres and clinically-safe doses of BMP2 could provide promising implants for healing non-loaded bone defects. Strong porous scaffolds of bioactive silicate (13-93) glass were designed with the aid of finite-element modeling, created by robocasting and evaluated for loaded bone repair. Scaffolds with a porosity gradient to mimic human cortical bone showed a compressive strength of 88 +/- 20 MPa, a flexural strength of 34 +/- 5 MPa and the ability to support bone infiltration in vivo. The addition of a biodegradable polylactic acid (PLA) layer to the external surface of these scaffolds increased their load-bearing capacity in four-point bending by 50% and dramatically enhanced their work of fracture, resulting in a "ductile" mechanical response. These bioactive glass-PLA composites, combining bioactivity, high strength, high work of fracture and an internal architecture conducive to bone infiltration, could provide optimal implants for structural bone repair.

29 CFR 1917.111 - Maintenance and load limits.

Code of Federal Regulations, 2010 CFR

2010-07-01

... maintained. (b) Maximum safe load limits, in pounds per square foot (kilograms per square meter), of floors elevated above ground level, and pier structures over the water shall be conspicuously posted in all cargo...

Study on Fatigue Performance of Composite Bolted Joints with Bolt-Hole Delamination

NASA Astrophysics Data System (ADS)

Liu, M. J.; Yu, S.; Zhao, Q. Y.

2018-03-01

Fatigue performance of composite structure with imperfections is a challenging subject at present. Based on cohesive zone method and multi-continuum theory, delamination evolution response and fatigue life prediction of a 3D composite single-lap joint with a bolt-hole have been investigated through computer codes Abaqus and Fe-safe. Results from the comparison of a perfect composite bolted joint with another defect one indicates that a relatively small delamination damage around the bolt hole brings about significant degradation of local material performance. More notably, fatigue life of stress concentration region of composite bolted joints is highly sensitive to external loads, as an increase of 67% cyclic load amplitude leads to an decrease of 99.5% local fatigue life in this study. However, the numerical strategy for solving composite fatigue problems is meaningful to engineering works.

49 CFR 393.87 - Warning flags on projecting loads.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 5 2012-10-01 2012-10-01 false Warning flags on projecting loads. 393.87 Section... ACCESSORIES NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.87 Warning flags on... load marked with red or orange fluorescent warning flags. Each warning flag must be at least 457 mm (18...

49 CFR 393.87 - Warning flags on projecting loads.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 5 2011-10-01 2011-10-01 false Warning flags on projecting loads. 393.87 Section... ACCESSORIES NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.87 Warning flags on... load marked with red or orange fluorescent warning flags. Each warning flag must be at least 457 mm (18...

49 CFR 393.87 - Warning flags on projecting loads.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 5 2013-10-01 2013-10-01 false Warning flags on projecting loads. 393.87 Section... ACCESSORIES NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.87 Warning flags on... load marked with red or orange fluorescent warning flags. Each warning flag must be at least 457 mm (18...

49 CFR 393.87 - Warning flags on projecting loads.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 5 2010-10-01 2010-10-01 false Warning flags on projecting loads. 393.87 Section... ACCESSORIES NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.87 Warning flags on... load marked with red or orange fluorescent warning flags. Each warning flag must be at least 457 mm (18...

49 CFR 393.87 - Warning flags on projecting loads.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 5 2014-10-01 2014-10-01 false Warning flags on projecting loads. 393.87 Section... ACCESSORIES NECESSARY FOR SAFE OPERATION Miscellaneous Parts and Accessories § 393.87 Warning flags on... load marked with red or orange fluorescent warning flags. Each warning flag must be at least 457 mm (18...

29 CFR 1926.905 - Loading of explosives or blasting agents.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 8 2010-07-01 2010-07-01 false Loading of explosives or blasting agents. 1926.905 Section... Explosives § 1926.905 Loading of explosives or blasting agents. (a) Procedures that permit safe and efficient... have contained explosives or blasting agents. (g) No explosives or blasting agents shall be left...

Rapid Propellant Loading Approach Exploration

DTIC Science & Technology

2010-11-01

the impact upon ground operations of three configuration options. Ground operations management was addressed through a series of studies performed...and operations management system can enable safe rapid propellant loading operations with limited operator knowledge and involvement. A single

Some Remarks on Foundation Pile Testing Procedures

NASA Astrophysics Data System (ADS)

Rybak, Jarosław

2017-10-01

This work presents the review of pile capacity testing techniques. In an overview, the key points in pile designing are: determination of the appropriate computational schemes, reliable data on loads and the properties of structural materials (in particular, of the soil mass, which is marked by the greatest variability). The procedure of constructing a pile foundation should include: carrying out soil tests in the scope that ensures safe designing, selecting a piling technology that is relevant both to geotechnical conditions and expected loads, drafting a piling design together with the design of load tests, setting up a testing station for further load tests, static and/or dynamic tests of pile load capacity, preceded by supplementary soil tests when the conditions of test pile installation fail to comply with the design assumptions or when the pile length exceeds the depth of the previously investigated soil, making documentation of load capacity tests (with an additional correction of the piling design), the actual piling (ongoing analysis of pile driving logs and, if necessary, testing the piles’ integrity), drawing up the as-built documentation. Unfortunately, the design is corrected after the load test have been conducted only if the piles fail to show the designed bearing capacity. The designer is then obliged to revise the design assumptions on the basis of tests results. If the test results account for the a greater bearing capacity than necessary and it would be recommendable to limit the extent of the planned (i.e. set out in the contract) piling works, usually neither the contractor nor the designer, nor even the Construction Site Supervisor, acting for the benefit of the Investor, are willing to take on the responsibility for reducing the scope of the piling works. The necessity of conducting additional control tests before and during the implementation of the construction project is often treated by the investors as an attempt at extorting extra financial resources or at delaying the project implementation. The designer, however, has no other possibility (and often - he/she does not have required qualifications) to verify the obtained test results.

Exercise Equipment: Neutral Buoyancy

NASA Technical Reports Server (NTRS)

Shackelford, Linda; Valle, Paul

2016-01-01

Load Bearing Equipment for Neutral Buoyancy (LBE-NB) is an exercise frame that holds two exercising subjects in position as they apply counter forces to each other for lower extremity and spine loading resistance exercises. Resistance exercise prevents bone loss on ISS, but the ISS equipment is too massive for use in exploration craft. Integrating the human into the load directing, load generating, and motion control functions of the exercise equipment generates safe exercise loads with less equipment mass and volume.

Numerical verification of two-component dental implant in the context of fatigue life for various load cases.

PubMed

Szajek, Krzysztof; Wierszycki, Marcin

2016-01-01

Dental implant designing is a complex process which considers many limitations both biological and mechanical in nature. In earlier studies, a complete procedure for improvement of two-component dental implant was proposed. However, the optimization tasks carried out required assumption on representative load case, which raised doubts on optimality for the other load cases. This paper deals with verification of the optimal design in context of fatigue life and its main goal is to answer the question if the assumed load scenario (solely horizontal occlusal load) leads to the design which is also "safe" for oblique occlussal loads regardless the angle from an implant axis. The verification is carried out with series of finite element analyses for wide spectrum of physiologically justified loads. The design of experiment methodology with full factorial technique is utilized. All computations are done in Abaqus suite. The maximal Mises stress and normalized effective stress amplitude for various load cases are discussed and compared with the assumed "safe" limit (equivalent of fatigue life for 5e6 cycles). The obtained results proof that coronial-appical load component should be taken into consideration in the two component dental implant when fatigue life is optimized. However, its influence in the analyzed case is small and does not change the fact that the fatigue life improvement is observed for all components within whole range of analyzed loads.

A multifunctional PVDF-based tactile sensor for minimally invasive surgery

NASA Astrophysics Data System (ADS)

Sokhanvar, S.; Packirisamy, M.; Dargahi, J.

2007-08-01

In this paper a multifunctional tactile sensor system using PVDF (polyvinylidene fluoride), is proposed, designed, analyzed, tested and validated. The working principle of the sensor is in such a way that it can be used in combination with almost any end-effectors. However, the sensor is particularly designed to be integrated with minimally invasive surgery (MIS) tools. In addition, the structural and transduction materials are selected to be compatible with micro-electro-mechanical systems (MEMS) technology, so that miniaturization would be possible. The corrugated shape of the sensor ensures the safe tissue grasping and compatibility with the traditional tooth-like end effectors of MIS tools. A unit of this sensor comprised of a base, a flexible beam and three PVDF sensing elements. Two PVDF sensing elements sandwiched at the end supports work in thickness mode to measure the magnitude and position of applied load. The third PVDF sensing element is attached to the beam and it works in the extensional mode to measure the softness of the contact object. The proposed sensor is modeled both analytically and numerically and a series of simulations are performed in order to estimate the characteristics of the sensor in measuring the magnitude and position of a point load, distributed load, and also the softness of the contact object. Furthermore, in order to validate the theoretical results, the prototyped sensor was tested and the results are compared. The results are very promising and proving the capability of the sensor for haptic sensing.

Pulse mitigation and heat transfer enhancement techniques. Volume 3: Liquid sodium heat transfer facility and transient response of sodium heat pipe to pulse forward and reverse heat load

NASA Astrophysics Data System (ADS)

Chow, L. C.; Hahn, O. J.; Nguyen, H. X.

1992-08-01

This report presents the description of a liquid sodium heat transfer facility (sodium loop) constructed to support the study of transient response of heat pipes. The facility, consisting of the loop itself, a safety system, and a data acquisition system, can be safely operated over a wide range of temperature and sodium flow rate. The transient response of a heat pipe to pulse heat load at the condenser section was experimentally investigated. A 0.457 m screen wick, sodium heat pipe with an outer diameter of 0.127 m was tested under different heat loading conditions. A major finding was that the heat pipe reversed under a pulse heat load applied at the condenser. The time of reversal was approximately 15 to 25 seconds. The startup of the heat pipe from frozen state was also studied. It was found that during the startup process, at least part of the heat pipe was active. The active region extended gradually down to the end of the condenser until all of the working fluid in the heat pipe was molten.

Simulation of systems for shock wave/compression waves damping in technological plants

NASA Astrophysics Data System (ADS)

Sumskoi, S. I.; Sverchkov, A. M.; Lisanov, M. V.; Egorov, A. F.

2016-09-01

At work of pipeline systems, flow velocity decrease can take place in the pipeline as a result of the pumps stop, the valves shutdown. As a result, compression waves appear in the pipeline systems. These waves can propagate in the pipeline system, leading to its destruction. This phenomenon is called water hammer (water hammer flow). The most dangerous situations occur when the flow is stopped quickly. Such urgent flow cutoff often takes place in an emergency situation when liquid hydrocarbons are being loaded into sea tankers. To prevent environment pollution it is necessary to stop the hydrocarbon loading urgently. The flow in this case is cut off within few seconds. To prevent an increase in pressure in a pipeline system during water hammer flow, special protective systems (pressure relief systems) are installed. The approaches to systems of protection against water hammer (pressure relief systems) modeling are described in this paper. A model of certain pressure relief system is considered. It is shown that in case of an increase in the intensity of hydrocarbons loading at a sea tanker, presence of the pressure relief system allows to organize safe mode of loading.

Biocompatible and colloidally stabilized mPEG-PE/calcium phosphate hybrid nanoparticles loaded with siRNAs targeting tumors

PubMed Central

Gao, Pei; Zhang, Xiangyu; Wang, Hongzhi; Zhang, Qinghong

2016-01-01

Calcium phosphate nanoparticles are safe and effective delivery vehicles for small interfering RNA (siRNA), as a result of their excellent biocompatibility. In this work, mPEG-PE (polyethylene glycol-L-α-phosphatidylethanolamine) was synthesized and used to prepare nanoparticles composed of mPEG-PE and calcium phosphate for siRNA delivery. Calcium phosphate and mPEG-PE formed the stable hybrid nanoparticles through self-assembly resulting from electrostatic interaction in water. The average size of the hybrid nanoparticles was approximately 53.2 nm with a negative charge of approximately −16.7 mV, which was confirmed by dynamic light scattering (DLS) measurements. The nanoparticles exhibited excellent stability in serum and could protect siRNA from ribonuclease (RNase) degradation. The cellular internalization of siRNA-loaded nanoparticles was evaluated in SMMC-7721 cells using a laser scanning confocal microscope (CLSM) and flow cytometry. The hybrid nanoparticles could efficiently deliver siRNA to cells compared with free siRNA. Moreover, the in vivo distribution of Cy5-siRNA-loaded hybrid nanoparticles was observed after being injected into tumor-bearing nude mice. The nanoparticles concentrated in the tumor regions through an enhanced permeability and retention (EPR) effect based on the fluorescence intensities of tissue distribution. A safety evaluation of the nanoparticles was performed both in vitro and in vivo demonstrating that the hybrid nanoparticle delivery system had almost no toxicity. These results indicated that the mPEG-PE/CaP hybrid nanoparticles could be a stable, safe and promising siRNA nanocarrier for anticancer therapy. PMID:26625203

Biocompatible and colloidally stabilized mPEG-PE/calcium phosphate hybrid nanoparticles loaded with siRNAs targeting tumors.

PubMed

Gao, Pei; Zhang, Xiangyu; Wang, Hongzhi; Zhang, Qinghong; Li, He; Li, Yaogang; Duan, Yourong

2016-01-19

Calcium phosphate nanoparticles are safe and effective delivery vehicles for small interfering RNA (siRNA), as a result of their excellent biocompatibility. In this work, mPEG-PE (polyethylene glycol-L-α-phosphatidylethanolamine) was synthesized and used to prepare nanoparticles composed of mPEG-PE and calcium phosphate for siRNA delivery. Calcium phosphate and mPEG-PE formed the stable hybrid nanoparticles through self-assembly resulting from electrostatic interaction in water. The average size of the hybrid nanoparticles was approximately 53.2 nm with a negative charge of approximately -16.7 mV, which was confirmed by dynamic light scattering (DLS) measurements. The nanoparticles exhibited excellent stability in serum and could protect siRNA from ribonuclease (RNase) degradation. The cellular internalization of siRNA-loaded nanoparticles was evaluated in SMMC-7721 cells using a laser scanning confocal microscope (CLSM) and flow cytometry. The hybrid nanoparticles could efficiently deliver siRNA to cells compared with free siRNA. Moreover, the in vivo distribution of Cy5-siRNA-loaded hybrid nanoparticles was observed after being injected into tumor-bearing nude mice. The nanoparticles concentrated in the tumor regions through an enhanced permeability and retention (EPR) effect based on the fluorescence intensities of tissue distribution. A safety evaluation of the nanoparticles was performed both in vitro and in vivo demonstrating that the hybrid nanoparticle delivery system had almost no toxicity. These results indicated that the mPEG-PE/CaP hybrid nanoparticles could be a stable, safe and promising siRNA nanocarrier for anticancer therapy.

Design criteria for portable timber bridge systems : static versus dynamic loads

Treesearch

John M. Franklin; S. E. Taylor; Paul A. Morgan; M. A. Ritter

1999-01-01

Design criteria are needed specifically for portable bridges to insure that they are safe and cost effective. This paper discusses different portable bridge categories and their general design criteria. Specific emphasis is given to quantifying the effects of dynamic live loads on portable bridge design. Results from static and dynamic load tests of two portable timber...

Development of a homogeneous pulse shape discriminating flow-cell radiation detection system

NASA Astrophysics Data System (ADS)

Hastie, K. H.; DeVol, T. A.; Fjeld, R. A.

1999-02-01

A homogeneous flow-cell radiation detection system which utilizes coincidence counting and pulse shape discrimination circuitry was assembled and tested with five commercially available liquid scintillation cocktails. Two of the cocktails, Ultima Flo (Packard) and Mono Flow 5 (National Diagnostics) have low viscosities and are intended for flow applications; and three of the cocktails, Optiphase HiSafe 3 (Wallac), Ultima Gold AB (Packard), and Ready Safe (Beckman), have higher viscosities and are intended for static applications. The low viscosity cocktails were modified with 1-methylnaphthalene to increase their capability for alpha/beta pulse shape discrimination. The sample loading and pulse shape discriminator setting were optimized to give the lowest minimum detectable concentration for alpha radiation in a 30 s count time. Of the higher viscosity cocktails, Optiphase HiSafe 3 had the lowest minimum detectable activities for alpha and beta radiation, 0.2 and 0.4 Bq/ml for 233U and 90Sr/ 90Y, respectively, for a 30 s count time. The sample loading was 70% and the corresponding alpha/beta spillover was 5.5%. Of the low viscosity cocktails, Mono Flow 5 modified with 2.5% (by volume) 1-methylnaphthalene resulted in the lowest minimum detectable activities for alpha and beta radiation; 0.3 and 0.5 Bq/ml for 233U and 90Sr/ 90Y, respectively, for a 30 s count time. The sample loading was 50%, and the corresponding alpha/beta spillover was 16.6%. HiSafe 3 at a 10% sample loading was used to evaluate the system under simulated flow conditions.

[Special beds. Pulmonary therapy system].

PubMed

Calixto Rodríguez, Joaquín; Rodríguez Martínez, Xavier; Marín i Vivó, Gemma; Paunellas Albert, Josep

2008-10-01

To be bedridden reduces one's capacity to move and produces muscular debility that affects the respiratory system leading to a decreased effectiveness in expectoration, the ability to spit up sputum. The pulmonary therapy system integrated in a bed is the result of applying motorized elements to the articulation points of the bad in order to achieve safe positions at therapeutic angles, which improve the breathing-perfusion (blood flow) relationship. This system also makes it possible to apply vibration waves to the patient which favor the elimination of bronchial-pulmonary secretions, the rehabilitation of the bedridden patient and decrease the work load for nursing personnel.

Transport and installation of the Dark Energy Survey CCD imager

NASA Astrophysics Data System (ADS)

Derylo, Greg; Chi, Edward; Diehl, H. Thomas; Estrada, Juan; Flaugher, Brenna; Schultz, Ken

2012-09-01

The Dark Energy Survey CCD imager was constructed at the Fermi National Accelerator Laboratory and delivered to the Cerro Tololo Inter-American Observatory in Chile for installation onto the Blanco 4m telescope. Several efforts are described relating to preparation of the instrument for transport, development and testing of a shipping crate designed to minimize transportation loads transmitted to the camera, and inspection of the imager upon arrival at the observatory. Transportation loads were monitored and are described. For installation of the imager at the telescope prime focus, where it mates with its previously-installed optical corrector, specialized tooling was developed to safely lift, support, and position the vessel. The installation and removal processes were tested on the Telescope Simulator mockup at FNAL, thus minimizing technical and schedule risk for the work performed at CTIO. Final installation of the imager is scheduled for August 2012.

DEMONSTRATION OF VAPOR CONTROL TECHNOLOGY FOR GASOLINE LOADING OF BARGES

EPA Science Inventory

The report gives results of a program to demonstrate a safe cost-effective way to control gasoline vapors emitted during barge loading. Refrigeration, carbon adsorption, oil absorption, and incineration were reviewed in terms of their safety, economics, and performance. Two barge...

Modified hydraulic braking system limits angular deceleration to safe values

NASA Technical Reports Server (NTRS)

Briggs, R. S.; Council, M.; Green, P. M.

1966-01-01

Conventional spring actuated, hydraulically released, fail-safe disk braking system is modified to control the angular deceleration of a massive antenna. The hydraulic system provides an immediate preset pressure to the spring-loaded brake shoes and holds it at this value to decelerate the antenna at the desired rate.

Mechanical analysis of infant carrying in hominoids

PubMed Central

2007-01-01

In all higher nonhuman primates, species survival depends upon safe carrying of infants clinging to body hair of adults. In this work, measurements of mechanical properties of ape hair (gibbon, orangutan, and gorilla) are presented, focusing on constraints for safe infant carrying. Results of hair tensile properties are shown to be species-dependent. Analysis of the mechanics of the mounting position, typical of heavier infant carrying among African apes, shows that both clinging and friction are necessary to carry heavy infants. As a consequence, a required relationship between infant weight, hair–hair friction coefficient, and body angle exists. The hair–hair friction coefficient is measured using natural ape skin samples, and dependence on load and humidity is analyzed. Numerical evaluation of the equilibrium constraint is in agreement with the knuckle-walking quadruped position of African apes. Bipedality is clearly incompatible with the usual clinging and mounting pattern of infant carrying, requiring a revision of models of hominization in relation to the divergence between apes and hominins. These results suggest that safe carrying of heavy infants justify the emergence of biped form of locomotion. Ways to test this possibility are foreseen here. PMID:18030438

Staying Healthy and Safe at Work

MedlinePlus

... The Prematurity Campaign About us Annual report Our work Community impact Global programs Research Need help? Frequently ... safe at work Staying healthy and safe at work E-mail to a friend Please fill in ...

46th Annual Gun and Missile Systems Conference and Exhibition. Volume 3 - Thursday

DTIC Science & Technology

2011-09-01

Grade Sensors Through Use of Accelerated Aging Principles Mr. Scott Gift 11657 Modeling of the Autofrettage Processes of a Gun Barrel Mr. Sudhir...Emissions Measured on the Outer Portion of a Composite Barrel Ms. Rushie Ghimire GUN & MISSILE SYSTEMS ADDITIONAL AUTHORS GUN & MISSILE SYSTEMS...Transportation – Loading – Gun Fire to Barrel Exit – After Barrel Exit • Passing: Fuze safety devices remain safe; safe for disposal or safe for

[Emerging problems in enforcement of safe maternity and feeding protection at work: a public prevention service experience].

PubMed

Tarchi, M; Bartoli, D; Demi, A; Dini, F; Farina, G A; Sannino, G

2007-01-01

We have examined the claims for advance maternity leave or prolonged benefits for breastfeeding addressed to Occupational Health Unity of Local Health Service 11 by women at harmful works in the period 2002-2005. The most frequent occupations were: shoemaker (29%), service company's employee (7%), tanners (7%), leather industry's employee (6%) and food industry's employee (6%). The most important risk factors were: bound postures, manual load handling, chemical hazards and biological agents. The numbers of claims increased during the period of interest. In the work place often risks for pregnancy and breastfeeding are not correctly assessed and women workers are not informed on their rights. The Occupational Health Unity of Local Health Service 11 tried to correct the lack of information for workers, employers, workers' representatives in health and safety and enterprise's occupational health physician.

Ergonomics analyses of five joineries located in Florianópolis-SC, using the LEST Method.

PubMed

Vergara, Lizandra Lupi Garcia; Garcia, Carolina Schwinden; Miranda, Felipe Vergara

2012-01-01

Considering the goal of Ergonomic Work Analysis to establish, from the point of view of workers, safe, healthy, comfortable and efficient environments, this study propose to analyze the work situation of machine operators at five joineries from Florianópolis-SC. For this, it was applied the LEST Method to evaluate the task made by the operators, considering the physical, cognitive and organizational work environment. As results, it was identified the main ergonomics problems of these workstations, presenting an ergonomic diagnosis and their implications on health and safety of workers. As result, it was concluded that the main ergonomics problems at joineries are related with noise, with constant load of weight and with the postures taken. Besides these problems, others were diagnosed, for example, the pressure for workers to comply strictly the task stipulated and also the poor training and capacity of workers.

Doxorubicin-Loaded Nanobubbles Combined with Extracorporeal Shock Waves: Basis for a New Drug Delivery Tool in Anaplastic Thyroid Cancer.

PubMed

Marano, Francesca; Argenziano, Monica; Frairia, Roberto; Adamini, Aloe; Bosco, Ornella; Rinella, Letizia; Fortunati, Nicoletta; Cavalli, Roberta; Catalano, Maria Graziella

2016-05-01

No standard chemotherapy is available for anaplastic thyroid cancer (ATC). Drug-loaded nanobubbles (NBs) are a promising innovative anticancer drug formulation, and combining them with an externally applied trigger may further control drug release at the target region. Extracorporeal shock waves (ESWs) are acoustic waves widely used in urology and orthopedics, with no side effects. The aim of the present work was to combine ESWs and new doxorubicin-loaded glycol chitosan NBs in order to target doxorubicin and enhance its antitumor effect in ATC cell lines. CAL-62 and 8305C cells were treated with empty NBs, fluorescent NBs, free doxorubicin, and doxorubicin-loaded NBs in the presence or in the absence of ESWs. NB entrance was evaluated by fluorescence microscopy and flow cytofluorimetry. Cell viability was assessed by Trypan Blue exclusion and WST-1 proliferation assays. Doxorubicin intracellular content was measured by high-performance liquid chromatography. Treatment with empty NBs and ESWs, even in combination, was safe, as cell viability and growth were not affected. Loading NBs with doxorubicin and combining them with ESWs generated the highest cytotoxic effect, resulting in drug GI50 reduction of about 40%. Mechanistically, ESWs triggered intracellular drug release from NBs, resulting in the highest nuclear drug content. Combined treatment with doxorubicin-loaded NBs and ESWs is a promising drug delivery tool for ATC treatment with the possibility of using lower doxorubicin doses and thus limiting its systemic side effects.

14 CFR 23.305 - Strength and deformation.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Strength and deformation. 23.305 Section 23.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT..., permanent deformation. At any load up to limit loads, the deformation may not interfere with safe operation...

14 CFR 23.305 - Strength and deformation.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Strength and deformation. 23.305 Section 23.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT..., permanent deformation. At any load up to limit loads, the deformation may not interfere with safe operation...

14 CFR 27.305 - Strength and deformation.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Strength and deformation. 27.305 Section 27.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... deformation. At any load up to limit loads, the deformation may not interfere with safe operation. (b) The...

14 CFR 27.305 - Strength and deformation.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Strength and deformation. 27.305 Section 27.305 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT... deformation. At any load up to limit loads, the deformation may not interfere with safe operation. (b) The...

14 CFR 23.23 - Load distribution limits.

Code of Federal Regulations, 2012 CFR

2012-01-01

... distribution limits. (a) Ranges of weights and centers of gravity within which the airplane may be safely operated must be established. If a weight and center of gravity combination is allowable only within... established for the corresponding weight and center of gravity combinations. (b) The load distribution limits...

14 CFR 23.23 - Load distribution limits.

Code of Federal Regulations, 2013 CFR

2013-01-01

... distribution limits. (a) Ranges of weights and centers of gravity within which the airplane may be safely operated must be established. If a weight and center of gravity combination is allowable only within... established for the corresponding weight and center of gravity combinations. (b) The load distribution limits...

14 CFR 23.23 - Load distribution limits.

Code of Federal Regulations, 2014 CFR

2014-01-01

... distribution limits. (a) Ranges of weights and centers of gravity within which the airplane may be safely operated must be established. If a weight and center of gravity combination is allowable only within... established for the corresponding weight and center of gravity combinations. (b) The load distribution limits...

14 CFR 23.23 - Load distribution limits.

Code of Federal Regulations, 2010 CFR

2010-01-01

... distribution limits. (a) Ranges of weights and centers of gravity within which the airplane may be safely operated must be established. If a weight and center of gravity combination is allowable only within... established for the corresponding weight and center of gravity combinations. (b) The load distribution limits...

14 CFR 23.23 - Load distribution limits.

Code of Federal Regulations, 2011 CFR

2011-01-01

... distribution limits. (a) Ranges of weights and centers of gravity within which the airplane may be safely operated must be established. If a weight and center of gravity combination is allowable only within... established for the corresponding weight and center of gravity combinations. (b) The load distribution limits...

Fracture control methods for space vehicles. Volume 1: Fracture control design methods. [for space shuttle configuration planning

NASA Technical Reports Server (NTRS)

Liu, A. F.

1974-01-01

A systematic approach for applying methods for fracture control in the structural components of space vehicles consists of four major steps. The first step is to define the primary load-carrying structural elements and the type of load, environment, and design stress levels acting upon them. The second step is to identify the potential fracture-critical parts by means of a selection logic flow diagram. The third step is to evaluate the safe-life and fail-safe capabilities of the specified part. The last step in the sequence is to apply the control procedures that will prevent damage to the fracture-critical parts. The fracture control methods discussed include fatigue design and analysis methods, methods for preventing crack-like defects, fracture mechanics analysis methods, and nondestructive evaluation methods. An example problem is presented for evaluation of the safe-crack-growth capability of the space shuttle crew compartment skin structure.

Braking System for Wind Turbines

NASA Technical Reports Server (NTRS)

Krysiak, J. E.; Webb, F. E.

1987-01-01

Operating turbine stopped smoothly by fail-safe mechanism. Windturbine braking systems improved by system consisting of two large steel-alloy disks mounted on high-speed shaft of gear box, and brakepad assembly mounted on bracket fastened to top of gear box. Lever arms (with brake pads) actuated by spring-powered, pneumatic cylinders connected to these arms. Springs give specific spring-loading constant and exert predetermined load onto brake pads through lever arms. Pneumatic cylinders actuated positively to compress springs and disengage brake pads from disks. During power failure, brakes automatically lock onto disks, producing highly reliable, fail-safe stops. System doubles as stopping brake and "parking" brake.

Organic matter degradation in a greywater recycling system using a multistage moving bed biofilm reactor (MBBR).

PubMed

Saidi, Assia; Masmoudi, Khaoula; Nolde, Erwin; El Amrani, Btissam; Amraoui, Fouad

2017-12-01

Greywater is an important non-conventional water resource which can be treated and recycled in buildings. A decentralized greywater recycling system for 223 inhabitants started operating in 2006 in Berlin, Germany. High load greywater undergoes advanced treatment in a multistage moving bed biofilm reactor (MBBR) followed by sand filtration and UV disinfection. The treated water is used safely as service water for toilet flushing. Monitoring of the organic matter degradation was pursued to describe the degradation processes in each stage and optimize the system. Results showed that organic matter reduction was achieved for the most part in the first three reactors, whereas the highest reduction rate was observed in the third reactor in terms of COD (chemical oxygen demand), dissolved organic carbon and BOD 7 (biological oxygen demand). The results also showed that the average loading rate entering the system was 3.7 kg COD/d, while the removal rate was 3.4 kg COD/d in a total bioreactor volume of 11.7 m³. In terms of BOD, the loading rate was 2.8 kg BOD/d and it was almost totally removed. This system requires little space (0.15 m²/person) and maintenance work of less than one hour per month and it shows operational stability under peak loads.

Study of fail-safe abort system for an actively cooled hypersonic aircraft, volume 2

NASA Technical Reports Server (NTRS)

Peeples, M. E.; Herring, R. L.

1976-01-01

Conceptual designs of a fail-safe abort system for hydrogen fueled actively cooled high speed aircraft are examined. The fail-safe concept depends on basically three factors: (1) a reliable method of detecting a failure or malfunction in the active cooling system, (2) the optimization of abort trajectories which minimize the descent heat load to the aircraft, and (3) fail-safe thermostructural concepts to minimize both the weight and the maximum temperature the structure will reach during descent. These factors are examined and promising approaches are evaluated based on weight, reliability, ease of manufacture and cost.

Characterizing the load environment of ferry landings for Washington State ferries and the Alaska Marine Highway System.

DOT National Transportation Integrated Search

2013-05-01

Anybody riding a ferry wants it to dock safely and for port managers, having passengers and : goods in the water is never a good thing. This project aims to mitigate uncertainty and : assumptions about load demands on ferry terminal structures, s...

Characterizing the load environment of ferry landings for Washington State ferries and the Alaska Marine Highway System.

DOT National Transportation Integrated Search

2012-05-01

Anybody riding a ferry wants it to dock safely and for port managers, having passengers and goods in the water is never a good thing. This project aims to mitigate : uncertainty and assumptions about load demands on ferry terminal structures, spe...

A New Biocompatible and Antibacterial Phosphate Free Glass-Ceramic for Medical Applications

NASA Astrophysics Data System (ADS)

Cabal, Belén; Alou, Luís; Cafini, Fabio; Couceiro, Ramiro; Sevillano, David; Esteban-Tejeda, Leticia; Guitián, Francisco; Torrecillas, Ramón; Moya, José S.

2014-06-01

In the attempt to find valid alternatives to classic antibiotics and in view of current limitations in the efficacy of antimicrobial-coated or loaded biomaterials, this work is focused on the development of a new glass-ceramic with antibacterial performance together with safe biocompatibility. This bactericidal glass-ceramic composed of combeite and nepheline crystals in a residual glassy matrix has been obtained using an antimicrobial soda-lime glass as a precursor. Its inhibitory effects on bacterial growth and biofilm formation were proved against five biofilm-producing reference strains. The biocompatibility tests by using mesenchymal stem cells derived from human bone indicate an excellent biocompatibility.

A New Biocompatible and Antibacterial Phosphate Free Glass-Ceramic for Medical Applications

PubMed Central

Cabal, Belén; Alou, Luís; Cafini, Fabio; Couceiro, Ramiro; Sevillano, David; Esteban-Tejeda, Leticia; Guitián, Francisco; Torrecillas, Ramón; Moya, José S.

2014-01-01

In the attempt to find valid alternatives to classic antibiotics and in view of current limitations in the efficacy of antimicrobial-coated or loaded biomaterials, this work is focused on the development of a new glass-ceramic with antibacterial performance together with safe biocompatibility. This bactericidal glass-ceramic composed of combeite and nepheline crystals in a residual glassy matrix has been obtained using an antimicrobial soda-lime glass as a precursor. Its inhibitory effects on bacterial growth and biofilm formation were proved against five biofilm-producing reference strains. The biocompatibility tests by using mesenchymal stem cells derived from human bone indicate an excellent biocompatibility. PMID:24961911

Development and evaluation of a novel topical treatment for acne with azelaic acid-loaded nanoparticles.

PubMed

Reis, Catarina Pinto; Gomes, Ana; Rijo, Patrícia; Candeias, Sara; Pinto, Pedro; Baptista, Marina; Martinho, Nuno; Ascensão, Lia

2013-10-01

Azelaic acid (AzA) is used in the treatment of acne. However, side effects and low compliance have been associated with several topical treatments with AzA. Nanotechnology presents a strategy that can overcome these problems. Polymeric nanoparticles can control drug release and targeting and reduce local drug toxicity. The aim of this study was to produce and evaluate an innovative topical treatment for acne with AzA-loaded poly-DL-lactide/glycolide copolymer nanoparticles. A soft white powder of nanoparticles was prepared. The mean size of loaded nanoparticles was < 400 nm and zeta potential was negative. Spherical nanoparticles were observed by scanning electron microscopy. Encapsulation efficiency was around 80% and a strong interaction between the polymer and the drug was confirmed by differential scanning calorimetric analysis. In vitro drug release studies suggested a controlled and pulsatile release profile. System efficacy tests suggested similar results between the loaded nanoparticles and the nonencapsulated drug against the most common bacteria associated with acne. Cytotoxicity of AzA-loaded nanoparticles was concentration dependent, although not pronounced. The occluded patch test seemed to indicate that the formulation excipients were safe and thus AzA-loaded nanoparticles appear to be an efficient and safe treatment for acne.

Maximizing Efficiency and Reducing Robotic Surgery Costs Using the NASA Task Load Index.

PubMed

Walters, Carrie; Webb, Paula J

2017-10-01

Perioperative leaders at our facility were struggling to meet efficiency targets for robotic surgery procedures while also maintaining the satisfaction of the surgical team. We developed a human resources time and motion study tool and used it in conjunction with the NASA Task Load Index to observe and analyze the required workload of personnel assigned to 25 robotic surgery procedures. The time and motion study identified opportunities to enlist the help of nonlicensed support personnel to ensure safe patient care and improve OR efficiency. Using the NASA Task Load Index demonstrated that high temporal, effort, and physical demands existed for personnel assisting with and performing robotic surgery. We believe that this process could be used to develop cost-effective staffing models, resulting in safe and efficient care for all surgical patients. Copyright © 2017 AORN, Inc. Published by Elsevier Inc. All rights reserved.

Crane-Load Contact Sensor

NASA Technical Reports Server (NTRS)

Youngquist, Robert; Mata, Carlos; Cox, Robert

2005-01-01

An electronic instrument has been developed as a prototype of a portable crane-load contact sensor. Such a sensor could be helpful in an application in which the load rests on a base in a horizontal position determined by vertical alignment pins (see Figure 1). If the crane is not positioned to lift the load precisely vertically, then the load can be expected to swing once it has been lifted clear of the pins. If the load is especially heavy, large, and/or fragile, it could hurt workers and/or damage itself and nearby objects. By indicating whether the load remains in contact with the pins when it has been lifted a fraction of the length of the pins, the crane-load contact sensor helps the crane operator determine whether it is safe to lift the load clear of the pins: If there is contact, then the load is resting against the sides of the pins and, hence, it may not be safe to lift; if contact is occasionally broken, then the load is probably not resting against the pins, so it should be safe to lift. It is assumed that the load and base, or at least the pins and the surfaces of the alignment holes in the load, are electrically conductive, so the instrument can use electrical contact to indicate mechanical contact. However, DC resistance cannot be used as an indicator of contact for the following reasons: The load and the base are both electrically grounded through cables (the load is grounded through the lifting cable of the crane) to prevent discharge of static electricity. In other words, the DC resistance between the load and the pins is always low, as though they were always in direct contact. Therefore, instead of DC resistance, the instrument utilizes the AC electrical impedance between the pins and the load. The signal frequency used in the measurement is high enough (.1 MHz) that the impedance contributed by the cables and the electrical ground network of the building in which the crane and the base are situated is significantly greater than the contact impedance between the pins and the load. The instrument includes a signal generator and voltage-measuring circuitry, and is connected to the load and the base as shown in Figure 2. The output of the signal generator (typically having amplitude of the order of a volt) is applied to the load via a 50-resistor, and the voltage between the load and the pins is measured. When the load and the pins are not in contact, the impedance between them is relatively high, causing the measured voltage to exceed a threshold value. When the load and the pins are in contact, the impedance between them falls to a much lower value, causing the voltage to fall below the threshold value. The voltage-measuring circuitry turns on a red light-emitting diode (LED) to indicate the lower-voltage/ contact condition. Whenever the contact has been broken and the non-contact/higher-voltage condition has lasted for more than 2 ms, the voltage-measuring circuitry indicates this condition by blinking a green LED.

Interactions Between Modality of Working Memory Load and Perceptual Load in Distractor Processing.

PubMed

Koshino, Hideya; Olid, Pilar

2015-01-01

The present study investigated interactions between working memory load and perceptual load. The load theory (Lavie, Hirst, de Fockert, & Viding, 2004 ) claims that perceptual load decreases distractor interference, whereas working memory load increases interference. However, recent studies showed that effects of working memory might depend on the relationship between modalities of working memory and task stimuli. Here, we examined whether the relationship between working memory load and perceptual load would remain the same across modalities. The results of Experiment 1 showed that verbal working memory load did not affect a compatibility effect for low perceptual load, whereas it increased the compatibility effect for high perceptual load. In Experiment 2, the compatibility effect remained the same regardless of visual working memory load. These results suggest that the effects of working memory load and perceptual load depend on the relationship between the modalities of working memory and stimuli.

Investigations on clonazepam-loaded polymeric micelle-like nanoparticles for safe drug administration during pregnancy.

PubMed

Sezgin-Bayindir, Zerrin; Elcin, Ayse Eser; Parmaksiz, Mahmut; Elcin, Yasar Murat; Yuksel, Nilufer

2018-03-01

Medication during pregnancy is often a necessity for women to treat their acute or chronic diseases. The goal of this study is to evaluate the potential of micelle-like nanoparticles (MNP) for providing safe drug usage in pregnancy and protect both foetus and mother from medication side effects. Clonazepam-loaded MNP were prepared from copolymers [polystyrene-poly(acrylic acid) (PS-PAA), poly(ethylene glycol)-b-poly(lactic acid) (PEG-PLA) and distearyl-sn-glycero-3-phosphoethanolamine-N-[methoxy-poly(ethylene glycol) (PEG-DSPE)] with varying monomer ratios and their drug-loading efficiency, drug release ratio, particle size, surface charge and morphology were characterised. The cellular transport and cytotoxicity experiments were conducted on clonazepam and MNP formulations using placenta-choriocarcinoma-BeWo and brain-endothelial-bEnd3 cells. Clonazepam-loaded PEG 5000 -PLA 4500 MNP reduced the drug transport through BeWo cells demonstrating that MNP may lower foetal drug exposure, thus reduce the drug side effects. However, lipofectamine modified MNP improved the transport of clonazepam and found to be promising for brain and in-utero-specific drug treatment.

