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1

Manned Certification Evaluation of the Innerspace Systems (registered trademark) Megalodon Underwater Breathing Apparatus.  

National Technical Information Service (NTIS)

The Megalodon underwater breathing apparatus (UBA) was used in completing 99 man-dives. The primary test objective was to determine whether the UBA could control oxygen sufficiently to satisfy performance specifications published by Naval Surface Warfare ...

B. M. Keuski D. J. Doolette

2010-01-01

2

Testing Procedures for Closed-Circuit and Semi-Closed Circuit Underwater Breathing Apparatus.  

National Technical Information Service (NTIS)

The purpose of the study is to outline the general procedures and equipment to be used by EDU personnel in the evaluation of semi-closed circuit underwater breathing apparatus. It is intended as a detailed guide with which the project engineer can plan th...

S. D. Reimers

1974-01-01

3

A Method of Measuring Oxygen Consumption and Minute Ventilation in Semi-Closed Circuit Underwater Breathing Apparatus  

Microsoft Academic Search

A method of measuring both oxygen uptake ([Vdot]O2) and ventilation ( [Vdot]) when breathing from a double counterlung semi-closed circuit underwater breathing apparatus is presented. The analysis requires a knowledge of the gas concentrations of oxygen and carbon dioxide in the inspired and expired counterlungs of the breathing set as well as the mass flow rate of gas injected into

PHILIP A. HAYES; JOHN T. FLORIO; JOHN GOODER

1979-01-01

4

Low-back problems in recreational self-contained underwater breathing apparatus divers: Prevalence and specific risk factors  

Microsoft Academic Search

Low-back problems (LBP) are one of the most common musculoskeletal disorders in the general population, with reported lifetime prevalences of 50% to 80%. Also, certain sports participants (e.g. gymnasts, alpine skiers, runners) are at risk of LBP and its repercussions. This epidemiological study was undertaken to examine the lifetime and 1-year prevalence of LBP among recreational Flemish self-contained breathing apparatus

K. Knaepen; E. Cumps; E. Zinzen; R. Meeusen

2009-01-01

5

Performance Comparison of Rescue Breathing Apparatus.  

National Technical Information Service (NTIS)

A performance comparison of 14 rescue breathing apparatus was undertaken as an assessment of past and present worldwide technology. Rescue breathing apparatus are self-contained, close-circuit breathing apparatus used for entry into areas having atmospher...

N. Kyriazi

1999-01-01

6

Turbulence-Induced Acoustic Emission of SCUBA Breathing Apparatus  

NASA Astrophysics Data System (ADS)

Our initial study, [1], demonstrated that the primary originating source of vibration and subsequent acoustic emission from an underwater breathing apparatus is turbulent air flow pressure fluctuations occurring during the inhale phase of breathing. The process of energy release associated with the expansion of compressed air in the high pressure scuba tank, through the first stage regulator, results in a highly turbulent, unsteady, compressible air flow. The paper presents results of experimental investigation and fluid dynamic simulation of turbulence-induced acoustic emission. The simulation reveals complex supersonic flow within the regulator's valve and channel topology. The associated regulator's air turbulent pressure pulsations and underwater acoustic emission are observed in a broadband frequency range.

Donskoy, D.; Imas, L.; Yen, T.; Sedunov, N.; Tsionskiy, M.; Sedunov, A.

2008-06-01

7

Lightweight Rescue Breathing Apparatus Final Report.  

National Technical Information Service (NTIS)

A lightweight compressed oxygen rescue breathing apparatus (RBA) for rescue and recovery missions in mine rescue work was developed for the Bureau of Mines. The RBA is a positive pressure, closed circuit system that lasts 4 hours. The weight of the comple...

E. E. Buban W. C. Koenemund

1981-01-01

8

30 CFR 57.22315 - Self-contained breathing apparatus (V-A mines).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Self-contained breathing apparatus (V-A mines). 57.22315...Equipment § 57.22315 Self-contained breathing apparatus (V-A mines). Self-contained breathing apparatus of a duration to...

2013-07-01

9

42 CFR 84.71 - Self-contained breathing apparatus; required components.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Self-contained breathing apparatus; required components. 84...RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.71 Self-contained breathing apparatus; required components....

2010-10-01

10

42 CFR 84.70 - Self-contained breathing apparatus; description.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 false Self-contained breathing apparatus; description. 84.70 Section...RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.70 Self-contained breathing apparatus; description. (a)...

2009-10-01

11

42 CFR 84.70 - Self-contained breathing apparatus; description.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Self-contained breathing apparatus; description. 84.70 Section...RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.70 Self-contained breathing apparatus; description. (a)...

2010-10-01

12

42 CFR 84.71 - Self-contained breathing apparatus; required components.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 false Self-contained breathing apparatus; required components. 84...RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.71 Self-contained breathing apparatus; required components....

2009-10-01

13

Remotely operated submersible underwater suction apparatus  

DOEpatents

A completely submersible, remotely operated underwater suction device for collection of irradiated materials in a nuclear pool is disclosed. The device includes a pump means for pumping water through the device, a filter means for capturing irradiated debris, remotely operated releasable connector means, a collection means and a means for remotely maneuvering the collection means. The components of the suction device may be changed and replaced underwater to take advantage of the excellent radiation shielding ability of water to thereby minimize exposure of personnel to radiation.

Kristan, Louis L. (2111 Brentwood Dr., Idaho Falls, ID 83402)

1990-01-01

14

Apparatus and method for monitoring breath acetone and diabetic diagnostics  

SciTech Connect

An apparatus and method for monitoring diabetes through breath acetone detection and quantitation employs a microplasma source in combination with a spectrometer. The microplasma source provides sufficient energy to produce excited acetone fragments from the breath gas that emit light. The emitted light is sent to the spectrometer, which generates an emission spectrum that is used to detect and quantify acetone in the breath gas.

Duan, Yixiang (Los Alamos, NM); Cao, Wenqing (Los Alamos, NM)

2008-08-26

15

46 CFR 167.45-60 - Emergency breathing apparatus and flame safety lamps.  

Code of Federal Regulations, 2011 CFR

...false Emergency breathing apparatus and flame safety lamps. 167.45-60 Section...45-60 Emergency breathing apparatus and flame safety lamps. Each nautical-school...Charge, Marine Inspection. (b) One flame safety lamp approved by the Coast...

2011-10-01

16

46 CFR 167.45-60 - Emergency breathing apparatus and flame safety lamps.  

Code of Federal Regulations, 2012 CFR

...false Emergency breathing apparatus and flame safety lamps. 167.45-60 Section...45-60 Emergency breathing apparatus and flame safety lamps. Each nautical-school...Charge, Marine Inspection. (b) One flame safety lamp approved by the Coast...

2012-10-01

17

46 CFR 196.37-20 - Self-contained breathing apparatus and gas masks.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Self-contained breathing apparatus and gas masks. 196.37-20 Section 196.37-20 Shipping...196.37-20 Self-contained breathing apparatus and gas masks. (a) Lockers or spaces containing...

2012-10-01

18

46 CFR 196.37-20 - Self-contained breathing apparatus and gas masks.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Self-contained breathing apparatus and gas masks. 196.37-20 Section 196.37-20 Shipping...196.37-20 Self-contained breathing apparatus and gas masks. (a) Lockers or spaces containing...

2011-10-01

19

46 CFR 108.703 - Self-contained breathing apparatus.  

Code of Federal Regulations, 2012 CFR

...breathing apparatus described in § 108.497(a) to use as protection against gas leaking from a refrigeration unit if it is equipped with any refrigeration unit using (1) Ammonia to refrigerate any space with a volume of more than 20...

2012-10-01

20

Gas Mask Filters Test Apparatus Using a Breathing Pump.  

National Technical Information Service (NTIS)

The present invention relates in general to equipment and methods for testing filters, and in particular to a new and useful apparatus and method for testing a gas mask filter under simulated breathing conditions and using test animals. According to the i...

J. T. James L. C. Buettner J. A. Genovese

1985-01-01

21

A Comparison of the Physiological Responses to Underwater Arm Cranking and Breath Holding Between Synchronized Swimmers and Breath Holding Untrained Women  

PubMed Central

Exercise and breath holding in the water such as that performed in the sport of synchronized swimming may evoke the physiological consequences of the diving response. The purpose of this study was to investigate the physiological responses of breath holding during underwater arm cranking in synchronized swimmers who are trained in breath holding and compare these responses to untrained women. Each participant performed 6 breath holding periods in the water (2 10s, 2 20s and 2 25s) with 2 minutes of normal breathing in between, in either an ascending or descending order while performing arm crank exercise. The intensity of arm crank exercise was set below the individual ventilatory threshold. Both synchronized swimmers and controls were matched on sitting height and then randomly divided into 2 groups: one group started breath holding with the longest (25s) breath holding periods while the other group began breath holding with the shortest (10s) breath holding periods. The synchronized swimmers experienced a significant decrease in heart rate while breath holding for 20 and 25s but the changes in heart rate for the control group was not consistent between subgroups. Full recovery from breath holding was identified for minute ventilation after 25s of recovery from breath holding for all groups. Results suggest synchronized swimmers exhibited a better adaptation to breath holding while exercising underwater.

Alentejano, Teresa C.; Bell, Gordon J.; Marshall, Dru

2012-01-01

22

Ultrasound lung comets induced by repeated breath-hold diving, a study in underwater fishermen.  

PubMed

Pulmonary edema has been reported in breath-hold divers during fish-catching diving activity. The present study was designed to detect possible increases in extravascular lung water (EVLW) in underwater fishermen after a competition. Thirty healthy subjects were studied. They participated in two different 5-h fish-catching diving competitions: one organized in the winter (10 subjects) and one organized in the autumn (20 subjects). A questionnaire was used to record underwater activity and note respiratory problems. An increase in EVLW was investigated from the detection of ultrasound lung comets (ULC) by chest ultrasonography. Complementary investigations included echocardiography and pulmonary function testing. An increase in EVLW was detected in three out of 30 underwater fishermen after the competition. No signs of cardiovascular dysfunction were found in the entire population and in divers with an increase in the ULC score. Two divers with raised ULC presented respiratory disorders such as cough or shortness of breath. Impairment in spirometric parameters was recorded in these subjects. An increase in EVLW could be observed after a fish-catching diving competition in three out of 30 underwater fishermen. In two subjects, it was related to respiratory disorders and impairment in pulmonary flow. PMID:21535186

Boussuges, A; Coulange, M; Bessereau, J; Gargne, O; Ayme, K; Gavarry, O; Fontanari, P; Joulia, F

2011-04-28

23

Microcontroller-based underwater acoustic ECG telemetry system  

Microsoft Academic Search

This paper presents a microcontroller-based underwater acoustic telemetry system for digital transmission of the electrocar- diogram (ECG). The system is designed for the real time, through- water transmission of data representing any parameter, and it was used initially for transmitting in multiplexed format the heart rate, breathing rate and depth of a diver using self-contained underwater breathing apparatus (SCUBA). Here,

Robert S. H. Istepanian; Bryan Woodward

1997-01-01

24

46 CFR 195.30-15 - Self-contained breathing apparatus.  

Code of Federal Regulations, 2012 CFR

...CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Protection From Refrigerants § 195.30-15 Self-contained breathing apparatus. (a) Each vessel must have a self-contained breathing...

2012-10-01

25

46 CFR 195.30-15 - Self-contained breathing apparatus.  

Code of Federal Regulations, 2011 CFR

...CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Protection From Refrigerants § 195.30-15 Self-contained breathing apparatus. (a) Each vessel must have a self-contained breathing...

2011-10-01

26

46 CFR 96.30-15 - Self-contained breathing apparatus.  

Code of Federal Regulations, 2012 CFR

...CONTINUED) CARGO AND MISCELLANEOUS VESSELS VESSEL CONTROL AND MISCELLANEOUS SYSTEMS AND EQUIPMENT Protection From Refrigerants § 96.30-15 Self-contained breathing apparatus. (a) Each vessel must have a self-contained breathing...

2012-10-01

27

42 CFR 84.71 - Self-contained breathing apparatus; required components.  

Code of Federal Regulations, 2012 CFR

...SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus...Breathing bag; (9) Safety relief valve or safety relief system; and (10) Harness. (b) The components of each...

2012-10-01

28

42 CFR 84.71 - Self-contained breathing apparatus; required components.  

Code of Federal Regulations, 2011 CFR

...SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus...Breathing bag; (9) Safety relief valve or safety relief system; and (10) Harness. (b) The components of each...

2011-10-01

29

Method and apparatus for deep underwater well drilling and completion  

SciTech Connect

A method and apparatus are disclosed for remotely establishing an underwater well under conditions of great water depth including a drilling guide structure located on the floor of the body of water; a single handling and guiding string extending upwardly from the drilling guide structure and maintained in tension by an elongated buoy; a series of drilling guide arm units, flowline guide arm units and wellhead guide arm units to be lowered down the string, oriented relative to desired well positions and then retrieved once the wells have been drilled and the wellheads and flowlines secured in place; and a production gathering assembly to be lowered down the string, oriented relative to the wellheads and flowlines, and then coupled to these wellheads and flowlines. The orientation is accomplished between an orientation member on the outer surface of a tubular member extending upwardly from the guide structure and orientation members on the inner surfaces of open-ended members in the drilling guide arm units, flowline guide arm units, wellhead guide arm units and the production gathering assembly.

Lawson, J.E.

1984-01-24

30

Canadian Underwater Mine Apparatus: Unmanned Performance Validation of the Second Prototype Second Stage Regulator.  

National Technical Information Service (NTIS)

The Canadian Underwater Mine Apparatus (CUMA) is a rebreather type apparatus employing a self-contained gas supply system that mixes pure oxygen with a diluent gas. The resultant gas mixture supplied to the counterlung has a constant oxygen partial pressu...

D. Eaton

1989-01-01

31

Method and Apparatus for Diagnosing Sleep Breathing Disorders while a Patient is Awake.  

National Technical Information Service (NTIS)

This invention is generally related to methods and apparatus for performing medical diagnoses and particularly to a method and apparatus for enabling the diagnosis of sleep breathing disorders or other physiological respiratory dysfunction while the patie...

R. A. Katz M. S. Lawee A. K. Newman

2000-01-01

32

Work of breathing is increased during exercise with the self-contained breathing apparatus regulator.  

PubMed

The self-contained breathing apparatus (SCBA) increases the expiratory pressure required to maintain high rates of ventilation, suggesting that the expiratory work of breathing (WOB) is increased; however, this has never been reported. The objective of this study, therefore, was to determine if the WOB is increased with the SCBA regulator (BA condition) compared with a low-resistance breathing valve (RV condition) during exercise. Twelve healthy male subjects underwent two randomized exercise trials, consisting of cycling at 150, 180, 210, and 240 W. Inspired and expired tidal volumes were measured using a body plethysmograph, whereas esophageal pressures were measured with an esophageal balloon. Modified Campbell diagrams were created to calculate the resistive and elastic components of WOB during inspiration and expiration. There were no differences in WOB between BA and RV conditions at 150 W. End-inspiratory and -expiratory lung volumes were elevated (p < 0.05) in the BA condition at higher ventilation rates, which increased inspiratory elastic work and decreased expiratory elastic work at 180 and 210 W (p < 0.05). At 240 W (VE=112 +/- 17 L.min-1 in the BA condition), active expiratory resistive work increased by 59% +/- 51%, inspiratory elastic work increased by 26% +/- 24%, and total WOB increased by 13% +/- 12% in the BA condition (p < 0.05). The SCBA regulator causes an increase in the active expiratory resistive work to maintain high ventilatory rates and an increase inspiratory elastic work through an elevation in lung volumes. PMID:17213883

Butcher, Scott J; Jones, Richard L; Eves, Neil D; Petersen, Stewart R

2006-12-01

33

46 CFR 28.205 - Fireman's outfits and self-contained breathing apparatus.  

Code of Federal Regulations, 2011 CFR

...equipped with at least two fireman's outfits stowed in widely separated locations. (b) Each vessel that uses ammonia as a refrigerant must be equipped with at least two self-contained breathing apparatuses. (c) A fireman's outfit must consist...

2011-10-01

34

46 CFR 28.205 - Fireman's outfits and self-contained breathing apparatus.  

Code of Federal Regulations, 2012 CFR

...equipped with at least two fireman's outfits stowed in widely separated locations. (b) Each vessel that uses ammonia as a refrigerant must be equipped with at least two self-contained breathing apparatuses. (c) A fireman's outfit must consist...

2012-10-01

35

Method and apparatus for remote control of an underwater valve  

SciTech Connect

This patent describes an apparatus for remotely controlling operation of a subsea valve in a fluid transmission pipeline with an acoustic signal transmitted from the surface to the subsea valve, the valve including a valve stem rotatable for controlling the flow of fluid through the valve body and thus the transmission line. The apparatus consists of a control housing fixedly connected to the valve body; a valve actuator housing fixedly connected to the control housing; an actuator shaft rotatably mounted within the valve actuator housing; means for applying a preselected torque to the actuator shaft; a control means rotatably mounted within the control housing; and disconnecting means adjacent the subsea valve for automatically deactivating the mechanical connector means in response to the acoustic signal, such that deactivation of the mechanical connector means automatically operates the valve in response to the preselected torque of the biasing means.

Carman, R.J.; Fitzgibbons, M.R.; Sweety, J.A.

1989-02-21

36

Assessment of Organism Efficiency While Working in Breathing Apparatus.  

National Technical Information Service (NTIS)

The following types of respiratory protective equipment were evaluated: (1) A mask type MA-1 fitted with a hydrogen cyanide absorber; (2) an apparatus type LA; and (3) a protective apparatus for sand blasting workers. Investigations carried out in industr...

T. Comte

1973-01-01

37

Divers swimming efficiency as a function of buoyancy, swimming attitude, protective garments, breathing apparatus, swimming technique and fin type'.  

National Technical Information Service (NTIS)

The overall purpose of this series of studies was to determine the energy cost of underwater swimming and the effects of: (1) buoyancy and body position (2) fin selection (3) Swimming time (4) body cooling (5) protective garments (6) breathing gear on the...

D. R. Pendergast

1993-01-01

38

Quantitatively Measuring In situ Flows using a Self-Contained Underwater Velocimetry Apparatus (SCUVA)  

PubMed Central

The ability to directly measure velocity fields in a fluid environment is necessary to provide empirical data for studies in fields as diverse as oceanography, ecology, biology, and fluid mechanics. Field measurements introduce practical challenges such as environmental conditions, animal availability, and the need for field-compatible measurement techniques. To avoid these challenges, scientists typically use controlled laboratory environments to study animal-fluid interactions. However, it is reasonable to question whether one can extrapolate natural behavior (i.e., that which occurs in the field) from laboratory measurements. Therefore, in situ quantitative flow measurements are needed to accurately describe animal swimming in their natural environment. We designed a self-contained, portable device that operates independent of any connection to the surface, and can provide quantitative measurements of the flow field surrounding an animal. This apparatus, a self-contained underwater velocimetry apparatus (SCUVA), can be operated by a single scuba diver in depths up to 40 m. Due to the added complexity inherent of field conditions, additional considerations and preparation are required when compared to laboratory measurements. These considerations include, but are not limited to, operator motion, predicting position of swimming targets, available natural suspended particulate, and orientation of SCUVA relative to the flow of interest. The following protocol is intended to address these common field challenges and to maximize measurement success.

Katija, Kakani; Colin, Sean P.; Costello, John H.; Dabiri, John O.

2011-01-01

39

Study of facepiece leakage of self-contained breathing apparatus by DOP man tests. Progress report, July 1, 1971February 29, 1972  

Microsoft Academic Search

Protection factors (PF's) for Self-Contained Breathing Apparatus (SCBA) have been proposed. The revised B of M Approval Schedules do not have provisions for the determination of protection factors for Self-Contained Breathing Apparatus (SCBA). A protection factor is a measure of the degree of protection afforded by a respiratory protective device during use and is defined as the ratio of the

E. C. Hyatt; C. P. Richards

1972-01-01

40

An atypical case of taravana syndrome in a breath-hold underwater fishing champion: a case report.  

PubMed

Dysbaric accidents are usually referred to compressed air-supplied diving. Nonetheless, some cases of decompression illness are known to have occurred among breath-hold (BH) divers also, and they are reported in the medical literature. A male BH diver (57 years old), underwater fishing champion, presented neurological disorders as dizziness, sensory numbness, blurred vision, and left frontoparietal pain after many dives to a 30-35 meters sea water depth with short surface intervals. Symptoms spontaneously regressed and the patient came back home. The following morning, pain and neurological impairment occurred again and the diver went by himself to the hospital where he had a generalized tonic-clonic seizure and lost consciousness. A magnetic resonance imaging of the brain disclofsed a cortical T1-weighted hypointense area in the temporal region corresponding to infarction with partial hemorrhage. An early hyperbaric oxygen therapy led to prompt resolution of neurological findings. All clinical and imaging characteristics were referable to the Taravana diving syndrome, induced by repetitive prolonged deep BH dives. The reappearance of neurological signs after an uncommon 21-hour symptom-free interval may suggest an atypical case of Taravana syndrome. PMID:23970902

Cortegiani, Andrea; Foresta, Grazia; Strano, Giustino; Strano, Maria Teresa; Montalto, Francesca; Garbo, Domenico; Raineri, Santi Maurizio

2013-07-22

41

Use of Superoxide Mixtures as Air-Revitalization Chemicals in Hyperbaric, Self-Contained, Closed-Circuit Breathing Apparatus.  

National Technical Information Service (NTIS)

In portable breathing apparatus applications at 1 atm, potassium superoxide (KO2) has exhibited low-utilization efficiency of the available oxygen (O2) and diminished carbon dioxide-(CO2) scrubbing capacity caused by the formation of a fused, hydrated-hyd...

P. C. Wood T. Wydeven

1985-01-01

42

Effects of firefighters' self-contained breathing apparatus' weight and its harness design on the physiological and subjective responses  

Microsoft Academic Search

To examine the effects of firefighters' self-contained breathing apparatus' (SCBA) weight and its harness design on the physiological and subjective responses, eight male students performed treadmill exercise under four conditions: the 8kg firefighter protective clothing (PC) (Control), the PC + an 11kg SCBA with an old harness (Test A), the PC + a 6.4kg SCBA with an old harness (Test

Ilham Bakri; Joo-Young Lee; Kouhei Nakao; Hitoshi Wakabayashi; Yutaka Tochihara

2012-01-01

43

Estimated workplace protection factors for positive-pressure self-contained breathing apparatus.  

PubMed

An analytical model is presented that estimates the distribution of workplace protection factor (WPF) values for positive-pressure respirators. Input for the model is (1) the instantaneous facepiece pressure measured as a function of time and (2) the distribution of WPF values for a negative-pressure version of the respirator. As an example application, the model was applied to 57 measurements of facepiece pressure made in a previous National Institute for Occupational Safety and Health study called "Firesmoke." That study involved professional firefighters wearing positive-pressure self-contained breathing apparatus (SCBA). During Firesmoke, there were four donnings in which facepiece pressure momentarily went negative one or more times during use. The purpose of the effort described here was to assess the significance of these momentary, negative excursions in facepiece pressure. To that end, an analytical model was developed that estimates the ratio of the mass of contaminant that enters the facepiece during these negative excursions to that which would be expected to enter a negative-pressure respirator utilizing the same facepiece. Thus, the performance of a positive-pressure SCBA can be determined relative to the performance of a negative-pressure respirator with the same facepiece--either a negative-pressure SCBA or a negative pressure air-purifying respirator. The NIOSH-assigned protection factor (APF) for a negative-pressure full facepiece is 50; the APF for a positive-pressure SCBA is 10,000. The results of the application of this analytical model are consistent with the current NIOSH APF for a positive-pressure SCBA. PMID:8209837

Campbell, D L; Noonan, G P; Merinar, T R; Stobbe, J A

1994-04-01

44

Underwater connection apparatus  

SciTech Connect

This patent describes, in a subsea system for the production of oil or gas from subsurface formations or the injection of liquids or gases into subsurface formations, a subsea system for landing and securing ocean floor flowlines to the system, comprising a flowline receiving structure having two slide plates which are space apart, a first circular hole in each side plate on a first centerline, and a circular projection on each side plate about the first centerline; a flowline end connection suitable for attaching directly to the flowlines before the flowlines are lowered into the water. It includes a first spring loaded pin on each side of the flowline end connection on a second centerline with the second centerline being at right angles to the centerline of the flowlines, a funnel shaped means with a cylindrical stop surface at the bottom of the funnel shaped area on each side of the flowline end connection with the cylindrical stop surface about the second centerline, and circular fixed pin members on each side of the flowline end connection for attachment of pulling tool means also about the second centerline; and a pulling tool means with a guidance nose means including attachment means for engaging the circular fixed pin members and a connection to a wire rope or the such like, a receptacle means for receiving and positioning the guidance nose means, and a wire rope means which can be tensioned to pull the guidance nose means toward and into the receptacle means.

Baugh, B.F.

1987-02-10

45

Do fire-fighters develop specific ventilatory responses in order to cope with exercise whilst wearing self-contained breathing apparatus?  

Microsoft Academic Search

In the present study we compared the ventilatory performance whilst wearing self-contained breathing apparatus (SCBA) during\\u000a exercise, of a group of male fire-fighters (FF, n?=?8), with a matched group of male civilians (CV, n?=?7). The mean (SEM) physiological characteristics of the subjects (FF vs CV) were: age 31 (2)?years vs 32 (4)?years; height\\u000a 179 (2)?cm vs 183 (3)?cm, P??1?vs 4.39

K. J. Donovan; A. K. McConnell

1999-01-01

46

Energetics of underwater swimming with SCUBA.  

PubMed

Underwater swimming has unique features of breathing apparatus (SCUBA), thermal protective gear, and fins. The energy cost of underwater swimming is determined by the drag while swimming and the net mechanical efficiency. These are influenced by the cross-sectional area of the diver and gear and the frequency of the leg kick. The speeds that divers can achieve are relatively low, thus the VO(2) increases linearly with values of VO(2)*d(-1) of 30-50 l*km(-1)for women and men, respectively. Diving experience had little effect on VO(2) for women; however, male divers with experience had lower VO(2) than beginners. The location and density of the gear can alter the diver's attitude in the water and increase the energy cost of swimming by 30 percent at slow speeds. The type of fin used has an effect on the depth and frequency of the kick, thus on drag and efficiency, with a range of VO(2) from 25 to 50 l*km(-1). A large flexible fin had the lowest energy cost and a large rigid fin the highest. Adding extra air tanks or a dry suit increased the cost of swimming by 25 percent. The energy cost of underwater swimming is influenced by gender, gear and its placement, fin type, and experience of the diver. PMID:9148086

Pendergast, D R; Tedesco, M; Nawrocki, D M; Fisher, N M

1996-05-01

47

Underwater manipulator  

DOEpatents

Self-contained, waterproof, water-submersible, remote-controlled apparatus is described for manipulating a device, such as an ultrasonic transducer for measuring crack propagation on an underwater specimen undergoing shock testing. The subject manipulator includes metal bellows for transmittal of angular motions without the use of rotating shaft seals or O-rings. Inside the manipulator, a first stepper motor controls angular movement. In the preferred embodiment, the bellows permit the first stepper motor to move an ultrasonic transducer [plus minus]45 degrees in a first plane and a second bellows permit a second stepper motor to move the transducer [plus minus]10 degrees in a second plane orthogonal to the first. In addition, an XY motor-driven table provides XY motion.

Schrum, P.B.; Cohen, G.H.

1993-04-20

48

Underwater manipulator  

DOEpatents

Self-contained, waterproof, water-submersible, remote-controlled apparatus is provided for manipulating a device, such as an ultrasonic transducer for measuring crack propagation on an underwater specimen undergoing shock testing. The subject manipulator includes metal bellows for transmittal of angular motions without the use of rotating shaft seals or O-rings. Inside the manipulator, a first stepper motor controls angular movement. In the preferred embodiment, the bellows permit the first stepper motor to move an ultrasonic transducer .+-.45 degrees in a first plane and a second bellows permit a second stepper motor to move the transducer .+-.10 degrees in a second plane orthogonal to the first. In addition, an XY motor-driven table provides XY motion.

Schrum, Phillip B. (Clairton, PA); Cohen, George H. (Pittsburgh, PA)

1993-01-01

49

Respirator studies for the Nuclear Regulatory Commission. Evaluation and performance of escape-type self-contained breathing apparatus. Progress report, October 1, 1978-September 30, 1979  

SciTech Connect

The performance of escape type breathing apparatus was evaluated for weight, comfort, ease of use, and protection factor (calculated from facepiece leakage). All of the devices tested provided a self-contained air supply of 5- to 15-min duration. Five of them have the provision to connect an air line but allow the use of the self-contained supply for safe egress. The air supply was stored in cylinders, tubing, or disposable containers. Respiratory inlet coverings were half masks, full facepieces, hoods, and mouthpieces. An estimate is given for the ease of quick donning. Recommendations for conditions of use of the equipment are given. 8 refs., 10 figs., 3 tabs.

Hack, A.; Trujillo, A.; Carter, K.; Bradley, O.D.

1980-07-01

50

Emergency Response Breathing Apparatus.  

National Technical Information Service (NTIS)

Aerospace Design & Development, Inc.'s (ADD's) SCAMP was developed under an SBIR contract through Kennedy Space Center. SCAMP stands for Supercritical Air Mobility Pack. The technology came from the life support fuel cell support systems used for the Apol...

2000-01-01

51

42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.  

Code of Federal Regulations, 2012 CFR

...SAFETY AND HEALTH RESEARCH AND RELATED ACTIVITIES APPROVAL OF RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus...Compressed breathing gas contained valves or a separate charging system or adapter provided with each apparatus shall be equipped...

2012-10-01

52

42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Compressed breathing gas and liquefied breathing gas containers; minimum requirements. 84...RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.81 Compressed...

2010-10-01

53

42 CFR 84.81 - Compressed breathing gas and liquefied breathing gas containers; minimum requirements.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Compressed breathing gas and liquefied breathing gas containers; minimum requirements. 84...RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.81 Compressed...

2009-10-01

54

Breathing systems  

Microsoft Academic Search

The classification of apparatus used to deliver inhalational anaesthetic agents to a patient has undergone numerous revisions over the years. The classical terms, open, semi-open, semi-closed and closed, were applicable to the use of ether and are now outdated. Small changes in geometry and gas flow rates can lead to conversion from one type to another, causing confusion.The term breathing

Timothy Lovell

2004-01-01

55

Breathing Like a Fish  

ERIC Educational Resources Information Center

|Being able to dive and breathe underwater has been a challenge for thousands of years. In 1980, Fuji Systems of Tokyo developed a series of prototype gills for divers as a way of demonstrating just how good its membranes are. Even though gill technology has not yet reached the point where recipients can efficiently use implants to dive

Katsioloudis, Petros J.

2010-01-01

56

42 CFR 84.91 - Breathing resistance test; exhalation.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 2009-10-01 false Breathing resistance test; exhalation. 84.91 Section 84...Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation airflow will be...

2009-10-01

57

42 CFR 84.79 - Breathing gas; minimum requirements.  

Code of Federal Regulations, 2010 CFR

... 2009-10-01 2009-10-01 false Breathing gas; minimum requirements. 84.79 Section...RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.79 Breathing gas; minimum requirements. (a)...

2009-10-01

58

42 CFR 84.85 - Breathing bags; minimum requirements.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 2010-10-01 false Breathing bags; minimum requirements. 84.85 Section...RESPIRATORY PROTECTIVE DEVICES Self-Contained Breathing Apparatus § 84.85 Breathing bags; minimum requirements. (a)...

2010-10-01

59

Breath sounds  

MedlinePLUS

... care provider if you have wheezing or other abnormal breathing sounds. See also: Breathing difficulty Your health care ... did it last? How would you describe your breathing? What makes it ... discovers abnormal breath sounds. You may not even notice them. ...

60

Underwater Acoustics.  

ERIC Educational Resources Information Center

Summarizes the history of underwater acoustics and describes related research studies and teaching activities at the University of Birmingham (England). Also includes research studies on transducer design and mathematical techniques. (SK)

Creasey, D. J.

1981-01-01

61

42 CFR 84.91 - Breathing resistance test; exhalation.  

Code of Federal Regulations, 2011 CFR

...Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation airflow will...open-circuit apparatus with air flowing at a continuous rate...minute. (b) The exhalation resistance of demand apparatus...

2011-10-01

62

Underwater Rays  

ERIC Educational Resources Information Center

|Light beams in wavy unclear water, also called underwater rays, and caustic networks of light formed at the bottom of shallow water are two faces of a single phenomenon. Derivation of the caustic using only simple geometry, Snell's law and simple derivatives accounts for observations such as the existence of the caustic network on vertical walls,

Cepic, Mojca

2008-01-01

63

Underwater Concreting.  

National Technical Information Service (NTIS)

The placing of underwater concrete by tremie, by skip and the special process of grouted aggregate were reviewed. It was noted that problems with broken seals and coverage of large areas by the tremie affect its usefulness when compared with the skip. Als...

1971-01-01

64

Underwater breathing: the mechanics of plastron respiration  

Microsoft Academic Search

The rough, hairy surfaces of many insects and spiders serve to render them water- repellent; consequently, when submerged, many are able to survive by virtue of a thin air layer trapped along their exteriors. The diusion of dissolved oxygen from the am- bient water may allow this layer to function as a respiratory bubble or 'plastron', and so enable certain

M. R. FLYNN; JOHN W. M. BUSH

2008-01-01

65

Underwater communication goes cognitive  

Microsoft Academic Search

Underwater acoustic channel is the most challenging channel in the world due to its time varying and frequency-selective characters. These facts obstruct the realization of most of intelligent and high bit rate underwater communication systems. Cognitive underwater communication systems build up rules of modulation method and receiver algorithm over time through learning from continuous experiential interactions with the underwater environment.

Wang Yonggang; Tang Jiansheng; Pan Yue; Huangfu Li

2008-01-01

66

Bad Breath  

MedlinePLUS

... breath? Maybe you shouldn't have put extra onions on your hamburger at lunch. What's a kid ... bad breath: foods and drinks, such as garlic, onions, cheese, orange juice, and soda poor dental hygiene ( ...

67

Lamaze Breathing  

PubMed Central

Lamaze breathing historically is considered the hallmark of Lamaze preparation for childbirth. This column discusses breathing in the larger context of contemporary Lamaze. Controlled breathing enhances relaxation and decreases perception of pain. It is one of many comfort strategies taught in Lamaze classes. In restricted birthing environments, breathing may be the only nonpharmacological comfort strategy available to women. Conscious breathing and relaxation, especially in combination with a wide variety of comfort strategies, can help women avoid unnecessary medical intervention and have a safe, healthy birth.

Lothian, Judith A.

2011-01-01

68

42 CFR 84.88 - Breathing bag test.  

Code of Federal Regulations, 2011 CFR

...continuous period of twice the rated time of the apparatus (except for...test period shall be the rated time of the apparatus). (b...during this test by a breathing machine with 24 respirations per minute...liters. (c) A breathing machine cam with a work rate of...

2011-10-01

69

Underwater Radiance Scanner.  

National Technical Information Service (NTIS)

The Underwater Radiance Scanner was developed to measure radiance distributions of natural light fields underwater. It was deployed in a series of experiments designed to validate a model describing propagation of optical energy from a satellite to an und...

R. D. Anderson

1976-01-01

70

Decompression Sickness Following Seawater Hunting Using Underwater Scooters  

Microsoft Academic Search

Since the 1960s there have been several reports of divers suffering from decompression sickness (DCS) after repetitive breath-hold (BH) diving. In the period from 1995 to 2000 John Batle observed apparent DCS in 30 free divers competing with underwater scooters in the sea around Mallorca. The cases were treated successfully with recompression therapy. Two of the typical diving profiles, described

Hans-Christian M. Thorsen; Gustavo Zubieta-Calleja; Poul-Erik Paulev

2007-01-01

71

Blow-off float vehicle recovery apparatus  

US Patent & Trademark Office Database

The invention in one variation is a modular recovery apparatus for dispensing a tether spool having a tow line with a float, where the tow line can be used to retrieve an unmanned underwater vehicle and other underwater platforms. The modular recovery apparatus can be triggered underwater or on the surface, and being modular in configuration it is suitable to be fitted to a variety of unmanned underwater vehicles (UUVs). The apparatus has a tether spool that is spring loaded, such that when the tether spool is deployed, the spring expels the tether spool with sufficient force to clearly separate it from the UUV. One end of the tow line is typically fastened to a tow point on the UUV, and an opposing end is attached to the float. When the tether spool is deployed, the tow line unwinds from the float, providing a securable length.

Gibson; Robert (Panama City, FL); Hollis; Walt (Panama City, FL); Leasko; Robert A. (Panama City, FL)

2012-05-01

72

Breathing Blue  

NSDL National Science Digital Library

In this demonstration of chemical change, the presenter blows breath into a methylene blue solution releasing carbon dioxide which acidifies the water and changes it from a bright blue color to green.

Wosu

2009-08-20

73

Apparatus for Control of Stator Wakes.  

National Technical Information Service (NTIS)

This patent application discloses an apparatus that controls the wake of stator blades on an underwater vehicle. The apparatus comprises one or more stator blades, each with a movable trailing edge that when actuated in a controlled manner produces a peri...

