Investigating Autonomic Control of the Cardiovascular System: A Battery of Simple Tests

ERIC Educational Resources Information Center

Johnson, Christopher D.; Roe, Sean; Tansey, Etain A.

2013-01-01

Sympathetic and parasympathetic divisions of the autonomic nervous system constantly control the heart (sympathetic and parasympathetic divisions) and blood vessels (predominantly the sympathetic division) to maintain appropriate blood pressure and organ blood flow over sometimes widely varying conditions. This can be adversely affected by…

Automated Power-Distribution System

NASA Technical Reports Server (NTRS)

Ashworth, Barry; Riedesel, Joel; Myers, Chris; Miller, William; Jones, Ellen F.; Freeman, Kenneth; Walsh, Richard; Walls, Bryan K.; Weeks, David J.; Bechtel, Robert T.

1992-01-01

Autonomous power-distribution system includes power-control equipment and automation equipment. System automatically schedules connection of power to loads and reconfigures itself when it detects fault. Potential terrestrial applications include optimization of consumption of power in homes, power supplies for autonomous land vehicles and vessels, and power supplies for automated industrial processes.

Development of technology for creating intelligent control systems for power plants and propulsion systems for marine robotic systems

NASA Astrophysics Data System (ADS)

Iakovleva, E. V.; Momot, B. A.

2017-10-01

The object of this study is to develop a power plant and an electric propulsion control system for autonomous remotely controlled vessels. The tasks of the study are as follows: to assess remotely controlled vessels usage reasonability, to define the requirements for this type of vessel navigation. In addition, the paper presents the analysis of technical diagnostics systems. The developed electric propulsion control systems for vessels should provide improved reliability and efficiency of the propulsion complex to ensure the profitability of remotely controlled vessels.

Control Architecture for Robotic Agent Command and Sensing

NASA Technical Reports Server (NTRS)

Huntsberger, Terrance; Aghazarian, Hrand; Estlin, Tara; Gaines, Daniel

2008-01-01

Control Architecture for Robotic Agent Command and Sensing (CARACaS) is a recent product of a continuing effort to develop architectures for controlling either a single autonomous robotic vehicle or multiple cooperating but otherwise autonomous robotic vehicles. CARACaS is potentially applicable to diverse robotic systems that could include aircraft, spacecraft, ground vehicles, surface water vessels, and/or underwater vessels. CARACaS incudes an integral combination of three coupled agents: a dynamic planning engine, a behavior engine, and a perception engine. The perception and dynamic planning en - gines are also coupled with a memory in the form of a world model. CARACaS is intended to satisfy the need for two major capabilities essential for proper functioning of an autonomous robotic system: a capability for deterministic reaction to unanticipated occurrences and a capability for re-planning in the face of changing goals, conditions, or resources. The behavior engine incorporates the multi-agent control architecture, called CAMPOUT, described in An Architecture for Controlling Multiple Robots (NPO-30345), NASA Tech Briefs, Vol. 28, No. 11 (November 2004), page 65. CAMPOUT is used to develop behavior-composition and -coordination mechanisms. Real-time process algebra operators are used to compose a behavior network for any given mission scenario. These operators afford a capability for producing a formally correct kernel of behaviors that guarantee predictable performance. By use of a method based on multi-objective decision theory (MODT), recommendations from multiple behaviors are combined to form a set of control actions that represents their consensus. In this approach, all behaviors contribute simultaneously to the control of the robotic system in a cooperative rather than a competitive manner. This approach guarantees a solution that is good enough with respect to resolution of complex, possibly conflicting goals within the constraints of the mission to be accomplished by the vehicle(s).

Concept design and hydrodynamic optimization of an innovative SWATH USV by CFD methods

NASA Astrophysics Data System (ADS)

Brizzolara, Stefano; Curtin, Tom; Bovio, Marco; Vernengo, Giuliano

2012-02-01

The paper presents the main characteristics of an innovative platform which has been conceived and designed to extend the operational capabilities of current unmanned surface vehicles in terms of platform stability in waves and of powering requirement at a relatively high speed. The main idea which rules the project is the realization of a small autonomous surface unit (about 6 m in length) capable of undertaking several tasks in the marine environment even with moderate rough sea conditions. The designed vessel has the ability to locate, recover, and launch other members of the autonomous fleet (like AUVs or other underwater devices) and at the same time could carry out a surveillance service of the surrounding areas. To manage these tasks, the vehicle is designed to provide a fairly good autonomy which is needed to face intermediate-range missions (100 nautical miles). The choice of a small waterplane area twin hull (SWATH) form has been motivated by its excellent properties of seakeeping qualities, combined with a non-conventional low resistance underwater hull shape, currently under patenting process, which is able to reduce to a minimum the resistance of the vessel especially at higher speeds. To obtain the most efficient profile of the underwater bodies, a systematic optimization with an automatic procedure based on a parametric definition of the geometry, a state-of-the-art computational fluid dynamics (CFD) flow solver, and a differential evolution global minimization algorithm have been created and used. As expected, all the final CFD computations on the best design have demonstrated the superior efficiency of the developed unconventional SWATH technology with respect to different alternatives of current hull typologies.

Autonomic control of the eye

PubMed Central

McDougal, David H.; Gamlin, Paul D.

2016-01-01

The autonomic nervous system influences numerous ocular functions. It does this by way of parasympathetic innervation from postganglionic fibers that originate from neurons in the ciliary and pterygopalatine ganglia, and by way of sympathetic innervation from postganglionic fibers that originate from neurons in the superior cervical ganglion. Ciliary ganglion neurons project to the ciliary body and the sphincter pupillae muscle of the iris to control ocular accommodation and pupil constriction, respectively. Superior cervical ganglion neurons project to the dilator pupillae muscle of the iris to control pupil dilation. Ocular blood flow is controlled both via direct autonomic influences on the vasculature of the optic nerve, choroid, ciliary body, and iris, as well as via indirect influences on retinal blood flow. In mammals, this vasculature is innervated by vasodilatory fibers from the pterygopalatine ganglion, and by vasoconstrictive fibers from the superior cervical ganglion. Intraocular pressure is regulated primarily through the balance of aqueous humor formation and outflow. Autonomic regulation of ciliary body blood vessels and the ciliary epithelium is an important determinant of aqueous humor formation; autonomic regulation of the trabecular meshwork and episcleral blood vessels is an important determinant of aqueous humor outflow. These tissues are all innervated by fibers from the pterygopalatine and superior cervical ganglia. In addition to these classical autonomic pathways, trigeminal sensory fibers exert local, intrinsic influences on many of these regions of the eye, as well as on some neurons within the ciliary and pterygopalatine ganglia. PMID:25589275

Networking Multiple Autonomous Air and Ocean Vehicles for Oceanographic Research and Monitoring

NASA Astrophysics Data System (ADS)

McGillivary, P. A.; Borges de Sousa, J.; Rajan, K.

2013-12-01

Autonomous underwater and surface vessels (AUVs and ASVs) are coming into wider use as components of oceanographic research, including ocean observing systems. Unmanned airborne vehicles (UAVs) are now available at modest cost, allowing multiple UAVs to be deployed with multiple AUVs and ASVs. For optimal use good communication and coordination among vehicles is essential. We report on the use of multiple AUVs networked in communication with multiple UAVs. The UAVs are augmented by inferential reasoning software developed at MBARI that allows UAVs to recognize oceanographic fronts and change their navigation and control. This in turn allows UAVs to automatically to map frontal features, as well as to direct AUVs and ASVs to proceed to such features and conduct sampling via onboard sensors to provide validation for airborne mapping. ASVs can also act as data nodes for communication between UAVs and AUVs, as well as collecting data from onboard sensors, while AUVs can sample the water column vertically. This allows more accurate estimation of phytoplankton biomass and productivity, and can be used in conjunction with UAV sampling to determine air-sea flux of gases (e.g. CO2, CH4, DMS) affecting carbon budgets and atmospheric composition. In particular we describe tests in July 2013 conducted off Sesimbra, Portugal in conjunction with the Portuguese Navy by the University of Porto and MBARI with the goal of tracking large fish in the upper water column with coordinated air/surface/underwater measurements. A thermal gradient was observed in the infrared by a low flying UAV, which was used to dispatch an AUV to obtain ground truth to demonstrate the event-response capabilities using such autonomous platforms. Additional field studies in the future will facilitate integration of multiple unmanned systems into research vessel operations. The strength of hardware and software tools described in this study is to permit fundamental oceanographic measurements of both ocean and atmosphere over temporal and spatial scales that have previously been problematic. The methods demonstrated are particularly suited to the study of oceanographic fronts and for tracking and mapping oil spills or plankton blooms. With the networked coordination of multiple autonomous systems, individual components may be changed out while ocean observations continue, allowing coarse to fine spatial studies of hydrographic features over temporal dimensions that would otherwise be difficult, including diurnal and tidal periods. Constraints on these methods currently involve coordination of data archiving systems into shipboard operating systems, familiarization of oceanographers with these methods, and existing nearshore airspace use constraints on UAVs. An important outcome of these efforts is to understand the methodology for using multiple heterogeneous autonomous vehicles for targeted science exploration.

Recent UAS Developments: VTOL HQ-series Shipboard Recovery and Autonomous Monitoring with MicroQuads

NASA Astrophysics Data System (ADS)

Wardell, L. J.; Farber, A. M.; Douglas, J.

2017-12-01

Ocean research would benefit from reliable shipboard launch and recovery of small class UAS. The vertical take-off and landing (VTOL) system reduces equipment footprint without the need for launchers or recovery systems. The HQ-60 (Latitude Engineering) has demonstrated reliable ship take-off and recovery on a 10x10' area on the R/V Falkor (Schmidt Ocean Institute) and other research vessels. The HQ-60 recently set a record for longest time aloft for a VTOL aircraft, flying nearly 22.5 hours non-stop. To support close-range research, autonomous MicroQuads that "perch" in a protective box that also recharges the aircraft and transmits the data is in development. Recent MicroQuad work with developing high-resolution (<1cm) DEMs using on-board cameras has yielded promising results for the use of surface change detection. Recent USDA development targeted erosion monitoring with this system. The latest updates and testing results for both systems will be presented.