Working with Self-Injurious Adolescents Using the Safe Kit

ERIC Educational Resources Information Center

Moyer, Michael

2008-01-01

This article offers a guide for using the Safe Kit when working with clients who self-injure. The Safe Kit can be used as a supplement to more traditional approaches to counseling and offers clients alternatives to self-injury when they need alternatives the most. The Safe Kit works under the assumption that individuals differ in the meaning they…

Application of Multiplexed FBG and PZT Impedance Sensors for Health Monitoring of Rocks.

PubMed

Yang, Yaowen; Annamdas, Venu Gopal Madhav; Wang, Chao; Zhou, Yingxin

2008-01-21

Reliable structural health monitoring (SHM) including nondestructiveevaluation (NDE) is essential for safe operation of infrastructure systems. Effectivemonitoring of the rock components of civil infrastructures such as tunnels and cavernsremains challenging. The feasibility of employing smart optical fibre sensor (OFS) andpiezoelectric impedance sensor made up of lead zirconate titanate (PZT) forcomprehensive health monitoring of rocks, covering load history monitoring/retrieval aswell as damage assessment is presented in this paper. The rock specimens are subjected tocyclic loading and their conditions are continuously monitored using OFS and PZTsensors. OFS based multiplexed fibre Bragg grating (FBG) sensors are surface bonded onthe rock specimens. Their strain sensing performance is compared with the conventionalelectric strain gauges (ESGs). In addition, PZT patches are also bonded on the specimensto study the damage pattern during different loading cycles. Unlike the FBGs or ESGs,PZT patches are used as bi-functional sensors and actuators, enabling them to be efficientdetectors of incipient damages using the principle of electromechanical impedance. Theexperimental study demonstrated superior performance of these smart FBG and PZTimpedance sensors. This work is expected to be useful for SHM based NDE application ofrock structures such as caverns and tunnels.

Study of a fail-safe abort system for an actively cooled hypersonic aircraft. Volume 1: Technical summary

NASA Technical Reports Server (NTRS)

Pirello, C. J.; Herring, R. L.

1976-01-01

Conceptual designs of a fail-safe abort system for hydrogen fueled actively cooled high speed aircraft are examined. The fail-safe concept depends on basically three factors: (1) a reliable method of detecting a failure or malfunction in the active cooling system, (2) the optimization of abort trajectories which minimize the descent heat load to the aircraft, and (3) fail-safe thermostructural concepts to minimize both the weight and the maximum temperature the structure will reach during descent. These factors are examined and promising approaches are evaluated based on weight, reliability, ease of manufacture and cost.

Mechanical evaluation of external skeletal fixator-intramedullary pin tie-in configurations applied to cadaveral humeri from red-tailed hawks (Buteo jamaicensis).

PubMed

Van Wettere, Arnaud J; Redig, Patrick T; Wallace, Larry J; Bourgeault, Craig A; Bechtold, Joan E

2009-12-01

Use of external skeletal fixator-intramedullary pin (ESF-IM) tie-in fixators is an adjustable and effective method of fracture fixation in birds. The objective of this study was to determine the contribution of each of the following parameters to the compressive and torsional rigidity of an ESF-IM pin tie-in applied to avian bones with an osteotomy gap: (1) varying the fixation pin position in the proximal bone segment and (2) increasing the number of fixation pins in one or both bone segments. ESF-IM pin tie-in constructs were applied to humeri harvested from red-tailed hawks (Buteo jamaicensis) (n=24) that had been euthanatized for clinical reasons. Constructs with a variation in the placement of the proximal fixation pin and with 2, 3, or 4 fixation pins applied to avian bone with an osteotomy gap were loaded to a defined displacement in torque and axial compression. Response variables were determined from resulting load-displacement curves (construct stiffness, load at 1-mm displacement). Increasing the number of fixation pins from 1 to 2 per bone segment significantly increased the stiffness in torque (110%) and compression (60%), and the safe load in torque (107%) and compression (50%). Adding a fixation pin to the distal bone segment to form a 3-pin fixator significantly increased the stiffness (27%) and safe load (20%) in torque but not in axial compression. In the configuration with 2 fixation pins, placing the proximal pin distally in the proximal bone segment significantly increased the stiffness in torque (28%), and the safe load in torque (23%) and in axial compression (32%). Results quantified the relative importance of specific parameters affecting the rigidity of ESF-IM pin tie-in constructs as applied to unstable bone fracture models in birds.

Automated assembly of microfluidic "lab-on-a-disc"

NASA Astrophysics Data System (ADS)

Berger, M.; Müller, T.; Voebel, T.; Baum, C.; Glennon, T.; Mishra, R.; Kinahan, D.; King, D.; Ducrée, J.; Brecher, C.

2018-02-01

Point-of-care (POC) testing attracts more and more attention in the medical health sector because of their specific property to perform the diagnostic close to the patient. The fast diagnosis right at the hospital or the doctor's office improves the medical reaction time and the chances for a successful healing process. One of this POC test systems is a "Lab-on-a-Disc" (LoaD) which looks like a compact disc crisscrossed with microfluidic tubes and cavities. The fluid to be analysed is placed in the LoaD and an external device then rotates the LoaD. The cavities inside the LoaD and the centrifugal force ensure a clearly defined sequence of the analysis. Furthermore, we aim for an inexpensive manufacture of the medical product without neglecting its quality and functionality. Therefore, the Fraunhofer IPT works on an assembly cell to implement dissoluble films concisely into the disc. This dissoluble film demonstrates its successful usage as a gate for the fluid, which opens after a predefined moment in the cycle. Furthermore, we investigate to integrate a laser welding process into our gantry system and demonstrate its efficiency with the welding of polymer discs. This procedure is clinically safe because no further laser absorption material is needed in the sealing process, which might pollute the LoaD. Moreover, this process allows the alignment of several discs before the welding and therefore leads to precisely manufactured LoaDs in large quantities. All these methods together enable a fast, costefficient and reliable mass production to bring POC testing among the people.

Field Testing and Load Rating Report for Bridge No. 4, Hybrid Composite Beam Span, at Fort Knox, Kentucky

DTIC Science & Technology

2016-09-01

required load rating (HL-93) and performance criteria for deflection and strain. Results showed the bridge met all design specifications and load...their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by...composite beams met design specifications and could deliver safe crossing of Heavy Equipment Transport System (HETS-115) vehicles. Their report

Comparative analysis on flexibility requirements of typical Cryogenic Transfer lines

NASA Astrophysics Data System (ADS)

Jadon, Mohit; Kumar, Uday; Choukekar, Ketan; Shah, Nitin; Sarkar, Biswanath

2017-04-01

The cryogenic systems and their applications; primarily in large Fusion devices, utilize multiple cryogen transfer lines of various sizes and complexities to transfer cryogenic fluids from plant to the various user/ applications. These transfer lines are composed of various critical sections i.e. tee section, elbows, flexible components etc. The mechanical sustainability (under failure circumstances) of these transfer lines are primary requirement for safe operation of the system and applications. The transfer lines need to be designed for multiple design constraints conditions like line layout, support locations and space restrictions. The transfer lines are subjected to single load and multiple load combinations, such as operational loads, seismic loads, leak in insulation vacuum loads etc. [1]. The analytical calculations and flexibility analysis using professional software are performed for the typical transfer lines without any flexible component, the results were analysed for functional and mechanical load conditions. The failure modes were identified along the critical sections. The same transfer line was then refurbished with the flexible components and analysed for failure modes. The flexible components provide additional flexibility to the transfer line system and make it safe. The results obtained from the analytical calculations were compared with those obtained from the flexibility analysis software calculations. The optimization of the flexible component’s size and selection was performed and components were selected to meet the design requirements as per code.

A novel liquid organic hydrogen carrier system based on catalytic peptide formation and hydrogenation

PubMed Central

Hu, Peng; Fogler, Eran; Diskin-Posner, Yael; Iron, Mark A.; Milstein, David

2015-01-01

Hydrogen is an efficient green fuel, but its low energy density when stored under high pressure or cryogenically, and safety issues, presents significant disadvantages; hence finding efficient and safe hydrogen carriers is a major challenge. Of special interest are liquid organic hydrogen carriers (LOHCs), which can be readily loaded and unloaded with considerable amounts of hydrogen. However, disadvantages include high hydrogen pressure requirements, high reaction temperatures for both hydrogenation and dehydrogenation steps, which require different catalysts, and high LOHC cost. Here we present a readily reversible LOHC system based on catalytic peptide formation and hydrogenation, using an inexpensive, safe and abundant organic compound with high potential capacity to store and release hydrogen, applying the same catalyst for loading and unloading hydrogen under relatively mild conditions. Mechanistic insight of the catalytic reaction is provided. We believe that these findings may lead to the development of an inexpensive, safe and clean liquid hydrogen carrier system. PMID:25882348

Blast Upgrading of Existing Structures

DTIC Science & Technology

1979-01-01

covered with soil, the response is different from triat when subjected to a blast load . Table 2-3 is a summary of the maxi- mum load bearing ... load ) 5 W14 384 El =5 (40) 16 (192)3 394 x 1.85 x 106 x 98.93 6 =0.32 0.53 O.K. Bearing at-Support = 3.5 1.5 = 2 in. 2 l° MIST f L V 533 f 7 psi < 4-s...10 psf dead load (91 psf live load ). Shear fv = 2.03(51.6) = 105 psi, and bearing fc= 2.03 (178) are = 361 psi well within conventional ,safe limits

The perceived compatibility of safety and production expectations in hazardous occupations.

PubMed

McLain, David L; Jarrell, Kimberly A

2007-01-01

Safety hazards are unavoidable in many work environments. Employees must be both productive and safe, however, conflicting safety and production demands can negatively affect safety, production, or both. The employee's perception of the compatibility of management's safety and production expectations is a possible predictor of such consequences. This paper defines "safety-production compatibility" and describes how measures of safety-production compatibility, as well as safety pressure and production pressure, were developed. We used LISREL structural equation modeling to test the influences of safety-production compatibility, safety pressure, and production pressure on safe work behavior and interference with performing other work tasks. The 239 study participants were workers employed in diverse but hazardous occupations. Pressure to work safely was positively associated with safe work behavior. The perceived compatibility of safety and production demands positively influenced safe work behavior and reduced the interference of safety hazards performing other tasks. Safety-production compatibility was also found to mediate the relationship between trust in management and safe work behavior. The results of this field study suggest increased compatibility, and thus less conflict, between safety and production demands influences safe work behavior and the interference of safety hazards with performing other work tasks. More broadly, the worker's reaction to multiple work demands is a safety and performance influence. Safety management efforts that focus only on the hazards fail to eliminate many accidents because accidents arise from many factors including technology, safety climate, social influences, production, and safety demands. This study suggests that workers differ in their perception of the compatibility of safety and production demands. These differences will show up in safe work behavior, influencing the effectiveness of safety management efforts and the trust workers have in management's concern for safety.

Effects of wet mat curing time and earlier loading on long-term durability of bridge decks : compressive strength, maturity and strength durability index (SDI).

DOT National Transportation Integrated Search

2009-01-01

There is increasing pressure from owners, contractors, and the public to open bridge decks sooner to full : traffic loads. As a result, a set of criteria or guidelines is needed to determine when concrete bridge decks can : safely be opened. Today, c...

78 FR 35087 - Parts and Accessories Necessary for Safe Operation; Exemption Renewal for the Flatbed Carrier...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-11

... intermodal container loaded with eyes crosswise, grouped in rows, in which the coils are loaded to contact... cargo securement regulations for the transportation of groups of metal coils with eyes crosswise, as... cargo securement regulations (then at 49 CFR 393.100(c)) for the transportation of groups of metal coils...

Screening the working environment in outdoor pig systems.

PubMed

Geng, Q; Torén, A; Salomon, E

2009-07-01

This study investigated how well organic growing-fattening pig systems provided a safe and healthy working environment and identified areas where improvements are needed. The study formed part of a larger project aimed at identifying strategies for creating a good animal and working environment and resource-efficient nutrient management in outdoor pig systems. Field studies were carried out at six Swedish farms in two types of outdoor pig systems (mobile and stationary). A method known as WEST (Work Environment Screening Tool) and a modified version of WEST, called WEST-agriculture (WEST-AG), were utilized for screening. Together, the two methods covered six factors of the working environment. The results were expressed in WEST-AG points and WEST points, an economic measure of the risk of impacts on health and productivity expressed as Swedish Krona (SEK) per thousand working hours. The results demonstrated that the risk of injury and ergonomic load during manual feeding and watering was much higher than during semi-automatic feeding and watering at farms with the mobile system. The study also identified other health-risk areas and provided valuable information for further improvement of the working environment in different outdoor pig systems.

Redesign of solid rocket booster/external tank attachment ring for the space transportation system

NASA Technical Reports Server (NTRS)

Mccomb, Harvey G., Jr. (Compiler)

1987-01-01

An improved design concept is presented for the Space Shuttle solid rocket booster (SRB)/external tank (ET) attachment ring structural component. This component picks up three struts which attach the aft end of each SRB to the ET. The concept is a partial ring with carefully tapered ends to distribute fastener loads safely into the SRB. Extensive design studies and analyses were performed to arrive at the concept. Experiments on structural elements were performed to determine material strength and stiffness characteristics. Materials and fabrication studies were conducted to determine acceptable tolerances for the design concept. An overview is provided of the work along with conclusions and major recommendations.

Review of fatigue and fracture research at NASA Langley Research Center

NASA Technical Reports Server (NTRS)

Everett, Richard A., Jr.

1988-01-01

Most dynamic components in helicopters are designed with a safe-life constant-amplitude testing approach that has not changed in many years. In contrast, the fatigue methodology in other industries has advanced significantly in the last two decades. Recent research at the NASA Langley Research Center and the U.S. Army Aerostructures Directorate at Langley are reviewed relative to fatigue and fracture design methodology for metallic components. Most of the Langley research was directed towards the damage tolerance design approach, but some work was done that is applicable to the safe-life approach. In the areas of testing, damage tolerance concepts are concentrating on the small-crack effect in crack growth and measurement of crack opening stresses. Tests were conducted to determine the effects of a machining scratch on the fatigue life of a high strength steel. In the area of analysis, work was concentrated on developing a crack closure model that will predict fatigue life under spectrum loading for several different metal alloys including a high strength steel that is often used in the dynamic components of helicopters. Work is also continuing in developing a three-dimensional, finite-element stress analysis for cracked and uncracked isotropic and anisotropic structures. A numerical technique for solving simultaneous equations called the multigrid method is being pursued to enhance the solution schemes in both the finite-element analysis and the boundary element analysis. Finally, a fracture mechanics project involving an elastic-plastic finite element analysis of J-resistance curve is also being pursued.

Using ergonomics to enhance safe production at a surface coal mine--a case study with powder crews.

PubMed

Torma-Krajewski, Janet; Wiehagen, William; Etcheverry, Ann; Turin, Fred; Unger, Richard

2009-10-01

Job tasks that involve exposure to work-related musculoskeletal disorder (WMSD) risk factors may impact both the risk of injury and production downtime. Common WMSD risks factors associated with mining tasks include forceful exertions, awkward postures, repetitive motion, jolting and jarring, forceful gripping, contact stress, and whole body and segmental vibration. Mining environments that expose workers to temperature/humidity extremes, windy conditions, and slippery and uneven walking surfaces also contribute to injury risk. National Institute for Occupational Safety and Health (NIOSH) researchers worked with powder crew members from the Bridger Coal Company to identify and rank routine work tasks based on perceived exposure to WMSD risk factors. This article presents the process followed to identify tasks that workers believed involved the greatest exposure to risk factors and discusses risk reduction strategies. Specifically, the proposed prill truck design changes addressed cab ingress/egress, loading blast holes, and access to the upper deck of the prill truck.

40 CFR 82.156 - Required practices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the additional time needed to conduct and complete repairs in a safe working environment will be... creating a safe working environment will require more than 30 weeks; (B) The operator notifies EPA within... the additional time needed to conduct and complete work in a safe environment will be permitted. (iii...

Cost-effectiveness of oral phenytoin, intravenous phenytoin, and intravenous fosphenytoin in the emergency department.

PubMed

Rudis, Maria I; Touchette, Daniel R; Swadron, Stuart P; Chiu, Amy P; Orlinsky, Michael

2004-03-01

Oral phenytoin, intravenous phenytoin, and intravenous fosphenytoin are all commonly used for loading phenytoin in the emergency department (ED). The cost-effectiveness of each was compared for patients presenting with seizures and subtherapeutic phenytoin concentrations. A simple decision tree was developed to determine the treatment costs associated with each of 3 loading techniques. We determined effectiveness by comparing adverse event rates and by calculating the time to safe ED discharge. Time to safe ED discharge was defined as the time at which therapeutic concentrations of phenytoin (>or=10 mg/L) were achieved with an absence of any adverse events that precluded discharge. The comparative cost-effectiveness of alternatives to oral phenytoin was determined by combining net costs and number of adverse events, expressed as cost per adverse events avoided. Cost-effectiveness was also determined by comparing the net costs of each loading technique required to achieve the time to safe ED discharge, expressed as cost per hour of ED time saved. The outcomes and costs were primarily derived from a prospective, randomized controlled trial, augmented by time-motion studies and alternate-cost sources. Costs included the cost of drugs, supplies, and personnel. Analyses were also performed in scenarios incorporating labor costs and savings from using a lower-urgency area of the ED. The mean number of adverse events per patient for oral phenytoin, intravenous phenytoin, and intravenous fosphenytoin was 1.06, 1.93, and 2.13, respectively. Mean time to safe ED discharge in the 3 groups was 6.4 hours, 1.7 hours, and 1.3 hours. Cost per patient was 2.83 dollars, 21.16 dollars, and 175.19 dollars, respectively, and did not differ substantially in the Labor and Triage (lower-urgency area of ED) scenarios. When the measure of effectiveness was adverse events, oral phenytoin dominated intravenous phenytoin and intravenous fosphenytoin, with a lower cost and number of adverse events. With time to safe ED discharge as the outcome measure, the incremental cost-effectiveness ratios were 3.90 dollars and 387.27 dollars per hour of ED time saved for oral phenytoin versus intravenous phenytoin and for intravenous fosphenytoin versus intravenous phenytoin, respectively. Oral phenytoin is the most cost-effective loading method in most settings. Intravenous phenytoin is preferred if one is willing to pay an additional 20.65 dollars to 44.25 dollars per patient and willing to have more adverse events for a quicker average time to safe ED discharge. It is unlikely that intravenous fosphenytoin is justifiable in any setting.

[DETERMINATION OF THE OPTIMAL SAFE MODE OF PHYSICAL ACTIVITY FOR THE MILITARY SERVANTS UNDER CONDITIONS CLOSE TO FIGHTING].

PubMed

Chernozub, A; Radchenko, Y

2015-01-01

The paper presents the results of research, allowing to establish the need for and feasibility of an integrated method to determine the most effective but at the same time safe modes of load to the body troops. We found that despite the rather promising application of our proposed mode of load of high intensity (Ra = 0.71) to increase the level of physical military training as soon as possible in time of peace (with a minimum set of combat equipment), problematic issue is that in most cases there is a complete-mismatch achieved in the degree of physical development of the body of military requirements and the challenges posed in terms of direct hostilities. Using the integral method developed by us we determine the safest modes of exercise for the military servants to optimize the most appropriate parameters of volume and intensity of the load, and speed up the adaptive changes in their body to enhance maximum performance at this stage of preparation.

Rapidly separating microneedles for transdermal drug delivery.

PubMed

Zhu, Dan Dan; Wang, Qi Lei; Liu, Xu Bo; Guo, Xin Dong

2016-09-01

The applications of polymer microneedles (MNs) into human skin emerged as an alternative of the conventional hypodermic needles. However, dissolving MNs require many minutes to be dissolved in the skin and typically have difficulty being fully inserted into the skin, which may lead to the low drug delivery efficiency. To address these issues, we introduce rapidly separating MNs that can rapidly deliver drugs into the skin in a minimally invasive way. For the rapidly separating MNs, drug loaded dissolving MNs are mounted on the top of solid MNs, which are made of biodegradable polylactic acid which eliminate the biohazardous waste. These MNs have sufficient mechanical strength to be inserted into the skin with the drug loaded tips fully embedded for subsequent dissolution. Compared with the traditional MNs, rapidly separating MNs achieve over 90% of drug delivery efficiency in 30s while the traditional MNs needs 2min to achieve the same efficiency. With the in vivo test in mice, the micro-holes caused by rapidly separating MNs can heal in 1h, indicating that the rapidly separating MNs are safe for future applications. These results indicate that the design of rapidly separating dissolvable MNs can offer a quick, high efficient, convenient, safe and potentially self-administered method of drug delivery. Polymer microneedles offer an attractive, painless and minimally invasive approach for transdermal drug delivery. However, dissolving microneedles require many minutes to be dissolved in the skin and typically have difficulty being fully inserted into the skin due to the skin deformation, which may lead to the low drug delivery efficiency. In this work we proposed rapidly separating microneedles which can deliver over 90% of drug into the skin in 30s. The in vitro and in vivo results indicate that the new design of these microneedles can offer a quick, high efficient, convenient and safe method for transdermal drug delivery. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Occupational health and safety aspects of animal handling in dairy production.

PubMed

Lindahl, Cecilia; Lundqvist, Peter; Hagevoort, G Robert; Lunner Kolstrup, Christina; Douphrate, David I; Pinzke, Stefan; Grandin, Temple

2013-01-01

Livestock handling in dairy production is associated with a number of health and safety issues. A large number of fatal and nonfatal injuries still occur when handling livestock. The many animal handling tasks on a dairy farm include moving cattle between different locations, vaccination, administration of medication, hoof care, artificial insemination, ear tagging, milking, and loading onto trucks. There are particular problems with bulls, which continue to cause considerable numbers of injuries and fatalities in dairy production. In order to reduce the number of injuries during animal handling on dairy farms, it is important to understand the key factors in human-animal interactions. These include handler attitudes and behavior, animal behavior, and fear in cows. Care when in close proximity to the animal is the key for safe handling, including knowledge of the flight zone, and use of the right types of tools and suitable restraint equipment. Thus, in order to create safe working conditions during livestock handling, it is important to provide handlers with adequate training and to establish sound safety management procedures on the farm.

The Lead-Safe Certified Guide to Renovate Right

MedlinePlus

... for information about courses and resources on lead-safe work practices. 1 RENOVAT ING, REPA IRING, OR PA ... child care facility or school. • Always use lead-safe work practices when renovation or repair will disturb painted ...

Optimal acetabular component orientation estimated using edge-loading and impingement risk in patients with metal-on-metal hip resurfacing arthroplasty.

PubMed

Mellon, Stephen J; Grammatopoulos, George; Andersen, Michael S; Pandit, Hemant G; Gill, Harinderjit S; Murray, David W

2015-01-21

Edge-loading in patients with metal-on-metal resurfaced hips can cause high serum metal ion levels, the development of soft-tissue reactions local to the joint called pseudotumours and ultimately, failure of the implant. Primary edge-loading is where contact between the femoral and acetabular components occurs at the edge/rim of the acetabular component whereas impingement of the femoral neck on the acetabular component's edge causes secondary or contrecoup edge-loading. Although the relationship between the orientation of the acetabular component and primary edge-loading has been identified, the contribution of acetabular component orientation to impingement and secondary edge-loading is less clear. Our aim was to estimate the optimal acetabular component orientation for 16 metal-on-metal hip resurfacing arthroplasty (MoMHRA) subjects with known serum metal ion levels. Data from motion analysis, subject-specific musculoskeletal modelling and Computed Tomography (CT) measurements were used to calculate the dynamic contact patch to rim (CPR) distance and impingement risk for 3416 different acetabular component orientations during gait, sit-to-stand, stair descent and static standing. For each subject, safe zones free from impingement and edge-loading (CPR <10%) were defined and, consequently, an optimal acetabular component orientation was determined (mean inclination 39.7° (SD 6.6°) mean anteversion 14.9° (SD 9.0°)). The results of this study suggest that the optimal acetabular component orientation can be determined from a patient's motion and anatomy. However, 'safe' zones of acetabular component orientation associated with reduced risk of dislocation and pseudotumour are also associated with a reduced risk of edge-loading and impingement. Copyright © 2014 Elsevier Ltd. All rights reserved.

Cold Expansion Effects on Cracked Fastener Holes Under Constant Amplitude and Spectrum Loading in the 2024-T351 Aluminum Alloy

DTIC Science & Technology

2012-05-01

1 1.2. History of Fatigue Designs ................................................................................... 2 1.3...of design . 1.2. History of Fatigue Designs 1.2.1. Safe Life Design The United States Air Force (USAF) has primarily used two design paradigms...for fatigue thus far. These paradigms are the Safe Life, and the Damage Tolerance fatigue designs . The American Society for Metals (ASM) Handbook

DroidSafe

DTIC Science & Technology

2016-12-01

branches of our work . 3.1 Understanding Sensitive API Call and API Information Usage Android applications are written in a type- safe language (Java...directly invoke resolved targets. Because DroidSafe works with a comprehensive model of the Android environment , it supports precise resolution of...STATEMENT. FOR THE CHIEF ENGINEER: / S / / S / MARK K. WILLIAMS WARREN H. DEBANY, JR. Work Unit Manager

Safe Schools, Safe Communities.

ERIC Educational Resources Information Center

Lewis, Julie E.; Pickett, Dean; Pulliam, Janet L.; Schwartz, Richard A.; St. Germaine, Anne-Marie; Underwood, Julie; Worona, Jay

Schools must work together with agencies, groups, and individuals to eliminate the forces leading children to violence. Chapter 1, "School Safety: Working Together to Keep Schools Safe," stresses the importance of community collaboration in violence prevention. Effective prevention requires sharing information about students, consistent…

A novel modeling to predict the critical current behavior of Nb3Sn PIT strand under transverse load based on a scaling law and Finite Element Analysis

NASA Astrophysics Data System (ADS)

Wang, Tiening; Chiesa, Luisa; Takayasu, Makoto; Bordini, Bernardo

2014-09-01

Superconducting Nb3Sn Powder-In-Tube (PIT) strands could be used for the superconducting magnets of the next generation Large Hadron Collider. The strands are cabled into the typical flat Rutherford cable configuration. During the assembly of a magnet and its operation the strands experience not only longitudinal but also transverse load due to the pre-compression applied during the assembly and the Lorentz load felt when the magnets are energized. To properly design the magnets and guarantee their safe operation, mechanical load effects on the strand superconducting properties are studied extensively; particularly, many scaling laws based on tensile load experiments have been established to predict the critical current dependence on strain. However, the dependence of the superconducting properties on transverse load has not been extensively studied so far. One of the reasons is that transverse loading experiments are difficult to conduct due to the small diameter of the strand (about 1 mm) and the data currently available do not follow a common measurement standard making the comparison between different data sets difficult. Recently at the University of Geneva, a new device has been developed to characterize the critical current of Nb3Sn strands under transverse loads. In this work we present a new 2D Finite Element Analysis (FEA) to predict the electro-mechanical response of a PIT strand that was tested at the University of Geneva when transverse load is applied. The FEA provides the strain map for the superconducting filaments when the load is applied. Those strain maps are then used to evaluate the critical current behavior of a PIT strand using a recently developed scaling law that correlates the superconducting properties of a wire with the strain invariants due to the load applied on the superconductor. The benefits and limitations of this method are discussed based on the comparison between the critical current simulation results obtained with the filament strain map and the experimental results available for PIT strands.

The Study of Residual Voltage of Induction Motor and the Influence of Various Parameters on the Residual Voltage

NASA Astrophysics Data System (ADS)

Zhang, Shuping; Zhao, Chen; Tan, Weipu

2017-05-01

The majority important load of industrial area is mainly composed of induction motor, it is more common that induction motor becomes sluggishness and even tripping due to the lose of power supply or other malfunction in the practical work. In this paper, space vector method is used to establish a reduced order model of induction motor, and then study the changes of motor electromagnetic after losing electricity. Based on motion equations of the rotor and magnetic flux conservation principle, it uses mathematical methods to deduce the expression of rotor current, rotor flux, the stator flux and the residual voltage of stator side. In addition, relying on thermal power plants, it uses the actual data of power plants, takes DIgsilent software to simulate the residual voltage of motor after losing electricity. analyses the influence on the residual voltage with the changes of the moment of inertia, load ratio, initial size of slip and the load characteristic of induction motor. By analysis of these, it has a more detailed understanding about the changes of residual voltage in practical application, in additional, it is more beneficial to put into standby power supply safely and effectively, moreover, reduce the influence of the input process to the whole system.

Application of Multiplexed FBG and PZT Impedance Sensors for Health Monitoring of Rocks

PubMed Central

Yang, Yaowen; Annamdas, Venu Gopal Madhav; Wang, Chao; Zhou, Yingxin

2008-01-01

Reliable structural health monitoring (SHM) including nondestructive evaluation (NDE) is essential for safe operation of infrastructure systems. Effective monitoring of the rock components of civil infrastructures such as tunnels and caverns remains challenging. The feasibility of employing smart optical fibre sensor (OFS) and piezoelectric impedance sensor made up of lead zirconate titanate (PZT) for comprehensive health monitoring of rocks, covering load history monitoring/retrieval as well as damage assessment is presented in this paper. The rock specimens are subjected to cyclic loading and their conditions are continuously monitored using OFS and PZT sensors. OFS based multiplexed fibre Bragg grating (FBG) sensors are surface bonded on the rock specimens. Their strain sensing performance is compared with the conventional electric strain gauges (ESGs). In addition, PZT patches are also bonded on the specimens to study the damage pattern during different loading cycles. Unlike the FBGs or ESGs, PZT patches are used as bi-functional sensors and actuators, enabling them to be efficient detectors of incipient damages using the principle of electromechanical impedance. The experimental study demonstrated superior performance of these smart FBG and PZT impedance sensors. This work is expected to be useful for SHM based NDE application of rock structures such as caverns and tunnels. PMID:27879708

Frequency Splitting Analysis and Compensation Method for Inductive Wireless Powering of Implantable Biosensors.

PubMed

Schormans, Matthew; Valente, Virgilio; Demosthenous, Andreas

2016-08-04

Inductive powering for implanted medical devices, such as implantable biosensors, is a safe and effective technique that allows power to be delivered to implants wirelessly, avoiding the use of transcutaneous wires or implanted batteries. Wireless powering is very sensitive to a number of link parameters, including coil distance, alignment, shape, and load conditions. The optimum drive frequency of an inductive link varies depending on the coil spacing and load. This paper presents an optimum frequency tracking (OFT) method, in which an inductive power link is driven at a frequency that is maintained at an optimum value to ensure that the link is working at resonance, and the output voltage is maximised. The method is shown to provide significant improvements in maintained secondary voltage and system efficiency for a range of loads when the link is overcoupled. The OFT method does not require the use of variable capacitors or inductors. When tested at frequencies around a nominal frequency of 5 MHz, the OFT method provides up to a twofold efficiency improvement compared to a fixed frequency drive. The system can be readily interfaced with passive implants or implantable biosensors, and lends itself to interfacing with designs such as distributed implanted sensor networks, where each implant is operating at a different frequency.

Analysis of situation of rural women in the Lublin Region from the aspect of loading with work.

PubMed

Pawlak, Halina; Maniak, Barbara; Petkowicz, Beata; Kuna-Broniowska, Izabela; Petkowicz, Jacek; Buczaj, Agnieszka

2013-01-01

The objective of the study was recognition of rural women's opinions concerning the degree of heaviness of work activities performed and obtaining the answer to the question: What is the actual level of loading rural women with work? The basic research instrument was a questionnaire form. A representative group of women aged 40-50 were selected for the study because this group had the most complete family structure. The study was conducted among rural women living in the commune of Zwierzyniec. Family size and multi-generationality were analyzed, as well as family members' assistance in household and field activities. The type of work performed was analyzed with consideration of the duration of work and body position while performing this work. Self-reported degree of loading with work on a farm was analyzed, and effective energy expenditure calculated for individual work activities performed by women, based on which the actual degree of loading with work was determined. The respondents generally perceived their loading with work as low. They considered household jobs as not loading with or not exerting any effect on their fatigue and state of health. A very weak statistical relationship was observed between the duration of loading with household jobs and the perceived degree of loading with this work. The Kołmogorov-Smirnov test showed that the evaluations expressed by women concerning the degree of loading with household chores did not depend on time devoted to these work activities. The majority of women similarly evaluated work load, irrespective of the actual degree of loading. Work activities performed in a household were classified according to work load as heavy, medium-heavy and mediocre. Subjective evaluations of work load by rural women considerably differed from the assessment performed using the work time schedule method.

Modeling Operator Performance in Low Task Load Supervisory Domains

DTIC Science & Technology

2011-06-01

PDF Probability Distribution Function SAFE System for Aircrew Fatigue Evaluation SAFTE Sleep , Activity, Fatigue, and Task Effectiveness SCT...attentional capacity due to high mental workload. In low task load settings, fatigue is mainly caused by lack of sleep and boredom experienced by...performance decrements. Also, psychological fatigue is strongly correlated with lack of sleep . Not surprisingly, operators of the morning shift reported the

Concurrent working memory load can facilitate selective attention: evidence for specialized load.

PubMed

Park, Soojin; Kim, Min-Shik; Chun, Marvin M

2007-10-01

Load theory predicts that concurrent working memory load impairs selective attention and increases distractor interference (N. Lavie, A. Hirst, J. W. de Fockert, & E. Viding). Here, the authors present new evidence that the type of concurrent working memory load determines whether load impairs selective attention or not. Working memory load was paired with a same/different matching task that required focusing on targets while ignoring distractors. When working memory items shared the same limited-capacity processing mechanisms with targets in the matching task, distractor interference increased. However, when working memory items shared processing with distractors in the matching task, distractor interference decreased, facilitating target selection. A specialized load account is proposed to describe the dissociable effects of working memory load on selective processing depending on whether the load overlaps with targets or with distractors. (c) 2007 APA

Viscoelastic effects on frequency tuning of a dielectric elastomer membrane resonator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Jianyou; Jiang, Liying, E-mail: lyjiang@eng.uwo.ca; Khayat, Roger E.

2014-03-28

As a recent application of dielectric elastomers (DEs), DE resonators have become an alternative to conventional silicon-based resonators used in MEMS and have attracted much interest from the research community. However, most existing modeling works for the DE resonators ignore the intrinsic viscoelastic effect of the material that may strongly influence their dynamic performance. Based on the finite-deformation viscoelasticity theory for dielectrics, this paper theoretically examines the in-plane oscillation of a DE membrane resonator to demonstrate how the material viscoelasticity affects the actuation and frequency tuning processes of the resonator. From the simulation results, it is concluded that not onlymore » the applied voltage can change the natural frequency of the resonator, but also the inelastic deformation contributes to frequency tuning. Due to the viscoelasticity of the material, the electrical loading rate influences the actuation process of the DE resonator, while it has little effect on the final steady frequency tuned by the prescribed voltage within the safety range. With the consideration of the typical failure modes of the resonator and the evolution process of the material, the tunable frequency range and the safe range of the applied voltage of the DE membrane resonator with different dimension parameters are determined in this work, which are found to be dependent on the electrical loading rate. This work is expected to provide a better understanding on the frequency tuning of viscoelastic DE membrane resonators and a guideline for the design of DE devices.« less

Juvenile idiopathic arthritis and athletic participation: are we adequately preparing for sports integration?

PubMed

Taxter, Alysha; Foss, Kim Barber; Melson, Paula; Ford, Kevin R; Shaffer, Michael; Myer, Gregory D

2012-09-01

Children with juvenile idiopathic arthritis (JIA) now have well-controlled disease due to improved therapies and management strategies. Children with JIA are more active than in the past and often participate in dynamic, high-loading sports. Standard measures of disease control include examination findings, laboratory values, and patient-directed surveys. However, these standards do not address the subtle deficits in biomechanics and neuromuscular control, which could place affected joints at higher risk for injury. Currently, there are limited evidence-based guidelines to structure conditioning recommendations as to the fitness and mechanics needed to provide safe integration into sports in this population; therefore, tools that objectively measure function with high accuracy and precision may be warranted. Previous work using 3-dimensional motion analysis demonstrated usefulness in guiding physical therapy treatment to correct these deficits. The use of a multidisciplinary team, including physical therapy, rheumatology, and sports medicine, is crucial for preparing these children to return to play. We suggest that the child transition into a sport preparatory-conditioning program to address any underlying deficits. A pediatric exercise specialist who is sensitive to the needs of this population can work with a physical therapist to then appropriately integrate the child safely into sport. Encouraging an active lifestyle is vital to the management of JIA and does not worsen the symptoms associated with childhood arthritis.

Coal/rock interface detection by sensitized pick, part A

NASA Technical Reports Server (NTRS)

Wu, P. T. K.; Erkes, J. W.

1981-01-01

In order to increase the operating margins of the detector for safe, reliable operation under difficult in-mine conditions the transmitted signal strength was increased to provide additional signal margin for in-mine conditions and the transmitter section was redesigned to reduce frequency pulling of the transmitter frequency with variations in antenna load. The linearity of the pick load SCO signal with true pick load was increased, and hysteresis effects were minimized. The sensitized pick hardware was ruggedized for rough inmine use. The sensitized pick and telemetry system provided excellent, high quality signals proportional to cutting load under all conditions experienced during testing.

On the monitoring and implications of growing damages caused by manufacturing defects in composite structures

NASA Astrophysics Data System (ADS)

Schagerl, M.; Viechtbauer, C.; Hörrmann, S.

2015-07-01

Damage tolerance is a classical safety concept for the design of aircraft structures. Basically, this approach considers possible damages in the structure, predicts the damage growth under applied loading conditions and predicts the following decrease of the structural strength. As a fundamental result the damage tolerance approach yields the maximum inspection interval, which is the time a damage grows from a detectable to a critical level. The above formulation of the damage tolerance safety concept targets on metallic structures where the damage is typically a simple fatigue crack. Fiber-reinforced polymers show a much more complex damage behavior, such as delaminationsin laminated composites. Moreover, progressive damage in composites is often initiated by manufacturing defects. The complex manufacturing processes for composite structures almost certainly yield parts with defects, e.g. pores in the matrix or undulations of fibers. From such defects growing damages may start after a certain time of operation. The demand to simplify or even avoid the inspection of composite structures has therefore led to a comeback of the traditional safe-life safety concept. The aim of the so-called safe-life flaw tolerance concept is a structure that is capable of carrying the static loads during operation, despite significant damages and after a representative fatigue load spectrum. A structure with this property does not need to be inspected, respectively monitored at all during its service life. However, its load carrying capability is thereby not fully utilized. This article presents the possible refinement of the state-of-the-art safe-life flaw tolerance concept for composite structures towards a damage tolerance approach considering also the influence of manufacturing defects on damage initiation and growth. Based on fundamental physical relations and experimental observations the challenges when developing damage growth and residual strength curves are discussed.

Fracture Testing of Integral Stiffened Structure

NASA Technical Reports Server (NTRS)

Newman, John A.; Smith, Stephen W.; Piascik, Robert S.; Dawicke, David S.; Johnston, William M.; Willard, Scott A.

2008-01-01

Laboratory testing was conducted to evaluate safety concerns for integrally-stiffened tanks that were found to have developed cracks during pressurization testing. Cracks occurred at fastener holes where additional stiffeners were attached to the integrally-stiffened tank structure. Tests were conducted to obtain material properties and to reproduce the crack morphologies that were observed in service to help determine if the tanks are safe for operation. Reproducing the cracking modes observed during pressurization testing required a complex loading state involving both a tensile load in the integrally-stiffened structure and a pin-load at a fastener hole.

Prediction modeling of physiological responses and human performance in the heat with application to space operations

NASA Technical Reports Server (NTRS)

Pandolf, Kent B.; Stroschein, Leander A.; Gonzalez, Richard R.; Sawka, Michael N.

1994-01-01

This institute has developed a comprehensive USARIEM heat strain model for predicting physiological responses and soldier performance in the heat which has been programmed for use by hand-held calculators, personal computers, and incorporated into the development of a heat strain decision aid. This model deals directly with five major inputs: the clothing worn, the physical work intensity, the state of heat acclimation, the ambient environment (air temperature, relative humidity, wind speed, and solar load), and the accepted heat casualty level. In addition to predicting rectal temperature, heart rate, and sweat loss given the above inputs, our model predicts the expected physical work/rest cycle, the maximum safe physical work time, the estimated recovery time from maximal physical work, and the drinking water requirements associated with each of these situations. This model provides heat injury risk management guidance based on thermal strain predictions from the user specified environmental conditions, soldier characteristics, clothing worn, and the physical work intensity. If heat transfer values for space operations' clothing are known, NASA can use this prediction model to help avoid undue heat strain in astronauts during space flight.