D. N. Beal

2009-01-01

74

Breathing and Holding Your Breath  

NSDL National Science Digital Library

Students begin with interactive activities to develop a basic understanding of why cells need oxygen and need to get rid of carbon dioxide, how the circulatory and respiratory systems cooperate to bring oxygen and remove carbon dioxide from cells all over the body, and how the nervous system regulates breathing. Then, students carry out an experiment to test whether changing levels of oxygen and carbon dioxide influence how long they can hold their breath.

Waldron, Ingrid; Doherty, Jennifer

75

Breathing difficulty - lying down  

MedlinePLUS

... breath; Paroxysmal nocturnal dyspnea; PND; Difficulty breathing while lying down; Orthopnea ... Obesity (does not directly cause difficulty breathing while lying down but often aggravates other conditions that lead ...

76

Multiple position underwater birthing stool  

US Patent & Trademark Office Database

A birthing stool is disclosed comprising a series of closed walls constructed from a non porous rigid material, molded into compound curves. The stool facilitates a range of physiologically effective positioning for labor and delivery and can be used submerged underwater during waterbirth. The stool ergonomically supports the body while also achieving structural integrity through a simple organic form that can be produced inexpensively using minimal material. All elements of the stool, including a seat portion that accommodates a laboring woman and her birthing partner, as well as handles and grips for carrying are integrated into a single part design, facilitating effective cleansing and disinfection of the apparatus. The invention includes the method of production of the stool, and describes method of using device.

2013-04-02

77

Breathing Yeasties  

NSDL National Science Digital Library

Does yeast breathe? Find out by watching how plastic bags filled with yeast, warm water and different amounts of sugar change over time. Demonstrate the interaction of microorganisms and the carbon cycle with yeast, sugar and water, and discover how organisms are dependent on water and energy flow.

Columbia River Exhibition of History, Science and Technology (CREHST)

1999-01-01

78

Breathing Difficulties  

MedlinePLUS

... stiffness may depress the breathing centers in the brain. It is important to let your physician know the names of all the medications you are taking (both prescription and over-the-counter drugs). Also, let him/her know that you are ...

79

Underwater Adhesives/Attachments.  

National Technical Information Service (NTIS)

The long-term goal of the research is to expand mission capabilities of Naval Special Warfare (NSW) in the underwater attachment of munitions and sensor packages on a variety of surfaces, quickly, covertly, and under extreme environmental conditions. The ...

B. Courson B. J. Love C. Holton J. Crivello J. W. Grant

1998-01-01

80

Advancements in Underwater Inspection.  

National Technical Information Service (NTIS)

This report summarizes the advancement of underwater inspection and nondestructive evaluation capabilities being made in the Structural Integrity Monitoring Program, a joint industry program in the United Kingdom. Inspection techniques are discussed that ...

K. R. Bitting

1989-01-01

81

Underwater Imaging Studies.  

National Technical Information Service (NTIS)

This project was concerned with advancing the understanding of both the theoretical underpinnings of underwater image formation theory and also the experimental development of a new system for obtaining three dimensional information about ocean optical pr...

J. S. Jaffe

1996-01-01

82

Underwater Blowout Control.  

National Technical Information Service (NTIS)

A method for evaluating underwater blowout control measures has been developed. Among the measures evaluated in this report are preventive measures, early stopping methods, subsea oil collection, well injection of dispersants and surface collection. One o...

R. H. Westergaard

1983-01-01

83

Underwater Acoustic Tracer System.  

National Technical Information Service (NTIS)

This patent application discloses an underwater supercavitating projectile that includes means to form ripples on its surrounding cavity so as to provide well-defined disturbances of the cavity boundary. As the ripples move aft of the supercavitating proj...

R. Kuklinski

2009-01-01

84

Adaptive Underwater Acoustic Communications  

Microsoft Academic Search

\\u000a Underwater wireless networks consist of mobile and static nodes, which usually communicate using the acoustic channel since\\u000a radio transmissions attenuate rapidly and optical communication is only suitable for short distances. The underwater acoustic\\u000a channel is plagued with issues of high transmission power requirements, rapidly changing channel characteristics, multi-path\\u000a echoes, possible high ambient noise, high and varying propagation delays. To achieve

Anuj Sehgal; Jrgen Schnwlder

2010-01-01

85

Deep breathing after surgery  

MedlinePLUS

... take an active role is by doing deep breathing exercises. Deep breathing keeps your lungs healthy while you ... or as your doctor prescribes. Do these deep-breathing exercises as directed by your doctor or nurse.

86

Breath-Holding Spells  

MedlinePLUS

... only a few seconds before a child regains consciousness and resumes breathing normally. In most cases, breath- ... spells cause kids to stop breathing and lose consciousness for up to a minute. In the most ...

87

Breath holding spell  

MedlinePLUS

... then no breathing Fainting or loss of alertness (consciousness) Jerky movements (short, seizure-like movements) Normal breathing ... 8. Cildren who have a seizure after losing consciousness during a breath holding spell do not appear ...

88

Special High Grade Underwater Concrete,  

National Technical Information Service (NTIS)

The authors have engaged in developing special high grade underwater concrete. Special high grade underwater concrete should have the following properties: No segregation when dropped into water; No pollution (no alkali or cement comes out into surroundin...

M. Sakamoto T. Hatsuzaki

1987-01-01

89

Click production during breathing in a sperm whale (Physeter macrocephalus)  

NASA Astrophysics Data System (ADS)

A sperm whale (Physeter macrocephalus) was observed at the surface with above- and underwater video and synchronized underwater sound recordings. During seven instances the whale ventilated its lungs while clicking. From this observation it is inferred that click production is achieved by pressurizing air in the right nasal passage, pneumatically disconnected from the lungs and the left nasal passage, and that air flows anterior through the phonic lips into the distal air sac. The capability of breathing and clicking at the same time is unique among studied odontocetes and relates to the extreme asymmetry of the sperm whale sound-producing forehead.

Wahlberg, Magnus; Frantzis, Alexandros; Alexiadou, Paraskevi; Madsen, Peter T.; Mhl, Bertel

2005-12-01

90

Breathing Earth  

NSDL National Science Digital Library

Visual simulation and representation programs and applications have been popping up online in greater numbers, and this recent find is one that will pique the interest of scientists, policy makers, and others who are concerned about carbon dioxide emission rates across the Earth. The Breathing Earth site was created by David Bleja, and he draws on a number of resources (such as the World Factbook and the United Nations) for the data that is utilized to create this site. Visitors can scroll over different countries to learn about their population, their emissions, and their birth and death rate. This interactive map and educational resource also contains a legend in the right-hand corner which explains the various symbols in use here.

Bleja, David

91

Fast Clear Single Underwater Image  

Microsoft Academic Search

In underwater situations, clarify of images are degraded by light absorption and scattering. In order to restore the original clarity of the images underwater, we analyze the physical effects of visibility degradation, and present an algorithm which inverts the image formation process. In this paper, we consider the visibility restoration from a single underwater image as a particular filtering problem

Yan Wang; Bo Wu

2010-01-01

92

Security in Underwater Sensor Network  

Microsoft Academic Search

Underwater wireless sensor network is a novel type of underwater networked system. Due to the characteristics of UWSN and underwater channel, UWSN are vulnerable to malicious attacks. The existing security solutions proposed for WSN cannot be used directly in UWSN. Moreover, most of these solutions are layer wise. In this paper, we studied the threat, attack, and security issues of

Yanping Cong; Guang Yang; Zhiqiang Wei; Wei Zhou

2010-01-01

93

UNDERWATER SOUND RECORDING OF ANIMALS  

Microsoft Academic Search

Underwater sound recording of animals uses specialized techniques to obtain faithful copies of sounds produced by animals during their normal activities underwater. Techniques have to be unobtrusive as well as nondisturbing to avoid changing the animal behaviors. The first scientific recording of underwater sounds from a marine mammal at sea was by William E. Schevill and Barbara Lawrence in 1948.

WILLIAM A. WATKINS; MARY ANN DAHER

1992-01-01

94

Underwater optical wireless communication network  

Microsoft Academic Search

The growing need for underwater observation and subsea monitoring systems has stimulated considerable interest in advancing the enabling technologies of underwater wireless communication and underwater sensor networks. This communication technology is expected to play an important role in investigating climate change, in monitoring biological, biogeochemical, evolutionary, and ecological changes in the sea, ocean, and lake environments, and in helping to

Shlomi Arnon

2010-01-01

95

Underwater Optical Load Cell System.  

National Technical Information Service (NTIS)

A system is provided for detecting movement of an object underwater. A housing positioned underwater defines a gas-filled cavity receiving an optical reflector that is fixedly coupled to an object underwater. At least one optical sensor is adjustably posi...

W. H. Nedderman

1999-01-01

96

Offshore multiple well drilling and production apparatus  

SciTech Connect

A modular multiple well drilling and production template structure is combined with a production riser base module to provide an underwater apparatus which allows a plurality of wells to be drilled, completed and produced by operations carried out from a single vessel or platform without remote installation of flowlines.

Kirkland, K.G.; Masciopinto, A.J.

1980-03-11

97

Breathing difficulties - first aid  

MedlinePLUS

Breathing difficulties can range from being short of breath, unable to take a deep breath, gasping for air, or feeling like you are not getting enough air. This article discusses first aid for someone who is having breathing problems. See also: Choking

98

Underwater glider motion control  

Microsoft Academic Search

This paper describes an underwater glider motion control system intended to enhance locomotive efficiency by reducing the energy expended by vehicle guidance. In previous work, the authors derived an approximate analytical expression for steady turning motion by applying regular perturbation theory to a realistic vehicle model. The analysis results suggested the use of a well-known time-optimal path planning procedure developed

Nina Mahmoudian; Craig Woolsey

2008-01-01

99

Underwater acoustic glider  

Microsoft Academic Search

Underwater gliders are buoyancy-driven devices; they alternately reduce and expand displaced volume to dive and climb through the ocean. Gliders carry wings and control their pitch attitude to effectuate a horizontal speed component through the ocean. They turn by rolling their wings or by use of a rudder. Buoyancy control, coupled with hydrodynamic lift is a natural choice for a

Eric O. Rogers; Genderson JG; Weston S. Smith; Gerald F. Denny; Paul J. Farley

2004-01-01

100

Impact of breath holding on cardiovascular respiratory and cerebrovascular health.  

PubMed

Human underwater breath-hold diving is a fascinating example of applied environmental physiology. In combination with swimming, it is one of the most popular forms of summer outdoor physical activities. It is performed by a variety of individuals ranging from elite breath-hold divers, underwater hockey and rugby players, synchronized and sprint swimmers, spear fishermen, sponge harvesters and up to recreational swimmers. Very few data currently exist concerning the influence of regular breath holding on possible health risks such as cerebrovascular, cardiovascular and respiratory diseases. A literature search of the PubMed electronic search engine using keywords 'breath-hold diving' and 'apnoea diving' was performed. This review focuses on recent advances in knowledge regarding possibly harmful physiological changes and/or potential health risks associated with breath-hold diving. Available evidence indicates that deep breath-hold dives can be very dangerous and can cause serious acute health problems such a collapse of the lungs, barotrauma at descent and ascent, pulmonary oedema and alveolar haemorrhage, cardiac arrest, blackouts, nitrogen narcosis, decompression sickness and death. Moreover, even shallow apnoea dives, which are far more frequent, can present a significant health risk. The state of affairs is disturbing as athletes, as well as recreational individuals, practice voluntary apnoea on a regular basis. Long-term health risks of frequent maximal breath holds are at present unknown, but should be addressed in future research. Clearly, further studies are needed to better understand the mechanisms related to the possible development or worsening of different clinical disorders in recreational or competitive breath holding and to determine the potential changes in training/competition regimens in order to prevent these adverse events. PMID:22574634

Dujic, Zeljko; Breskovic, Toni

2012-06-01

101

Rapid shallow breathing  

MedlinePLUS

Tachypnea; Breathing - rapid and shallow; Fast shallow breathing; Respiratory rate - rapid and shallow ... your oxygen level is too low and nebulized respiratory treatments if you are having an asthma attack.

102

Natural Underwater Adhesives  

PubMed Central

The general topic of this review is protein-based underwater adhesives produced by aquatic organisms. The focus is on mechanisms of interfacial adhesion to native surfaces and controlled underwater solidification of natural water-borne adhesives. Four genera that exemplify the broad range of function, general mechanistic features, and unique adaptations are discussed in detail: blue mussels, acorn barnacles, sandcastle worms, and freshwater caddisfly larva. Aquatic surfaces in nature are charged and in equilibrium with their environment, populated by an electrical double layer of ions as well as adsorbed natural polyelectrolytes and microbial biofilms. Surface adsorption of underwater bioadhesives likely occurs by exchange of surface bound ligands by amino acid sidechains, driven primarily by relative affinities and effective concentrations of polymeric functional groups. Most aquatic organisms exploit modified amino acid sidechains, in particular phosphorylated serines and hydroxylated tyrosines (dopa), with high-surface affinity that form coordinative surface complexes. After delivery to the surfaces as a fluid, permanent natural adhesives solidify to bear sustained loads. Mussel plaques are assembled in a manner superficially reminiscent of in vitro layer-by-layer strategies, with sequentially delivered layers associated through Fe(dopa)3 coordination bonds. The adhesives of sandcastle worms, caddisfly larva, and barnacles may be delivered in a form somewhat similar to in vitro complex coacervation. Marine adhesives are secreted, or excreted, into seawater that has a significantly higher pH and ionic strength than the internal environment. Empirical evidence suggests these environment triggers could provide minimalistic, fail-safe timing mechanisms to prevent premature solidification (insolubilization) of the glue within the secretory system, yet allow rapid solidification after secretion. Underwater bioadhesives are further strengthened by secondary covalent curing.

Stewart, Russell J.; Ransom, Todd C.; Hlady, Vladimir

2011-01-01

103

Underwater Stud Welding  

Microsoft Academic Search

Stud welding is a simple process which requires no skill of the operator. Experiments were conducted to determine whether underwater stud welding could be made. Most experiments were made with mild-steel studs 3\\/4 inch in diameter. Base plates used were mild steel and HY-80 steel, 1\\/2 and 1 inch (6.4 and 25.4 mm) thick. It was found that stud welding

K. Masubuchi; H. Ozaki; J. Chiba

1978-01-01

104

Underwater laser system  

NASA Astrophysics Data System (ADS)

We have developed a solid-state laser operating at 532nm for underwater topographic investigations. The laser system is integrated into a torpedo-like 'towed-body', with the military designation of AQS-20. This laser, along with other sophisticated receiver opto-electronic systems enables detailed underwater bathymetry. CEO designed and manufactured the laser portion of this system. The laser sub-system is comprised of two separate parts: the LTU (Laser Transmitter Unit) and the LEU (Laser Electronics Unit). The LTU and LEU where put through Mil-standard testing for vibration, shock and temperature storage and operation extremes as well as Mil-461C EMI/EMC testing. The Nd:YAG laser operates at a 400 Hz pulse repetition frequency and is controlled remotely, tethered to the system controller in a ship or helicopter. Power monitor circuits allow real time laser health monitoring, which enables input parameter adjustments for consistent laser behavior. The towed body moves forward at a constant rate of speed while this underwater LIDAR system gathers data. All heat generated must be conducted into the outer hull of the towed-body and then, to the surrounding ambient ocean water. The water temperature may vary from 0-35 degrees C.

Kushina, Mark E.; Heberle, Geoff; Hope, Michael; Crittenden, Ryan M.; Bethel, Mike

2002-03-01

105

Do Pressure-Demand Breathing Systems Safeguard Against Inward Leakage?  

Microsoft Academic Search

Rescue operations conducted in toxic atmospheres require respiratory protective equipment capable of providing a very high degree of protection. A slight positive pressure in the facepiece throughout the breathing cycle is used in the pressure-demand, compressed-air breathing apparatus to eliminate any inward leakage. In the present work an inward leakage test with sulphur hexafluoride (SF6) was used to measure facepiece

GUNNAR O. DAHLBCK; LUBOS NOVAK

1983-01-01

106

Submarines, spacecraft and exhaled breath.  

PubMed

Foreword The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled breath. What may have escaped our notice is a complementary field of research that explores the creation and maintenance of artificial atmospheres practised by the submarine air monitoring and air purification (SAMAP) community. SAMAP is comprised of manufacturers, researchers and medical professionals dealing with the engineering and instrumentation to support human life in submarines and spacecraft (including shuttlecraft and manned rockets, high-altitude aircraft, and the International Space Station (ISS)). Here, the immediate concerns are short-term survival and long-term health in fairly confined environments where one cannot simply 'open the window' for fresh air. As such, one of the main concerns is air monitoring and the main sources of contamination are CO(2) and other constituents of human exhaled breath. Since the inaugural meeting in 1994 in Adelaide, Australia, SAMAP meetings have been held every two or three years alternating between the North American and European continents. The meetings are organized by Dr Wally Mazurek (a member of IABR) of the Defense Systems Technology Organization (DSTO) of Australia, and individual meetings are co-hosted by the navies of the countries in which they are held. An overriding focus at SAMAP is life support (oxygen availability and carbon dioxide removal). Certainly, other air constituents are also important; for example, the closed environment of a submarine or the ISS can build up contaminants from consumer products, cooking, refrigeration, accidental fires, propulsion and atmosphere maintenance. However, the most immediate concern is sustaining human metabolism: removing exhaled CO(2) and replacing metabolized O(2). Another important concern is a suite of products from chemical reactions among oxidizing compounds with biological chemicals such as amines, thiols and carbonyls. SAMAP Meeting We (Armin and Joachim) attended the 2011 SAMAP conference in Taranto, Italy (10-14 October), which occurred just a few weeks after the IABR meeting in Parma, Italy (11-15 September 2011). It was held at the Officers' Club of the Taranto Naval Base under the patronage of the Italian navy; the local host was Lucio Ricciardi of the University of Insubria, Varese, Italy. At the 2011 SAMAP meeting, the theme was air-independent propulsion (AIP), meaning the capability of recharging the main batteries of the submarine without the need to surface. Only a few navies (e.g. US, UK, France, Russia, China) have historically had this capability using nuclear-powered submarines that can function underwater for extended periods of time (months). Most navies operate submarines with conventional diesel-electric propulsion, wherein diesel-powered generators charge battery banks which then drive an electric motor connected to the propeller. The batteries are charged while the boat is on the surface or during snorkelling, when the boat is submerged a few meters below the surface and a snorkel tube is extended to the surface. The period between battery charges can vary from several hours to one or two days depending on the power requirements and the nature of the mission. The process is necessary for breathing air revitalization (flushing out accumulated contaminants) and for the operation of the diesel engines. However, during this period the submarine is vulnerable to detection. Since the 1940s there have been various attempts to develop a power generation system that is independent of external air (AIP). To this end hydrogen peroxide was initially used and later liquid oxygen (LOX). Currently, most AIP submarines use fuel cell technology (LOX and hydrogen) to supplement the conventional diesel-electric system in order to extend the underwater endurance to 2-3 weeks. These propulsion engineering changes also reduce per

Pleil, Joachim D; Hansel, Armin

2012-02-27

107

Deep underwater measurements with ionization calorimeter  

NASA Astrophysics Data System (ADS)

The technical and physical properties in the registration of interactions induced by muons and neutrinos of different origin in deep underwater conditions are discussed. These problems make necessary the development of an installation in which the deflectors have an isolated working volume, and are therefore independent of the ambient properties (seawater transparency, the presence of fluorescent microorganisms and scattered daylight). The installation includes 100 calorimetric modules, each of which is 10 x 10 sq m in size and 1500 g/sq cm in density, and consists of five planes of ionization chambers of scintillation deflectors. The proposed apparatus can detect about 50 muons of the neutrino beam from one operating accelerator at a distance of 7000 km in one year, as well as register about 2,000 atmospheric neutrinos with energies above 0.5 GeV.

Bashindzhagian, G. L.; Demianov, A. I.; Murzin, V. S.; Sarycheva, L. I.; Sinev, N. B.

108

Underwater wet welding of steel  

Microsoft Academic Search

Underwater wet welding is conducted directly in water with the shielded metal arc (SMA) and flux cored arc (FCA) welding processes. Underwater wet welding has been demonstrated as an acceptable repair technique down to 100 meters (325 ft.) in depth, but wet welds have been attempted on carbon steel structures down to 200 meters (650 ft.). The primary purpose of

S. Ibarra; S. Liu; D. L. Olson

1995-01-01

109

Submersibles: Submersed in Underwater Technology  

NSDL National Science Digital Library

This data tip from Bridge, the Ocean Sciences Education Teacher Resource Center archive, focuses on underwater exploration technology such as submersibles, scuba diving, and underwater research habitat. It includes links to a variety of educational sites, and a data activity that uses coral mortality data collected by students as part of the JASON XI expedition project at Conch Reef near Key Largo, Florida.

2000-04-01

110

International regulation of underwater sound  

Microsoft Academic Search

Underwater sound is created by myriad activities worldwide and there is general agreement that manmade noise in the ocean is increasing. This rise in anthropogenic sound in the ocean has generated concern that it is affecting marine mammal behavior and could affect humans as well. Controversy over underwater sound and its effects on marine mammals has generated much discussion within

Elena M. McCarthy

2000-01-01

111

Fiber laser hydrophone for underwater acoustic surveillance and marine mammals monitoring  

Microsoft Academic Search

This work describes the progress in the developing of a hydrophonic sensors array, based on fiber laser technology, tailored for underwater acoustic surveillance of harbors, naval forces, and, in general, of maritime areas of strategic relevance; the same apparatus can also find application for marine mammals coastline surveying, simply addressing a suitable frequency detection band. The sensors are Distributed Bragg

N. Beverini; S. Firpi; P. Guerrini; E. Maccioni; A. Maguer; M. Morganti; F. Stefani; C. Trono

2010-01-01

112

Apparatus Notes.  

ERIC Educational Resources Information Center

|Describes three pieces of scientific apparatus and their demonstrational use: a high temperature apparatus for positron annihilation studies, a digitally synthesized classroom variable star, and a demonstration of plasma laser-beam focusing using paint stripper flames. (GA)|

Eaton, Bruce G., Ed.

1978-01-01

113

Underwater gas tornado  

NASA Astrophysics Data System (ADS)

We present the first experimental observation of a new hydrodynamic phenomenon, the underwater tornado. Simple measurements show that the tornado forms a vortex of the Rankine type, i.e. the rising gas rotates as a solid body and the liquid rotates with a velocity decreasing hyperbolically with the radius. We obtain the dependence of the tornado radius a on the gas stream value j theoretically: a ? j2/5. Processing of a set of experiments yielded the value 0.36 for the exponent in this expression. We also report the initial stages of the theoretical study of this phenomenon.

Byalko, Alexey V.

2013-07-01

114

Breath-by-breath alveolar gas exchange.  

PubMed

A method is described for breath-by-breath measurement of alveolar gas exchange corrected for changes of lung gas stores. In practice, the subject inspires from a spirometer, and each expired tidal volume is collected into a rubber bag placed inside a rigid box connected to the same spirometer. During the inspiration following any given expiration the bag is emptied by a vacuum pump. A computer monitors inspiratory and expiratory tidal volumes, drives four solenoid valves allowing appropriate operation of the system, and memorizes end-tidal gas fractions as well as mixed expired gas composition analyzed by mass spectrometer. Thus all variables for calculating alveolar gas exchange, based on the theory developed by Auchincloss et al. (J. Appl. Physiol. 21: 810-818, 1966), are obtained on a single-breath basis. Mean resting and steady-state exercise gas exchange data are equal to those obtained by conventional open-circuit measurements. Breathing rates up to 30 X min-1 can be followed. The breath-to-breath variability of O2 uptake at the alveolar level is less (25-35%) than that measured at the mouth as the difference between the inspired and expired volumes, both at rest and during exercise up to 0.7 of maximum O2 consumption. PMID:6618950

Giezendanner, D; Cerretelli, P; Di Prampero, P E

1983-08-01

115

Electrotherapy apparatus  

US Patent & Trademark Office Database

An apparatus for producing analgesia in a patient through electrical signals applied through electrodes to a patient's body, and methods of treating patients using the apparatus. The apparatus comprises a signal generator arranged to generate a biphasic waveform comprising successive cycles each containing a positive and negative pulse.

Littlewood; Roger Kenneth (Axbridge Somerset, GB); Macdonald; Alexander John Ranald (Bristol Avon, GB); Coates; Timothy William (Winscombe Somerset, GB); Gillbe; Ivor Stephen (Bristol Avon, GB)

2013-04-23

116

CARBON MONOXIDE AND WATER VAPOR CONTAMINATION OF COMPRESSED BREATHING AIR FOR FIREFIGHTERS AND DIVERS  

Microsoft Academic Search

Compressed breathing air, used in self-contained breathing apparatus (SCBA) by firefighters and other categories of workers as well as by recreational and commercial divers, is prepared with the aid of high-pressure compressors operating in the range of 5000 psig. There have been reports of unexplained deaths of SCUBA divers and anecdotal accounts of decreased time to exhaustion in firefighters using

C. C. Austin; D. J. Ecobichon; G. Dussault; C. Tirado

1997-01-01

117

Underwater green laser vibrometry  

NASA Astrophysics Data System (ADS)

We have developed a laser vibrometer based on an monolithic single-frequency green laser operating at 532 nm. This wavelength can be particularly useful in the case of underwater vibrometry, especially with regard to the minimum of water absorption for this wavelength range (blue-green window). Using polarizing optics, we proposed a configuration that allows the elimination of parasitic reflections at the air-glass-water boundary. A measurement of heterodyne signals as a mixing result of scattered and reference beams has been performed. The study was conducted in aqueous medium for the scattering waterproof paper and retro-reflective surface. In both configurations we have obtained signals with a relatively high S/N ratio > 20 dB (for scattering surface) and > 31 dB (for retro-reflective tape) with the Resolution Bandwidth RBW 10 kHz for a vibrometer output power of 5 mW and the distance to the moving object 1.2 m (including 0.3 m in air). In our opinion, laser Doppler vibrometry LDV based on high-performance single frequency solid-state lasers with a wavelength range corresponding to the blue-green window allows effective measurement of vibration in the underwater environment.

Anto?czak, Arkadiusz J.; Kozio?, Pawe?; Wa?, Adam T.; Sotor, Jaros?aw Z.; Dudzik, Grzegorz; Kaczmarek, Pawe? R.; Abramski, Krzysztof M.

2012-06-01

118

Coated Timber for Underwater Applications.  

National Technical Information Service (NTIS)

The protection of timber (West African mahogany, Khaya ivorensis) when used in the underwater environment was investigated. Trials were undertaken in the sea off Clump Point, North Queensland, to determine the resistance of timber coated with reinforced a...

P. Dunn G. F. Sansom

1972-01-01

119

Underwater wet welding of steel  

SciTech Connect

Underwater wet welding is conducted directly in water with the shielded metal arc (SMA) and flux cored arc (FCA) welding processes. Underwater wet welding has been demonstrated as an acceptable repair technique down to 100 meters (325 ft.) in depth, but wet welds have been attempted on carbon steel structures down to 200 meters (650 ft.). The primary purpose of this interpretive report is to document and evaluate current understanding of metallurgical behavior of underwater wet welds so that new welding consumables can be designed and new welding practices can be developed for fabrication and repair of high strength steel structures at greater depths. First the pyrometallurgical and physical metallurgy behaviors of underwater weldments are discussed. Second, modifications of the welding consumables and processes are suggested to enhance the ability to apply wet welding techniques.

Ibarra, S. [Amoco Corporation Research, Naperville, IL (United States); Liu, S.; Olson, D.L. [Colorado School of Mines, Golden, CO (United States)

1995-05-01

120

Underwater Robotics: Science, Design & Fabrication  

NSDL National Science Digital Library

This website includes information on the textbook Underwater Robotics: Science, Design & Fabrication by Steven W. Moore, Harry Bohm and Vickie Jensen. The site includes information about the content of the book as well as sample material.

2011-09-20

121

Underwater Television and Fish Behavior.  

National Technical Information Service (NTIS)

Reprints of two published studies on the behavior and sonic activity of the bicolor damselfish, Eupomacentrus partitus, as determined in the field (Bimini Video-Acoustic Installation) and laboratory. Also, a review of underwater television, as used in stu...

A. A. Myrberg

1974-01-01

122

Remote Sensing of Underwater Sound.  

National Technical Information Service (NTIS)

The work performed on a research program investigating interaction mechanisms for sensing underwater sound from a platform above the sea is reviewed. Two mechanisms were studied: the modulation of the electric permittivity of the salt water by the acousti...

W. K. Rivers

1970-01-01

123

Underwater Radiation Detector.  

National Technical Information Service (NTIS)

A detector apparatus for differentiating between gamma and neutron radiation is provided. The detector includes a pair of differentially shielded Geiger-Mueller tubes. The first tube is wrapped in silver foil and the second tube is wrapped in lead foil. B...

L. W. Kruse R. P. McKnight

1984-01-01

124

Underwater optical wireless communication network  

NASA Astrophysics Data System (ADS)

The growing need for underwater observation and subsea monitoring systems has stimulated considerable interest in advancing the enabling technologies of underwater wireless communication and underwater sensor networks. This communication technology is expected to play an important role in investigating climate change, in monitoring biological, biogeochemical, evolutionary, and ecological changes in the sea, ocean, and lake environments, and in helping to control and maintain oil production facilities and harbors using unmanned underwater vehicles (UUVs), submarines, ships, buoys, and divers. However, the present technology of underwater acoustic communication cannot provide the high data rate required to investigate and monitor these environments and facilities. Optical wireless communication has been proposed as the best alternative to meet this challenge. Models are presented for three kinds of optical wireless communication links: (a) a line-of-sight link, (b) a modulating retroreflector link, and (c) a reflective link, all of which can provide the required data rate. We analyze the link performance based on these models. From the analysis, it is clear that as the water absorption increases, the communication performance decreases dramatically for the three link types. However, by using the scattered light it was possible to mitigate this decrease in some cases. It is concluded from the analysis that a high-data-rate underwater optical wireless network is a feasible solution for emerging applications such as UUV-to-UUV links and networks of sensors, and extended ranges in these applications could be achieved by applying a multi-hop concept.

Arnon, Shlomi

2010-01-01

125

Apparatus Notes  

ERIC Educational Resources Information Center

|Describes an oscillating electroscope, an apparatus to verify the time interval between successive events in nuclear decay, and electronic circuits that are the analog of consecutive reactions. (SL)|

Eaton, Bruce G., Ed.

1978-01-01

126

Underwater well installations and handling string joint therefor  

SciTech Connect

Underwater well apparatus in which the handling string for manipulating a handling tool to, E.G., orient and land a multiple string tubing hanger includes a power portion in the form of a single metal piece having a plain cylindrical outer surface to be presented to the blowout protectors, so that orientation of the handling string relative to the protectors is not necessary, and also having through passages for communicating with the tubing strings, and coupling means for attaching the handling tool to the handling string.

Lawson, J.E.

1982-07-20

127

Underwater Laser sensor network: A New Approach for Broadband Communication in the Underwater  

Microsoft Academic Search

In this paper a new approach for the underwater sensor network based on the blue-green laser has been proposed. We describe the application of the underwater sensor network in the undersea exploration, and discuss the difficulties in the traditional the underwater acoustic sensor network. A basic of prototype of underwater laser sensor network has been advanced, which include the architecture

YINGZHUANG LIU; XIAOHU GE

2006-01-01

128

Automatic breath-to-breath analysis of nocturnal polysomnographic recordings  

Microsoft Academic Search

Diagnosis of sleep-disordered breathing is based on the presence of an abnormal breathing pattern during sleep. In this study,\\u000a an algorithm was developed for the offline breath-to-breath analysis of the nocturnal respiratory recordings. For that purpose,\\u000a respiratory signals (nasal airway pressure, thoracic and abdominal movements) were divided into half waves using period amplitude\\u000a analysis. Individual breaths were characterized by the

P. J. van HoudtP; P. P. W. Ossenblok; M. G. van Erp; K. E. Schreuder; R. J. J. Krijn; P. A. J. M. Boon; P. J. M. Cluitmans

2011-01-01

129

Analytical Methods for Breath Investigation  

Microsoft Academic Search

Breath analysis is a non-invasive, painless and attractive diagnostic method without risk to the patients. It has been recommended as a convenient and complementary method for blood and urine analysis. Despite the advantages, breath analysis has not been introduced to medical diagnosis. Only few specific breath tests are available: ethanol in breath after alcohol ingestion, detection of CO2 for diagnosis

Tomasz Ligor

2009-01-01

130

Underwater sensor nodes and networks.  

PubMed

Sensor technology has matured enough to be used in any type of environment. The appearance of new physical sensors has increased the range of environmental parameters for gathering data. Because of the huge amount of unexploited resources in the ocean environment, there is a need of new research in the field of sensors and sensor networks. This special issue is focused on collecting recent advances on underwater sensors and underwater sensor networks in order to measure, monitor, surveillance of and control of underwater environments. On the one hand, from the sensor node perspective, we will see works related with the deployment of physical sensors, development of sensor nodes and transceivers for sensor nodes, sensor measurement analysis and several issues such as layer 1 and 2 protocols for underwater communication and sensor localization and positioning systems. On the other hand, from the sensor network perspective, we will see several architectures and protocols for underwater environments and analysis concerning sensor network measurements. Both sides will provide us a complete view of last scientific advances in this research field. PMID:24013489

Lloret, Jaime

2013-09-05

131

Underwater acoustic sensor networks: research challenges  

Microsoft Academic Search

Underwater sensor nodes will find applications in oceanographic data collection, pollution monitoring, offshore exploration, disaster prevention, assisted navigation and tactical surveillance applications. Moreover, unmanned or autonomous underwater vehicles (UUVs, AUVs), equipped with sensors, will enable the exploration of natural under- sea resources and gathering of scientific data in collaborative monitoring missions. Underwater acoustic networking is the enabling technology for these

Ian F. Akyildiz; Dario Pompili; Tommaso Melodia

2005-01-01

132

Stabilizing underwater vehicle motion using internal rotors  

Microsoft Academic Search

As a case study of a particular control methodology and as a practical contribution in the area of underwater vehicle control, we consider the problem of stabilizing an underwater vehicle using internal rotors as actuators. The control design method comprises three steps. The first step involves shaping the kinetic energy of the conservative dynamics. For the underwater vehicle, the control

Craig A. Woolsey; Naomi Ehrich Leonard

2002-01-01

133

An underwater optical wireless communication network  

Microsoft Academic Search

The growing need for underwater observation and sub-sea monitoring systems has stimulated considerable interest in advancing the enabling technologies of underwater wireless communication and underwater sensor networks. This communication technology is expected to play an important role in investigating climate change, in monitoring biological, bio-geochemical, evolutionary and ecological changes in the sea, ocean and lake environments and in helping to

Shlomi Arnon

2009-01-01

134

Linear optoacoustic underwater communication.  

PubMed

The linear mechanism for optical-to-acoustic energy conversion is explored for optoacoustic communication from an in-air platform or surface vessel to a submerged vessel such as a submarine or unmanned undersea vehicle. The communication range that can be achieved is addressed. A number of conventional signals used in underwater acoustic telemetry applications are shown to be capable of being generated experimentally through the linear optoacoustic regime conversion process. These results are in agreement with simulation based on current theoretical models. A number of practical issues concerning linear optoacoustic communication are addressed that lead to a formulation of a linear-regime optoacoustic communication scheme. The use of oblique laser beam incidence at the air-water interface to obtain considerable in-air range from the laser source to the in-water receiver is addressed. Also, the effect of oblique incidence on in-water range is examined. Next, the optimum and suboptimum linear optoacoustic sound-generation techniques for selecting the optical wavelength and signaling frequency for optimizing in-water range are addressed and discussed. Optoacoustic communication techniques employing M-ary frequency shift keying and multifrequency shift keying are then compared with regard to communication parameters such as bandwidth, data rate, range coverage, and number of lasers employed. PMID:15989059

Blackmon, Fletcher; Estes, Lee; Fain, Gilbert

2005-06-20

135

A case of frog breathing.  

PubMed

Frog breathing (glossopharyngeal breathing) is a useful technique employed to increase ventilation when respiratory muscles are paralysed. It is a technique used by many patients with chronic poliomyelitis, yet many chest physicians and physiotherapists are unfamiliar with this breathing maneuver. Glossopharyngeal breathing coordinates movements of the tongue, cheeks and pharynx to force air from the mouth into the lungs. We report a case of glossopharyngeal breathing, demonstrating a 3 fold increase in vital capacity in a subject with chronic poliomyelitis. PMID:12049135

Moloney, Ed; Doyle, S; Kinahan, J; Burke, C M

2002-03-01

136

UNDERWATER COATINGS FOR CONTAMINATION CONTROL  

SciTech Connect

The Idaho National Laboratory (INL) deactivated several aging nuclear fuel storage basins. Planners for this effort were greatly concerned that radioactive contamination present on the basin walls could become airborne as the sides of the basins became exposed during deactivation and allowed to dry after water removal. One way to control this airborne contamination was to fix the contamination in place while the pool walls were still submerged. There are many underwater coatings available on the market for marine, naval and other applications. A series of tests were run to determine whether the candidate underwater fixatives were easily applied and adhered well to the substrates (pool wall materials) found in INL fuel pools. Lab-scale experiments were conducted by applying fourteen different commercial underwater coatings to four substrate materials representative of the storage basin construction materials, and evaluating their performance. The coupons included bare concrete, epoxy painted concrete, epoxy painted carbon steel, and stainless steel. The evaluation criteria included ease of application, adherence to the four surfaces of interest, no change on water clarity or chemistry, non-hazardous in final applied form and be proven in underwater applications. A proprietary two-part, underwater epoxy owned by S. G. Pinney and Associates was selected from the underwater coatings tested for application to all four pools. Divers scrubbed loose contamination off the basin walls and floors using a ship hull scrubber and vacuumed up the sludge. The divers then applied the coating using a special powered roller with two separate heated hoses that allowed the epoxy to mix at the roller surface was used to eliminate pot time concerns. The walls were successfully coated and water was removed from the pools with no detectable airborne contamination releases.