Autonomous sensor particle for parameter tracking in large vessels

NASA Astrophysics Data System (ADS)

Thiele, Sebastian; Da Silva, Marco Jose; Hampel, Uwe

2010-08-01

A self-powered and neutrally buoyant sensor particle has been developed for the long-term measurement of spatially distributed process parameters in the chemically harsh environments of large vessels. One intended application is the measurement of flow parameters in stirred fermentation biogas reactors. The prototype sensor particle is a robust and neutrally buoyant capsule, which allows free movement with the flow. It contains measurement devices that log the temperature, absolute pressure (immersion depth) and 3D-acceleration data. A careful calibration including an uncertainty analysis has been performed. Furthermore, autonomous operation of the developed prototype was successfully proven in a flow experiment in a stirred reactor model. It showed that the sensor particle is feasible for future application in fermentation reactors and other industrial processes.

Enhancing the capability of the research fleet.

NASA Astrophysics Data System (ADS)

Pinkel, R.

2012-12-01

While the performance and economics of our vessels and manned platforms are fixed by fundamental principles, their scientific capabilities can be considerably extended through the development of new technology. Potential future systems include multi-beam swath- mapping sonars for 3-D imaging of plankton patchiness, wire-guided profiling velocity sensors for establishing full-ocean-depth velocity profiles, shipboard HF radar (CODAR) for mapping energetic currents, and shipboard Doppler radar for mapping the surface wave spectrum. Research vessel users should have access to undersea gliders and autonomous aircraft as well as the current AUVs. In addition, the use of manned stable platforms in an observatory setting deserves further consideration. As well as providing an ideal mount for meteorological and oceanographic sensors, the platforms can provide electrical power and a "heavy lift" capability for sea floor and water column studies. Concerted community effort will be required to develop these new technologies, not all of which will be commercially viable. A strong academic technology base is necessary.

The effects of St. John's wort extract and amitriptyline on autonomic responses of blood vessels and sweat glands in healthy volunteers.

PubMed

Siepmann, Martin; Kirch, Wilhelm; Krause, Stephanie; Joraschky, Peter; Mueck-Weymann, Michael

2004-02-01

St. John's wort extract is widely used and advertised as a "natural antidepressant" lacking autonomic side effects. This randomized, double-blind, placebo-controlled study compared the effects of St. John's wort extract on autonomic responses of blood vessels and sweat glands with those of amitriptyline and placebo. A randomized, double-blind, crossover study was performed in healthy male volunteers aged 22 to 31 years (25 +/- 3 years; mean +/- SD) years. Subjects orally received capsules with 255 to 285 mg St. John's wort extract (900 microg hypericin content), 25 mg amitriptyline, and placebo 3 times daily for periods of 14 days each with at least 14 days between. Vasoconstrictory response of cutaneous blood flow (VR) and skin conductance response (SR) following a single deep inspiration were employed as parameters of autonomic function. St. John's wort extract had no effect on VR and SR. In contrast, SR was diminished and the dilation phase of VR was prolonged following multiple dosing with amitriptyline (P < 0.05). Decreased electrodermal reactivity observed with amitriptyline reflects inhibition of acetylcholine at peripheral m3-cholinoreceptors, whereas prolongation of VR induced by the tricyclic drug may be due to sustained activation of central and/or peripheral sympathetic neurons.

Safe Maritime Autonomous Path Planning in a High Sea State

NASA Technical Reports Server (NTRS)

Ono, Masahiro; Quadrelli, Marco; Huntsberger, Terrance L.

2014-01-01

This paper presents a path planning method for sea surface vehicles that prevents capsizing and bow-diving in a high sea-state. A key idea is to use response amplitude operators (RAOs) or, in control terminology, the transfer functions from a sea state to a vessel's motion, in order to find a set of speeds and headings that results in excessive pitch and roll oscillations. This information is translated to arithmetic constraints on the ship's velocity, which are passed to a model predictive control (MPC)-based path planner to find a safe and optimal path that achieves specified goals. An obstacle avoidance capability is also added to the path planner. The proposed method is demonstrated by simulations.

The Telesupervised Adaptive Ocean Sensor Fleet (TAOSF) Architecture: Coordination of Multiple Oceanic Robot Boats

NASA Technical Reports Server (NTRS)

Elfes, Alberto; Podnar, Gregg W.; Dolan, John M.; Stancliff, Stephen; Lin, Ellie; Hosler, Jeffrey C.; Ames, Troy J.; Higinbotham, John; Moisan, John R.; Moisan, Tiffany A.;

Quantitative Evaluation of Stereo Visual Odometry for Autonomous Vessel Localisation in Inland Waterway Sensing Applications

PubMed Central

Kriechbaumer, Thomas; Blackburn, Kim; Breckon, Toby P.; Hamilton, Oliver; Rivas Casado, Monica

2015-01-01

Autonomous survey vessels can increase the efficiency and availability of wide-area river environment surveying as a tool for environment protection and conservation. A key challenge is the accurate localisation of the vessel, where bank-side vegetation or urban settlement preclude the conventional use of line-of-sight global navigation satellite systems (GNSS). In this paper, we evaluate unaided visual odometry, via an on-board stereo camera rig attached to the survey vessel, as a novel, low-cost localisation strategy. Feature-based and appearance-based visual odometry algorithms are implemented on a six degrees of freedom platform operating under guided motion, but stochastic variation in yaw, pitch and roll. Evaluation is based on a 663 m-long trajectory (>15,000 image frames) and statistical error analysis against ground truth position from a target tracking tachymeter integrating electronic distance and angular measurements. The position error of the feature-based technique (mean of ±0.067 m) is three times smaller than that of the appearance-based algorithm. From multi-variable statistical regression, we are able to attribute this error to the depth of tracked features from the camera in the scene and variations in platform yaw. Our findings inform effective strategies to enhance stereo visual localisation for the specific application of river monitoring. PMID:26694411

Low-frequency dynamics of autonomic regulation of circulatory system in healthy subjects

NASA Astrophysics Data System (ADS)

Skazkina, V. V.; Borovkova, E. I.; Galushko, T. A.; Khorev, V. S.; Kiselev, A. R.

2018-04-01

The paper is devoted to the analysis of dynamic of interactions between signals of autonomic circulatory regulation. We investigated two-hour experimental records of 30 healthy people. Phase synchronization was studied using the signals of the electrocardiogram and the photoplethysmogram of vessels. We found the presence of long synchronous intervals in some subjects. For analysis of the dynamic we calculated autocorrelation functions. The analysis made it possible to reveal indirect signs of the influence of the humoral regulation system.

76 FR 77806 - International Affairs; U.S. Fish Quotas in the Northwest Atlantic Fisheries Organization...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-14

... available from Douglas Christel, at the NMFS Northeast Regional Office at 55 Great Republic Drive..., autonomous vessel monitoring system; and adherence to all relevant minimum size, gear, bycatch, and other...

[Tilt test and orthostatic intolerance: abnormalities in the neural sympathetic response to gravitational stimulus].

PubMed

Furlan, R

2001-05-01

In the present manuscript the different methodologies aimed at assessing the autonomic profile in humans during a gravitational stimulus have been described. In addition, strengths and drawbacks of the tilt test in relation to occasional orthostatic intolerance were addressed. Finally, different autonomic abnormalities underlying occasional and chronic orthostatic intolerance syndromes have been schematically highlighted. The direct recording of the neural sympathetic discharge from the peroneal nerve (MSNA), in spite of its invasive nature, still represents the recognized reference to quantify the changes in the sympathetic activity to the vessels attending postural modifications. The increase of plasma norepinephrine during a tilt test is achieved by both an increase in plasma spillover and a concomitant decrease in systemic clearance. Changes in the indices of cardiac sympathetic and vagal modulation may also be quantified during a tilt test by power spectrum analysis of RR interval variability. The spectral markers of cardiac autonomic control, if evaluated concomitantly with MSNA, may contribute to assess abnormalities in the regional distribution of the sympathetic activity to the heart and the vessels. The capability of the tilt test of reproducing a vasovagal event or of inducing "false positive responses" seems to be markedly affected by the age, thus suggesting that additional or different etiopathogenetic mechanisms might be involved in the loss of consciousness in older as compared to younger subjects. In subjects suffering from occasional or habitual neurally mediated syncope an increase or, respectively, a decrease in cardiac and vascular sympathetic modulation has been documented before the loss of consciousness. In patients with pure autonomic failure, a global dysautonomia affecting both the sympathetic and the vagal modulation to the heart, seems to be present. In chronic orthostatic intolerance, the most common form of dysautonomia of young women, an abnormal regional distribution of sympathetic activity has been hypothesized during up-right posture. Indeed, during standing a blunted increase of sympathetic activity to the vessels is attended by a cardiac sympathetic overactivity leading to an exaggerated tachycardia.

Submarine and Autonomous Vessel Proliferation: Implications for Future Strategic Stability at Sea

DTIC Science & Technology

2012-12-01

missile.4 These important details of the legacy of the Cold War at sea are too often forgotten in today’s retelling of the story . Yet, as CDR (USN...vented deadly fumes. The damaged and still-burning vessel was scuttled with its nuclear weapons and reactors aboard. 8 Pavel Podvig, ed., Russian ...exception of China in the 1950s,13 the Russians generally did not provide production technology and refrained from offering sophisticated offensive systems

POSTMAN: Point of Sail Tacking for Maritime Autonomous Navigation

NASA Technical Reports Server (NTRS)

Huntsberger, Terrance L.; Reinhart, Felix

2012-01-01

Waves apply significant forces to small boats, in particular when such vessels are moving at a high speed in severe sea conditions. In addition, small high-speed boats run the risk of diving with the bow into the next wave crest during operations in the wavelengths and wave speeds that are typical for shallow water. In order to mitigate the issues of autonomous navigation in rough water, a hybrid controller called POSTMAN combines the concept of POS (point of sail) tack planning from the sailing domain with a standard PID (proportional-integral-derivative) controller that implements reliable target reaching for the motorized small boat control task. This is an embedded, adaptive software controller that uses look-ahead sensing in a closed loop method to perform path planning for safer navigation in rough waters. State-of-the-art controllers for small boats are based on complex models of the vessel's kinematics and dynamics. They enable the vessel to follow preplanned paths accurately and can theoretically control all of the small boat s six degrees of freedom. However, the problems of bow diving and other undesirable incidents are not addressed, and it is questionable if a six-DOF controller with basically a single actuator is possible at all. POSTMAN builds an adaptive capability into the controller based on sensed wave characteristics. This software will bring a muchneeded capability to unmanned small boats moving at high speeds. Previously, this class of boat was limited to wave heights of less than one meter in the sea states in which it could operate. POSTMAN is a major advance in autonomous safety for small maritime craft.

76 FR 72907 - International Affairs; U.S. Fishing Opportunity in the Northwest Atlantic Fisheries Organization...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-28

... Great Republic Drive, Gloucester, MA 01930 (phone: (978) 281-9141, fax: (978) 281-9135, email: douglas..., autonomous vessel monitoring system; and adherence to all relevant minimum size, gear, bycatch, and other...