Flare system for safe disposal of LNG from a disabled tanker

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1982-12-01

The feasibility of a flare system for the rapid and safe incineration of the cargo of a disabled LNG tanker is evaluated. The project developed design parameters and proof-of-principle investigations of a system for off-loading and flaring LNG from a disabled LNG tanker. The system described offers enough promise to warrant additional investigation, if cargo burning is desired as a way of reducing other possible hazards.

Engineering of small interfering RNA-loaded lipidoid-poly(DL-lactic-co-glycolic acid) hybrid nanoparticles for highly efficient and safe gene silencing: A quality by design-based approach.

PubMed

Thanki, Kaushik; Zeng, Xianghui; Justesen, Sarah; Tejlmann, Sarah; Falkenberg, Emily; Van Driessche, Elize; Mørck Nielsen, Hanne; Franzyk, Henrik; Foged, Camilla

2017-11-01

Safety and efficacy of therapeutics based on RNA interference, e.g., small interfering RNA (siRNA), are dependent on the optimal engineering of the delivery technology, which is used for intracellular delivery of siRNA to the cytosol of target cells. We investigated the hypothesis that commonly used and poorly tolerated cationic lipids might be replaced with more efficacious and safe lipidoids as the lipid component of siRNA-loaded lipid-polymer hybrid nanoparticles (LPNs) for achieving more efficient gene silencing at lower and safer doses. However, formulation design of such a complex formulation is highly challenging due to a strong interplay between several contributing factors. Hence, critical formulation variables, i.e. the lipidoid content and siRNA:lipidoid ratio, were initially identified, followed by a systematic quality-by-design approach to define the optimal operating space (OOS), eventually resulting in the identification of a robust, highly efficacious and safe formulation. A 17-run design of experiment with an I-optimal approach was performed to systematically assess the effect of selected variables on critical quality attributes (CQAs), i.e. physicochemical properties (hydrodynamic size, zeta potential, siRNA encapsulation/loading) and the biological performance (in vitro gene silencing and cell viability). Model fitting of the obtained data to construct predictive models revealed non-linear relationships for all CQAs, which can be readily overlooked in one-factor-at-a-time optimization approaches. The response surface methodology further enabled the identification of an OOS that met the desired quality target product profile. The optimized lipidoid-modified LPNs revealed more than 50-fold higher in vitro gene silencing at well-tolerated doses and approx. a twofold increase in siRNA loading as compared to reference LPNs modified with the commonly used cationic lipid dioleyltrimethylammonium propane (DOTAP). Thus, lipidoid-modified LPNs show highly promising prospects for efficient and safe intracellular delivery of siRNA. Copyright © 2017 Elsevier B.V. All rights reserved.

Steam generator design for solar towers using solar salt as heat transfer fluid

NASA Astrophysics Data System (ADS)

González-Gómez, Pedro Ángel; Petrakopoulou, Fontina; Briongos, Javier Villa; Santana, Domingo

2017-06-01

Since the operation of a concentrating solar power plant depends on the intermittent character of solar energy, the steam generator is subject to daily start-ups, stops and load variations. Faster start-up and load changes increase the plant flexibility and the daily energy production. However, it involves high thermal stresses on thick-walled components. Continuous operational conditions may eventually lead to a material failure. For these reasons, it is important to evaluate the transient behavior of the proposed designs in order to assure the reliability. The aim of this work is to analyze different steam generator designs for solar power tower plants using molten salt as heat transfer fluid. A conceptual steam generator design is proposed and associated heat transfer areas and steam drum size are calculated. Then, dynamic models for the main parts of the steam generator are developed to represent its transient performance. A temperature change rate that ensures safe hot start-up conditions is studied for the molten salt. The thermal stress evolution on the steam drum is calculated as key component of the steam generator.

Upper-stratospheric glider flights for low-g experimentation

NASA Astrophysics Data System (ADS)

Loesch, Adam

Near Space Corporation's fully-operational High Altitude Shuttle System (HASS) consists of a glider carried to 100,000ft by a high altitude balloon. Originally intended to safely return sensitive instrumentation from altitude back to Earth, the glider provides the opportunity to fly ultra-smooth "parabolas" for low-g experimentation. This work models the dynamic behavior of the glider using aerodynamic parameters of a scaled F-4 Phantom to determine the optimal flight path during descent. Low-g parabola and pull-up pairs are flown until the altitude drops below 18km, approaching the maximum altitude of controlled airspace. With this model, it was found that eleven low-g parabolas can be flown to yield 137 seconds of total test time at an average RMS g-loading of 4.9x10 -2. By changing the weighting factor of the merit function, a tradeoff can be made to increase total test time at the expense of increasing g-loading, or vice-versa. A preliminary design exercise for an improved glider is conducted based on lessons learned from the scaled F-4 flight results.

Overview of experimental preparation for the ITER-Like Wall at JET

NASA Astrophysics Data System (ADS)

Jet Efda Contributors Brezinsek, S.; Fundamenski, W.; Eich, T.; Coad, J. P.; Giroud, C.; Huber, A.; Jachmich, S.; Joffrin, E.; Krieger, K.; McCormick, K.; Lehnen, M.; Loarer, T.; de La Luna, E.; Maddison, G.; Matthews, G. F.; Mertens, Ph.; Nunes, I.; Philipps, V.; Riccardo, V.; Rubel, M.; Stamp, M. F.; Tsalas, M.

2011-08-01

Experiments in JET with carbon-based plasma-facing components have been carried out in preparation of the ITER-Like Wall with beryllium main chamber and full tungsten divertor. The preparatory work was twofold: (i) development of techniques, which ensure safe operation with the new wall and (ii) provision of reference plasmas, which allow a comparison of operation with carbon and metallic wall. (i) Compatibility with the W divertor with respect to energy loads could be achieved in N2 seeded plasmas at high densities and low temperatures, finally approaching partial detachment, with only moderate confinement reduction of 10%. Strike-point sweeping increases the operational space further by re-distributing the load over several components. (ii) Be and C migration to the divertor has been documented with spectroscopy and QMBs under different plasma conditions providing a database which will allow a comparison of the material transport to remote areas with metallic walls. Fuel retention rates of 1.0-2.0 × 1021 D s-1 were obtained as references in accompanied gas balance studies.

A study on model fidelity for model predictive control-based obstacle avoidance in high-speed autonomous ground vehicles

NASA Astrophysics Data System (ADS)

Liu, Jiechao; Jayakumar, Paramsothy; Stein, Jeffrey L.; Ersal, Tulga

2016-11-01

This paper investigates the level of model fidelity needed in order for a model predictive control (MPC)-based obstacle avoidance algorithm to be able to safely and quickly avoid obstacles even when the vehicle is close to its dynamic limits. The context of this work is large autonomous ground vehicles that manoeuvre at high speed within unknown, unstructured, flat environments and have significant vehicle dynamics-related constraints. Five different representations of vehicle dynamics models are considered: four variations of the two degrees-of-freedom (DoF) representation as lower fidelity models and a fourteen DoF representation with combined-slip Magic Formula tyre model as a higher fidelity model. It is concluded that the two DoF representation that accounts for tyre nonlinearities and longitudinal load transfer is necessary for the MPC-based obstacle avoidance algorithm in order to operate the vehicle at its limits within an environment that includes large obstacles. For less challenging environments, however, the two DoF representation with linear tyre model and constant axle loads is sufficient.

Integral Battery Power Limiting Circuit for Intrinsically Safe Applications

NASA Technical Reports Server (NTRS)

Burns, Bradley M.; Blalock, Norman N.

2010-01-01

A circuit topology has been designed to guarantee the output of intrinsically safe power for the operation of electrical devices in a hazardous environment. This design uses a MOSFET (metal oxide semiconductor field-effect transistor) as a switch to connect and disconnect power to a load. A test current is provided through a separate path to the load for monitoring by a comparator against a preset threshold level. The circuit is configured so that the test current will detect a fault in the load and open the switch before the main current can respond. The main current passes through the switch and then an inductor. When a fault occurs in the load, the current through the inductor cannot change immediately, but the voltage drops immediately to safe levels. The comparator detects this drop and opens the switch before the current in the inductor has a chance to respond. This circuit protects both the current and voltage from exceeding safe levels. Typically, this type of protection is accomplished by a fuse or a circuit breaker, but in order for a fuse or a circuit breaker to blow or trip, the current must exceed the safe levels momentarily, which may be just enough time to ignite anything in a hazardous environment. To prevent this from happening, a fuse is typically current-limited by the addition of the resistor to keep the current within safe levels while the fuse reacts. The use of a resistor is acceptable for non-battery applications where the wasted energy and voltage drop across the resistor can be tolerated. The use of the switch and inductor minimizes the wasted energy. For example, a circuit runs from a 3.6-V battery that must be current-limited to 200 mA. If the circuit normally draws 10 mA, then an 18-ohm resistor would drop 180 mV during normal operation, while a typical switch (0.02 ohm) and inductor (0.97 ohm) would only drop 9.9 mV. From a power standpoint, the current-limiting resistor protection circuit wastes about 18 times more power than the switch and the inductor configuration. In the fault condition, both the resistor and the inductor react immediately. The resistor reacts by allowing more current to flow and dropping the voltage. Initially, the inductor reacts by dropping the voltage, and then by not allowing the current to change. When the comparator detects the drop in voltage, it opens the switch, thus preventing any further current flow. The inductor alone is not sufficient protection, because after the voltage drop has settled, the inductor would then allow the current to change, in this example, the current would be 3.7 A. In the fault condition, the resistor is flowing 200 mA until the fuse blows (anywhere from 1 ms to 100 s), while the switch and inductor combination is flowing about 2 A test current while monitoring for the fault to be corrected. Finally, as an additional safety feature, the circuit can be configured to hold the switch opened until both the load and source are disconnected.

Feasibility study of solid oxide fuel cell engines integrated with sprinter gas turbines: Modeling, design and control

NASA Astrophysics Data System (ADS)

Jia, Zhenzhong; Sun, Jing; Dobbs, Herb; King, Joel

2015-02-01

Conventional recuperating solid oxide fuel cell (SOFC)/gas turbine (GT) system suffers from its poor dynamic capability and load following performance. To meet the fast, safe and efficient load following requirements for mobile applications, a sprinter SOFC/GT system concept is proposed in this paper. In the proposed system, an SOFC stack operating at fairly constant temperature provides the baseline power with high efficiency while the fast dynamic capability of the GT-generator is fully explored for fast dynamic load following. System design and control studies have been conducted by using an SOFC/GT system model consisting of experimentally-verified component models. In particular, through analysis of the steady-state simulation results, an SOFC operation strategy is proposed to maintain fairly constant SOFC power (less than 2% power variation) and temperature (less than 2 K temperature variation) over the entire load range. A system design procedure well-suited to the proposed system has also been developed to help determining component sizes and the reference steady-state operation line. In addition, control analysis has been studied for both steady-state and transient operations. Simulation results suggest that the proposed system holds the promise to achieve fast and safe transient operations by taking full advantage of the fast dynamics of the GT-generator.

Analysis of Static Load Test of a Masonry Arch Bridge

NASA Astrophysics Data System (ADS)

Shi, Jing-xian; Fang, Tian-tian; Luo, Sheng

2018-03-01

In order to know whether the carrying capacity of the masonry arch bridge built in the 1980s on the shipping channel entering and coming out of the factory of a cement company can meet the current requirements of Level II Load of highway, through the equivalent load distribution of the test vehicle according to the current design specifications, this paper conducted the load test, evaluated the bearing capacity of the in-service stone arch bridge, and made theoretical analysis combined with Midas Civil. The results showed that under the most unfavorable load conditions the measured strain and deflection of the test sections were less than the calculated values, the bridge was in the elastic stage under the design load; the structural strength and stiffness of the bridge had a certain degree of prosperity, and under the in the current conditions of Level II load of highway, the bridge structure was in a safe state.

Dynamic strength of cylindrical fiber-glass shells and basalt plastic shells under multiple explosive loading

NASA Astrophysics Data System (ADS)

Syrunin, M. A.; Fedorenko, A. G.

2006-08-01

We have shown experimentally that, for cylindrical shells made of oriented fiberglass platic and basalt plastic there exists a critical level of deformations, at which a structure sustains a given number of explosions from the inside. The magnitude of critical deformation for cylindrical fiberglass shells depends linearly on the logarithm of the number of loads that cause failure. For a given type of fiberglass, there is a limiting level of explosive action, at which the number of loads that do not lead to failure can be sufficiently large (more than ˜ 102). This level is attained under loads, which are an order of magnitude lower than the limiting loads under a single explosive action. Basalt plastic shells can be repeatedly used even at the loads, which cause deformation by ˜ 30-50% lower than the safe value ˜ 3.3.5% at single loading.

29 CFR 1915.116 - Use of gear.

Code of Federal Regulations, 2014 CFR

2014-07-01

..., shipbuilding and shipbreaking except that paragraphs (c) and (d) of this section shall apply to ship repairing and shipbuilding only. (b) Loads shall be safely rigged before being hoisted. (c) Plates shall be...

29 CFR 1915.116 - Use of gear.

Code of Federal Regulations, 2011 CFR

2011-07-01

..., shipbuilding and shipbreaking except that paragraphs (c) and (d) of this section shall apply to ship repairing and shipbuilding only. (b) Loads shall be safely rigged before being hoisted. (c) Plates shall be...

29 CFR 1915.116 - Use of gear.

Code of Federal Regulations, 2013 CFR

2013-07-01

..., shipbuilding and shipbreaking except that paragraphs (c) and (d) of this section shall apply to ship repairing and shipbuilding only. (b) Loads shall be safely rigged before being hoisted. (c) Plates shall be...

29 CFR 1915.116 - Use of gear.

Code of Federal Regulations, 2012 CFR

2012-07-01

..., shipbuilding and shipbreaking except that paragraphs (c) and (d) of this section shall apply to ship repairing and shipbuilding only. (b) Loads shall be safely rigged before being hoisted. (c) Plates shall be...

Research notes : listening to bridges.

DOT National Transportation Integrated Search

2008-09-01

The Federal Highway Administration requires owners of structurally deficient bridges to repair, replace, restrict truck loads, or conduct analysis and testing to maintain a safe highway system. Past experiments on reinforced concrete beams showed aco...

49 CFR 230.23 - Responsibility for general construction and safe working pressure.

Code of Federal Regulations, 2010 CFR

2010-10-01

... MAINTENANCE STANDARDS Boilers and Appurtenances § 230.23 Responsibility for general construction and safe... construction of the steam locomotive boilers under their control. The steam locomotive owner shall establish the safe working pressure for each steam locomotive boiler, after giving full consideration to the...

Lower bound buckling loads for design of laminate composite cylinders

NASA Astrophysics Data System (ADS)

Croll, James G. A.; Wang, Hongtao

2017-01-01

Over a period of more than 45 years, an extensive research program has allowed a series of very simple propositions, relating to the safe design of shells experiencing imperfection sensitive buckling, to be recast in the form of a series of lemmas. These are briefly summarized and their practical use is illustrated in relation to the prediction of safe lower bounds to the imperfection sensitive buckling of axially loaded, fiber reinforced polymeric, laminated cylinders. With a fundamental aspect of the approach, sometimes referred to as the reduced stiffness method, being the delineation of the various shell membrane and bending stiffness (or perhaps more appropriately energy) components contributing to the buckling resistance, the method will be shown to also provide a powerful way of making rational design decisions to optimize the use of fiber reinforcement.

Components of working memory and visual selective attention.

PubMed

Burnham, Bryan R; Sabia, Matthew; Langan, Catherine

2014-02-01

Load theory (Lavie, N., Hirst, A., De Fockert, J. W., & Viding, E. [2004]. Load theory of selective attention and cognitive control. Journal of Experimental Psychology: General, 133, 339-354.) proposes that control of attention depends on the amount and type of load that is imposed by current processing. Specifically, perceptual load should lead to efficient distractor rejection, whereas working memory load (dual-task coordination) should hinder distractor rejection. Studies support load theory's prediction that working memory load will lead to larger distractor effects; however, these studies used secondary tasks that required only verbal working memory and the central executive. The present study examined which other working memory components (visual, spatial, and phonological) influence visual selective attention. Subjects completed an attentional capture task alone (single-task) or while engaged in a working memory task (dual-task). Results showed that along with the central executive, visual and spatial working memory influenced selective attention, but phonological working memory did not. Specifically, attentional capture was larger when visual or spatial working memory was loaded, but phonological working memory load did not affect attentional capture. The results are consistent with load theory and suggest specific components of working memory influence visual selective attention. PsycINFO Database Record (c) 2014 APA, all rights reserved.

The safe home project.

PubMed

Arphorn, Sara; Jiraniratisai, Sopaphan; Rungtakul, Rungsri; Phutta, Nikom

2011-12-01

The Thai Health Promotion Foundation supported the Improvement of Quality of Life of Informal Workers project in Ban Luang District, Amphur Photaram, Ratchaburi Province. There were many informal workers in Ban Luang District. Sweet-crispy fish producers in Ban Luang were the largest group among the sweet-crispy fish producers in Thailand. This project was aimed at improving living and working conditions of informal workers, with a focus on the sweet-crispy fish group. Good practices of improved living and working conditions were used to help informal workers build safe, healthy and productive work environments. These informal workers often worked in substandard conditions and were exposed to various hazards in the working area. These hazards included risk of exposure to hot work environment, ergonomics-related injuries, chemical hazards, electrical hazards etc. Ergonomics problems were commonly in the sweet-crispy fish group. Unnatural postures such as prolonged sitting were performed dominantly. One hundred and fifty informal workers participated in this project. Occupational health volunteers were selected to encourage occupational health and safety in four groups of informal workers in 2009. The occupational health volunteers trained in 2008 were farmers, beauty salon workers and doll makers. The occupational health and safety knowledge is extended to a new informal worker group: sweet-crispy fish producer, in 2009. The occupational health and safety training for sweet-crispy fish group is conducted by occupational health volunteers. The occupational health volunteers increased their skills and knowledge assist in to make safe home and safe community through participatory oriented training. The improvement of living and working condition is conducted by using a modified WISH, Work Improvement for Safe Home, checklist. The plans of improvement were recorded. The informal workers showed improvement mostly on material handling and storage. The safe uses and safe storage of chemicals were introduced among farmers. The awareness of healthcare using personal protective equipments is increased in all groups especially in farmers. Safe home by local occupational health volunteer is proposed to be one effective measure for improvement of quality of life.

33 CFR 150.607 - What are the general safe working requirements?

Code of Federal Regulations, 2011 CFR

2011-07-01

... subchapter. (b) All machinery and equipment must be maintained in proper working order or removed. Personal Protective Equipment ... Workplace Conditions § 150.607 What are the general safe working requirements? (a) All equipment, including...

33 CFR 150.607 - What are the general safe working requirements?

Code of Federal Regulations, 2010 CFR

2010-07-01

... subchapter. (b) All machinery and equipment must be maintained in proper working order or removed. Personal Protective Equipment ... Workplace Conditions § 150.607 What are the general safe working requirements? (a) All equipment, including...

Degradable polyphosphoester-based silver-loaded nanoparticles as therapeutics for bacterial lung infections

NASA Astrophysics Data System (ADS)

Zhang, Fuwu; Smolen, Justin A.; Zhang, Shiyi; Li, Richen; Shah, Parth N.; Cho, Sangho; Wang, Hai; Raymond, Jeffery E.; Cannon, Carolyn L.; Wooley, Karen L.

2015-01-01

In this study, a new type of degradable polyphosphoester-based polymeric nanoparticle, capable of carrying silver cations via interactions with alkyne groups, has been developed as a potentially effective and safe treatment for lung infections. It was found that up to 15% (w/w) silver loading into the nanoparticles could be achieved, consuming most of the pendant alkyne groups along the backbone, as revealed by Raman spectroscopy. The well-defined Ag-loaded nanoparticles released silver in a controlled and sustained manner over 5 days, and displayed enhanced in vitro antibacterial activities against cystic fibrosis-associated pathogens and decreased cytotoxicity to human bronchial epithelial cells, in comparison to silver acetate.In this study, a new type of degradable polyphosphoester-based polymeric nanoparticle, capable of carrying silver cations via interactions with alkyne groups, has been developed as a potentially effective and safe treatment for lung infections. It was found that up to 15% (w/w) silver loading into the nanoparticles could be achieved, consuming most of the pendant alkyne groups along the backbone, as revealed by Raman spectroscopy. The well-defined Ag-loaded nanoparticles released silver in a controlled and sustained manner over 5 days, and displayed enhanced in vitro antibacterial activities against cystic fibrosis-associated pathogens and decreased cytotoxicity to human bronchial epithelial cells, in comparison to silver acetate. Electronic supplementary information (ESI) available: Materials, experimental details, and characterization. See DOI: 10.1039/c4nr07103d

Are Household Firearms Stored Less Safely in Homes With Adolescents?

PubMed Central

Johnson, Renee M.; Miller, Matthew; Vriniotis, Mary; Azrael, Deborah; Hemenway, David

2011-01-01

Objective To examine whether firearms are more frequently stored loaded, unlocked, or both in households with adolescents only (aged 13-17 years) compared with households with younger children only (aged 0-12 years). Design Random-digit-dial survey on firearms (n=2770). We computed bivariate associations between the presence of adolescents and firearm storage practices. Statistical significance was assessed using prevalence ratios with 95% confidence intervals. Setting United States. Participants Survey respondents with children (aged <18 years) who reported the presence of a household firearm. Main Outcome Measures Prevalence of firearms in the home stored loaded and/or unlocked. Results Of the 392 respondents, 22% had a loaded firearm, 32% had an unlocked firearm, and 8% had a firearm stored loaded and unlocked. Compared with households with younger children, households with adolescents only were somewhat more likely to store a firearm unlocked (42% vs 29%; prevalence ratio, 1.48; 95% confidence interval, 1.04-2.02), loaded (26% vs 20%; prevalence ratio, 1.25; 95% confidence interval, 0.82-1.91), or both (10% vs 8%; prevalence ratio, 1.43; 95% confidence interval, 0.64-3.19). Conclusions Parents of adolescents appear to be more likely to keep household firearms stored unsafely, especially with regard to keeping firearms unlocked. This is of concern because most youth firearm injuries happen to adolescents. Firearm injury prevention programs should directly target parents of adolescents to promote safe firearm storage. PMID:16894076

Probabilistic characterization of wind turbine blades via aeroelasticity and spinning finite element formulation

NASA Astrophysics Data System (ADS)

Velazquez, Antonio; Swartz, R. Andrew

2012-04-01

Wind energy is an increasingly important component of this nation's renewable energy portfolio, however safe and economical wind turbine operation is a critical need to ensure continued adoption. Safe operation of wind turbine structures requires not only information regarding their condition, but their operational environment. Given the difficulty inherent in SHM processes for wind turbines (damage detection, location, and characterization), some uncertainty in conditional assessment is expected. Furthermore, given the stochastic nature of the loading on turbine structures, a probabilistic framework is appropriate to characterize their risk of failure at a given time. Such information will be invaluable to turbine controllers, allowing them to operate the structures within acceptable risk profiles. This study explores the characterization of the turbine loading and response envelopes for critical failure modes of the turbine blade structures. A framework is presented to develop an analytical estimation of the loading environment (including loading effects) based on the dynamic behavior of the blades. This is influenced by behaviors including along and across-wind aero-elastic effects, wind shear gradient, tower shadow effects, and centrifugal stiffening effects. The proposed solution includes methods that are based on modal decomposition of the blades and require frequent updates to the estimated modal properties to account for the time-varying nature of the turbine and its environment. The estimated demand statistics are compared to a code-based resistance curve to determine a probabilistic estimate of the risk of blade failure given the loading environment.

The effects of load carriage on joint work at different running velocities.

PubMed

Liew, Bernard X W; Morris, Susan; Netto, Kevin

2016-10-03

Running with load carriage has become increasingly prevalent in sport, as well as many field-based occupations. However, the "sources" of mechanical work during load carriage running are not yet completely understood. The purpose of this study was to determine the influence of load magnitudes on the mechanical joint work during running, across different velocities. Thirty-one participants performed overground running at three load magnitudes (0%, 10%, 20% body weight), and at three velocities (3, 4, 5m/s). Three dimensional motion capture was performed, with synchronised force plate data captured. Inverse dynamics was used to quantify joint work in the stance phase of running. Joint work was normalized to a unit proportion of body weight and leg length (one dimensionless work unit=532.45J). Load significantly increased total joint work and total positive work and this effect was greater at faster velocities. Load carriage increased ankle positive work (β coefficient=rate of 6.95×10 -4 unit work per 1% BW carried), and knee positive (β=1.12×10 -3 unit) and negative work (β=-2.47×10 -4 unit), and hip negative work (β=-7.79×10 -4 unit). Load carriage reduced hip positive work and this effect was smaller at faster velocities. Inter-joint redistribution did not contribute significantly to altered mechanical work within the spectrum of load and velocity investigated. Hence, the ankle joint contributed to the greatest extent in work production, whilst that of the knee contributed to the greatest extent to work absorption when running with load. Copyright © 2016 Elsevier Ltd. All rights reserved.

Simplified Design Method for Tension Fasteners

NASA Astrophysics Data System (ADS)

Olmstead, Jim; Barker, Paul; Vandersluis, Jonathan

2012-07-01

Tension fastened joints design has traditionally been an iterative tradeoff between separation and strength requirements. This paper presents equations for the maximum external load that a fastened joint can support and the optimal preload to achieve this load. The equations, based on linear joint theory, account for separation and strength safety factors and variations in joint geometry, materials, preload, load-plane factor and thermal loading. The strength-normalized versions of the equations are applicable to any fastener and can be plotted to create a "Fastener Design Space", FDS. Any combination of preload and tension that falls within the FDS represents a safe joint design. The equation for the FDS apex represents the optimal preload and load capacity of a set of joints. The method can be used for preliminary design or to evaluate multiple pre-existing joints.

[A simulative biomechanical experiment on different position of none-cement acetabular components influencing the load distribution around acetabulum].

PubMed

Li, Dongsong; Liu, Jianguo; Li, Shuqiang; Fan, Honghui; Guan, Jikui

2008-02-01

In the present study, a three dimensional finite-element model of the human pelvic was reconstructed, and then, under different acetabular component position (the abduction angle ranges from 30 degrees to 70 degrees and the anteversion ranges from 5 degrees to 30degrees) the load distribution around the acetabular was evaluated by the computer biomechanical analysis program (Solidworks). Through the obtained load distribution results, the most even and reasonable range of the distribution was selected; therefore the safe range of the acetabular component implantation can be validated from the biomechanics aspect.

Accident resistant transport container

DOEpatents

Andersen, John A.; Cole, James K.

1980-01-01

The invention relates to a container for the safe air transport of plutonium having several intermediate wood layers and a load spreader intermediate an inner container and an outer shell for mitigation of shock during a hypothetical accident.

Accident resistant transport container

DOEpatents

Anderson, J.A.; Cole, K.K.

The invention relates to a container for the safe air transport of plutonium having several intermediate wood layers and a load spreader intermediate an inner container and an outer shell for mitigation of shock during a hypothetical accident.

30 CFR 77.1608 - Dumping facilities.

Code of Federal Regulations, 2011 CFR

2011-07-01

... weight of a loaded dump truck, trucks shall be dumped a safe distance back from the edge of the bank. (c... material. (d) Grizzlies, grates, and other sizing devices at dump and transfer points shall be anchored...

Flightworthy active control landing gear for a supersonic aircraft

NASA Technical Reports Server (NTRS)

Ross, I.

1980-01-01

A flightworthy active control landing gear system for a supersonic aircraft was designed to minimize aircraft loads during takeoff, impact, rollout, and taxi. The design consists of hydromechanical modifications to the existing gear and the development of a fail-safe electronic controller. analytical RESULTS INDICATE that for an aircraft sink rate of 0.914 m/sec (3 ft/sec) the system achieves a peak load reduction of 36% during landing impact.

Health and safety in clinical laboratories in developing countries: safety considerations.

PubMed

Ejilemele, A A; Ojule, A C

2004-01-01

Clinical laboratories are potentially hazardous work areas. Health and safety in clinical laboratories is becoming an increasingly important subject as a result of the emergence of highly infectious diseases such as hepatitis and HIV. This is even more so in developing countries where health and safety have traditionally been regarded as low priority issues, considering the more important health problems confronting the health authorities in these countries. We conducted a literature search using the medical subheadings titles on the INTERNET over a period of twenty years and summarized our findings. This article identifies hazards in the laboratories and highlights measures to make the laboratory a safer work place. It also emphasizes the mandatory obligations of employers and employees towards the attainment of acceptable safety standards in clinical laboratories in Third World countries in the face of the current HIV/AIDS epidemic in many of these developing countries especially in the sub-Saharan Africa while accommodating the increasing work load in these laboratories. Both the employer and the employee have major roles to play in the maintenance of a safe working environment. This can be achieved if measures discussed are incorporated into everyday laboratory practice.

Assessment of the Acceptability and Feasibility of Child Potties for Safe Child Feces Disposal in Rural Bangladesh.

PubMed

Hussain, Faruqe; Luby, Stephen P; Unicomb, Leanne; Leontsini, Elli; Naushin, Tania; Buckland, Audrey J; Winch, Peter J

2017-08-01

Indiscriminate defecation among young children and the unsafe disposal of their feces increases fecal contamination in the household environment and the risk of diarrheal disease transmission. Improved sanitary technology for children too young to use a latrine may facilitate safe feces disposal and reduce fecal contamination in the household environment. We assessed the acceptability and feasibility of child potties in rural Bangladesh in 2010. Our team introduced child potties into 26 households for 30 days, and conducted semistructured interviews, group discussions, and observations to assess the acceptability and feasibility of their use for parents and children. Residents of this rural Bangladeshi community accepted the child potties and caregivers found them to be a feasible means of managing child feces. The color, shape, design, and size of the potty influenced its acceptability and use. These residents reported that regular use of the potty improved the household's physical environment and caregiver and child personal hygiene. Regular potty use also reduced caregivers' work load by making feces collection and disposal easier. Primary caregivers viewed 4-6 months as the appropriate age to initiate potty training. Sanitation interventions should integrate and emphasize potties for children's feces management to reduce household environmental contamination.

Concurrent Working Memory Load Can Facilitate Selective Attention: Evidence for Specialized Load

ERIC Educational Resources Information Center

Park, Soojin; Kim, Min-Shik; Chun, Marvin M.

2007-01-01

Load theory predicts that concurrent working memory load impairs selective attention and increases distractor interference (N. Lavie, A. Hirst, J. W. de Fockert, & E. Viding, see record 2004-17825-003). Here, the authors present new evidence that the type of concurrent working memory load determines whether load impairs selective attention or not.…

Optimal robust control strategy of a solid oxide fuel cell system

NASA Astrophysics Data System (ADS)

Wu, Xiaojuan; Gao, Danhui

2018-01-01

Optimal control can ensure system safe operation with a high efficiency. However, only a few papers discuss optimal control strategies for solid oxide fuel cell (SOFC) systems. Moreover, the existed methods ignore the impact of parameter uncertainty on system instantaneous performance. In real SOFC systems, several parameters may vary with the variation of operation conditions and can not be identified exactly, such as load current. Therefore, a robust optimal control strategy is proposed, which involves three parts: a SOFC model with parameter uncertainty, a robust optimizer and robust controllers. During the model building process, boundaries of the uncertain parameter are extracted based on Monte Carlo algorithm. To achieve the maximum efficiency, a two-space particle swarm optimization approach is employed to obtain optimal operating points, which are used as the set points of the controllers. To ensure the SOFC safe operation, two feed-forward controllers and a higher-order robust sliding mode controller are presented to control fuel utilization ratio, air excess ratio and stack temperature afterwards. The results show the proposed optimal robust control method can maintain the SOFC system safe operation with a maximum efficiency under load and uncertainty variations.

Modeling Relevant to Safe Operations of U.S. Navy Vessels in Arctic Conditions: Physical Modeling of Ice Loads

DTIC Science & Technology

2016-06-01

zones with ice concentrations up to 40%. To achieve this goal, the Navy must determine safe operational speeds as a function of ice concen- tration...and full-scale experience with ice-capable hull forms that have shallow entry angles to promote flexural ice failure preferentially over crushing...plan view) of the proposed large-scale ice–hull impact experiment to be conducted in CRREL’s refrigerated towing basin. Shown here is a side-panel

Security Policies for Mitigating the Risk of Load Altering Attacks on Smart Grid Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ryutov, Tatyana; AlMajali, Anas; Neuman, Clifford

2015-04-01

While demand response programs implement energy efficiency and power quality objectives, they bring potential security threats to the Smart Grid. The ability to influence load in a system enables attackers to cause system failures and impacts the quality and integrity of power delivered to customers. This paper presents a security mechanism to monitor and control load according to a set of security policies during normal system operation. The mechanism monitors, detects, and responds to load altering attacks. We examined the security requirements of Smart Grid stakeholders and constructed a set of load control policies enforced by the mechanism. We implementedmore » a proof of concept prototype and tested it using the simulation environment. By enforcing the proposed policies in this prototype, the system is maintained in a safe state in the presence of load drop attacks.« less

Bioremediation of diesel from a rocky shoreline in an arid tropical climate.

PubMed

Guerin, Turlough F

2015-10-15

A non invasive sampling and remediation strategy was developed and implemented at shoreline contaminated with spilt diesel. To treat the contamination, in a practical, cost-effective, and safe manner (to personnel working on the stockpiles and their ship loading activity), a non-invasive sampling and remediation strategy was designed and implemented since the location and nature of the impacted geology (rock fill) and sediment, precluded conventional ex-situ and any in-situ treatment where drilling is required. A bioremediation process using surfactant, and added N & P and increased aeration, increased the degradation rate allowing the site owner to meet their regulatory obligations. Petroleum hydrocarbons decreased from saturation concentrations to less than detectable amounts at the completion of treatment. Copyright © 2015 Elsevier Ltd. All rights reserved.

Elastic, plastic, fracture analysis of masonry arches: A multi-span bridge case study

NASA Astrophysics Data System (ADS)

Lacidogna, Giuseppe; Accornero, Federico

2018-01-01

In this work a comparison is presented between elastic, plastic, and fracture analysis of the monumental arch bridge of Porta Napoli, Taranto (Italy). By means of a FEM model and applying the Mery's Method, the behavior of the curved structure under service loads is verified, while considering the Safe Theorem approach byHeyman, the ultimate carrying capacity of the structure is investigated. Moreover, by using Fracture Mechanics concepts, the damage process which takes place when the conditions assessed through linear elastic analysis are no longer valid, and before the set-in of the conditions established by means of the plastic limit analysis, is numerically analyzed. The study of these transitions returns an accurate and effective whole service life assessment of the Porta Napoli masonry arch bridge.

Safe Haven Laws and School Social Work

ERIC Educational Resources Information Center

Kopels, Sandra

2012-01-01

"Safe haven" laws are designed to protect infants from being killed or otherwise harmed. This article examines the safe haven laws from the states that comprise the Midwest School Social Work Council and the variations between these laws regarding the age of the infant, where the infant can be left, who is allowed to leave the infant, whether…

Effects of dynamic operating conditions on nitrification in biological rapid sand filters for drinking water treatment.

PubMed

Lee, Carson O; Boe-Hansen, Rasmus; Musovic, Sanin; Smets, Barth; Albrechtsen, Hans-Jørgen; Binning, Philip

2014-11-01

Biological rapid sand filters are often used to remove ammonium from groundwater for drinking water supply. They often operate under dynamic substrate and hydraulic loading conditions, which can lead to increased levels of ammonium and nitrite in the effluent. To determine the maximum nitrification rates and safe operating windows of rapid sand filters, a pilot scale rapid sand filter was used to test short-term increased ammonium loads, set by varying either influent ammonium concentrations or hydraulic loading rates. Ammonium and iron (flock) removal were consistent between the pilot and the full-scale filter. Nitrification rates and ammonia-oxidizing bacteria and archaea were quantified throughout the depth of the filter. The ammonium removal capacity of the filter was determined to be 3.4 g NH4-N m(-3) h(-1), which was 5 times greater than the average ammonium loading rate under reference operating conditions. The ammonium removal rate of the filter was determined by the ammonium loading rate, but was independent of both the flow and influent ammonium concentration individually. Ammonia-oxidizing bacteria and archaea were almost equally abundant in the filter. Both ammonium removal and ammonia-oxidizing bacteria density were strongly stratified, with the highest removal and ammonia-oxidizing bacteria densities at the top of the filter. Cell specific ammonium oxidation rates were on average 0.6 × 10(2) ± 0.2 × 10(2) fg NH4-N h(-1) cell(-1). Our findings indicate that these rapid sand filters can safely remove both nitrite and ammonium over a larger range of loading rates than previously assumed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Guided wave propagation in metallic and resin plates loaded with water on single surface

NASA Astrophysics Data System (ADS)

Hayashi, Takahiro; Inoue, Daisuke

2016-02-01

Our previous papers reported dispersion curves for leaky Lamb waves in a water-loaded plate and wave structures for several typical modes including quasi-Scholte waves [1,2]. The calculations were carried out with a semi-analytical finite element (SAFE) method developed for leaky Lamb waves. This study presents SAFE calculations for transient guided waves including time-domain waveforms and animations of wave propagation in metallic and resin water-loaded plates. The results show that non-dispersive and non-attenuated waves propagating along the interface between the fluid and the plate are expected for effective non-destructive evaluation of such fluid-loaded plates as storage tanks and transportation pipes. We calculated transient waves in both steel and polyvinyl chloride (PVC) plates loaded with water on a single side and input dynamic loading from a point source on the other water-free surface as typical examples of metallic and resin plates. For a steel plate, there exists a non-dispersive and non-attenuated mode, called the quasi-Scholte wave, having an almost identical phase velocity to that of water. The quasi-Scholte wave has superior generation efficiency in the low frequency range due to its broad energy distribution across the plate, whereas it is localized near the plate-water interface at higher frequencies. This means that it has superior detectability of inner defects. For a PVC plate, plural non-attenuated modes exist. One of the non-attenuated modes similar to the A0 mode of the Lamb wave in the form of a group velocity dispersion curve is promising for the non-destructive evaluation of the PVC plate because it provides prominent characteristics of generation efficiency and low dispersion.

Precise engineering of dapivirine-loaded nanoparticles for the development of anti-HIV vaginal microbicides.

PubMed

das Neves, José; Sarmento, Bruno

2015-05-01

Polymeric nanoparticles (NPs) have the potential to provide effective and safe delivery of antiretroviral drugs in the context of prophylactic anti-HIV vaginal microbicides. Dapivirine-loaded poly(d,l-lactic-co-glycolic acid) (PLGA) NPs were produced by an emulsion-solvent evaporation method, optimized for colloidal properties using a 3-factor, 3-level Box-Behnken experimental design, and characterized for drug loading, production yield, morphology, thermal behavior, drug release, in vitro cellular uptake, cytotoxicity and pro-inflammatory potential. Also, drug permeability/membrane retention in well-established HEC-1-A and CaSki cell monolayer models as mediated by NPs was assessed in the absence or presence of mucin. Box-Behnken design allowed optimizing monodisperse 170nm drug-loaded NPs. Drug release experiments showed an initial burst effect up to 4h, followed by sustained 24h release at pH 4.2 and 7.4. NPs were readily taken up by different genital and macrophage cell lines as assessed by fluorescence microscopy. Drug-loaded NPs presented lower or at least similar cytotoxicity as compared to the free drug, with up to around one-log increase in half-maximal cytotoxic concentration values. In all cases, no relevant changes in cell pro-inflammatory cytokine/chemokine production were observed. Dapivirine transport across cell monolayers was significantly decreased when mucin was present at the donor side with either NPs or the free drug, thus evidencing the influence of this natural glycoprotein in membrane permeability. Moreover, drug retention in cell monolayers was significantly higher for NPs in comparison with the free drug. Overall, obtained dapivirine-loaded PLGA NPs possess interesting technological and biological features that may contribute to their use as novel safe and effective vaginal microbicides. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Opposite effects of capacity load and resolution load on distractor processing.