Julia L. Tripp; Kip Archibald; Ann Marie Phillips; Joseph Campbell

2004-02-01

137

Lecture Notes on Underwater Acoustics.  

National Technical Information Service (NTIS)

This report consists of a set of lecture notes for a course in underwater acoustics, given at the U. S. Naval Air Development Center. The course is based to a considerable extent upon J. W. Horton's book, 'Fundamentals of Sonar,' and covers the following ...

C. L. Bartberger

1965-01-01

138

Underwater explosions and cavitation phenomena  

Microsoft Academic Search

Some aspects of underwater explosions and cavitation phenomena have been studied by using a thermodynamic equation of state for water and a one-dimensional Lagrangian hydrocode. The study showed that surface cavitation is caused by the main blast wave and a bubble pulse from rebound of a release wave moving toward the center of the exploding bubble. Gravity has little effect

Kamegai

1979-01-01

139

Polymer Claw: Instant Underwater Adhesive.  

National Technical Information Service (NTIS)

JHU/APL's Polymer Claw is a pressure-activated underwater adhesive that bonds instantly to biofouled surfaces in a single step. The key to this technology is the use of pressure sensitive microcapsules, which release reactive amine crosslinkers into an ad...

J. J. Benkoski

2012-01-01

140

Underwater Inspection Of Naval Structures  

Microsoft Academic Search

Nondestructive testing (NDT) performed underwater is one of the major maintenance methods to assure the efficient operation of naval structures such as piers, navigational aids, etc. Methods used for NDT of naval structures include general methods such as visual testing, ultrasonics and radiography. Visual testing, supplemented by instruments such as TV cameras and stereo-photography, offers good capability for surface inspection

H. Berger; R. Brackett; J. Mittleman

1983-01-01

141

Research Opportunities in Underwater Acoustics.  

National Technical Information Service (NTIS)

The Naval Studies Board of the National Research Council was asked by the Office of Naval Research (ONR) to establish and oversee a panel to advise on research opportunities with high potential for advancing the science and technology of underwater acoust...

1986-01-01

142

Optimizing ODMRP for underwater networks  

Microsoft Academic Search

Underwater networks have attracted significant attention over the last few years. They can be used in scenarios like environmental monitoring and mine countermeasure but may also be part of modern marine warfare. A prominent example is Anti Submarine Warfare (ASW) with multistatic sonars. These networks may be sparse with potentially long distances between single nodes such that direct communication is

Jan Bauer; Nils Aschenbruck; Raphael Ernst; Elmar Gerhards-Padilla; Peter Martini

2010-01-01

143

Underwater acoustic wireless multiuser communication  

Microsoft Academic Search

The characteristics of shallow water are studied in this paper, including multipath spreading, frequency selective attenuation and so on, which is a guidance for disposing communication modems according to the sound velocity profile to mitigate intersymbol interference (ISI) and to improve the underwater acoustic (UWA) communication range. In order to diminish ISI caused by multipath, Virtual Time Reversal Mirror is

Yin Jingwei; Wang Lei; Chen Kai

2008-01-01

144

Thermotropic Liquid Crystal Film Underwater  

NASA Astrophysics Data System (ADS)

A thermotropic liquid crystal film was produced in distilled water successfully. A lecithin suspension was utilized to make the film. Polarizing microscopic observations were carried out. The molecular arrangement was seemed to be homeotoropic. An expected electrooptic response of the film underwater was confirmed.

Uto, Sadahito; Nakanishi, Yuuji; Matsumoto, Takahumi

2005-05-01

145

Apparatus Review: Cenco Wave Apparatus  

NASA Astrophysics Data System (ADS)

Some apparatus from the 19th century illustrates the phenomena of physics so well that it crops up again in the 21st century. An example is the combined transverse and longitudinal wave machine in Fig. 1. This is in the current Cenco/Sargent-Welch catalog under the name of ``Wave Apparatus'' (Cat. No. WLS-1755-90) and sells for $49.95.

Greenslade, Thomas B.

2009-01-01

146

A miniature optical breathing sensor  

PubMed Central

We demonstrate a novel miniature optical breathing sensor based on an Agarose infiltrated photonic crystal fiber interferometer. The sensor detects the variation in relative humidity that occurs between inhaled and exhaled breath. The sensor interrogation system can determine the breathing pattern in real time and can also predict the breathing rate and the breathing status during respiration. The sensor is suitable for monitoring patients during a magnetic resonance imaging scan where use of sedatives and anesthetics necessitates breathing monitoring; electronic sensors are not suitable in such an environment and a visual observation of the patient's respiratory efforts is often difficult.

Mathew, Jinesh; Semenova, Yuliya; Farrell, Gerald

2012-01-01

147

A miniature optical breathing sensor.  

PubMed

We demonstrate a novel miniature optical breathing sensor based on an Agarose infiltrated photonic crystal fiber interferometer. The sensor detects the variation in relative humidity that occurs between inhaled and exhaled breath. The sensor interrogation system can determine the breathing pattern in real time and can also predict the breathing rate and the breathing status during respiration. The sensor is suitable for monitoring patients during a magnetic resonance imaging scan where use of sedatives and anesthetics necessitates breathing monitoring; electronic sensors are not suitable in such an environment and a visual observation of the patient's respiratory efforts is often difficult. PMID:23243581

Mathew, Jinesh; Semenova, Yuliya; Farrell, Gerald

2012-11-26

148

Breathing: Rhythmicity, Plasticity, Chemosensitivity  

PubMed Central

Breathing is a vital behavior that is particularly amenable to experimental investigation. We review recent progress on three problems of broad interest. (i) Where and how is respiratory rhythm generated? The preBtzinger Complex is a critical site, whereas pacemaker neurons may not be essential. The possibility that coupled oscillators are involved is considered. (ii) What are the mechanisms that underlie the plasticity necessary for adaptive changes in breathing? Serotonin-dependent long-term facilitation following intermittent hypoxia is an important example of such plasticity, and a model that can account for this adaptive behavior is discussed. (iii) Where and how are the regulated variables CO2 and pH sensed? These sensors are essential if breathing is to be appropriate for metabolism. Neurons with appropriate chemosensitivity are spread throughout the brainstem; their individual properties and collective role are just beginning to be understood.

Feldman, Jack L.; Mitchell, Gordon S.; Nattie, Eugene E.

2010-01-01

149

Breathing, voice, and movement therapy: Applications to breathing disorders  

Microsoft Academic Search

Elsa Gindler (18851961) developed a holistic approach to the human body and psyche via the movement of breath. Gindler experimented with movements to strengthen the deeper layers of the muscular system and improve the circulation of oxygen, movements that reduced tensions that had been preventing the breathing muscles from functioning properly. Subsequently, she founded a school for breathing and body

Imke Buchholz

1994-01-01

150

[Techniques of underwater intervention: means, methods, research and outlook].  

PubMed

In France, diving activities are practised by a large number of people, included recreational or sport divers, commercial and military divers. Different diving technics are used, depending on depth and duration of underwater interventions: human intervention under pressure (diving), one atmosphere submarine, remotely operated vehicle (ROV). The diver used specific equipment and procedures with air, heliox (oxygen -helium), hydrox (oxygen-hydrogen) or hydreliox (oxygen-hydrogen-helium) breathing gas mixtures; and for decompression, specific tables adapted to gas mixtures and underwater time exposures. In 1988, six Comex and French Navy divers worked at a record depth of 534 msw with hydreliox and in 1992 a world record onshore dive at 701 msw was performed by Comex in Marseille. These dives showed the efficiency of hydrogen diving at very deep depth. Among a lot of submarines built for undersea works, the latest in the range of Comex's innovative submarines, the "Remora 2000" combines the functions and instrumentation of an oceanographic subsea vessel with eye catching design of a recreational submarine. Now, ROV's replace more and more the diver on oil subsea offshore fields. PMID:8963715

Gardette, B; Delauze, H G

1996-05-01

151

Diver Education Series: Tethered Scuba Diving.  

National Technical Information Service (NTIS)

Swimming and working underwater using self-contained underwater breathing apparatus (scuba) is a standard practice in military, scientific, and recreational diving. Accepted safety procedures for scuba diving operations generally require deployment of div...

L. H. Somers

1986-01-01

152

Irradiation apparatus  

DOEpatents

An apparatus for introducing ionizing radiation into compressed gas insulation systems, such as high-voltage generators or transmission lines to smooth out electrical discontinuities, particularly those caused by foreign particulates that produce high gradients, and to increase the voltage holding capability of the system is described. The apparatus of the invention may also be used to regulate and stabilize the voltage of the system by varying the amount of applied load. A corona discharge device may also be used in conjunction with the invention. (Official Gazette)

Goldie, C.H.; Fernald, R.A.

1974-01-29

153

Positioning apparatus  

DOEpatents

An apparatus is provided for precisely adjusting the position of an article relative to a beam emerging from a neutron source disposed in a housing. The apparatus includes a support pivotably mounted on a movable base plate and freely suspended therefrom. The support is gravity biased toward the housing and carries an article holder movable in a first direction longitudinally of the axis of said beam and normally urged into engagement against said housing. Means are provided for moving the base plate in two directions to effect movement of the suspended holder in two mutually perpendicular directions, respectively, normal to the axis of the beam.

Vogel, M.A.; Alter, P.

1983-07-07

154

Ion-trap detection of volatile organic compounds in alveolar breath  

SciTech Connect

We describe a method for the collection and microanalysis of the volatile organic compounds in human breath. A transportable apparatus supplies subjects with purified air and samples their alveolar breath; the volatile organic compounds are captured in an adsorptive trap containing activated carbon and molecular sieve. The sample is thermally desorbed from the trap in an automated microprocessor-controlled device, concentrated by two-stage cryofocusing, and assayed by gas chromatography with ion-trap detection. Compounds are identified by reference to a computer-based library of mass spectra with subtraction of the background components present in the inspired air. We used this device to study 10 normal subjects and determined the relative abundance of the volatile organic compounds in their alveolar breath. The breath-collecting apparatus was convenient to operate and was well tolerated by human volunteers.

Phillips, M.; Greenberg, J. (Department of Medicine, St. Vincent's Medical Center of Richmond, Staten Island, NY (United States))

1992-01-01

155

Dont Breathe the Moondust  

NSDL National Science Digital Library

This NASA site describes how an Apollo caught "lunar dust hay fever and how breathing lunar dust poses a serious health risk. The site contains several images of lunar dust. In addition, the even more serious hazard of dust on Mars is presented.

2008-04-25

156

What Causes Bad Breath?  

MedlinePLUS

... Some sugar-free gums and mints can temporarily mask odors, too. If you brush and floss properly and visit your dentist for regular cleanings, but your bad breath persists, you may have a medical problem like sinusitis or gum disease . Call your ...

157

The Breath of Life  

Microsoft Academic Search

All animal life in Chesapeake Bay, from the worms that inhabit its muddy bottom, to the fish and crabs found in its rivers, to the people that live on its land, need oxygen to survive. We breathe oxygen, which lets us extract energy from the food we eat. Our bodies use this energy to function. This process is essentially the

CHESAPEAKE BAY

1916-01-01

158

Apparatus Notes.  

ERIC Educational Resources Information Center

This collection of notes describes (1) an optoelectronic apparatus for classroom demonstrations of mechanical laws, (2) a more efficient method for demonstrated nuclear chain reactions using electrically energized "traps" and ping-pong balls, and (3) an inexpensive demonstration for qualitative analysis of temperature-dependent resistance. (CS)

Eaton, Bruce G., Ed.

1980-01-01

159

Radiography apparatus  

Microsoft Academic Search

Radiography apparatus including radiation generating means, collimator means interposed between the radiation generating means and an object to be exposed to radiation, scintillator means disposed on the opposite side of the object from the radiation generating means for converting the radiation to light, a self-scanning, integrated array of photodiodes for receiving light and emitting responsive electrical signals, optical coupling means

D. Sashin; E. J. Sternglass

1979-01-01

160

Apparatus Reviews.  

ERIC Educational Resources Information Center

|Reviews apparatus design and instructional uses for Fume Cupboard Monitor, Plant Tissue Culture Kit, various equipment for electronic systems course, Welwyn Microprocessor-Tutor, Sweep Function Generator SFG 606, and Harris manufacturers materials--Regulated Power Supply Units, Electronic Current and Voltage Meters, Gas Preparation Kit, and

School Science Review, 1981

1981-01-01

161

Apparatus Reviews.  

ERIC Educational Resources Information Center

|Provided are reviews of science equipment/apparatus. Items reviewed include: Harris Micro-ecology tubes; Harris chromosome investigation kit; Harris trycult slides; a pressure cooker with thermometer; digital pH meter; digital scaler timer; electrical compensation calorimeter; and Mains alternating current ammeter. (JN)|

School Science Review, 1983

1983-01-01

162

Apparatus Reviews.  

ERIC Educational Resources Information Center

|Describes some science apparatus: included are a gene kit to demonstrate aspects of population genetics and selection, an electronic thermometer for use in the field of environmental studies, an astrobrella to use in astronomy classes, and crystal display models of different substances for chemistry classes. (GA)|

School Science Review, 1978

1978-01-01

163

The underwater video system VIS  

Microsoft Academic Search

An underwater video system (Video In Situ: VIS) is described that determines sizes and settling velocities of suspended mud flocs in situ, without disturbing large fragile aggregates. Some results are presented from the Ems estuary, showing macroflocs of 200 to 700 ?m (up to 1 mm) diameter with settling velocities in the range of 0.5 to 8 mms?1. They survived

Wim van Leussen; John M. Cornelisse

1996-01-01

164

High bandwidth underwater optical communication  

Microsoft Academic Search

We report error-free underwater optical transmission measurements at 1 Gbit\\/s (109 bits\\/s) over a 2 m path in a laboratory water pipe with up to 36 dB of extinction. The source at 532 nm was derived from a 1064 nm continuous-wave laser diode that was intensity modulated, amplified, and frequency doubled in periodically poled lithium niobate. Measurements were made over

Frank Hanson; Stojan Radic

2008-01-01

165

The Museum of Underwater Archaeology  

NSDL National Science Digital Library

One of the goals of the University of Rhode Island's Museum of Underwater Archaeology (MUA) is to help "underwater archaeologists present their research to the general public by creating web based museum style exhibits as well as announce their latest projects." Exploring the website "by map" allows visitors to see the locations of projects. Visitors can then click on an anchor, which will give a brief description of the project, and this also provides a link to see the corresponding journal, or just to read more about the project. The featured exhibit, under "Exhibits" on the homepage, is "ECU's [East Carolina University] Shipwrecks in Bermuda The 2008 Field School". The students can be seen in a photo slideshow on the introductory page of the exhibit. In the "Findings" section of the exhibit is a link to "Underwater Jigsaw Puzzle", which sounds like a game, but is the outline of all the debris at a ship breaking site. When more than one ship is found at a ship breaking site, the site plan helps maritime archaeologists decipher which pieces belong to which ship. It can be confusing and challenging, and is not always successful.

166

Underwater Coatings for Contamination Control  

SciTech Connect

The Idaho National Engineering and Environmental Laboratory (INEEL) is deactivating several fuel storage basins. Airborne contamination is a concern when the sides of the basins are exposed and allowed to dry during water removal. One way of controlling this airborne contamination is to fix the contamination in place while the pool walls are still submerged. There are many underwater coatings available on the market that are used in marine, naval and other applications. A series of tests were run to determine whether the candidate underwater fixatives are easily applied and adhere well to the substrates (pool wall materials) found in INEEL fuel pools. The four pools considered included 1) Test Area North (TAN-607) with epoxy painted concrete walls; 2) Idaho Nuclear Technology and Engineering Center (INTEC) (CPP-603) with bare concrete walls; 3) Materials Test Reactor (MTR) Canal with stainless steel lined concrete walls; and 4) Power Burst Facility (PBF-620) with stainless steel lined concrete walls on the bottom and epoxy painted carbon steel lined walls on the upper portions. Therefore, the four materials chosen for testing included bare concrete, epoxy painted concrete, epoxy painted carbon steel, and stainless steel. The typical water temperature of the pools varies from 55oF to 80oF dependent on the pool and the season. These tests were done at room temperature. The following criteria were used during this evaluation. The underwater coating must: Be easy to apply Adhere well to the four surfaces of interest Not change or have a negative impact on water chemistry or clarity Not be hazardous in final applied form Be proven in other underwater applications. In addition, it is desirable for the coating to have a high pigment or high cross-link density to prevent radiation from penetrating. This paper will detail the testing completed and the test results. A proprietary two-part, underwater epoxy owned by S. G. Pinney and Associates was selected to be applied by divers after scrubbing loose contamination off the basin walls and floors using a ship hull scrubber and vacuuming up the sludge. A special powered roller with two separate heated hoses that allowed the epoxy to mix at the roller surface was used to eliminate pot time concerns. The walls were successfully coated and water was removed from the pool with no airborne contamination problems.

Julia L. Tripp; Kip Archibald; Ann-Marie Phillips; Joseph Campbell

2004-02-01

167

Sampling apparatus  

DOEpatents

A sampling apparatus is provided for sampling substances from solid surfaces. The apparatus includes first and second elongated tubular bodies which telescopically and sealingly join relative to one another. An absorbent pad is mounted to the end of a rod which is slidably received through a passageway in the end of one of the joined bodies. The rod is preferably slidably and rotatably received through the passageway, yet provides a selective fluid tight seal relative thereto. A recess is formed in the rod. When the recess and passageway are positioned to be coincident, fluid is permitted to flow through the passageway and around the rod. The pad is preferably laterally orientable relative to the rod and foldably retractable to within one of the bodies. A solvent is provided for wetting of the pad and solubilizing or suspending the material being sampled from a particular surface.

Gordon, Norman R. (Kennewick, WA); King, Lloyd L. (Benton, WA); Jackson, Peter O. (Richland, WA); Zulich, Alan W. (Bel Air, MD)

1989-01-01

168

Hyperthermia apparatus  

DOEpatents

A hyperthermia apparatus, suitable for transurethral application, has an energy radiating element comprising a leaky-wave antenna. The leaky wave antenna radiation pattern is characterized by a surface wave which propagates along an aperture formed by openings (small in comparison to a wavelength) in the outer conductor of a transmission line. Appropriate design of the leaky wave antenna produces a uniform, broadside pattern of temperature elevation that uniformly heats all or part of the periurethral tissues.

Larsen, Lawrence E. (Albuquerque, NM)

2000-01-01

169

Valve apparatus  

SciTech Connect

A description is given of a valve apparatus for use in subterranean well and carriable on a fluid transmission conduit insertable therein, comprising: ball valve head means having camway slot means defined exteriorly theron; valve seat means having camway ball means secured thereto and carriable in said camway slot means to pivot said valve head means on said seat means to shift said appartus between open and closed positions in response to manipulation of said fluid transmission conduit.

McStravick, D.; Roberts, W.

1980-07-01

170

42 CFR 84.94 - Gas flow test; closed-circuit apparatus.  

Code of Federal Regulations, 2012 CFR

...Self-Contained Breathing Apparatus § 84.94 Gas flow test; closed-circuit apparatus. (a) Where oxygen is supplied by a constant-flow device only, the rate of flow shall be at least 3 liters per minute for the...

2012-10-01

171

42 CFR 84.94 - Gas flow test; closed-circuit apparatus.  

Code of Federal Regulations, 2011 CFR

...Self-Contained Breathing Apparatus § 84.94 Gas flow test; closed-circuit apparatus. (a) Where oxygen is supplied by a constant-flow device only, the rate of flow shall be at least 3 liters per minute for the...

2011-10-01

172

The underwater environment: cardiopulmonary, thermal, and energetic demands.  

PubMed

Water covers over 75% of the earth, has a wide variety of depths and temperatures, and holds a great deal of the earth's resources. The challenges of the underwater environment are underappreciated and more short term compared with those of space travel. Immersion in water alters the cardio-endocrine-renal axis as there is an immediate translocation of blood to the heart and a slower autotransfusion of fluid from the cells to the vascular compartment. Both of these changes result in an increase in stroke volume and cardiac output. The stretch of the atrium and transient increase in blood pressure cause both endocrine and autonomic changes, which in the short term return plasma volume to control levels and decrease total peripheral resistance and thus regulate blood pressure. The reduced sympathetic nerve activity has effects on arteriolar resistance, resulting in hyperperfusion of some tissues, which for specific tissues is time dependent. The increased central blood volume results in increased pulmonary artery pressure and a decline in vital capacity. The effect of increased hydrostatic pressure due to the depth of submersion does not affect stroke volume; however, a bradycardia results in decreased cardiac output, which is further reduced during breath holding. Hydrostatic compression, however, leads to elastic loading of the chest wall and negative pressure breathing. The depth-dependent increased work of breathing leads to augmented respiratory muscle blood flow. The blood flow is increased to all lung zones with some improvement in the ventilation-perfusion relationship. The cardiac-renal responses are time dependent; however, the increased stroke volume and cardiac output are, during head-out immersion, sustained for at least hours. Changes in water temperature do not affect resting cardiac output; however, maximal cardiac output is reduced, as is peripheral blood flow, which results in reduced maximal exercise performance. In the cold, maximal cardiac output is reduced and skin and muscle are vasoconstricted, resulting in a further reduction in exercise capacity. PMID:19036887

Pendergast, D R; Lundgren, C E G

2008-11-26

173

Mechanized underwater welding and cutting for VLFS  

Microsoft Academic Search

Mechanized underwater welding and cutting techniques are very important for actual usage of very large floating structures (VLFS). On-site welding plays a major part in the construction process. The total weld line is very long and a half part is submerged under water. The water curtain type wet underwater welding technique had shown its excellent ability for the construction of

Yoji OGAWA

2002-01-01

174

Moving mass control for underwater vehicles  

Microsoft Academic Search

We present two reduced-dimensional, noncanonical Hamiltonian models for a neutrally buoyant underwater vehicle coupled to an internal moving mass. It is expected that these models will be useful in designing nonlinear control laws for underwater gliders as well as for spacecraft, atmospheric re-entry vehicles, and other vehicles which use internal moving mass actuators. To illustrate, we investigate stability of a

C. A. Woolsey; N. E. Leonard

2002-01-01

175

Software Modems for Underwater Sensor Networks  

Microsoft Academic Search

The prohibitive monetary cost and high power consumption of existing acoustic hardware represent an obstacle for underwater sensor network deployment efforts. To address this issue, we propose underwater networks that rely on widely available speakers and microphones in electronic devices, coupled with software modems, to establish acoustic communication links. In this paper, we analytically and empirically explore the potential of

Raja Jurdak; P. Aguiar; P. Baldi; C. V. Lopes

2007-01-01

176

Pressure Routing for Underwater Sensor Networks  

Microsoft Academic Search

A SEA Swarm (Sensor Equipped Aquatic Swarm) is a sensor cloud that drifts with water currents and enables 4D (space and time) monitoring of local underwater events such as contaminants, marine life and intruders. The swarm is escorted at the surface by drifting sonobuoys that collect the data from underwater sensors via acoustic modems and report it in real- time

Uichin Lee; Paul Wang; Youngtae Noh; Luiz Filipe M. Vieira; Mario Gerla; Jun-Hong Cui

2010-01-01

177

A MAC Protocol for Underwater Sensor Networks  

Microsoft Academic Search

There exists an increasing demand for reliable, high capacity underwater sensor networks. Application interests include oceanographic information acquiring, environmental monitoring, and coastal defense. A multi-channel media access control (MAC) protocol used for underwater acoustic channel which improves the network efficiency by using RTS-CTS exchange is presented. Simulation tests on OPNET modeler show that, its network communication performance is satisfactory.

Meng Tao; Shi Haoshan; Wang Yu

2007-01-01

178

Cooperative positioning in underwater sensor networks  

Microsoft Academic Search

We consider cooperative positioning using acoustic range measurements for underwater sensor networks, including networks formed by autonomous unmanned underwater vehicles (UUVs). Severe multipath scattering from the seabed and ocean surface can result in inaccurate range measurements. In an inhomogeneous medium, such as sea water, the direct path is not necessarily the strongest path or the first arrival. Then, the range

Xing Tan; Jian Li

2010-01-01

179

Design of a flapping foil underwater vehicle  

Microsoft Academic Search

The design, construction and testing of a biomimetic flapping foil autonomous underwater vehicle are detailed. The project is a proof of concept for the use of flapping foils as the sole source of propulsion for an underwater vehicle. We intend to use the vehicle in several physical arrangements to compare the swimming performance of different shapes and foil arrangements. The

Stephen Licht; Franz Hover; Michael S. Triantafyllou

2004-01-01

180

NEW METHODS OF UNDERWATER SHIP NOISE CLASSIFICATION  

Microsoft Academic Search

The detection, classification, identification and recognition ships noise features have been of the highest importance for scientific and also defense interest. A big effort is made in the passive sonar technologies that allow applying underwater noise for practical purpose. Results are presented which demonstrate the ability of the network to classify man made sources as are underwater ships noise. The

EUGENIUSZ KOZACZKA

181

Nonlinear tracking control of autonomous underwater vehicles  

Microsoft Academic Search

Discusses 3D motion of underwater vehicles. The authors describe kinematics of an underwater vehicle by six state variables and four inputs, and use a Lyapunov-like function to develop a nonlinear tracking control scheme. The control method effectively makes use of the nonholonomic nature of the system. Simulation results agreed with the theoretical predictions and confirmed the usefulness of the proposed

Yoshihiko Nakamura; Shrikant Savant

1992-01-01

182

Seeking Teachers for Underwater Robotics PD Program  

ERIC Educational Resources Information Center

|With funding from the National Science Foundation (NSF), ITEEA members will contribute to the development of a hybrid professional development program designed to facilitate the scale-up of an innovative underwater robotics curriculum. WaterBotics[TM] is an underwater robotics curriculum that targets students in middle and high school classrooms

McGrath, Beth; Sayres, Jason

2012-01-01

183

Monitoring Underwater Sensors with an Amphibious Robot  

Microsoft Academic Search

The underwater domain provides a wide range of potential applications for autonomous systems. Sessile (im- mobile) sensor platforms can provide a sensing network to monitor a range of different underwater events. Monitoring such networks can be a challenge, however, as the sensor nodes can be difficult to monitor and the nature of the medium limits wireless communication. Here we describe

Andrew Speers; Anna Topol; James Zacher; Robert Codd-Downey; Bart Verzijlenberg; Michael Jenkin

2011-01-01

184

An eigenpath underwater acoustic communication channel model  

Microsoft Academic Search

Ocean exploration can require high data rate transmission over an underwater acoustic channel. The properties of underwater acoustic channels are thus very important in the design of high data rate acoustic telemetry systems. The authors review the essential properties of such channels. Based on some experimental results and analytical considerations they point out the limitations of the Rayleigh fading model

Xueyi Geng; Adam Zielinski

1995-01-01

185

Adaptive Data Broadcasting in Underwater Wireless Networks  

Microsoft Academic Search

Underwater acoustic networks have recently emerged as a new area of research in wireless networking. These networks can support a large number of applications such as environmental and underwater equipment monitoring. In recent years, there has been substantial work on protocol design for these networks with most efforts focusing on MAC and network layer protocols. Despite being a fundamental networking

Petros Nicopolitidis; Georgios I. Papadimitriou; Andreas S. Pomportsis

2010-01-01

186

Impacts of optical turbulence on underwater imaging  

Microsoft Academic Search

Optical signal transmission underwater is of vital interests to both civilian and military applications. The range and signal to noise during the transmission, as a function of system and water optical properties determines the effectiveness of EO technology. These applications include diver visibility, search and rescue, mine detection and identification, and optical communications. The impact of optical turbulence on underwater

Weilin Hou; S. Woods; W. Goode; E. Jarosz; A. Weidemann

2011-01-01

187

Optical propagation in the underwater environment  

Microsoft Academic Search

Similar to atmospheric propagation, the propagation of light underwater is affected by absorption and scattering. However, the scale of absorption and scattering in the underwater environment is much shorter, with extinction coefficients given in inverse meters rather than inverse kilometers. Such severe attenuation of light poses many challenges to optical imaging and free space optical communications in water. Although blue-green

Linda Mullen

2009-01-01

188

High density underwater fiber optic systems security  

Microsoft Academic Search

The underwater telecommunications industry is rebounding from unused fiber optic capacity installed prior to the collapse of the telecommunications marketplace. Dark fiber will be equipped in the next 18 months to meet forecasted demands for 2004 and beyond. World events have increased the demand for secure high bandwidth underwater fiber optic communications, and at the same time the telecommunications service

Robert Bannon; D. Burnett

2002-01-01

189

Underwater Glider Model Parameter Identication  

Microsoft Academic Search

An underwater glider is a buoyancy-propelled, xed- wing vehicle with attitude controlled completely, or in part, by means of internal mass redistribution. We have developed a physics-based nonlinear model of the dynamics of an underwater glider and adapted it to model the SLOCUM glider's geometry, rudder, ballast pump and internal movable mass. In this paper we identify the model parameters

Joshua G. Graver; Ralf Bachmayer; Naomi Ehrich; David M. Fratantoni

2003-01-01

190

Analysis of an Autonomous Underwater Glider  

Microsoft Academic Search

Underwater gliders have proven to be a powerful tool in oceanography because they are reusable, inexpensive and achieve a high duration. These qualities have made the acquisition of oceanographic data sets more accessible. The purpose of this article is to present a study aimed at modelling an underwater glider in the longitudinal and lateral plane. The proposed glider possesses a

Asher Bender; Daniel Matthew Steinberg; Ariell Lee Friedman; Stefan B. Williams

191

Effect of influenza vaccination on oxidative stress products in breath.  

PubMed

Viral infections cause increased oxidative stress, so a breath test for oxidative stress biomarkers (alkanes and alkane derivatives) might provide a new tool for early diagnosis. We studied 33 normal healthy human subjects receiving scheduled treatment with live attenuated influenza vaccine (LAIV). Each subject was his or her own control, since they were studied on day 0 prior to vaccination, and then on days 2, 7 and 14 following vaccination. Breath volatile organic compounds (VOCs) were collected with a breath collection apparatus, then analyzed by automated thermal desorption with gas chromatography and mass spectroscopy. A Monte Carlo simulation technique identified non-random VOC biomarkers of infection based on their C-statistic values (area under curve of receiver operating characteristic). Treatment with LAIV was followed by non-random changes in the abundance of breath VOCs. 2, 8-Dimethyl-undecane and other alkane derivatives were observed on all days. Conservative multivariate models identified vaccinated subjects on day 2 (C-statistic = 0.82, sensitivity = 63.6% and specificity = 88.5%); day 7 (C-statistic = 0.94, sensitivity = 88.5% and specificity = 92.3%); and day 14 (C-statistic = 0.95, sensitivity = 92.3% and specificity = 92.3%). The altered breath VOCs were not detected in live attenuated influenza vaccine, excluding artifactual contamination. LAIV vaccination in healthy humans elicited a prompt and sustained increase in breath biomarkers of oxidative stress. A breath test for these VOCs could potentially identify humans who are acutely infected with influenza, but who have not yet developed clinical symptoms or signs of disease. PMID:21383469

Phillips, Michael; Cataneo, Renee N; Chaturvedi, Anirudh; Danaher, Patrick J; Devadiga, Anantrai; Legendre, David A; Nail, Kim L; Schmitt, Peter; Wai, James

2010-01-22

192

Restoration of turbulence degraded underwater images  

NASA Astrophysics Data System (ADS)

The ability to image underwater is highly desired for scientific and military applications, including optical communications, submarine awareness, diver visibility, and mine detection. Underwater imaging is severely impaired by scattering and optical turbulence associated with refractive index fluctuations. This work introduces a novel approach to restoration of degraded underwater imagery based on a multi-frame correction technique developed for atmospheric distortions. The method represents synthesis of ``lucky-region'' fusion with nonlinear gain and optical flow-based image warping. The developed multiframe image restoration algorithm is tested on underwater imagery collected in a laboratory tank and in a field exercise. Reliance of image restoration on accuracy of the optical flow algorithm is revealed. The developed algorithm demonstrates significant resolution improvement of the restored image in comparison to any single frame or the mean of the underwater image sequence.

Kanaev, Andrey V.; Hou, Weilin; Woods, Sarah; Smith, Leslie N.

2012-05-01

193

The optical monitor system of anti-phobic raid underwater  

Microsoft Academic Search

The underwater security system, used in the Qingdao sailboat game of 2008 Olympic Games, combined multiple underwater cameras with sonar detectors, forms an underwater barrier, which can observe the movement of suspicious objects and get the underwater video images continuously and instantly. The lighting system can provide sufficient illumination matched with target to reach the best imaging result. The whole

Chengdong Zheng; Yan-Sheng Weng; Xi-Zhan Liu

2009-01-01

194

State Estimation Strategies for Autonomous Underwater Vehicle Fish Tracking Applications  

Microsoft Academic Search

Abstract As the largest unexplored area on earth, the underwater world has unlimited at- traction to marine scientists. Due to the complexity of the underwater environment and the limitations of human divers, underwater exploration has been facilitated by the use of submarines, Remotely Operated Vehicles (ROVs) and Autonomous Underwater Vehicles (AUVs). In recent years, use of autonomous control systems being

Jun Zhou

2007-01-01

195

Basic Research on Underwater Docking of Elexible Structures  

Microsoft Academic Search

Deals with basic research on underwater docking of flexible underwater structures using an active control system. The actively controlled underwater docking has such potentials on the installation or construction of underwater structures at deep water depth that the structures can be installed precisely on the desired point of seabed. For very large structure automated construction, it can be possible to

Keisuke Watanabe; Hideyuki Suzuki; Qi Tao; Koichiro Yoshida

1998-01-01

196

Underwater Optical Wireless Channel Modeling Using Monte-Carlo Method  

Microsoft Academic Search

At present, there is a lot of interest in the functioning of the marine environment. Unmanned or Autonomous Underwater Vehicles (UUVs or AUVs) are used in the exploration of the underwater resources, pollution monitoring, disaster prevention etc. Underwater, where radio waves do not propagate, acoustic communication is being used. But, underwater communication is moving towards Optical Communication which has higher

P. Sri Saini; Shanthi Prince

2011-01-01

197

75 FR 61386 - Emergency Escape Breathing Apparatus Standards  

Federal Register 2010, 2011, 2012, 2013

...non-flammable, nonpoisonous compressed gases; gases poisonous...that convenient storage be provided for...non-flammable, nonpoisonous compressed gas--including...packaging, including a tank car, after its...Caboose; (10) Tank car; and (11...2) Is on a storage track and its...

2010-10-05

198

Breathing patterns. 1. Normal subjects.  

PubMed

Ventilatory monitoring devices that require mouthpiece breathing produce a rise in tidal volume (VT), a fall in frequency (f) and alterations in periodicity and variability of breathing components. Together with the introduction of the respiratory inductive plethysmograph, a reliable noninvasive monitoring device of ventilation, major advances have taken place in understanding the significance of the components of the breathing pattern. We measured the breathing pattern of normal subjects utilizing respiratory inductive plethysmography and continuously processed these data with a microprocessor system. The mean values of the breathing pattern components in normal subjects were not affected by age, but the rhythmicity was more irregular in the elderly. The values of breathing pattern components obtained noninvasively by respiratory inductive plethysmography in normal subjects are fairly predictable in limits similar to other tests of pulmonary function. PMID:6872603

Tobin, M J; Chadha, T S; Jenouri, G; Birch, S J; Gazeroglu, H B; Sackner, M A

1983-08-01

199

29 CFR 1910.402 - Definitions.  

Code of Federal Regulations, 2013 CFR

... A pressure vessel for the storage of gases. Decompression...underwater apparatus which supplies compressed breathing gas at the ambient...from the dive location with compressed air for breathing. Treatment...the dive location. Volume tank: A pressure vessel...

2013-07-01

200

1. Modelling of Underwater Robots  

Microsoft Academic Search

1.1 Introduction 1.2 Rigid Body's Kinematics 1.2.1 Attitude representation by Euler angles 1.2.2 Attitude representation by quaterion 1.2.3 Attitude error representation 1.3 Rigid Body's Dynamics 1.3.1 Rigid body's dynamics in matrix form 1.4 Hydrodynamic Effects 1.4.1 Added mass and inertia 1.4.2 Damping effects 1.4.3 Current effects 1.5 Gravity and Buonancy 1.6 Thrusters' Dynamics 1.7 Underwater Vehicle's Dynamics in Matrix Form

Gianluca Antonelli

201

Detonating apparatus  

DOEpatents

1. Apparatus for detonation of high explosive in uniform timing comprising in combination, an outer case, spark gap electrodes insulatedly supported in spaced relationship within said case to form a spark gap, high explosive of the class consisting of pentaerythritol tetranitrate and trimethylene trinitramine substantially free from material sensitive to detonation by impact compressed in surrounding relation to said electrodes including said spark gap under a pressure from about 100 psi to about 500 psi, said spark gap with said compressed explosive therein requiring at least 1000 volts for sparking, and means for impressing at least 1000 volts on said spark gap.