77 FR 74467 - International Affairs; U.S. Fishing Opportunities in the Northwest Atlantic Fisheries...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-14

... Regional Office at 55 Great Republic Drive, Gloucester, MA 01930 (phone: 978-281-9141, fax: 978-281-9135...; presence of an on-board observer; deployment of a functioning, autonomous vessel monitoring system...

GEBCO-NF Alumni Team's entry for Shell Ocean Discovery XPRIZE. An innovative seafloor mapping system of an AUV integrated with the newly designed USV SEA-KIT.

NASA Astrophysics Data System (ADS)

Wigley, R. A.; Anderson, R.; Bazhenova, E.; Falconer, R. K. H.; Kearns, T.; Martin, T.; Minami, H.; Roperez, J.; Rosedee, A.; Ryzhov, I.; Sade, H.; Seeboruth, S.; Simpson, B.; Sumiyoshi, M.; Tinmouth, N.; Zarayskaya, Y.; Zwolak, K.

2017-12-01

The international team of Nippon Foundation/GEBCO Alumni was formed to compete in the Shell Ocean Discovery XPRIZE competition. The aim of the Team is to build an innovative seafloor mapping system, not only to successfully compete in the XPRIZE challenge, but also to make a step towards autonomously mapping the complex global seafloor at resolutions not achievable by standard surface mapping systems. This new technology is linked to goals of the recently announced Nippon Foundation-GEBCO Seabed 2030 Project, aiming in highest possible resolution bathymetric mapping of global World Ocean floor by 2030. The mapping system is composed of three main elements: an Unmanned Surface Vessel (USV), an Autonomous Underwater Vehicle (AUV) and an on-shore control station. A newly designed, USV, called SEA-KIT, was be built to interact with any AUV, acting as remote surface access to the deep ocean. The major function of the SEA-KIT in the system design is 1) the potential transportation of a commercially available AUV to and from the launch site to the survey site and 2) the deployment and recovery of the AUV. In further development stages, options for AUV charging and data transfer are considered. Additionally, the SEA-KIT will offer a positioning solution during AUV operations, utilizing an Ultra Short Base Line (USBL) acoustic system. The data acquisition platform (AUV) is equipped with a high-end technology interferometric sonar with synthetic aperture options, providing the possibility of collecting bathymetric data co-registered with seafloor object imagery. An automated data processing workflow is highly desirable due to the large amount of data collected during each mission. The processing workflow is being designed to be as autonomous as possible and an algorithm for automated data processing onboard are being considered to reduce the time of data processing and make a final products available as soon as possible after the completion of data collection. No human intervention on site is required for the operation of data collection using the integrated USV and AUV mapping system. The on-shore control station only plays a supervision role and is able to assess the USV performance, while AUV works autonomously, according to a previously set survey plan. This leads to lower-risk, less-effort deep ocean mapping.

The telesupervised adaptive ocean sensor fleet

NASA Astrophysics Data System (ADS)

Elfes, Alberto; Podnar, Gregg W.; Dolan, John M.; Stancliff, Stephen; Lin, Ellie; Hosler, Jeffrey C.; Ames, Troy J.; Moisan, John; Moisan, Tiffany A.; Higinbotham, John; Kulczycki, Eric A.

2007-09-01

We are developing a multi-robot science exploration architecture and system called the Telesupervised Adaptive Ocean Sensor Fleet (TAOSF). TAOSF uses a group of robotic boats (the OASIS platforms) to enable in-situ study of ocean surface and sub-surface phenomena. The OASIS boats are extended-deployment autonomous ocean surface vehicles, whose development is funded separately by the National Oceanic and Atmospheric Administration (NOAA). The TAOSF architecture provides an integrated approach to multi-vehicle coordination and sliding human-vehicle autonomy. It allows multiple mobile sensing assets to function in a cooperative fashion, and the operating mode of the vessels to range from autonomous control to teleoperated control. In this manner, TAOSF increases data-gathering effectiveness and science return while reducing demands on scientists for tasking, control, and monitoring. It combines and extends prior related work done by the authors and their institutions. The TAOSF architecture is applicable to other areas where multiple sensing assets are needed, including ecological forecasting, water management, carbon management, disaster management, coastal management, homeland security, and planetary exploration. The first field application chosen for TAOSF is the characterization of Harmful Algal Blooms (HABs). Several components of the TAOSF system have been tested, including the OASIS boats, the communications and control interfaces between the various hardware and software subsystems, and an airborne sensor validation system. Field tests in support of future HAB characterization were performed under controlled conditions, using rhodamine dye as a HAB simulant that was dispersed in a pond. In this paper, we describe the overall TAOSF architecture and its components, discuss the initial tests conducted and outline the next steps.

Smooth muscle cell recruitment to lymphatic vessels requires PDGFB and impacts vessel size but not identity.

PubMed

Wang, Yixin; Jin, Yi; Mäe, Maarja Andaloussi; Zhang, Yang; Ortsäter, Henrik; Betsholtz, Christer; Mäkinen, Taija; Jakobsson, Lars

2017-10-01

Tissue fluid drains through blind-ended lymphatic capillaries, via smooth muscle cell (SMC)-covered collecting vessels into venous circulation. Both defective SMC recruitment to collecting vessels and ectopic recruitment to lymphatic capillaries are thought to contribute to vessel failure, leading to lymphedema. However, mechanisms controlling lymphatic SMC recruitment and its role in vessel maturation are unknown. Here, we demonstrate that platelet-derived growth factor B (PDGFB) regulates lymphatic SMC recruitment in multiple vascular beds. PDGFB is selectively expressed by lymphatic endothelial cells (LECs) of collecting vessels. LEC-specific deletion of Pdgfb prevented SMC recruitment causing dilation and failure of pulsatile contraction of collecting vessels. However, vessel remodelling and identity were unaffected. Unexpectedly, Pdgfb overexpression in LECs did not induce SMC recruitment to capillaries. This was explained by the demonstrated requirement of PDGFB extracellular matrix (ECM) retention for lymphatic SMC recruitment, and the low presence of PDGFB-binding ECM components around lymphatic capillaries. These results demonstrate the requirement of LEC-autonomous PDGFB expression and retention for SMC recruitment to lymphatic vessels, and suggest an ECM-controlled checkpoint that prevents SMC investment of capillaries, which is a common feature in lymphedematous skin. © 2017. Published by The Company of Biologists Ltd.

Numerical modeling of dynamics of heart rate and arterial pressure during passive orthostatic test

NASA Astrophysics Data System (ADS)

Ishbulatov, Yu. M.; Kiselev, A. R.; Karavaev, A. S.

2018-04-01

A model of human cardiovascular system is proposed to describe the main heart rhythm, influence of autonomous regulation on frequency and strength of heart contractions and resistance of arterial vessels; process of formation of arterial pressure during systolic and diastolic phases; influence of respiration; synchronization between loops of autonomous regulation. The proposed model is used to simulate the dynamics of heart rate and arterial pressure during passive transition from supine to upright position. Results of mathematical modeling are compared to original experimental data.

76 FR 464 - Notification of U.S. Fish Quotas and an Effort Allocation in the Northwest Atlantic Fisheries...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-05

... Northeast Regional Office at 55 Great Republic Drive, Gloucester, MA 01930 (phone: 978- 281-9103, fax: 978..., autonomous vessel monitoring system; and adherence to all relevant minimum size, gear, bycatch, and other...

76 FR 21772 - Navigation Safety Advisory Council

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-18

..., routing measures, marine information, diving safety, and aids to navigation systems. Agenda The NAVSAC... discussion of autonomous unmanned vessels and discuss their implications for the Inland Navigation Rules. A... DEPARTMENT OF HOMELAND SECURITY Coast Guard [Docket No. USCG-2011-0204] Navigation Safety Advisory...

AUTONOMIC AXONS IN THE HUMAN ENDOCRINE PANCREAS SHOW UNIQUE INNERVATION PATTERNS

PubMed Central

Rodriguez-Diaz, Rayner; Abdulreda, Midhat H.; Formoso, Alexander L.; Gans, Itai; Ricordi, Camillo; Berggren, Per-Olof; Caicedo, Alejandro

2011-01-01

SUMMARY The autonomic nervous system regulates hormone secretion from the endocrine pancreas, the islets of Langerhans, and thus impacts glucose metabolism. The parasympathetic and sympathetic nerves innervate the pancreatic islet, but the precise innervation patterns are not known, particularly in human islets. Here we demonstrate that the innervation of human islets is different from that of mouse islets and that it does not conform to existing models of autonomic control of islet function. By visualizing axons in three dimensions and quantifying axonal densities and contacts within pancreatic islets, we found that, in contrast to mouse endocrine cells, human endocrine cells are sparsely contacted by autonomic axons. Few parasympathetic cholinergic axons penetrate the human islet and the invading sympathetic fibers preferentially innervate smooth muscle cells of blood vessels located within the islet. Thus, rather than modulating endocrine cell function directly, sympathetic nerves may regulate hormone secretion in human islets by controlling local blood flow or by acting on islet regions located downstream. PMID:21723503

Evaluating a vessel for suitability for containing fluid

DOEpatents

Barefield, II, James E.; Judge, Elizabeth J.; Le, Loan A.; Lopez, Leon N.; Beveridge, Andrew C.; Chapman, Daniel R.; Taylor, Seth T.

2017-05-30

A method for evaluating a vessel for suitability to contain a fluid includes providing a vessel and forming a polished surface portion of the vessel by removing oxidation and/or contaminants from a portion of the vessel. The method further includes applying a focused laser to the polished surface portion to form plasma on the polished surface portion, and determining whether the vessel is suitable for containing a fluid based on silicon content of the polished surface portion. The silicon content is estimated based on light emitted from the plasma.

Development of a Semi-Autonomous Underwater Vehicle for Intervention Missions

DTIC Science & Technology

2000-10-30

Alexander Malahoff of the University of Hawaii, Dr. Homayoun Seraji of the Jet Propulsion Laboratory, and Mr. Dick Turlington of the Pacific Missile...AUV. The angular orientation sensor is housed within a 1-inch OD cylindrical pressure vessel (6000-m capable) made low- Fe grade-2 titanium. For a

Three-dimensional ocean sensor networks: A survey

NASA Astrophysics Data System (ADS)

Wang, Yu; Liu, Yingjian; Guo, Zhongwen

2012-12-01

The past decade has seen a growing interest in ocean sensor networks because of their wide applications in marine research, oceanography, ocean monitoring, offshore exploration, and defense or homeland security. Ocean sensor networks are generally formed with various ocean sensors, autonomous underwater vehicles, surface stations, and research vessels. To make ocean sensor network applications viable, efficient communication among all devices and components is crucial. Due to the unique characteristics of underwater acoustic channels and the complex deployment environment in three dimensional (3D) ocean spaces, new efficient and reliable communication and networking protocols are needed in design of ocean sensor networks. In this paper, we aim to provide an overview of the most recent advances in network design principles for 3D ocean sensor networks, with focuses on deployment, localization, topology design, and position-based routing in 3D ocean spaces.