PubMed

Zhang, Weiwei; Luck, Steven J

2015-02-01

According to the load theory of attention, an increased perceptual load reduces distractor processing whereas an increased working memory load facilitates distractor processing. Here we raise the possibility that the critical distinction may instead be between an emphasis on resolution and an emphasis on capacity. That is, perceptual load manipulations typically emphasize resolution (fine-grained discriminations), whereas working memory load manipulations typically emphasize capacity (simultaneous processing of multiple relevant stimuli). To test the plausibility of this hypothesis, we used a visual working memory task that emphasized either the number of items to be stored (capacity load, retaining 2 vs. 4 colors) or the precision of the representations (resolution load, detecting small vs. large color changes). We found that an increased capacity load led to increased flanker interference (a measure of distractor processing), whereas an increased resolution load led to reduced flanker interference. These opposite effects of capacity load and resolution load on distractor processing mirror the previously described opposite effects of perceptual load and working memory load.

Opposite Effects of Capacity Load and Resolution Load on Distractor Processing

PubMed Central

Zhang, Weiwei; Luck, Steven J.

2014-01-01

According to the load theory of attention, an increased perceptual load reduces distractor processing whereas an increased working memory load facilitates distractor processing. Here we raise the possibility that the critical distinction may instead be between an emphasis on resolution and an emphasis on capacity. That is, perceptual load manipulations typically emphasize resolution (fine-grained discriminations), whereas working memory load manipulations typically emphasize capacity (simultaneous processing of multiple relevant stimuli). To test the plausibility of this hypothesis, we used a visual working memory task that emphasized either the number of items to be stored (capacity load, retaining two versus four colors) or the precision of the representations (resolution load, detecting small versus large color changes). We found that an increased capacity load led to increased flanker interference (a measure of distractor processing), whereas an increased resolution load led to reduced flanker interference. These opposite effects of capacity load and resolution load on distractor processing mirror the previously described opposite effects of perceptual load and working memory load. PMID:25365573

7 CFR 1710.209 - Approval requirements for load forecast work plans.

Code of Federal Regulations, 2010 CFR

2010-01-01

... cooperate in the preparation of and submittal of the load forecast work plan of their power supply borrower. (b) An approved load forecast work plan establishes the process for the preparation and maintenance... approved load forecast work plan must outline the coordination and preparation requirements for both the...

Inductance and resistance measurement method for vessel detection and coil powering in all-surface inductive heating systems composed of outer squircle coils

NASA Astrophysics Data System (ADS)

Kilic, Veli Tayfun; Unal, Emre; Demir, Hilmi Volkan

2017-05-01

In this work, we investigate a method proposed for vessel detection and coil powering in an all-surface inductive heating system composed of outer squircle coils. Besides conventional circular coils, coils with different shapes such as outer squircle coils are used for and enable efficient all-surface inductive heating. Validity of the method, which relies on measuring inductance and resistance values of a loaded coil at different frequencies, is experimentally demonstrated for a coil with shape different from conventional circular coil. Simple setup was constructed with a small coil to model an all-surface inductive heating system. Inductance and resistance maps were generated by measuring coil's inductance and resistance values at different frequencies loaded by a plate made of different materials and located at various positions. Results show that in an induction hob for various coil geometries it is possible to detect a vessel's presence, to identify its material type and to specify its position on the hob surface by considering inductance and resistance of the coil measured on at least two different frequencies. The studied method is important in terms of enabling safe, efficient and user flexible heating in an all-surface inductive heating system by automatically detecting the vessel's presence and powering on only the coils that are loaded by the vessel with predetermined current levels.

Dynamic Modeling, Model-Based Control, and Optimization of Solid Oxide Fuel Cells

NASA Astrophysics Data System (ADS)

Spivey, Benjamin James

2011-07-01

Solid oxide fuel cells are a promising option for distributed stationary power generation that offers efficiencies ranging from 50% in stand-alone applications to greater than 80% in cogeneration. To advance SOFC technology for widespread market penetration, the SOFC should demonstrate improved cell lifetime and load-following capability. This work seeks to improve lifetime through dynamic analysis of critical lifetime variables and advanced control algorithms that permit load-following while remaining in a safe operating zone based on stress analysis. Control algorithms typically have addressed SOFC lifetime operability objectives using unconstrained, single-input-single-output control algorithms that minimize thermal transients. Existing SOFC controls research has not considered maximum radial thermal gradients or limits on absolute temperatures in the SOFC. In particular, as stress analysis demonstrates, the minimum cell temperature is the primary thermal stress driver in tubular SOFCs. This dissertation presents a dynamic, quasi-two-dimensional model for a high-temperature tubular SOFC combined with ejector and prereformer models. The model captures dynamics of critical thermal stress drivers and is used as the physical plant for closed-loop control simulations. A constrained, MIMO model predictive control algorithm is developed and applied to control the SOFC. Closed-loop control simulation results demonstrate effective load-following, constraint satisfaction for critical lifetime variables, and disturbance rejection. Nonlinear programming is applied to find the optimal SOFC size and steady-state operating conditions to minimize total system costs.

77 FR 31647 - Establishing Indicators to Determine Whether State Plan Operations are At Least as Effective as...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-29

... their information and participate through a single representative. Members of the general public may... working man and woman in the Nation safe and healthful working conditions * * *.'' The Act also encourages.... OSHA's mission is ``to assure safe and healthful working conditions for working men and women by...

Multilevel models in the explanation of the relationship between safety climate and safe behavior.

PubMed

Cheyne, Alistair; Tomás, José M; Oliver, Amparo

2013-01-01

This study examines the relationships between components of organizational safety climate, including employee attitudes to organizational safety issues; perceptions of the physical working environment, and evaluations of worker engagement with safety issues; and relates these to self-reported levels of safety behavior. It attempts to explore the relationships between these variables in 1189 workers across 78 work groups in a large transportation organization. Evaluations of safety climate, the working environment and worker engagement, as well as safe behaviors, were collected using a self report questionnaire. The multilevel analysis showed that both levels of evaluation (the work group and the individual), and some cross-level interactions, were significant in explaining safe behaviors. Analyses revealed that a number of variables, at both levels, were associated with worker engagement and safe behaviors. The results suggest that, while individual evaluations of safety issues are important, there is also a role for the fostering of collective safety climates in encouraging safe behaviors and therefore reducing accidents.

The study of mechanical behavior on the interface between calcar-defect femur and restorations by means of finite element analysis

NASA Astrophysics Data System (ADS)

Shi, X. H.; Jiang, W.; Chen, H. Z.; Zou, W.; Wang, W. D.; Guo, Z.; Luo, J. M.; Gu, Z. W.; Zhang, X. D.

2008-11-01

The mechanical behaviors of calcar-defected femur and restorations under physiological load are the key factors that will greatly influence the success of femur calcar defect repairing, especially the stress distribution on the bone-restoration interface. 3D finite elements analysis (FEA) was used to analyze the mechanical characters on the interfaces between femoral calcar defects and bone cement or HA restorations. Under the load of two times of a human weight (1436.03 N) and with the increase of the defect dimension from 6 mm to 12 mm, the maximal stresses on the surface of restorations are from 7.06 MPa to 11.89 MPa for bone cement and 2.97-9 MPa for HA separately. In this condition, HA restoration will probably be broken on the bone-restoration interface when the defect diameter is beyond 8 mm. Furthermore, under the load of 1.5 times of a human weight, HA restoration would not be safe unless the defect dimension is smaller than 10 mm, because the maximal stress (4.62 MPa) on the restoration is only a little lower than compressive strength of HA, otherwise the bone fixation device should be applied to ensure the safety. It is relatively safe for all restorations under all the tested defect sizes when the load is just the weight of a human body.

Analysis of Bearing Capacity Pile Foundation with Using Capwap Software for Testing Pile Driving Analyzer (pda) at Fasfel Development Project Parlimbungan Ketek Sikara-Kara Mandailing Natal District (north Sumatera)

NASA Astrophysics Data System (ADS)

Oberlyn Simanjuntak, Johan; Suita, Diana

2017-12-01

Pile foundation is one type deep foundation that serves to distribute the load of hard soil structure loading which has a high bearing capacity that is located deep enough inside the soil. To determine the bearing capacity of the pile and at the same time control the Calendring results, the Pile Driving Analyzer (PDA) test at 8 pile sections from the 84 point piling section (10% of the number sections), the results were analyzed by CAPWAP SOFTWARE, and the highest bearing capacity of Ru 177 ton and the lowest bearing capacity of 111 tons, is bigger than the plan load which load plans that is 60,9 tons. Finally the PDA safe is bearing bearing capacity of the load planning.

Preparation and evaluation of icariside II-loaded binary mixed micelles using Solutol HS15 and Pluronic F127 as carriers.

PubMed

Hou, Jian; Wang, Jing; Sun, E; Yang, Lei; Yan, Hong-Mei; Jia, Xiao-Bin; Zhang, Zhen-Hai

2016-11-01

An effective anti-cancer drug, icariside II (IS), has been used to treat a variety of cancers in vitro. However, its poor aqueous solubility and permeability lead to low oral bioavailability. The aim of this work was to use Solutol®HS15 and Pluronic F127 as surfactants to develop novel mixed micelles to enhance the oral bioavailability of IS by improving permeability and inhibiting efflux. The IS-loaded mixed micelles were prepared using the method of ethanol thin-film hydration. The physicochemical properties, dissolution property, oral bioavailability of the male SD rats, permeability and efflux of Caco-2 transport models, and gastrointestinal safety of the mixed micelles were evaluated. The optimized IS-loaded mixed micelles showed that at 4:1 ratio of Solutol®HS15 and Pluronic F127, the particle size was 12.88 nm with an acceptable polydispersity index of 0.172. Entrapment efficiency (94.6%) and drug loading (9.7%) contributed to the high solubility (11.7 mg/mL in water) of IS, which increased about 900-fold. The SF-IS mixed micelle release profile showed a better sustained release property than that of IS. In Caco-2 cell monolayer models, the efflux ratio dramatically decreased by 83.5%, and the relative bioavailability of the mixed micelles (AUC 0-∞ ) compared with that of IS (AUC 0-∞ ) was 317%, indicating potential for clinical application. In addition, a gastrointestinal safety assay also provided reliable clinical evidence for the safe use of this micelle.

MSC/NASTRAN Stress Analysis of Complete Models Subjected to Random and Quasi-Static Loads

NASA Technical Reports Server (NTRS)

Hampton, Roy W.

2000-01-01

Space payloads, such as those which fly on the Space Shuttle in Spacelab, are designed to withstand dynamic loads which consist of combined acoustic random loads and quasi-static acceleration loads. Methods for computing the payload stresses due to these loads are well known and appear in texts and NASA documents, but typically involve approximations such as the Miles' equation, as well as possible adjustments based on "modal participation factors." Alternatively, an existing capability in MSC/NASTRAN may be used to output exact root mean square [rms] stresses due to the random loads for any specified elements in the Finite Element Model. However, it is time consuming to use this methodology to obtain the rms stresses for the complete structural model and then combine them with the quasi-static loading induced stresses. Special processing was developed as described here to perform the stress analysis of all elements in the model using existing MSC/NASTRAN and MSC/PATRAN and UNIX utilities. Fail-safe and buckling analyses applications are also described.

Effects of working memory contents and perceptual load on distractor processing: When a response-related distractor is held in working memory.

PubMed

Koshino, Hideya

2017-01-01

Working memory and attention are closely related. Recent research has shown that working memory can be viewed as internally directed attention. Working memory can affect attention in at least two ways. One is the effect of working memory load on attention, and the other is the effect of working memory contents on attention. In the present study, an interaction between working memory contents and perceptual load in distractor processing was investigated. Participants performed a perceptual load task in a standard form in one condition (Single task). In the other condition, a response-related distractor was maintained in working memory, rather than presented in the same stimulus display as a target (Dual task). For the Dual task condition, a significant compatibility effect was found under high perceptual load; however, there was no compatibility effect under low perceptual load. These results suggest that the way the contents of working memory affect visual search depends on perceptual load. Copyright © 2016 Elsevier B.V. All rights reserved.

Research notes : monitoring the health of bridges.

DOT National Transportation Integrated Search

2006-02-01

Research at Oregon State University has provided ODOT with better analytical tools for determining the safe load capacity of the cracked bridges. ODOT personnel now know that cracks alone do not necessarily mean that a bridge must be replaced. Method...

30 CFR 77.1304 - Blasting agents; special provisions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... connection with pneumatic loading machines shall be of the semiconductive type, having a total resistance low... electric currents to a safe level. Wire-countered hose shall not be used because of the potential hazard from stray electric currents. ...

30 CFR 77.1304 - Blasting agents; special provisions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... connection with pneumatic loading machines shall be of the semiconductive type, having a total resistance low... electric currents to a safe level. Wire-countered hose shall not be used because of the potential hazard from stray electric currents. ...

Lead Poisoning Prevention Tips

MedlinePlus

... be done to prevent exposure to lead? Lead-Safe Work Coloring book Reduce a child’s exposure from non- ... here to print a coloring storybook on lead-safe work [PDF - 1.94 MB] . Top of Page To ...

Isolating Age-Group Differences in Working Memory Load-Related Neural Activity: Assessing the Contribution of Working Memory Capacity Using a Partial-Trial fMRI Method

PubMed Central

Bennett, Ilana J.; Rivera, Hannah G.; Rypma, Bart

2013-01-01

Previous studies examining age-group differences in working memory load-related neural activity have yielded mixed results. When present, age-group differences in working memory capacity are frequently proposed to underlie these neural effects. However, direct relationships between working memory capacity and working memory load-related activity have only been observed in younger adults. These relationships remain untested in healthy aging. Therefore, the present study examined patterns of working memory load-related activity in 22 younger and 20 older adults and assessed the contribution of working memory capacity to these load-related effects. Participants performed a partial-trial delayed response item recognition task during functional magnetic resonance imaging. In this task, participants encoded either 2 or 6 letters, maintained them during a delay, and then indicated whether a probe was present in the memory set. Behavioral results revealed faster and more accurate responses to load 2 versus 6, with age-group differences in this load condition effect for the accuracy measure. Neuroimaging results revealed one region (medial superior frontal gyrus) that showed age-group differences in load-related activity during the retrieval period, with less (greater) neural activity for the low versus high load condition in younger (older) adults. Furthermore, for older adults, load-related activity did not vary as a function of working memory capacity. Thus, working memory-related activity varies with healthy aging, but these patterns are not due solely to working memory capacity. Neurocognitive aging theories that feature capacity will need to account for these results. PMID:23357076

Pumped storage system model and experimental investigations on S-induced issues during transients

NASA Astrophysics Data System (ADS)

Zeng, Wei; Yang, Jiandong; Hu, Jinhong

2017-06-01

Because of the important role of pumped storage stations in the peak regulation and frequency control of a power grid, pump turbines must rapidly switch between different operating modes, such as fast startup and load rejection. However, pump turbines go through the unstable S region in these transition processes, threatening the security and stability of the pumped storage station. This issue has mainly been investigated through numerical simulations, while field experiments generally involve high risks and are difficult to perform. Therefore, in this work, the model test method was employed to study S-induced security and stability issues for a pumped storage station in transition processes. First, a pumped storage system model was set up, including the piping system, model units, electrical control systems and measurement system. In this model, two pump turbines with different S-shaped characteristics were installed to determine the influence of S-shaped characteristics on transition processes. The model platform can be applied to simulate any hydraulic transition process that occurs in real power stations, such as load rejection, startup, and grid connection. On the experimental platform, the S-shaped characteristic curves were measured to be the basis of other experiments. Runaway experiments were performed to verify the impact of the S-shaped characteristics on the pump turbine runaway stability. Full load rejection tests were performed to validate the effect of the S-shaped characteristics on the water-hammer pressure. The condition of one pump turbine rejecting its load after another defined as one-after-another (OAA) load rejection was performed to validate the possibility of S-induced extreme draft tube pressure. Load rejection experiments with different guide vane closing schemes were performed to determine a suitable scheme to adapt the S-shaped characteristics. Through these experiments, the threats existing in the station were verified, the appropriate measures were summarized, and an important experimental basis for the safe and stable operation of a pumped storage station was provided.

Edward W. Jennings | NREL

Science.gov Websites

practices promoting a safe and supportive working environment. His research interests include environmental, safety, and health (ESH) and facility issues, he is responsible for implementing safe work plan; working directly with awardees by performing on-site validations to collect and analyze enzyme

Careers | NREL

Science.gov Websites

lab. Discover New Opportunities Find a Job Our Culture Within our safe and supportive work environment Simulation and Optimization Researcher Our Culture Within our safe and supportive work environment, we NRELians what they enjoy most about working at the lab, many will say, "the people." Meet an

Investigation of structural factors of safety for the space shuttle

NASA Technical Reports Server (NTRS)

1972-01-01

A study was made of the factors governing the structural design of the fully reusable space shuttle booster to establish a rational approach to select optimum structural factors of safety. The study included trade studies of structural factors of safety versus booster service life, weight, cost, and reliability. Similar trade studies can be made on other vehicles using the procedures developed. The major structural components of a selected baseline booster were studied in depth, each being examined to determine the fatigue life, safe-life, and fail-safe capabilities of the baseline design. Each component was further examined to determine its reliability and safety requirements, and the change of structural weight with factors of safety. The apparent factors of safety resulting from fatigue, safe-life, proof test, and fail-safe requirements were identified. The feasibility of reduced factors of safety for design loads such as engine thrust, which are well defined, was examined.

Safe Landing Strategies During a Fall: Systematic Review and Meta-Analysis.

PubMed

Moon, Yaejin; Sosnoff, Jacob J

2017-04-01

To systematically synthesize information on safe landing strategies for a fall, and quantitatively examine the effects of the strategies to reduce the risk of injury from a fall. PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature, and Cochrane Library. Databases were searched using the combinations of keywords of "falls," "strategy," "impact," and "load." Randomized controlled trials, cohort studies, pre-post studies, and cross-sectional studies were included. Fall strategies were extracted and categorized by falling direction. Measurements of impact loads that reflect the risk of injuries were extracted (eg, impact velocity, impact force, fall duration, impact angle). Hedges' g was used as effect size to quantify the effect of a protective landing strategy to reduce the impact load. A total of 7 landing strategies (squatting, elbow flexion, forward rotation, martial arts rolling, martial arts slapping, relaxed muscle, stepping) in 13 studies were examined. In general, all strategies, except for the martial arts slapping technique, significantly reduced impact load (g values=.73-2.70). Squatting was an efficient strategy to reduce impact in backward falling (g=1.77), while elbow flexion with outstretched arms was effective in forward falling (g=.82). Also, in sideways falling strategies, martial arts rolling (g=2.70) and forward rotation (g=.82) were the most efficient strategies to reduce impact load. The results showed that landing strategies have a significant effect on reducing impact load during a fall and might be effective to reduce the impact load of falling. The current study also highlighted limitations of the previous studies that focused on a young population and self-initiated falls. Further investigation with elderly individuals and unexpected falls is necessary to verify the effectiveness and suitability of the strategies for at-risk populations in real-life falls. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Intelligent Load Manager (LOADMAN): Application of Expert System Technology to Load Management Problems in Power Generation and Distribution Systems

DTIC Science & Technology

1988-08-10

addrsesed to it, the wall-receptacle module energizes a relay. Modules can be built to use a triac instead and have the capacity to increase or decrease... modulated by other constraints for a safe, functional ana effective power distribution system. 2.2.3 BackuR Equipment Alternate power sources are...environments have limited sensor capability and no remote control capability. However, future enhancements to current equipment, such as frequency- modulated

Experiments with Geometric Non-Linear Coupling for Analytical Validation

DTIC Science & Technology

2010-03-01

maintaining a high safety factor. This is the primary constraint and is very important in keeping the end conditions of the experiment known. 3.1.4...the maximum load case while maintaining a safety factor of at least 2. Figure 3.14: Cable and Winch. The load is measured using a 3,000 lbf...the class and power of this laser, laser eyewear is required for safe use of the system. The Photon 80 can scan at various levels of detail. For

30 CFR 77.1604 - Transportation of persons; overcrowding.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Transportation of persons; overcrowding. 77... UNDERGROUND COAL MINES Loading and Haulage § 77.1604 Transportation of persons; overcrowding. (a) No man-trip... are specifically designed to make such transportation safe. ...

77 FR 33481 - Information Collection Activities: Subpart A, General; Submitted for Office of Management and...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-06

... to assure that uniform methods are employed by lessees for load testing of cranes. Review welding plans, procedures, and records to ensure that welding is conducted in a safe and workmanlike manner by...

30 CFR 77.1604 - Transportation of persons; overcrowding.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Transportation of persons; overcrowding. 77... UNDERGROUND COAL MINES Loading and Haulage § 77.1604 Transportation of persons; overcrowding. (a) No man-trip... are specifically designed to make such transportation safe. ...

30 CFR 77.1604 - Transportation of persons; overcrowding.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Transportation of persons; overcrowding. 77... UNDERGROUND COAL MINES Loading and Haulage § 77.1604 Transportation of persons; overcrowding. (a) No man-trip... are specifically designed to make such transportation safe. ...

30 CFR 77.1604 - Transportation of persons; overcrowding.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Transportation of persons; overcrowding. 77... UNDERGROUND COAL MINES Loading and Haulage § 77.1604 Transportation of persons; overcrowding. (a) No man-trip... are specifically designed to make such transportation safe. ...

30 CFR 77.1604 - Transportation of persons; overcrowding.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Transportation of persons; overcrowding. 77... UNDERGROUND COAL MINES Loading and Haulage § 77.1604 Transportation of persons; overcrowding. (a) No man-trip... are specifically designed to make such transportation safe. ...

Using building information modeling to track and assess the structural condition of bridges.

DOT National Transportation Integrated Search

2016-08-01

National Bridge Inspection Standards do not require documenting damage locations during an inspection, but bridge evaluation provisions highlight the importance of it. When determining a safe load-carrying capacity of a bridge, damage location inform...

Effects of Wheel-Load Spatial Repeatability on Road Damage : A Literature Review

DOT National Transportation Integrated Search

1998-09-01

Concerns about growing governmental budgetary deficits and the awareness of the economic advantages associated with a safe and well-maintained road infrastructure are two of the main reasons for devoting attention to better understanding the problem ...

No matter how large or how small, oilwell servicing firms work safely

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lyle, D.

1995-07-01

In working safely, the size of the company doesn`t matter as much as the dedication of the people in maintaining a safe workplace. Poe Servicing Inc. of Oberlin, Kan., earned the 1994 Association of Oilwell Servicing Contractors (AOSC) gold safety award for smaller companies that put in 10,000 to 50,000 man-hours of work. AOSC`s group one. The employees watch out for each other, and they use common sense. The common sense part of the program means the company knows new people are most susceptible to accidents, so they send them out to observe before putting them to work.

Air-to-Water Heat Pumps With Radiant Delivery in Low-Load Homes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Backman, C.; German, A.; Dakin, B.

2013-12-01

Space conditioning represents nearly 50% of average residential household energy consumption, highlighting the need to identify alternative cost-effective, energy-efficient cooling and heating strategies. As homes are better built, there is an increasing need for strategies that are particularly well suited for high performance, low load homes. ARBI researchers worked with two test homes in hot-dry climates to evaluate the in-situ performance of air-to-water heat pump (AWHP) systems, an energy efficient space conditioning solution designed to cost-effectively provide comfort in homes with efficient, safe, and durable operation. Two monitoring projects of test houses in hot-dry climates were initiated in 2010 tomore » test this system. Both systems were fully instrumented and have been monitored over one year to capture complete performance data over the cooling and heating seasons. Results are used to quantify energy savings, cost-effectiveness, and system performance using different operating modes and strategies. A calibrated TRNSYS model was developed and used to evaluate performance in various climate regions. This strategy is most effective in tight, insulated homes with high levels of thermal mass (i.e. exposed slab floors).« less

Preclinical Development and In Vivo Efficacy of Ceftiofur-PLGA Microparticles

PubMed Central

Vilos, Cristian; Velasquez, Luis A.; Rodas, Paula I.; Zepeda, Katherine; Bong, Soung-Jae; Herrera, Natalia; Cantin, Mario; Simon, Felipe; Constandil, Luis

2015-01-01

Drug delivery systems based on polymeric microparticles represent an interesting field of development for the treatment of several infectious diseases for humans and animals. In this work, we developed PLGA microparticles loaded with ceftiofur (PLGA-cef), a third- generation cephalosporin that is used exclusively used in animals. PLGA-cef was prepared by the double emulsion w/o/w method, and exhibited a diameter in the range of 1.5–2.2 μm, and a negative ζ potential in the range of -35 to -55 mV. The loading yield of PLGA-cef was ~7% and encapsulation efficiency was approximately 40%. The pharmacokinetic study demonstrated a sustained release profile of ceftiofur for 20 days. PLGA-cef administrated in a single dose was more effective than ceftiofur non-encapsulated in rats challenged with S. Typhimurium. The in vivo toxicological evaluation showed that PLGA-cef did not affect the blood biochemical, hematological and hemostasis parameters. Overall, the PLGA-cef showed slow in vivo release profile, high antibacterial efficacy, and low toxicity. The results obtained supports the safe application of PLGA-cef as sustained release platform in the veterinary industry. PMID:25915043

Electrocortical and ocular indices of attention to fearful and neutral faces presented under high and low working memory load.

PubMed

MacNamara, Annmarie; Schmidt, Joseph; Zelinsky, Gregory J; Hajcak, Greg

2012-12-01

Working memory load reduces the late positive potential (LPP), consistent with the notion that functional activation of the DLPFC attenuates neural indices of sustained attention. Visual attention also modulates the LPP. In the present study, we sought to determine whether working memory load might exert its influence on ERPs by reducing fixations to arousing picture regions. We simultaneously recorded eye-tracking and EEG while participants performed a working memory task interspersed with the presentation of task-irrelevant fearful and neutral faces. As expected, fearful compared to neutral faces elicited larger N170 and LPP amplitudes; in addition, working memory load reduced the N170 and the LPP. Participants made more fixations to arousing regions of neutral faces and faces presented under high working memory load. Therefore, working memory load did not induce avoidance of arousing picture regions and visual attention cannot explain load effects on the N170 and LPP. Copyright © 2012 Elsevier B.V. All rights reserved.

Randomised, double blind trial of two loading dose regimens of diamorphine in ventilated newborn infants.

PubMed

Barker, D P; Simpson, J; Pawula, M; Barrett, D A; Shaw, P N; Rutter, N

1995-07-01

To compare the safety and efficacy of two loading doses of diamorphine in 27 ventilated newborn infants in a randomised double blind trial. Fifty or 200 mcg/kg were infused intravenously over 30 minutes, followed by a 15 mcg/kg/hour continuous infusion. Serial measurements were made of physiology, behaviour, and stress hormones. Both loading doses produced small but significant falls in blood pressure. The 200 mcg/kg dose produced greater respiratory depression, and two infants deteriorated clinically, requiring resuscitation. Loading reduced respiratory effort in most of the infants, but had little effect on behavioural activity. Stress hormone concentrations were reduced at six hours in both dosage groups; differences between loading doses were not significant. Morphine, morphine-3-glucuronide, and morphine-6-glucuronide were detected in the plasma of all patients. No significant differences in concentrations between loading doses were found. Diamorphine reduces the stress response in ventilated newborn infants. A high loading dose confers no benefit, and may produce undesirable physiological effects. A 50 mcg/kg loading dose seems to be safe and effective.

Randomised, double blind trial of two loading dose regimens of diamorphine in ventilated newborn infants.

PubMed Central

Barker, D. P.; Simpson, J.; Pawula, M.; Barrett, D. A.; Shaw, P. N.; Rutter, N.

1995-01-01

AIMS--To compare the safety and efficacy of two loading doses of diamorphine in 27 ventilated newborn infants in a randomised double blind trial. METHODS--Fifty or 200 mcg/kg were infused intravenously over 30 minutes, followed by a 15 mcg/kg/hour continuous infusion. Serial measurements were made of physiology, behaviour, and stress hormones. RESULTS--Both loading doses produced small but significant falls in blood pressure. The 200 mcg/kg dose produced greater respiratory depression, and two infants deteriorated clinically, requiring resuscitation. Loading reduced respiratory effort in most of the infants, but had little effect on behavioural activity. Stress hormone concentrations were reduced at six hours in both dosage groups; differences between loading doses were not significant. Morphine, morphine-3-glucuronide, and morphine-6-glucuronide were detected in the plasma of all patients. No significant differences in concentrations between loading doses were found. CONCLUSIONS--Diamorphine reduces the stress response in ventilated newborn infants. A high loading dose confers no benefit, and may produce undesirable physiological effects. A 50 mcg/kg loading dose seems to be safe and effective. PMID:7552591

Transient/structural analysis of a combustor under explosive loads

NASA Technical Reports Server (NTRS)

Gregory, Peyton B.; Holland, Anne D.

1992-01-01

The 8-Foot High Temperature Tunnel (HTT) at NASA Langley Research Center is a combustion-driven blow-down wind tunnel. A major potential failure mode that was considered during the combustor redesign was the possibility of a deflagration and/or detonation in the combustor. If a main burner flame-out were to occur, then unburned fuel gases could accumulate and, if reignited, an explosion could occur. An analysis has been performed to determine the safe operating limits of the combustor under transient explosive loads. The failure criteria was defined and the failure mechanisms were determined for both peak pressures and differential pressure loadings. An overview of the gas dynamics analysis was given. A finite element model was constructed to evaluate 13 transient load cases. The sensitivity of the structure to the frequency content of the transient loading was assessed. In addition, two closed form dynamic analyses were conducted to verify the finite element analysis. It was determined that the differential pressure load or thrust load was the critical load mechanism and that the nozzle is the weak link in the combustor system.

Isolating age-group differences in working memory load-related neural activity: assessing the contribution of working memory capacity using a partial-trial fMRI method.

PubMed

Bennett, Ilana J; Rivera, Hannah G; Rypma, Bart

2013-05-15

Previous studies examining age-group differences in working memory load-related neural activity have yielded mixed results. When present, age-group differences in working memory capacity are frequently proposed to underlie these neural effects. However, direct relationships between working memory capacity and working memory load-related activity have only been observed in younger adults. These relationships remain untested in healthy aging. Therefore, the present study examined patterns of working memory load-related activity in 22 younger and 20 older adults and assessed the contribution of working memory capacity to these load-related effects. Participants performed a partial-trial delayed response item recognition task during functional magnetic resonance imaging. In this task, participants encoded either 2 or 6 letters, maintained them during a delay, and then indicated whether a probe was present in the memory set. Behavioral results revealed faster and more accurate responses to load 2 versus 6, with age-group differences in this load condition effect for the accuracy measure. Neuroimaging results revealed one region (medial superior frontal gyrus) that showed age-group differences in load-related activity during the retrieval period, with less (greater) neural activity for the low versus high load condition in younger (older) adults. Furthermore, for older adults, load-related activity did not vary as a function of working memory capacity. Thus, working memory-related activity varies with healthy aging, but these patterns are not due solely to working memory capacity. Neurocognitive aging theories that feature capacity will need to account for these results. Copyright © 2013 Elsevier Inc. All rights reserved.

Protect Your Family from Lead in Your Home

MedlinePlus

... to Renovate Right, to learn about the lead-safe work practices that contractors are required to follow when ... lead-based paint is present and use lead-safe work practices There are state and federal programs in ...

33 CFR 150.607 - What are the general safe working requirements?

Code of Federal Regulations, 2012 CFR

2012-07-01

... machinery, cranes, derricks, portable power tools, and, most importantly, safety gear must be used in a safe... subchapter. (b) All machinery and equipment must be maintained in proper working order or removed. Personal...

33 CFR 150.607 - What are the general safe working requirements?

Code of Federal Regulations, 2013 CFR

2013-07-01

... machinery, cranes, derricks, portable power tools, and, most importantly, safety gear must be used in a safe... subchapter. (b) All machinery and equipment must be maintained in proper working order or removed. Personal...

33 CFR 150.607 - What are the general safe working requirements?

Code of Federal Regulations, 2014 CFR

2014-07-01

... machinery, cranes, derricks, portable power tools, and, most importantly, safety gear must be used in a safe... subchapter. (b) All machinery and equipment must be maintained in proper working order or removed. Personal...

The Load-Bearing Capacity of Timber-Glass Composite I-Beams Made with Polyurethane Adhesives

NASA Astrophysics Data System (ADS)

Rodacki, Konrad

2017-12-01

This article discusses the issue of composite timber-glass I-beams, which are an interesting alternative for load-bearing beams of ceilings and roofs. The reasoning behind the use of timber-glass I-beams is the combination of the best features of both materials - this enables the creation of particularly safe beams with regard to structural stability and post-breakage load capacity. Due to the significant differences between the bonding surfaces of timber and glass, a study on the adhesion of various adhesives to both surfaces is presented at the beginning of the paper. After examination, two adhesives were selected for offering the best performance when used with composite beams. The beams were investigated using a four-point bending test under quasi-static loading.

Endocytotic potential governs magnetic particle loading in dividing neural cells: studying modes of particle inheritance

PubMed Central

Tickle, Jacqueline A; Jenkins, Stuart I; Polyak, Boris; Pickard, Mark R; Chari, Divya M

2016-01-01

Aim: To achieve high and sustained magnetic particle loading in a proliferative and endocytotically active neural transplant population (astrocytes) through tailored magnetite content in polymeric iron oxide particles. Materials & methods: MPs of varying magnetite content were applied to primary-derived rat cortical astrocytes ± static/oscillating magnetic fields to assess labeling efficiency and safety. Results: Higher magnetite content particles display high but safe accumulation in astrocytes, with longer-term label retention versus lower/no magnetite content particles. Magnetic fields enhanced loading extent. Dynamic live cell imaging of dividing labeled astrocytes demonstrated that particle distribution into daughter cells is predominantly ‘asymmetric’. Conclusion: These findings could inform protocols to achieve efficient MP loading into neural transplant cells, with significant implications for post-transplantation tracking/localization. PMID:26785794

Wake-Induced Aerodynamics on a Trailing Aircraft

NASA Technical Reports Server (NTRS)

Mendenhall, Michael R.; Lesieutre, Daniel J.; Kelly, Michael J.

2016-01-01

NASA conducted flight tests to measure the exhaust products from alternative fuels using a DC-8 transport aircraft and a Falcon business jet. An independent analysis of the maximum vortex-induced loads on the Falcon in the DC-8 wake was conducted for pre-flight safety analysis and to define safe trail distances for the flight tests. Static and dynamic vortex-induced aerodynamic loads on the Falcon were predicted at a matrix of locations aft of the DC-8 under flight-test conditions, and the maximum loads were compared with design limit loads to assess aircraft safety. Trajectory simulations for the Falcon during close encounters with the DC-8 wake were made to study the vortex-induced loads during traverses of the DC-8 primary trailing vortex. A parametric study of flight traverses through the trailing vortex was conducted to assess Falcon flight behavior and motion characteristics.

Full Body Loading for Small Exercise Devices Project

NASA Technical Reports Server (NTRS)

Downs, Meghan; Hanson, Andrea; Newby, Nathaniel

2015-01-01

Protecting astronauts' spine, hip, and lower body musculoskeletal strength will be critical to safely and efficiently perform physically demanding vehicle egress, exploration, and habitat building activities necessary to expand human presence in the solar system. Functionally limiting decrements in musculoskeletal health are likely during Mars proving-ground and Earth-independent missions given extended transit times and the vehicle limitations for exercise devices (low-mass, small volume). Most small exercise device concepts are designed with single-cable loading, which inhibits the ability to perform full body exercises requiring two-point loading at the shoulders. Shoulder loading is critical to protect spine, hip, and lower body musculoskeletal strength. We propose a novel low-mass, low-maintenance, and rapid deploy pulley-based system that can attach to a single-cable small exercise device to enable two-point loading at the shoulders. This attachment could protect astronauts' health and save cost, space, and energy during all phases of the Journey to Mars.

The Critical Compression Load for a Universal Testing Machine When the Specimen Is Loaded Through Knife Edges

NASA Technical Reports Server (NTRS)

Lundquist, Eugene E; Schwartz, Edward B

1942-01-01

The results of a theoretical and experimental investigation to determine the critical compression load for a universal testing machine are presented for specimens loaded through knife edges. The critical load for the testing machine is the load at which one of the loading heads becomes laterally instable in relation to the other. For very short specimens the critical load was found to be less than the rated capacity given by the manufacturer for the machine. A load-length diagram is proposed for defining the safe limits of the test region for the machine. Although this report is particularly concerned with a universal testing machine of a certain type, the basic theory which led to the derivation of the general equation for the critical load, P (sub cr) = alpha L can be applied to any testing machine operated in compression where the specimen is loaded through knife edges. In this equation, L is the length of the specimen between knife edges and alpha is the force necessary to displace the upper end of the specimen unit horizontal distance relative to the lower end of the specimen in a direction normal to the knife edges through which the specimen is loaded.

Material Selection for Cable Gland to Improved Reliability of the High-hazard Industries

NASA Astrophysics Data System (ADS)

Vashchuk, S. P.; Slobodyan, S. M.; Deeva, V. S.; Vashchuk, D. S.

2018-01-01

The sealed cable glands (SCG) are available to ensure safest connection sheathed single wire for the hazard production facility (nuclear power plant and others) the same as pilot cable, control cables, radio-frequency cables et al. In this paper, we investigate the specifics of the material selection of SCG with the express aim of hazardous man-made facility. We discuss the safe working conditions for cable glands. The research indicates the sintering powdered metals cables provide the reliability growth due to their properties. A number of studies have demonstrated the verification of material selection. On the face of it, we make findings indicating that double glazed sealed units could enhance reliability. We had evaluated sample reliability under fire conditions, seismic load, and pressure containment failure. We used the samples mineral insulated thermocouple cable.

Post-earthquake traffic capacity of modern bridges in California.

DOT National Transportation Integrated Search

2010-03-01

Evaluation of the capacity of a bridge to carry self-weight and traffic loads after an earthquake is essential for a safe and timely re-opening of the bridge. In California, modern highway bridges designed using the Caltrans Seismic Design Criteria a...

Post-Earthquake Traffic Capacity of Modern Bridges in California

DOT National Transportation Integrated Search

2010-03-01

Evaluation of the capacity of a bridge to carry self-weight and traffic loads after an earthquake is essential for a : safe and timely re-opening of the bridge. In California, modern highway bridges designed using the Caltrans : Seismic Design Criter...

42 CFR 65.1 - To what projects do these regulations apply?

Code of Federal Regulations, 2010 CFR

2010-10-01

..., INTERNSHIPS, TRAINING NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES HAZARDOUS WASTE WORKER TRAINING § 65... for the purpose of providing training and education to hazardous materials employees regarding: the safe unloading, loading, handling, storage, and transportation of hazardous materials; and, emergency...

Slosh characteristics of aggregated intermediate bulk containers on single-unit trucks.

DOT National Transportation Integrated Search

2016-08-01

Drivers of cargo tank trucks need special knowledge of vehicle and load dynamics, including slosh, to handle their vehicles safely. This knowledge is reflected by a tank vehicle (N) endorsement to the commercial drivers license (CDL). Drivers of v...

49 CFR 393.100 - Which types of commercial motor vehicles are subject to the cargo securement standards of this...

Code of Federal Regulations, 2011 CFR

2011-10-01

... AND ACCESSORIES NECESSARY FOR SAFE OPERATION Protection Against Shifting and Falling Cargo § 393.100..., spilling, blowing or falling from the motor vehicle. (c) Prevention against shifting of load. Cargo must be...

49 CFR 393.100 - Which types of commercial motor vehicles are subject to the cargo securement standards of this...

Code of Federal Regulations, 2012 CFR

2012-10-01

... AND ACCESSORIES NECESSARY FOR SAFE OPERATION Protection Against Shifting and Falling Cargo § 393.100..., spilling, blowing or falling from the motor vehicle. (c) Prevention against shifting of load. Cargo must be...

49 CFR 393.100 - Which types of commercial motor vehicles are subject to the cargo securement standards of this...

Code of Federal Regulations, 2014 CFR

2014-10-01

... AND ACCESSORIES NECESSARY FOR SAFE OPERATION Protection Against Shifting and Falling Cargo § 393.100..., spilling, blowing or falling from the motor vehicle. (c) Prevention against shifting of load. Cargo must be...

49 CFR 393.100 - Which types of commercial motor vehicles are subject to the cargo securement standards of this...

Code of Federal Regulations, 2010 CFR

2010-10-01

... AND ACCESSORIES NECESSARY FOR SAFE OPERATION Protection Against Shifting and Falling Cargo § 393.100..., spilling, blowing or falling from the motor vehicle. (c) Prevention against shifting of load. Cargo must be...