Johnston, Lawrence H. (Minneapolis, MN)

1976-01-01

202

SEPARATION APPARATUS  

DOEpatents

A furnace apparatus is designed for treating a nuclear reactor waste solution. The solution is sprayed onto a bed of burning petroleum coke which expels water, the more volatile fission products, and nitrogen oxides. Next, chlorine gas is introduced from below which causes aluminum to volatilize as aluminum chloride and along with it certain fission products including Nb/sup 95/ and Zr/sup 95/. These lose their radioactivity within four years and the long- lived radioactivity remains with the ash, which is stored. (AEC) V) nitrate. (P.C.H.)

Huff, J.B.

1962-03-13

203

Heating apparatus  

SciTech Connect

This patent describes a heating apparatus. It comprises a housing, means for introducing water to a plurality of water conduits of the housing, a fireplace compartment disposed within the housing, the fireplace compartment being provided with a burner, a fin coil member disposed in the upper portion of the housing and communicating with the room environment for heat emitting, the fin coil member containing a serpentine configured fin coils disposed therein for absorbing heat from the water disposed in the water conduits, a heat chamber containing the water conduits, the heat chamber connected at one end to the fireplace compartment and at the other end to a chimney disposed at the middle of the the fireplace compartment for circulating hot combustion gases therethrough and for heating the water disposed in the water conduits, the combustion gases being vented from the chimney, and at least four turbo fans communicating with the heat chamber for blowing air across the fin coil member so as to heat the air and discharge it to the room environment, and reduce noise pollution of the heating apparatus.

Woo, C.G.

1991-07-30

204

Polarimetric imaging of underwater targets  

NASA Astrophysics Data System (ADS)

Underwater imaging is challenging because of the significant attenuation of light due to absorption and scattering of light in water. Using polarization properties of light is one of the options for improving image quality. We present results of imaging of a polarized target in open ocean (Curacao) and coastal (NY Bight) waters. The target in the shape of a square is divided into several smaller squares, each of which is covered with a polarizing film with different polarization orientations or transmission coefficients was placed on a mirror and imaged under water by a green-band full-Stokes polarimetric video camera at the full range of azimuth angles against the Sun. The values of the Stokes vector components from the images are compared with the modeled image of the target using radiative transfer code for the atmosphere-ocean system combined with the simple imaging model. It is shown that even in clear water the impact of the water body on the polarized underwater image is very significant and retrieval of target polarization characteristics from the image is extremely challenging.

Gilerson, Alex; Carrizo, Carlos; Tonizzo, Alberto; Ibrahim, Amir; El-Habashi, Ahmed; Foster, Robert; Ahmed, Samir

2013-06-01

205

Rebreathing TLCO versus Single Breath TLCO at Different Degrees of Unequal Ventilation  

Microsoft Academic Search

The influence of unequal ventilation on the differences between the rebreathing (RB) and the single breath (SB) measurement of the transfer factor of the lung for carbon monoxide (TLCO) was investigated. An apparatus was developed which measured both TLCORB and TLCOSB. Unequal ventilation increases with lung volume, caused by the combined effect of increasing ratio of total volume to RV

H. Jansons; J. K. Fokkens; I. van der Tweel; J. Kreukniet

1994-01-01

206

Living with Dyspnea -- How to Breathe Easier  

MedlinePLUS

Living with DyspneaHow to breathe easier Dyspnea (pronounced dispNEEuh) is a medical term for ... Stand still and breathe in. Patient Education 1 Living with DyspneaHow to breathe easier 2. Walk ...

207

AURP: an AUV-aided underwater routing protocol for underwater acoustic sensor networks.  

PubMed

Deploying a multi-hop underwater acoustic sensor network (UASN) in a large area brings about new challenges in reliable data transmissions and survivability of network due to the limited underwater communication range/bandwidth and the limited energy of underwater sensor nodes. In order to address those challenges and achieve the objectives of maximization of data delivery ratio and minimization of energy consumption of underwater sensor nodes, this paper proposes a new underwater routing scheme, namely AURP (AUV-aided underwater routing protocol), which uses not only heterogeneous acoustic communication channels but also controlled mobility of multiple autonomous underwater vehicles (AUVs). In AURP, the total data transmissions are minimized by using AUVs as relay nodes, which collect sensed data from gateway nodes and then forward to the sink. Moreover, controlled mobility of AUVs makes it possible to apply a short-range high data rate underwater channel for transmissions of a large amount of data. To the best to our knowledge, this work is the first attempt to employ multiple AUVs as relay nodes in a multi-hop UASN to improve the network performance in terms of data delivery ratio and energy consumption. Simulations, which are incorporated with a realistic underwater acoustic communication channel model, are carried out to evaluate the performance of the proposed scheme, and the results indicate that a high delivery ratio and low energy consumption can be achieved. PMID:22438740

Yoon, Seokhoon; Azad, Abul K; Oh, Hoon; Kim, Sunghwan

2012-02-09

208

Palliative care - shortness of breath  

MedlinePLUS

Dyspnea - end-of-life ... of breath is a common symptom at the end of life. Talk with your doctors and nurses so you are prepared if it occurs. At the end of life, it is common to feel short of breath. ...

209

Submarines, spacecraft and exhaled breath  

Microsoft Academic Search

ForewordThe International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled breath. What may have escaped our notice is a complementary field of research that explores the creation and maintenance of

Joachim D Pleil; Armin Hansel

2012-01-01

210

Shortness of Breath and Eating  

MedlinePLUS

... Nutrition Reflux and Lung Disease Back-to-School Nutrition Tips Proper Hydration Sodium Dangers Plant-Based Diets Make an appointment Ask a Question Refer a Patient 1.877.CALL NJH ( 877.225.5654 ) ... > Health Information > Healthy Lifestyle > Nutrition > Shortness of Breath and Eating Shortness of Breath ...

211

Clinical applications of breath testing  

PubMed Central

Breath testing has the potential to benefit the medical field as a cost-effective, non-invasive diagnostic tool for diseases of the lung and beyond. With growing evidence of clinical worth, standardization of methods, and new sensor and detection technologies the stage is set for breath testing to gain considerable attention and wider application in upcoming years.

Paschke, Kelly M; Mashir, Alquam

2010-01-01

212

Compressed breathing air - the potential for evil from within.  

PubMed

Human underwater activities rely on an adequate supply of breathable compressed gas, usually air, free from contaminants that could cause incapacitation underwater or post-dive or longer-term health effects. Potentially fatal but well-known hazards are hypoxia secondary to steel cylinder corrosion and carbon monoxide (CO) poisoning due to contaminated intake air. Another phenomenon may be behind some previously unexplained episodes of underwater incapacitation and perhaps death: low-level CO poisoning and/or the effects of gaseous contaminants generated within the compressor, including toluene and other volatile compounds. Many low molecular weight volatile contaminants are anaesthetic and will be potentiated by pressure and nitrogen narcosis. In sub-anaesthetic doses, impaired judgement, lowered seizure threshold and sensitisation of the heart to arrhythmias may occur. Toxic compounds can be volatilised from some compressor oils, especially mineral oils, in overheated compressors, or be created de novo under certain combinations of temperature, humidity and pressure, perhaps catalysed by metal traces from compressor wear and tear. Most volatiles can be removed by activated carbon filtration but many filters are undersized and may overload in hot, moist conditions and with short dwell times. A compressor that passes normal testing could contaminate one or more cylinders after heating up and then return to producing clean air as the filters dry and the systems cool. The scope of this problem is very unclear as air quality is tested infrequently and often inadequately, even after fatalities. More research is needed as well as better education regarding the safe operation and limitations of high-pressure breathing air compressors. PMID:22692708

Millar, Ian L; Mouldey, Peter G

2008-06-01

213

Combustion apparatus  

US Patent & Trademark Office Database

A combustion apparatus 2 has a fuel spraying nozzle 12, a feed canal 16 and a return canal 17, both the canals connected to the nozzle, with the former canal 16 feeding a fuel to the nozzle and with the latter canal 17 allowing an unsprayed portion of the fuel to flow back. An electromagnetic pump 18 disposed in the feed canal 16 serves to compress the fuel towards the nozzle 12, and an injector valve 25 is disposed in the return canal 17. A controller 40 regulates the operation of the injector valve 25 in the manner of duty-ratio control so as to adjust the flow rate of the fuel being sprayed out of the nozzle 12.

2005-06-21

214

Hydrogenation apparatus  

DOEpatents

Hydrogenation reaction apparatus comprising a housing having walls which define a reaction zone and conduits for introducing streams of hydrogen and oxygen into the reaction zone, the oxygen being introduced into a central portion of the hydrogen stream to maintain a boundary layer of hydrogen along the walls of the reaction zone. A portion of the hydrogen and all of the oxygen react to produce a heated gas stream having a temperature within the range of from 1100.degree. to 1900.degree. C., while the boundary layer of hydrogen maintains the wall temperature at a substantially lower temperature. The heated gas stream is introduced into a hydrogenation reaction zone and provides the source of heat and hydrogen for a hydrogenation reaction. There also is provided means for quenching the products of the hydrogenation reaction. The present invention is particularly suitable for the hydrogenation of low-value solid carbonaceous materials to provide high yields of more valuable liquid and gaseous products.

Friedman, Joseph (Encino, CA); Oberg, Carl L. (Canoga Park, CA); Russell, Larry H. (Agoura, CA)

1981-01-01

215

MEASURING APPARATUS  

DOEpatents

An ion chamber assembly is presented for measuring neutron emission of a relatively slow rate from a radioactive sample. The detecting apparatus comprises a container filled with neutron slowing material and having a cavity where a neutron source may be located centrally in the container. A plurality of ion chamber units are disposed equidistantly from the source and from each other for detecting the neutron radiation. Each of the ion chamber units has an ion chamber and a second chamber of substantially the same diameter as the ion chamber and in end-to-end relationship therewith. The second chamber contains paraffin and an axially disposed lead-in conductor for the ion chamber central electrode. The preamplifier circuit whose input is connected to the lead-in conductor is housed in a third container arranged in end-to-end relationship with the second chamber.

Kohman, T.P.; Weissbourd, B.W.

1959-02-17

216

Cryopump apparatus  

SciTech Connect

Cryopump apparatus includes means for supplying cryogenic fluid, means for supplying higher temperature refrigerant fluid, a panel having heat exchange surfaces on respective opposite sides thereof, with a conduit conducting cryogenic fluid therethrough, and a zigzag passageway formed by opposite sides of two radiation shields in spaced relationship with each other having the panel therebetween. The radiation shields are spaced from the panel, opcitally enclosing the panel therewithin. Corresponding edges of adjacent shields define open botton channel-configured passageways for flow of gas therethrough to respective heat exchange surfaces of a panel interjacent the shields. The shields include conduits for flow or refrigerant fluid therethrough. Heat insulative positioning spacer means contact with adjacent panels and a shield therebetween, maintaining the panels and shield in spaced relationship.

Bonn, J.W.

1984-09-11

217

Heliostat apparatus  

SciTech Connect

Heliostat apparatus for concentrating solar energy is described comprising a support structure disposed in a first plane and supporting a plurality of mirror units having freedom of substantial universal articulation thereon, each of the plurality of mirror units carrying at an upper portion thereof reflective element trained to receive incident rays of the sun and to focus reflection thereof to a desired focal point, adjustment structure operatively connected to the plurality of mirror units and disposed in a plane generally parallel to the first plane in which the support structure is disposed, the adjustment structure being shiftable to additional planes adjacent and generally parallel thereto to effect conjoint articulation of each of the mirror units at the support structure and thereby conjointly retrain the reflective element of each of the mirror units to receive incident rays of the sun and maintain reflection thereof on the focal point over the course of any day.

Bunch, J.C.

1980-08-19

218

Collecting apparatus  

DOEpatents

An improved collecting apparatus for small aquatic or airborne organisms such as plankton, larval fish, insects, etc. The improvement constitutes an apertured removal container within which is retained a collecting bag, and which is secured at the apex of a conical collecting net. Such collectors are towed behind a vessel or vehicle with the open end of the conical net facing forward for trapping the aquatic or airborne organisms within the collecting bag, while allowing the water or air to pass through the apertures in the container. The container is readily removable from the collecting net whereby the collecting bag can be quickly removed and replaced for further sample collection. The collecting bag is provided with means for preventing the bag from being pulled into the container by the water or air flowing therethrough.

Duncan, Charles P. (Walnut Creek, CA)

1983-01-01

219

Gameboard apparatus  

US Patent & Trademark Office Database

A gameboard apparatus picturing an advanced, economic, technological civilization throughout the solar system and beyond, a path of spaceships containing many contingency circumstances interspersed between man-made, unpurchaseable property containing many contingency circumstance, and eleven major types of purchaseable man-made properties containing many contingency circumstances. The indicia on color-coded leases describes the internal, external, vertical and horizontal development of real estate in over thirty ways, four decks of cards, Speed of Light Years Utility Service Card and Speed of Light Years Ticket Tokens color coded to work in conjunction with the path of spaceships which are path of the continuous open route with a starting point from Earth, the entire game being described by a set of rules.

1990-08-07

220

Cooking apparatus  

US Patent & Trademark Office Database

A cooking apparatus comprises a trough, a well, and a pot. The trough is configured to hold a first cooking medium. The trough has insulated floors, insulated walls, and a steam pipe as a heating element to directly heat the first cooking medium. The well is joined to a cover plate. The cover plate is configured to fit over the trough with a seal, such that at least a portion of the well extends into the trough for submersion into the first cooking medium. The pot is inserted in the well. A second cooking medium may be introduced in the well adjacent to the pot. A food product such as goetta may be introduced to the pot for cooking. Heat may be transferred from the heating element, to the first cooking medium, to the well, to the second cooking medium, to the pot, and then to the goetta.

Glier; Daniel William (Covington, KY)

2010-06-01

221

46 CFR 115.650 - Alternative Hull Examination (AHE) Program options: Divers or underwater ROV.  

Code of Federal Regulations, 2010 CFR

...Program options: Divers or underwater ROV. 115.650 Section 115.650 Shipping...Program options: Divers or underwater ROV. To complete your underwater survey...an underwater remotely operated vehicle (ROV). (a) If you use divers to...

2010-10-01

222

46 CFR 115.650 - Alternative Hull Examination (AHE) Program options: Divers or underwater ROV.  

Code of Federal Regulations, 2010 CFR

...Program options: Divers or underwater ROV. 115.650 Section 115.650 Shipping...Program options: Divers or underwater ROV. To complete your underwater survey...an underwater remotely operated vehicle (ROV). (a) If you use divers to...

2009-10-01

223

Breathing patterns during varied activities.  

PubMed

The level of ventilation attained and breathing patterns adopted during activity have important implications for the distribution and deposition of particles that are inhaled. However, breathing patterns and levels of ventilation adopted during specific physical activities are unknown. We used a noninvasive means of measuring ventilation in subjects performing a variety of activities (bicycling, arm ergometry, lifting, and pulling) during unencumbered (no mouthpiece) breathing and while breathing through a mouthpiece. Minute ventilation (VE), tidal volume (VT), inspiratory time (TI), and total breathing cycle time (TT) were measured initially both spirometrically and from body surface displacements. When a mouthpiece was used, VE and breathing patterns were significantly altered during all activities such that VE, VT, and TT increased by 16, 34, and 20%, respectively. This mouthpiece effect was attenuated at the higher levels of VE. A task dependency of breathing pattern was also noted such that there was much greater variability of VT and TI for a given VE during the lifting activity compared with bicycling (coefficient of variation for VT of 0.39 +/- 0.09 vs. 0.20 +/- 0.07, P less than 0.01; and for TI of 0.38 +/- 0.08 vs. 0.21 +/- 0.08, P less than 0.01). We conclude that a mouthpiece significantly alters breathing pattern during varied types and intensities of activities, and breathing patterns may differ significantly from one activity to another. When the total dose of particulates inhaled in the lung are assessed, the mouthpiece effect and activity effect on breathing pattern must be considered. PMID:1400052

Paek, D; McCool, F D

1992-09-01

224

Thermal status of wet-suited divers using closed circuit O2 apparatus in sea water of 17-18.5 degrees C.  

PubMed

A wet suit may not provide adequate thermal protection when diving in moderately cold water (17-18 degrees C), and any resultant mild hypothermia may impair performance during prolonged diving. We studied heat exchange during a dive to a depth of 5 m in sea water (17-18.5 degrees C) in divers wearing a full wet suit and using closed-circuit oxygen breathing apparatus. Eight fin swimmers dived for 3.1 h and six underwater scooter (UWS) divers propelled themselves through the water for 3.7 h. The measurements taken throughout the dive were the oxygen pressure in the cylinder and skin and rectal temperatures (Tre). Each subject also completed a cold score questionnaire. The Tre decreased continuously in all subjects. Oxygen consumption in the fin divers (1.40 l.min-1) was higher than that of the UWS divers (1.05 l.min-1). The mean total insulation was 0.087 degree C.m2.W-1 in both groups. Mean body insulation was 37% of the total insulation (suit insulation was 63%). The reduction in Tre over the 1st hour was related to subcutaneous fat thickness. There was a correlation between cold score and Tre at the end of 1 h, but not after that. A full wet suit does not appear to provide adequate thermal protection when diving in moderately cold water. PMID:9243172

Arieli, R; Kerem, D; Gonen, A; Goldenberg, I; Shoshani, O; Daskalovic, Y I; Shupak, A

1997-01-01

225

Simulated high altitude diving experiment for the underwater construction operation.  

PubMed

The simulated dive experiments were conducted at the high altitude of 4500 meters and 5000 meters, for the requirement of diving operation in the lakes at the altitude of 4442 meters for the construction of large-scale hydroelectric power station. The high & low pressure chamber-complex was used, and 15 professional divers participated in the experiment. The divers were stayed at the altitude of 4500 and 5000 meters for 7-9 days. Totally 85 persons-times of dives to the depths of 30-50 meters were operated; they stayed under the water for 30-90 minutes while processing physical activities. During the experiment, we studied the pressurization procedure, decompression table, and physiological functions of the divers. The results indicate that, although the relative pressure differences between the surface and underwater was larger at high altitude than at sea level, the appropriate prolongation of the compression time was able to prevent the difficulty in pressure regulation for the divers to avoid the injury of middle ear. Four tables of the decompression A, B, C and D was calculated with Haldane's theory, and the speed of decompression increased in the order from A to D. The safest procedure was C, and there was no decompression sickness and bubbles in body of the divers. The methods of decompression included underwater stage decompression, surface decompression, oxygen-breathing decompression, and repetitive diving decompression. The surface decompression was the most suitable method for the high altitude, as it could greatly decrease the time in the cold water for the divers. The power spectrum analysis of EEG (electroencephalogram) indicated that, when the divers were exposed to the altitude of 5000 meters, the delta activity in EEG increased, alpha and beta activity decreased. And the delta activity decreased, the alpha and beta activity increased while diving during a dry condition. According to the diving and decompression procedure studied under simulated conditions, 272 person-times of diving training and underwater operations were processed in a high altitude hydroelectric power station at the altitude of 4442 meters, including photographing, video-recording, measuring, and drilling. There were no signs and symptoms of decompression sickness and bubbles. PMID:14519911

Zhong-Yuan, Shi; Xi-Wei, Tang; Yan-Meng, Zhang

2003-09-01

226

Underwater Stereoscopic Television and Display Realism.  

National Technical Information Service (NTIS)

Conventional closed-circuit underwater television systems lack display realism, making remote manipulation and positioning difficult. Stereoscopic and head-coupled television systems were developed to provide three-dimensional position and orientation inf...

R. B. Fugitt R. W. Uhrich

1973-01-01

227

Underwater Launched Missile System Canister Design.  

National Technical Information Service (NTIS)

This document expands on the canister requirements for an Under-water Launched Missile System (ULMS) as proposed in volume 6 of the 1967 STRAT-X Committee Report. Functional flow, environmental requirements and interfaces are identified. Preliminary desig...

W. H. Hine E. F. Wallace

1969-01-01

228

Underwater Work Performance and Work Tolerance.  

National Technical Information Service (NTIS)

Work conducted at the University of California, Los Angeles in the area of underwater work performance and work tolerance during 1972 has concentrated on two principal areas: the development of a family of curves describing the effects of pertinent enviro...

G. H. Egstrom G. Weltman M. A. Willis W. J. Cuccaro

1973-01-01

229

Piezoelectric materials used in underwater acoustic transducers  

SciTech Connect

Piezoelectric materials have been used in underwater acoustic transducers for nearly a century. In this paper, we reviewed four different types of piezoelectric materials: piezoelectric ceramics, single crystals, composites, and polymers, which are widely used in underwater acoustic transducers nowadays. Piezoelectric ceramics are the most dominant material type and are used as a single-phase material or one of the end members in composites. Piezoelectric single crystals offer outstanding electromechanical response but are limited by their manufacturing cost. Piezoelectric polymers provide excellent acoustic impedance matching and transducer fabrication flexibility although their piezoelectric properties are not as good as ceramics and single crystals. Composites combined the merits of ceramics and polymers and are receiving increased attention. The typical structure and electromechanical properties of each type of materials are introduced and discussed with respect to underwater acoustic transducer applications. Their advantages and disadvantages are summarized. Some of the critical design considerations when developing underwater acoustic transducers with these materials are also touched upon.

Li, Huidong; Deng, Zhiqun; Carlson, Thomas J.

2012-07-07

230

Sensor network architectures for monitoring underwater pipelines.  

PubMed

This paper develops and compares different sensor network architecture designs that can be used for monitoring underwater pipeline infrastructures. These architectures are underwater wired sensor networks, underwater acoustic wireless sensor networks, RF (radio frequency) wireless sensor networks, integrated wired/acoustic wireless sensor networks, and integrated wired/RF wireless sensor networks. The paper also discusses the reliability challenges and enhancement approaches for these network architectures. The reliability evaluation, characteristics, advantages, and disadvantages among these architectures are discussed and compared. Three reliability factors are used for the discussion and comparison: the network connectivity, the continuity of power supply for the network, and the physical network security. In addition, the paper also develops and evaluates a hierarchical sensor network framework for underwater pipeline monitoring. PMID:22346669

Mohamed, Nader; Jawhar, Imad; Al-Jaroodi, Jameela; Zhang, Liren

2011-11-15

231

Study of Underwater Sound Ray Tracing Methodology  

National Technical Information Service (NTIS)

An operational study has been made of algorithms employed in short base line underwater position location systems. Some important sources of systematic error have been uncovered. The issues studied include isospeed vs. isogradient ray tracing, effect of t...

R. R. Read

1990-01-01

232

Nature of Metallurgical Reactions in Underwater Welding.  

National Technical Information Service (NTIS)

The pyrometallurgical reactions are characterized as a function of depth for underwater wet welding. The influence of weld metal compositional variations with depth on weld metal microstructure are described. Metallurgical suggestions as to compositional ...

S. Ibarra D. L. Olson C. E. Grubbs

1987-01-01

233

Underwater Technology Conference -84. Deep Water Technology.  

National Technical Information Service (NTIS)

The conference proceedings contain 29 papers reflecting the challenges to industry and research in developing the oil and gas reserves on the Norwegian continental shelf. The following topics are covered: Underwater production systems; Field development p...

J. A. Andersen

1984-01-01

234

Underwater Observation Increases Understanding of Marine Mammals.  

National Technical Information Service (NTIS)

Manned undersea techniques have recently allowed direct visual observation of the underwater behavior and environments of marine mammals. This paper mentions several examples of observations by other workers and reviews three cases in which the writer has...

G. C. Ray

1974-01-01

235

Remote Repair Grinding of Cracks Underwater.  

National Technical Information Service (NTIS)

This paper presents a new approach for remote grinding of cracks underwater. The approach uses Controlled Material Removal Rate (CMRR) grinding strategy, which is based on a force controlled manipulator for handling the grinding machine. The CMRR-strategy...

T. Thomessen T. K. Lien K. Johnsen

1994-01-01

236

Underwater Work Performance and Work Tolerance.  

National Technical Information Service (NTIS)

The report presents findings of the research efforts for 1971 in the study of underwater work performance and work tolerance conducted at the University of California, Los Angeles. The studies were directed towards the development of performance decrement...

G. H. Egstrom G. Weltman A. D. Baddeley W. J. Cuccaro M. A. Willis

1972-01-01

237

Underwater Viewing System Using Sound Holography.  

National Technical Information Service (NTIS)

A feasibility study and prototype system development for an underwater viewing system based on acoustic holographic principles was initiated. The objective was to study various receiving array configurations and construct a modular prototype system to eva...

P. N. Keating R. Koppelmann R. F. Steinberg

1972-01-01

238

Underwater Explosion Bubble Jetting Effects on Infrastructure.  

National Technical Information Service (NTIS)

Underwater explosions present a significant risk to structures because they were not designed for these types of loads and because water transmits explosive energy much more efficiently than air. The US Navy demonstrated that the effect of bubble jetting ...

G. Chahine G. Harris J. Fortune J. L. O'Daniel R. Ilamni

2011-01-01

239

Building Underwater Remotely Operated Vehicles (ROVs)  

NSDL National Science Digital Library

Educators with an interest in hands-on science, technology, engineering and mathematics (STEM) disciplines will receive introductory instructions on how to design, engineer and build a fully functional underwater ROV.

Woodall, Debra

240

Medical diagnostics by laser-based analysis of exhaled breath  

NASA Astrophysics Data System (ADS)

IMany trace gases can be found in the exhaled breath, some of them giving the possibility of a non invasive diagnosis of related diseases or allowing the monitoring of the disease in the course of its therapy. In the present lecture the principle of medical diagnosis based on the breath analysis will be introduced and the detection of trace gases in exhaled breath by high- resolution molecular spectroscopy in the IR spectral region will be discussed. A number of substrates and the optical systems for their laser detection will be reported. The following laser based experimental systems has been realised in the Molecular Spectroscopy Laboratory in ENEA in Frascati for the analysis of specific substances in the exhaled breath. A tuneable diode laser absorption spectroscopy (TDLAS) appartus for the measurement of 13C/12C isotopic ratio in carbon dioxide, a TDLAS apparatus for the detection of CH4 and a CO2 laser based photoacoustic system to detect trace ethylene at atmospheric pressure. The experimental set-up for each one of the a.m. optical systems will be shown and the related medical applications will be illustrated. The concluding remarks will be focuses on chemical species that are of major interest for medical people today and their diagnostic ability.

Giubileo, Gianfranco

2002-08-01

241

Career Opportunities Outdoors and Underwater  

NSDL National Science Digital Library

The ATETV project delivers web-based videos to connect students to careers in advanced technology. In this episode of ATETV, marine technology and environmental technology are discussed. A student competition of remotely operated underwater vehicle technology is shown in the video. Employees with training and experience in this technology are in high demand in the workforce, and industry is using such competitions as scouting opportunities. In technological programs like the ones shown here, students gain hands-on experience that prepares them for the workplace. The episode can be watched in full or through the two segments: âDiving into A Marine-Based Career,â and âEnvironmental Technology Takes to the Great Outdoors.â Running time for the full episode of this streaming video is 7:01.

2010-07-27

242

High bandwidth underwater optical communication.  

PubMed

We report error-free underwater optical transmission measurements at 1 Gbit/s (10(9) bits/s) over a 2 m path in a laboratory water pipe with up to 36 dB of extinction. The source at 532 nm was derived from a 1064 nm continuous-wave laser diode that was intensity modulated, amplified, and frequency doubled in periodically poled lithium niobate. Measurements were made over a range of extinction by the addition of a Mg(OH)(2) and Al(OH)(3) suspension to the water path, and we were not able to observe any evidence of temporal pulse broadening. Results of Monte Carlo simulations over ocean water paths of several tens of meters indicate that optical communication data rates >1 Gbit/s can be supported and are compatible with high-capacity data transfer applications that require no physical contact. PMID:18188210

Hanson, Frank; Radic, Stojan

2008-01-10

243

Stabilization and coordination of underwater gliders  

Microsoft Academic Search

An underwater glider is a buoyancy-driven, fixed-wing underwater vehicle that redistributes internal mass to control attitude. We examine the dynamics of a glider restricted to the vertical plane and derive a feedback law that stabilizes steady glide paths. The control law is physically motivated and with the appropriate choice of output can be interpreted as providing input-output feedback linearization. With

Pradeep Bhatta; Naomi Ehrich Leonard

2002-01-01

244

Affordable underwater wireless optical communication using LEDs  

NASA Astrophysics Data System (ADS)

In recent years the need for high data rate underwater wireless communication (WC) has increased. Nowadays, the conventional technology for underwater communication is acoustic. However, the maximum data rate that acoustic technology can provide is a few kilobits per second. On the other hand, emerging applications such as underwater imaging, networks of sensors and swarms of underwater vehicles require much faster data rates. As a result, underwater optical WC, which can provide much higher data rates, has been proposed as an alternative means of communication. In addition to high data rates, affordable communication systems become an important feature in the development requirements. The outcome of these requirements is a new system design based on off-the-shelf components such as blue and green light emitting diodes (LEDs). This is due to the fact that LEDs offer solutions characterized by low cost, high efficiency, reliability and compactness. However, there are some challenges to be met when incorporating LEDs as part of the optical transmitter, such as low modulation rates and non linearity. In this paper, we review the main challenges facing the incorporation of LEDs as an integral part of underwater WC systems and propose some techniques to mitigate the LED limitations in order to achieve high data rate communication

Pilipenko, Vladimir; Arnon, Shlomi

2013-09-01

245

An underwater optical wireless communication network  

NASA Astrophysics Data System (ADS)

The growing need for underwater observation and sub-sea monitoring systems has stimulated considerable interest in advancing the enabling technologies of underwater wireless communication and underwater sensor networks. This communication technology is expected to play an important role in investigating climate change, in monitoring biological, bio-geochemical, evolutionary and ecological changes in the sea, ocean and lake environments and in helping to control and maintain oil production facilities and harbors using unmanned underwater vehicles (UUVs), submarines, ships, buoys, and divers. However, the present technology of underwater acoustic communication cannot provide the high data rate required to investigate and monitor these environments and facilities. Optical wireless communication has been proposed as the best alternative to meet this challenge. We present models of three kinds of optical wireless communication links a) a line-of-sight link, b) a modulating retro-reflector link and c) a reflective link, all of which can provide the required data rate. We analyze the link performance based on these models. From the analysis, it is clear that as the water absorption increases, the communication performance decreases dramatically for the three link types. However, by using the scattered lighted it was possible to mitigate this decrease in some cases. We conclude from the analysis that a high data rate underwater optical wireless network is a feasible solution for emerging applications such as UUV to UUV links and networks of sensors, and extended ranges in these applications could be achieved by applying a multi-hop concept.

Arnon, Shlomi

2009-08-01

246

Electronic analysis of foetal breathing movements: a practical application of phase-lock-loop principles.  

PubMed

Measurement of foetal breathing movements is becoming more common as a means of monitoring processes occurring in the human foetus. Conventional time-period analysis of breathing movements is prone to error owing to their complexity, and it is laborious to decipher any frequency pattern. The described apparatus has been designed to give an on-line visual indication of the instantaneous frequency of foetal breathing movements when measured by a time-distance recorder connected to an echoscope. It is affected insignificantly by spurious signals, and can be build cheaply with easily-available components. Practical trials suggest that frequency analysis by this device can be of value for examining episodes of continuous breathing movements in the foetus. PMID:712803

Stagg, J; Gennser, G

1978-09-01

247

Social relations and breath odour.  

PubMed

In this retrospective qualitative study, the researcher reviewed 55 client records of The Breath Odour Clinic. The purpose was to determine if individuals attended a clinic specialised in treating oral malodour for medical or social reasons. The study focused on the psychosocial and breath odour history. Clients had agreed to the use of information for research purposes. Society uses odour as a means to define and interact with the world. The olfactory, smelling experience is intimate, emotionally charged and connects us with the world. It follows that the smell from mouth breath odour can connect or disconnect a person from their social environment and intimate relationships. How one experiences one's own body is very personal and private but also very public. Breath odour is public as it occurs within a social and cultural context and personal as it affects one's body image and self-confidence. Body image, self-image and social relations mesh, interact and impact upon each other. Breath odour is a dynamic and interactive aspect of the self-image. In addition, breath odour may be value-coded as 'bad'. In 75% of the cases reviewed, decreased self-confidence and insecurity in social and intimate relations led clients to seek treatment at the specialised breath odour clinic. Their doctor, dental hygienist or dentist had treated medical and oral conditions but not resolved their breath odour problem. When a person perceives a constant bad breath problem, she/he uses defence techniques, and may avoid social situations and social relations. This affects a person's well-being. PMID:16451502

McKeown, L

2003-11-01

248

Optimization of Configuration of Autonomous Underwater Vehicle for Inspection of Underwater Cables  

Microsoft Academic Search

Deals with the configuration of autonomous underwater vehicle (AUV) for inspection of underwater cables considering low hydrodynamic drag, sensor alignment, collision avoidance manoeuvre, turning manoeuvre and rolling motion. The AUV consists of a fuselage of body of revolution with low hydrodynamic drag, fore and aft horizontal wings, upper and lower vertical tails and a pair of horizontal thrusters at both

Naomi Kato; Junichi Kojima; Yoichi Kato; Sigetake Matumoto; Kenichi Asakawa

1998-01-01

249

Hydrogenation apparatus  

DOEpatents

Hydrogenation reaction apparatus is described comprising a housing having walls which define a reaction zone and conduits for introducing streams of hydrogen and oxygen into the reaction zone, the oxygen being introduced into a central portion of the hydrogen stream to maintain a boundary layer of hydrogen along the walls of the reaction zone. A portion of the hydrogen and all of the oxygen react to produce a heated gas stream having a temperature within the range of from 1,100 to 1,900 C, while the boundary layer of hydrogen maintains the wall temperature at a substantially lower temperature. The heated gas stream is introduced into a hydrogenation reaction zone and provides the source of heat and hydrogen for a hydrogenation reaction. There also is provided means for quenching the products of the hydrogenation reaction. The present invention is particularly suitable for the hydrogenation of low-value solid carbonaceous materials to provide high yields of more valuable liquid and gaseous products. 2 figs.

Friedman, J.; Oberg, C.L.; Russell, L.H.

1981-06-23

250

Attachment Apparatus  

DOEpatents

The present invention includes an attachment apparatus comprising a rotation limiting member adapted to be threaded onto a threaded member; and a preload nut adapted to be threaded onto the threaded member. The rotation limiting member comprises a plurality of pins; and the preload nut comprises plurality of slots, preferably wherein the plurality of pins and the plurality of slots are the same in number, which is preferably three. The plurality of pins of the rotation limiting member are filled into a corresponding plurality of slots of the preload nut to form a rotatable unit adapted to be threaded onto the threaded member. In use, the rotatable unit is threaded onto the threaded member. The present invention thus provides a unitized removable device for holes, including holes other than circular in shape, which have an established depth before an end of, or before an enlargement of the hole. The configuration of some exposed part of the device, or the head, is shaped and formed for its intended purpose, such as clamping, anchor points, eye bolts, stud anchor, and the like. The device allows for the installation, preloading and removal of all components of the device, as a unit, without damage to the member for which attachment is required by simple rotations of some exposed part of the device.

Morrison, Edward F.

1998-08-18

251

Reducing the dilution of breath samples for breath hydrogen testing.  

PubMed

Breath hydrogen testing has a diagnostic potential as a gastrointestinal function test that could be performed in general practice. The purpose of this study was to improve techniques for collection of breath samples and transfer of samples to transport vessels. Breath samples from 10 dogs were collected using both a snug-fitting and a loose-fitting standard anesthetic mask attached to a reservoir bag, and a modified snug-fitting system. CO(2) was used as internal standard and mean CO(2) concentrations were 1.19+/-0.76, 2.17+/-0.66 and 2.68+/-0.92, respectively. Additional samples were saved in transport tubes for 19 days, during which the hydrogen and carbon dioxide concentrations remained stable. A reliable method for transferring the breath samples from the reservoir bag to vacuum transport tubes was also identified. Our results demonstrate less contamination of breath samples with air than previously reported, and a reproducible method to transfer breath samples to transport vessels. PMID:19095274

Toresson, L; Steiner, J M; Williams, D A

2008-12-17

252

Birmingham assessment of breathing study (BABS)  

Microsoft Academic Search

Background:Current international resuscitation guidelines for lay people rely on the assessment of normal breathing as a key sign of breathing and circulation. However, it is not known how accurately laypersons can discriminate between normal and abnormal breathing. The aim of this study was to test the ability of medical students to discriminate between simulated normal and abnormal breathing patterns and

Gavin D. Perkins; Barney Stephenson; Jonathan Hulme; Koenraad G. Monsieurs

2005-01-01

253

EDITORIAL: Bad breath and exhaled breath analysis---common fields with common denominators Bad breath and exhaled breath analysis---common fields with common denominators  

Microsoft Academic Search

During the 20th century, bad breath and analysis of breath for medical diagnosis evolved as two separate fields. Papers on bad breath were published almost exclusively in dental journals, whereas papers on exhaled breath analysis were more commonly found in medical and chemical analysis journals. When Daniel van Steenberghe and Mel Rosenberg first discussed setting up an international society for

Mel Rosenberg; Anton Amann

2008-01-01

254

Visualizing Breath using Digital Holography  

NASA Astrophysics Data System (ADS)

Artist Jayne Wilton and physicists Peter Hobson and Ivan Reid of Brunel University are collaborating at Brunel University on a project which aims to use a range of techniques to make visible the normally invisible dynamics of the breath and the verbal and non-verbal communication it facilitates. The breath is a source of a wide range of chemical, auditory and physical exchanges with the direct environment. Digital Holography is being investigated to enable a visually stimulating articulation of the physical trajectory of the breath as it leaves the mouth. Initial findings of this research are presented. Real time digital hologram replay allows the audience to move through holographs of breath-born particles.