Towards Autonomous Airport Surface Operations: NextGen Flight Deck Implications

NASA Technical Reports Server (NTRS)

Foyle, David C.; Hooey, Becky Lee; Bakowski, Deborah Lee

2017-01-01

Surface Trajectory-based Operations (STBO) is a potential concept candidate for flight deck autonomous operations. Existing research will be reviewed and possible architectures and research issues will be presented.

Global Coastal and Marine Spatial Planning (CMSP) from Space Based AIS Ship Tracking

NASA Astrophysics Data System (ADS)

Schwehr, K. D.; Foulkes, J. A.; Lorenzini, D.; Kanawati, M.

2011-12-01

All nations need to be developing long term integrated strategies for how to use and preserve our natural resources. As a part of these strategies, we must evalutate how communities of users react to changes in rules and regulations of ocean use. Global characterization of the vessel traffic on our Earth's oceans is essential to understanding the existing uses to develop international Coast and Marine Spatial Planning (CMSP). Ship traffic within 100-200km is beginning to be effectively covered in low latitudes by ground based receivers collecting position reports from the maritime Automatic Identification System (AIS). Unfortunately, remote islands, high latitudes, and open ocean Marine Protected Areas (MPA) are not covered by these ground systems. Deploying enough autonomous airborne (UAV) and surface (USV) vessels and buoys to provide adequate coverage is a difficult task. While the individual device costs are plummeting, a large fleet of AIS receivers is expensive to maintain. The global AIS coverage from SpaceQuest's low Earth orbit satellite receivers combined with the visualization and data storage infrastructure of Google (e.g. Maps, Earth, and Fusion Tables) provide a platform that enables researchers and resource managers to begin answer the question of how ocean resources are being utilized. Near real-time vessel traffic data will allow managers of marine resources to understand how changes to education, enforcement, rules, and regulations alter usage and compliance patterns. We will demonstrate the potential for this system using a sample SpaceQuest data set processed with libais which stores the results in a Fusion Table. From there, the data is imported to PyKML and visualized in Google Earth with a custom gx:Track visualization utilizing KML's extended data functionality to facilitate ship track interrogation. Analysts can then annotate and discuss vessel tracks in Fusion Tables.

Autonomous Aerobraking: Thermal Analysis and Response Surface Development

NASA Technical Reports Server (NTRS)

Dec, John A.; Thornblom, Mark N.

2011-01-01

A high-fidelity thermal model of the Mars Reconnaissance Orbiter was developed for use in an autonomous aerobraking simulation study. Response surface equations were derived from the high-fidelity thermal model and integrated into the autonomous aerobraking simulation software. The high-fidelity thermal model was developed using the Thermal Desktop software and used in all phases of the analysis. The use of Thermal Desktop exclusively, represented a change from previously developed aerobraking thermal analysis methodologies. Comparisons were made between the Thermal Desktop solutions and those developed for the previous aerobraking thermal analyses performed on the Mars Reconnaissance Orbiter during aerobraking operations. A variable sensitivity screening study was performed to reduce the number of variables carried in the response surface equations. Thermal analysis and response surface equation development were performed for autonomous aerobraking missions at Mars and Venus.

Detecting terrorist nuclear weapons at sea: The 10th door problem

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

Slaughter, D R

2008-09-15

While screening commercial cargo containers for the possible presence of WMD is important and necessary smugglers have successfully exploited the many other vehicles transporting cargo into the US including medium and small vessels at sea. These vessels provide a venue that is currently not screened and widely used. Physics limits that make screening of large vessels prohibitive impractical do not prohibit effective screening of the smaller vessels. While passive radiation detection is probably ineffective at sea active interrogation may provide a successful approach. The physics limits of active interrogation of ships at sea from standoff platforms are discussed. Autonomous platformsmore » that could carry interrogation systems at sea, both airborne and submersible, are summarized and their utilization discussed. An R&D program to investigate the limits of this approach to screening ships at sea is indicated and limitations estimated.« less

Recent Advances in Bathymetric Surveying of Continental Shelf Regions Using Autonomous Vehicles

NASA Astrophysics Data System (ADS)

Holland, K. T.; Calantoni, J.; Slocum, D.

2016-02-01

Obtaining bathymetric observations within the continental shelf in areas closer to the shore is often time consuming and dangerous, especially when uncharted shoals and rocks present safety concerns to survey ships and launches. However, surveys in these regions are critically important to numerical simulation of oceanographic processes, as bathymetry serves as the bottom boundary condition in operational forecasting models. We will present recent progress in bathymetric surveying using both traditional vessels retrofitted for autonomous operations and relatively inexpensive, small team deployable, Autonomous Underwater Vehicles (AUV). Both systems include either high-resolution multibeam echo sounders or interferometric sidescan sonar sensors with integrated inertial navigation system capabilities consistent with present commercial-grade survey operations. The advantages and limitations of these two configurations employing both unmanned and autonomous strategies are compared using results from several recent survey operations. We will demonstrate how sensor data collected from unmanned platforms can augment or even replace traditional data collection technologies. Oceanographic observations (e.g., sound speed, temperature and currents) collected simultaneously with bathymetry using autonomous technologies provide additional opportunities for advanced data assimilation in numerical forecasts. Discussion focuses on our vision for unmanned and autonomous systems working in conjunction with manned or in-situ systems to optimally and simultaneously collect data in environmentally hostile or difficult to reach areas.

Some properties of the walls of metaxylem vessels of maize roots, including tests of the wettability of their lumenal wall surfaces

PubMed Central

McCully, Margaret; Canny, Martin; Baker, Adam; Miller, Celia

2014-01-01

Background and Aims Since the proposal of the cohesion theory there has been a paradox that the lumenal surface of vessels is rich in hydrophobic lignin, while tension in the rising sap requires adhesion to a hydrophilic surface. This study sought to characterize the strength of that adhesion in maize (Zea mays), the wettability of the vessel surface, and to reconcile this with its histochemical and physical nature. Methods Wettability was assessed by emptying the maize root vessels of sap, perfusing them with either water or oil, and examining the adhesion (as revealed by contact angles) of the two liquids to vessel walls by cryo-scanning electron microscopy. The phobicity of the lumenal surface was also assessed histochemically with hydrophilic and hydrophobic probes. Key Results Pit borders in the lumen-facing vessel wall surface were wetted by both sap/water and oil. The attraction for oil was weaker: water could replace oil but not vice versa. Pit apertures repelled oil and were strongly stained by hydrophilic probes. Pit chambers were probably hydrophilic. Oil never entered the pits. When vessels were emptied and cryo-fixed immediately, pit chambers facing away from the vessels were always sap-filled. Pit chambers facing vessel lumens were either sap- or gas-filled. Sap from adjoining tracheary elements entering empty vessels accumulated on the lumenal surface in hemispherical drops, which spread out with decreasing contact angles to fill the lumen. Conclusions The vessel lumenal surface has a dual nature, namely a mosaic of hydrophilic and hydrophobic patches at the micrometre scale, with hydrophilic predominating. A key role is shown, for the first time, of overarching borders of pits in determining the dual nature of the surface. In gas-filled (embolized) vessels they are hydrophobic. When wetted by sap (vessels refilling or full) they are hydrophilic. A hypothesis is proposed to explain the switch between the two states. PMID:24709790

Use of an Autonomous Surface Vehicle reveals small-scale diel vertical migrations of zooplankton and susceptibility to light pollution under low solar irradiance.

PubMed

Ludvigsen, Martin; Berge, Jørgen; Geoffroy, Maxime; Cohen, Jonathan H; De La Torre, Pedro R; Nornes, Stein M; Singh, Hanumant; Sørensen, Asgeir J; Daase, Malin; Johnsen, Geir

2018-01-01

Light is a major cue for nearly all life on Earth. However, most of our knowledge concerning the importance of light is based on organisms' response to light during daytime, including the dusk and dawn phase. When it is dark, light is most often considered as pollution, with increasing appreciation of its negative ecological effects. Using an Autonomous Surface Vehicle fitted with a hyperspectral irradiance sensor and an acoustic profiler, we detected and quantified the behavior of zooplankton in an unpolluted light environment in the high Arctic polar night and compared the results with that from a light-polluted environment close to our research vessels. First, in environments free of light pollution, the zooplankton community is intimately connected to the ambient light regime and performs synchronized diel vertical migrations in the upper 30 m despite the sun never rising above the horizon. Second, the vast majority of the pelagic community exhibits a strong light-escape response in the presence of artificial light, observed down to 100 m. We conclude that artificial light from traditional sampling platforms affects the zooplankton community to a degree where it is impossible to examine its abundance and natural rhythms within the upper 100 m. This study underscores the need to adjust sampling platforms, particularly in dim-light conditions, to capture relevant physical and biological data for ecological studies. It also highlights a previously unchartered susceptibility to light pollution in a region destined to see significant changes in light climate due to a reduced ice cover and an increased anthropogenic activity.

Characterization of sun and sky glint from wind ruffled sea surfaces for improved estimation of polarized remote sensing reflectance

NASA Astrophysics Data System (ADS)

Foster, Robert; Ibrahim, Amir; Gilerson, Alex; El-Habashi, Ahmed; Carrizo, Carlos; Ahmed, Sam

2015-09-01

During two cruises in 2014, the polarized radiance of the ocean and the sky were continuously acquired using a HyperSAS-POL system. The system consists of seven hyperspectral radiometric sensors, three of which (one unpolarized and two polarized) look at the water and similarly three at the sky. The system autonomously tracks the Sun position and the heading of the research vessel to which it is attached in order to maintain a fixed relative azimuth angle with respect to the Sun (i.e. 90°) and therefore avoid the specular reflection of the sunlight. For the duration of both cruises, (NASA Ship Aircraft Bio-Optical Research (SABOR), and NOAA VIIRS Validation/Calibration), in situ inherent optical properties (IOPs) were continuously acquired using a set of instrument packages modified for underway measurement, and hyperspectral radiometric measurements were taken manually at all stations. During SABOR, an underwater polarimeter was deployed when conditions permitted. All measurements were combined in an effort to first develop a glint (sky + Sun) correction scheme for the upwelling polarized signal from a wind driven ocean surface and compare with one assuming that the ocean surface is flat.