49 CFR 393.100 - Which types of commercial motor vehicles are subject to the cargo securement standards of this...

Code of Federal Regulations, 2013 CFR

2013-10-01

... AND ACCESSORIES NECESSARY FOR SAFE OPERATION Protection Against Shifting and Falling Cargo § 393.100..., spilling, blowing or falling from the motor vehicle. (c) Prevention against shifting of load. Cargo must be...

Insert Design and Manufacturing for Foam-Core Composite Sandwich Structures

NASA Astrophysics Data System (ADS)

Lares, Alan

Sandwich structures have been used in the aerospace industry for many years. The high strength to weight ratios that are possible with sandwich constructions makes them desirable for airframe applications. While sandwich structures are effective at handling distributed loads such as aerodynamic forces, they are prone to damage from concentrated loads at joints or due to impact. This is due to the relatively thin face-sheets and soft core materials typically found in sandwich structures. Carleton University's Uninhabited Aerial Vehicle (UAV) Project Team has designed and manufactured a UAV (GeoSury II Prototype) which features an all composite sandwich structure fuselage structure. The purpose of the aircraft is to conduct geomagnetic surveys. The GeoSury II Prototype serves as the test bed for many areas of research in advancing UAV technologies. Those areas of research include: low cost composite materials manufacturing, geomagnetic data acquisition, obstacle detection, autonomous operations and magnetic signature control. In this thesis work a methodology for designing and manufacturing inserts for foam-core sandwich structures was developed. The results of this research work enables a designer wishing to design a foam-core sandwich airframe structure, a means of quickly manufacturing optimized inserts for the safe introduction of discrete loads into the airframe. The previous GeoSury II Prototype insert designs (v.1 & v.2) were performance tested to establish a benchmark with which to compare future insert designs. Several designs and materials were considered for the new v.3 inserts. A plug and sleeve design was selected, due to its ability to effectively transfer the required loads to the sandwich structure. The insert material was chosen to be epoxy, reinforced with chopped carbon fibre. This material was chosen for its combination of strength, low mass and also compatibility with the face-sheet material. The v.3 insert assembly is 60% lighter than the previous insert designs. A casting process for manufacturing the v.3 inserts was developed. The developed casting process, when producing more than 13 inserts, becomes more economical than machining. An exploratory study was conducted looking at the effects of dynamic loading on the v.3 insert performance. The results of this study highlighted areas for improving dynamic testing of foam-core sandwich structure inserts. Correlations were developed relating design variables such as face-sheet thickness and insert diameter to a failure load for different load cases. This was done through simulations using Computer Aided Engineering (CAE) software, and experimental testing. The resulting correlations were integrated into a computer program which outputs the required insert dimensions given a set of design parameters, and load values.

Functional connectivity among multi-channel EEGs when working memory load reaches the capacity.

PubMed

Zhang, Dan; Zhao, Huipo; Bai, Wenwen; Tian, Xin

2016-01-15

Evidence from behavioral studies has suggested a capacity existed in working memory. As the concept of functional connectivity has been introduced into neuroscience research in the recent years, the aim of this study is to investigate the functional connectivity in the brain when working memory load reaches the capacity. 32-channel electroencephalographs (EEGs) were recorded for 16 healthy subjects, while they performed a visual working memory task with load 1-6. Individual working memory capacity was calculated according to behavioral results. Short-time Fourier transform was used to determine the principal frequency band (theta band) related to working memory. The functional connectivity among EEGs was measured by the directed transform function (DTF) via spectral Granger causal analysis. The capacity was 4 calculated from the behavioral results. The power was focused in the frontal midline region. The strongest connectivity strengths of EEG theta components from load 1 to 6 distributed in the frontal midline region. The curve of DTF values vs load numbers showed that DTF increased from load 1 to 4, peaked at load 4, then decreased after load 4. This study finds that the functional connectivity between EEGs, described quantitatively by DTF, became less strong when working memory load exceeded the capacity. Copyright © 2015 Elsevier B.V. All rights reserved.

Picture Me Safe

ERIC Educational Resources Information Center

Irvin, Daniel W.

1977-01-01

The validity of well-written articles can be destroyed by poor illustration, especially when the pictures show unsafe practices. The responsibility lies with the author to provide clear printable pictures showing safe working environments and safe practices. (Editor)

Health Care Ergonomics: Contributions of Thomas Waters.

PubMed

Poole Wilson, Tiffany; Davis, Kermit G

2016-08-01

The aim of this study was to assess the contributions of Thomas Waters's work in the field of health care ergonomics and beyond. Waters's research of safe patient handling with a focus on reducing musculoskeletal disorders (MSDs) in health care workers contributed to current studies and prevention strategies. He worked with several groups to share his research and assist in developing safe patient handling guidelines and curriculum for nursing students and health care workers. The citations of articles that were published by Waters in health care ergonomics were evaluated for quality and themes of conclusions. Quality was assessed using the Mixed Methods Appraisal Tool and centrality to original research rating. Themes were documented by the type of population the citing articles were investigating. In total, 266 articles that referenced the top seven cited articles were evaluated. More than 95% of them were rated either medium or high quality. The important themes of these citing articles were as follows: (a) Safe patient handling is effective in reducing MSDs in health care workers. (b) Shift work has negative impact on nurses. (c) There is no safe way to manually lift a patient. (d) Nurse curriculums should contain safe patient handling. The research of Waters has contributed significantly to the health care ergonomics and beyond. His work, in combination with other pioneers in the field, has generated multiple initiatives, such as a standard safe patient-handling curriculum and safe patient-handling programs. © 2016, Human Factors and Ergonomics Society.

Qualification Motor no. 8 (QM-8), volume 1

NASA Technical Reports Server (NTRS)

Garecht, D. M.

1989-01-01

All inspection and instrumentation data indicate that the QM-8 static test firing conducted 20 January 1989 was successful. Ambient temperature at T-0 was 28 F. With two flights successfully accomplished, this final test in the redesigned solid rocket motor (RSRM) program certified that the design meets motor performance requirements under extreme cold conditions. This test was a prerequisite to the third flight. The entire test article was cold conditioned at 20 to 25 F for approximately 31 days to assure a maximum propellant mean bulk temperature (PMBT) of 40 F, making it the lowest PMBT in the history of the program. This extreme condition also presented the opportunity to certify critical components at low temperatures. Certification of field joint and igniter heaters, adhesive bondline integrity, flex bearing performance, flight instrumentation performance, RSRM seal performance, and LSC and nozzle plug performance was accomplished. Prior to motor ignition, the field joints were maintained between 75 to 130 F, the igniter-to-case joint was maintained between 75 to 123 F, and the case-to-nozzle joint was maintained between 75 to 120 F. QM-8 was tested with induced side loads to simulate the strut loads experienced during ignition and maximum aerodynamic loading conditions. The ability of the safe and arm device to change position from safe-to-arm and arm-to-safe was certified. Ballistics performance was certified at the lower limits. Values were within specification requirements. Nozzle performance was nominal with typical erosion. The use of Fiberite carbon-cloth phenolic was certified. The water deluge system, CO2 quench, and other test equipment performed as planned during all required test operations.

75 FR 23561 - Workers Memorial Day, 2010

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-04

... renewing our Nation's commitment to achieve safe working conditions for all American workers. Providing..., which promise American workers the right to a safe workplace and require employers to provide safe...--but they are not forgotten. The legal right to a safe workplace was won only after countless lives had...

Co-creating Emotionally Safe Environments at Camp: Training Staff To Facilitate Adventure Activities.

ERIC Educational Resources Information Center

Brownlee, Matt; Yerkes, Rita

2003-01-01

An emotionally safe environment helps campers participate in adventure activities. Staff development tips for creating a safe environment include using cooperative goal setting; using parallel training processes; developing working lesson plans that outline facilitation techniques for creating emotionally safe environments; and using co-created…

Population, desert expanding.

PubMed

1992-01-01

The conditions of desert expansion in the Sahara are highlighted. On the southern border the desert is growing at a rate of 3-6 miles/year. This growth is encroaching on arable land in Ethiopia and Mauritania. The region loses up to 28,000 sq miles/year of farmland. 33% of Africa's fertile land is threatened. Land-use patterns are responsible for the deterioration of the soil. Traditional practices are not effective because the practices are not suitable for permanent farming. Farmers also have stopped environmentally sound practices such as letting the fields remain fallow in order to renew soil fertility. Nomads overgraze areas before moving on. A recent study by the World Bank's Africa Region Office was released; the report details some of the links between rapid population growth, poor agricultural performance, and environmental degradation. Soil conditions are such that valuable topsoil is blow away by the wind because the layer is too thin. Vegetation at the desert's edge is used for cooking purposes or for heating fuel. Tropical and savannah areas are depleted when tree replacement is inadequate. Only 9 trees are planted for every 100 removed. The report emphasized the role of women and children in contributing to population pressure by increased fertility. Women's work load is heavy and children are a help in alleviating some of the burden of domestic and agricultural work. There is hope in meeting demographic, agricultural, food security, and environmental objectives over the next 30 years if the needs of women are met. The needs include access to education for young women, lessening the work loads of women, and decreasing child mortality through improved health care and access to safe water.

Principles in wireless building health monitoring systems.

NASA Astrophysics Data System (ADS)

Pentaris, F. P.; Makris, J. P.; Stonham, J.; Vallianatos, F.

2012-04-01

Monitoring the structural state of a building is essential for the safety of the people who work, live, visit or just use it as well as for the civil protection of urban areas. Many factors can affect the state of the health of a structure, namely man made, like mistakes in the construction, traffic, heavy loads on the structures, explosions, environmental impacts like wind loads, humidity, chemical reactions, temperature changes and saltiness, and natural hazards like earthquakes and landslides. Monitoring the health of a structure provides the ability to anticipate structural failures and secure the safe use of buildings especially those of public services. This work reviews the state of the art and the challenges of a wireless Structural Health Monitoring (WiSHM). Literature review reveals that although there is significant evolution in wireless structural health monitoring, in many cases, monitoring by itself is not enough to predict when a structure becomes inappropriate and/or unsafe for use, and the damage or low durability of a structure cannot be revealed (Chintalapudi, et al., 2006; Ramos, Aguilar, & Lourenço, 2011). Several features and specifications of WiSHM like wireless sensor networking, reliability and autonomy of sensors, algorithms of data transmission and analysis should still be evolved and improved in order to increase the predictive effectiveness of the SHM (Jinping Ou & Hui Li, 2010; Lu & Loh, 2010) . Acknowledgments This work was supported in part by the ARCHEMEDES III Program of the Ministry of Education of Greece and the European Union in the framework of the project entitled «Interdisciplinary Multi-Scale Research of Earthquake Physics and Seismotectonics at the front of the Hellenic Arc (IMPACT-ARC) ».

An automated spring-loaded needle for endoscopic ultrasound-guided abdominal paracentesis in cancer patients

PubMed Central

Suzuki, Rei; Irisawa, Atsushi; Bhutani, Manoop S; Hikichi, Takuto; Takagi, Tadayuki; Shibukawa, Goro; Sato, Ai; Sato, Masaki; Ikeda, Tsunehiko; Watanabe, Ko; Nakamura, Jun; Annangi, Srinadh; Tasaki, Kazuhiro; Obara, Katsutoshi; Ohira, Hiromasa

2014-01-01

AIM: To evaluate the feasibility of using an automated spring-loaded needle device for endoscopic ultrasound (EUS)-guided abdominal paracentesis (EUS-P) to see if this would make it easier to puncture the mobile and lax gastric wall for EUS-P. METHODS: The EUS database and electronic medical records at Fukushima Medical University Hospital were searched from January 2001 to April 2011. Patients with a history of cancer and who underwent EUS-P using an automated spring-loaded needle device with a 22-gauge puncture needle were included. The needle was passed through the instrument channel and advanced through the gastrointestinal wall under EUS guidance into the echo-free space in the abdominal cavity and ascitic fluid was collected. The confirmed diagnosis of malignant ascites included positive cytology and results from careful clinical observation for at least 6 mo in patients with negative cytology. The technical success rate, cytology results and complications were evaluated. RESULTS: We found 11 patients who underwent EUS-P with an automated spring-loaded needle device. In 4 cases, ascites was revealed only with EUS but not in other imaging modalities. EUS-P was done in 7 other cases because there was minimal ascitic fluid and no safe window for percutaneous abdominal aspiration. Ascitic fluid was obtained in all cases by EUS-P. The average amount aspirated was 14.1 mL (range 0.5-38 mL) and that was sent for cytological exam. The etiology of ascitic fluid was benign in 5 patients and malignant in 6. In all cases, ascitic fluid was obtained with the first needle pass. No procedure-related adverse effects occurred. CONCLUSION: EUS-P with an automated spring-loaded needle device is a feasible and safe method for ascites evaluation. PMID:24567793

Residual strength of thin panels with cracks

NASA Technical Reports Server (NTRS)

Madenci, Erdogan

1994-01-01

The previous design philosophies involving safe life, fail-safe and damage tolerance concepts become inadequate for assuring the safety of aging aircraft structures. For example, the failure mechanism for the Aloha Airline accident involved the coalescence of undetected small cracks at the rivet holes causing a section of the fuselage to peel open during flight. Therefore, the fuselage structure should be designed to have sufficient residual strength under worst case crack configurations and in-flight load conditions. Residual strength is interpreted as the maximum load carrying capacity prior to unstable crack growth. Internal pressure and bending moment constitute the two major components of the external loads on the fuselage section during flight. Although the stiffeners in the form of stringers, frames and tear straps sustain part of the external loads, the significant portion of the load is taken up by the skin. In the presence of a large crack in the skin, the crack lips bulge out with considerable yielding; thus, the geometric and material nonlinearities must be included in the analysis for predicting residual strength. Also, these nonlinearities do not permit the decoupling of in-plane and out-of-plane bending deformations. The failure criterion combining the concepts of absorbed specific energy and strain energy density addresses the aforementioned concerns. The critical absorbed specific energy (local toughness) for the material is determined from the global specimen response and deformation geometry based on the uniaxial tensile test data and detailed finite element modeling of the specimen response. The use of the local toughness and stress-strain response at the continuum level eliminates the size effect. With this critical parameter and stress-strain response, the finite element analysis of the component by using STAGS along with the application of this failure criterion provides the stable crack growth calculations for residual strength predictions.

A Statistical Simulation Approach to Safe Life Fatigue Analysis of Redundant Metallic Components

NASA Technical Reports Server (NTRS)

Matthews, William T.; Neal, Donald M.

1997-01-01

This paper introduces a dual active load path fail-safe fatigue design concept analyzed by Monte Carlo simulation. The concept utilizes the inherent fatigue life differences between selected pairs of components for an active dual path system, enhanced by a stress level bias in one component. The design is applied to a baseline design; a safe life fatigue problem studied in an American Helicopter Society (AHS) round robin. The dual active path design is compared with a two-element standby fail-safe system and the baseline design for life at specified reliability levels and weight. The sensitivity of life estimates for both the baseline and fail-safe designs was examined by considering normal and Weibull distribution laws and coefficient of variation levels. Results showed that the biased dual path system lifetimes, for both the first element failure and residual life, were much greater than for standby systems. The sensitivity of the residual life-weight relationship was not excessive at reliability levels up to R = 0.9999 and the weight penalty was small. The sensitivity of life estimates increases dramatically at higher reliability levels.

A multidisciplinary approach of workload assessment in real-job situations: investigation in the field of aerospace activities.

PubMed

Mélan, Claudine; Cascino, Nadine

2014-01-01

The present contribution presents two field studies combining tools and methods from cognitive psychology and from occupational psychology in order to perform a thorough investigation of workload in employees. Cognitive load theory proposes to distinguish different load categories of working memory, in a context of instruction. Intrinsic load is inherent to the task, extraneous load refers to components of a learning environment that may be modified to reduce total load, and germane load enables schemas construction and thus efficient learning. We showed previously that this theoretical framework may be successfully extended to working memory tasks in non-instructional designs. Other theoretical models, issued from the field of occupational psychology, account for an individual's perception of work demands or requirements in the context of different psychosocial features of the (work) environment. Combining these approaches is difficult as workload assessment by job-perception questionnaires explore an individual's overall job-perception over a large time-period, whereas cognitive load investigations in working memory tasks are typically performed within short time-periods. We proposed an original methodology enabling investigation of workload and load factors in a comparable time-frame. We report two field studies investigating workload on different shift-phases and between work-shifts, with two custom-made tools. The first one enabled workload assessment by manipulating intrinsic load (task difficulty) and extraneous load (time pressure) in a working-memory task. The second tool was a questionnaire based on the theoretical concepts of work-demands, control, and psychosocial support. Two additional dimensions suspected to contribute to job-perception, i.e., work-family conflicts and availability of human and technical resources were also explored. Results of workload assessments were discussed in light of operators' alertness and job-performance.

Assessment of the Acceptability and Feasibility of Child Potties for Safe Child Feces Disposal in Rural Bangladesh

PubMed Central

Hussain, Faruqe; Luby, Stephen P.; Unicomb, Leanne; Leontsini, Elli; Naushin, Tania; Buckland, Audrey J.; Winch, Peter J.

2017-01-01

Abstract. Indiscriminate defecation among young children and the unsafe disposal of their feces increases fecal contamination in the household environment and the risk of diarrheal disease transmission. Improved sanitary technology for children too young to use a latrine may facilitate safe feces disposal and reduce fecal contamination in the household environment. We assessed the acceptability and feasibility of child potties in rural Bangladesh in 2010. Our team introduced child potties into 26 households for 30 days, and conducted semistructured interviews, group discussions, and observations to assess the acceptability and feasibility of their use for parents and children. Residents of this rural Bangladeshi community accepted the child potties and caregivers found them to be a feasible means of managing child feces. The color, shape, design, and size of the potty influenced its acceptability and use. These residents reported that regular use of the potty improved the household’s physical environment and caregiver and child personal hygiene. Regular potty use also reduced caregivers’ work load by making feces collection and disposal easier. Primary caregivers viewed 4–6 months as the appropriate age to initiate potty training. Sanitation interventions should integrate and emphasize potties for children’s feces management to reduce household environmental contamination. PMID:28722606

Determination of Offgassed Products

NASA Technical Reports Server (NTRS)

1997-01-01

A technician at Marshall Space Flight Center's Materials Combustion Research Facility begins the Determination of Offgassed Products Test to determine the identity and quantity of volatile offgassed products from materials and assembled articles. Materials are measured, weighed, and loaded into a clean toxicity chamber (pictured). The chamber is purged with high-purity air and loaded into an oven where it will be held at 120 degrees Fahrenheit (48.9 degrees Celsius) for 72 hours. At the end of the 72-hour period, the chamber is removed and allowed to cool to room temperature. Gas samples are taken from the chamber and analyzed using gas chromatography and mass spectrometry. From this, the quantity of the material that may be used safely in habitable areas of spacecraft is determined. This test also determines whether a flight hardware item may be flown safely in a crew compartment. Everything going into space with the astronauts is tested prior to flight to ensure the health and safety of the crew members.

Ensemble coding remains accurate under object and spatial visual working memory load.

PubMed

Epstein, Michael L; Emmanouil, Tatiana A

2017-10-01

A number of studies have provided evidence that the visual system statistically summarizes large amounts of information that would exceed the limitations of attention and working memory (ensemble coding). However the necessity of working memory resources for ensemble coding has not yet been tested directly. In the current study, we used a dual task design to test the effect of object and spatial visual working memory load on size averaging accuracy. In Experiment 1, we tested participants' accuracy in comparing the mean size of two sets under various levels of object visual working memory load. Although the accuracy of average size judgments depended on the difference in mean size between the two sets, we found no effect of working memory load. In Experiment 2, we tested the same average size judgment while participants were under spatial visual working memory load, again finding no effect of load on averaging accuracy. Overall our results reveal that ensemble coding can proceed unimpeded and highly accurately under both object and spatial visual working memory load, providing further evidence that ensemble coding reflects a basic perceptual process distinct from that of individual object processing.

Characterization of Aircraft Structural Damage Using Guided Wave Based Finite Element Analysis for In-Flight Structural Health Management

NASA Technical Reports Server (NTRS)

Seshadri, Banavara R.; Krishnamurthy, Thiagarajan; Ross, Richard W.

2016-01-01

The development of multidisciplinary Integrated Vehicle Health Management (IVHM) tools will enable accurate detection, diagnosis and prognosis of damage under normal and adverse conditions during flight. The adverse conditions include loss of control caused by environmental factors, actuator and sensor faults or failures, and structural damage conditions. A major concern is the growth of undetected damage/cracks due to fatigue and low velocity foreign object impact that can reach a critical size during flight, resulting in loss of control of the aircraft. To avoid unstable catastrophic propagation of damage during a flight, load levels must be maintained that are below the load-carrying capacity for damaged aircraft structures. Hence, a capability is needed for accurate real-time predictions of safe load carrying capacity for aircraft structures with complex damage configurations. In the present work, a procedure is developed that uses guided wave responses to interrogate damage. As the guided wave interacts with damage, the signal attenuates in some directions and reflects in others. This results in a difference in signal magnitude as well as phase shifts between signal responses for damaged and undamaged structures. Accurate estimation of damage size and location is made by evaluating the cumulative signal responses at various pre-selected sensor locations using a genetic algorithm (GA) based optimization procedure. The damage size and location is obtained by minimizing the difference between the reference responses and the responses obtained by wave propagation finite element analysis of different representative cracks, geometries and sizes.

The hybrid assistive limb (HAL) for Care Support successfully reduced lumbar load in repetitive lifting movements.

PubMed

Miura, Kousei; Kadone, Hideki; Koda, Masao; Abe, Tetsuya; Kumagai, Hiroshi; Nagashima, Katsuya; Mataki, Kentaro; Fujii, Kengo; Noguchi, Hiroshi; Funayama, Toru; Kawamoto, Hiroaki; Sankai, Yoshiyuki; Yamazaki, Masashi

2018-05-03

Work-related low back pain is a serious socioeconomic problem. This study examined whether HAL for Care Support, which is a newly developed wearable robot, would decrease lumbar fatigue and improve lifting performance during repetitive lifting movements. Eighteen healthy volunteers (11 men, 7 women) performed repetitive stoop lifting movements of a cardboard box weighing 12 kg as many times as possible. The first lifting trial was executed without HAL for Care Support, and the second was with it. We evaluated the VAS of lumbar fatigue as the lumbar load and the number of lifts and the lifting time as lifting performance. Without HAL for Care Support, the mean VAS of lumbar fatigue, the number of lifts and lifting time were 68 mm, 60 and 230 s; with HAL for Care Support, they were 51 mm, 87 and 332 s, respectively. Both lifting performance measures were significantly improved by using HAL for Care Support (Fig. 2). A power analysis showed that there was sufficient statistical power for the VAS of lumbar fatigue (0.99), the number of lifts (0.92), and lifting time (0.93). All participants performed their repetitive lifting trials safely. There were no adverse events caused by using HAL for Care Support. In conclusion, the HAL for Care Support can decrease lumbar load and improve the lifting performance during repetitive stoop lifting movements in healthy adults. Copyright © 2018. Published by Elsevier Ltd.

Effect of aeration rate and waste load on evolution of volatile fatty acids and waste stabilization during thermophilic aerobic digestion of a model high strength agricultural waste.

PubMed

Ugwuanyi, J Obeta; Harvey, L M; McNeil, B

2005-04-01

Thermophilic aerobic digestion (TAD) is a relatively new, dynamic and versatile low technology for the economic processing of high strength waste slurries. Waste so treated may be safely disposed of or reused. In this work a model high strength agricultural waste, potato peel, was subjected to TAD to study the effects of oxygen supply at 0.1, 0.25, 0.5 and 1.0 vvm (volume air per volume slurry per minute) under batch conditions at 55 degrees C for 156 h on the process. Process pH was controlled at 7.0 or left unregulated. Effects of waste load, as soluble chemical oxygen demand (COD), on TAD were studied at 4.0, 8.0, 12.0 and 16.0 gl(-1) (soluble COD) at pH 7.0, 0.5 vvm and 55 degrees C. Efficiency of treatment, as degradation of total solids, total suspended solids and soluble solid, as well as soluble COD significantly increased with aeration rate, while acetate production increased as the aeration rate decreased or waste load increased, signifying deterioration in treatment. Negligible acetate, and no other acids were produced at 1.0 vvm. Production of propionate and other acids increased after acetate concentration had started to decrease and, during unregulated reactions coincided with the drop in the pH of the slurry. Acetate production was more closely associated with periods of oxygen limitation than were other acids. Reduction in oxygen availability led to deterioration in treatment efficiency as did increase in waste load. These variables may be manipulated to control treated waste quality.

Study on power grid characteristics in summer based on Linear regression analysis

NASA Astrophysics Data System (ADS)

Tang, Jin-hui; Liu, You-fei; Liu, Juan; Liu, Qiang; Liu, Zhuan; Xu, Xi

2018-05-01

The correlation analysis of power load and temperature is the precondition and foundation for accurate load prediction, and a great deal of research has been made. This paper constructed the linear correlation model between temperature and power load, then the correlation of fault maintenance work orders with the power load is researched. Data details of Jiangxi province in 2017 summer such as temperature, power load, fault maintenance work orders were adopted in this paper to develop data analysis and mining. Linear regression models established in this paper will promote electricity load growth forecast, fault repair work order review, distribution network operation weakness analysis and other work to further deepen the refinement.

Texas passes first law for safe patient handling in America: landmark legislation protects health-care workers and patients from injury related to manual patient lifting.

PubMed

Hudson, Mary Anne

2005-01-01

On June 17,2005, Texas Governor Rick Perry (R) signed into law Senate Bill 1525, making Texas the first state in the nation to require hospitals and nursing homes to implement safe patient handling and movement programs. Governor Perry is to be commended for this heroic first stand for safe patient handling in America. The landmark legislation will take effect January 1, 2006, requiring the establishment of policy to identify, assess, and develop methods of controlling the risk of injury to patients and nurses associated with lifting, transferring, repositioning, and movement of patients; evaluation of alternative methods from manual lifting to reduce the risk of injury from patient lifting, including equipment and patient care environment; restricting, to the extent feasible with existing equipment, manual handling of all or most of a patient's weight to emergency, life-threatening, or exceptional circumstances; and provision for refusal to perform patient handling tasks believed to involve unacceptable risks of injury to a patient or nurse. Manually lifting patients has been called deplorable, inefficient, dangerous to nurses, and painful and brutal to patients; manual lifting can cause needless suffering and injury to patients, with dangers including pain, bruising, skin tears, abrasions, tube dislodgement, dislocations, fractures, and being dropped by nursing staff during attempts to manually lift. Use of safe, secure, mechanical lift equipment and gentle friction-reducing devices for patient maneuvering tasks could eliminate such needless brutality. Research has proven that manual patient lifting is extremely hazardous to health-care workers, creating substantial risk of low-back injury, whether with one or two patient handlers. Studies on the use of mechanical patient lift equipment, by either nursing staff or lift teams, have proven repeatedly that most nursing staff back injury is preventable, leading to substantial savings to employers on medical and compensation costs. Because the health-care industry has relied on people to do the work of machines, nursing work remains the most dangerous occupation for disabling back injury. Back injury from patient lifting may be the single largest contributor to the nursing shortage, with perhaps 12% of nurses leaving or being terminated because of back injury. The US health-care industry has not kept pace with other industries, which provide mechanical lift equipment for lifting loads equivalent to the weight of patients, or with other countries, such as Australia and England, which are more advanced in their use of modern technology for patient lifting and with no-lifting practices in compliance with government regulations and nursing policies banning manual lifting. With Texas being the first state to succeed in passing legislation for safe patient handling, other states are working toward legislative protection against injury with manual patient lifting. California re-introduced safe patient handling legislation on February 17, 2005, with CA SB 363, Hospitals: Lift Teams, following the September 22, 2004, veto of CA AB 2532 by Governor Arnold Schwarzenegger, who said he believes existing statutory protection and workplace safety standards are sufficient to protect health care workers from injury. Massachusetts HB 2662, Relating to Safe Patient Handling in Certain Health Facilities, was introduced December 1, 2004. Ohio HB 67, signed March 21, 2005 by Governor Bob Taft (R), creates a program for interest-free loans to nursing homes for implementation of a no-manual-lift program. New York companion bills AB 7641 and SB 4029 were introduced in April, 2005, calling for creation of a 2-year study to establish safe patient handling programs and collect data on nursing staff and patient injury with manual patient handling versus lift equipment, to determine best practices for improving health and safety of health-care workers and patients during patient handling. Washington State is planning re-introduction of safe patient handling legislation, after WA HB 1672, Relating to reducing injuries among patients and health care workers, was stalled in committee in February, 2005. Language from these state initiatives may be used as models to assist other states with drafting safe patient handling legislation. Rapid enactment of a federal mandate for Safe Patient Handling No Manual Lift is essential and anticipated.

[Rural work and health risks: a review into de "safe use" of pesticides in Brazil].

PubMed

de Abreu, Pedro Henrique Barbosa; Alonzo, Herling Gregorio Aguilar

2014-10-01

The paradigm of the "safe use" of pesticides is based on measures to control risks in the handling of these products. However, studies carried out in various regions of Brazil reveal a situation of widespread exposure and health damages among rural workers, revealing the ineffectiveness of this paradigm. This work presents a critical review of the "safe use" approach for pesticides in scientific papers published in Brazil in the past 15 years. Results indicate that these studies do not address, simultaneously, all the work activities that involve exposure and risk of intoxication (acquisition, transportation, storage, preparation and application, final disposal of empty containers and sanitization of contaminated clothes/ PPEs), nor do they comprehensively address the "safe use" measures recommended in safety manuals, which are mandatory for each activity. A total of 25 studies were selected and analyzed, revealing a high number of results and analyses regarding activities of preparation and application and final disposal of empty containers. The range of the approaches was seen to be timely in the six work activities. For future studies, a broader approach of the "safe use" of pesticides is recommended, seeking to reveal the complete infeasibility of this safety paradigm.

Nurses' experiences and perspectives on medication safety practices: an explorative qualitative study.

PubMed

Smeulers, Marian; Onderwater, Astrid T; van Zwieten, Myra C B; Vermeulen, Hester

2014-04-01

To explore nurses' experiences with and perspectives on preventing medication administration errors. Insight into nurses' experiences with and perspectives on preventing medication administration errors is important and can be utilised to tailor and implement safety practices. A qualitative interview study of 20 nurses in an academic medical centre was conducted between March and December of 2011. Three themes emerged from this study: (1) nurses' roles and responsibilities in medication safety: aside from safe preparation and administration, the clinical reasoning of nurses is essential for medication safety; (2) nurses' ability to work safely: knowledge of risks and nurses' work circumstances influence their ability to work safely; and (3) nurses' acceptance of safety practices: advantages, feasibility and appropriateness are important incentives for acceptance of a safety practice. Nurses' experiences coincide with the assumption that they are in a pre-eminent position to enable safe medication management; however, their ability to adequately perform this role depends on sufficient knowledge to assess the risks of medication administration and on the circumstances in which they work. Safe medication management requires a learning climate and professional practice environment that enables further development of professional nursing skills and knowledge. © 2014 John Wiley & Sons Ltd.

Spatial working memory load affects counting but not subitizing in enumeration.

PubMed

Shimomura, Tomonari; Kumada, Takatsune

2011-08-01

The present study investigated whether subitizing reflects capacity limitations associated with two types of working memory tasks. Under a dual-task situation, participants performed an enumeration task in conjunction with either a spatial (Experiment 1) or a nonspatial visual (Experiment 2) working memory task. Experiment 1 showed that spatial working memory load affected the slope of a counting function but did not affect subitizing performance or subitizing range. Experiment 2 showed that nonspatial visual working memory load affected neither enumeration efficiency nor subitizing range. Furthermore, in both spatial and nonspatial memory tasks, neither subitizing efficiency nor subitizing range was affected by amount of imposed memory load. In all the experiments, working memory load failed to influence slope, subitizing range, or overall reaction time. These findings suggest that subitizing is performed without either spatial or nonspatial working memory. A possible mechanism of subitizing with independent capacity of working memory is discussed.

Working memory load modulation of parieto-frontal connections: evidence from dynamic causal modeling

PubMed Central

Ma, Liangsuo; Steinberg, Joel L.; Hasan, Khader M.; Narayana, Ponnada A.; Kramer, Larry A.; Moeller, F. Gerard

2011-01-01

Previous neuroimaging studies have shown that working memory load has marked effects on regional neural activation. However, the mechanism through which working memory load modulates brain connectivity is still unclear. In this study, this issue was addressed using dynamic causal modeling (DCM) based on functional magnetic resonance imaging (fMRI) data. Eighteen normal healthy subjects were scanned while they performed a working memory task with variable memory load, as parameterized by two levels of memory delay and three levels of digit load (number of digits presented in each visual stimulus). Eight regions of interest, i.e., bilateral middle frontal gyrus (MFG), anterior cingulate cortex (ACC), inferior frontal cortex (IFC), and posterior parietal cortex (PPC), were chosen for DCM analyses. Analysis of the behavioral data during the fMRI scan revealed that accuracy decreased as digit load increased. Bayesian inference on model structure indicated that a bilinear DCM in which memory delay was the driving input to bilateral PPC and in which digit load modulated several parieto-frontal connections was the optimal model. Analysis of model parameters showed that higher digit load enhanced connection from L PPC to L IFC, and lower digit load inhibited connection from R PPC to L ACC. These findings suggest that working memory load modulates brain connectivity in a parieto-frontal network, and may reflect altered neuronal processes, e.g., information processing or error monitoring, with the change in working memory load. PMID:21692148

A gender approach to work ability and its relationship to professional and domestic work hours among nursing personnel.

PubMed

Rotenberg, Lúcia; Portela, Luciana Fernandes; Banks, Bahby; Griep, Rosane Harter; Fischer, Frida Marina; Landsbergis, Paul

2008-09-01

The association between working hours and work ability was examined in a cross-sectional study of male (N=156) and female (N=1092) nurses in three public hospitals. Working hours were considered in terms of their professional and domestic hours per week and their combined impact; total work load. Logistic regression analysis showed a significant association between total work load and inadequate work ability index (WAI) for females only. Females reported a higher proportion of inadequate WAI, fewer professional work hours but longer domestic work hours. There were no significant differences in total work load by gender. The combination of professional and domestic work hours in females seemed to best explain their lower work ability. The findings suggest that investigations into female well-being need to consider their total work load. Our male sample may have lacked sufficient power to detect a relationship between working hours and work ability.

Applying Combat Application Course Techniques to Rifle Marksmanship in Basic Combat Training (BCT): Acquisition and Retention of Skills

DTIC Science & Technology

2010-03-01

Uniform (interceptor body armor (IBA), load bearing vest (LBV), etc) • Weapons Safety • Fundamentals (Steady Position, Aiming, Breath Control, and...intent is that the Soldier must reacquire the target before he/she reengages; therefore, for safety considerations, the weapon is placed on “safe...Four rules of the range: A variation of the USMC Safety Rules as seen in MCRP 3- 01A (2001, para 3001, p. 3-1). o Treat the weapon as loaded. o Do

Challenges of safe medication practice in paediatric care--a nursing perspective.

PubMed

Star, Kristina; Nordin, Karin; Pöder, Ulrika; Edwards, I Ralph

2013-05-01

To explore nurses' experiences of handling medications in paediatric clinical practice, with a focus on factors that hinder and facilitate safe medication practices. Twenty nurses (registered nurses) from four paediatric wards at two hospitals in Sweden were interviewed in focus groups. The interviews were analysed using content analysis. Six themes emerged from the analysed interviews: the complexity specific for nurses working on paediatric wards is a hindrance to safe medication practices; nurses' concerns about medication errors cause a considerable psychological burden; the individual nurse works hard for safe medication practices and values support from other nurse colleagues; circumstances out of the ordinary are perceived as critical challenges for maintaining patient safety; nurses value clear instructions, guidelines and routines, but these are often missing, variable or changeable; management, other medical professionals, the pharmacy, the pharmaceutical industry and informatics support need to respond to the requirements of the nurses' working situations to improve safe medication practices. Weaknesses were apparent in the long chain of the medication-delivery process. A joint effort by different professions involved in that delivery process, and a nationwide collaboration between hospitals is recommended to increase safe medication practices in paediatric care. ©2013 Foundation Acta Paediatrica. Published by Blackwell Publishing Ltd.

Thermoelectric Exhaust Heat Recovery with Heat Pipe-Based Thermal Control

NASA Astrophysics Data System (ADS)

Brito, F. P.; Martins, Jorge; Hançer, Esra; Antunes, Nuno; Gonçalves, L. M.

2015-06-01

Heat pipe (HP)-based heat exchangers can be used for very low resistance heat transfer between a hot and a cold source. Their operating temperature depends solely on the boiling point of their working fluid, so it is possible to control the heat transfer temperature if the pressure of the HP can be adjusted. This is the case of the variable conductance HPs (VCHP). This solution makes VCHPs ideal for the passive control of thermoelectric generator (TEG) temperature levels. The present work assesses, both theoretically and experimentally, the merit of the aforementioned approach. A thermal and electrical model of a TEG with VCHP assist is proposed. Experimental results obtained with a proof of concept prototype attached to a small single-cylinder engine are presented and used to validate the model. It was found that the HP heat exchanger indeed enables the TEG to operate at a constant, optimal temperature in a passive and safe way, and with a minimal overall thermal resistance, under part load, it effectively reduces the active module area without deprecating the temperature level of the active modules.

Physical, anthropometrical, and body composition characteristics of workers at Kennedy Space Center

NASA Technical Reports Server (NTRS)

Lasley, M. L.

1985-01-01

At the Kennedy Space Center, workers are often exposed to cardiovascular and muscular stress in job-related activities which may require a high level of physical fitness in order to safely complete the work task. Similar tasks will be performed at other launch and landing facilities and in space for the Space Station. One such category includes workers who handle toxic propellants and must wear Self-Contained Atmospheric Protective Ensembles (SCAPE) that can weigh 56 lbs. with the air pack. These suits provide a significant physical challenge to many of the workers in terms of carrying this load while moving about and performing work. Furthermore, under some conditions, there is a significant thermal stress. The physical characteristics of these workers are, therefore, of consequence. The purpose of this study was to analyze the anthropometry, body composition, strength, power, endurance, flexibility, aerobic fitness, and blood variables of a representative sample of male KSC SCAPE workers and to compare them with characteristics of other male workers at KSC (total population N=110). Three separate comparisons were made.

Development of a Portable Knee Rehabilitation Device That Uses Mechanical Loading.

PubMed

Fitzwater, Daric; Dodge, Todd; Chien, Stanley; Yokota, Hiroki; Anwar, Sohel

2013-12-01

Joint loading is a recently developed mechanical modality, which potentially provides a therapeutic regimen to activate bone formation and prevent degradation of joint tissues. To our knowledge, however, few joint loading devices are available for clinical or point-of-care applications. Using a voice-coil actuator, we developed an electromechanical loading system appropriate for human studies and preclinical trials that should prove both safe and effective. Two specific tasks for this loading system were development of loading conditions (magnitude and frequency) suitable for humans, and provision of a convenient and portable joint loading apparatus. Desktop devices have been previously designed to evaluate the effects of various loading conditions using small and large animals. However, a portable knee loading device is more desirable from a usability point of view. In this paper, we present such a device that is designed to be portable, providing a compact, user-friendly loader. The portable device was employed to evaluate its capabilities using a human knee model. The portable device was characterized for force-pulse width modulation duty cycle and loading frequency properties. The results demonstrate that the device is capable of producing the necessary magnitude of forces at appropriate frequencies to promote the stimulation of bone growth and which can be used in clinical studies for further evaluations.

14 CFR 23.1353 - Storage battery design and installation.

Code of Federal Regulations, 2010 CFR

2010-01-01

... pilots to recognize the loss of generated power and take appropriate load shedding action. [Doc. No. 4080... and pressures must be maintained during any probable charging and discharging condition. No... shown that maintaining safe cell temperatures and pressures presents no problem. (d) No explosive or...

14 CFR 23.1353 - Storage battery design and installation.

Code of Federal Regulations, 2011 CFR

2011-01-01

... pilots to recognize the loss of generated power and take appropriate load shedding action. [Doc. No. 4080... and pressures must be maintained during any probable charging and discharging condition. No... shown that maintaining safe cell temperatures and pressures presents no problem. (d) No explosive or...