Hobson, P. R.; Reid, I. D.; Wilton, J. B.

2013-02-01

255

Stuffing box and grease injector for underwater wells  

SciTech Connect

This paper discusses an hydraulically actuated underwater stuffing box having a through passageway for flexible line. Also described is an underwater grease injector section having a through passageway for flexible line.

Gentry, E.B.; Boyle, C.S.

1990-08-28

256

Testing a Force Sensor for Underwater Magnetic Particle Inspection.  

National Technical Information Service (NTIS)

Offshore oil and gas production installations require regular inspection of their underwater structures. Magnetic particle inspection (MPI) is one of the most reliable methods of detecting cracks in these parts. The use of underwater manipulators for remo...

J. Vaelttilae

1991-01-01

257

Performance Limits of Fair-Access in Underwater Sensor Networks.  

National Technical Information Service (NTIS)

This paper investigates fundamental performance limits of medium access control (MAC) protocols for particular underwater multi-hop sensor networks under a fair-access criterion requiring that sensors have an equal rate of underwater frame delivery to a b...

D. Du G. G. Xie J. Gibson M. Peng Y. Xiao

2009-01-01

258

Identification of underwater vehicle dynamics with neural networks  

Microsoft Academic Search

In this paper modeling of underwater vehicle dynamics using neural networks is investigated. Extensive knowledge is available on the behaviour of underwater vehicles. However, it may prove disadvantageous to use an off line established model of the dynamics due to the varying nature of the underwater environment. Neural networks offer interesting possibilities as they can be used to update the

Pepijn van de Ven; C. Flanagan; D. Toal

2004-01-01

259

SDRT: A reliable data transport protocol for underwater sensor networks  

Microsoft Academic Search

In this paper, we investigate the reliable data transport problem in underwater sensor networks. Underwater sensor networks are significantly different from terrestrial sensor networks in two aspects: acoustic channels are used for communication and most sensor nodes are mobile due to water current. These distinctions feature underwater sensor networks with low available bandwidth, large propagation delay, highly dynamic topology, and

Peng Xie; Zhong Zhou; Zheng Peng; Jun-Hong Cui; Zhijie Shi

2010-01-01

260

Scalable Localization with Mobility Prediction for Underwater Sensor Networks  

Microsoft Academic Search

Due to harsh aqueous environments, non-negligible node mobility and large network scale, localization for large-scale mobile underwater sensor networks is very challenging. In this paper, by utilizing the predictable mobility patterns of underwater objects, we propose a scheme, called Scalable Localization scheme with Mobility Prediction (SLMP), for underwater sensor networks. In SLMP, localization is performed in a hierarchical way, and

Robert Zhong Zhou; James Zheng Peng; Jun-Hong Cui; Zhijie Shi; Amvrossios C. Bagtzoglou

2011-01-01

261

Data Collection with Multiple Mobile Actors in Underwater Sensor Networks  

Microsoft Academic Search

Underwater sensor networks (USNs) could provide real time in-situ monitoring to supply high spatio-temporal resolution capability. However underwater environment represents many challenges for sensor networks. It has become an urgent problem to get high temporal precision sampling data from USNs and to prolong USNspsila lifetime at the same time. In this paper, we present an underwater application model for collecting

Jincheng Wang; Deshi Li; Mi Zhou; Dipak Ghosal

2008-01-01

262

AUV-Aided Localization for Underwater Sensor Networks  

Microsoft Academic Search

We propose a localization scheme for underwater acoustic sensor networks (UWSN) that does not require a priori infra-structure or synchronization between nodes. An autonomous underwater vehicle (AUV) aids in localizing the sensor nodes while roaming across the underwater sensor field. The objectives of this paper are to describe how to localize nodes using AUV and to describe the tradeoffs involved,

Melike Erol; L. F. M. Vieira; M. Gerla

2007-01-01

263

Multipath Virtual Sink Architecture for Underwater Sensor Networks  

Microsoft Academic Search

The salient features of acoustic communications render many schemes that have been designed for terrestrial sensor networks unusable underwater. We therefore propose a novel virtual sink architecture for underwater sensor networks that aims to achieve robustness and energy efficiency under harsh underwater channel conditions. To overcome the long propagation delay and adverse link conditions in such environments, we make use

Winston K. G. Seah; Hwee-Xian Tan

2006-01-01

264

Efficient Data Delivery with Packet Cloning for Underwater Sensor Networks  

Microsoft Academic Search

Underwater sensor networks (UWSNs) promises new opportunities for exploration of the oceans which cover more than 70% of the earth's surface. Researchers envision the deployment of dense networks of untethered sensors underwater for data acquisition to better understand the underwater environment, while military and security forces see the great potential of using this technology for mine reconnaissance, intrusion detection and

Peng Sun; W. K. G. Seah; P. W. Q. Lee

2007-01-01

265

AUV-Aided Localization for Underwater Sensor Networks  

Microsoft Academic Search

We propose a localization scheme for underwater acoustic sensor networks (UWSN) that does not require a priori infrastructure or synchronization between nodes. An Autonomous Underwater Vehicle (AUV) aids in localizing the sensor nodes while roaming across the underwater sensor field. The objectives of this paper are to describe how to localize nodes using AUV and to describe the trade-offs involved,

Melike Erol; Luiz Filipe M. Vieira; Mario Gerla

2009-01-01

266

Scalable Localization with Mobility Prediction for Underwater Sensor Networks  

Microsoft Academic Search

Due to adverse aqueous environments, non-negligible node mobility and large network scale, localization for large-scale mobile underwater sensor networks is very challenging. In this paper, by utilizing the predictable mobility patterns of underwater objects, we propose a scheme, called Scalable Localization scheme with Mobility Prediction (SLMP), for underwater sensor networks. In SLMP, localization is performed in a hierarchical way, and

Zhong Zhou; Jun-hong Cui; Amvrossios Bagtzoglou

2008-01-01

267

Nonholonomic motion control of an autonomous underwater vehicle  

Microsoft Academic Search

A submersible can carry limited supply of fuel onboard. Use of control planes along with propeller for major part of its motion can conserve much energy; thus extending the duration of underwater missions. Such an underwater vehicle has nonholomic nature due to its nonlinear kinematic structure. The authors describe the kinematics of an underwater vehicle by six state variables and

Yoshihiko Nakamura; Shrikant Savant

1991-01-01

268

A vision-based system for autonomous underwater vehicle navigation  

Microsoft Academic Search

This paper describes the work for the design and development of an autonomous underwater vehicle (AUV). The reference missions are sea bottom surveys and sealines inspections. A vision-based system for the automatic underwater vehicle is presented. The detection of underwater pipeline borders and its symmetry axis is performed. The method adopted for edge detection consists of two steps: 1) a

Gian Luca Foresti; Stefania Gentili; Massimo Zampato

1998-01-01

269

Spectrum-Aware Underwater Networks: Cognitive Acoustic Communications  

Microsoft Academic Search

Communication capacity in underwater acoustic networks is severely limited by the uniquely challenging characteristics of underwater acoustic communications (UACs). In this article, dynamic spectrum sharing inspired from cognitive radio (CR) is applied to UAC networks, and spectrum-aware underwater networks (SUNs), i.e., cognitive acoustic communications (CACs), are proposed. First, the problem of spectrum scarcity in SUN is elaborately discussed by investigating

A. Bicen; A. Sahin; Ozgur Akan

2012-01-01

270

An Underwater Augmented Reality system for commercial diving operations  

Microsoft Academic Search

This paper describes the implementation of a novel prototypical underwater augmented reality (UWAR) system that provides visual aids to increase commercial divers' capability to detect, perceive, and understand elements in underwater environments. During underwater operations, a great amount of stress is imposed on divers by environmental and working conditions such as pressure, visibility, weightlessness, current, etc. Those factors cause a

R. Morales; P. Keitler; P. Maier; G. Klinker

2009-01-01

271

Overview of channel models for underwater wireless communication networks  

Microsoft Academic Search

Acoustic communication in Underwater Wireless Communication Networks (UWCNs) has several challenges due to the presence of fading, multipath and refractive properties of the sound channel which necessitate the development of precise underwater channel models. Some existing channel models are simplified and do not consider multipath or multipath fading. In this paper, a detailed survey on ray-theory-based multipath Rayleigh underwater channel

Mari Carmen Domingo

2008-01-01

272

Using optical communication for remote underwater robot operation  

Microsoft Academic Search

Underwater vehicles are typically operated using a tether or a slow acoustic link. We present an underwater optical communication system that enables a high-throughput and low-latency link to an underwater robot. The optical link allows the robot to operate in cluttered environments without the need for a tether. We demonstrate the performance of the system in a number of experiments

Marek Doniec; Carrick Detweiler; Iuliu Vasilescu; Daniela Rus

2010-01-01

273

Underwater acoustics and the Royal Navy, 18931930  

Microsoft Academic Search

The real impetus for the research in underwater acoustics was the German U-boat menace of World War I. Traditional naval methods were of little use against the submarine, and thus British scientists concentrated on underwater detection. This led to the development of the hydrophone (an underwater microphone), which was extensively used during the war. As this instrument had many drawbacks,

W. D. Hackmann

1979-01-01

274

Long endurance underwater power system  

NASA Astrophysics Data System (ADS)

As part of DARPA's Artificial Gill program, Aquanautics is developing an underwater power source that uses an ambient pressure solid polymer electrolyte (SPE) hydrogen/oxygen fuel cell with an artificial gill that extracts dissolved oxygen from seawater and an Alwatt aluminum corrosion cell that generates the hydrogen. The innovation in this concept is a direct carrier feed fuel cell (CFFC) process which allows the fuel cell to operate at ambient pressure without a costly deep water pressure vessel. Activities during this quarter include: direct feed of oxygen carrier into fuel cell; new batches of electrodes were ordered. These are with a different ion-exchange membrane called Nafion (manufactured by Dupont) as against Raipore (mfd. by RAI Research). There was some concern that hydrogen at high pressures would leak out through the membrane which led to calculation of the hydrogen leakage; it appears that at 6000 m, the loss will be around 20 percent. Eight rectangular membrane cartridges were ordered. The factors varied were type of membrane (solid vs. microporous) and fiber to fiber distance. Theoretical study for sizing of the gill and pumping power required was carried out. Integration of the gill and fuel cell was carried out where oxygen extracted from synthetic ocean water was used in the fuel cell. There was no unforeseen problem. Hydrogen generation using an Alwatt battery was obtained and tested.

1989-08-01

275

An Ultrasonic Sensor Based Low-Power Acoustic Modem for Underwater Communication in Underwater Wireless Sensor Networks  

Microsoft Academic Search

Applications of underwater sensor networks involve environmental monitoring, disaster prevention, and resource detection.\\u000a As the importance of these applications has recently grown, underwater sensor networks made up of sensor nodes have to be\\u000a further investigated. However, little research has been performed to develop an underwater sensor node with communication\\u000a functionality. In an underwater environment, typical RF-based communication is not appropriate

Heungwoo Nam; An Sunshin

2007-01-01

276

Simplified model of underwater electrical discharge.  

PubMed

A model of the underwater discharge with initiating wire is presented. The model reveals the nature of similarity parameters which have been phenomenologically introduced in earlier experimental research in order to predict behavior of different discharges. It is shown that these parameters naturally appear as a result of the normalization of differential equations, which determines the process of underwater wire initiated discharge. In these equations the energy conservation law for wire material evaporation and the dependence of plasma conductivity on the energy dissipated in the discharge are implied to calculate the time varying resistance of the discharge gap. The comparison of calculations with the experimental results shows that good agreement is achieved when modification of these parameters is introduced. These new similarity parameters are functions of the original similarity parameters, hence the law of the similarity of underwater electrical discharge is preserved. PMID:15089410

Gurovich, V Ts; Grinenko, A; Krasik, Ya E; Felsteiner, J

2004-03-11

277

Magnetic gradiometer for underwater detection applications  

NASA Astrophysics Data System (ADS)

We have designed and constructed a magnetic gradiometer for underwater mine detection, location and tracking. The United States Naval Surface Warfare Center (NSWC PC) in Panama City, FL has conducted sea tests of the system using an unmanned underwater vehicle (UUV). The Real-Time Tracking Gradiometer (RTG) measures the magnetic field gradients caused by the presence of a mine in the Earth's magnetic field. These magnetic gradients can then be used to detect and locate a target with the UUV in motion. Such a platform can also be used for other applications, including the detection and tracking of vessels and divers for homeland (e.g., port) security and the detection of underwater pipelines. Data acquired by the RTG in sea tests is presented in this paper.

Kumar, S.; Skvoretz, D. C.; Moeller, C. R.; Ebbert, M. J.; Perry, A. R.; Ostrom, R. K.; Tzouris, A.; Bennett, S. L.; Czipott, P. V.; Sulzberger, G.; Allen, G. I.; Bono, J.; Clem, T. R.

2006-06-01

278

Multi-frame underwater image restoration  

NASA Astrophysics Data System (ADS)

Ability to image underwater is highly desired for scientific and military applications, including optical communications, submarine awareness, diver visibility, and mine detection. Underwater imaging is severely impaired by scattering and optical turbulence associated with refraction index fluctuations. This work introduces novel approach to restoration of degraded underwater imagery based on multi-frame correction technique developed for atmospheric distortions. The method represents synthesis of "lucky-region" fusion and optical flow based image warping. Developed multi-frame image restoration algorithm is applied to sets of images collected in laboratory under controlled conditions as well as field test data. Reliance of image restoration on sophistication of the optical flow algorithm is shown. Variable degrees of image degradation mitigation which manifest themselves as high spatial frequency content recovery are demonstrated depending on imaging conditions and ratio of typical image spatial frequency scale to typical degradation spatial frequency scale.

Kanaev, A. V.; Hou, W.; Woods, S.

2011-10-01

279

To breathe free  

SciTech Connect

This book was organized by the Center's East European program and supported primarily by a grant from the Rockefeller Brothers' Fund. This book reports on the new political forces that swept Communist regimes from power throughout the region in 1989 and are now struggling to set up post-Communist governments and institutions. Nor need they do so. This volume does not attempt to be a current account of the state of environmental policy and official institutions in Eastern Europe. New institutions are only slowly taking shape. In the meantime, much of the old apparatus remains in place. The new leaders and parties have found it difficult to cover the economic cost or accept the political risk of imposing expensive environmental controls on the large industrial enterprises that are the principal polluters. In Poland and Hungary we see the real threat of a political backlash from workers facing unemployment when such enterprises lose even part of their state budget subsidy, let alone face new charges for pollution control or penalties for its absence. The separate environmental movement that played a prominent part in the overthrow of Communist power has not, moreover, survived as a powerful separate political party anywhere in Eastern Europe. Its chances appeared greatest in East Germany and Czechoslovakia but in neither place has the Green political organization expanded or even maintained its pre-1989 leverage.

DeBardeleben, J.

1991-01-01

280

The optical monitor system of anti-phobic raid underwater  

NASA Astrophysics Data System (ADS)

The underwater security system, used in the Qingdao sailboat game of 2008 Olympic Games, combined multiple underwater cameras with sonar detectors, forms an underwater barrier, which can observe the movement of suspicious objects and get the underwater video images continuously and instantly. The lighting system can provide sufficient illumination matched with target to reach the best imaging result. The whole system with the function of centralized control, depth measurement, leakage alarm and image processing, is the original equipment in domestic underwater antiterrorism optical research area.

Zheng, Chengdong; Weng, Yan-Sheng; Liu, Xi-Zhan

2009-07-01

281

Underwater noise from offshore oil production vessels.  

PubMed

Underwater acoustic recordings of six Floating Production Storage and Offloading (FPSO) vessels moored off Western Australia are presented. Monopole source spectra were computed for use in environmental impact assessments of underwater noise. Given that operations on the FPSOs varied over the period of recording, and were sometimes unknown, the authors present a statistical approach to noise level estimation. No significant or consistent aspect dependence was found for the six FPSOs. Noise levels did not scale with FPSO size or power. The 5th, 50th (median), and 95th percentile source levels (broadband, 20 to 2500 Hz) were 188, 181, and 173 dB re 1 ?Pa @ 1 m, respectively. PMID:23742441

Erbe, Christine; McCauley, Robert; McPherson, Craig; Gavrilov, Alexander

2013-06-01

282

Network for Underwater Archaeology, Ireland (NUA)  

NSDL National Science Digital Library

Hosted by the University of Ulster, this site provides information and networking opportunities in the field of underwater archaeology in Ireland. Included here are photographs and descriptions of recent and ongoing excavations of shipwrecks, submerged forests, and other interesting underwater archaeological sites. The information is presented with academic expertise but still provides fascinating reading for the casual visitor. The site also hosts a bulletin board, news about the upcoming conference at the University -- Towards An Understanding Of Maritime Archaeology In Ireland -- and annotated links to two dozen related Websites.

283

Isotropic light source for underwater applications  

NASA Astrophysics Data System (ADS)

The design and construction of an isotropic light source is described. The instrument's design is well suited to underwater applications. Any combination of light sources (flashlamps, CW sources, or lasers) and spectral filters (absorption or interference) can be simultaneously incorporated to provide a single isotropic source with any desired temporal and spectral characteristics. This design was recently used in an underwater experiment that required a synchronously triggered isotropic flash to simultaneously measure absorption, scattering, and attenuation. The design of this particular isotropic source is presented along with data demonstrating the isotropy of the light field produced by the source.

Brown, Robert A.; Honey, Richard C.; Maffione, Robert A.

1991-12-01

284

Riser position indication apparatus  

Microsoft Academic Search

This patent describes a Riser Position Indication Apparatus for disposition between an offshore vessel and a riser, the riser being moveable with respect to the offshore vessel. The riser position indication apparatus comprises: vessel connection means operatively engaged with the vessel to secure the riser position indication apparatus to the vessel, riser connection means operatively engaged with the riser to

1986-01-01

285

Apparatus for detecting leaks  

DOEpatents

A method and apparatus for determining the position of and estimating the size of leaks in an evacuating apparatus comprising the use of a testing gas such as helium or hydrogen flowing around said apparatus whereby the testing gas will be drawn in at the site of any leaks.

Booth, Eugene T. (New York, NY)

1976-02-24

286

Do pressure-demand breathing systems safeguard against inward leakage  

SciTech Connect

A slight positive pressure in the facepiece throughout the breathing cycle is used in presure-demand, compressed-air breathing apparatus to eliminate any inward leakage. In the present work an inward leakage test with SF/SUB/6 was used to measure facepiece penetration in a pressure-demand system at different work loads. Inspiratory-flow pressure variations within the facepiece and heat rate were also measured. Tests were performed on a dummy head and on 2 subjects. In some tests a poor face seal was introduced. It was found that inward leakage was less than 0.0001% under all conditions as long as facepiece pressure was positive. When facepiece pressure fell below zero, at inhalation peak flows about 300 l/min, an inward leakage was detected. The results show that pressure-demand systems should be tested with a breathing machine giving peak flows of at least 300 l/min to ascertain the capability of these systems to maintain positive pressure in the facepiece during hard rescue work.

Dahlbaeck, G.O.; Novak, L.

1983-05-01

287

Do pressure-demand breathing systems safeguard against inward leakage?  

PubMed

Rescue operations conducted in toxic atmospheres require respiratory protective equipment capable of providing a very high degree of protection. A slight positive pressure in the facepiece throughout the breathing cycle is used in the pressure-demand, compressed-air breathing apparatus to eliminate any inward leakage. In the present work an inward leakage test with sulphur hexafluoride (SF6) was used to measure facepiece penetration in a pressure-demand system at different work loads. During the test, inspiratory-flow pressure variations within the facepiece and heart rate were also measured. Tests were performed on a dummy head and on two subjects. In some tests a poor face seal was introduced by putting an open tubing with an inner diameter of 2 mm and outer diameter of 3 mm under the sealing edge of the mask. It was found that inward leakage was less than 0.0001% under all conditions as long as facepiece pressure was positive. When facepiece pressure fell below zero, which occurred at inhalation peak flows about 300 L/min, an inward leakage was detected. One subject achieved, at extreme work load, an inhalation peak flow around 450 L/min. These results show that pressure-demand systems should be tested with a breathing machine giving peak flows of at least 300 L/min to ascertain the capability of these systems to maintain positive pressure in the facepiece during hard rescue work. PMID:6869251

Dahlbck, G O; Novak, L

1983-05-01

288

Breathing and temporomandibular joint disease.  

PubMed

Temporomandibular joint disease (TMD) refers to a collection of pain related conditions in the masticatory muscles and temporomandibular joint. Occlusal factors have been implicated in TMD pathogenesis, yet despite decades of research no causal relationship between occlusion and TMD has been found. The significance of psychosocial factors in both the assessment and the long-term management of patients with TMD is receiving increased recognition. The teaching of relaxation skills and coping strategies are effective, proven TMD therapies. The role of breathing re-education in temporomandibular joint (TMJ) disorders is rarely mentioned. A focus on breathing patterns and their disorders potentially explains how biomechanical factors associated with psychosocial influences might lead to pathophysiological changes within the TMJ as well as in the associated muscles. Attention to factors such as breathing and postural rehabilitation provides health professionals valuable, additional tools to help care for patients with TMD. PMID:21665104

Bartley, Jim

2010-06-25

289

Imposed Work of Breathing and Breathing Comfort of Nonintubated Volunteers Breathing with Three Portable Ventilators and a Critical Care Ventilator.  

National Technical Information Service (NTIS)

In spontaneous breathing modes, past laboratory work using a lung model indicated portable ventilators as compared to critical care ventilators may increase inspiratory work of breathing. The purpose of this study was to assess the imposed inspiratory wor...

P. N. Austin

2001-01-01

290

Underwater Archaeology in Egypt and the Protection of its Underwater Cultural Heritage  

NASA Astrophysics Data System (ADS)

After many years of individual attempts to explore the underwater cultural heritage (UCH) of Egypt, the Supreme Council for Antiquities (SCA) established a department specializing in the field during the last decade of the twentieth century. The collaboration between this department and foreign missions led to the discoveries of a number of underwater sites and projects focusing on their protection, including mitigation work. This article presents the most important discoveries and displays the efforts of the SCA in the management of the UCH.

Abd-el-Maguid, Mohamed M.

2012-10-01

291

Operation of bad breath clinics.  

PubMed

The diagnosis and management of bad breath can be easily incorporated in routine dental care by attending dentists. This article outlines the information necessary to establish a differential diagnosis of oral malodor. This includes evaluation of medical, dental, and halitosis history. It also includes the examination of extraoral and intraoral tissues and a thorough periodontal examination. The presence of bad breath is established with organoleptic and hydrogen sulfide-monitor (Halimeter) measurements. The treatment of malodor resulting from oral overgrowth of anaerobic organisms in the oral cavity consists of mechanical and chemical reduction of the microbial flora by methods that are supported by scientific evidence. PMID:10635282

Neiders, M; Ramos, B

1999-05-01

292

Contention free MAC protocol based on priority in underwater acoustic communication  

Microsoft Academic Search

Underwater acoustic sensor network technology can be applied in underwater environment such as the sea or rivers. It can be mainly used for data acquisition, underwater exploration, prevention of natural disasters, unattended environmental monitoring systems, and military for underwater surveillance. Despite of this promising outlook, underwater sensor network has so many limitations in communicating, due to a harsh environment like

Hui-Jin Cho; Jung-Il Namgung; Nam-Yeol Yun; Soo-Hyun Park; Chang-Hwa Kim; Young-Sun Ryuh

2011-01-01

293

A solar-powered autonomous underwater vehicle  

Microsoft Academic Search

To meet the rapidly expanding requirements for Autonomous Underwater Vehicles (AUVs), Falmouth Scientific, Inc. (FSI) is working in cooperation with the Autonomous Undersea Systems Institute (AUSI) and Technology Systems Inc. (TSI) to develop a vehicle capable of long-term deployment and station-keeping duties. It has long been considered that AUV platforms, in principle, could provide an effective solution for surveillance (security

J. Jalbert; J. Baker; J. Duchesney; P. Pietryka; W. Dalton; D. R. Blidberg; S. Chappell; R. Nitzel; K. Holappa

2003-01-01

294

Underwater Video Mosaics as Visual Navigation Maps  

Microsoft Academic Search

This paper presents a set of algorithms for the creation of underwa- ter mosaics and illustrates their use as visual maps for underwater vehicle navigation. First, we describe the automatic creation of video mosaics, which deals with the problem of image motion estimation in a robust and automatic way. The motion estimation is based on a initial matching of corresponding

Nuno R. Gracias; Jos Santos-victor

2000-01-01

295

Experiments with Underwater Robot Localization and Tracking  

Microsoft Academic Search

This paper describes a novel experiment in which two very different methods of underwater robot localization are compared. The first method is based on a geometric approach in which a mobile node moves within a field of static nodes, and all nodes are capable of estimating the range to their neighbours acoustically. The second method uses visual odometry, from stereo

Peter I. Corke; Carrick Detweiler; Matthew Dunbabin; Michael Hamilton; Daniela Rus; Iuliu Vasilescu

2007-01-01

296

Muzzle Brake for an Underwater Gun.  

National Technical Information Service (NTIS)

A device for use as a muzzle brake for an underwater gun having a projectile conveying structure with concentric inner and outer cylinders. The inner cylinder has at least one longitudinal slot formed therein. A sealing means joins the projectile conveyin...

I. N. Kirschner G. R. Berlam

1997-01-01

297

Broadband FIR Beamformer for Underwater Aoustic Communication  

Microsoft Academic Search

Beamforming for underwater acoustic communication (UAC) is affected by the broadband feature of UAC signal, which has relatively low center frequency compared with the signal bandwidth. The narrow-band assumption does not hold good in the UAC. (Unrealistic assumption) In this paper, we present computer simulation results of a broadband FIR beamformer for UAC using the baseband equivalent array signal model

Youngchol Choi; Yong-kon Lim

2006-01-01

298

KE Basin underwater visual fuel survey  

SciTech Connect

Results of an underwater video fuel survey in KE Basin using a high resolution camera system are presented. Quantitative and qualitative information on fuel degradation are given, and estimates of the total fraction of ruptured fuel elements are provided. Representative photographic illustrations showing the range of fuel conditions observed in the survey are included.

Pitner, A.L.

1995-02-01

299

Enabling autonomous capabilities in underwater robotics  

Microsoft Academic Search

Underwater operations present unique challenges and opportunities for robotic applications. These can be at- tributed in part to limited sensing capabilities, and to lo- comotion behaviours requiring control schemes adapted to specific tasks or changes in the environment. From enhancing teleoperation procedures, to providing high-level instruction, all the way to fully autonomous operations, enabling autonomous capabilities is fundamental for the

Junaed Sattar; Gregory Dudek; Olivia Chiu; Ioannis M. Rekleitis; Philippe Gigure; Alec Mills; Nicolas Plamondon; Chris Prahacs; Yogesh Girdhar; Meyer Nahon; John-paul Lobos

2008-01-01

300

Standard small targets for calibrating underwater sonars  

Microsoft Academic Search

Ping-pong balls form convenient reference targets for underwater sonars. Theoretical and experimental studies have confirmed that the acoustic target strength of such a ball can be predicted to within about +\\/-.58 dB over a wide range of frequencies, even down to frequencies at which the wavelength in water exceeds the radius of the ball. Computed and experimental results are compared.

V. G. Welsby; J. E. Hudson

1972-01-01

301

Damping of Underwater Explosion Bubble Oscillations  

Microsoft Academic Search

When an explosive detonates underwater it creates a bubble of gas which performs damped radial oscillations of large amplitude. The usual theory of these oscillations treats the water as incompressible and yields undamped oscillations of constant period. We have modified this theory by taking account of the compressibility of the water. Our theory predicts damped oscillations of diminishing period. Comparison

Joseph B. Keller; Ignace I. Kolodner

1956-01-01

302

Optimal and Adaptive Control of Underwater Vehicles  

Microsoft Academic Search

This article contains a continuous-time optimal and adaptive control scheme for underwater vehicles moving in six degrees of freedom. The control scheme is an extension of the algorithm of [4] and a modification of the algorithm found in [6]. The algorithm is optimal in the sense that it minimizes the state errors and the forces which contribute to the vehicle's

Svein I. Sagatun

1993-01-01

303

Robust observer design for underwater vehicles  

Microsoft Academic Search

In this paper we propose a new observer system for underwater vehicles. The main design objective behind this strategy is to reduce the effect of the destabilizing Coriolis and centripetal forces and moments. For low cost vehicles with limited measurement equipment, these forces and moments represent a significant challenge for automatic control when the forward speed is high. However, by

Jon E. Refsnes; A. J. Sorensen; Kristin Y. Pettersen

2006-01-01

304

Adaptive region control for autonomous underwater vehicles  

Microsoft Academic Search

In this paper, we propose a new control concept called adaptive region control, for autonomous underwater vehicle (AUV). In this new control concept, the desired objective can be specified as a region instead of a point. The proposed control law does not require any knowledge of the inertia matrix, Coriolis and centripetal force, hydrodynamic damping, and parameters of the gravity

C. C. Cheah; Y. C. Sun

2004-01-01

305

Aided inertial navigation systems for underwater vehicles  

Microsoft Academic Search

This paper addresses the design and performance of precision autonomous navigation systems for underwater vehicles. The use of inertial navigation systems aided by velocity sensors and periodic position fixes is examined. Equipment such as the ship's log, the doppler sonar, the correlation velocity log, and position fixes using such systems as acoustic and magnetic benchmarks, and radio systems such as

Dan Johnson; Steve Eppig

1987-01-01

306

Pressure-Balanced Gas Turbine Underwater Launcher.  

National Technical Information Service (NTIS)

An underwater launcher of a vehicle in a launching tube outside the pressure hull of a submerged launch platform is unaffected by launch depth. A muzzle cap at one end of the tube communicates with ambient water and a ram plate at the other end communicat...

B. B. Macleod P. E. Moody

2001-01-01

307

Camera Jig for Underwater Stereoscopic Photography.  

National Technical Information Service (NTIS)

A portable camera jig for use by divers in making close-up, stereoscopic photographs of underwater surfaces with a single lens camera includes in combination with a sheet metal frame, a clear water box for operation in turbid water and that will permit il...

J. Millteman C. O. Warrell R. S. Peterson

1979-01-01

308

Spatial diversity processing for underwater acoustic telemetry  

Microsoft Academic Search

A large increase in the reliability of shipboard or stationary underwater acoustic telemetry systems is achievable by using spatially distributed receivers with aperture sizes from 0.35 to 20 m. Output from each receiver is assigned a quality measure based on the estimated error rate, and the data, weighted by the quality measure, are combined and decoded. The quality measure is

Josko A. Catipovic; L. E. Freitag

1991-01-01

309

Adaptive Data Delivery for Underwater Sensor Networks  

Microsoft Academic Search

With the rapid development of terrestrial wireless sensor network technology, and considering that more than 70% of the Earth's surface is covered by water, the increasing research focus on Underwater Wireless Sensor Networks (UWSNs) is not unexpected. Acoustic communications, which is the current viable transmission technique adopted by UWSNs, has a signal propagation delay that is five orders of magnitude

Peng Sun; W. K. Seah

2007-01-01

310

Barrier coverage for underwater sensor networks  

Microsoft Academic Search

Using sonar to detect submarines was an effective method. Current technologies, however, have made it possible for submarines to thwart standard (active or passive) sonar mechanisms [1]. Thus, finding alternatives to detect submarines becomes important and timely. One viable alternative is to use magnetic or acoustic sensors in close proximity of possible underwater pathways a submarine may pass through. This

Stanley Barr; Benyuan Liu; Jie Wang

2008-01-01

311

3D Underwater Sensor Network Localization  

Microsoft Academic Search

We transform the 3D underwater sensor network (USN) localization problem into its 2D counterpart by employing sensor depth information and a simple projection technique. We first prove that a nondegenerative projection preserves network localizability. We then prove that given a network and a constant k, all of the geometric k-lateration localization methods are equivalent. Based on these results, we design

Amin Y. Teymorian; Wei Cheng; Liran Ma; Xiuzhen Cheng; Xicheng Lu; Zexin Lu

2009-01-01

312

Reconfigurable acoustic modem for underwater sensor networks  

Microsoft Academic Search

There is a growing interest for underwater sensor networks where long term monitoring of water masses around the world for scientific, environmental, commercial, and military reasons is desired. In this paper we will present the concept of a highly flexible acoustic modem called the Reconfigurable Modem (rModem) that can be used for rapid testing and development of such networks.

Ethem Mutlu Szer; Milica Stojanovic

2006-01-01

313

Autonomous depth adjustment for underwater sensor networks  

Microsoft Academic Search

To fully understand the ocean environment requires sensing the full water column. Utilizing a depth adjustment system on an underwater sensor network provides this while also improving global sensing and communications. This paper presents a depth adjustment system for waters of up to 50m deep that connects to the AquaNode sensor network. We performed experiments characterizing the system and demonstrating

Carrick Detweiler; Marek Doniec; Iuliu Vasilescu; Elizabeth Basha; Daniela Rus

2010-01-01

314

AquaNodes: an underwater sensor network  

Microsoft Academic Search

This paper describes an underwater sensor network with dual communication and support for sensing and mobil- ity. The nodes in the system are connected acoustically for broadcast communication using an acoustic modem we de- veloped. For higher point to point communication speed the nodes are networked optically using custom built opti- cal modems. We describe the hardware details of the

Iuliu Vasilescu; Carrick Detweiler; Daniela Rus

2007-01-01

315

Last Progress in Underwater Electrical Wire Explosion  

Microsoft Academic Search

The results of the investigation of the underwater electrical wire explosions using a high power nanosecond timescale generator are reported. The spectroscopic analysis of the emitted radiation has unveiled no evidence for the formation of shunting plasma channel. The latter appears in vacuum and gas wire explosions and causes to the seizure of energy deposition into an exploding wire material.

Alon Grinenko; Arkady Sayapin; Sergey Efimov; Alexander Fedotov; Yakov E. Krasik

2008-01-01

316

Hydrodynamic implications for submarine launched underwater gliders  

Microsoft Academic Search

Underwater gliders are a type of long range unmanned vehicle that use bouyancy control and lifting surfaces to travel in a sawtooth trajectory through the water column. These vehicles are typically employed by oceanographers for environmental monitoring and also show promise as a sensor platform in military applications. This paper presents investigations of vehicle hydrodynamics relating to the deployment of

Joshua D. Rodgers; John M. Wharington

2010-01-01

317

Underwater path planing using fast marching algorithms  

Microsoft Academic Search

In this paper, new tools for obstacle avoidance and path planning for underwater vehicles are presented. The authors' technique, based on a level set formulation of the path planning problem, extracts optimal paths from complex and continuous environments in a complete and consistent manner. Fast marching algorithm is known to be efficient for finding cost optimal path in mobile robotics

Clment Ptrs; Yan Pailhast; Yvan Petilloti; Dave Lanes

2005-01-01

318

Robot motion estimation improves underwater sonar accuracy  

Microsoft Academic Search

Underwater sonar system is currently the best solution to distinguish a hazardous target from the harmless objects or a flock of fish at a far distance in the water, subsequently protect the harbors' security. A good sonar system should have the ability to survey a long range, in the meantime reserve a high accuracy. Noise is a crucial problem affecting

Lian Yu; N. Neretti; N. Intrator

2005-01-01

319

Underwater remote-reading dosimeter evaluation  

Microsoft Academic Search

This paper reports on problems inherent in attempting to measure underwater dose rates and monitor and control diver exposures. At Connecticut Yankee, the authors had a specific procedure in effect to cover diving evolutions; however, the authors were not satisfied with the methods available to us for monitoring a diver's dose during a dive. The authors looked around and discovered

H. E. Clow; G. Emmons

1985-01-01

320

Underwater Noise from Skiffs to Ships  

Microsoft Academic Search

How loud are the underwater sounds emitted by skiffs, work boats, tour vessels, and cruise ships? The answer to this question is an important element of any effort to assess potential impacts of vessel operations on marine life. It is also important from a vessel management standpoint as managers attempt to understand whether oversight of individual vessels, vessel types, and

Blair Kipple; Chris Gabriele

321

Autonomous buoyancy-driven underwater gliders  

Microsoft Academic Search

A class of small (50 kg, 2 m length), reusable autonomous underwater vehicles capable of operating at speeds of 20-30 cm\\/s with ranges several thousand kilometers and durations of months has been developed and tested. The vehicles, essentially autonomous profiling floats with wings, execute sawtooth patterns between the surface, where they are located and communicate to shore, and depths of

Russ E. Davis; Charles C. Eriksen; Clayton P. Jones

2002-01-01

322

Acoustic signals of underwater explosions near surfaces  

Microsoft Academic Search

Underwater explosions are conventionally identified and characterized by their seismic and\\/or acoustic signature based on spherical models of explosion bubbles. These models can be misleading in cases where the bubble is distorted by proximity to the free surface, the bottom, or to a solid object. An experimental and numerical study of the effects of various nearby surfaces on the bubble's

John R. Krieger; Georges L. Chahine

2005-01-01

323

Underwater communication past, present and future  

Microsoft Academic Search

Part A of this paper is a brief report on the contributions made by various workers with experience in the field of underwater communications, which includes both data telemetry and speech, at an informal meeting held on the 11 th and 12th April 1967 at the Department of Electronic and Electrical Engineering of the University of Birmingham. The main aim

H. O. Berktay; B. K. Gazey; C. A. Teer

1968-01-01

324

Underwater sonic ray tracing in three dimensions  

Microsoft Academic Search

A description is given of a simple and flexible computing procedure for the application of Snell's law to sonic ray tracing in three dimensions. An easy method of step-by-step ray tracing, in which ray direction cosines are used, is presented and an illustration of underwater ray paths is given. Now at the Meteorological Office, Bracknell, Berkshire, England.