Oceanids command and control (C2) data system - Marine autonomous systems data for vehicle piloting, scientific data users, operational data assimilation, and big data

NASA Astrophysics Data System (ADS)

Buck, J. J. H.; Phillips, A.; Lorenzo, A.; Kokkinaki, A.; Hearn, M.; Gardner, T.; Thorne, K.

2017-12-01

The National Oceanography Centre (NOC) operate a fleet of approximately 36 autonomous marine platforms including submarine gliders, autonomous underwater vehicles, and autonomous surface vehicles. Each platform effectivity has the capability to observe the ocean and collect data akin to a small research vessel. This is creating a growth in data volumes and complexity while the amount of resource available to manage data remains static. The OceanIds Command and Control (C2) project aims to solve these issues by fully automating the data archival, processing and dissemination. The data architecture being implemented jointly by NOC and the Scottish Association for Marine Science (SAMS) includes a single Application Programming Interface (API) gateway to handle authentication, forwarding and delivery of both metadata and data. Technicians and principle investigators will enter expedition data prior to deployment of vehicles enabling automated data processing when vehicles are deployed. The system will support automated metadata acquisition from platforms as this technology moves towards operational implementation. The metadata exposure to the web builds on a prototype developed by the European Commission supported SenseOCEAN project and is via open standards including World Wide Web Consortium (W3C) RDF/XML and the use of the Semantic Sensor Network ontology and Open Geospatial Consortium (OGC) SensorML standard. Data will be delivered in the marine domain Everyone's Glider Observatory (EGO) format and OGC Observations and Measurements. Additional formats will be served by implementation of endpoints such as the NOAA ERDDAP tool. This standardised data delivery via the API gateway enables timely near-real-time data to be served to Oceanids users, BODC users, operational users and big data systems. The use of open standards will also enable web interfaces to be rapidly built on the API gateway and delivery to European research infrastructures that include aligned reference models for data infrastructure.

Molten metal containment vessel with rare earth oxysulfide protective coating thereon and method of making same

DOEpatents

Krikorian, Oscar H.; Curtis, Paul G.

1992-01-01

An improved molten metal containment vessel is disclosed in which wetting of the vessel's inner wall surfaces by molten metal is inhibited by coating at least the inner surfaces of the containment vessel with one or more rare earth oxysulfide or rare earth sulfide compounds to inhibit wetting and or adherence by the molten metal to the surfaces of the containment vessel.

Salinity Processes in the Upper Ocean Regional Study (SPURS)

NASA Image and Video Library

2012-09-04

Autonomous wave gliders are seen onboard the the Woods Hole Oceanographic Institution research vessel Knorr on Tuesday, Sept. 4, 2012, in Woods Hole, Mass. The autonomous gliders will be deployed in the Atlantic Ocean as part of the Salinity Processes in the Upper Ocean Regional Study (SPURS) which is set to sail on Sept. 6. The NASA-sponsored expedition will sail to the North Atlantic's saltiest spot to get a detailed, 3-D picture of how salt content fluctuates in the ocean's upper layers and how these variations are related to shifts in rainfall patterns around the planet. Photo Credit: (NASA/Bill Ingalls)

Salinity Processes in the Upper Ocean Regional Study (SPURS)

NASA Image and Video Library

2012-09-04

Autonomous wave gliders, right, are seen onboard the the Woods Hole Oceanographic Institution research vessel Knorr on Tuesday, Sept. 4, 2012, in Woods Hole, Mass. The autonomous gliders will be deployed in the Atlantic Ocean as part of the Salinity Processes in the Upper Ocean Regional Study (SPURS) which is set to sail on Sept. 6. The NASA-sponsored expedition will sail to the North Atlantic's saltiest spot to get a detailed, 3-D picture of how salt content fluctuates in the ocean's upper layers and how these variations are related to shifts in rainfall patterns around the planet. Photo Credit: (NASA/Bill Ingalls)

Salinity Processes in the Upper Ocean Regional Study (SPURS)

NASA Image and Video Library

2012-09-04

NASA Physical Oceanography Program Scientist Eric Lindstrom inspects an autonomous wave glider onboard the Woods Hole Oceanographic Institution research vessel Knorr on Tuesday, Sept. 4, 2012, in Woods Hole, Mass. The autonomous gliders will be deployed in the Atlantic Ocean as part of the Salinity Processes in the Upper Ocean Regional Study (SPURS) which is set to sail on Sept. 6. The NASA-sponsored expedition will sail to the North Atlantic's saltiest spot to get a detailed, 3-D picture of how salt content fluctuates in the ocean's upper layers and how these variations are related to shifts in rainfall patterns around the planet. Photo Credit: (NASA/Bill Ingalls)

Development of a Semi-Autonomous Underwater Vehicle for Intervention Missions

DTIC Science & Technology

2002-06-30

Cancilliere of the Naval Undersea Warfare Center, Dr. Alexander Malahoff of the University of Hawaii, Dr. Homayoun Seraji of the Jet Propulsion Laboratory...1-inch OD cylindrical pressure vessel (6000-m capable) made low- Fe grade-2 titanium. For a 6000-m depth capability, we have constructed a 7071-grade

A Systems Engineering Approach to the Development of an Autonomous Sailing Vessel

DTIC Science & Technology

2011-01-01

netbook . Power issues and heat dissipation must also be considered in the selection process. Actuation: Because the system is designed to allow a...use of a lap- top or netbook as the primary processor. While we have used a small form com- puter (Pico system) in the past, the Technical Support

Modeling and control of tissue compression and temperature for automation in robot-assisted surgery.

PubMed

Sinha, Utkarsh; Li, Baichun; Sankaranarayanan, Ganesh

2014-01-01

Robotic surgery is being used widely due to its various benefits that includes reduced patient trauma and increased dexterity and ergonomics for the operating surgeon. Making the whole or part of the surgical procedure autonomous increases patient safety and will enable the robotic surgery platform to be used in telesurgery. In this work, an Electrosurgery procedure that involves tissue compression and application of heat such as the coaptic vessel closure has been automated. A MIMO nonlinear model characterizing the tissue stiffness and conductance under compression was feedback linearized and tuned PID controllers were used to control the system to achieve both the displacement and temperature constraints. A reference input for both the constraints were chosen as a ramp and hold trajectory which reflect the real constraints that exist in an actual surgical procedure. Our simulations showed that the controllers successfully tracked the reference trajectories with minimal deviation and in finite time horizon. The MIMO system with controllers developed in this work can be used to drive a surgical robot autonomously and perform electrosurgical procedures such as coaptic vessel closures.

Guarded Flat Plate Cryogenic Test Apparatus and Calorimeter

NASA Technical Reports Server (NTRS)

Fesmire, James E. (Inventor); Johnson, Wesley L. (Inventor)

2017-01-01

A test apparatus for thermal energy measurement of disk-shaped test specimens has a cold mass assembly locatable within a sealable chamber with a guard vessel having a guard chamber to receive a liquid fluid and a bottom surface to contact a cold side of a test specimen, and a test vessel having a test chamber to receive a liquid fluid and encompassed on one side by a center portion of the bottom surface shared with the guard vessel. A lateral wall assembly of the test vessel is closed by a vessel top, the lateral wall assembly comprising an outer wall and an inner wall having opposing surfaces that define a thermal break including a condensable vapor pocket to inhibit heat transfer through the lateral wall from the guard vessel to the test vessel. A warm boundary temperature surface is in thermal communication with a lower surface of the test specimen.

Innervation pattern of the preocular human central retinal artery.

PubMed

Bergua, Antonio; Kapsreiter, Markus; Neuhuber, Winfried L; Reitsamer, Herbert A; Schrödl, Falk

2013-05-01

The central retinal artery (CRA) is the main vessel for inner retinal oxygen and nutrition supply. While the intraocular branches lack autonomic innervation, the innervation pattern of the extra-ocular part of this vessel along its course within the optic nerve is poorly investigated. This part however is essential for maintenance of retinal blood supply, in physiological and pathological conditions. Therefore, the aim of this study was the characterization of the autonomic innervation of the preocular CRA in humans with morphological methods. Meeting the Declaration of Helsinki, eyes of body or cornea donors were processed for single or double immunohistochemistry against tyrosine hydroxilase (TH), dopamine-β-hydroxylase (DBH), choline acetyl-transferase (ChAT), vesicular acetylcholine transporter (VAChT), neuronal nitric oxide synthase (nNOS), calcitonin gene-related peptide (CGRP), substance P (SP), vasoactive intestinal polypeptide (VIP), and cytochemistry for NADPH-diaphorase (NADPH-d). For documentation, light-, fluorescence-, and confocal laser-scanning microscopy were used. TH and DBH immunoreactive nerve fibres were detected in the CRA vessel wall, although a distinct perivascular plexus was missing. Further, nerve fibres immunoreactive for ChAT and VAChT were found, while CGRP, SP, and VIP were not detected. NADPH-d staining revealed scattered nerve fibres in the adventitia of the CRA and in close vicinity; however, nNOS-immunostaining could not confirm this finding. The CRA receives adrenergic and cholinergic innervations, indicating sympathetic and parasympathetic components, respectively. Remarkably, a peptidergic primary afferent innervation was missing. Since clinical results suggest an autoregulation of intraretinal vessels, further studies are needed to clarify the impact of CRA innervation for retinal perfusion. Copyright © 2012 Elsevier Ltd. All rights reserved.

Cerebro-afferent vessel and pupillary basal diameter variation induced by stomatognathic trigeminal proprioception: a case report.

PubMed

De Cicco, Vincenzo

2012-09-03

A patient affected by asymmetric hemodynamics of cerebro-afferent vessels underwent duplex color scanner investigations in occlusal proprioceptive un- and rebalance conditions. Pupillometric video-oculographic examinations were performed in order to spot connected trigeminal proprioceptive motor patterns able to interfere on sympathetic autonomic activity. The aim of this case report is to verify if involuntary jaw closing during swallowing, executed in unbalance and rebalance myoelectric activity, would be able to modify cerebral hemodynamics. A 56-year-old Caucasian Italian woman affected by asymmetric blood flow of cerebro-afferent vessels underwent an electromyographic investigation of her occlusal muscles in order to assess their occlusal functional balance. The extreme asymmetry of myoelectric activity in dental occlusion evidenced by electromyographic values suggested the rebalancing of the functions of occlusal muscles through concurrent transcutaneous stimulation of the trigeminal nerve supra- and submandibular motor branches. The above-mentioned method allowed the detection of a symmetric craniomandibular muscular relation that can be kept constant through the use of a cusp bite modeled on the inferior dental arch: called orthotic-syntropic bite for its peculiar use of electrostimulation. A few days later, the patient underwent a duplex color scanner investigation and pupillometric video-oculographic examinations in occlusal unbalance and rebalance conditions. A comparative data analysis showed that an unbalanced dental occlusal function may represent an interferential pattern on cerebral hemodynamics velocity and pupillometric evaluations have proved useful both in the analysis of locus coeruleus functional modalities and as a diagnostic tool in the assessment of pathologies involving locus coeruleus and autonomic systems. The inclusion of myoelectric masseter examinations can be useful in patients with asymmetric hemodynamics of cerebro-afferent vessels and dental occlusal proprioceptive rebalance can integrate the complex therapy of patients with increased chronic sympathetic activity.