30 CFR 56.9309 - Chute design.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Chute design. 56.9309 Section 56.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... design. Chute-loading installations shall be designed to provide a safe location for persons pulling...

30 CFR 56.9309 - Chute design.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Chute design. 56.9309 Section 56.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... design. Chute-loading installations shall be designed to provide a safe location for persons pulling...

Crossing the Redistricting Minefield.

ERIC Educational Resources Information Center

Creighton, Roger L.; Hamlin, Douglas M.

1995-01-01

School systems are driven to redraw boundaries by population growth and changing geographic distribution of the student population. To make a safe passage, administrators must plan the crossing, prepare a comprehensive road map, and carry the community along. Goals statements should specify educational objectives as well as school loading, fiscal,…

29 CFR 1926.250 - General requirements for storage.

Code of Federal Regulations, 2010 CFR

2010-07-01

... in tiers shall be stacked, racked, blocked, interlocked, or otherwise secured to prevent sliding, falling or collapse. (2) Maximum safe load limits of floors within buildings and structures, in pounds per..., tanks, and similar storage areas shall be equipped with personal fall arrest equipment meeting the...

A multidisciplinary approach of workload assessment in real-job situations: investigation in the field of aerospace activities

PubMed Central

Mélan, Claudine; Cascino, Nadine

2014-01-01

The present contribution presents two field studies combining tools and methods from cognitive psychology and from occupational psychology in order to perform a thorough investigation of workload in employees. Cognitive load theory proposes to distinguish different load categories of working memory, in a context of instruction. Intrinsic load is inherent to the task, extraneous load refers to components of a learning environment that may be modified to reduce total load, and germane load enables schemas construction and thus efficient learning. We showed previously that this theoretical framework may be successfully extended to working memory tasks in non-instructional designs. Other theoretical models, issued from the field of occupational psychology, account for an individual’s perception of work demands or requirements in the context of different psychosocial features of the (work) environment. Combining these approaches is difficult as workload assessment by job-perception questionnaires explore an individual’s overall job-perception over a large time-period, whereas cognitive load investigations in working memory tasks are typically performed within short time-periods. We proposed an original methodology enabling investigation of workload and load factors in a comparable time-frame. We report two field studies investigating workload on different shift-phases and between work-shifts, with two custom-made tools. The first one enabled workload assessment by manipulating intrinsic load (task difficulty) and extraneous load (time pressure) in a working-memory task. The second tool was a questionnaire based on the theoretical concepts of work-demands, control, and psychosocial support. Two additional dimensions suspected to contribute to job-perception, i.e., work–family conflicts and availability of human and technical resources were also explored. Results of workload assessments were discussed in light of operators’ alertness and job-performance. PMID:25232346

Weight and See: Loading Working Memory Improves Incidental Identification of Irrelevant Faces

PubMed Central

Carmel, David; Fairnie, Jake; Lavie, Nilli

2012-01-01

Are task-irrelevant stimuli processed to a level enabling individual identification? This question is central both for perceptual processing models and for applied settings (e.g., eye-witness testimony). Lavie’s load theory proposes that working memory actively maintains attentional prioritization of relevant over irrelevant information. Loading working memory thus impairs attentional prioritization, leading to increased processing of task-irrelevant stimuli. Previous research has shown that increased working memory load leads to greater interference effects from response-competing distractors. Here we test the novel prediction that increased processing of irrelevant stimuli under high working memory load should lead to a greater likelihood of incidental identification of entirely irrelevant stimuli. To test this, we asked participants to perform a word-categorization task while ignoring task-irrelevant images. The categorization task was performed during the retention interval of a working memory task with either low or high load (defined by memory set size). Following the final experimental trial, a surprise question assessed incidental identification of the irrelevant image. Loading working memory was found to improve identification of task-irrelevant faces, but not of building stimuli (shown in a separate experiment to be less distracting). These findings suggest that working memory plays a critical role in determining whether distracting stimuli will be subsequently identified. PMID:22912623

The initial safe range of motion of the ankle joint after three methods of internal fixation of simulated fractures of the medial malleolus.

PubMed

Shimamura, Yoshio; Kaneko, Kazuo; Kume, Kazuhiko; Maeda, Mutsuhiro; Iwase, Hideaki

2006-07-01

Previous studies have demonstrated the safe passive range of ankle motion for inter-bone stiffness after internal fixation under load but there is a lack of information about the safe range of ankle motion for early rehabilitation in the absence of loading. The present study was designed to assess the effect of ankle movement on inter-bone displacement characteristics of medial malleolus fractures following three types of internal fixation to determine the safe range of motion. Five lower legs obtained during autopsy were used to assess three types of internal fixation (two with Kirschner-wires alone; two with Kirschner-wires plus tension band wiring; and, one with an AO/ASIF malleolar screw alone). Following a simulated fracture by sawing through the medial malleolus the displacement between the fractured bone ends was measured during a passive range of movement with continuous monitoring using omega (Omega) shaped transducers and a biaxial flexible goniometer. Statistical analysis was performed with repeated measures analysis of variance. Inter-bone displacement was not proportional to the magnitude of movement throughout the range of ankle motion as, when separation exceeded 25 microm, there was increasingly wide separation as plantar-flexion or dorsal-flexion was increased. There was no statistical significant difference between the small amount of inter-bone displacement observed with three types of fixation within the safe range of dorsal-flexion and plantar-flexion for early rehabilitation. However the inter-bone separation when fixation utilized two Kirschner-wires alone tended to be greater than when using the other two types of fixation during dorsal-flexion and eversion. The present study revealed a reproducible range of ankle motion for early rehabilitation which was estimated to be within the range of 20 degrees of dorsal-flexion and 10 degrees of plantar-flexion without eversion. Also, internal fixation with two Kirschner-wires alone does not seem to provide stability achieved by the other two forms of fixation.

Curvilinear relationship between phonological working memory load and social-emotional modulation

PubMed Central

Mano, Quintino R.; Brown, Gregory G.; Bolden, Khalima; Aupperle, Robin; Sullivan, Sarah; Paulus, Martin P.; Stein, Murray B.

2015-01-01

Accumulating evidence suggests that working memory load is an important factor for the interplay between cognitive and facial-affective processing. However, it is unclear how distraction caused by perception of faces interacts with load-related performance. We developed a modified version of the delayed match-to-sample task wherein task-irrelevant facial distracters were presented early in the rehearsal of pseudoword memoranda that varied incrementally in load size (1-syllable, 2-syllables, or 3-syllables). Facial distracters displayed happy, sad, or neutral expressions in Experiment 1 (N=60) and happy, fearful, or neutral expressions in Experiment 2 (N=29). Facial distracters significantly disrupted task performance in the intermediate load condition (2-syllable) but not in the low or high load conditions (1- and 3-syllables, respectively), an interaction replicated and generalised in Experiment 2. All facial distracters disrupted working memory in the intermediate load condition irrespective of valence, suggesting a primary and general effect of distraction caused by faces. However, sad and fearful faces tended to be less disruptive than happy faces, suggesting a secondary and specific valence effect. Working memory appears to be most vulnerable to social-emotional information at intermediate loads. At low loads, spare capacity is capable of accommodating the combinatorial load (1-syllable plus facial distracter), whereas high loads maximised capacity and deprived facial stimuli from occupying working memory slots to cause disruption. PMID:22928750

Exploring varieties of knowledge in safe work practices - an ethnographic study of surgical teams

PubMed Central

2011-01-01

Background Within existing research in health and medicine, the nature of knowledge on how teams conduct safe work practices has yet to be properly explored. Methods We address this concern by exploring the varieties in which knowledge is expressed during interdisciplinary surgical operations. Specifically, the study was conducted in a surgical section of a Norwegian regional general hospital, between January and April of 2010, by means of an ethnographic design combining detailed non-participant observations, conversations and semi-structured interviews. Results Based on an analysis of the gathered data, we identify three particular themes in how knowledge is expressed by operating room personnel: (i) the ability and variety individuals demonstrate in handling multiple sources of information, before reaching a particular decision, (ii) the variety of ways awareness or anticipation of future events is expressed, and (iii) the different ways sudden and unexpected situations are handled by the individual team members. Conclusions We conclude that these facets of knowledge bring different insights into how safe work practices are achieved at an individual and team level in surgical operations, thus adding to the existing understanding of the nature of knowledge in safe work practices in surgical operations. Future research should focus on exploring and documenting the relationships between various elements of knowledge and safe work practices, in different surgical settings and countries. PMID:21914183

Space Electronic Test Engineering

NASA Technical Reports Server (NTRS)

Chambers, Rodney D.

2004-01-01

The Space Power and Propulsion Test Engineering Branch at NASA Glenn Research center has the important duty of controlling electronic test engineering services. These services include test planning and early assessment of Space projects, management and/or technical support required to safely and effectively prepare the article and facility for testing, operation of test facilities, and validation/delivery of data to customer. The Space Electronic Test Engineering Branch is assigned electronic test engineering responsibility for the GRC Space Simulation, Microgravity, Cryogenic, and Combustion Test Facilities. While working with the Space Power and Propulsion Test Engineering Branch I am working on several different assignments. My primary assignment deals with an electrical hardware unit known as Sunny Boy. Sunny Boy is a DC load Bank that is designed for solar arrays in which it is used to convert DC power form the solar arrays into AC power at 60 hertz to pump back into the electricity grid. However, there are some researchers who decided that they would like to use the Sunny Boy unit in a space simulation as a DC load bank for a space shuttle or even the International Space Station hardware. In order to do so I must create a communication link between a computer and the Sunny Boy unit so that I can preset a few of the limits (such power, set & constant voltage levels) that Sunny Boy will need to operate using the applied DC load. Apart from this assignment I am also working on a hi-tech circuit that I need to have built at a researcher s request. This is a high voltage analog to digital circuit that will be used to record data from space ion propulsion rocket booster tests. The problem that makes building this circuit so difficult is that it contains high voltage we must find a way to lower the voltage signal before the data is transferred into the computer to be read. The solution to this problem was to transport the signal using infrared light which will lower the voltage signal down low enough so that it is harmless to a computer. Along with my involvement in the Space Power and Propulsion Test Engineering Branch, I am obligated to assist all other members of the branch in their work. This will help me to strengthen and extend my knowledge of Electrical Engineering.

Addendum to the User Manual for NASGRO Elastic-Plastic Fracture Mechanics Software Module

NASA Technical Reports Server (NTRS)

Gregg, M. Wayne (Technical Monitor); Chell, Graham; Gardner, Brian

2003-01-01

The elastic-plastic fracture mechanics modules in NASGRO have been enhanced by the addition of of the following: new J-integral solutions based on the reference stress method and finite element solutions; the extension of the critical crack and critical load modules for cracks with two degrees of freedom that tear and failure by ductile instability; the addition of a proof test analysis module that includes safe life analysis, calculates proof loads, and determines the flaw screening 1 capability for a given proof load; the addition of a tear-fatigue module for ductile materials that simultaneously tear and extend by fatigue; and a multiple cycle proof test module for estimating service reliability following a proof test.

An Automated Sample Divider for Farmers Stock Peanuts

USDA-ARS?s Scientific Manuscript database

In-shell peanuts are harvested, loaded into drying trailers, and delivered to a central facility where they are dried to a moisture content safe for long term storage, sampled, graded, then unloaded into bulk storage. Drying trailers have capacities ranging from five to twenty-five tons of dry farme...

An automated sample divider for farmers stock peanuts

USDA-ARS?s Scientific Manuscript database

In-shell peanuts are harvested, loaded into drying trailers, and delivered to a central facility where they are dried to a moisture content safe for long term storage, sampled, graded, then unloaded into bulk storage. Drying trailers have capacities ranging from five to twenty-five tons of dry farme...

An evaluation of child passenger safety : the effectiveness and benefits of safety seats : summary

DOT National Transportation Integrated Search

1986-02-01

The purpose of child safety seats is to reduce the number of child passengers killed or injured in motor vehicle crashes. The seats function by absorbing and safely distributing crash impact loads over the child's body while holding the child in plac...

High gantry for lifting and handling

NASA Technical Reports Server (NTRS)

Kerley, J. J., Jr.; Tereniak, W. T.

1977-01-01

Standard gantry has been inexpensively modified with standard pipes to allow lifting of heavy loads to distances between 14 and 30 ft. Addition of air mounts permits extensive and sensitive equipment to be moved smoothly and safely over smooth or moderately rough surfaces. Unit has been tested at 6000 pounds without yielding.

14 CFR 23.1353 - Storage battery design and installation.

Code of Federal Regulations, 2013 CFR

2013-01-01

... generated power and to take appropriate load shedding action. [Doc. No. 4080, 29 FR 17955, Dec. 18, 1964; 30... and pressures must be maintained during any probable charging and discharging condition. No... shown that maintaining safe cell temperatures and pressures presents no problem. (d) No explosive or...

14 CFR 23.1353 - Storage battery design and installation.

Code of Federal Regulations, 2014 CFR

2014-01-01

... generated power and to take appropriate load shedding action. [Doc. No. 4080, 29 FR 17955, Dec. 18, 1964; 30... and pressures must be maintained during any probable charging and discharging condition. No... shown that maintaining safe cell temperatures and pressures presents no problem. (d) No explosive or...

30 CFR 57.9309 - Chute design.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Chute design. 57.9309 Section 57.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....9309 Chute design. Chute-loading installations shall be designed to provide a safe location for persons...

30 CFR 57.9309 - Chute design.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Chute design. 57.9309 Section 57.9309 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND....9309 Chute design. Chute-loading installations shall be designed to provide a safe location for persons...

78 FR 3853 - Retrievability, Cladding Integrity and Safe Handling of Spent Fuel at an Independent Spent Fuel...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-17

... requirement that loaded storage casks also meet transportation requirements. Integration of storage and... transported from the storage location. As part of its evaluation of integration and compatibility between... evaluating compatibility of storage and transportation regulations. As part of its evaluation of integration...

29 CFR 1926.605 - Marine operations and equipment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... chapter. The term “longshoring operations” means the loading, unloading, moving, or handling of... surfaces of barges. (1) Employees shall not be permitted to walk along the sides of covered lighters or... a safe passage. (4) Employees shall not be permitted to walk over deckloads from rail to coaming...

33 CFR 183.33 - Maximum weight capacity: Inboard and inboard-outdrive boats.

Code of Federal Regulations, 2014 CFR

2014-07-01

... and inboard-outdrive boats. 183.33 Section 183.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.33 Maximum weight capacity: Inboard and inboard-outdrive boats. (a) The maximum weight capacity (W...

33 CFR 183.35 - Maximum weight capacity: Outboard boats.

Code of Federal Regulations, 2012 CFR

2012-07-01

... boats. 183.35 Section 183.35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.35 Maximum weight capacity: Outboard boats. (a) The maximum weight capacity marked on a boat that is designed or intended to...

33 CFR 183.33 - Maximum weight capacity: Inboard and inboard-outdrive boats.

Code of Federal Regulations, 2011 CFR

2011-07-01

... and inboard-outdrive boats. 183.33 Section 183.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.33 Maximum weight capacity: Inboard and inboard-outdrive boats. (a) The maximum weight capacity (W...

33 CFR 183.33 - Maximum weight capacity: Inboard and inboard-outdrive boats.

Code of Federal Regulations, 2012 CFR

2012-07-01

... and inboard-outdrive boats. 183.33 Section 183.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.33 Maximum weight capacity: Inboard and inboard-outdrive boats. (a) The maximum weight capacity (W...

33 CFR 183.35 - Maximum weight capacity: Outboard boats.

Code of Federal Regulations, 2014 CFR

2014-07-01

... boats. 183.35 Section 183.35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.35 Maximum weight capacity: Outboard boats. (a) The maximum weight capacity marked on a boat that is designed or intended to...

33 CFR 183.35 - Maximum weight capacity: Outboard boats.

Code of Federal Regulations, 2011 CFR

2011-07-01

... boats. 183.35 Section 183.35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.35 Maximum weight capacity: Outboard boats. (a) The maximum weight capacity marked on a boat that is designed or intended to...

33 CFR 183.35 - Maximum weight capacity: Outboard boats.

Code of Federal Regulations, 2010 CFR

2010-07-01

... boats. 183.35 Section 183.35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.35 Maximum weight capacity: Outboard boats. (a) The maximum weight capacity marked on a boat that is designed or intended to...

33 CFR 183.33 - Maximum weight capacity: Inboard and inboard-outdrive boats.

Code of Federal Regulations, 2013 CFR

2013-07-01

... and inboard-outdrive boats. 183.33 Section 183.33 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.33 Maximum weight capacity: Inboard and inboard-outdrive boats. (a) The maximum weight capacity (W...

33 CFR 183.35 - Maximum weight capacity: Outboard boats.

Code of Federal Regulations, 2013 CFR

2013-07-01

... boats. 183.35 Section 183.35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.35 Maximum weight capacity: Outboard boats. (a) The maximum weight capacity marked on a boat that is designed or intended to...

[The working environment control of anhydride hardeners from an epoxy resin system].

PubMed

Matsumoto, Naomi; Yokota, Kozo; Johyama, Yasushi; Takakura, Toshiyuki

2003-07-01

Epoxy resins are widely used in adhesives, coatings, materials for molds and composites, and encapsulation. Acid anhydrides such as methyltetrahydrophthalic anhydride are being used as curing agents for epoxy resins. The anhydride hardeners are well-known industrial inhalant allergens, inducing predominantly type I allergies. In the electronic components industry, these substances have been consumed in large quantities. Therefore, safe use in the industry demands control of the levels of exposure causing allergic diseases in the workshop. We conducted a prospective survey of two electronics plants to clarify how to control the atmospheric level of the anhydrides in the work environment. Measurements of the levels of the anhydrides in air started according to the Working Environment Measurement Standards (Ministry of Labour Notification No. 46, 1976) in April 2000, along with improvements in the work environment. A value of 40 micrograms/m3 was adopted as the administrative control level to judge the propriety of the working environment control. A total of 2 unit work areas in both plants belonged to Control Class III. The exposure originated from manual loading, casting, uncured hot resins, and leaks in an impregnating-machine or curing ovens. In order to achieve the working environment control, complete enclosure of the source, installation of local exhaust ventilation, and improvement or maintenance of the local exhaust ventilation system were performed on the basis of the results of the working environment measurement, with the result that the work environment was improved (Control Class I). It became evident that these measures were effective just like other noxious substances.

Composite Overwrapped Pressure Vessels: Database Extension Task 3.0 and Impact Damage Effects Control Task 8.0

NASA Technical Reports Server (NTRS)

Beeson, Harold D.; Davis, Dennis D.; Ross, William L., Sr.; Tapphorn, Ralph M.

2002-01-01

This document represents efforts accomplished at the NASA Johnson Space Center White Sands Test Facility (WSTF) in support of the Enhanced Technology for Composite Overwrapped Pressure Vessels (COPV) Program, a joint research and technology effort among the U.S. Air Force, NASA, and the Aerospace Corporation. WSTF performed testing for several facets of the program. Testing that contributed to the Task 3.0 COPV database extension objective included baseline structural strength, failure mode and safe-life, impact damage tolerance, sustained load/impact effect, and materials compatibility. WSTF was also responsible for establishing impact protection and control requirements under Task 8.0 of the program. This included developing a methodology for establishing an impact control plan. Seven test reports detail the work done at WSTF. As such, this document contributes to the database of information regarding COPV behavior that will ensure performance benefits and safety are maintained throughout vessel service life.

Some aspects of strategies and solutions in accident prevention.

PubMed

Häkkinen, K

1983-04-01

Accident prevention measures are traditionally classified into technical, organizational and behavioral solutions. A review of some commonly used strategies for accident prevention illustrates some discrepancies between different approaches and the need to develop more comprehensive strategies. Several factors, including protective efficiency and disadvantages at work, must be taken into account when the solutions are evaluated. Some solutions to prevent load disengagement from cranes were evaluated. Measurements of the pressing force showed that the efficiency of the safety latch of a clamp for plate lifting is inadequate to provide protection under all exceptional lifting conditions and in all situations for which the safety latch is intended. The delay caused by the attachment of a lifting hook equipped with a safety latch was measured. The handling of some of the most reliable and technically safe latches requires additional operations and thereby limits their practical application.

Wind Turbine Contingency Control Through Generator De-Rating

NASA Technical Reports Server (NTRS)

Frost, Susan; Goebel, Kai; Balas, Mark

2013-01-01

Maximizing turbine up-time and reducing maintenance costs are key technology drivers for wind turbine operators. Components within wind turbines are subject to considerable stresses due to unpredictable environmental conditions resulting from rapidly changing local dynamics. In that context, systems health management has the aim to assess the state-of-health of components within a wind turbine, to estimate remaining life, and to aid in autonomous decision-making to minimize damage to the turbine. Advanced contingency control is one way to enable autonomous decision-making by providing the mechanism to enable safe and efficient turbine operation. The work reported herein explores the integration of condition monitoring of wind turbines with contingency control to balance the trade-offs between maintaining system health and energy capture. The contingency control involves de-rating the generator operating point to achieve reduced loads on the wind turbine. Results are demonstrated using a high fidelity simulator of a utility-scale wind turbine.

Strengthing of Beams and Columns using GFRP Bars

NASA Astrophysics Data System (ADS)

Nayak, C. B.; Tade, M. K.; Thakare, S. B., Dr.

2017-08-01

Nowadays infrastructure development is raising its pace. Many reinforced high concrete and masonry buildings are constructed annually around the globe. There are large numbers of structures which deteriorate or become unsafe to use because of changes in use, changes in loading condition, change in the design configuration, inferior building material used or natural calamities. Thus repairing and retrofitting of these structures for safe usage of has a great market. There are several situations in which a civil structure would require strengthening due to lack of strength, stiffness, ductility and durability. Beams, columns may be strengthened in flexure by using GFRP in tension zone. In this present work comparative study will be made with and without GFRP circular bars in a beam and column. An experiment study will be carried out to study the change in the structural behavior of beams & columns with GFRP circular bars of different thickness, varying span to depth ratio.

Curiosity's Autonomous Surface Safing Behavior Design

NASA Technical Reports Server (NTRS)

Neilson, Tracy A.; Manning, Robert M.

2013-01-01

The safing routines on all robotic deep-space vehicles are designed to put the vehicle in a power and thermally safe configuration, enabling communication with the mission operators on Earth. Achieving this goal is made a little more difficult on Curiosity because the power requirements for the core avionics and the telecommunication equipment exceed the capability of the single power source, the Multi-Mission Radioisotope Thermoelectric Generator. This drove the system design to create an operational mode, called "sleep mode", where the vehicle turns off most of the loads in order to charge the two Li-ion batteries. The system must keep the vehicle safe from over-heat and under-heat conditions, battery cell failures, under-voltage conditions, and clock failures, both while the computer is running and while the system is sleeping. The other goal of a safing routine is to communicate. On most spacecraft, this simply involves turning on the receiver and transmitter continuously. For Curiosity, Earth is above the horizon only a part of the day for direct communication to the Earth, and the orbiter overpass opportunities only occur a few times a day. The design must robustly place the Rover in a communicable condition at the correct time. This paper discusses Curiosity's autonomous safing behavior and describes how the vehicle remains power and thermally safe while sleeping, as well as a description of how the Rover communicates with the orbiters and Earth at specific times.

Working memory load predicts visual search efficiency: Evidence from a novel pupillary response paradigm.

PubMed

Attar, Nada; Schneps, Matthew H; Pomplun, Marc

2016-10-01

An observer's pupil dilates and constricts in response to variables such as ambient and focal luminance, cognitive effort, the emotional stimulus content, and working memory load. The pupil's memory load response is of particular interest, as it might be used for estimating observers' memory load while they are performing a complex task, without adding an interruptive and confounding memory test to the protocol. One important task in which working memory's involvement is still being debated is visual search, and indeed a previous experiment by Porter, Troscianko, and Gilchrist (Quarterly Journal of Experimental Psychology, 60, 211-229, 2007) analyzed observers' pupil sizes during search to study this issue. These authors found that pupil size increased over the course of the search, and they attributed this finding to accumulating working memory load. However, since the pupil response is slow and does not depend on memory load alone, this conclusion is rather speculative. In the present study, we estimated working memory load in visual search during the presentation of intermittent fixation screens, thought to induce a low, stable level of arousal and cognitive effort. Using standard visual search and control tasks, we showed that this paradigm reduces the influence of non-memory-related factors on pupil size. Furthermore, we found an early increase in working memory load to be associated with more efficient search, indicating a significant role of working memory in the search process.

Galantamine-loaded PLGA nanoparticles, from nano-emulsion templating, as novel advanced drug delivery systems to treat neurodegenerative diseases

NASA Astrophysics Data System (ADS)

Fornaguera, C.; Feiner-Gracia, N.; Calderó, G.; García-Celma, M. J.; Solans, C.

2015-07-01

Polymeric nanoparticles could be promising drug delivery systems to treat neurodegenerative diseases. Among the various methods of nanoparticle preparation, nano-emulsion templating was used in the present study to prepare galantamine-loaded nano-emulsions by a low-energy emulsification method followed by solvent evaporation to obtain galantamine-loaded polymeric nanoparticles. This approach was found to be suitable because biocompatible, biodegradable and safe nanoparticles with appropriate features (hydrodynamic radii around 20 nm, negative surface charge and stability higher than 3 months) for their intravenous administration were obtained. Encapsulation efficiencies higher than 90 wt% were obtained with a sustained drug release profile as compared to that from aqueous and micellar solutions. The enzymatic activity of the drug was maintained at 80% after its encapsulation into nanoparticles that were non-cytotoxic at the required therapeutic concentration. Therefore, novel galantamine-loaded polymeric nanoparticles have been designed for the first time using the nano-emulsification approach and showed the appropriate features to become advanced drug delivery systems to treat neurodegenerative diseases.Polymeric nanoparticles could be promising drug delivery systems to treat neurodegenerative diseases. Among the various methods of nanoparticle preparation, nano-emulsion templating was used in the present study to prepare galantamine-loaded nano-emulsions by a low-energy emulsification method followed by solvent evaporation to obtain galantamine-loaded polymeric nanoparticles. This approach was found to be suitable because biocompatible, biodegradable and safe nanoparticles with appropriate features (hydrodynamic radii around 20 nm, negative surface charge and stability higher than 3 months) for their intravenous administration were obtained. Encapsulation efficiencies higher than 90 wt% were obtained with a sustained drug release profile as compared to that from aqueous and micellar solutions. The enzymatic activity of the drug was maintained at 80% after its encapsulation into nanoparticles that were non-cytotoxic at the required therapeutic concentration. Therefore, novel galantamine-loaded polymeric nanoparticles have been designed for the first time using the nano-emulsification approach and showed the appropriate features to become advanced drug delivery systems to treat neurodegenerative diseases. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr03474d

Core Values | NREL

Science.gov Websites

Core Values Core Values NREL's core values are rooted in a safe and supportive work environment guide our everyday actions and efforts: Safe and supportive work environment Respect for the rights physical and social environment Integrity Maintain the highest standard of ethics, honesty, and integrity

The analysis of dynamic characteristics and wind-induced displacement response of space Beam String Structure

NASA Astrophysics Data System (ADS)

Chen, Yong Jian; Feng, Zhen Fa; Qi, Ai; Huang, Ying

2018-06-01

The Beam String Structure structural system, also called BSS, has the advantages of lighter dead weight and greater flexibility. The wind load is the main design control factor. The dynamic characteristics and wind-induced displacement response of BSS are studied by the finite element method. The roof structure of the stadium roof of the Fuzhou Olympic Sports Center is the engineering background. 1)The numerical model was built by ANSYS, by shape finding, determine the initial stress state of structural members such as external cables; 2)From the analysis of dynamic characteristics, the main mode of vibration is the vibration of cables; 3)The wind speed spectrum of MATLAB generation structure is obtained by AR method, the structural response of the structure under static wind load and fluctuating wind load is calculated. From the analysis result, considering the equivalent static wind load of BSS , the design of adverse wind is not safe, and the fluctuating wind load should be taken into account.

Arkansas People Participating in Lead Education (APPLE): results of a lead-safe training program.

PubMed

Ferguson, Alesia; Bursac, Zoran; Kern, David F

2011-06-01

Lead is still seen as one of the most harmful environmental toxins for young children, with the predominant source being deteriorating lead-based paint. Those at continued risk include those living in homes built before 1978, renovators and remodelers, and especially those with limited access to proper healthcare and diets. Proper training on lead-safe work practices focused on preventing and reducing the spread of lead dust can help reduce lead exposure. Presented in this paper are experiences in delivering lead-safe work practices training in six Arkansas cities, and results from pre- and post- surveys delivered before and immediately after the training. Pre- and post-surveys assess strong and weak areas of training. Participants demonstrated positive shifts in attitude and behavior towards lead-safe work practices following training. However, our research found that more emphasis should be focused on clarifying current lead exposure sources and routes for children.

Load Composition Model Workflow (BPA TIP-371 Deliverable 1A)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chassin, David P.; Cezar, Gustavo V.

This project is funded under Bonneville Power Administration (BPA) Strategic Partnership Project (SPP) 17-005 between BPA and SLAC National Accelerator Laboratory. The project in a BPA Technology Improvement Project (TIP) that builds on and validates the Composite Load Model developed by the Western Electric Coordinating Council's (WECC) Load Modeling Task Force (LMTF). The composite load model is used by the WECC Modeling and Validation Work Group to study the stability and security of the western electricity interconnection. The work includes development of load composition data sets, collection of load disturbance data, and model development and validation. This work supports reliablemore » and economic operation of the power system. This report was produced for Deliverable 1A of the BPA TIP-371 Project entitled \\TIP 371: Advancing the Load Composition Model". The deliverable documents the proposed work ow for the Composite Load Model, which provides the basis for the instrumentation, data acquisition, analysis and data dissemination activities addressed by later phases of the project.« less

High sensitive FBG load cell for icing of overhead transmission lines

NASA Astrophysics Data System (ADS)

Mao, Naiqiang; Ma, Guoming; Li, Chengrong; Li, Yabo; Shi, Cheng; Du, Yue

2017-04-01

Heavy ice coating of overhead transmission lines created the serious threat on the safe operation of power grid. The measurement of conductor icing had been an effective and reliable methods to prevent potential risks, such as conductor breakage, insulator flashover and tower collapse. Because of the advantages of immunity to electromagnetic interference and no demand for power supply in site, the optical load cell has been widely applied in monitoring the ice coating of overhead transmission lines. In this paper, we have adopted the shearing structure with additional grooves as elastic element of load cell to detect the eccentric load. Then, two welding package fiber Bragg gratings (FBGs) were mounted onto the grooves of elastic element with a direction deviation of 90° to eliminate temperature effects on strain measurement without extra FBG. After that, to avoid the occurrence of load cell breakage in heavy load measurement, the protection part has been proposed and added to the elastic element. The results of tension experiments indicate that the resolution of the load cell is 7.78 N in the conventional measuring range (0-10 kN). And in addition, the load cell proposed in this paper also has a good performance in actual experiment in which the load and temperature change simultaneously.

Telemetry and control system for interplatform crude loading at the Statfjord Field

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malmin, P.C.; Lassa, P.

1986-01-01

A control system for crude loading to tankers at the Statfjord field has been designed by Mobil Exploration Norway Inc. The objective of the interplatform crude tieline and control system was to allow tanker loading to take place at all times in order to prevent production shutdowns due to loading buoy problems. The control system has been designed to maximize the flexibility of loading operations and meet all safety and regulatory requirements. This paper discusses the design criteria for the crude tieline control system, and describes how these were met by utilizing fail safe telemetry equipment, hardwired permissive relay logicmore » and programmable logic controllers (PLC's). The experience gained from more than three years of operation of the system is reviewed. The system has allowed maximum use of total field storage capacity while loading crude to 125000 DWT tankers nearly every day throughout the year. It has been possible to maintain a high production rate event through periods of difficult weather conditions as experienced in the northern North Sea.« less

Influence of multi-cycle loading on the structure and mechanics of marine mussel plaques.

PubMed

Wilhelm, Menaka H; Filippidi, Emmanouela; Waite, J Herbert; Valentine, Megan T

2017-10-18

The proteinaceous byssal plaque-thread structures created by marine mussels exhibit extraordinary load-bearing capability. Although the nanoscopic protein interactions that support interfacial adhesion are increasingly understood, major mechanistic questions about how mussel plaques maintain toughness on supramolecular scales remain unanswered. This study explores the mechanical properties of whole mussel plaques subjected to repetitive loading cycles, with varied recovery times. Mechanical measurements were complemented with scanning electron microscopy to investigate strain-induced structural changes after yield. Multicyclic loading of plaques decreases their low-strain stiffness and introduces irreversible, strain-dependent plastic damage within the plaque microstructure. However, strain history does not compromise critical strength or maximum extension compared with plaques monotonically loaded to failure. These results suggest that a multiplicity of force transfer mechanisms between the thread and plaque-substrate interface allow the plaque-thread structure to accommodate a wide range of extensions as it continues to bear load. This improved understanding of the mussel system at micron-to-millimeter lengthscales offers strategies for including similar fail-safe mechanisms in the design of soft, tough and resilient synthetic structures.

30 CFR 77.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Fail safe ground check circuits on high-voltage... WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803 Fail safe ground check..., resistance grounded systems shall include a fail safe ground check circuit or other no less effective device...

30 CFR 77.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fail safe ground check circuits on high-voltage... WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803 Fail safe ground check..., resistance grounded systems shall include a fail safe ground check circuit or other no less effective device...

30 CFR 77.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Fail safe ground check circuits on high-voltage... WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803 Fail safe ground check..., resistance grounded systems shall include a fail safe ground check circuit or other no less effective device...

30 CFR 77.803 - Fail safe ground check circuits on high-voltage resistance grounded systems.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Fail safe ground check circuits on high-voltage... WORK AREAS OF UNDERGROUND COAL MINES Surface High-Voltage Distribution § 77.803 Fail safe ground check..., resistance grounded systems shall include a fail safe ground check circuit or other no less effective device...

Getting Home Safe and Sound: Occupational Safety and Health Administration at 38

PubMed Central

Silverstein, Michael

2008-01-01

The Occupational Safety and Health Act of 1970 (OSHAct) declared that every worker is entitled to safe and healthful working conditions, and that employers are responsible for work being free from all recognized hazards. Thirty-eight years after these assurances, however, it is difficult to find anyone who believes the promise of the OSHAct has been met. The persistence of preventable, life-threatening hazards at work is a failure to keep a national promise. I review the history of the Occupational Safety and Health Administration and propose measures to better ensure that those who go to work every day return home safe and sound. These measures fall into 6 areas: leverage and accountability, safety and health systems, employee rights, equal protection, framing, and infrastructure. PMID:18235060

Getting home safe and sound: occupational safety and health administration at 38.

PubMed

Silverstein, Michael

2008-03-01

The Occupational Safety and Health Act of 1970 (OSHAct) declared that every worker is entitled to safe and healthful working conditions, and that employers are responsible for work being free from all recognized hazards. Thirty-eight years after these assurances, however, it is difficult to find anyone who believes the promise of the OSHAct has been met. The persistence of preventable, life-threatening hazards at work is a failure to keep a national promise. I review the history of the Occupational Safety and Health Administration and propose measures to better ensure that those who go to work every day return home safe and sound. These measures fall into 6 areas: leverage and accountability, safety and health systems, employee rights, equal protection, framing, and infrastructure.

46 CFR 109.525 - Cranes: Working loads.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 4 2011-10-01 2011-10-01 false Cranes: Working loads. 109.525 Section 109.525 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Cranes § 109.525 Cranes: Working loads. The master or person in charge shall ensure that tables...

46 CFR 109.525 - Cranes: Working loads.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 4 2014-10-01 2014-10-01 false Cranes: Working loads. 109.525 Section 109.525 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Cranes § 109.525 Cranes: Working loads. The master or person in charge shall ensure that tables...

46 CFR 109.525 - Cranes: Working loads.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 4 2013-10-01 2013-10-01 false Cranes: Working loads. 109.525 Section 109.525 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Cranes § 109.525 Cranes: Working loads. The master or person in charge shall ensure that tables...

46 CFR 109.525 - Cranes: Working loads.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Cranes: Working loads. 109.525 Section 109.525 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Cranes § 109.525 Cranes: Working loads. The master or person in charge shall ensure that tables...

46 CFR 109.525 - Cranes: Working loads.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 4 2012-10-01 2012-10-01 false Cranes: Working loads. 109.525 Section 109.525 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Cranes § 109.525 Cranes: Working loads. The master or person in charge shall ensure that tables...

[Information value of "additional tasks" method to evaluate pilot's work load].

PubMed

Gorbunov, V V

2005-01-01

"Additional task" method was used to evaluate pilot's work load in prolonged flight. Calculated through durations of latent periods of motor responses, quantitative criterion of work load is more informative for objective evaluation of pilot's involvement in his piloting functions rather than of other registered parameters.

Stress and Performance: Effects of Subjective Work Load and Time Urgency.

ERIC Educational Resources Information Center

Friend, Kenneth E.

1982-01-01

Measured subjective work load, time urgency, and other stress/motivation variables for management personnel taking a demanding problem-solving exam. Data suggest increases in psychological stresses like subjectively high work load and time urgency uniformly impair performance across the whole range of these variables. (Author)

EMS providers' perceptions of safety climate and adherence to safe work practices.

PubMed

Eliseo, Laura J; Murray, Kate A; White, Laura F; Dyer, Sophia; Mitchell, Patricia A; Fernandez, William G

2012-01-01

Occupational injuries are an important source of morbidity for emergency medical services (EMS) providers. Previous work has shown that employee perceptions of an organization's commitment to safety (i.e., safety climate) correlate with adherence to safe practices. To assess the association between perceived safety climate and compliance with safety procedures in an urban EMS system with >100,000 calls/year. EMS providers were issued a self-administered survey that included questions on demographics, years of experience, perceived safety climate, and adherence to safety procedures. Safety climate was assessed with a 20-item validated instrument. Adherence to safety procedures was assessed with a nine-item list of safety behaviors. Strict adherence to safety procedures was defined as endorsing "agree" or "strongly agree" on 80% of items. The effect of safety climate on compliance with safe practices was estimated using multiple logistic regression. One hundred ninety-six of 221 providers (89%) completed surveys; 74% were male; the median age was 36-40 years; and the median amount of experience was 8 years. One hundred twenty-seven of 196 respondents (65%) reported strict adherence to safe work practice. Factor analysis confirmed the original six-factor grouping of questions; frequent safety-related feedback/training was significantly associated with safe practices (odds ratio [OR] = 2.14, 95% confidence interval [CI] = 1.01-4.51). EMS workers perceiving a high degree of perceived safety climate was associated with twofold greater odds of self-reported level of strict adherence to safe work practices. Frequent safety-related feedback/training was the one dimension of safety climate that had the strongest association with adherence to safe workplace behaviors.

Space Station and Shuttle Payloads: Rack Insertion Device Pneumatic Assembly Setup and Test

NASA Technical Reports Server (NTRS)

Conde, Nathan

2007-01-01

As part of my KSC summer internship, I was given the very cool task of writing a test preparation sheet (TPS). A TPS is a set of instructions for certain procedures or tasks, and serves as the documentation for the tasks. TPSs guide task leaders and technicians throughout the work procedures, safely, informing them of what steps will be hazardous, what precautions must be taken, and what to do in the case of an accident or emergency. I was placed in Boeing's Resupply & Return Division (R&R). R&R is responsible for sending up food and supplies to the International Space Station (ISS) with the use of three Italian Multi Purpose Logistics Modules - Leonardo, Donatello, and Raffaello. The supplies are loaded into Resupply Stowage Racks (RSRs) or Resupply Stowage Platforms (RSPs) (though, both are usually referred to as racks), depending on their size and shape. These racks are loaded into the modules with the help of a specialized crane known as the Rack Insertion Device (RID). The RID rests on four pneumatic air jacks, these allow for an operator to raise or lower the RID. The pneumatic air system supplies the air jacks with the necessary air pressure required to lift the RID.

Parametric Structural Model for a Mars Entry Concept

NASA Technical Reports Server (NTRS)

Lane, Brittney M.; Ahmed, Samee W.