P. A. Einstein

1975-01-01

325

Classification of ships using underwater radiated noise  

Microsoft Academic Search

Concentrating mainly on the signal processing and physical models behind the algorithms used to classify ships by their underwater-radiated noise, the physical model for cavitation is expanded to include the losses by acoustical radiation and the heat transfer from the vapor to the fluid. The resulting equation allows one to find the characteristics of cavitation through simulation. Five algorithms for

J. G. Lourens

1988-01-01

326

Heterogeneous system framework for underwater networking  

Microsoft Academic Search

The integration of Radio Frequency (RF) Command and Control (C2) networks with underwater (UW) networks that are based on acoustic communications requires comprehensive solutions to address several technical challenges and interoperability issues. A major constraint arises from the large capability gap between acoustic and RF communications, the former being characterized by very low data rates and a propagation speed over

Alessandro Berni; Diego Merani; John Potter; Robert Been

2011-01-01

327

Biosensor for underwater chemical sensing (Invited Paper)  

Microsoft Academic Search

Emerging biosensor approaches may prove useful in reducing false positives and improving detection probabilities for unexploded ordnance (UXO) and underwater explosives. NRL researchers previously developed a biosensor that was field-tested and validated for use in environmental remediation to detect explosives in groundwater. The sensor relies on the selective recognition by antibodies of target analytes, including the common explosives TNT and

Anne W. Kusterbeck; Jeffrey R. Deschamps; Paul T. Charles

2005-01-01

328

An eigenpath underwater acoustic communication channel simulation  

Microsoft Academic Search

One of the less reliable communication channels is the underwater acoustic channel. This is due to its reverberant properties produced by the surface and the bottom of the sea and Doppler spreading caused by the transmitter and the receiver movements. To foresee some characteristics it is important to develop a reliable model. An accurate model allows to evaluate the channel

M. A. Munoz Gutierrez; P. L. Prospero Sanchez; J. V. do Vale Neto

2005-01-01

329

Channel modeling for underwater optical communication  

Microsoft Academic Search

We consider in this paper channel modeling for underwater optical channels. In particular, we focus on the channel impulse response and quantify the channel time dispersion under different conditions of water type, link distance, and transmitter\\/receiver parameters. We use the Monte Carlo approach to simulate the trajectories of emitted photons propagating in water towards the receiver. We show that in

Chadi Gabriel; Mohammad-Ali Khalighi; Salah Bourennane; Pierre Leon; Vincent Rigaud

2011-01-01

330

An integrated, underwater optical \\/acoustic communications system  

Microsoft Academic Search

Communication underwater is severely limited when compared to communications in air because water is essentially opaque to electromagnetic radiation except in the visible band. Even in the visible band, light penetrates only a few hundred meters in the clearest waters and much less in waters made turbid by suspended sediment or high concentrations of marine life. Consequently, acoustic techniques have

N. Farr; A. Bowen; J. Ware; C. Pontbriand; M. Tivey

2010-01-01

331

Modular hardware infrastructure for autonomous underwater vehicles  

Microsoft Academic Search

Autonomous underwater vehicles (AUVs) are taking on increasingly visible and valuable roles in oceanographic research institutions, the offshore industry, and the military (Podder et al., 2004 and Yongkuan, 2002). AUV research, especially at the university level, is hindered by the lack of flexible and affordable platforms suitable for a wide range of applications. This paper presents an electrical and mechanical

Ian Wang; Bradley Factor; Sam Fladung; Ryan Stenson

2005-01-01

332

Trajectory Control Strategies for the Underwater Glider  

Microsoft Academic Search

The linear quadratic regulator for the underwater glider is designed, and the motion path of the feedback control system in ocean vertical plane is studied. First, changes of the trajectory path when the glider is in steady moving are tested in this paper. Then, according to the fact that the glider needs sharp turning, two kinds of control strategies are

Yanhui Wang; Hongwei Zhang; Shuxin Wang

2009-01-01

333

TECHNOLOGY NEEDS FOR AUTONOMOUS UNDERWATER VEHICLES  

Microsoft Academic Search

This paper considers the technology needs for autonomous underwater vehicles as the middle layer of a three-layer process. The first layer is the high level User Requirement, which may be stated in the form of business objectives such as 'competitive running cost' or 'less than 1 hour per week downtime'. These business objectives map on to the middle layer of

Gwyn Griffiths

334

Practice makes perfect, even for breathing  

PubMed Central

Breathing relies on a respiratory rhythm generator. A study characterizes an early emerging oscillatory group of Phox2b-expressing parafacial cells that entrain and couple with the preBtzinger Complex at the onset of fetal breathing.

Feldman, Jack L; Kam, Kaiwen; Janczewski, Wiktor A

2010-01-01

335

Managing Stress with Tancheon Breathing Meditation  

Microsoft Academic Search

The purpose of this paper is to introduce the concept of Tancheon Breathing Meditation as a self-healing form of managing stress as illustrated in the ?Tancheon Breathing Meditation Self-Healing Wheel Model? described later in this essay. In this essay, I hope to convey the important role of the ?tancheon? (lower abdomen) and on how breathing through the tancheon combined with

Gracia Del Rosario

336

Breath Ammonia Analysis: Clinical Application and Measurement  

Microsoft Academic Search

This review covers in detail the complexity of human breath, how the body metabolizes ammonia, clinical conditions which are directly related to the regulation of ammonia concentration, and analysis of current techniques that are capable of detecting breath ammonia. Focusing on these areas provides the information needed to develop a breath ammonia sensor for monitoring dysfunction of the human body.

Troy Hibbard; Anthony J. Killard

2011-01-01

337

Speech Breathing in Children and Adolescents.  

ERIC Educational Resources Information Center

A study of 80 children, aged 7, 10, 13, and 16, found that gender was not an important variable in speech breathing, but age was. The youngest group exhibited such things as larger lung, rib cage, and abdominal volume initiations and terminations for breath groups and fewer syllables per breath group. (Author/JDD)

Hoit, Jeannette D.; And Others

1990-01-01

338

Breathing resistance of dust respirators  

Microsoft Academic Search

In several of the operations, at Olin Corporation, the use of dust respirators is left to the discretion of the worker since the total solid particulate levels are considerably below the OSHA permissible exposure level. A problem arises when the worker who would use the respirators except: 1) it's hard to breathe through them, 2) the respirators fog our safety

1985-01-01

339

Apparatus for transporting hazardous materials  

DOEpatents

An apparatus and method are provided for selectively receiving, transporting, and releasing one or more radioactive samples for analysis on a differential thermal analysis (DTA) apparatus. The apparatus includes a portable sample transporting apparatus for storing and transporting the samples and includes a support assembly for supporting the transporting apparatus when a sample is transferred to the DTA apparatus. The transporting apparatus includes a storage member which includes a plurality of storage chambers arrayed circumferentially with respect to a central axis.

Osterman, R.A.; Cox, R.

1991-01-22

340

Portable containment sleever apparatus  

DOEpatents

A sleever apparatus includes an inner member with a central passage through which an item to be sleeved is passed. An outer member surrounds the inner member and defines a space between the members for holding a supply of containment material, which is preferably plastic sleeving. The apparatus has a handle which allows a user to hold the apparatus and walk the apparatus along the length of the item to be sleeved. As the user passes the item through the sleever apparatus, the containment material exits through a slit at one end of the apparatus in order to contain the item. The sleever apparatus may be formed of disposable materials, such as cardboard, and may be intended for a single use application. Alternatively, the sleever apparatus may be comprised of more permanent materials such as PVC or fiberglass. The sleever apparatus may include a serrated end for cutting the containment material and may include appropriate tubing and valves for either directing an inert gas into the containment material around the item or for withdrawing air from within the containment material in order to create a vacuum. In one embodiment, the sleever apparatus has a cartridge that can be replaced with another cartridge once the supply of the containment material has been depleted.

Rea, Michael J. (North Augusta, SC); Brown, Roger A. (North Augusta, SC)

2000-01-01

341

Neural mechanisms underlying breathing complexity.  

PubMed

Breathing is maintained and controlled by a network of automatic neurons in the brainstem that generate respiratory rhythm and receive regulatory inputs. Breathing complexity therefore arises from respiratory central pattern generators modulated by peripheral and supra-spinal inputs. Very little is known on the brainstem neural substrates underlying breathing complexity in humans. We used both experimental and theoretical approaches to decipher these mechanisms in healthy humans and patients with chronic obstructive pulmonary disease (COPD). COPD is the most frequent chronic lung disease in the general population mainly due to tobacco smoke. In patients, airflow obstruction associated with hyperinflation and respiratory muscles weakness are key factors contributing to load-capacity imbalance and hence increased respiratory drive. Unexpectedly, we found that the patients breathed with a higher level of complexity during inspiration and expiration than controls. Using functional magnetic resonance imaging (fMRI), we scanned the brain of the participants to analyze the activity of two small regions involved in respiratory rhythmogenesis, the rostral ventro-lateral (VL) medulla (pre-Btzinger complex) and the caudal VL pons (parafacial group). fMRI revealed in controls higher activity of the VL medulla suggesting active inspiration, while in patients higher activity of the VL pons suggesting active expiration. COPD patients reactivate the parafacial to sustain ventilation. These findings may be involved in the onset of respiratory failure when the neural network becomes overwhelmed by respiratory overload We show that central neural activity correlates with airflow complexity in healthy subjects and COPD patients, at rest and during inspiratory loading. We finally used a theoretical approach of respiratory rhythmogenesis that reproduces the kernel activity of neurons involved in the automatic breathing. The model reveals how a chaotic activity in neurons can contribute to chaos in airflow and reproduces key experimental fMRI findings. PMID:24098396

Hess, Agathe; Yu, Lianchun; Klein, Isabelle; De Mazancourt, Marine; Jebrak, Gilles; Mal, Herv; Brugire, Olivier; Fournier, Michel; Courbage, Maurice; Dauriat, Gaelle; Schouman-Clayes, Elisabeth; Clerici, Christine; Mangin, Laurence

2013-10-03

342

Neural Mechanisms Underlying Breathing Complexity  

PubMed Central

Breathing is maintained and controlled by a network of automatic neurons in the brainstem that generate respiratory rhythm and receive regulatory inputs. Breathing complexity therefore arises from respiratory central pattern generators modulated by peripheral and supra-spinal inputs. Very little is known on the brainstem neural substrates underlying breathing complexity in humans. We used both experimental and theoretical approaches to decipher these mechanisms in healthy humans and patients with chronic obstructive pulmonary disease (COPD). COPD is the most frequent chronic lung disease in the general population mainly due to tobacco smoke. In patients, airflow obstruction associated with hyperinflation and respiratory muscles weakness are key factors contributing to load-capacity imbalance and hence increased respiratory drive. Unexpectedly, we found that the patients breathed with a higher level of complexity during inspiration and expiration than controls. Using functional magnetic resonance imaging (fMRI), we scanned the brain of the participants to analyze the activity of two small regions involved in respiratory rhythmogenesis, the rostral ventro-lateral (VL) medulla (pre-Btzinger complex) and the caudal VL pons (parafacial group). fMRI revealed in controls higher activity of the VL medulla suggesting active inspiration, while in patients higher activity of the VL pons suggesting active expiration. COPD patients reactivate the parafacial to sustain ventilation. These findings may be involved in the onset of respiratory failure when the neural network becomes overwhelmed by respiratory overload We show that central neural activity correlates with airflow complexity in healthy subjects and COPD patients, at rest and during inspiratory loading. We finally used a theoretical approach of respiratory rhythmogenesis that reproduces the kernel activity of neurons involved in the automatic breathing. The model reveals how a chaotic activity in neurons can contribute to chaos in airflow and reproduces key experimental fMRI findings.

Hess, Agathe; Yu, Lianchun; Klein, Isabelle; De Mazancourt, Marine; Jebrak, Gilles; Mal, Herve; Brugiere, Olivier; Fournier, Michel; Courbage, Maurice; Dauriat, Gaelle; Schouman-Clayes, Elisabeth; Clerici, Christine; Mangin, Laurence

2013-01-01

343

Report of a Survey of US Academic Programs in Ocean and Underwater Acoustics.  

National Technical Information Service (NTIS)

Underwater acoustics remains the principal means to detect and locate submarines and other underwater objects. For this reason, the Office of Naval Research has sponsored a vigorous research program in underwater acoustics and related fields at both acade...

K. W. Lackle

1997-01-01

344

Underwater Noise and the Conservation of Divers' Hearing: A Review. Volume 1.  

National Technical Information Service (NTIS)

A critical review of past research conducted on underwater hearing, particularly on underwater thresholds of audibility, has revealed that current underwater noise exposure limits may be too lax. Further new experimental work at suprathreshold sound level...

E. A. Pence P. A. Yantis P. C. Kirkland R. A. Dobie

1989-01-01

345

Characterization of Neural Breathing Pattern in Spontaneously Breathing Preterm Infants  

PubMed Central

The aim was to characterize the neural breathing pattern in non-intubated preterm infants. The diaphragm electrical activity (EAdi) and heart rate were simultaneously measured repeatedly for 1 hour over several days using a modified feeding tube equipped with miniaturized sensors. The EAdi waveform was quantified for phasic and tonic activity, neural timings, and prevalence of recurring patterns, including central apnea. Ten infants with mean age 7 days (range 313) were studied. Their birth weight was 1512 g (11581800g), and gestational age (GA) at birth 31 weeks (2836). Neural inspiratory and expiratory times were 278 ms (195450 ms) and 867 ms (6681436 ms), and correlated with GA (p<0.001). Tonic EAdi represented 29.5% of phasic EAdi (1640%), and was related to GA (r=0.61, p<0.001). For the group, 68% of the time was regular phasic breathing (without tonic activity), and 29% of the time with elevated tonic activity. Central apneas >5s occurred on average 10 times per hour (229). Heart rate reductions were correlated to central apnea duration. In conclusion, esophageal recordings of the EAdi waveform demonstrate that neural breathing pattern is variable, with regards to timing, amplitude and pattern with a distinct amount of tonic diaphragm activity.

Beck, Jennifer; Reilly, Maureen; Grasselli, Giacomo; Qui, Haibo; Slutsky, Arthur S.; Dunn, Michael S.; Sinderby, Christer A.

2011-01-01

346

Characterization of neural breathing pattern in spontaneously breathing preterm infants.  

PubMed

The aim was to characterize the neural breathing pattern in nonintubated preterm infants. The diaphragm electrical activity (EAdi) and heart rate were simultaneously measured repeatedly for 1 h over several days using a modified feeding tube equipped with miniaturized sensors. The EAdi waveform was quantified for phasic and tonic activity, neural timings, and prevalence of recurring patterns, including central apnea. Ten infants with mean age 7 d (range, 3-13 d) were studied. Their birth weight was 1512 g (1158-1800 g) and GA at birth 31 wk (28-36 wk). Neural inspiratory and expiratory times were 278 ms (195-450 ms) and 867 ms (668-1436 ms) and correlated with GA (p < 0.001). Tonic EAdi represented 29.5% of phasic EAdi (16-40%) and was related to GA (r = 0.61, p < 0.001). For the group, 68% of the time was regular phasic breathing (without tonic activity) and 29% of the time with elevated tonic activity. Central apneas >5 s occurred on average 10 times per hour (2-29). Heart rate reductions were correlated to central apnea duration. In conclusion, esophageal recordings of the EAdi waveform demonstrate that neural breathing pattern is variable, with regards to timing, amplitude, and pattern with a distinct amount of tonic diaphragm activity. PMID:21857389

Beck, Jennifer; Reilly, Maureen; Grasselli, Giacomo; Qui, Haibo; Slutsky, Arthur S; Dunn, Michael S; Sinderby, Christer A

2011-12-01

347

Astable Resonator Photoneutralization Apparatus.  

National Technical Information Service (NTIS)

Apparatus is described for photoneutralization of negatively charged atomic or molecular particles, using multiple passes of electronmagnetic radiation of predetermined wavelength. 8 figs. (ERA citation 13:057793)

J. H. Fink

1987-01-01

348

Apparatus for Teaching Physics  

ERIC Educational Resources Information Center

|Describes apparatus for demonstrating magnetic lines of force, plastic discharge tubes, minimum angle of deviation of light passing through a prism, light scattering, and measuring high voltage. (SL)|

Gottlieb, Herbert H., Ed.

1978-01-01

349

Battery cell feedthrough apparatus  

DOEpatents

A compact, hermetic feedthrough apparatus comprising interfitting sleeve portions constructed of chemically-stable materials to permit unique battery designs and increase battery life and performance.

Kaun, Thomas D. (New Lenox, IL)

1995-01-01

350

Fluid-structure coupled analysis of underwater cylindrical shells  

Microsoft Academic Search

Underwater cylindrical shell structures have been found a wide of application in many engineering fields, such as the element\\u000a of marine, oil platforms, etc. The coupled vibration analysis is a hot issue for these underwater structures. The vibration\\u000a characteristics of underwater structures are influenced not only by hydrodynamic pressure but also by hydrostatic pressure\\u000a corresponding to different water depths. In

Shang-Mao Ai; Li-Ping Sun

2008-01-01

351

Optimization of Energy Efficient Transmission in Underwater Sensor Networks  

Microsoft Academic Search

Underwater communication is a challenging topic due to its singular channel\\u000acharacteristics. Most protocols used in terrestrial wireless communication can\\u000anot be directly applied in the underwater world. In this paper, we focus on the\\u000aissue of energy efficient transmission in underwater sensor networks (UWSNs)\\u000aand analyze this problem in a rigorous and theoretical way. We formalize an\\u000aoptimization problem

Hongkun Yang; Bin Liu; Fengyuan Ren; Hao Wen; Chuang Lin

2009-01-01

352

Study of archaeological underwater finds: deterioration andconservation  

Microsoft Academic Search

This study is aimed at an assessment of the methodologies, instruments and new applications for underwater archaeology. Research\\u000a focused on study of the various kinds of degradation affecting underwater finds and stone materials aged in underwater environment,\\u000a efficiency evaluation of various surface cleaning methods and study and mixing of protective products with consolidating resins\\u000a and antimicrobial biocides to be applied

G. M. Crisci; M. F. La Russa; M. Macchione; M. Malagodi; A. M. Palermo; S. A. Ruffolo

2010-01-01

353

Features of underwater acoustics from Aristotle to our time  

Microsoft Academic Search

Underwater acoustics has been one of the fastest growing fields of research in acoustics. In particular, the 20th Century\\u000a has taken our understanding of underwater acoustics phenomena a great step forward. The two World Wars contributed to the\\u000a recognition of the importance of research in underwater acoustics, and the momentum in research and development gained during\\u000a World War II did

Leif Bjrn

2003-01-01

354

Underwater Sensor Networks: A New Energy Efficient and Robust Architecture  

PubMed Central

The specific characteristics of underwater environments introduce new challenges for networking protocols. In this paper, a specialized architecture for underwater sensor networks (UWSNs) is proposed and evaluated. Experiments are conducted in order to analyze the suitability of this protocol for the subaquatic transmission medium. Moreover, different scheduling techniques are applied to the architecture in order to study their performance. In addition, given the harsh conditions of the underwater medium, different retransmission methods are combined with the scheduling techniques. Finally, simulation results illustrate the performance achievements of the proposed protocol in end-to-end delay, packet delivery ratio and energy consumption, showing that this protocol can be very suitable for the underwater medium.

Climent, Salvador; Capella, Juan Vicente; Meratnia, Nirvana; Serrano, Juan Jose

2012-01-01

355

Underwater oil detection experiment by laser fluorescence remote sensing  

NASA Astrophysics Data System (ADS)

Spilled oil is one of the most serious marine environment disasters, which damaged ecological environment seriously with long-term and large-scale impact. Based on the experiment and research in the Canadian Centre of Environmental Technology, an experiment is taken to detect the underwater suspended oil-spills by Laser-induced fluorescence. It quantizes the conditions that Laser-induced fluorescence can be used to detect underwater oil, and makes a solid theory foundation for the system design of underwater oil detection by Laser-induced fluorescence. This environmental solves a key problem for underwater oil detection by Laser-induced fluorescence.

An, Jubai; Yang, Rongrong; Liu, Zhaoxia

2010-10-01

356

Underwater shock focusing by composite structures  

NASA Astrophysics Data System (ADS)

Underwater explosions are threats to the structural integrity of naval vessels. In particular, if a convergent section is present on the vessel, the shock wave can focus and produce extremely high pressures near the focal region. Based on previous research on converging shock waves, a logarithmic spiral duct is considered to be an efficient shape to focus shock waves onto the focal region. Here, underwater shock tests on logarithmic spiral-shaped structures made of plastic, metal and fiber composites are conducted. High-speed schlieren photography is used to visualize the shock waves. Simultaneously, ultrafast pressure readings are recorded by laboratory- made pressure sensors, which are able to measure pressures up to 10 GPa. Comparisons between the various types of surrounding materials will be presented. The results can explore the use of composite materials in future marine applications.

Wang, Chuanxi; Eliasson, Veronica

2011-11-01

357

Detecting underwater improvised explosive threats (DUIET)  

NASA Astrophysics Data System (ADS)

Improvised Explosive Devices (IEDs) have presented a major threat in the wars in Afghanistan and Iraq. These devices are powerful homemade land mines that can be small and easily hidden near roadsides. They are then remotely detonated when Coalition Forces pass by either singly or in convoys. Their rapid detection, classification and destruction is key to the safety of troops in the area. These land based bombs will have an analogue in the underwater theater especially in ports, lakes, rivers and streams. These devices may be used against Americans on American soil as an element of the global war on terrorism (GWOT) Rapid detection and classification of underwater improvised explosive devices (UIED) is critical to protecting innocent lives and maintaining the day to day flow of commerce. This paper will discuss a strategy and tool set to deal with this potential threat.

Feeley, Terry

2010-04-01

358

Multipath correlations in underwater acoustic communication channels.  

PubMed

Uncorrelated scattering (US), which assumes that multipath arrivals undergo uncorrelated scattering and are thus uncorrelated, has been the standard model for digital communications including underwater acoustic communications. This paper examines the cross-correlation of multipath arrivals based on at-sea data with different temporal coherence time, assuming quasi-stationary statistics. It is found that multipath arrivals are highly cross-correlated when the channel is temporally coherent, and are uncorrelated when the channel is temporally incoherent. A theoretical model based on the path phase rates and relative-phase fluctuations is used to explain experimentally observed phenomena, assuming the path amplitudes vary slowly compared with the phases. The implications of correlated scattering for underwater acoustic communication channel tracking are discussed. PMID:23556587

Huang, S H; Yang, T C; Huang, Chen-Fen

2013-04-01

359

Underwater Laser Plasma with Reactive Fuels  

NASA Astrophysics Data System (ADS)

This paper discusses the application of a nanosecond laser-shock to induce a cavitation bubble in a suspension of water and aluminum and an underwater ablation event at an aluminum target to generate the conditions under which metal fuels will oxidize with water. The energy deposited into the plasma is varied with laser energy, allowing for a laboratory-scale setting where particle reactivity can be investigated. In the case of suspended aluminum fuel particles, the bubble dynamics (expansion radius and period) are augmented by the presence of the reactive particles. Laser ablation at an aluminum surface is also accompanied by fast oxidation, augmenting the bubble formation. High-speed framing camera images along with time-resolved emission spectra are used to monitor bubble dynamics and reactivity. The critical conditions necessary to promote underwater reactivity of fuels in this laboratory setting will be used to guide future applications of reactive materials.

Carney, Joel; Piecuch, Scott

2011-06-01

360

Cymbal piezoelectric composite underwater acoustic transducer.  

PubMed

The working principle of Cymbal piezoelectric composite underwater acoustic transducer was studied in this paper. PZT-5A piezoelectric ceramic disk was used as piezoelectric phase and brass foil was used as end cap electrode of the Cymbal transducer. The silicon rubber was used as the insulated proof layer of the underwater acoustic transducer. The properties of this transducer used as hydrophone, such as operation frequency, free-field voltage receiving sensitivity and directivity, were investigated. Several kinds of prototype of this transducer were fabricated and the properties of this transducer used as hydrophone were tested. The results show that the properties of this transducer used as hydrophone depend on the dimensions of Cymbal transducer because the piezoelectric properties of this transducer are dependent on the dimensions of Cymbal transducer's end caps. The appropriate dimensions for getting higher free-field voltage receiving sensitivity with -184.7 dB were obtained. PMID:16793099

Li, Denghua; Wu, Min; Oyang, Peixi; Xu, Xiaofei

2006-06-06

361

Autonomous underwater systems for survey operations  

NASA Astrophysics Data System (ADS)

An autonomous underwater vehicle (AUV) that can be released at sea, find a harbor, perform a task, and return to a designated location is highly desirable. The military applications of such a system are obvious. Mine clearing and mine laying come to mind. Other applications could include oceanographic surveys, mineral exploration, fish population studies, and underwater equipment repair. In 1987, the Naval Surface Weapons Center (NSWC) posed the development of such a vehicle as a research problem, and asked the NOAA Office of Sea Grant to recommend several Sea Grant Institutions with expertise in AUVs to investigate. MIT Sea Grant was invited to submit a proposal and was one of three Sea Grant Programs awarded a one-year grant by NSWC. The study developed a vehicle concept and outlined a plan of research necessary for its development. The findings of the MIT research team are summarized here.

Doelling, Norman; Gowell, Elizabeth T.

1987-06-01

362

Design for Underwater Aplanatic Acoustic Mirror  

NASA Astrophysics Data System (ADS)

Underwater acoustic lenses are useful devices for underwater imaging because of their small dimension and low power consumption but have a problem under the condition of changing water temperature because the refractive index depends on the water temperature. To solve this problem, we propose aplanatic acoustic mirrors, which consist of two aspherical mirrors and can remove spherical and coma aberrations. These mirrors are designed by a method used in the Ritchey Chrtien astronomical telescopes. The aplanatic mirror shows a larger focal sound pressure and better temperature characteristic than an aplanatic acoustic lens but has a narrow field of angle. Then, an off-axis aplanatic mirror, which consists of two aspherical off-axis mirrors, is designed by extraction of parts from a normal aplanatic mirror to obtain a wider field of angle.

Yuji Sato,; Koichi Mizutani,; Naoto Wakatsuki,; Toshiaki Nakamura,

2010-07-01

363

Breathing patterns in nonlinear relaxation  

NASA Astrophysics Data System (ADS)

In numerical experiments involving nonlinear solitary waves propagating through nonhomogeneous media one observes 'breathing' in the sense of the amplitude of the wave going up and down on a much faster scale than the motion of the wave. In this paper we investigate this phenomenon in the simplest case of stationary waves in which the evolution corresponds to relaxation to a nonlinear ground state. The particular model is the popular ?0 impurity in the cubic nonlinear Schrdinger equation on the line. We give asymptotics of the amplitude on a finite but relevant time interval and show their remarkable agreement with numerical experiments. We stress the nonlinear origin of the 'breathing patterns' caused by the selection of the ground state depending on the initial data, and by the nonnormality of the linearized operator.

Holmer, Justin; Zworski, Maciej

2009-06-01

364

Adaptive setpoint control for autonomous underwater vehicles  

Microsoft Academic Search

In this paper, we propose an adaptive saturated proportional-derivative (SP-D) setpoint controller for autonomous underwater vehicles. The proposed controller does not require any knowledge of the inertia matrix, Coriolis and centripetal force, hydrodynamic damping, and parameters of the gravity and buoyancy forces. The structure of this setpoint controller is based on the SP-D feedback, plus an adaptive update law for

Y. C. Sun; C. C. Cheah

2003-01-01

365

Optimal and adaptive control of underwater vehicles  

Microsoft Academic Search

This article contains a continuous-time optimal and adaptive control scheme for underwater vehicles moving in 6 d.o.f. The control scheme is an modification of the algorithm of Johansson. The algorithm is optimal in the sense that it minimizes the state errors and the forces which contribute to the vehicle's kinetic energy that is spent to correct these errors. The performance

Svein I. Sagatun; Rolf Johansson

1995-01-01

366

Underwater sensor networks: applications, advances and challenges.  

PubMed

This paper examines the main approaches and challenges in the design and implementation of underwater wireless sensor networks. We summarize key applications and the main phenomena related to acoustic propagation, and discuss how they affect the design and operation of communication systems and networking protocols at various layers. We also provide an overview of communications hardware, testbeds and simulation tools available to the research community. PMID:22124087

Heidemann, John; Stojanovic, Milica; Zorzi, Michele

2012-01-13

367

Numerical simulation of underwater explosion loads  

Microsoft Academic Search

Numerical simulation of TNT underwater explosion was carried out with AUTODYN software. Influences of artificial viscosity\\u000a and mesh density on simulation results were discussed. Detonation waves in explosive and shock wave in water during early\\u000a time of explosion are high frequency waves. Fine meshes (less than 1,mm) in explosive and water nearby, and small linear viscosity\\u000a coefficients and quadratic viscosity

Chunliang Xin; Gengguang XU; Kezhong Liu

2008-01-01

368

Active control for installation of underwater structures  

Microsoft Academic Search

The trend towards deepwater development requires a new approach to underwater installation of offshore structures. The present\\u000a method using crane vessels has some drawbacks in operations at more than 2000 m depth. The natural period of the coupled system\\u000a of the rigged structure and the crane vessel becomes longer, so that it is no longer possible to manipulate the cranes

Keisuke Watanabe; Hideyuki Suzuki; Koichiro Yoshida

1998-01-01

369

Coral World Ocean Park & Underwater Observatory  

NSDL National Science Digital Library

Award-winning tourist attraction in St. Thomas, Virgin Islands, focuses completely on Caribbean reef and island life. Aquarium exhibits include: Underwater Observatory built into the fringing reef; predators tank with sharks, barracuda, moray eels and tarpon; Caribbean Reef Encounter offering interpretive programs; tanks housing smaller reef fishes and invertebrates; as well as touch pool, shark shallows, stingray and turtle pools. Nature walks highlight native plant life and iguanas. Water sports available. Admission fees apply.

370

NON-LINER DYNAMICS OF UNDERWATER ACOUSTICS  

Microsoft Academic Search

The non-linear dynamic behavior of acoustic wave propagation in an underwater sound channel, described by the Munk's classical sound speed profile perturbed by a single-mode internal wave, is studied using a parabolic ray theory. The amplitude and wavelength of this single-mode wave are used as the branching parameters in bifurcation analysis. The phase plane trajectory of the ray-based system can

M. Wiercigroch; M. Badiey; J. Simmen; A. H.-D. Cheng

1999-01-01

371

Video Captures Underwater 'Brimstone and Fire'  

NSDL National Science Digital Library

This story from National Public Radio highlights NOAA's unusually close observations of an underwater volcano in the northern Pacific Ocean, close to a subduction zone near the Mariana Islands. After locating the volcano in 2004, the crew returned in 2006 to witness and record an eruption. Robotic vehicles were able to get closer than anyone has ever been to an active volcano. Links on the page take interested viewers to two videos and more information on this expedition.

Joyce, Christopher; Radio, National P.

372

Adaptive autonomous underwater vehicles for littoral surveillance  

Microsoft Academic Search

Autonomous underwater vehicles (AUVs) have gained more interest in recent years for military as well as civilian applications.\\u000a One potential application of AUVs is for the purpose of undersea surveillance. As research into undersea surveillance using\\u000a AUVs progresses, issues arise as to how an AUV acquires, acts on, and shares information about the undersea battle space.\\u000a These issues naturally touch

Stephanie Kemna; Michael J. Hamilton; David T. Hughes; Kevin D. LePage

373

Laser 3-D measuring system and real-time visual feedback for teaching and correcting breathing.  

PubMed

We present a novel method for real-time 3-D body-shape measurement during breathing based on the laser multiple-line triangulation principle. The laser projector illuminates the measured surface with a pattern of 33 equally inclined light planes. Simultaneously, the camera records the distorted light pattern from a different viewpoint. The acquired images are transferred to a personal computer, where the 3-D surface reconstruction, shape analysis, and display are performed in real time. The measured surface displacements are displayed with a color palette, which enables visual feedback to the patient while breathing is being taught. The measuring range is approximately 400600500 mm in width, height, and depth, respectively, and the accuracy of the calibrated apparatus is 0.7 mm. The system was evaluated by means of its capability to distinguish between different breathing patterns. The accuracy of the measured volumes of chest-wall deformation during breathing was verified using standard methods of volume measurements. The results show that the presented 3-D measuring system with visual feedback has great potential as a diagnostic and training assistance tool when monitoring and evaluating the breathing pattern, because it offers a simple and effective method of graphical communication with the patient. PMID:22502562

Povi?, Klemen; Flear, Matja; Moina, Janez; Jezerek, Matija

2012-03-01

374

Laser 3-D measuring system and real-time visual feedback for teaching and correcting breathing  

NASA Astrophysics Data System (ADS)

We present a novel method for real-time 3-D body-shape measurement during breathing based on the laser multiple-line triangulation principle. The laser projector illuminates the measured surface with a pattern of 33 equally inclined light planes. Simultaneously, the camera records the distorted light pattern from a different viewpoint. The acquired images are transferred to a personal computer, where the 3-D surface reconstruction, shape analysis, and display are performed in real time. The measured surface displacements are displayed with a color palette, which enables visual feedback to the patient while breathing is being taught. The measuring range is approximately 400600500 mm in width, height, and depth, respectively, and the accuracy of the calibrated apparatus is +/-0.7 mm. The system was evaluated by means of its capability to distinguish between different breathing patterns. The accuracy of the measured volumes of chest-wall deformation during breathing was verified using standard methods of volume measurements. The results show that the presented 3-D measuring system with visual feedback has great potential as a diagnostic and training assistance tool when monitoring and evaluating the breathing pattern, because it offers a simple and effective method of graphical communication with the patient.

Povi?, Klemen; Flear, Matja; Moina, Janez; Jezerek, Matija

2012-03-01

375

Biosensor UUV payload for underwater detection  

NASA Astrophysics Data System (ADS)

Increased emphasis on maritime domain awareness and port security has led to the development of unmanned underwater vehicles (UUVs) capable of extended missions. These systems rely most frequently on well-developed side scan sonar and acoustic methods to locate potential targets. The Naval Research Laboratory (NRL) is developing biosensors for underwater explosives detection that complement acoustic sensors and can be used as UUV payloads to monitor areas for port and harbor security or in detection of underwater unexploded ordnance (UXO) and biochemical threats. The prototype sensor has recently been demonstrated to detect explosives in seawater at trace levels when run in a continuous sampling mode. To overcome ongoing issues with sample preparation and facilitate rapid detection at trace levels in a marine environment, we have been developing new mesoporous materials for in-line preconcentration of explosives and other small molecules, engineering microfluidic components to improve the signal, and testing alternative signal transduction methods. Additional work is being done to optimize the optical components and sensor response time. Highlights of these current studies and our ongoing efforts to integrate the biosensor with existing detection technologies to reduce false positives are described. In addition, we present the results of field tests that demonstrate the prototype biosensor performance as a UUV payload.

Kusterbeck, Anne W.; Charles, Paul T.; Melde, Brian J.; Trammell, Scott A.; Adams, Andr A.; Deschamps, Jeffrey R.

2010-04-01

376

Design for Underwater Aplanatic Straubel Acoustic Mirror  

NASA Astrophysics Data System (ADS)

An aplanatic Fresnel lens was developed in a previous study to reduce the thickness of underwater acoustic lenses. Showing better convergence properties than aplanatic biconvex and hyperbolic Fresnel lenses, the aplanatic Fresnel lens had limitations in terms of frequency and number of waves owing to its shape. An underwater aplanatic Straubel acoustic mirror, the concept o which is based on a Straubel mirror, was designed to remove the two limitations of aplanatic Fresnel lenses. When the lens is used for underwater imaging sonar, the range resolution deteriorates because of these problems. The shape of the aplanatic Straubel mirror was designed using a numerical optimization method, and its convergence properties were evaluated in simulations. The mirror could correct spherical and coma aberrations in accordance with ray theory. In a comparison of the aplanatic Straubel mirror with an aplanatic Fresnel lens, the mirror had less coma aberration and field curvature than the lens. Additionally, the aplanatic Straubel mirror did not have the two limitations of the lens. Therefore, the aplanatic Straubel mirror showed better convergence than the aplanatic Fresnel lens.