Sex hormone effects on autonomic mechanisms of thermoregulation in humans.

PubMed

Charkoudian, Nisha; Stachenfeld, Nina

2016-04-01

Autonomic mechanisms are fundamental to human physiological thermoregulation, and female reproductive hormones have substantial influences on several aspects of these mechanisms. Of these, the best recognized are the thermoregulatory responses that occur at menopause (hot flushes) and the changes in body temperature within the menstrual cycle which may help couples predict ovulation. Our goal in this brief review is to summarize current knowledge regarding the influences of reproductive hormones on autonomic mechanisms in human thermoregulation. In general, estrogens tend to promote lower body temperatures via augmentation of heat dissipation responses, whereas progesterone tends to promote higher body temperatures. Recent evidence suggests specific influences of estrogens on central autonomic nuclei involved in control of skin blood flow and sweating. Estrogens also augment vasodilation by direct effects on peripheral blood vessels. Influences of progesterone are less well understood, but include both centrally regulated changes in thermoregulatory set-point as well as and peripheral effects, including augmented vasoconstriction in the skin. We conclude with a brief discussion of thermoregulatory adjustments associated with changing hormone levels during menopause, pregnancy and polycystic ovary syndrome. Published by Elsevier B.V.

Motion correction for passive radiation imaging of small vessels in ship-to-ship inspections

NASA Astrophysics Data System (ADS)

Ziock, K. P.; Boehnen, C. B.; Ernst, J. M.; Fabris, L.; Hayward, J. P.; Karnowski, T. P.; Paquit, V. C.; Patlolla, D. R.; Trombino, D. G.

2016-01-01

Passive radiation detection remains one of the most acceptable means of ascertaining the presence of illicit nuclear materials. In maritime applications it is most effective against small to moderately sized vessels, where attenuation in the target vessel is of less concern. Unfortunately, imaging methods that can remove source confusion, localize a source, and avoid other systematic detection issues cannot be easily applied in ship-to-ship inspections because relative motion of the vessels blurs the results over many pixels, significantly reducing system sensitivity. This is particularly true for the smaller watercraft, where passive inspections are most valuable. We have developed a combined gamma-ray, stereo visible-light imaging system that addresses this problem. Data from the stereo imager are used to track the relative location and orientation of the target vessel in the field of view of a coded-aperture gamma-ray imager. Using this information, short-exposure gamma-ray images are projected onto the target vessel using simple tomographic back-projection techniques, revealing the location of any sources within the target. The complex autonomous tracking and image reconstruction system runs in real time on a 48-core workstation that deploys with the system.

Motion correction for passive radiation imaging of small vessels in ship-to-ship inspections

DOE PAGES

Ziock, Klaus -Peter; Boehnen, Chris Bensing; Ernst, Joseph M.; ...

2015-09-05

Passive radiation detection remains one of the most acceptable means of ascertaining the presence of illicit nuclear materials. In maritime applications it is most effective against small to moderately sized vessels, where attenuation in the target vessel is of less concern. Unfortunately, imaging methods that can remove source confusion, localize a source, and avoid other systematic detection issues cannot be easily applied in ship-to-ship inspections because relative motion of the vessels blurs the results over many pixels, significantly reducing system sensitivity. This is particularly true for the smaller watercraft, where passive inspections are most valuable. We have developed a combinedmore » gamma-ray, stereo visible-light imaging system that addresses this problem. Data from the stereo imager are used to track the relative location and orientation of the target vessel in the field of view of a coded-aperture gamma-ray imager. Using this information, short-exposure gamma-ray images are projected onto the target vessel using simple tomographic back-projection techniques, revealing the location of any sources within the target. Here,the complex autonomous tracking and image reconstruction system runs in real time on a 48-core workstation that deploys with the system.« less

Autonomous Graphene Vessel for Suctioning and Storing Liquid Body of Spilled Oil.

PubMed

Kim, Taewoo; Lee, Jeong Seok; Lee, Geonhui; Seo, Dong Kyun; Baek, Youngbin; Yoon, Jeyong; Oh, Seung M; Kang, Tae June; Lee, Hong H; Kim, Yong Hyup

2016-02-29

Despite remarkable strides in science and technology, the strategy for spilled oil collection has remained almost the same since the 1969 Santa Barbara oil spill. The graphene vessel devised here can bring about an important yet basic change in the strategy for spilled oil collection. When it is placed on the oil-covered seawater, the graphene vessel selectively separates the oil, then collects and stores the collected oil in the vessel all by itself without any external power inputs. Capillarity and gravity work together to fill this proto-type graphene vessel with the spilled oil at a rate that is higher than 20,000 liters per square meter per hour (LMH) with oil purity better than 99.9%, and allow the vessel to withstand a water head of 0.5 m. The vessel also has a superb chemical stability and recyclability. An expanded oil contact area, considerably greater than the thickness of the oil layer, forms at the reduced graphene oxide (rGO) foam interface upon contact with the spilled oil. This expanded contact area does not change much even when the oil layer thins out. As a result, the high oil collection rate is maintained throughout the recovery of spilled oil.

Autonomous Graphene Vessel for Suctioning and Storing Liquid Body of Spilled Oil

PubMed Central

Kim, Taewoo; Lee, Jeong Seok; Lee, Geonhui; Seo, Dong Kyun; Baek, Youngbin; Yoon, Jeyong; Oh, Seung M.; Kang, Tae June; Lee, Hong H.; Kim, Yong Hyup

2016-01-01

Despite remarkable strides in science and technology, the strategy for spilled oil collection has remained almost the same since the 1969 Santa Barbara oil spill. The graphene vessel devised here can bring about an important yet basic change in the strategy for spilled oil collection. When it is placed on the oil-covered seawater, the graphene vessel selectively separates the oil, then collects and stores the collected oil in the vessel all by itself without any external power inputs. Capillarity and gravity work together to fill this proto-type graphene vessel with the spilled oil at a rate that is higher than 20,000 liters per square meter per hour (LMH) with oil purity better than 99.9%, and allow the vessel to withstand a water head of 0.5 m. The vessel also has a superb chemical stability and recyclability. An expanded oil contact area, considerably greater than the thickness of the oil layer, forms at the reduced graphene oxide (rGO) foam interface upon contact with the spilled oil. This expanded contact area does not change much even when the oil layer thins out. As a result, the high oil collection rate is maintained throughout the recovery of spilled oil. PMID:26923622

Use of an Autonomous Surface Vehicle reveals small-scale diel vertical migrations of zooplankton and susceptibility to light pollution under low solar irradiance

PubMed Central

Ludvigsen, Martin; Berge, Jørgen; Geoffroy, Maxime; Cohen, Jonathan H.; De La Torre, Pedro R.; Nornes, Stein M.; Singh, Hanumant; Sørensen, Asgeir J.; Daase, Malin; Johnsen, Geir

2018-01-01

Light is a major cue for nearly all life on Earth. However, most of our knowledge concerning the importance of light is based on organisms’ response to light during daytime, including the dusk and dawn phase. When it is dark, light is most often considered as pollution, with increasing appreciation of its negative ecological effects. Using an Autonomous Surface Vehicle fitted with a hyperspectral irradiance sensor and an acoustic profiler, we detected and quantified the behavior of zooplankton in an unpolluted light environment in the high Arctic polar night and compared the results with that from a light-polluted environment close to our research vessels. First, in environments free of light pollution, the zooplankton community is intimately connected to the ambient light regime and performs synchronized diel vertical migrations in the upper 30 m despite the sun never rising above the horizon. Second, the vast majority of the pelagic community exhibits a strong light-escape response in the presence of artificial light, observed down to 100 m. We conclude that artificial light from traditional sampling platforms affects the zooplankton community to a degree where it is impossible to examine its abundance and natural rhythms within the upper 100 m. This study underscores the need to adjust sampling platforms, particularly in dim-light conditions, to capture relevant physical and biological data for ecological studies. It also highlights a previously unchartered susceptibility to light pollution in a region destined to see significant changes in light climate due to a reduced ice cover and an increased anthropogenic activity. PMID:29326985

Thin film application device and method for coating small aperture vacuum vessels

DOEpatents

Walters, Dean R; Este, Grantley O

2015-01-27

A device and method for coating an inside surface of a vessel is provided. In one embodiment, a coating device comprises a power supply and a diode in electrical communication with the power supply, wherein electrodes comprising the diode reside completely within the vessel. The method comprises reversibly sealing electrodes in a vessel, sputtering elemental metal or metal compound on the surface while maintaining the surface in a controlled atmosphere.

Heterogeneous Teams of Autonomous Vehicles: Advanced Sensing & Control

DTIC Science & Technology

2009-03-01

Final Technical 3. DATES COVERED (From To) 7/1/05-12/31708 4. TITLE AND SUBTITLE Heterogeneous Teams of Autonomous Vehicles Advanced Sensing...assimilating data from underwater and surface autonomous vehicles in addition to the usual sources of Eulerian and Lagrangian systems into a small scale

Widespread cardiovascular autonomic dysfunction in primary amyloidosis: does spontaneous hyperventilation have a compensatory role against postural hypotension?