2017-01-01

This paper outlines the process of developing a parametric model for a vehicle that can withstand Earth launch and Mars entry conditions. This model allows the user to change a variety of parameters ranging from dimensions and meshing to materials and atmospheric entry angles to perform finite element analysis on the model for the specified load cases. While this work focuses on an aeroshell for Earth launch aboard the Space Launch System (SLS) and Mars entry, the model can be applied to different vehicles and destinations. This specific project derived from the need to deliver large payloads to Mars efficiently, safely, and cheaply. Doing so requires minimizing the structural mass of the body as much as possible. The code developed for this project allows for dozens of cases to be run with the single click of a button. The end result of the parametric model gives the user a sense of how the body reacts under different loading cases so that it can be optimized for its purpose. The data are reported in this paper and can provide engineers with a good understanding of the model and valuable information for improving the design of the vehicle. In addition, conclusions show that the frequency analysis drives the design and suggestions are made to reduce the significance of normal modes in the design.

Release of inattentional blindness by high working memory load: elucidating the relationship between working memory and selective attention.

PubMed

de Fockert, Jan W; Bremner, Andrew J

2011-12-01

An unexpected stimulus often remains unnoticed if attention is focused elsewhere. This inattentional blindness has been shown to be increased under conditions of high memory load. Here we show that increasing working memory load can also have the opposite effect of reducing inattentional blindness (i.e., improving stimulus detection) if stimulus detection is competing for attention with a concurrent visual task. Participants were required to judge which of two lines was the longer while holding in working memory either one digit (low load) or six digits (high load). An unexpected visual stimulus was presented once alongside the line judgment task. Detection of the unexpected stimulus was significantly improved under conditions of higher working memory load. This improvement in performance prompts the striking conclusion that an effect of cognitive load is to increase attentional spread, thereby enhancing our ability to detect perceptual stimuli to which we would normally be inattentionally blind under less taxing cognitive conditions. We discuss the implications of these findings for our understanding of the relationship between working memory and selective attention. Copyright © 2011 Elsevier B.V. All rights reserved.

Structural design and performance of a rear support walking frame.

PubMed

Woollam, P J; Miller, K; McLeod, N; Batty, D; Stallard, J

2002-01-01

Rear support walking frames provide predetermined vertical support for patients with dysfunctional lower limbs that have limited active control; the support is provided through a spring-loaded boom hinged on an upright stanchion mounted at the rear of a wheeled frame within which the patient ambulates. The application of these frames for total-body-involved cerebral palsy patients, in combination with a walking orthosis, has highlighted a number of practical problems that need to be addressed for the system to become fully viable. A composite material prototype walking frame has been developed that permits the patient to be transferred by a single carer without the need to use inappropriate manual handling techniques. The frame has improved structural properties, with stiffness in the sagittal and coronal planes increasing by between 50 and 100 per cent. Evaluation with patients showed that the greater structural stiffness permitted the objective of improved continuity of walking to be achieved. The strength of the frame is such that it can accommodate patients of up to 80 kg, more than twice that possible in the earlier system. Since the structural yield point is approximately twice the maximum working load, the device should not be prone to unacceptable fatigue characteristics. Despite the use of carbon composite materials (which have brittle failure characteristics), the mode of failure is of progressive collapse and is therefore inherently safe. The successful outcome of prototype testing has justified production development. Work is now proceeding on a design that incorporates further improvements in structural performance and ease of manufacture.

[Necessary changes for advancing nursing as caring science].

PubMed

de Pires, Denise Elvira Pires

2013-09-01

The article aimed to reflect upon the challenges involved in strengthening Nursing as a caring science. It is founded on the sociological theory, connecting three approaches: the historical-dialectic materialism perspective about the working process in health care and nursing; the sociology of professions from a critical perspective; and the philosophy of science. The discussion is organized considering the aspects of Nursing as a discipline, work and health care profession. It sustains that knowledge production should be driven both by the purpose of Nursing work which is providing care to human beings with health needs and to advocate for the indispensable work conditions to a safe and responsible practice. It concludes that to strengthening Nursing it is necessary to produce knowledge to support nursing care and the political actions defending safe work conditions, the universal right to health as well safe and high quality care.

Fire and scald burn risks in urban communities: who is at risk and what do they believe about home safety?

PubMed

Parker, E M; Gielen, A C; McDonald, E M; Shields, W C; Trump, A R; Koon, K M; Jones, V

2013-08-01

While largely preventable, fire and hot water-related injuries are common in the United States. Measures recommended to reduce these injuries are smoke alarms (SAs) and lowered hot water temperatures. This study aims to: (i) describe the prevalence of working SAs and safe water temperatures among low-income, urban communities and (ii) explore the relationship between these behaviors and individuals' knowledge and beliefs about them. In this cross-sectional study, the Health Belief Model was used as a guide for understanding the safety behaviors. A total of 603 households had their SAs and hot tap water temperatures tested and were surveyed about their knowledge and beliefs related to these safety behaviors. We found that 40% of households had working SAs on every level and 57% had safe hot water temperatures. Perceived severity and self-efficacy were significantly associated with SA coverage, whereas perceived susceptibility and beliefs about benefits were significantly associated with safe hot water temperatures. This study demonstrates the need to increase the number of homes with working SAs and safe hot water temperatures. Messages focused on a safe home environment could communicate the ease and harm reduction features of SAs and benefits and risk reduction features of safe hot water temperatures.

Fire and scald burn risks in urban communities: who is at risk and what do they believe about home safety?

PubMed Central

Parker, E. M.; Gielen, A. C.; McDonald, E. M.; Shields, W. C.; Trump, A. R.; Koon, K. M.; Jones, V.

2013-01-01

While largely preventable, fire and hot water-related injuries are common in the United States. Measures recommended to reduce these injuries are smoke alarms (SAs) and lowered hot water temperatures. This study aims to: (i) describe the prevalence of working SAs and safe water temperatures among low-income, urban communities and (ii) explore the relationship between these behaviors and individuals’ knowledge and beliefs about them. In this cross-sectional study, the Health Belief Model was used as a guide for understanding the safety behaviors. A total of 603 households had their SAs and hot tap water temperatures tested and were surveyed about their knowledge and beliefs related to these safety behaviors. We found that 40% of households had working SAs on every level and 57% had safe hot water temperatures. Perceived severity and self-efficacy were significantly associated with SA coverage, whereas perceived susceptibility and beliefs about benefits were significantly associated with safe hot water temperatures. This study demonstrates the need to increase the number of homes with working SAs and safe hot water temperatures. Messages focused on a safe home environment could communicate the ease and harm reduction features of SAs and benefits and risk reduction features of safe hot water temperatures. PMID:23487557

Effects of load on the guidance of visual attention from working memory.

PubMed

Zhang, Bao; Zhang, John X; Huang, Sai; Kong, Lingyue; Wang, Suiping

2011-12-08

An active recent line of research on working memory and attention has shown that the visual attention can be top-down guided by working memory contents. The present study examined whether the guidance effect is modulated by memory load, i.e., the amount of information maintained in working memory. In a set of three experiments, participants were asked to perform a visual search task while maintaining several objects in working memory. The memory-driven attentional guidance effect was observed in all experiments when there were spare working memory resources. When memory load was increased from one item to two items, there was no sign that the guidance effect was attenuated. When load was further increased to four items, the guidance effect disappeared completely, indicating a clear impact of memory load on attentional guidance. Copyright © 2011 Elsevier Ltd. All rights reserved.

Experimental validation of new empirical models of the thermal properties of food products for safe shipping

NASA Astrophysics Data System (ADS)

Hamid, Hanan H.; Mitchell, Mark; Jahangiri, Amirreza; Thiel, David V.

2018-04-01

Temperature controlled food transport is essential for human safety and to minimise food waste. The thermal properties of food are important for determining the heat transfer during the transient stages of transportation (door opening during loading and unloading processes). For example, the temperature of most dairy products must be confined to a very narrow range (3-7 °C). If a predefined critical temperature is exceeded, the food is defined as spoiled and unfit for human consumption. An improved empirical model for the thermal conductivity and specific heat capacity of a wide range of food products was derived based on the food composition (moisture, fat, protein, carbohydrate and ash). The models that developed using linear regression analysis were compared with the published measured parameters in addition to previously published theoretical and empirical models. It was found that the maximum variation in the predicated thermal properties leads to less than 0.3 °C temperature change. The correlation coefficient for these models was 0.96. The t-Stat test ( P-value >0.99) demonstrated that the model results are an improvement on previous works. The transient heat transfer based on the food composition and the temperature boundary conditions was found for a Camembert cheese (short cylindrical shape) using a multiple dimension finite difference method code. The result was verified using the heat transfer today (HTT) educational software which is based on finite volume method. The core temperature rises from the initial temperature (2.7 °C) to the maximum safe temperature in ambient air (20.24 °C) was predicted to within about 35.4 ± 0.5 min. The simulation results agree very well ( +0.2 °C) with the measured temperature data. This improved model impacts on temperature estimation during loading and unloading the trucks and provides a clear direction for temperature control in all refrigerated transport applications.

Physical work load and psychological stress of daily activities as predictors of disability pension due to musculoskeletal disorders.

PubMed

Ropponen, Annina; Svedberg, Pia; Koskenvuo, Markku; Silventoinen, Karri; Kaprio, Jaakko

2014-06-01

Physical work loading and psychological stress commonly co-occur in working life, hence potentially having an interrelationship that may affect work incapacity. This prospective cohort study aimed to investigate the effect of stability and change in physical work loading and stress on the risk of disability pension (DP) due to musculoskeletal diagnoses (MSD), while accounting for familial confounding in these associations. Data on 12,455 twins born before 1958 were surveyed of their physical work loading and psychological stress of daily activities in 1975 and 1981. The follow-up data was collected from pension registers until 2004. Cox proportional hazards regression models were used. During the follow up, 893 participants were granted DP due to MSD. Stable high (hazard ratio, HR, 2.21), but also increased physical work loading (HR 2.05) and high psychological stress (HR 2.22) were associated with increased risk for DP, and had significant interaction (p=0.032). The associations were confirmed when accounting for several confounding factors. Stable high but also increased physical work loading and psychological stress of daily activities between two timepoints with 6 years apart confirms their predictive role for an increased risk of DP. Both physical work loading and psychological stress seem to be independent from various confounding factors hence suggesting direct effect on risk for DP providing potential for occupational health care to early identification of persons at risk. © 2014 the Nordic Societies of Public Health.

Codified Knowledge and Embodied Learning: The Problem of Safety Training

ERIC Educational Resources Information Center

Somerville, Margaret; Lloyd, Anne

2006-01-01

The research that informs this article was focused around the relationship between how workers are trained to work safely and how workers learn to work safely in the workplace. The findings of empirical studies into learning and practising safety in aged care, fire fighting, building construction, and mining industries are summarized. A common…

Sandia National Laboratories: About Sandia: Leadership

Science.gov Websites

Working With Sandia Working With Sandia Prospective Suppliers What Sandia Looks For In Our Suppliers What provides leadership and management direction for the safe, secure execution of all Sandia missions. View implement the Labs Director's strategic vision for safe, secure operations at Sandia. View full biography

10 CFR 35.396 - Training for the parenteral administration of unsealed byproduct material requiring a written...

Code of Federal Regulations, 2013 CFR

2013-01-01

... radioactivity; (iv) Chemistry of byproduct material for medical use; and (v) Radiation biology; and (2) Has work...). The work experience must involve— (i) Ordering, receiving, and unpacking radioactive materials safely... meters; (iii) Calculating, measuring, and safely preparing patient or human research subject dosages; (iv...

10 CFR 35.396 - Training for the parenteral administration of unsealed byproduct material requiring a written...

Code of Federal Regulations, 2014 CFR

2014-01-01

... radioactivity; (iv) Chemistry of byproduct material for medical use; and (v) Radiation biology; and (2) Has work...). The work experience must involve— (i) Ordering, receiving, and unpacking radioactive materials safely... meters; (iii) Calculating, measuring, and safely preparing patient or human research subject dosages; (iv...

10 CFR 35.396 - Training for the parenteral administration of unsealed byproduct material requiring a written...

Code of Federal Regulations, 2012 CFR

2012-01-01

... radioactivity; (iv) Chemistry of byproduct material for medical use; and (v) Radiation biology; and (2) Has work...). The work experience must involve— (i) Ordering, receiving, and unpacking radioactive materials safely... meters; (iii) Calculating, measuring, and safely preparing patient or human research subject dosages; (iv...

10 CFR 35.396 - Training for the parenteral administration of unsealed byproduct material requiring a written...

Code of Federal Regulations, 2011 CFR

2011-01-01

... radioactivity; (iv) Chemistry of byproduct material for medical use; and (v) Radiation biology; and (2) Has work...). The work experience must involve— (i) Ordering, receiving, and unpacking radioactive materials safely... meters; (iii) Calculating, measuring, and safely preparing patient or human research subject dosages; (iv...

Compilation of load spectrum of loader drive axle

NASA Astrophysics Data System (ADS)

Wei, Yongxiang; Zhu, Haoyue; Tang, Heng; Yuan, Qunwei

2018-03-01

In order to study the preparation method of gear fatigue load spectrum for loaders, the load signal of four typical working conditions of loader is collected. The signal that reflects the law of load change is obtained by preprocessing the original signal. The torque of the drive axle is calculated by using the rain flow counting method. According to the operating time ratio of each working condition, the two dimensional load spectrum based on the real working conditions of the drive axle of loader is established by the cycle extrapolation and synthesis method. The two-dimensional load spectrum is converted into one-dimensional load spectrum by means of the mean of torque equal damage method. Torque amplification includes the maximum load torque of the main reduction gear. Based on the theory of equal damage, the accelerated cycles are calculated. In this way, the load spectrum of the loading condition of the drive axle is prepared to reflect loading condition of the loader. The load spectrum can provide reference for fatigue life test and life prediction of loader drive axle.

The Role of Cognitive Load in Intentional Forgetting Using the Think/No-Think Task.

PubMed

Noreen, Saima; de Fockert, Jan W

2017-01-01

We investigated the role of cognitive control in intentional forgetting by manipulating working memory load during the think/no-think task. In two experiments, participants learned a series of cue-target word pairs and were asked to recall the target words associated with some cues or to avoid thinking about the target associated with other cues. In addition to this, participants also performed a modified version of the n-back task which required them to respond to the identity of a single target letter present in the currently presented cue word (n = 0 condition, low working memory load), and in either the previous cue word (n = 1 condition, high working memory load, Experiment 1) or the cue word presented two trials previously (n = 2 condition, high working memory load, Experiment 2). Participants' memory for the target words was subsequently tested using same and novel independent probes. In both experiments it was found that although participants were successful at forgetting on both the same and independent-probe tests in the low working memory load condition, they were only successful at forgetting on the same-probe test in the high working memory load condition. We argue that our findings suggest that the high load working memory task diverted attention from direct suppression and acted as an interference-based strategy. Thus, when cognitive resources are limited participants can switch between the strategies they use to prevent unwanted memories from coming to mind.

Working height, block mass and one- vs. two-handed block handling: the contribution to low back and shoulder loading during masonry work.

PubMed

Faber, G S; Kingma, I; Kuijer, P P F M; van der Molen, H F; Hoozemans, M J M; Frings-Dresen, M H W; van Dieën, J H

2009-09-01

The goal of this study was to compare the effects of the task variables block mass, working height and one- vs. two-handed block handling on low back and shoulder loading during masonry work. In a mock-up of a masonry work site, nine masonry workers performed one- and two-handed block-lifting and block-placing tasks at varying heights (ranging from floor to shoulder level) with blocks of varying mass (ranging from 6 to 16 kg). Kinematics and ground reaction forces were measured and used in a 3-D linked segment model to calculate low back and shoulder loading. Increasing lifting height appeared to be the most effective way to reduce low back loading. However, working at shoulder level resulted in relatively high shoulder loading. Therefore, it was recommended to organise masonry work in such a way that blocks are handled with the hands at about iliac crest height as much as possible.

Beth Reis and the Safe Schools Coalition

ERIC Educational Resources Information Center

Vaught, Sabina E.

2007-01-01

This article chronicles the formation and organization of the Safe Schools Coalition (SCC) through the experiences of Beth Reis, co-founder and co-Chair. The article suggests ways in which the SCC can serve as a model for both collective and individual work in promoting safe schools.

78 FR 4324 - Occupational Exposure to Hazardous Chemicals in Laboratories (Non-Mandatory Appendix); Technical...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-01-22

... institutions that sponsor chemical laboratories accountable for providing safe working environments. Beyond... current laboratory practices, security, and emergency response, as well as promoting safe handling of.... Safety and training programs have been implemented to promote the safe handling of chemicals from...

Career Implications of Doctoral Social Work Student Debt Load

ERIC Educational Resources Information Center

Begun, Audrey L.; Carter, James R.

2017-01-01

Although research has been conducted in other professional disciplines, social work has yet to explore how doctoral student debt load influences career development. This exploratory study surveyed 281 social work doctoral students and recent graduates, 75 BSW and MSW program leaders, and 24 doctoral program leaders about debt load, career choices,…

Lessons Learned "Establishing an Electrically Safe Work Condition" Specifically related to Racking Electrical Breakers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martinez, Tommy Robert; Romero, Philbert Roland; Garcia, Samuel Anthony

During low voltage electrical equipment maintenance, a bad breaker was identified. The breaker was racked out from the substation cubicle without following the hazardous energy control process identified in the Integrated Work Document (IWD). The IWD required the substation to be in an electrically safe work condition prior to racking the breaker. Per NFPA 70E requirements, electrical equipment shall be put into an electrically safe work condition before an employee performs work on or interacts with equipment in a manner that increases the likelihood of creating an arc flash. Racking in or out a breaker on an energized bus maymore » increase the likelihood of creating an arc flash dependent on equipment conditions. A thorough risk assessment must be performed prior to performing such a task. The risk assessment determines the risk control measures to be put in place prior to performing the work. Electrical Safety Officers (ESO) can assist in performing risk assessments and incorporating risk control measures.« less

Working Memory Load Affects Processing Time in Spoken Word Recognition: Evidence from Eye-Movements

PubMed Central

Hadar, Britt; Skrzypek, Joshua E.; Wingfield, Arthur; Ben-David, Boaz M.

2016-01-01

In daily life, speech perception is usually accompanied by other tasks that tap into working memory capacity. However, the role of working memory on speech processing is not clear. The goal of this study was to examine how working memory load affects the timeline for spoken word recognition in ideal listening conditions. We used the “visual world” eye-tracking paradigm. The task consisted of spoken instructions referring to one of four objects depicted on a computer monitor (e.g., “point at the candle”). Half of the trials presented a phonological competitor to the target word that either overlapped in the initial syllable (onset) or at the last syllable (offset). Eye movements captured listeners' ability to differentiate the target noun from its depicted phonological competitor (e.g., candy or sandal). We manipulated working memory load by using a digit pre-load task, where participants had to retain either one (low-load) or four (high-load) spoken digits for the duration of a spoken word recognition trial. The data show that the high-load condition delayed real-time target discrimination. Specifically, a four-digit load was sufficient to delay the point of discrimination between the spoken target word and its phonological competitor. Our results emphasize the important role working memory plays in speech perception, even when performed by young adults in ideal listening conditions. PMID:27242424

A cross-sectional study on the relationship of job stress with natural killer cell activity and natural killer cell subsets among healthy nurses.

PubMed

Morikawa, Yuko; Kitaoka-Higashiguchi, Kazuyo; Tanimoto, Chie; Hayashi, Midori; Oketani, Reiko; Miura, Katsuyuki; Nishijo, Muneko; Nakagawa, Hideaki

2005-09-01

The present study investigated the effects of job stress on cellular immune function, such as NK cell activity and NK cell subsets. The participants were 61 female nurses aged 23-59, who worked in a public psychiatric hospital in Ishikawa, Japan. Each subject completed the Nursing Job Stressor Scale (NJSS) and their NK cell activity and lymphocyte surface antigens (CD16+56+) were evaluated as immune system parameters. The NJSS has seven subscales: conflict with other nursing staff, nursing role conflict, conflict with physicians or autonomy, conflict with death or dying, quantitative work load, qualitative work load and conflict with patients. Factors influencing NK cell activity, and the proportion and cell counts of CD16+56+ lymphocytes were evaluated. Increase in quantitative work load significantly decreased NK cell activity. Conversely, no linear relationship was observed between qualitative work load and immunological variables, with the highest percentage of CD16+56+ lymphocytes observed among participants in the medium work load group. The other five NJSS subscales did not relate to immune parameters. In conclusion, the results suggest that perceived job strains, particularly quantitative work load, decreased NK cell function.

Crew Exploration Vehicle Service Module Ascent Abort Coverage

NASA Technical Reports Server (NTRS)

Tedesco, Mark B.; Evans, Bryan M.; Merritt, Deborah S.; Falck, Robert D.

2007-01-01

The Crew Exploration Vehicle (CEV) is required to maintain continuous abort capability from lift off through destination arrival. This requirement is driven by the desire to provide the capability to safely return the crew to Earth after failure scenarios during the various phases of the mission. This paper addresses abort trajectory design considerations, concept of operations and guidance algorithm prototypes for the portion of the ascent trajectory following nominal jettison of the Launch Abort System (LAS) until safe orbit insertion. Factors such as abort system performance, crew load limits, natural environments, crew recovery, and vehicle element disposal were investigated to determine how to achieve continuous vehicle abort capability.

Control Law Design for Propofol Infusion to Regulate Depth of Hypnosis: A Nonlinear Control Strategy

PubMed Central

Khaqan, Ali; Bilal, Muhammad; Ilyas, Muhammad; Ijaz, Bilal; Ali Riaz, Raja

2016-01-01

Maintaining the depth of hypnosis (DOH) during surgery is one of the major objectives of anesthesia infusion system. Continuous administration of Propofol infusion during surgical procedures is essential but increases the undue load of an anesthetist in operating room working in a multitasking setup. Manual and target controlled infusion (TCI) systems are not good at handling instabilities like blood pressure changes and heart rate variability arising due to interpatient variability. Patient safety, large interindividual variability, and less postoperative effects are the main factors to motivate automation in anesthesia. The idea of automated system for Propofol infusion excites the control engineers to come up with a more sophisticated and safe system that handles optimum delivery of drug during surgery and avoids postoperative effects. In contrast to most of the investigations with linear control strategies, the originality of this research work lies in employing a nonlinear control technique, backstepping, to track the desired hypnosis level of patients during surgery. This effort is envisioned to unleash the true capabilities of this nonlinear control technique for anesthesia systems used today in biomedical field. The working of the designed controller is studied on the real dataset of five patients undergoing surgery. The controller tracks the desired hypnosis level within the acceptable range for surgery. PMID:27293475

Control Law Design for Propofol Infusion to Regulate Depth of Hypnosis: A Nonlinear Control Strategy.

PubMed

Khaqan, Ali; Bilal, Muhammad; Ilyas, Muhammad; Ijaz, Bilal; Ali Riaz, Raja

2015-01-01

Maintaining the depth of hypnosis (DOH) during surgery is one of the major objectives of anesthesia infusion system. Continuous administration of Propofol infusion during surgical procedures is essential but increases the undue load of an anesthetist in operating room working in a multitasking setup. Manual and target controlled infusion (TCI) systems are not good at handling instabilities like blood pressure changes and heart rate variability arising due to interpatient variability. Patient safety, large interindividual variability, and less postoperative effects are the main factors to motivate automation in anesthesia. The idea of automated system for Propofol infusion excites the control engineers to come up with a more sophisticated and safe system that handles optimum delivery of drug during surgery and avoids postoperative effects. In contrast to most of the investigations with linear control strategies, the originality of this research work lies in employing a nonlinear control technique, backstepping, to track the desired hypnosis level of patients during surgery. This effort is envisioned to unleash the true capabilities of this nonlinear control technique for anesthesia systems used today in biomedical field. The working of the designed controller is studied on the real dataset of five patients undergoing surgery. The controller tracks the desired hypnosis level within the acceptable range for surgery.

Advanced technologies for scalable ATLAS conditions database access on the grid

NASA Astrophysics Data System (ADS)

Basset, R.; Canali, L.; Dimitrov, G.; Girone, M.; Hawkings, R.; Nevski, P.; Valassi, A.; Vaniachine, A.; Viegas, F.; Walker, R.; Wong, A.

2010-04-01

During massive data reprocessing operations an ATLAS Conditions Database application must support concurrent access from numerous ATLAS data processing jobs running on the Grid. By simulating realistic work-flow, ATLAS database scalability tests provided feedback for Conditions Db software optimization and allowed precise determination of required distributed database resources. In distributed data processing one must take into account the chaotic nature of Grid computing characterized by peak loads, which can be much higher than average access rates. To validate database performance at peak loads, we tested database scalability at very high concurrent jobs rates. This has been achieved through coordinated database stress tests performed in series of ATLAS reprocessing exercises at the Tier-1 sites. The goal of database stress tests is to detect scalability limits of the hardware deployed at the Tier-1 sites, so that the server overload conditions can be safely avoided in a production environment. Our analysis of server performance under stress tests indicates that Conditions Db data access is limited by the disk I/O throughput. An unacceptable side-effect of the disk I/O saturation is a degradation of the WLCG 3D Services that update Conditions Db data at all ten ATLAS Tier-1 sites using the technology of Oracle Streams. To avoid such bottlenecks we prototyped and tested a novel approach for database peak load avoidance in Grid computing. Our approach is based upon the proven idea of pilot job submission on the Grid: instead of the actual query, an ATLAS utility library sends to the database server a pilot query first.

Establishment of design criteria for acceptable failure modes and fail safe considerations for the space shuttle structural system

NASA Technical Reports Server (NTRS)

Westrup, R. W.

1971-01-01

The application of general design approaches for preventing failures due to repeated load cycles is briefly discussed. Program objective, mission requirements, and structural design criteria are summarized. Discrete structural elements and associated sections were selected for detailed strength, fatigue, and fracture mechanics investigations.

29 CFR 500.105 - DOT standards adopted by the Secretary.

Code of Federal Regulations, 2014 CFR

2014-07-01

... person possesses the following minimum qualifications: (A) No loss of foot, leg, hand or arm, (B) No mental, nervous, organic, or functional disease, likely to interfere with safe driving. (C) No loss of... loading—(A) Distribution and securing of load. No motor vehicle shall be driven nor shall any motor...

44 CFR 15.14 - Vehicular and pedestrian traffic.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., DEPARTMENT OF HOMELAND SECURITY GENERAL CONDUCT AT THE MT. WEATHER EMERGENCY ASSISTANCE CENTER AND AT THE... entering or while at Mt. Weather or the NETC must drive carefully and safely at all times and must obey the...) At both Mt. Weather and the NETC we prohibit: (1) Blocking entrances, driveways, walks, loading...

44 CFR 15.14 - Vehicular and pedestrian traffic.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., DEPARTMENT OF HOMELAND SECURITY GENERAL CONDUCT AT THE MT. WEATHER EMERGENCY ASSISTANCE CENTER AND AT THE... entering or while at Mt. Weather or the NETC must drive carefully and safely at all times and must obey the...) At both Mt. Weather and the NETC we prohibit: (1) Blocking entrances, driveways, walks, loading...

44 CFR 15.14 - Vehicular and pedestrian traffic.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., DEPARTMENT OF HOMELAND SECURITY GENERAL CONDUCT AT THE MT. WEATHER EMERGENCY ASSISTANCE CENTER AND AT THE... entering or while at Mt. Weather or the NETC must drive carefully and safely at all times and must obey the...) At both Mt. Weather and the NETC we prohibit: (1) Blocking entrances, driveways, walks, loading...

44 CFR 15.14 - Vehicular and pedestrian traffic.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., DEPARTMENT OF HOMELAND SECURITY GENERAL CONDUCT AT THE MT. WEATHER EMERGENCY ASSISTANCE CENTER AND AT THE... entering or while at Mt. Weather or the NETC must drive carefully and safely at all times and must obey the...) At both Mt. Weather and the NETC we prohibit: (1) Blocking entrances, driveways, walks, loading...

44 CFR 15.14 - Vehicular and pedestrian traffic.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., DEPARTMENT OF HOMELAND SECURITY GENERAL CONDUCT AT THE MT. WEATHER EMERGENCY ASSISTANCE CENTER AND AT THE... entering or while at Mt. Weather or the NETC must drive carefully and safely at all times and must obey the...) At both Mt. Weather and the NETC we prohibit: (1) Blocking entrances, driveways, walks, loading...

33 CFR 183.41 - Persons capacity: Outboard boats.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Persons capacity: Outboard boats... (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.41 Persons capacity: Outboard boats. (a) The persons capacity in pounds marked on a boat that is designed to use one or more outboard...

33 CFR 183.39 - Persons capacity: Inboard and inboard-outdrive boats.

Code of Federal Regulations, 2010 CFR

2010-07-01

... inboard-outdrive boats. 183.39 Section 183.39 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.39 Persons capacity: Inboard and inboard-outdrive boats. (a) The persons capacity in pounds marked on a boat that is...

33 CFR 183.39 - Persons capacity: Inboard and inboard-outdrive boats.

Code of Federal Regulations, 2014 CFR

2014-07-01

... inboard-outdrive boats. 183.39 Section 183.39 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.39 Persons capacity: Inboard and inboard-outdrive boats. (a) The persons capacity in pounds marked on a boat that is...

33 CFR 183.39 - Persons capacity: Inboard and inboard-outdrive boats.

Code of Federal Regulations, 2011 CFR

2011-07-01

... inboard-outdrive boats. 183.39 Section 183.39 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.39 Persons capacity: Inboard and inboard-outdrive boats. (a) The persons capacity in pounds marked on a boat that is...

33 CFR 183.39 - Persons capacity: Inboard and inboard-outdrive boats.

Code of Federal Regulations, 2012 CFR

2012-07-01

... inboard-outdrive boats. 183.39 Section 183.39 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.39 Persons capacity: Inboard and inboard-outdrive boats. (a) The persons capacity in pounds marked on a boat that is...

33 CFR 183.41 - Persons capacity: Outboard boats.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Persons capacity: Outboard boats... (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.41 Persons capacity: Outboard boats. (a) The persons capacity in pounds marked on a boat that is designed to use one or more outboard...

33 CFR 183.41 - Persons capacity: Outboard boats.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Persons capacity: Outboard boats... (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.41 Persons capacity: Outboard boats. (a) The persons capacity in pounds marked on a boat that is designed to use one or more outboard...

33 CFR 183.39 - Persons capacity: Inboard and inboard-outdrive boats.

Code of Federal Regulations, 2013 CFR

2013-07-01

... inboard-outdrive boats. 183.39 Section 183.39 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.39 Persons capacity: Inboard and inboard-outdrive boats. (a) The persons capacity in pounds marked on a boat that is...

33 CFR 183.41 - Persons capacity: Outboard boats.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Persons capacity: Outboard boats... (CONTINUED) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Safe Loading § 183.41 Persons capacity: Outboard boats. (a) The persons capacity in pounds marked on a boat that is designed to use one or more outboard...

Operating instructions, Diborane shipping container DOT special permit no. 6522, volume 3

NASA Technical Reports Server (NTRS)

1972-01-01

A manual is presented to provide instructions and information for safe and efficient use of the 200-pound diborane shipping container. The scope of the manual includes: shipping, receiving, storage, unloading, return, cleanout, and loading. Backup information on container design and performance, diborane information, etc., are also included.

A Cooperative Communication System for the Advancement of Safe, Effective, and Efficient Patient Care

DTIC Science & Technology

2017-02-01

for the ever-changing environment of work that must be successfully navigated. The Cooperative Communication System (CCS) is a Health Information...presented a comprehensive picture of the BICU cognitive work , including synchronization on the BICU, the barriers to safe and effective care that...room spared the need to orient participants to an unfamiliar work setting and made it possible to include environmental factors and cues that a

Work Status, Work Satisfaction, and Blood Pressure Among Married Black and White Women

ERIC Educational Resources Information Center

Hauenstein, Louise S.; And Others

1977-01-01

This study examined blood pressure levels of married women in relation to such work-related variables as work load, satisfaction with work, reported strain, and evaluated performance. Differences in work load were unrelated to blood pressure levels. However, currently unemployed working women had lower levels. (Author)

Cognitive Load Theory: An Empirical Study of Anxiety and Task Performance in Language Learning

ERIC Educational Resources Information Center

Chen, I-Jung; Chang, Chi-Cheng

2009-01-01

Introduction: This study explores the relationship among three variables--cognitive load, foreign language anxiety, and task performance. Cognitive load refers to the load imposed on working memory while performing a particular task. The authors hypothesized that anxiety consumes the resources of working memory, leaving less capacity for cognitive…

Differences among nursing homes in outcomes of a safe resident handling program

PubMed Central

Kurotvski, Alicia; Gore, Rebecca; Buchholz, Bryan; Punnett, Laura

2018-01-01

A large nursing home corporation implemented a safe resident handling program (SRHP) in 2004–2007. We evaluated its efficacy over a 2-year period by examining differences among 5 centers in program outcomes and potential predictors of those differences. We observed nursing assistants (NAs), recording activities and body postures at 60-second intervals on personal digital assistants at baseline and at 3-month, 12-month, and 24-month follow-ups. The two outcomes computed were change in equipment use during resident handling and change in a physical workload index that estimated spinal loading due to body postures and handled loads. Potential explanatory factors were extracted from post-observation interviews, investigator surveys of the workforce, from administrative data, and employee satisfaction surveys. The facility with the most positive outcome measures was associated with many positive changes in explanatory factors and the facility with the fewest positive outcome measures experienced negative changes in the same factors. These findings suggest greater SRHP benefits where there was lower NA turnover and agency staffing; less time pressure; and better teamwork, staff communication, and supervisory support. PMID:22833329

Augmentation of the space station module power management and distribution breadboard

NASA Technical Reports Server (NTRS)

Walls, Bryan; Hall, David K.; Lollar, Louis F.

1991-01-01

The space station module power management and distribution (SSM/PMAD) breadboard models power distribution and management, including scheduling, load prioritization, and a fault detection, identification, and recovery (FDIR) system within a Space Station Freedom habitation or laboratory module. This 120 VDC system is capable of distributing up to 30 kW of power among more than 25 loads. In addition to the power distribution hardware, the system includes computer control through a hierarchy of processes. The lowest level consists of fast, simple (from a computing standpoint) switchgear that is capable of quickly safing the system. At the next level are local load center processors, (LLP's) which execute load scheduling, perform redundant switching, and shed loads which use more than scheduled power. Above the LLP's are three cooperating artificial intelligence (AI) systems which manage load prioritizations, load scheduling, load shedding, and fault recovery and management. Recent upgrades to hardware and modifications to software at both the LLP and AI system levels promise a drastic increase in speed, a significant increase in functionality and reliability, and potential for further examination of advanced automation techniques. The background, SSM/PMAD, interface to the Lewis Research Center test bed, the large autonomous spacecraft electrical power system, and future plans are discussed.

Is less really more: Does a prefrontal efficiency genotype actually confer better performance when working memory becomes difficult?

PubMed

Ihne, Jessica L; Gallagher, Natalie M; Sullivan, Marie; Callicott, Joseph H; Green, Adam E

2016-01-01

Perhaps the most widely studied effect to emerge from the combination of neuroimaging and human genetics is the association of the COMT-Val(108/158)Met polymorphism with prefrontal activity during working memory. COMT-Val is a putative risk factor in schizophrenia, which is characterized by disordered prefrontal function. Work in healthy populations has sought to characterize mechanisms by which the valine (Val) allele may lead to disadvantaged prefrontal cognition. Lower activity in methionine (Met) carriers has been interpreted as advantageous neural efficiency. Notably, however, studies reporting COMT effects on neural efficiency have generally not reported working memory performance effects. Those studies have employed relatively low/easy working memory loads. Higher loads are known to elicit individual differences in working memory performance that are not visible at lower loads. If COMT-Met confers greater neural efficiency when working memory is easy, a reasonable prediction is that Met carriers will be better able to cope with increasing demand for neural resources when working memory becomes difficult. To our knowledge, this prediction has thus far gone untested. Here, we tested performance on three working memory tasks. Performance on each task was measured at multiple levels of load/difficulty, including loads more demanding than those used in prior studies. We found no genotype-by-load interactions or main effects of COMT genotype on accuracy or reaction time. Indeed, even testing for performance differences at each load of each task failed to find a single significant effect of COMT genotype. Thus, even if COMT genotype has the effects on prefrontal efficiency that prior work has suggested, such effects may not directly impact high-load working memory ability. The present findings accord with previous evidence that behavioral effects of COMT are small or nonexistent and, more broadly, with a growing consensus that substantial effects on phenotype will not emerge from candidate gene studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

77 FR 45471 - White House Initiative on Educational Excellence for African Americans

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-01

... safe and healthy environments, and have access to high-level, rigorous course work and support services...-rounded education in safe and healthy environments, as well as access to support services, which will... system. African Americans lack equal access to highly effective teachers and principals, safe schools...

Power variables and bilateral force differences during unloaded and loaded squat jumps in high performance alpine ski racers.

PubMed

Patterson, Carson; Raschner, Christian; Platzer, Hans-Peter

2009-05-01

The purpose of this paper was to investigate the power-load relationship and to compare power variables and bilateral force imbalances between sexes with squat jumps. Twenty men and 17 women, all members of the Austrian alpine ski team (junior and European Cup), performed unloaded and loaded (barbell loads equal to 25, 50, 75, and 100% body weight [BW]) squat jumps with free weights using a specially designed spotting system. Ground reaction force records from 2 force platforms were used to calculate relative average power (P), relative average power in the first 100 ms of the jump (P01), relative average power in the first 200 ms of the jump (P02), jump height, percentage of best jump height (%Jump), and maximal force difference between dominant and nondominant leg (Fmaxdiff). The men displayed significantly higher values at all loads for P and jump height (p < 0.05). No significant differences were found in P01. The men had significantly higher P02 at all loads except 75% BW). Maximum P was reached at light loads (men at 25% BW and women at 0% BW), and P decreased uniformly thereafter. Individual power-load curves show a deflection point. It is proposed that the load where the power-load deflection point occurs be used as the power training load and not the load at which maximum P is reached. It is also proposed that loads not be described in %1-repetition maximum (RM), but as %BW. This system can be used to safely assess and train power with loaded jumps and free weights.

Effect of counter-pulsation control of a pulsatile left ventricular assist device on working load variations of the native heart.

PubMed

Choi, Seong Wook; Nam, Kyoung Won; Lim, Ki Moo; Shim, Eun Bo; Won, Yong Soon; Woo, Heung Myong; Kwak, Ho Hyun; Noh, Mi Ryoung; Kim, In Young; Park, Sung Min

2014-04-03

When using a pulsatile left ventricular assist device (LVAD), it is important to reduce the cardiac load variations of the native heart because severe cardiac load variations can induce ventricular arrhythmia. In this study, we investigated the effect of counter-pulsation control of the LVAD on the reduction of cardiac load variation. A ventricular electrocardiogram-based counter-pulsation control algorithm for a LVAD was implemented, and the effects of counter-pulsation control of the LVAD on the reduction of the working load variations of the left ventricle were determined in three animal experiments. Deviations of the working load of the left ventricle were reduced by 51.3%, 67.9%, and 71.5% in each case, and the beat-to-beat variation rates in the working load were reduced by 84.8%, 82.7%, and 88.2% in each ease after counter-pulsation control. There were 3 to 12 premature ventricle contractions (PVCs) before counter-pulsation control, but no PVCs were observed during counter-pulsation control. Counter-pulsation control of the pulsatile LVAD can reduce severe cardiac load variations, but the average working load is not markedly affected by application of counter-pulsation control because it is also influenced by temporary cardiac outflow variations. We believe that counter-pulsation control of the LVAD can improve the long-term safety of heart failure patients equipped with LVADs.

[Offshore work and the work of nurses on board: an integrative review].

PubMed

Antoniolli, Silvana Aline Cordeiro; Emmel, Suzel Vaz; Ferreira, Gímerson Erick; Paz, Potiguara de Oliveira; Kaiser, Dagmar Elaine

2015-08-01

To know the production of theoretical approaches on issues related to offshore work and the work of offshore nurses. Integrative literature review conducted in the databases of LILACS, BDENF, MEDLINE, SciELO and Index PSI. We selected 33 studies published in national and international journals between 1997 and 2014. The thematic analysis corpus resulted in four central themes: offshore work environment; amid work adversities, an escape; structuring of offshore health and safety services; in search of safe practices. This study contributes to the offshore work of nurses in relation to the nature of work, acting amid adversities and the restless search for safe practices in the open sea.