Sato, Yuji; Mizutani, Koichi; Wakatsuki, Naoto; Nakamura, Toshiaki

2011-07-01

377

Cooling and heating apparatus  

Microsoft Academic Search

This patent describes an energy transfer apparatus for transferring energy from and to a source liquid to heat and cool a facility, the apparatus comprising: means for providing a refrigerant cycle including means for evaporating refrigerant, means for condensing refrigerant and means for producing a phase change in the refrigerant; means for cooling air; means for providing a single continuous

Dittell

1987-01-01

378

Apparatus for Teaching Physics.  

ERIC Educational Resources Information Center

|Describes: (1) a variable inductor suitable for an inductance-capacitance bridge consisting of a fixed cylindrical solenoid and a moveable solenoid; (2) long-range apparatus for demonstrating falling bodies; and (3) an apparatus using two lasers to demonstrate ray optics. (SK)|

Gottlieb, Herbert H., Ed.

1981-01-01

379

Laser beam generating apparatus  

DOEpatents

Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect).

Warner, Bruce E. (Livermore, CA); Duncan, David B. (Auburn, CA)

1993-01-01

380

Laser beam generating apparatus  

DOEpatents

Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect).

Warner, Bruce E. (Livermore, CA); Duncan, David B. (Auburn, CA)

1994-01-01

381

Laser beam generating apparatus  

DOEpatents

Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus is described. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect). 7 figures.

Warner, B.E.; Duncan, D.B.

1994-02-15

382

Laser beam generating apparatus  

DOEpatents

Laser beam generating apparatus including a septum segment disposed longitudinally within the tubular structure of the apparatus. The septum provides for radiatively dissipating heat buildup within the tubular structure and for generating relatively uniform laser beam pulses so as to minimize or eliminate radial pulse delays (the chevron effect). 11 figures.

Warner, B.E.; Duncan, D.B.

1993-12-28

383

Bearing Lubrication Apparatus.  

National Technical Information Service (NTIS)

The patent described apparatus for lubrication of anti-friction bearings which uses the oil bleeding characteristics of grease. The apparatus consists of a housing for attachment to a bearing and a grease reservoir wherein the grease is retained in a slop...

K. H. Warren

1970-01-01

384

Flow line filter apparatus  

Microsoft Academic Search

An apparatus is described for filtering drilling mud that is recirculated out of a well casing. The apparatus includes: a. a flow conveying tubular section, sealably attachable at its first lower end to the well casing for allowing fluid flow therethrough and open-ended at its top portion; b. an outer tank portion being at least twice the diameter of the

Gardes

1986-01-01

385

Thermal protection apparatus  

DOEpatents

An apparatus which thermally protects sensitive components in tools used in a geothermal borehole. The apparatus comprises a Dewar within a housing. The Dewar contains heat pipes such as brass heat pipes for thermally conducting heat from heat sensitive components to a heat sink such as ice.

Bennett, Gloria A. (Los Alamos, NM); Elder, Michael G. (Los Alamos, NM); Kemme, Joseph E. (Albuquerque, NM)

1985-01-01

386

Thermal protection apparatus  

DOEpatents

The disclosure is directed to an apparatus for thermally protecting sensitive components in tools used in a geothermal borehole. The apparatus comprises a Dewar within a housing. The Dewar contains heat pipes such as brass heat pipes for thermally conducting heat from heat sensitive components such as electronics to a heat sink such as ice.

Bennett, G.A.; Elder, M.G.; Kemme, J.E.

1984-03-20

387

Pulse combustion apparatus  

Microsoft Academic Search

A pulse combustion apparatus is described which includes: a combustion chamber; an exhaust system including an exhaust pipe forming a resonant system with the combustion chamber and a generally cylindrical exhaust cushion chamber downstream of the exhaust pipe for receiving combustion gases from the pipe and communicating with an exhaust outlet form the apparatus; means for delivering successive fuel charges

Kitchen

1986-01-01

388

Human breath analysis: methods for sample collection and reduction of localized background effects.  

PubMed

Solid-phase microextraction (SPME) was applied, in conjunction with gas chromatography-mass spectrometry, to the analysis of volatile organic compounds (VOCs) in human breath samples without requiring exhaled breath condensate collection. A new procedure, exhaled breath vapor (EBV) collection, involving the active sampling and preconcentration of a breath sample with a SPME fiber fitted inside a modified commercial breath-collection device, the RTube, is described. Immediately after sample collection, compounds are desorbed from the SPME fiber at 250 degrees C in the GC-MS injector. Experiments were performed using EBV collected at -80 degrees C and at room temperature, and the results compared to the traditional method of collecting exhaled breath condensate at -80 degrees C followed by passive SPME sampling of the collected condensate. Methods are compared in terms of portability, ease-of-use, speed of analysis, and detection limits. The need for a clean air supply for the study subjects is demonstrated using several localized sources of VOC contaminants including nail polish, lemonade, and gasoline. Various simple methods to supply clean inhaled air to a subject are presented. Chemical exposures are used to demonstrate the importance of providing cleaned air (organic vapor respirator) or an external air source (tubing stretched to a separate room). These techniques allow for facile data interpretation by minimizing background contaminants. It is demonstrated herein that this active SPME breath-sampling device provides advantages in the forms of faster sample collection and data analysis, apparatus portability and avoidance of power or cooling requirements, and performance for sample collection in a contaminated environment. PMID:19844696

Martin, Audrey N; Farquar, George R; Jones, A Daniel; Frank, Matthias

2009-10-22

389

Kidney motion during free breathing and breath hold for MR-guided radiotherapy.  

PubMed

Current treatments for renal cell carcinoma have a high complication rate due to the invasiveness of the treatment. With the MRI-linac it may be possible to treat renal tumours non-invasively with high-precision radiotherapy. This is expected to reduce complications. To deliver a static dose distribution, radiation gating will be used. In this study the reproducibility and efficiency of free breathing gating and a breath hold treatment of the kidney was investigated. For 15 patients with a renal lesion the kidney motion during 2min of free breathing and 10 consecutive expiration breath holds was studied with 2D cine MRI. The variability in kidney expiration position and treatment efficiency for gating windows of 1 to 20mm was measured for both breathing patterns. Additionally the time trend in free breathing and the variation in expiration breath hold kidney position with baseline shift correction was determined. In 80% of the patients the variation in expiration position during free breathing is smaller than 2mm. No clinically relevant time trends were detected. The variation in expiration breath hold is for all patients larger than the free breathing expiration variation. Gating on free breathing is, for gating windows of 1 to 5mm more efficient than breath hold without baseline correction. When applying a baseline correctionto the breath hold it increases the treatment efficiency. The kidney position is more reproducible in expiration free breathing than non-guided expiration breath hold. For small gating windows it is also more time efficient. Since free breathing also seems more comfortable for the patients it is the preferred breathing pattern for MRI-Linac treatments of the kidney. PMID:23475278

Stam, Mette K; van Vulpen, Marco; Barendrecht, Maurits M; Zonnenberg, Bernard A; Intven, Martijn; Crijns, Sjoerd P M; Lagendijk, Jan J W; Raaymakers, Bas W

2013-03-11

390

Kidney motion during free breathing and breath hold for MR-guided radiotherapy  

NASA Astrophysics Data System (ADS)

Current treatments for renal cell carcinoma have a high complication rate due to the invasiveness of the treatment. With the MRI-linac it may be possible to treat renal tumours non-invasively with high-precision radiotherapy. This is expected to reduce complications. To deliver a static dose distribution, radiation gating will be used. In this study the reproducibility and efficiency of free breathing gating and a breath hold treatment of the kidney was investigated. For 15 patients with a renal lesion the kidney motion during 2 min of free breathing and 10 consecutive expiration breath holds was studied with 2D cine MRI. The variability in kidney expiration position and treatment efficiency for gating windows of 1 to 20 mm was measured for both breathing patterns. Additionally the time trend in free breathing and the variation in expiration breath hold kidney position with baseline shift correction was determined. In 80% of the patients the variation in expiration position during free breathing is smaller than 2 mm. No clinically relevant time trends were detected. The variation in expiration breath hold is for all patients larger than the free breathing expiration variation. Gating on free breathing is, for gating windows of 1 to 5 mm more efficient than breath hold without baseline correction. When applying a baseline correction to the breath hold it increases the treatment efficiency. The kidney position is more reproducible in expiration free breathing than non-guided expiration breath hold. For small gating windows it is also more time efficient. Since free breathing also seems more comfortable for the patients it is the preferred breathing pattern for MRI-Linac treatments of the kidney.

Stam, Mette K.; van Vulpen, Marco; Barendrecht, Maurits M.; Zonnenberg, Bernard A.; Intven, Martijn; Crijns, Sjoerd P. M.; Lagendijk, Jan J. W.; Raaymakers, Bas W.

2013-04-01

391

Monotone Signal Segments Analysis as a novel method of breath detection and breath-to-breath interval analysis in rat  

PubMed Central

We applied a novel approach to respiratory waveform analysis - Monotone Signal Segments Analysis (MSSA) on 6-h recordings of respiratory signals in rats. To validate MSSA as a respiratory signal analysis tool we tested it by detecting: breaths and breath-to-breath intervals; by detecting respiratory timing and volume modes; and by detecting changes in respiratory pattern caused by lesions of monoaminergic systems in rats. MSSA differentiated three respiratory timing (tachypneic, eupneic, bradypneic-apneic), and three volume (artifacts, normovolemic, hypervolemic-sighs) modes. Lesion-induced respiratory pattern modulation was visible as shifts in the distributions of monotone signal segment amplitudes, and of breath-to-breath intervals. Specifically, noradrenergic lesion induced an increase in mean volume (p ? 0.03), with no change of the mean breath-to-breath interval duration (p ? 0.06). MSSA of timing modes detected noradrenergic lesion-induced interdependent changes in the balance of eupneic (decrease; p ? 0.02), and tachypneic (an increase; p ? 0.02) breath intervals with respect to control. In terms of breath durations within each timing mode, there was a tendency toward prolongation of the eupneic (p ? 0.08) and bradypneic-apneic (p ? 0.06) intervals. These results demonstrate that MSSA is sensitive to subtle shifts in respiratory rhythmogenesis not detectable by simple respiratory pattern descriptive statistics. MSSA represents a potentially valuable new tool for investigations of respiratory pattern control.

Bojic, Tijana; Saponjic, Jasna; Radulovacki, Miodrag; Carley, David W.; Kalauzi, Aleksandar

2008-01-01

392

Instrument for underwater high-angular resolution volume scattering function measurements  

NASA Astrophysics Data System (ADS)

A prototype instrument for in situ measurements of the volume scattering function (VSF) and the beam attenuation of water has been built and tested in the EOO laboratory. The intended application of the instrument is the enhancement of Navy operational optical systems for finding and imaging underwater objects such as mines. A description of the apparatus that was built and preliminary laboratory data will be presented. The instrument measures the VSF, (beta) ((theta) ), near the optical axis in both the forward and back directions from approximately 0.2 degrees off axis to approximately 5 degrees in 0.1 degree steps and at side angles of 45 degrees, 90 degrees, and 135 degrees. A diode- pumped, frequency-doubled, Nd:YAG laser provides the 532 nm light. This is the most used wavelength for underwater optical systems. The forward and back scattered light is collected and focused to a plane where scattering angles in the water are mapped onto concentric rings. At this focal plane, a conical reflector compresses the annular optical data onto a line along the cone axis where it is read by a MOS linear image array providing over 500 separate angular measurements. The beam attenuation coefficient, c, is also measured by means of a unique dual path configuration.

Dueweke, Paul W.; Bolstad, Jay; Leonard, Donald A.; Sweeney, Harold E.; Boyer, Philip A.; Winkler, Erik M.

1997-02-01

393

Instrumentation and Sensors for Human Breath Analysis  

Microsoft Academic Search

Exhaled breath contains a vast milieu of compounds, both volatile and non-volatile, that appear to correlate with physiological\\u000a processes on-going in the body. These breath biomarkers hold enormous diagnostic potential when they are adequately measured\\u000a and monitored. Thus, instrumentation geared towards breath analysis applications has expanded rapidly in the last decade,\\u000a although challenges for future research still exist. This chapter

Melinda G. Simon; Cristina E. Davis

394

Breathing-control lowers blood pressure  

Microsoft Academic Search

We hypothesise that routinely applied short sessions of slow and regular breathing can lower blood pressure (BP). Using a new technology BIM (Breathe with Interactive Music), hypertensive patients were guided towards slow and regular breathing. The present study evaluates the efficacy of the BIM in lowering BP. We studied 33 patients (23M\\/10F), aged 2575 years, with uncontrolled BP. Patients were

E Grossman; A Grossman; MH Schein; R Zimlichman; B Gavish

2001-01-01

395

Decompression Sickness Following Breath-hold Diving  

Microsoft Academic Search

Despite convincing evidence of a relationship between breath-hold diving and decompression sickness (DCS), the causal connection is only slowly being accepted. Only the more recent textbooks have acknowledged the risks of repetitive breath-hold diving. We compare four groups of breath-hold divers: (1) Japanese and Korean amas and other divers from the Pacific area, (2) instructors at naval training facilities, (3)

J. D. Schipke; E. Gams; Oliver Kallweit

2006-01-01

396

Sleep and breathing in neuromuscular disease  

Microsoft Academic Search

ABSTRACT: Respiratory muscle weakness,in neuromuscular,disease causes significant morbidity,and,mortality. The published,data,on respiratory,muscle,activity and breathing during sleep in normal subjects, the impact of respiratory muscle weakness on sleep and breathing and the relations to daytime respiratory function in neuromuscular disease are reviewed,here. In normal,subjects during,sleep upper airway,resistance increases, chemosensitivity is reduced and the wakefulness drive to breathe is lost, resulting in a

S. C. Bourke; G. J. Gibson

2002-01-01

397

Development of a control system for an Autonomous Underwater Vehicle  

Microsoft Academic Search

This work proposes the development of a control system for an autonomous underwater vehicle dedicated to the observation of the oceans. The vehicle, a hybrid between Autonomous Underwater Vehicles (AUVs) and Autonomous Surface Vehicles (ASV), moves on the surface of the sea and makes vertical immersions to obtain profiles of a water column, according to a pre-established plan. The displacement

I. Masmitja; G. Masmitja; J. Gonzalez; S. Shariat-Panahi; S. Gomariz

2010-01-01

398

Motion Control System of Underwater Robot without Rudder and Wing  

Microsoft Academic Search

Motion control system of underwater robot without rudder and wing is presented with hardware and software architecture. Considering coupling effects and thrust reduction of propellers, the control layer, perception layer and executive layer in underwater robot system architecture are modified. In control layer, a nonlinear controller is presented to handle coupling effects between the longitudinal dimension and other dimensions of

Yong Gan; Yushan Sun; Lei Wan; Yongjie Pang

2006-01-01

399

Underwater performance of flexible microgripper and fine particle manipulation  

NASA Astrophysics Data System (ADS)

Underwater performance of the microfabricated flexible microgripper (FMG) using Lorentz force actuation and electrothermal bimorph actuation is presented here. The Lorentz force actuation was a primary factor of the actuation for the underwater operation of FMG. We have manipulated the polystyrene fine particles successfully by using the FMG in water.

Suzuki, Yoshihiko

1994-10-01

400

Some underwater sounds of the hippopotamus (hippopotamus amphibius)  

Microsoft Academic Search

Hippos have at least three categories of sounds they give underwater. The sounds are rarely audible on the surface, and there is little or no expiration of air when they are given. They include tonal whines that are associated with submissive behavior; a pulsed croak that is often heard when calves and sub?adults are interacting underwater; and click?like sounds that

William E. Barklow

1997-01-01

401

Toward large-area mosaicing for underwater scientific applications  

Microsoft Academic Search

Severe attenuation and backscatter of light fundamentally limits our ability to image extended underwater scenes. Generating a composite view or mosaic from multiple overlapping images is usually the most practical and flexible way around this limitation. In this paper, we look at the general constraints associated with imaging from underwater vehicles for scientific applications - low overlap, nonuniform lighting, and

Oscar Pizarro; Hanumant Singh

2003-01-01

402

Model predictive control of remotely operated underwater vehicles  

Microsoft Academic Search

This paper describes the implementation of a model predictive controller novel in an underwater robot vehicle. This work also shows the development of an underwater vehicle model that accounts for physical, hydrodynamic and restorative effects, while the damping coefficients are neglected in the prediction of the vehicle position and orientation. The vehicle kinematic and dynamic models are linearized and arranged

A. Molero; R. Dunia; J. Cappelletto; G. Fernandez

2011-01-01

403

Detection of quadratic phase coupling in shallow underwater channel  

Microsoft Academic Search

This paper addresses the problem of detection of quadratic phase coupling (QPC) at the receiver when the source signal has traversed through an underwater channel. The channel has been numerically modeled using normal mode theory In a bounded underwater channel, the phase associated with each frequency varies with range as well as due to the characteristics of the channel. We

Tanmay Roy; Arun Kumar; Rajendar Bahl

2002-01-01

404

Development of advanced Lithium-ion battery for underwater vehicle  

Microsoft Academic Search

Electric power storage is an important technology for all equipments of underwater vehicles however environmental pressure is high, the temperature is 5 degrees Celsius or less, and conditions are unsuitable for many chemical reactions in the deep sea. Battery capacity is mainly dependent on its mass; this means that the cruising range of underwater vehicles is proportional to the mass

T. Hyakudome; H. Yoshida; S. Ishibashi; T. Sawa; M. Nakamura

2011-01-01

405

Autonomous Towed Vehicle for Underwater Inspection in a Port Area  

Microsoft Academic Search

This paper discusses an autonomous towed vehicle for underwater inspection in a port area, in which a sea current is so fast and complex. The autonomous towed vehicle has three different navigation modes; towed mode, autonomous mode and kite mode, to assure safe and reliable inspection in such a port area. An autonomous underwater vehicle (AUV) is employed as a

Jin-kyu Choi; Hiroshi Sakai; Toshinari Tanaka

2005-01-01

406

An underwater towed electromagnetic source for geophysical exploration  

Microsoft Academic Search

Low-frequency electromagnetic methods are used in geophysical exploration to detect the magnetic field distortion between a transmitter and receiver produced by locally conductive bodies. Both ground and airborne systems are in current use. It is possible to similarly conduct underwater geophysical exploration by using an underwater towed source of electromagnetic radiation and a receiving magnetic or electric field detector. The

BARRY E. TOSSMAN; DAVID L. THAYER; WILLIAM A. SWARTZ

1979-01-01

407

The state of the art in underwater acoustic telemetry  

Microsoft Academic Search

Progress in underwater acoustic telemetry since 1982 is reviewed within a framework of six current research areas: (1) underwater channel physics, channel simulations, and measurements; (2) receiver structures; (3) diversity exploitation; (4) error control coding; (5) networked systems; and (6) alternative modulation strategies. Advances in each of these areas as well as perspectives on the future challenges facing them are

Daniel B. Kilfoyle; Arthur B. Baggeroer

2000-01-01

408

Overview of networking protocols for underwater wireless communications  

Microsoft Academic Search

Underwater wireless communications can enable many scientific, environmental, commercial, safety, and military applications. Wireless signal transmission is also crucial to remotely control instruments in ocean observatories and to enable coordination of swarms of autonomous underwater vehicles and robots, which will play the role of mobile nodes in future ocean observation networks by virtue of their flexibility and reconfigurability. To make

Dario Pompili; Ian F. Akyildiz

2009-01-01

409

Design of sensor nodes in underwater sensor networks  

Microsoft Academic Search

Since the mid of 1990s, terrestrial wireless sensor network is developing quickly. However, constrained by certain characteristics of underwater acoustic channel such as limited available bandwidth and large propagation delays, which means development of underwater sensor networks, the extension of the concept of terrestrial wireless sensor network in ocean application, lags behind that of terrestrial wireless sensor network. Besides, due

Yu Yang; Zhang Xiaomin; Peng Bo; Fu Yujing

2009-01-01

410

PULRP: Path Unaware Layered Routing Protocol for Underwater Sensor Networks  

Microsoft Academic Search

We propose a path unaware layered routing protocol (PULRP) for dense underwater 3D sensor networks. An uplink transmission is considered, where a set of underwater sensor nodes report events to the sink node. PURLP algorithm consists of two phases. In the first phase (layering phase), a layering structure is presented which is a set of concentric spheres, around a sink

Sarath Gopi; Kannan Kannan; Deepthi Chander; Uday B. Desai; S. N. Merchant

2008-01-01

411

Battery Lifetime Estimation and Optimization for Underwater Sensor Networks  

Microsoft Academic Search

Acoustic technology has been established as the exclusive technology that provides robust underwater communications for military and civilian applications. One particular civilian application of interest is the deployment of underwater acoustic sensor networks. The main challenges of deploying such a network are the cost and the limited battery resources of individual sensor nodes. Here, we provide a method that addresses

Raja Jurdak; Cristina Videira Lopes; Pierre Baldi

2006-01-01

412

Research on architecture for reconfigurable underwater sensor networks  

Microsoft Academic Search

In this paper, novel architecture for underwater sensor networks is presented. The nodes in sensor networks are divided into fixed nodes, mobile nodes. And there are three layers defined in the architecture; surface, underwater, bottom. Nodes composed of several basic function modules in different layers communicate and collaborate each other. In this architecture, the sensor networks also can change their

Shuo Wang; Min Tan

2005-01-01

413

An Underwater Sensor Network with Dual Communications, Sensing, and Mobility  

Microsoft Academic Search

This paper describes an underwater sensor network with dual communication and support for sensing and mobility. The nodes in the system are connected acoustically for broadcast communication using an acoustic modem we developed. The nodes are connected optically for higher speed point to point data transfers using an optical modem we developed. We describe the hardware details of the underwater

Carrick Detweiller; Iuliu Vasilescu; Daniela Rus

2007-01-01

414

On applying network coding to underwater sensor networks  

Microsoft Academic Search

High error rates and long propagation delays in underwater sen- sor networks call for efficient error-recovery schemes. We believe network coding is a promising technique for this purpose because of the broadcast nature of acoustic channels and computation ca- pabilities at the sensor nodes. In this paper, we design a network coding scheme for underwater sensor networks and explore its

Zheng Guo; Peng Xie; Jun-hong Cui; Bing Wang

2006-01-01

415

UDB: Using Directional Beacons for Localization in Underwater Sensor Networks  

Microsoft Academic Search

Underwater sensor networks (UWSN) are widely used in many applications, such as oceanic resource exploration, pollution monitoring, tsunami warnings and mine reconnaissance. In UWSNs, determining the location information of each sensor node is a critical issue, because many services are based on the localization results. In this paper, we introduce a novel underwater localization approach based on directional signals, which

Hanjiang Luo; Yiyang Zhao; Zhongwen Guo; Siyuan Liu; Pengpeng Chen; Lionel M. Ni

2008-01-01

416

Maximum Permissible Density of Simultaneous Transmissions in Underwater Sensor Networks  

Microsoft Academic Search

In this paper, the ratio of signal to interference for underwater acoustic channels is calculated. Based on this ratio, upper bounds on the maximum permissible density of simultaneous transmissions of underwater sensor networks that allows a certain probability of successful reception, in two different models, are determined. In the first model, the distance between source and destination is assumed to

Mohammad Sheikh Zefreh; Pejman Khadivi

2008-01-01

417

An efficient transmission scheme for underwater sensor networks  

Microsoft Academic Search

One of the fundamental differences between the terrestrial radio frequency (RF) signal and underwater acoustic signal is long propagation delay. This paper is contented with a MAC protocol for underwater sensor networks (USN) in which there are n sensor nodes in a transmission range W . Long propagation delay of the acoustic signal causes a serious problem for MAC protocol.

2009-01-01

418

Designing an Adaptive Acoustic Modem for Underwater Sensor Networks  

Microsoft Academic Search

There is a growing interest in using underwater networked systems for oceanographic applications. These networks often rely on acoustic communication, which poses a number of challenges for reliable data transmission. The underwater acoustic channel is highly variable; each link can experience vastly different conditions, which change according to environmental factors as well as the locations of the communicating nodes. This

Lingjuan Wu; Jennifer Trezzo; Diba Mirza; Paul Roberts; Jules Jaffe; Yangyuan Wang; Ryan Kastner

2012-01-01

419

Underwater Sensor Networks: A New Energy Efficient and Robust Architecture  

Microsoft Academic Search

The specific characteristics of underwater environments introduce new challenges for networking protocols. In this paper, a specialized architecture for underwater sensor networks (UWSNs) is proposed and evaluated. Experiments are conducted in order to analyze the suitability of this protocol for the subaquatic transmission medium. Moreover, different scheduling techniques are applied to the architecture in order to study their performance. In

Salvador Climent; Juan Vincente Capella; Nirvana Meratnia; Juan Jos Serrano

2012-01-01

420

An Improved Communications Model for Underwater Sensor Networks  

Microsoft Academic Search

Underwater sensor network deployment can be quite difficult and expensive, thus much of the early development is limited to simulation work. There are some underwater physical channel models available in various simulation tools, but they are often overly generalized and rely on assumptions about the ocean as a whole. They are not appropriate for practical applications, as the ocean is

Peter King; Ramachandran Venkatesan; Cheng Li

2008-01-01

421

Autonomous underwater vehicle control using reinforcement learning policy search methods  

Microsoft Academic Search

Autonomous underwater vehicles (AUV) represent a challenging control problem with complex, noisy, dynamics. Nowadays, not only the continuous scientific advances in underwater robotics but the increasing number of subsea missions and its complexity ask for an automatization of submarine processes. This paper proposes a high-level control system for solving the action selection problem of an autonomous robot. The system is

A. El-Fakdi; M. Carreras; N. Palomeras; P. Ridao

2005-01-01

422

Control of Underwater Autonomous Vehicles Using Neural Networks  

Microsoft Academic Search

This paper describes a control method for low level control of autonomous underwater vehicles using a neural network approach. It presents an alternative to classical control methods currently used on the University of Idaho's miniature submarine and underwater crawler. The models of these vehicles are used in training an neural network that optimize the navigation control for the submarine and

Michael Santora; J. Alberts; D. Edwards

2006-01-01

423

532 nm Chaotic Fiber Laser Transmitter for Underwater Lidar.  

National Technical Information Service (NTIS)

This project develops a new optical source for underwater ranging and imaging work. This source is based on an ultra-long cavity infrared fiber laser that generates a chaotic, wide bandwidth, high frequency signal, as is desirable for underwater applicati...

L. K. Rumbaugh

2013-01-01

424

Lobster Eye X-Ray Imaging Underwater Scatterometer.  

National Technical Information Service (NTIS)

The Lobster Eye X-Ray Imaging Underwater Scatterometer (LEXIUS) being developed by Physical Optics Corporation (POC) is an underwater X-ray imager/scatterometer system for high-quality imaging of mines and other objects buried in seabed sediment. The syst...

M. Gertsenshteyn

2005-01-01

425

Automatic installation of underwater elastic structures under unknown currents  

Microsoft Academic Search

This paper deals with the new technique of installation and construction of underwater flexible structures by using learning tracking controller (LTC). The LTC has such potentials on the installation or construction of underwater structures, in deep water under unknown currents, that the structure can be installed precisely on the desired point on seabed. By this method automated construction of very

Hideyuki Suzuki; Qi Tao; Koichiro Yoshida

1998-01-01

426

Effectiveness of underwater devices in the Baltic Sea  

Microsoft Academic Search

The effectiveness and range of ultrasound devices used in underwater investigation and exploration is greatly dependable on spatial distribution of acoustical parameters. Therefore, this problem is usually taken into careful consideration. The aim of the paper is to characterise the possible changes in the range of underwater devices used in conditions typical for the Southern Baltic. The main factor having

Grazyna Grelowska; Eugeniusz Kozaczka

427

Feasibility of Underwater Friction Stir Welding of Hardenable Alloy Steel.  

National Technical Information Service (NTIS)

The objective of this thesis is to determine whether friction stir welding (FSW) is a feasible welding process for steels in an underwater environment. Specific benefits would be underwater weld repairs on steel alloy piping systems and/or structures, and...

N. E. Overfield

2010-01-01

428

Relaxation effects in humans of underwater exercise of moderate intensity.  

PubMed

In this study we investigated the effects of underwater exercise in warm water (34 degrees C) on physiological and psychological relaxation. Eight healthy young men (aged 20-26 years) volunteered for the experiment. The experiment consisted of the following three successive segments: a pre-exercise period of 20 min, during which the subjects rested in a semi-supine posture with their eyes closed for the final 10 min; an underwater exercise period of approximately 60 min, during which the subjects performed gymnastic exercises or aerobic dancing with occasional movements or jumping; a post-exercise recovery of 20 min, which was similar to the pre-exercise rest period. We compared the relative power values (power %) of the electroencephalogram alpha bands (8-13 Hz) and profile of moods states (POMS) before and after the underwater exercise. We also estimated the percentage of maximal heart rate (%HRmax) throughout the experiment to ascertain the intensity of the underwater exercise. The results of %HRmax indicated that the intensity of underwater exercises practised in the experiments ranged from low to moderate. The power % of EEG alpha bands had increased significantly after the underwater exercise compared with the pre-exercise rest (P<0.05). From the POMS results, we observed that positive mood (vigour) increased and negative mood (tension and anxiety, depression and dejection) decreased significantly after the underwater exercise (P<0.05). This study found that the subjects showed increased physiological and psychological indices of relaxation after underwater exercise. PMID:10483793

Oda, S; Matsumoto, T; Nakagawa, K; Moriya, K

1999-09-01

429

A review on motion control of the Underwater Vehicles  

Microsoft Academic Search

Unmanned Underwater Vehicles have gained popularity for the last decades, especially for the purpose of not risking human life in dangerous operations. On the other hand, underwater environment introduces numerous challenges in control, navigation and communication of such vehicles. Certainly, this fact makes the development of these vehicles more interesting and engineering-wise more attractive. In this review study, among the

zgr YILDIZ; R. Blent GKALP; A. Egemen YILMAZ

2009-01-01

430

DMAC: Media access control architecture for underwater acoustic sensor networks  

Microsoft Academic Search

Physical properties of hydroacoustic communication channels differ significantly from those of conventional terrestrial radio channels, the former being characterized by long propaga- tion delays, limited bandwidth, extremely complex and rapidly varying reverberation etc. As an important feature of underwater acoustic modems is the half-duplex nature of communication, development of underwater acoustic sensor networks demands a substantial redesign of algorithms and

Oleksiy Kebkal; Maxim Komar; Konstantin Kebkal; Rudolf Bannasch

2011-01-01

431

Deformation of metal pipe due to underwater shock wave  

Microsoft Academic Search

The deformation process of the metal pipes, accelerated by underwater shock wave resulting from the underwater detonation of explosive inside the metal pipe, was investigated by means of both the optical observation experiment and the numerical calculation. The expanding deformation of metal pipes was experimentally viewed by both framing and streak photographic means. A computer code based on the arbitrary

S. Itoh; A. Kira; Z.-Y. Liu; S. Nagano

1999-01-01

432

A Novel Chirp Slope Keying Modulation Scheme for Underwater Communication  

Microsoft Academic Search

A digital modulation method using Chirp-Slope Keying (CSK) is developed for coherent underwater acoustic communications. Effective signal detection is a critical stage in the implementation of any communications system; we will see that CSK solves some significant challenges to reliable detection. This thesis is primarily based on analyzing the effectiveness of CSK through simulations using Matlab's Simulink for underwater communications.

Lastri Simanjuntak

2004-01-01

433

Multichannel Detection for Wideband Underwater Acoustic CDMA Communications  

Microsoft Academic Search

Direct-sequence (DS) code-division multiple access (CDMA) is considered for future wideband mobile underwater acoustic networks, where a typical configuration may include several autonomous underwater vehicles (AUVs) operating within a few kilometers of a central receiver. Two receivers that utilize multichannel (array) processing of asynchronous multiuser signals are proposed: the symbol decision feedback (SDF) receiver and the chip hypothesis feedback (CHF)

Milica Stojanovic; Lee Freitag

2006-01-01

434

Underwater optical communications systems. Part 2: basic design considerations  

Microsoft Academic Search

Acoustic systems may provide suitable underwater communications because sound propagates well in water. However, the maximum data transmission rates of these systems in shallow littoral waters are ~10 kilobits per second (kbps) which may be achieved only at ranges of less than 100 m. Although underwater (u\\/w) wireless optical communications systems can have even shorter ranges due to greater attenuation

J. W. Giles; I. N. Bankman

2005-01-01

435

Multi-frame restoration of turbulence degraded underwater images  

NASA Astrophysics Data System (ADS)

The ability to image underwater is highly desired for scientific and military applications, including optical communications, situational awareness, diver visibility, and mine detection. However, underwater imaging is severely impaired by scattering and optical turbulence associated with refraction index fluctuations. Naturally, the approaches taken to solve the underwater image restoration problem have their origin in atmospheric turbulence compensation algorithms. There is certain similarity between the atmospheric and underwater image degradations but the difference in the scales of refraction index fluctuations in two media brings out the need for significant modifications of atmospheric techniques to be applicable to underwater imagery. Significantly stronger underwater image distortions resulting in large local shifts and warping of the image features require robust tracking using, for example optical flow estimation, even under relatively benign underwater conditions. Comparative performance of multi-frame nonlinear gain "lucky patch" algorithms with variable degree of optical flow technique sophistication is presented for underwater imagery collected in a laboratory tank and in a field exercise. Reliance of image restoration on accuracy of the optical flow algorithm is revealed and one approach to enhance restored image quality using confidence measures of optical flow estimation is proposed.

Kanaev, Andrey V.

2012-10-01

436

A polarization shift-keying system for underwater optical communications  

Microsoft Academic Search

A compact and simple setup for testing polarization modulation in the underwater channel is demonstrated. The results from this system compare favorably to a non-polarization modulation system utilizing on-off keying modulation. This system will allow future work to explore using polarization in optical communication systems underwater. The advantages of such systems include ability to monitor the water quality of the

William C. Cox; Brian L. Hughes; John F. Muth

2009-01-01

437

Medical Supervision in the Pursuit of Underwater Sports.  

National Technical Information Service (NTIS)

The report contains a review of the development of various aspects of underwater sports in the USSR. Results are cited of a clinico-experimental study of the effect of underwater sport activity on the body and the use of medical safeguards for this sport....

A. A. Askerov V. I. Kronshtadtskii-Karev

1972-01-01

438

Task allocation for networked autonomous underwater vehicles in critical missions  

Microsoft Academic Search

Underwater Acoustic Sensor Networks (UW-ASNs) consist of stationary or mobile nodes such as Autonomous Underwater Vehicles (AUVs), which may be classified as propeller-driven vehicles and gliders, that are equipped with a variety of sensors for performing collaborative monitoring tasks. The missions entrusted to the AUVs in this work are critical to human life and property, are bound by severe time

Indraneel S. Kulkarni; Dario Pompili

2010-01-01

439

Numerical Analysis of Structural Dynamics for Supercavitating Underwater Vehicles  

Microsoft Academic Search

A finite element model for supercavitating underwater vehicles is developed considering the effect of the connection surfaces between cabins on the structural dynamic response. The frequency and transient dynamic analyses are performed, and the performance of supercavitating underwater vehicles with configurations of flanged and sleeve connections is investigated. The numerical results show that the flanged configuration is more reliable than

Ma Zhen-yu; Hu Fan; Lin Ming-dong; Zhang Wei-hua

2010-01-01

440

Operations with Multiple Autonomous Underwater Vehicles: the PISCIS Project  

Microsoft Academic Search

The goals, technical challenges, and activities of the project PISCIS - Multiple Autonomous Underwater Vehicles for Coastal and Environmental Field Studies - are reviewed in the context of the activities of the Underwater Systems and Technologies Laboratory from Porto University. I. I NTRODUCTION The future of humanity is deeply related to the quality of the bodies of water of the

Roberto Frias

441

The entrainment of low frequency breathing periodicity.  

PubMed

It has been predicted by mathematical models of the respiratory control system that the delay between the lung and the respiratory controller may determine the cycle time found in periodic breathing. We examined cycle time of periodic breathing and circulation time in 11 patients known to have circulation delay due to heart failure. We did not find a significant relationship between the amount of periodic breathing and circulation delay, but found a very high correlation between circulation delay and the cycle time of periodic breathing (r2 = 0.825; p = 0.0001). PMID:2225959

Millar, T W; Hanly, P J; Hunt, B; Frais, M; Kryger, M H

1990-11-01

442

How Long Can You Hold Your Breath?  

NSDL National Science Digital Library

In this activity (on page 142 of the PDF), learners will compare breathing rates before and after hyperventilation to explore how reduced carbon dioxide levels in the blood lower the need to breathe. This activity also includes information about how microgravity conditions in space affect sleep and breathing rates of astronauts. This activity can be enhanced by sharing the "Astronaut's Sleep" Podcast with learners (see related resource link). This resource guide includes background information and sample evaluation questions. Note: learners with respiratory ailments, such as asthma or allergies, should not participate in the breath-holding part of this activity.

Macleish, Marlene Y.; Mclean, Bernice R.

2013-05-15

443

[Breath-analysis tests in gastroenetrological diagnosis].  