PubMed Central

Bernardi, L; Passino, C; Porta, C; Anesi, E; Palladini, G; Merlini, G

2002-01-01

Objective: To investigate the possible causes of abnormal blood pressure control in light chain related (primary, AL) amyloidosis. Design: Cardiovascular, autonomic, and respiratory response to passive tilting were investigated in 51 patients with primary amyloidosis (mean (SEM) age 56 (2) years) and in 20 age matched controls. Spontaneous fluctuations in RR interval, respiration, end tidal carbon dioxide, blood pressure, and skin microcirculation were recorded during supine rest and with tilting. The values were subjected to spectral analysis to assess baroreflex sensitivity and the autonomic modulation of cardiac and vascular responses. Setting: Tertiary referral centre. Results: Autonomic modulation of the heart and blood pressure was nearly absent in the patients with amyloidosis: thus baroreflex sensitivity and the low frequency (0.1 Hz) fluctuations in all cardiovascular signals were severely reduced (p < 0.01 or more), as were respiratory fluctuations in the RR interval, and no change was observed upon tilting. Despite reduced autonomic modulation, blood pressure remained relatively stable in the amyloid group from supine to tilting. End tidal carbon dioxide was reduced in the amyloid patients (p < 0.001) indicating persistent hyperventilation; the breathing rate correlated inversely with the fall in blood pressure on tilting (p < 0.05). Conclusions: In primary amyloidosis, pronounced abnormalities in arterial baroreflexes and cardiovascular autonomic modulation to the heart and the vessels may be partly compensated for by hyperventilation at a slow breathing rate. PMID:12433892

Wireless Metal Detection and Surface Coverage Sensing for All-Surface Induction Heating

PubMed Central

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

2016-01-01

All-surface induction heating systems, typically comprising small-area coils, face a major challenge in detecting the presence of a metallic vessel and identifying its partial surface coverage over the coils to determine which of the coils to power up. The difficulty arises due to the fact that the user can heat vessels made of a wide variety of metals (and their alloys). To address this problem, we propose and demonstrate a new wireless detection methodology that allows for detecting the presence of metallic vessels together with uniquely sensing their surface coverages while also identifying their effective material type in all-surface induction heating systems. The proposed method is based on telemetrically measuring simultaneously inductance and resistance of the induction coil coupled with the vessel in the heating system. Here, variations in the inductance and resistance values for an all-surface heating coil loaded by vessels (made of stainless steel and aluminum) at different positions were systematically investigated at different frequencies. Results show that, independent of the metal material type, unique identification of the surface coverage is possible at all freqeuncies. Additionally, using the magnitude and phase information extracted from the coupled coil impedance, unique identification of the vessel effective material is also achievable, this time independent of its surface coverage. PMID:26978367

A new formation control of multiple underactuated surface vessels

NASA Astrophysics Data System (ADS)

Xie, Wenjing; Ma, Baoli; Fernando, Tyrone; Iu, Herbert Ho-Ching

2018-05-01

This work investigates a new formation control problem of multiple underactuated surface vessels. The controller design is based on input-output linearisation technique, graph theory, consensus idea and some nonlinear tools. The proposed smooth time-varying distributed control law guarantees that the multiple underactuated surface vessels globally exponentially converge to some desired geometric shape, which is especially centred at the initial average position of vessels. Furthermore, the stability analysis of zero dynamics proves that the orientations of vessels tend to some constants that are dependent on the initial values of vessels, and the velocities and control inputs of the vessels decay to zero. All the results are obtained under the communication scenarios of static directed balanced graph with a spanning tree. Effectiveness of the proposed distributed control scheme is demonstrated using a simulation example.

Autonomous navigation and obstacle avoidance for unmanned surface vehicles

NASA Astrophysics Data System (ADS)

Larson, Jacoby; Bruch, Michael; Ebken, John

2006-05-01

The US Navy and other Department of Defense (DoD) and Department of Homeland Security (DHS) organizations are increasingly interested in the use of unmanned surface vehicles (USVs) for a variety of missions and applications. In order for USVs to fill these roles, they must be capable of a relatively high degree of autonomous navigation. Space and Naval Warfare Systems Center, San Diego is developing core technologies required for robust USV operation in a real-world environment, primarily focusing on autonomous navigation, obstacle avoidance, and path planning.

FlyCap: Markerless Motion Capture Using Multiple Autonomous Flying Cameras.

PubMed

Xu, Lan; Liu, Yebin; Cheng, Wei; Guo, Kaiwen; Zhou, Guyue; Dai, Qionghai; Fang, Lu

2017-07-18

Aiming at automatic, convenient and non-instrusive motion capture, this paper presents a new generation markerless motion capture technique, the FlyCap system, to capture surface motions of moving characters using multiple autonomous flying cameras (autonomous unmanned aerial vehicles(UAVs) each integrated with an RGBD video camera). During data capture, three cooperative flying cameras automatically track and follow the moving target who performs large-scale motions in a wide space. We propose a novel non-rigid surface registration method to track and fuse the depth of the three flying cameras for surface motion tracking of the moving target, and simultaneously calculate the pose of each flying camera. We leverage the using of visual-odometry information provided by the UAV platform, and formulate the surface tracking problem in a non-linear objective function that can be linearized and effectively minimized through a Gaussian-Newton method. Quantitative and qualitative experimental results demonstrate the plausible surface and motion reconstruction results.

Method and apparatus for detecting irregularities on or in the wall of a vessel

DOEpatents

Bowling, Michael Keith

2000-09-12

A method of detecting irregularities on or in the wall of a vessel by detecting localized spatial temperature differentials on the wall surface, comprising scanning the vessel surface with a thermal imaging camera and recording the position of the or each region for which the thermal image from the camera is indicative of such a temperature differential across the region. The spatial temperature differential may be formed by bacterial growth on the vessel surface; alternatively, it may be the result of defects in the vessel wall such as thin regions or pin holes or cracks. The detection of leaks through the vessel wall may be enhanced by applying a pressure differential or a temperature differential across the vessel wall; the testing for leaks may be performed with the vessel full or empty, and from the inside or the outside.

Bim expression in endothelial cells and pericytes is essential for regression of the fetal ocular vasculature.

PubMed

Wang, Shoujian; Zaitoun, Ismail S; Johnson, Ryan P; Jamali, Nasim; Gurel, Zafer; Wintheiser, Catherine M; Strasser, Andreas; Lindner, Volkhard; Sheibani, Nader; Sorenson, Christine M

2017-01-01

Apoptosis plays a central role in developmental and pathological angiogenesis and vessel regression. Bim is a pro-apoptotic Bcl-2 family member that plays a prominent role in both developmental and pathological ocular vessel regression, and neovascularization. Endothelial cells (EC) and pericytes (PC) each play unique roles during vascular development, maintenance and regression. We recently showed that germline deletion of Bim results in persistent hyaloid vasculature, increased retinal vascular density and prevents retinal vessel regression in response to hyperoxia. To determine whether retinal vascular regression is attributable to Bim expression in EC or PC we generated mice carrying a conditional Bim allele (BimFlox/Flox) and VE-cadherin-cre (BimEC mice) or Pdgfrb-cre (BimPC mice). BimEC and BimPC mice demonstrated attenuated hyaloid vessel regression and postnatal retinal vascular remodeling. We also observed decreased retinal vascular apoptosis and proliferation. Unlike global Bim -/- mice, mice conditionally lacking Bim in EC or PC underwent hyperoxia-mediated vessel obliteration and subsequent retinal neovascularization during oxygen-induced ischemic retinopathy similar to control littermates. Thus, understanding the cell autonomous role Bim plays in the retinal vascular homeostasis will give us new insight into how to modulate pathological retinal neovascularization and vessel regression to preserve vision.

Containment vessel drain system

DOEpatents

Harris, Scott G.

2018-01-30

A system for draining a containment vessel may include a drain inlet located in a lower portion of the containment vessel. The containment vessel may be at least partially filled with a liquid, and the drain inlet may be located below a surface of the liquid. The system may further comprise an inlet located in an upper portion of the containment vessel. The inlet may be configured to insert pressurized gas into the containment vessel to form a pressurized region above the surface of the liquid, and the pressurized region may operate to apply a surface pressure that forces the liquid into the drain inlet. Additionally, a fluid separation device may be operatively connected to the drain inlet. The fluid separation device may be configured to separate the liquid from the pressurized gas that enters the drain inlet after the surface of the liquid falls below the drain inlet.

46 CFR 42.13-15 - Definitions of terms.

Code of Federal Regulations, 2013 CFR

2013-10-01

... line of the frame in a vessel with a metal shell and to the outer surface of the hull in a vessel with... vessel with a metal shell, and is the volume of displacement to the outer surface of the hull in a vessel... between the machinery space and peak bulkheads and continuous athwartships. When this lower deck is...

46 CFR 42.13-15 - Definitions of terms.

Code of Federal Regulations, 2012 CFR

2012-10-01

... line of the frame in a vessel with a metal shell and to the outer surface of the hull in a vessel with... vessel with a metal shell, and is the volume of displacement to the outer surface of the hull in a vessel... between the machinery space and peak bulkheads and continuous athwartships. When this lower deck is...

Autonomous Navigation Results from the Mars Exploration Rover (MER) Mission

NASA Technical Reports Server (NTRS)

Maimone, Mark; Johnson, Andrew; Cheng, Yang; Willson, Reg; Matthies, Larry H.

2004-01-01

In January, 2004, the Mars Exploration Rover (MER) mission landed two rovers, Spirit and Opportunity, on the surface of Mars. Several autonomous navigation capabilities were employed in space for the first time in this mission. ]n the Entry, Descent, and Landing (EDL) phase, both landers used a vision system called the, Descent Image Motion Estimation System (DIMES) to estimate horizontal velocity during the last 2000 meters (m) of descent, by tracking features on the ground with a downlooking camera, in order to control retro-rocket firing to reduce horizontal velocity before impact. During surface operations, the rovers navigate autonomously using stereo vision for local terrain mapping and a local, reactive planning algorithm called Grid-based Estimation of Surface Traversability Applied to Local Terrain (GESTALT) for obstacle avoidance. ]n areas of high slip, stereo vision-based visual odometry has been used to estimate rover motion, As of mid-June, Spirit had traversed 3405 m, of which 1253 m were done autonomously; Opportunity had traversed 1264 m, of which 224 m were autonomous. These results have contributed substantially to the success of the mission and paved the way for increased levels of autonomy in future missions.

Development and Characteristics of a Mobile, Semi-Autonomous Floating Platform for in situ Lake Measurements

NASA Astrophysics Data System (ADS)

Barry, D.; Lemmin, U.; Le Dantec, N.; Zulliger, L.; Rusterholz, M.; Bolay, M.; Rossier, J.; Kangur, K.