As Working Memory Grows: A Developmental Account of Neural Bases of Working Memory Capacity in 5- to 8-Year Old Children and Adults.

PubMed

Kharitonova, Maria; Winter, Warren; Sheridan, Margaret A

2015-09-01

Working memory develops slowly: Even by age 8, children are able to maintain only half the number of items that adults can remember. Neural substrates that support performance on working memory tasks also have a slow developmental trajectory and typically activate to a lesser extent in children, relative to adults. Little is known about why younger participants elicit less neural activation. This may be due to maturational differences, differences in behavioral performance, or both. Here we investigate the neural correlates of working memory capacity in children (ages 5-8) and adults using a visual working memory task with parametrically increasing loads (from one to four items) using fMRI. This task allowed us to estimate working memory capacity limit for each group. We found that both age groups increased the activation of frontoparietal networks with increasing working memory loads, until working memory capacity was reached. Because children's working memory capacity limit was half of that for adults, the plateau occurred at lower loads for children. Had a parametric increase in load not been used, this would have given an impression of less activation overall and less load-dependent activation for children relative to adults. Our findings suggest that young children and adults recruit similar frontoparietal networks at working memory loads that do not exceed capacity and highlight the need to consider behavioral performance differences when interpreting developmental differences in neural activation.

[Low risk of reproductive disorders among female greenhouse workers--safe work conditions or health selection for the light work?].

PubMed

Jurewicz, Joanna; Hanke, Wojciech; Makowiec-Dabrowska, Teresa

2008-01-01

There are two major potential hazards typical of work in greenhouses: hard physical work or exposure to pesticides. The aim of the study was to investigate whether the work in greenhouse during pregnancy have an adverse effect on its outcome (preterm delivery, spontaneous abortion and birth defects). The study was performed in a group of 460 women employed in 14 greenhouses involved in growing vegetables and flowers. The rate of spontaneous abortions was much elbeit insignificantly higher in the women working in greenhouses during pregnancy than in those employed out of them; that applied mostly to the women performing light jobs in greenhouses. An increased risk of preterm delivery and spontaneous abortion was also observed in women performing greenhouse light jobs. No significantly increased risk of birth defects was observed in children born to women working in greenhouses. Neither was there any relationship between exposure to RD or ED pesticides exposure--and the occurrence of preterm delivery, spontaneous abortion and birth defects. No higher risk of pathological pregnancy that could be associated with hard physical work and pesticide exposure was observed. This may result from the fact that women themselves select an appropriate kind of job during pregnancy and a possible removal of women with pathological pregnancy from jobs involving pesticide exposure, as well as from the promotion of biological protection. The greenhouse workers should be aware of the two typical hazards found in greenhouses (hard work and exposure to pesticides) and their potential negative effects on the reproduction. The results of this study warrant the need for further study of the effect of pesticide exposure and work load on the pregnancy outcome.

Method of preparation of removable syntactic foam

DOEpatents

Arnold, C. Jr.; Derzon, D.K.; Nelson, J.S.; Rand, P.B.

1995-07-11

Easily removable, environmentally safe, low-density, syntactic foams are disclosed which are prepared by mixing insoluble microballoons with a solution of water and/or alcohol-soluble polymer to produce a pourable slurry, optionally vacuum filtering the slurry in varying degrees to remove unwanted solvent and solute polymer, and drying to remove residual solvent. The properties of the foams can be controlled by the concentration and physical properties of the polymer, and by the size and properties of the microballoons. The suggested solute polymers are non-toxic and soluble in environmentally safe solvents such as water or low-molecular weight alcohols. The syntactic foams produced by this process are particularly useful in those applications where ease of removability is beneficial, and could find use in packaging recoverable electronic components, in drilling and mining applications, in building trades, in art works, in the entertainment industry for special effects, in manufacturing as temporary fixtures, in agriculture as temporary supports and containers and for delivery of fertilizer, in medicine as casts and splints, as temporary thermal barriers, as temporary protective covers for fragile objects, as filters for particulate matter, which matter may be easily recovered upon exposure to a solvent, as in-situ valves (for one-time use) which go from maximum to minimum impedance when solvent flows through, and for the automatic opening or closing of spring-loaded, mechanical switches upon exposure to a solvent, among other applications. 1 fig.

Method of preparation of removable syntactic foam

DOEpatents

Arnold, Jr., Charles; Derzon, Dora K.; Nelson, Jill S.; Rand, Peter B.

1995-01-01

Easily removable, environmentally safe, low-density, syntactic foams are disclosed which are prepared by mixing insoluble microballoons with a solution of water and/or alcohol-soluble polymer to produce a pourable slurry, optionally vacuum filtering the slurry in varying degrees to remove unwanted solvent and solute polymer, and drying to remove residual solvent. The properties of the foams can be controlled by the concentration and physical properties of the polymer, and by the size and properties of the microballoons. The suggested solute polymers are non-toxic and soluble in environmentally safe solvents such as water or low-molecular weight alcohols. The syntactic foams produced by this process are particularly useful in those applications where ease of removability is beneficial, and could find use in packaging recoverable electronic components, in drilling and mining applications, in building trades, in art works, in the entertainment industry for special effects, in manufacturing as temporary fixtures, in agriculture as temporary supports and containers and for delivery of fertilizer, in medicine as casts and splints, as temporary thermal barriers, as temporary protective covers for fragile objects, as filters for particulate matter, which matter may be easily recovered upon exposure to a solvent, as in-situ valves (for one-time use) which go from maximum to minimum impedance when solvent flows through, and for the automatic opening or closing of spring-loaded, mechanical switches upon exposure to a solvent, among other applications.

Membrane fusion-competent virus-like proteoliposomes and proteinaceous supported bilayers made directly from cell plasma membranes.

PubMed

Costello, Deirdre A; Hsia, Chih-Yun; Millet, Jean K; Porri, Teresa; Daniel, Susan

2013-05-28

Virus-like particles are useful materials for studying virus-host interactions in a safe manner. However, the standard production of pseudovirus based on the vesicular stomatitis virus (VSV) backbone is an intricate procedure that requires trained laboratory personnel. In this work, a new strategy for creating virus-like proteoliposomes (VLPLs) and virus-like supported bilayers (VLSBs) is presented. This strategy uses a cell blebbing technique to induce the formation of nanoscale vesicles from the plasma membrane of BHK cells expressing the hemagglutinin (HA) fusion protein of influenza X-31. These vesicles and supported bilayers contain HA and are used to carry out single particle membrane fusion events, monitored using total internal reflection fluorescence microscopy. The results of these studies show that the VLPLs and VLSBs contain HA proteins that are fully competent to carry out membrane fusion, including the formation of a fusion pore and the release of fluorophores loaded into vesicles. This new strategy for creating spherical and planar geometry virus-like membranes has many potential applications. VLPLs could be used to study fusion proteins of virulent viruses in a safe manner, or they could be used as therapeutic delivery particles to transport beneficial proteins coexpressed in the cells to a target cell. VLSBs could facilitate high throughput screening of antiviral drugs or pathogen-host cell interactions.

Topics in Safety--Topic 2: Teaching Health and Safety through Science

ERIC Educational Resources Information Center

School Science Review, 2016

2016-01-01

Science teachers always teach students the safety precautions that are necessary to carry out practical work as safely as possible. This article suggests that teachers can use these opportunities to teach students about health and safety so that they both understand why such precautions are needed and how working safely can be applied beyond the…

EPA Reaches Settlement with Two N.H. Companies for Failure to Disclose Lead Paint Information or Follow Lead-Safe Work Practices at Residential Property in Manchester

EPA Pesticide Factsheets

The U.S. EPA finalized a settlement agreement with two N.H. companies for their alleged failure to follow lead-safe work practices and provide proper lead paint disclosure to tenants at a residential property in Manchester, N.H.

[A field study on the work load and muscle fatigue at neck-shoulder in female sewing machine operators by using surface electromyography].

PubMed

Zhang, Fei-ruo; Wang, Sheng; He, Li-hua; Zhang, Ying; Wu, Shan-shan; Li, Jing-yun; Hu, Guang-yi; Ye, Kang-ping

2011-03-01

To study neck and shoulder work-related muscle fatigue of female sewing machine operators. 18 health female sewing machine operators without musculoskeletal disorders work in Beijing garment industry factory as volunteers in participate of this study. The maximal voluntary contraction (MVC) and 20% MVC of bilateral upper trapezium and cervical erectors spinae was tested before sewing operations, then the whole 20 time windows (1 time window = 10 min) sewing machine operations was monitored and the surface electromyography (sEMG) signals simultaneously was recorded after monitoring the 20%MVC was tested. Use amplitude analysis method to reduction recorded EMG signals. During work, the median load for the left cervical erector spinae (LCES), right cervical erector spinae (RCES), left upper trapezium (LUT) and right upper trapezium (RUT) respectively was 6.78 ± 1.05, 6.94 ± 1.12, 5.68 ± 2.56 and 6.47 ± 3.22, work load of right is higher than the left; static load analysis indicated the value of RMS(20%MVC) before work was higher than that value after work, the increase of right CES and UT RMS(20%MVC) was more; the largest 20%MVE of bilateral CES occurred at 20th time window, and that of bilateral UT happened at 16th. The work load of female sewing machine operators is sustained "static" load, and work load of right neck-shoulder is higher than left, right neck-shoulder muscle is more fatigable and much serious once fatigued.

Experimental determination of the effects of annealing on the micro-structures and mechanical properties of cold-worked alpha-brass

NASA Astrophysics Data System (ADS)

Edward, Aghogho Bright; Izelu, Christopher

2013-12-01

Experimental determination of the effect of annealing on the microstructure and mechanical properties of a cold work 70 - 30 brass, was carried out by subjecting specimens of the material to various degrees of cold-work (20%, 40% and 60%), by straining using a tensile machine. The specimens for each degree of cold work were then annealed at 250°C, 350°C, 450°C and 600°C, for 30 minutes. The approach involves the use of metallographic techniques: grinding, polishing and etching to reveal the microstructure while tensile test was carried out on the specimen using a Monsanto tensometer so as to obtain the load/extension graph from which the tensile strength and hardness values were obtained. From the results obtained, it was conclusive that annealing produced finer grains and eliminates prior cold work whereby the material becomes ductile. However, there should be an appreciable deformation for this effect to be noticed. One important aspect of re-crystallization in structural materials is that there is a loss of strength which accompanies disappearance of the cold-worked grains when subjected to high temperature applications. Yet, it is often difficult to establish the exact range of permissible temperature. This work establishes a range for the re-crystallization of alpha brass as 350°C < TC < 450°C, where TC is the re-crystallization temperature. Thus, it will be safe to apply this material at temperatures below 350°C, without fear of structural changes with accompanying lost in strength.

METHOD OF CONDUCTING A PERSON BETWEEN A SAFE REGION AND A DANGEROUS REGION

DOEpatents

Moulthrop, H.A.

1957-11-12

This invention relates to a method for conducting a person between a safe region and a dangerous or con taminated region so that he may work in the dangerous region without risk to himself or the hinderance of an attached tube, and without danger of contaminating the safe region. A safely suit in which a person is to work is connected by a thermoplastic tube, turned partially inside out, to a hole in the wall separating the dangerous region. The tube is sealed by pressure and separated into two parts at the seal, whereupon the person in the suit may move around freely in the dangerous area. When the person desires to exit the dangerous region, the parts of the tube are resealed, removing a portion of the tube at the seal, and the person leaves the hole whcre he entered, seals the tube to close the hole, and cuts his suit free from the tube. Bands of masking tape inside and outside of the tube at predetermined points simplify the pressure sealing of the tube at the desired points. This patent provides a simple, safe and economical method of freely working in a dangerous region.

An interval kicking progression for return to soccer following lower extremity injury.

PubMed

Arundale, Amelia; Silvers, Holly; Logerstedt, David; Rojas, Jaime; Snyder-Mackler, Lynn

2015-02-01

The majority of all soccer injuries affect the lower extremities. Regardless of whether the injured limb is an athlete's preferred kicking or stance leg, a lower extremity injury may affect their ability to impact the ball. Sport-specific biomechanical progressions to augment loading and gradually reintroduce a player to the demands of sport have been developed for upper extremity sports such as baseball, softball, tennis, and golf. Generalized return to soccer progressions have also been published in order to assist clinicians in safely returning athletes to sport; however, there are no specific progressions for the early stages of kicking designed to introduce stance leg loading and kicking leg impact. Thus, the purpose of this clinical commentary was to review the existing literature elucidating the biomechanics of kicking a soccer ball and propose a progressive kicking program to support clinicians in safely returning their soccer athletes to the demands of sport. The interval kicking program (IKP) describes clinical guidelines for readiness to begin a kicking program as well as possible readiness to return to sport measures. The program is performed on alternate days integrating therapeutic exercise and cardiovascular fitness. The IKP gradually introduces a player to the loading and impact of kicking. The progression increases kicking distance (using the markings of a soccer field as a guide), volume, and intensity and uses proposed soreness rules, effusion guidelines, and player feedback in order to assist clinicians in determining readiness for advancement though the stages. The IKP also recommends utility of specific tests and measures to determine readiness for return to sport. Gradual reintroduction to sport specific demands is essential for a safe return to soccer. This return to sport progression provides a framework integrating injury specific therapeutic exercise, cardiovascular fitness, and the return to kicking progression, to assist clinicians in initiating an athletes' return to soccer. Level 5.

Electroencephalography Based Analysis of Working Memory Load and Affective Valence in an N-back Task with Emotional Stimuli

PubMed Central

Grissmann, Sebastian; Faller, Josef; Scharinger, Christian; Spüler, Martin; Gerjets, Peter

2017-01-01

Most brain-based measures of the electroencephalogram (EEG) are used in highly controlled lab environments and only focus on narrow mental states (e.g., working memory load). However, we assume that outside the lab complex multidimensional mental states are evoked. This could potentially create interference between EEG signatures used for identification of specific mental states. In this study, we aimed to investigate more realistic conditions and therefore induced a combination of working memory load and affective valence to reveal potential interferences in EEG measures. To induce changes in working memory load and affective valence, we used a paradigm which combines an N-back task (for working memory load manipulation) with a standard method to induce affect (affective pictures taken from the International Affective Picture System (IAPS) database). Subjective ratings showed that the experimental task was successful in inducing working memory load as well as affective valence. Additionally, performance measures were analyzed and it was found that behavioral performance decreased with increasing workload as well as negative valence, showing that affective valence can have an effect on cognitive processing. These findings are supported by changes in frontal theta and parietal alpha power, parameters used for measuring of working memory load in the EEG. However, these EEG measures are influenced by the negative valence condition as well and thereby show that detection of working memory load is sensitive to affective contexts. Unexpectedly, we did not find any effects for EEG measures typically used for affective valence detection (Frontal Alpha Asymmetry (FAA)). Therefore we assume that the FAA measure might not be usable if cognitive workload is induced simultaneously. We conclude that future studies should account for potential context-specifity of EEG measures. PMID:29311875

Electroencephalography Based Analysis of Working Memory Load and Affective Valence in an N-back Task with Emotional Stimuli.

PubMed

Grissmann, Sebastian; Faller, Josef; Scharinger, Christian; Spüler, Martin; Gerjets, Peter

2017-01-01

Most brain-based measures of the electroencephalogram (EEG) are used in highly controlled lab environments and only focus on narrow mental states (e.g., working memory load). However, we assume that outside the lab complex multidimensional mental states are evoked. This could potentially create interference between EEG signatures used for identification of specific mental states. In this study, we aimed to investigate more realistic conditions and therefore induced a combination of working memory load and affective valence to reveal potential interferences in EEG measures. To induce changes in working memory load and affective valence, we used a paradigm which combines an N-back task (for working memory load manipulation) with a standard method to induce affect (affective pictures taken from the International Affective Picture System (IAPS) database). Subjective ratings showed that the experimental task was successful in inducing working memory load as well as affective valence. Additionally, performance measures were analyzed and it was found that behavioral performance decreased with increasing workload as well as negative valence, showing that affective valence can have an effect on cognitive processing. These findings are supported by changes in frontal theta and parietal alpha power, parameters used for measuring of working memory load in the EEG. However, these EEG measures are influenced by the negative valence condition as well and thereby show that detection of working memory load is sensitive to affective contexts. Unexpectedly, we did not find any effects for EEG measures typically used for affective valence detection (Frontal Alpha Asymmetry (FAA)). Therefore we assume that the FAA measure might not be usable if cognitive workload is induced simultaneously. We conclude that future studies should account for potential context-specifity of EEG measures.

Evaluation of the antitumor effect of dexamethasone palmitate and doxorubicin co-loaded liposomes modified with a sialic acid-octadecylamine conjugate.

PubMed

Sun, Jing; Song, Yanzhi; Lu, Mei; Lin, Xiangyun; Liu, Yang; Zhou, Songlei; Su, Yuqing; Deng, Yihui

2016-10-10

Dexamethasone palmitate has the potential to inhibit the activity of tumor-associated macrophages, which promote cancer proliferation, invasion, and metastasis; however, only very high and frequent doses are capable of inducing antitumor effects. With the aim to reduce the anticancer dose and decrease the nonspecific toxicity, we designed a liposomal system to co-deliver dexamethasone palmitate and doxorubicin. Furthermore, a ligand conjugate sialic acid-octadecylamine, with enhanced affinity towards the membrane receptors over-expressed in tumors, was anchored on the surface of the liposomes to increase drug distribution to the tumor tissue. Co-loaded liposomes were developed using lipid film hydration method to load dexamethasone palmitate and remote loading technology to load doxorubicin. The co-loaded liposomes modified with sialic acid-octadecylamine represented comparable physicochemical properties and blood plasma profiles with conventional co-loaded liposomes, but the biodistribution proved that sialic acid-octadecylamine modified liposomes accumulated more in tumor. The co-loaded liposomes showed higher tumor growth suppression than the single-drug loaded liposomes, while showing no additional drug toxicity in S180-bearing Kunming mice. The co-loaded liposomes modified with sialic acid-octadecylamine achieved a significantly better antitumor effect, and induced "shedding" of cancerous tissue in the mice. These finding suggested that co-loaded liposomes modified with sialic acid-octadecylamine provided a safe therapeutic strategy with outstanding anticancer activity. Copyright © 2016 Elsevier B.V. All rights reserved.

Last Mile Asset Monitoring; Low Cost Rapid Deployment Asset Monitoring

NASA Astrophysics Data System (ADS)

Zumr, Zdenek

Installation and utilization of residential distribution transformers has not changed substantially over a long period of time. Utilities typically size their transformers based on a formula that takes into account broadly what types and how many dwellings will be connected. Most new residential dwellings feature 200 Amp service per household with an anticipated energy demand of under 20,000 kWh per year. Average electrical energy consumption varies from state to state but averages to 11,280 kWh per year. Energy demand is expected to fall into a typical residential load curve that shows increased demand early in the morning, then decreasing during the day and another peak early to late evening. Distribution transformers are sized at the limit of the combined evening peak with the assumption that the transformer has enough thermal mass to absorb short overloads that may occur when concurrent loading situations among multiple dwellings arise. The assumption that concurrent loading is of short duration and the transformer can cool off during the night time has been validated over the years and has become standard practice. This has worked well when dwelling loads follow an averaging scheme and low level of coincidence. With the arrival of electric vehicles (EV's) this assumption has to be reevaluated. The acquisition of an electric vehicle in a household can drive up energy demand by over 4000 kWh per year. Potentially problematic is the increased capacity of battery packs and the resulting proliferation of Level 2 chargers. The additional load of a single Level 2 charger concurring with the combined evening peak load will push even conservatively sized distribution transformers over their nameplate rating for a substantial amount of time. Additionally, unlike common household appliances of similar power requirements such as ovens or water heaters, a Level 2 battery charger will run at peak power consumption for several hours, and the current drawn by the EVs has very high levels of harmonic distortion. The excessive loading and harmonic profile can potentially result in damaging heat build-up resulting in asset degradation. In this thesis I present a device and method that monitors pole mounted distribution transformers for overheating, collect and wirelessly upload data and initiate commands to chargers to change output levels from Level 2 to Level 1 or shut down EV charging altogether until the transformer returns into safe operational range.

The fate of chlorinated aliphatics in anaerobic treatment under transient loading

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chiu, Y.C.

1993-01-01

A CSTR with dispersed-growth anaerobic bacteria that simultaneously remove COD and chlorinated aliphatics was used. Seven chlorinated aliphatics (methylene chloride, chloroform, carbon tetrachloride, 1,1,1-trichloroethane, 1,1-dichloroethylene, trichloroethylene, and tetrachloroethylene) were biotransformed into lower-chlorinated compounds by anaerobic treatment, utilizing propionic acid (HPr) or acetic acid (HAc). The microorganisms supplied with HAc grew and were sustained at higher BSS concentrations (4,500 to 11,000 mg/L) than those with HPr (2,000 to 5,000 mg/L). The anaerobic treatment process has a considerable potential for acclimation to and biotransformation of toxic chlorinated aliphatics. For providing a safe operation range, the maximum loading rates of the chlorinated aliphaticsmore » are defined as the observed daily injection of those compounds which resulted in 50% activity of the biomass. Based on the reactor volume, the maximum chlorinated compound loading rates to the microorganisms metabolizing HPr were from 0.4 to 90 mg/L-day, while the rates ranged from 0.6 to 190 mg/L-day for the microorganisms metabolizing HAc. When based on biomass, the maximum loading rates of the microorganisms metabolizing HPr were from 0.2 to 26 mg/g cell-day, while rates for the microorganisms metabolizing HAc ranged from 0.1 to 19 mg/g cell-day. Anaerobic microorganisms have higher resistance to chlorinated aliphatic alkenes than alkanes, and can biotransform about 0.04 to 68 pound chlorinated aliphatics while simultaneously metabolizing 1,000 pounds COD. Therefore, within the safe operation range, the anaerobic process can stabilize organic pollution at a high rate while still biotransforming chlorinated aliphatics.« less

HIV transmission law in the age of treatment-as-prevention.

PubMed

Haire, Bridget; Kaldor, John

2015-12-01

Evidence that treating people with HIV early in infection prevents transmission to sexual partners has reframed HIV prevention paradigms. The resulting emphasis on HIV testing as part of prevention strategies has rekindled the debate as to whether laws that criminalise HIV transmission are counterproductive to the human rights-based public health response. It also raises normative questions about what constitutes 'safe(r) sex' if a person with HIV has undetectable viral load, which has significant implications for sexual practice and health promotion. This paper discusses a recent high-profile Australian case where HIV transmission or exposure has been prosecuted, and considers how the interpretation of law in these instances impacts on HIV prevention paradigms. In addition, we consider the implications of an evolving medical understanding of HIV transmission, and particularly the ability to determine infectiousness through viral load tests, for laws that relate to HIV exposure (as distinct from transmission) offences. We conclude that defensible laws must relate to appreciable risk. Given the evidence that the transmissibility of HIV is reduced to negligible level where viral load is suppressed, this needs to be recognised in the framing, implementation and enforcement of the law. In addition, normative concepts of 'safe(r) sex' need to be expanded to include sex that is 'protected' by means of the positive person being virally suppressed. In jurisdictions where use of a condom has previously mitigated the duty of the person with HIV to disclose to a partner, this might logically also apply to sex that is 'protected' by undetectable viral load. 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/

Young Children Can Be Key to Fire-Safe Families

ERIC Educational Resources Information Center

Kourofsky, Carolyn E.; Cole, Robert E.

2010-01-01

For more than 15 years, preschool programs nationwide have worked with Fireproof Children/Prevention First, an international center for injury prevention research and education, to bring fire safety education to young children and their families. The "play safe! be safe!"[R] curriculum includes lessons that young children can learn and understand,…

50 CFR 660.314 - Groundfish observer program.

Code of Federal Regulations, 2010 CFR

2010-10-01

... provided to the crew. (2) Safe conditions. Maintain safe conditions on the vessel for the protection of... to safe operation of the vessel, and provisions at §§ 600.725 and 600.746 of this chapter. (3... computer in working condition that contains a full Pentium 120 Mhz or greater capacity processing chip, at...

Release of Inattentional Blindness by High Working Memory Load: Elucidating the Relationship between Working Memory and Selective Attention

ERIC Educational Resources Information Center

de Fockert, Jan W.; Bremner, Andrew J.

2011-01-01

An unexpected stimulus often remains unnoticed if attention is focused elsewhere. This inattentional blindness has been shown to be increased under conditions of high memory load. Here we show that increasing working memory load can also have the opposite effect of reducing inattentional blindness (i.e., improving stimulus detection) if stimulus…

SUNRAYCE 1993: Working safely with lead-acid batteries and photovoltaic power systems

NASA Astrophysics Data System (ADS)

Dephillips, M. P.; Moskowitz, P. D.; Fthenakis, V. M.

1992-11-01

The US Department of Energy (DOE) is sponsoring SUNRAYCE 93 to advance tile technology and use of photovoltaics and electric vehicles. Participants will use cars powered by photovoltaic modules and lead-acid storage batteries. This brochure, prepared for students and faculty participating in this race, outlines the health hazards presented by these electrical systems and gives guidance on strategies for their safe usage. At the outset, it should be noted that working with photovoltaic systems and batteries requires electric vehicle drivers and technicians to have 'hands-on' contact with the car on a daily basis. It is important that no one work near a photovoltaic energy system or battery, either in a vehicle or on the bench, unless they familiarize themselves with the components in use and know and observe safe work practices including the safety precautions described in the manuals provided by the various equipment vendors and this document.

Allostatic Load and Effort-Reward Imbalance: Associations over the Working-Career

PubMed Central

Coronado, José Ignacio Cuitún; Chandola, Tarani; Steptoe, Andrew

2018-01-01

Although associations between work stressors and stress-related biomarkers have been reported in cross-sectional studies, the use of single time measurements of work stressors could be one of the reasons for inconsistent associations. This study examines whether repeated reports of work stress towards the end of the working career predicts allostatic load, a measure of chronic stress related physiological processes. Data from waves 2 to 6 of the English Longitudinal Study of Ageing (ELSA) were analysed, with a main analytical sample of 2663 older adults (aged 50+) who had at least one measurement of effort-reward imbalance between waves 2–6 and a measurement of allostatic load at wave 6. Cumulative work stress over waves 2–6 were measured by the effort-reward imbalance model. ELSA respondents who had reported two or more occasions of imbalance had a higher (0.3) estimate of the allostatic load index than those who did not report any imbalance, controlling for a range of health and socio-demographic factors, as well as allostatic load at baseline. More recent reports of imbalance were significantly associated with a higher allostatic load index, whereas reports of imbalance from earlier waves of ELSA were not. The accumulation of work related stressors could have adverse effects on chronic stress biological processes. PMID:29364177

Allostatic Load and Effort-Reward Imbalance: Associations over the Working-Career.

PubMed

Coronado, José Ignacio Cuitún; Chandola, Tarani; Steptoe, Andrew

2018-01-24

Although associations between work stressors and stress-related biomarkers have been reported in cross-sectional studies, the use of single time measurements of work stressors could be one of the reasons for inconsistent associations. This study examines whether repeated reports of work stress towards the end of the working career predicts allostatic load, a measure of chronic stress related physiological processes. Data from waves 2 to 6 of the English Longitudinal Study of Ageing (ELSA) were analysed, with a main analytical sample of 2663 older adults (aged 50+) who had at least one measurement of effort-reward imbalance between waves 2-6 and a measurement of allostatic load at wave 6. Cumulative work stress over waves 2-6 were measured by the effort-reward imbalance model. ELSA respondents who had reported two or more occasions of imbalance had a higher (0.3) estimate of the allostatic load index than those who did not report any imbalance, controlling for a range of health and socio-demographic factors, as well as allostatic load at baseline. More recent reports of imbalance were significantly associated with a higher allostatic load index, whereas reports of imbalance from earlier waves of ELSA were not. The accumulation of work related stressors could have adverse effects on chronic stress biological processes.

A high current pulsed power generator CQ-3-MMAF with co-axial cable transmitting energy for material dynamics experiments

NASA Astrophysics Data System (ADS)

Wang, Guiji; Chen, Xuemiao; Cai, Jintao; Zhang, Xuping; Chong, Tao; Luo, Binqiang; Zhao, Jianheng; Sun, Chengwei; Tan, Fuli; Liu, Cangli; Wu, Gang

2016-06-01

A high current pulsed power generator CQ-3-MMAF (Multi-Modules Assembly Facility, MMAF) was developed for material dynamics experiments under ramp wave and shock loadings at the Institute of Fluid Physics (IFP), which can deliver 3 MA peak current to a strip-line load. The rise time of the current is 470 ns (10%-90%). Different from the previous CQ-4 at IFP, the CQ-3-MMAF energy is transmitted by hundreds of co-axial high voltage cables with a low impedance of 18.6 mΩ and low loss, and then hundreds of cables are reduced and converted to tens of cables into a vacuum chamber by a cable connector, and connected with a pair of parallel metallic plates insulated by Kapton films. It is composed of 32 capacitor and switch modules in parallel. The electrical parameters in short circuit are with a capacitance of 19.2 μF, an inductance of 11.7 nH, a resistance of 4.3 mΩ, and working charging voltage of 60 kV-90 kV. It can be run safely and stable when charged from 60 kV to 90 kV. The vacuum of loading chamber can be up to 10-2 Pa, and the current waveforms can be shaped by discharging in time sequences of four groups of capacitor and switch modules. CQ-3-MMAF is an adaptive machine with lower maintenance because of its modularization design. The COMSOL Multi-physics® code is used to optimize the structure of some key components and calculate their structural inductance for designs, such as gas switches and cable connectors. Some ramp wave loading experiments were conducted to check and examine the performances of CQ-3-MMAF. Two copper flyer plates were accelerated to about 3.5 km/s in one shot when the working voltage was charged to 70 kV. The velocity histories agree very well. The dynamic experiments of some polymer bonded explosives and phase transition of tin under ramp wave loadings were also conducted. The experimental data show that CQ-3-MMAF can be used to do material dynamics experiments in high rate and low cost shots. Based on this design concept, the peak current of new generators can be increased to 5-6 MA and about 100 GPa ramp stress can be produced on the metallic samples for high pressure physics, and a conceptual design of CQ-5-MMAF was given.

A high current pulsed power generator CQ-3-MMAF with co-axial cable transmitting energy for material dynamics experiments.

PubMed

Wang, Guiji; Chen, Xuemiao; Cai, Jintao; Zhang, Xuping; Chong, Tao; Luo, Binqiang; Zhao, Jianheng; Sun, Chengwei; Tan, Fuli; Liu, Cangli; Wu, Gang

2016-06-01

A high current pulsed power generator CQ-3-MMAF (Multi-Modules Assembly Facility, MMAF) was developed for material dynamics experiments under ramp wave and shock loadings at the Institute of Fluid Physics (IFP), which can deliver 3 MA peak current to a strip-line load. The rise time of the current is 470 ns (10%-90%). Different from the previous CQ-4 at IFP, the CQ-3-MMAF energy is transmitted by hundreds of co-axial high voltage cables with a low impedance of 18.6 mΩ and low loss, and then hundreds of cables are reduced and converted to tens of cables into a vacuum chamber by a cable connector, and connected with a pair of parallel metallic plates insulated by Kapton films. It is composed of 32 capacitor and switch modules in parallel. The electrical parameters in short circuit are with a capacitance of 19.2 μF, an inductance of 11.7 nH, a resistance of 4.3 mΩ, and working charging voltage of 60 kV-90 kV. It can be run safely and stable when charged from 60 kV to 90 kV. The vacuum of loading chamber can be up to 10(-2) Pa, and the current waveforms can be shaped by discharging in time sequences of four groups of capacitor and switch modules. CQ-3-MMAF is an adaptive machine with lower maintenance because of its modularization design. The COMSOL Multi-physics® code is used to optimize the structure of some key components and calculate their structural inductance for designs, such as gas switches and cable connectors. Some ramp wave loading experiments were conducted to check and examine the performances of CQ-3-MMAF. Two copper flyer plates were accelerated to about 3.5 km/s in one shot when the working voltage was charged to 70 kV. The velocity histories agree very well. The dynamic experiments of some polymer bonded explosives and phase transition of tin under ramp wave loadings were also conducted. The experimental data show that CQ-3-MMAF can be used to do material dynamics experiments in high rate and low cost shots. Based on this design concept, the peak current of new generators can be increased to 5-6 MA and about 100 GPa ramp stress can be produced on the metallic samples for high pressure physics, and a conceptual design of CQ-5-MMAF was given.

Embracing Safe Ground Test Facility Operations and Maintenance

NASA Technical Reports Server (NTRS)

Dunn, Steven C.; Green, Donald R.

2010-01-01

Conducting integrated operations and maintenance in wind tunnel ground test facilities requires a balance of meeting due dates, efficient operation, responsiveness to the test customer, data quality, effective maintenance (relating to readiness and reliability), and personnel and facility safety. Safety is non-negotiable, so the balance must be an "and" with other requirements and needs. Pressure to deliver services faster at increasing levels of quality in under-maintained facilities is typical. A challenge for management is to balance the "need for speed" with safety and quality. It s especially important to communicate this balance across the organization - workers, with a desire to perform, can be tempted to cut corners on defined processes to increase speed. Having a lean staff can extend the time required for pre-test preparations, so providing a safe work environment for facility personnel and providing good stewardship for expensive National capabilities can be put at risk by one well-intending person using at-risk behavior. This paper documents a specific, though typical, operational environment and cites management and worker safety initiatives and tools used to provide a safe work environment. Results are presented and clearly show that the work environment is a relatively safe one, though still not good enough to keep from preventing injury. So, the journey to a zero injury work environment - both in measured reality and in the minds of each employee - continues. The intent of this paper is to provide a benchmark for others with operational environments and stimulate additional sharing and discussion on having and keeping a safe work environment.

Automation in the Space Station module power management and distribution Breadboard

NASA Technical Reports Server (NTRS)

Walls, Bryan; Lollar, Louis F.

1990-01-01

The Space Station Module Power Management and Distribution (SSM/PMAD) Breadboard, located at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama, models the power distribution within a Space Station Freedom Habitation or Laboratory module. Originally designed for 20 kHz ac power, the system is now being converted to high voltage dc power with power levels on a par with those expected for a space station module. In addition to the power distribution hardware, the system includes computer control through a hierarchy of processes. The lowest level process consists of fast, simple (from a computing standpoint) switchgear, capable of quickly safing the system. The next level consists of local load center processors called Lowest Level Processors (LLP's). These LLP's execute load scheduling, perform redundant switching, and shed loads which use more than scheduled power. The level above the LLP's contains a Communication and Algorithmic Controller (CAC) which coordinates communications with the highest level. Finally, at this highest level, three cooperating Artificial Intelligence (AI) systems manage load prioritization, load scheduling, load shedding, and fault recovery and management. The system provides an excellent venue for developing and examining advanced automation techniques. The current system and the plans for its future are examined.

Evaluation of Doxorubicin-loaded 3-Helix Micelles as Nanocarriers

PubMed Central

Dube, Nikhil; Shu, Jessica Y.; Dong, He; Seo, Jai W.; Ingham, Elizabeth; Kheirolomoom, Azadeh; Chen, Pin-Yuan; Forsayeth, John; Bankiewicz, Krystof; Ferrara, Katherine W.; Xu, Ting

2013-01-01

Designing stable drug nanocarriers, 10-30 nm in size, would have significant impact on their transport in circulation, tumor penetration and therapeutic efficacy. In the present study, biological properties of 3-helix micelles loaded with 8 wt% doxorubicin (DOX), ~15 nm in size, were characterized to validate their potential as a nanocarrier platform. DOX-loaded micelles exhibited high stability in terms of size and drug retention in concentrated protein environments similar to conditions after intravenous injections. DOX-loaded micelles were cytotoxic to PPC-1 and 4T1 cancer cells at levels comparable to free DOX. 3-helix micelles can be disassembled by proteolytic degradation of peptide shell to enable drug release and clearance to minimize long-term accumulation. Local administration to normal rat striatum by convection enhanced delivery (CED) showed greater extent of drug distribution and reduced toxicity relative to free drug. Intravenous administration of DOX-loaded 3-helix micelles demonstrated improved tumor half-life and reduced toxicity to healthy tissues in comparison to free DOX. In vivo delivery of DOX-loaded 3-helix micelles through two different routes clearly indicates the potential of 3-helix micelles as safe and effective nanocarriers for cancer therapeutics. PMID:24050265

Finite element analysis of provisional structures of implant-supported complete prostheses.

PubMed

Carneiro, Bruno Albuquerque; de Brito, Rui Barbosa; França, Fabiana Mantovani Gomes

2014-04-01

The use of provisional resin implant-supported complete dentures is a fast and safe procedure to restore mastication and esthetics of patients soon after surgery and during the adaptation phase to the new denture. This study assessed stress distribution of provisional implant-supported fixed dentures and the all-on-4 concept using self-curing acrylic resin (Tempron) and bis-acrylic resin (Luxatemp) to simulate functional loads through the three-dimensional finite element method. Solidworks software was used to build three-dimensional models using acrylic resin (Tempron, model A) and bis-acrylic resin (Luxatemp, model B) for denture captions. Two loading patterns were applied on each model: (1) right unilateral axial loading of 150 N on the occlusal surfaces of posterior teeth and (2) oblique loading vector of 150 N at 45°. The results showed that higher stress was found on the bone crest below oblique load application with a maximum value of 187.57 MPa on model A and 167.45 MPa on model B. It was concluded that model B improved stress distribution on the denture compared with model A.

Non-linear programming in shakedown analysis with plasticity and friction

NASA Astrophysics Data System (ADS)

Spagnoli, A.; Terzano, M.; Barber, J. R.; Klarbring, A.

2017-07-01

Complete frictional contacts, when subjected to cyclic loading, may sometimes develop a favourable situation where slip ceases after a few cycles, an occurrence commonly known as frictional shakedown. Its resemblance to shakedown in plasticity has prompted scholars to apply direct methods, derived from the classical theorems of limit analysis, in order to assess a safe limit to the external loads applied on the system. In circumstances where zones of plastic deformation develop in the material (e.g., because of the large stress concentrations near the sharp edges of a complete contact), it is reasonable to expect an effect of mutual interaction of frictional slip and plastic strains on the load limit below which the global behaviour is non dissipative, i.e., both slip and plastic strains go to zero after some dissipative load cycles. In this paper, shakedown of general two-dimensional discrete systems, involving both friction and plasticity, is discussed and the shakedown limit load is calculated using a non-linear programming algorithm based on the static theorem of limit analysis. An illustrative example related to an elastic-plastic solid containing a frictional crack is provided.

Working memory regulates trait anxiety-related threat processing biases.

PubMed

Booth, Robert W; Mackintosh, Bundy; Sharma, Dinkar

2017-06-01

High trait anxious individuals tend to show biased processing of threat. Correlational evidence suggests that executive control could be used to regulate such threat-processing. On this basis, we hypothesized that trait anxiety-related cognitive biases regarding threat should be exaggerated when executive control is experimentally impaired by loading working memory. In Study 1, 68 undergraduates read ambiguous vignettes under high and low working memory load; later, their interpretations of these vignettes were assessed via a recognition test. Trait anxiety predicted biased interpretation of social threat vignettes under high working memory load, but not under low working memory load. In Study 2, 53 undergraduates completed a dot probe task with fear-conditioned Japanese characters serving as threat stimuli. Trait anxiety predicted attentional bias to the threat stimuli but, again, this only occurred under high working memory load. Interestingly however, actual eye movements toward the threat stimuli were only associated with state anxiety, and this was not moderated by working memory load, suggesting that executive control regulates biased threat-processing downstream of initial input processes such as orienting. These results suggest that cognitive loads can exacerbate trait anxiety-related cognitive biases, and therefore represent a useful tool for assessing cognitive biases in future research. More importantly, since biased threat-processing has been implicated in the etiology and maintenance of anxiety, poor executive control may be a risk factor for anxiety disorders. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Measuring Load on Working Memory: The Use of Heart Rate as a Means of Measuring Chemistry Students' Cognitive Load

ERIC Educational Resources Information Center

Cranford, Kristen N.; Tiettmeyer, Jessica M.; Chuprinko, Bryan C.; Jordan, Sophia; Grove, Nathaniel P.

2014-01-01

Information processing provides a powerful model for understanding how learning occurs and highlights the important role that cognitive load plays in this process. In instances in which the cognitive load of a problem exceeds the available working memory, learning can be seriously hindered. Previously reported methods for measuring cognitive load…