PubMed

The introduction of a simple method for analysis of 14CO2 in breath allowed a more widely application of breath-tests in the diagnosis of gastroenterological diseases. During a breath-test a 14C-labelled compound is administered orally and 14CO2 is subsequently measured in breath by discontinuous samplings of 14CO2 by virtue of a trapping solution (hyamine hydroxide). Most helpful tests in gastroenterology are the 14C-glycyl-cholate breath test for detecting increased deconjugation of bile acids due to small intestinal bacterial overgrowth or bile acid malabsorption in ileal resection or Crohn's disease of the ileum, the 14C-lactose breath test in lactase deficiency, whereas the 14C-tripalmitin test seems less helpful in the diagnosis of fat malabsorption. A 14C-aminopyrine breath test may turn out to be a simple and valuable liver function test. Oral loading tests with breath analysis of H2 have shown to be helpful in the diagnosis of carbohydrate malabsorption, determination of intestinal transit time and intestinal gas production. Due to technical reasons (gas-chromatographie analysis) H2-breath analysis is still limited to research centers. Despite low radiation doses after oral administration of 14C-labelled compounds oral loading tests with H2- or 13C-analysis might be preferable in the future. PMID:773014

Caspary, W F

1975-12-01

444

Marine Corps Diver's Backpack/Battery Assembly.  

National Technical Information Service (NTIS)

A diver's backpack/battery assembly was developed for the Naval Medical Research Institute for eventual Marine Corps use in shallow water diving. The assembly was a modified MK VIII underwater breathing apparatus backpack with a 28-volt Silvercel battery ...

D. Taylor J. J. Bayles

1969-01-01

445

46 CFR 4.03-1 - Marine casualty or accident.  

Code of Federal Regulations, 2010 CFR

...incident involving significant harm to the environment. (3) Any occurrences of injury or loss of life to any person while diving from a vessel and using underwater breathing apparatus. (4) Any incident described in § 4.05-1(a)....

2012-10-01

446

50 CFR 32.72 - Guam.  

Code of Federal Regulations, 2010 CFR

... 4. We prohibit the collection of corals, giant clams (Tridacna and Hippopus spp.), and coconut crabs (Birgus latro ) on the refuge. 5. We prohibit use of Self Contained Underwater Breathing Apparatus (SCUBA) to take fish...

2009-10-01

447

50 CFR 32.72 - Guam.  

Code of Federal Regulations, 2010 CFR

... 4. We prohibit the collection of corals, giant clams (Tridacna and Hippopus spp.), and coconut crabs (Birgus latro ) on the refuge. 5. We prohibit use of Self Contained Underwater Breathing Apparatus (SCUBA) to take fish...

2010-10-01

448

U S Navy Diving Manual. Volume 2. Mixed-Gas Diving. Revision 1.  

National Technical Information Service (NTIS)

Contents: Mixed-Gas Diving Theory; Operations Planning; Mixed-Gas Underwater Breathing Apparatus; Surface-Supplied Mixed-Gas Diving Operations; Deep Diving Systems; Oxygen Diving Operations; Mixed-Gas Surface-Supplied Decompression; Mixed-Gas Scuba Decomp...

1981-01-01

449

Design and evaluation of a modified underwater cycle ergometer.  

PubMed

An underwater cycle ergometer was designed consisting of an aluminum cycle frame in water connected with a 1:1 gear ratio to a mechanically braked standard cycle ergometer supported above the water. Three progressive maximal exercise tests were performed (n = 10): (a) the underwater ergometer in water (UEW), (b) underwater ergometer in air (UEA), and (c) a standard cycle ergometer in air (SEA). At submaximal power outputs, oxygen consumption (VO2) and heart rate (HR) were generally lower in the SEA condition (p < .05), indicating that exercise in the upright position was more efficient. Exercise in water (UEW) resulted in lower total exercise duration, maximal HR, and maximal Tes than in air conditions. The upright position (SEA) resulted in greater total exercise duration and maximal power output than the semirecumbent positions. Because of positional differences between the standard and underwater ergometers, air-water comparisons should be made by using the underwater ergometer in water and on land. PMID:8727476

Chen, A A; Kenny, G P; Johnston, C E; Giesbrecht, G G

1996-04-01

450

Design and implementation of an underwater sound recording device  

SciTech Connect

The purpose of this study was to design and build two versions of an underwater sound recording device. The device designed is referred to as the Underwater Sound Recorder (USR), which can be connected to one or two hydrophones or other underwater sound sensors. The URS contains a 26 dB preamplifier and a user selectable gain that permits additional amplification of input to the system from 26 dB to 46 dB. Signals within the frequency range up to 15 kHz may be recorded using the USR. Examples of USR applications are monitoring underwater processes that have the potential to create large pressure waves that could potentially harm fish or other aquatic life, such as underwater explosions or pile driving. Additional applications are recording sound generated by vessels or the vocalizations of some marine mammals, such as the calls from many species of whales.

Martinez, Jayson J.; Myers, Joshua R.; Carlson, Thomas J.; Deng, Zhiqun; Rohrer, John S.; Caviggia, Kurt A.

2011-09-19

451

AUTOMATIC COUNTING APPARATUS  

DOEpatents

An apparatus for automatically recording the results of counting operations on trains of electrical pulses is described. The disadvantages of prior devices utilizing the two common methods of obtaining the count rate are overcome by this apparatus; in the case of time controlled operation, the disclosed system automatically records amy information stored by the scaler but not transferred to the printer at the end of the predetermined time controlled operations and, in the case of count controlled operation, provision is made to prevent a weak sample from occupying the apparatus for an excessively long period of time.

Howell, W.D.

1957-08-20

452

Nuclear reactor apparatus  

DOEpatents

A lifting, rotating and sealing apparatus for nuclear reactors utilizing rotating plugs above the nuclear reactor core. This apparatus permits rotation of the plugs to provide under the plug refueling of a nuclear core. It also provides a means by which positive top core holddown can be utilized. Both of these operations are accomplished by means of the apparatus lifting the top core holddown structure off the nuclear core while stationary, and maintaining this structure in its elevated position during plug rotation. During both of these operations, the interface between the rotating member and its supporting member is sealingly maintained.

Wade, Elman E. (Ruffs Dale, PA)

1978-01-01

453

Mirror plasma apparatus  

DOEpatents

A mirror plasma apparatus which utilizes shielding by arc discharge to form a blanket plasma and lithium walls to reduce neutron damage to the wall of the apparatus. An embodiment involves a rotating liquid lithium blanket for a tandem mirror plasma apparatus wherein the first wall of the central mirror cell is made of liquid lithium which is spun with angular velocity great enough to keep the liquid lithium against the first material wall, a blanket plasma preventing the lithium vapor from contaminating the plasma.

Moir, Ralph W. (Livermore, CA)

1981-01-01

454

Breath: A game to motivate the compliance of postoperative breathing exercises  

Microsoft Academic Search

The use of breathing exercises post surgery can reduce pulmonary complications. Incentive spirometry is a widely used device that provides visual feedback for patients during breathing exercises. This paper describes the initial development of an interaction device, game design and initial playtesting and usability of a game to motivate patients to perform post operative breathing exercises.

B. Lange; S. Flynn; A. Rizzo; M. Bolas; M. Silverman; A. Huerta

2009-01-01

455

Shoulder and hip roll differences between breathing and non-breathing conditions in front crawl swimming  

Microsoft Academic Search

The effects of breathing on body roll have been previously investigated for the roll of the whole trunk only. The purposes of this study were: to calculate separately the shoulder roll (SR) and hip roll (HR) of swimmers during front crawl for non-breathing and preferred-side breathing conditions; to assess the differences in the magnitude and temporal characteristics of these variables

Stelios G. Psycharakis; Carla McCabe

2011-01-01

456

Episodic Breathing in Frogs: Converging Hypotheses on Neural Control of Respiration in Air Breathing Vertebrates  

Microsoft Academic Search

SYNOPSIS. The episodic, or intermittent, breathing of frogs and many ecto- thermic vertebrates results in important fluctuations of arterial blood gases. This pattern of breathing differs from the rhythmic and continuous alterna- tion of inspiration observed in most homeotherms, which maintain O2 and CO2 levels within narrow ranges. These differences in pattern of breathing indicate that the respiratory control systems

RICHARD KINKEAD

1997-01-01

457

Breathing resistance of dust respirators  

SciTech Connect

In several of the operations, at Olin Corporation, the use of dust respirators is left to the discretion of the worker since the total solid particulate levels are considerably below the OSHA permissible exposure level. A problem arises when the worker who would use the respirators except: 1) it's hard to breathe through them, 2) the respirators fog our safety glasses, and 3) they are too uncomfortable for eight hours usage when we're doing hard work. The first objection listed above has been preliminarily addressed by a simple test method which measures the pressure drop through the filtering medium of the dust respirator.

Andrew, E.

1985-10-01

458

Optimization of depth control for Unmanned Underwater Vehicle using surrogate modeling technique  

Microsoft Academic Search

The underwater environment poses a difficult challenge for autonomous underwater navigation. A standard problem of underwater vehicles is to maintain its position at a certain depth in order for it to perform desired operations. An effective controller is required for this purpose and hence the design of a depth controller for an Unmanned Underwater Vehicle is described in this paper.

Amrul Faruq; S. S. Abdullah; M. Fauzi; S. Nor

2011-01-01

459

Numerical simulations of motion prediction and manoeuvring rules for underwater vehicles navigating near seabed  

Microsoft Academic Search

The flow field surrounding an underwater vehicle will change due to the influence from seabed terrains, when it navigates near seabed. The hydrodynamic coefficients of the underwater vehicle will change, and then produce a force and pitch moment, which could pull the underwater vehicle to the seabed. So it's very important for the safety of underwater vehicles while navigating near

Du Du; Siming Yuan

2010-01-01

460

An Aquatic Acoustic Metrics Interface Utility for Underwater Sound Monitoring and Analysis  

Microsoft Academic Search

Fishes and other marine mammals suffer a range of potential effects from intense sound sources generated by anthropogenic underwater processes such as pile driving, shipping, sonars, and underwater blasting. Several underwater sound recording devices (USR) were built to monitor the acoustic sound pressure waves generated by those anthropogenic underwater activities, so the relevant processing software becomes indispensable for analyzing the

Huiying Ren; Michele B. Halvorsen; Zhiqun Deng; Thomas J. Carlson

2012-01-01

461

46 CFR 176.650 - Alternative Hull Examination Program options: Divers or underwater ROV.  

Code of Federal Regulations, 2010 CFR

...Examination Program options: Divers or underwater ROV. 176.650 Section 176.650 Shipping...Examination Program options: Divers or underwater ROV. To complete the underwater survey...an underwater remotely operated vehicle (ROV). (a) If you use divers to...

2009-10-01

462

46 CFR 176.650 - Alternative Hull Examination Program options: Divers or underwater ROV.  

Code of Federal Regulations, 2010 CFR

...Examination Program options: Divers or underwater ROV. 176.650 Section 176.650 Shipping...Examination Program options: Divers or underwater ROV. To complete the underwater survey...an underwater remotely operated vehicle (ROV). (a) If you use divers to...

2010-10-01

463

Sample positioning apparatus  

DOEpatents

Apparatus for use in alpha particle counting with such as photomultiplier tubes, comprising a platform and linkage mechanism whereby samples are moved in linear manner toward and away from ends of the photomultiplier tubes.

Bell, Thomas H. (Boulder, CO); Johnson, Jr., Charles H. (Arvada, CO); Lane, Robert L. (Golden, CO); Martin, Bradley E. (Arvada, CO); Tyree, William H. (Boulder, CO)

1976-01-06

464

Doubly Adaptive CFAR Apparatus.  

National Technical Information Service (NTIS)

The doubly adaptive constant false alarm rate (CFAR) apparatus uses a doubly adaptive detector which is based upon the use of an auxiliary parallel adaptive detector in addition to the conventional main adaptive detector. The auxiliary adaptive detector h...

L. G. Cole

1979-01-01

465

Apparatus for forming boreholes  

SciTech Connect

Drilling apparatus is disclosed adapted for drilling upwardly a deviated hole from a carriage assembly disposed in a cased vertical hole below a target zone of a hydrocarbon bearing formation. The drilling apparatus includes a drill motor assembly having a drill bit driven by a shaft of a drill bit mud pressure driven motor. A weight on bit assembly is provided below the drill bit motor for imparting ''weight-on-bit'' drilling force to the drilling bit against the face of the borehole. The weight on bit assembly includes an anti-rotation assembly for preventing rotation of the drill bit motor with respect to the borehole and an axial drive assembly for applying axial force to the drill bit. Apparatus is provided to reverse the direction of the axial force generated by the weight on bit assembly. Apparatus is also provided to limit the axial force applied to the drill bit to a predetermined level.

Burton, J. A.

1985-11-26

466

Vacuum Filtration Apparatus.  

National Technical Information Service (NTIS)

The invention discusses a filtration apparatus which provides for semiautomatic operation by including a filter element dispenser located at a filtration station. In order to effect removal of a used filter element from the filtration station, a tilting m...

R. Repaske A. H. Rich J. L. Slemp

1991-01-01

467

Riser position indication apparatus  

SciTech Connect

This patent describes a Riser Position Indication Apparatus for disposition between an offshore vessel and a riser, the riser being moveable with respect to the offshore vessel. The riser position indication apparatus comprises: vessel connection means operatively engaged with the vessel to secure the riser position indication apparatus to the vessel, riser connection means operatively engaged with the riser to secure the riser position indication apparatus to the riser, flexible weight means having one end connected to one of the connection means and the other end operatively engaged with the other of the connection means, weight signal transmitter means associated with at least one end of the flexible weight means and operative to produce a continuous output signal which varies as a function of the weight of the weight means suspended from one end of the connection means.

Moore, B.B.

1986-09-23

468

Chemiluminescent Marker Apparatus.  

National Technical Information Service (NTIS)

The patent application relates to a chemiluminescent lighting apparatus for generating an illuminated marker material for delivery to a desired area. Two fluids to be mixed are contained in separate chambers and are separated from a mixing chamber by mean...

R. L. Gerber

1974-01-01

469

Energy Efficient Cooperation in Underwater Sensor Networks  

Microsoft Academic Search

Energy efficient communication is a key requirement\\u000d\\u000aof energy-constrained underwater sensor networks (UWSNs). In\\u000d\\u000athis paper, we show that the cooperative diversity, which is\\u000d\\u000aconventionally utilized to improve reliability in UWSNs, can be\\u000d\\u000aemployed to reduce energy consumption and preserve a reasonable\\u000d\\u000alevel of data reliability and communication delay. We first\\u000d\\u000aelucidate in what circumstances the cooperative diversity saves\\u000d\\u000aenergy

Hongkun Yang; Fengyuan Ren; Chuang Lin; Bin Liu

2010-01-01

470

Underwater sunlight maxima in the Menai Strait  

NASA Astrophysics Data System (ADS)

In a tidal sea, the time variation of underwater daylight depends on the rise and fall of the tide as well as the motion of the sun across the sky. If conditions are right, more than one maximum in underwater daylight can occur in a single day. In this paper we apply a simple analytical solution for the number of maxima and their timing to observations in the Menai Strait in Europe. The number of maxima depends on the value of the parameter ggr = kRohgr2q2 where k is the diffuse attenuation coefficient, R is the tidal range, ohgr the angular frequency of the tide and q is a factor proportional to the day length. If the value of ggr is greater than a critical value, and the day is long enough, then a double maximum in underwater sunlight is formed. The maxima lie between noon and low water, and their time relative to noon is given by tL = ggr/(ggr+4) where tL is the time of low water relative to noon. The critical value of ggr varies from 4 to about 18, depending on the time of high water. The necessary length of day to produce the double maximum depends on the time of low water relative to noon, the required condition being |tL|<3q/2+6q/ggr, where tL is the time of low water in hours relative to noon. The observations reported here are in agreement with these predictions. In the high tidal ranges of the Menai Strait, ggr exceeds the critical value for about half the spring-neap cycles in summer, and the daily pattern of illumination switches from a double peaked to a single peaked curve. Maxima occur as early as 6 am and as late as 7 pm. Over this complete range, the times of the observed maxima are close to those predicted, the rms difference between times of observed and predicted maxima is about 45 min and the mean difference is less than 10 min. We conclude that the analytical theory presented here is a useful practical tool for predicting maxima in underwater sunlight in a tidal sea.

Bowers, D. G.; Brubaker, J. M.

2004-07-01

471

Covert underwater acoustic communication using dolphin sounds.  

PubMed

In November 2012, an experiment demonstrating biological mimicry method for covert underwater acoustic communication (UAC) was conducted at Lianhua Lake in Heilongjiang China. Dolphin whistles were used for synchronization while dolphin clicks were used as information carrier. The time interval between dolphin clicks conveys the information bits. Channel estimates were obtained with matching pursuit (MP) algorithm, which is useful for sparse channel estimation. Adaptive RAKE Equalization was employed at the receiver. Bit error rates were less than 10(-4) with 37 bits per second data rate in the lake trial. PMID:23556695

Liu, Songzuo; Qiao, Gang; Ismail, Asim

2013-04-01

472

Science 101: How do animals communicate underwater?  

NSDL National Science Digital Library

Well, they often use hand signals, such as the "OK" sign, and sometimes they write on message boards. So much for how SCUBA divers (classified as animals) communicate! Other than the authors' knowledge of sound waves and how they move air and water, along with the fact that whales and dolphins make cool sounds, SCUBA diver communication was about the extent of his understanding of how animals' communicate underwater. So, he did a bit of research and discovered lots of interesting things, which he shares in this month's column.

Robertson, William C.

2008-04-01

473

Cardiac changes induced by immersion and breath-hold diving in humans.  

PubMed

To evaluate the separate cardiovascular response to body immersion and increased environmental pressure during diving, 12 healthy male subjects (mean age 35.2 +/- 6.5 yr) underwent two-dimensional Doppler echocardiography in five different conditions: out of water (basal); head-out immersion while breathing (condition A); fully immersed at the surface while breathing (condition B) and breath holding (condition C); and breath-hold diving at 5-m depth (condition D). Heart rate, left ventricular volumes, stroke volume, and cardiac output were obtained by underwater echocardiography. Early (E) and late (A) transmitral flow velocities, their ratio (E/A), and deceleration time of E (DTE) were also obtained from pulsed-wave Doppler, as left ventricular diastolic function indexes. The experimental protocol induced significant reductions in left ventricular volumes, left ventricular stroke volume (P < 0.05), cardiac output (P < 0.001), and heart rate (P < 0.05). A significant increase in E peak (P < 0.01) and E/A (P < 0.01) and a significant reduction of DTE (P < 0.01) were also observed. Changes occurring during diving (condition D) accounted for most of the changes observed in the experimental series. In particular, cardiac output at condition D was significantly lower compared with each of the other experimental conditions, E/A was significantly higher during condition D than in conditions A and C. Finally, DTE was significantly shorter at condition D than in basal and condition C. This study confirms a reduction of cardiac output in diving humans. Since most of the changes were observed during diving, the increased environmental pressure seems responsible for this hemodynamic rearrangement. Left ventricular diastolic function changes suggest a constrictive effect on the heart, possibly accounting for cardiac output reduction. PMID:18467547

Marabotti, Claudio; Scalzini, Alessandro; Cialoni, Danilo; Passera, Mirko; L'Abbate, Antonio; Bedini, Remo

2008-05-08

474

14 CFR 29.1439 - Protective breathing equipment.  

Code of Federal Regulations, 2013 CFR

... 2013-01-01 false Protective breathing equipment. 29.1439 Section 29...Equipment § 29.1439 Protective breathing equipment. (a) If one or more...to be accessible in flight, protective breathing equipment must be available for an...

2013-01-01

475

Vacuum pump apparatus  

DOEpatents

An improved cryopumping apparatus which comprises a cryopumping space which may be alternately opened and closed from the surrounding area by moveable panels, trubular cryopanels within said cryopumping space through which a coolant such as liquid helium may be passed, and an apparatus for spraying liquid argon onto said cylindrical cryopanels in order to enhance the cryogenic entrapment of such low-z ions, atoms, and molecules as hydrogen and helium.

Batzer, Thomas H. (Livermore, CA); Call, Wayne R. (Tracy, CA)

1985-01-01

476

Fiber pulling apparatus modification  

NASA Astrophysics Data System (ADS)

A reduced gravity fiber pulling apparatus (FPA) was constructed in order to study the effects of gravity on glass fiber formation. The apparatus was specifically designed and built for use on NASA's KC-135 aircraft. Four flights have been completed to date during which E-glass fiber was successfully produced in simulated zero, high, and lunar gravity environments. In addition simulated lunar soil samples were tested for their fiber producing properties using the FPA.

Smith, Guy A.; Workman, Gary L.

1992-11-01

477

Spin coating apparatus  

DOEpatents

A spin coating apparatus requires less cleanroom air flow than prior spin coating apparatus to minimize cleanroom contamination. A shaped exhaust duct from the spin coater maintains process quality while requiring reduced cleanroom air flow. The exhaust duct can decrease in cross section as it extends from the wafer, minimizing eddy formation. The exhaust duct can conform to entrainment streamlines to minimize eddy formation and reduce interprocess contamination at minimal cleanroom air flow rates.

Torczynski, John R. (Albuquerque, NM)

2000-01-01

478

Electric arc saw apparatus  

DOEpatents

A portable, hand-held electric arc saw apparatus comprising a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc between the blade and a workpiece of opposite polarity. Electrically conducting means are provided on said frame for transmitting current to said blade. A pair of freely movable endless belts in the form of crawler treads are employed to facilitate movement of the apparatus relative to the workpiece.

Deichelbohrer, P.R.

1983-08-08

479

Line retrieving apparatus  

US Patent & Trademark Office Database

An apparatus and method for retrieving lines, ropes, wires, optical fibres and the like from otherwise inaccessable locations, without the need for separate control lines, dissolving tables and the like. The apparatus comprises a line guide assembly, line clamping assembly, a line cutting assembly and a triggering mechanism for the activation of the aforementioned assemblies. The triggering mechanism is activated by the application of force to the line to be retrieved.

Orlick; Jonathan B. (Fort Worth, TX); Howard; William H. (Irvine, CA)

1990-03-20

480

Hemoptysis and pneumomediastinum after breath-hold diving in shallow water: a case report.  

PubMed

We report the case of a healthy 21-year-old woman who performed iterative breath-hold dives in relatively cold water, not exceeding depths of 5 meters but with "empty lungs." At the end of a dive, after experiencing an intense involuntary diaphragmatic contraction underwater, she presented hemoptysis followed by chest pain and cough. Chest radiography and computed tomography were performed 24 hours later, confirming the diagnosis of pneumomediastinum. The clinical course was benign: However, chest pain and effort dyspnea lasted for a few weeks. The pathophysiology of this accident may be explained by a combination of mechanisms involved in several clinical entities, namely pulmonary edema of immersion, pulmonary barotrauma and spontaneous pneumomediastinum. PMID:21721355

Henckes, A; Arvieux, J; Cochard, G; Jzquel, P; Arvieux, C C

481

EXHALED BREATH ANALYSIS FOR HUMAN EXPOSURE RESEARCH  

EPA Science Inventory

Exhaled breath collection and analysis has historically been used in environmental research studies to characterize exposures to volatile organic compounds. The use of this approach is based on the fact that many compounds present in blood are reflected in the breath, and that...

482

News from the Breath Analysis Summit 2011  

Microsoft Academic Search

This special section highlights some of the important work presented at the Breath Analysis Summit 2011, which was held in Parma (Italy) from 11 to 14 September 2011. The meeting, which was jointly organized by the International Association for Breath Research and the University of Parma, was attended by more than 250 delegates from 33 countries, and offered 34 invited

Massimo Corradi; Antonio Mutti

2012-01-01

483

Pain and faulty breathing: a pilot study  

Microsoft Academic Search

The purpose of this pilot study was to observe both relaxed and deep breathing patterns in a convenience sample to determine the incidence of normal versus faulty patterns of respiration. These observations were then combined with respondent answers to a survey on pain history to determine if there is any correlation between faulty breathing and musculo-skeletal pain patterns. If such

Maria A. Perri; Elizabeth Halford

2004-01-01

484

Breath testing and highway fatality rates  

Microsoft Academic Search

This paper presents an empirical investigation of the effect of a preliminary breath test law on highway fatality rates. A preliminary breath test law reduces the procedural problems associated with obtaining evidence of drunk driving and thus increases the probability that a drunk driver will be arrested. According to the theory of deterrence, increasing the probability of arrest for drunk

Henry Saffer; Frank Chaloupka

1989-01-01

485

Evidence for Cancer Biomarkers in Exhaled Breath  

Microsoft Academic Search

A Review: Cancer cell growth releases molecular biomarkers into blood that can be useful in diagnostic tests, e.g., serum biomarkers. The use of serum biomarkers involves an invasive sample collection procedure. Human exhaled breath is potentially a noninvasive source of cancer biomarker compounds. A few breath analysis studies have reported sensitivities > 90% and specificities > 80% using a suite

Jan E. Szulejko; Michael McCulloch; Jennifer Jackson; Dwight L. McKee; Jim C. Walker; Touradj Solouki

2010-01-01

486

How Does a Hopping Kangaroo Breathe?  

ERIC Educational Resources Information Center

|We developed a model to demonstrate how a hopping kangaroo breathes. Interestingly, a kangaroo uses less energy to breathe while hopping than while standing still. This occurs, in part, because rather than using muscle power to move air into and out of the lungs, air is pulled into (inspiration) and pushed out of (expiration) the lungs as the

Giuliodori, Mauricio J.; Lujan, Heidi L.; Janbaih, Hussein; DiCarlo, Stephen E.

2010-01-01

487

What is Normal Breath? Challenge and Opportunity  

Microsoft Academic Search

HE current resurgence in the interest of breath analysis is a reflection of advances in analytical chemistry instrumentation. For despite terrific promise of breath analysis and the fact that there have been literally thousands of publications published during the last one hundred years, only a handful of breathtestsareusedclinicallyandafewothersusedforresearch purposes.

Steven F. Solga; Terence H. Risby

2010-01-01

488

DNA-Coated Nanosensors for Breath Analysis  

Microsoft Academic Search

The analysis of breath and body odors can provide valuable information relevant to disease detection, diagnosis and treatment. A variety of technical developments are being pursued to develop electronic devices intended to analyze volatile components of breath and body odors with the sensitivity, selectivity, and learning ability of high-end mammalian olfactory systems. Here, we describe a new sensor technology that

A. T. Charlie Johnson; Samuel M. Khamis; George Preti; Jae Kwak; Alan Gelperin

2010-01-01

489

Breathing Feedback System with Wearable Textile Sensors  

Microsoft Academic Search

Breathing exercises form an essential part of the treatment for respiratory illnesses such as cystic fibrosis. Ideally these exercises should be performed on a daily basis. This paper presents an interactive system using a wearable textile sensor to monitor breathing patterns. A graphical user interface provides visual real-time feedback to patients. The aim of the system is to encourage the

Edmond Mitchell; Shirley Coyle; N. E. O'Connor; D. Diamond; T. Ward

2010-01-01

490

Measuring Your Breathing Frequency at Rest  

NSDL National Science Digital Library

In this activity about the brain and sleep (on page 138 of the PDF), learners measure their resting breathing rates. Learners will discover that breathing frequencies vary amongst individuals. This activity can be enhanced by sharing the "Astronaut's Sleep" Podcast with learners (see related resource link). This resource guide includes background information and sample evaluation questions.

Macleish, Marlene Y.; Mclean, Bernice R.

2013-05-15

491

The effect of breath freshener strips on two types of breath alcohol testing instruments.  

PubMed

The potential for breath freshener strips to interfere with the accuracy of a breath alcohol test was studied. Twelve varieties of breath freshener strips from five manufacturers were examined. Breath tests were conducted using the infrared based BAC DataMaster or the fuel cell based Alco-Sensor IV-XL, 30 and 150 seconds after placing a breath strip on the tongue. No effect was observed using the Alco-Sensor system. Some of the strips gave a small reading at 30 seconds (less than or equal to 0.010 g/210 L apparent alcohol) using the DataMaster. Readings on the DataMaster returned to zero by the 150 second test. A proper pre-test observation and deprivation period should prevent any interference from breath freshener strips on breath alcohol testing. PMID:15317204

Moore, Ronald L; Guillen, Jennifer

2004-07-01

492

Changes in P300 following alternate nostril yoga breathing and breath awareness  

PubMed Central

This study assessed the effect of alternate nostril yoga breathing (nadisuddhi pranayama) on P300 auditory evoked potentials compared to a session of breath awareness of equal duration, in 20 male adult volunteers who had an experience of yoga breathing practices for more than three months. Peak amplitudes and peak latencies of the P300 were assessed before and after the respective sessions. There was a significant increase in the P300 peak amplitudes at Fz, Cz, and Pz and a significant decrease in the peak latency at Fz alone following alternate nostril yoga breathing. Following breath awareness there was a significant increase in the peak amplitude of P300 at Cz. This suggests that alternate nostril yoga breathing positively influences cognitive processes which are required for sustained attention at different scalp sites (frontal, vertex and parietal), whereas breath awareness brings about changes at the vertex alone.

2013-01-01

493

Effects of depth and chest volume on cardiac function during breath-hold diving.  

PubMed

Cardiac response to breath-hold diving in human beings is primarily characterized by the reduction of both heart rate and stroke volume. By underwater Doppler-echocardiography we observed a "restrictive/constrictive" left ventricular filling pattern compatible with the idea of chest squeeze and heart compression during diving. We hypothesized that underwater re-expansion of the chest would release heart constriction and normalize cardiac function. To this aim, 10 healthy male subjects (age 34.2 +/- 10.4) were evaluated by Doppler-echocardiography during breath-hold immersion at a depth of 10 m, before and after a single maximal inspiration from a SCUBA device. During the same session, all subjects were also studied at surface (full-body immersion) and at 5-m depth in order to better characterize the relationship of echo-Doppler pattern with depth. In comparison to surface immersion, 5-m deep diving was sufficient to reduce cardiac output (P = 0.042) and increase transmitral E-peak velocity (P < 0.001). These changes remained unaltered at a 10-m depth. Chest expansion at 10 m decreased left ventricular end-systolic volume (P = 0.024) and increased left ventricular stroke volume (P = 0.024). In addition, it decreased transmitral E-peak velocity (P = 0.012) and increased deceleration time of E-peak (P = 0.021). In conclusion the diving response, already evident during shallow diving (5 m) did not progress during deeper dives (10 m). The rapid improvement in systolic and diastolic function observed after lung volume expansion is congruous with the idea of a constrictive effect on the heart exerted by chest squeeze. PMID:19424715

Marabotti, Claudio; Scalzini, Alessandro; Cialoni, Danilo; Passera, Mirko; Ripoli, Andrea; L'Abbate, Antonio; Bedini, Remo

2009-05-08

494

Range Imaging for Underwater Vision Enhancement  

SciTech Connect

This paper presents results from a series of preliminary tests to evaluate a scannerless range-imaging device as a potential sensory enhancement tool for divers and as a potential identification sensor for deployment on small unmanned underwater vehicles. The device, developed by Sandia National Laboratories, forms an image on the basis of point-to-point range to the target rather than an intensity map. The range image is constructed through a classical continuous wave phase detection technique in which the light source is amplitude modulated at radio frequencies. The receiver incorporates a gain-modulated image intensifier, and range information is calculated on the basis of the phase difference between the transmitted and reflected signal. The initial feasibility test at the Coastal Systems Station showed the device to be effective at imaging low-contrast underwater targets such as concertina wire. It also demonstrated success at imaging a 21-inch sphere at a depth of 10 feet in the water column through a wavy air-water interface.

Rish, J.W.; Blume, B.; Nellums, B.; Sackos, J.; Foster, J.; Wood, J.L.

1999-04-19

495

Last Progress in Underwater Electrical Wire Explosion  

NASA Astrophysics Data System (ADS)

The results of the investigation of the underwater electrical wire explosions using a high power nanosecond timescale generator are reported. The spectroscopic analysis of the emitted radiation has unveiled no evidence for the formation of shunting plasma channel. The latter appears in vacuum and gas wire explosions and causes to the seizure of energy deposition into an exploding wire material. The combination of mechanism for the suppression of formation of shunting channel together with the increased energy deposition rate allow busting the efficiency of energy deposition into the exploding wire. Estimated energy deposition into Cu and Al wire material of up to 200 eV/atom was reported. Careful analysis of the generated shock waves show, that 15 % of the deposited energy is transferred into the mechanical energy of the produced water flow. In addition experiments with converging shock waves produced by underwater explosion of cylindrical wire arrays demonstrated the possibility of producing shock waves with pressure amplitude up to 0.25 Mbar at 0.1 mm distance from the axis of the implosion.

Grinenko, Alon; Sayapin, Arkady; Efimov, Sergey; Fedotov, Alexander; Krasik, Yakov E.

496

Impacts of optical turbulence on underwater imaging  

NASA Astrophysics Data System (ADS)

Optical signal transmission underwater is of vital interests to both civilian and military applications. The range and signal to noise during the transmission, as a function of system and water optical properties determines the effectiveness of EO technology. These applications include diver visibility, search and rescue, mine detection and identification, and optical communications. The impact of optical turbulence on underwater imaging has been postulated and observed by many researchers. However, no quantative studies have been done until recently, in terms of both the environmental conditions, and impacts on image quality as a function of range and spatial frequencies. Image data collected from field measurements during SOTEX (Skaneateles Optical Turbulence Exercise, July 22-31, 2010) using the Image Measurement Assembly for Subsurface Turbulence (IMAST) are presented. Optical properties of the water column in the field were measured using WETLab's ac-9 and Laser In Situ Scattering and Transmissometer (LISST, Sequoia Scientific), in coordination with physical properties including CTD (Seabird), dissipation rate of kinetic energy and heat, using both the Vector velocimeter and CT combo (Nortek and PME), and shear probe based Vertical Microstructure Profiler (VMP, Rockland). The strong stratification structure in the water column provides great opportunity to observe various dissipation strengths throughout the water column, which corresponds directly with image quality as shown. Initial results demonstrate general agreement between data collected and model prediction, while discrepancies between measurements and model suggest higher spatial and temporal observations are needed in the future.

Hou, Weilin; Woods, S.; Goode, W.; Jarosz, E.; Weidemann, A.

2011-05-01

497

Features of underwater acoustics from Aristotle to our time  

NASA Astrophysics Data System (ADS)

Underwater acoustics has been one of the fastest growing fields of research in acoustics. In particular, the 20th Century has taken our understanding of underwater acoustics phenomena a great step forward. The two World Wars contributed to the recognition of the importance of research in underwater acoustics, and the momentum in research and development gained during World War II did not reduce in the years after the war. The so-called cold war and the development in computer technology both contributed substantially to the development in underwater acoustics over the second half of the 20th Century. However, the very widespread field of underwater acoustic activities started nearly 2300 years ago with human curiosity about the fundamental nature of sound in the sea. From primitive philosophical and experimental studies of the velocity of sound in the sea and through centuries of successes and failures, the knowledge about underwater acoustics has developed into its high-technological status of today. In particular the development through the period from Aristotle (384 322 BC) to 1960 formed the basis for the tremendous research and development efforts we have witnessed in our time. In this paper most emphasis will be put on the development in underwater acoustics through this period of nearly 2300 years duration, and only the main trends in later research will be mentioned.

Bjrn, Leif

2003-01-01

498

Sleep disordered breathing in children.  

PubMed

Sleep disordered breathing (SDB) is increasingly being recognised as a cause of morbidity even in young children. With an estimated prevalence of 1 to 4 per cent, SDB results from having a structurally narrow airway combined with reduced neuromuscular tone and increased airway collapsibility. SDB in children differs from adults in a number of ways, including presenting symptoms and treatment. Presentation may differ according to the age of the child. Children have a more varied presentation from snoring and frequent arousals to enuresis to hyperactivity. Those with Down syndrome, midface hypoplasia or neuromuscular disorders are at higher risk for developing SDB. First line definitive treatment in children involves tonsillectomy and adenoidectomy. Rapid maxillary expansion, allergy treatment and continuous positive airway pressure (CPAP) are other options. As untreated SDB results in complications as learning difficulties, memory loss and a long term increase in risk of hypertension, depression and poor growth, it is important to diagnose SDB. PMID:20308756

Sinha, Deepti; Guilleminault, Christian

2010-02-01

499

A secure communication suite for underwater acoustic sensor networks.  

PubMed

In this paper we describe a security suite for Underwater Acoustic Sensor Networks comprising both fixed and mobile nodes. The security suite is composed of a secure routing protocol and a set of cryptographic primitives aimed at protecting the confidentiality and the integrity of underwater communication while taking into account the unique characteristics and constraints of the acoustic channel. By means of experiments and simulations based on real data, we show that the suite is suitable for an underwater networking environment as it introduces limited, and sometimes negligible, communication and power consumption overhead. PMID:23202204

Dini, Gianluca; Lo Duca, Angelica

2012-11-07

500

A Secure Communication Suite for Underwater Acoustic Sensor Networks  

PubMed Central

In this paper we describe a security suite for Underwater Acoustic Sensor Networks comprising both fixed and mobile nodes. The security suite is composed of a secure routing protocol and a set of cryptographic primitives aimed at protecting the confidentiality and the integrity of underwater communication while taking into account the unique characteristics and constraints of the acoustic channel. By means of experiments and simulations based on real data, we show that the suite is suitable for an underwater networking environment as it introduces limited, and sometimes negligible, communication and power consumption overhead.

Dini, Gianluca; Duca, Angelica Lo

2012-01-01