2013-12-01

In the development of sustainable management strategies of lakes more insight into their physical, chemical and ecological dynamics is needed. Field data obtained from various types of sensors with adequate spatial and temporal sampling rate are essential to understand better the processes that govern fluxes and pathways of water masses and transported compounds, whether for model validation or for monitoring purposes. One advantage of unmanned platforms is that they limit the disturbances typically affecting the quality of data collected on small vessels, including perturbations caused by movements of onboard crew. We have developed a mobile, semi-autonomous floating platform with 8 h power autonomy using a 5 m long by 2.5 m wide catamaran. Our approach focused on modularity and high payload capacity in order to accommodate a large number of sensors both in terms of electronic (power and data) and mechanical constraints of integration. Software architecture and onboard electronics use National Instruments technology to simplify and standardize integration of sensors, actuators and communication. Piecewise-movable deck sections allow optimizing platform stability depending on the payload. The entire system is controlled by a remote computer located on an accompanying vessel and connected via a wireless link with a range of over 1 km. Real-time transmission of GPS-stamped measurements allows immediate modifications in the survey plan if needed. The displacement of the platform is semi-autonomous, with the options of either autopilot mode following a pre-planned course specified by waypoints or remote manual control from the accompanying vessel. Maintenance of permanent control over the platform displacement is required for safety reasons with respect to other users of the lake. Currently, the sensor payload comprises an array of fast temperature probes, a bottom-tracking ADCP and atmospheric sensors including a radiometer. A towed CTD with additional water quality sensors operated from a remotely controlled winch is presently being integrated. Field tests have shown that the platform is reliable, capable of collecting long transects of 2D lake and collocated atmospheric boundary layer data and adaptable to integrate new sensors.

An Analytical Thermal Model for Autonomous Soaring Research

NASA Technical Reports Server (NTRS)

Allen, Michael

2006-01-01

A viewgraph presentation describing an analytical thermal model used to enable research on autonomous soaring for a small UAV aircraft is given. The topics include: 1) Purpose; 2) Approach; 3) SURFRAD Data; 4) Convective Layer Thickness; 5) Surface Heat Budget; 6) Surface Virtual Potential Temperature Flux; 7) Convective Scaling Velocity; 8) Other Calculations; 9) Yearly trends; 10) Scale Factors; 11) Scale Factor Test Matrix; 12) Statistical Model; 13) Updraft Strength Calculation; 14) Updraft Diameter; 15) Updraft Shape; 16) Smoothed Updraft Shape; 17) Updraft Spacing; 18) Environment Sink; 19) Updraft Lifespan; 20) Autonomous Soaring Research; 21) Planned Flight Test; and 22) Mixing Ratio.

Mixed-methods analytic approach for determining potential impacts of vessel noise on sperm whale click behavior.

PubMed

Azzara, Alyson J; von Zharen, Wyndylyn M; Newcomb, Joal J

2013-12-01

The Gulf of Mexico is a center of marine activities from seismic exploration to shipping, drilling, platform installation, lightering, and construction, among others. This analysis explored whether sperm whales respond to the passage of vessels using changes in total number of clicks during vessel passages as a proxy for potential variation in behavior. The data for this analysis were collected in 2001 as part of a larger Littoral Acoustic Demonstration Center project using the Environmental Acoustics Recording System buoys. These buoys were bottom moored, autonomous, and self-recording systems consisting of an omni-directional hydrophone and instrument package. Data from 36 days of continuous acoustic monitoring were recorded at a sampling rate of 11.725 kHz, and produced reliable recordings from 5 Hz to ∼5.8 kHz. Multiple preparatory steps were executed including calibration of an automatic click detector. Results indicate a significant decrease (32%) in the number of clicks detected as a ship approached an area. There were also significantly fewer clicks detected after the vessel passed than before (23%).

Lunar far side surface navigation using Linked Autonomous Interplanetary Satellite Orbit Navigation (LiAISON)

NASA Astrophysics Data System (ADS)

Hesar, Siamak G.; Parker, Jeffrey S.; Leonard, Jason M.; McGranaghan, Ryan M.; Born, George H.

2015-12-01

We study the application of Linked Autonomous Interplanetary Satellite Orbit Navigation (LiAISON) to track vehicles on the far side of the lunar surface. The LiAISON architecture is demonstrated to achieve accurate orbit determination solutions for various mission scenarios in the Earth-Moon system. Given the proper description of the force field, LiAISON is capable of producing absolute orbit determination solutions using relative satellite-to-satellite tracking observations alone. The lack of direct communication between Earth-based tracking stations and the far side of the Moon provides an ideal opportunity for implementing LiAISON. This paper presents a novel approach to use the LiAISON architecture to perform autonomous navigation of assets on the lunar far side surface. Relative measurements between a spacecraft placed in an EML-2 halo orbit and lunar surface asset(s) are simulated and processed. Comprehensive simulation results show that absolute states of the surface assets are observable with an achieved accuracy of the position estimate on the order of tens of meters.

In Situ Surveying of Saturn's Rings

NASA Technical Reports Server (NTRS)

Clark, P. E.; Curtis, S. A.; Rilee, M. L.; Cheung, C.

2004-01-01

The Saturn Autonomous Ring Array (SARA) mission concept is a new application for the Autonomous Nano-Technology Swarm (ANTS) architecture, a paradigm being developed for exploration of high surface area and/or multibody targets to minimize costs and maximize effectiveness of survey operations. Systems designed with ANTS architecture are built from potentially very large numbers of highly autonomous, yet socially interactive, specialists, in approximately ten specialist classes. Here, we analyze requirements for such a mission as well as specialized autonomous operations which would support this application.

Relationships of Hardiness to Physical and Mental Health Status in Military Men: A Test of Mediated Effects

DTIC Science & Technology

2013-01-01

physiological changes. Acute autonomic nervous system changes, for example, include innervation of the heart, blood vessels, and adrenal glands by...Fardella, C. E., & Kalergis, A. M. (2011). Aldosterone as a modulator of immunity: Implications in the organ damage. Journal of Hypertension... aldosterone on cardiometabolic syndrome. International Journal of Hyperten- sion, 685238, 1–8. Stuart-Hamilton, I. (2007). Dictionary of psychological

Towards a Possible Therapy for Diabetes Complications

DTIC Science & Technology

2011-10-01

diabetes, most T1D patients gradually develop one or several histopathological lesions affecting the vasculature of both large and small blood vessels...within 5-10 years of T1D. Other forms include cranial and peripheral motor neuropathies and autonomic neuropathies affecting gastric and intestinal...significantly decreased caspase-3 levels and activity and upregulated production of the anti- apoptotic factor B cell CLL/ lymphoma 2 (BCL-2). Glucose

Investigating plume dynamics at the ocean-glacier interface with turbulence profiling and autonomous vessels

NASA Astrophysics Data System (ADS)

Jackson, R. H.; Nash, J. D.; Sutherland, D. A.; Amundson, J. M.; Kienholz, C.; Skyllingstad, E. D.; Motyka, R. J.

2017-12-01

The exchanges of heat and freshwater at tidewater glacier termini are modulated by small-scale turbulent processes. However, few observations have been obtained near the ocean-glacier interface, limiting our ability to quantify turbulent fluxes or test melt parameterizations in ocean-glacier models. Here, we explore the turbulent plume dynamics at LeConte Glacier, Alaska with three extensive field campaigns in May, August and September (2016-17). Two autonomous vessels collected repeat transects of velocity and water properties near the glacier, often within 20 m of the terminus. Concurrent shipboard surveying measured turbulence with a vertical microstructure profiler, along with water properties and velocity. These high-resolution surveys provide a 3D view of the circulation and allow us to quantify turbulent fluxes in the near-glacier region. We observe two regimes at the terminus: an energetic upwelling plume driven by subglacial discharge at a persistent location, and submarine melt-driven convection along other parts of the terminus. We trace the evolution of the subglacial discharge plume as it flows away from the glacier, from an initial stage of vigorous mixing to a more quiescent outflow downstream. Resolving these spatial patterns of upwelling and mixing near glaciers is a key step towards understanding submarine melt rates and glacial fjord circulation.

Translational neurocardiology: preclinical models and cardioneural integrative aspects

PubMed Central

Andresen, M. C.; Armour, J. A.; Billman, G. E.; Chen, P.‐S.; Foreman, R. D.; Herring, N.; O'Leary, D. S.; Sabbah, H. N.; Schultz, H. D.; Sunagawa, K.; Zucker, I. H.

2016-01-01

Abstract Neuronal elements distributed throughout the cardiac nervous system, from the level of the insular cortex to the intrinsic cardiac nervous system, are in constant communication with one another to ensure that cardiac output matches the dynamic process of regional blood flow demand. Neural elements in their various ‘levels’ become differentially recruited in the transduction of sensory inputs arising from the heart, major vessels, other visceral organs and somatic structures to optimize neuronal coordination of regional cardiac function. This White Paper will review the relevant aspects of the structural and functional organization for autonomic control of the heart in normal conditions, how these systems remodel/adapt during cardiac disease, and finally how such knowledge can be leveraged in the evolving realm of autonomic regulation therapy for cardiac therapeutics. PMID:27098459

Evolution of Autonomous Self-Righting Behaviors for Articulated Nanorovers

NASA Technical Reports Server (NTRS)

Tunstel, Edward

1999-01-01

Miniature rovers with articulated mobility mechanisms are being developed for planetary surface exploration on Mars and small solar system bodies. These vehicles are designed to be capable of autonomous recovery from overturning during surface operations. This paper describes a computational means of developing motion behaviors that achieve the autonomous recovery function. It proposes a control software design approach aimed at reducing the effort involved in developing self-righting behaviors. The approach is based on the integration of evolutionary computing with a dynamics simulation environment for evolving and evaluating motion behaviors. The automated behavior design approach is outlined and its underlying genetic programming infrastructure is described.

Flattening maps for the visualization of multibranched vessels.

PubMed

Zhu, Lei; Haker, Steven; Tannenbaum, Allen

2005-02-01

In this paper, we present two novel algorithms which produce flattened visualizations of branched physiological surfaces, such as vessels. The first approach is a conformal mapping algorithm based on the minimization of two Dirichlet functionals. From a triangulated representation of vessel surfaces, we show how the algorithm can be implemented using a finite element technique. The second method is an algorithm which adjusts the conformal mapping to produce a flattened representation of the original surface while preserving areas. This approach employs the theory of optimal mass transport. Furthermore, a new way of extracting center lines for vessel fly-throughs is provided.

Flattening Maps for the Visualization of Multibranched Vessels

PubMed Central

Zhu, Lei; Haker, Steven; Tannenbaum, Allen

2013-01-01

In this paper, we present two novel algorithms which produce flattened visualizations of branched physiological surfaces, such as vessels. The first approach is a conformal mapping algorithm based on the minimization of two Dirichlet functionals. From a triangulated representation of vessel surfaces, we show how the algorithm can be implemented using a finite element technique. The second method is an algorithm which adjusts the conformal mapping to produce a flattened representation of the original surface while preserving areas. This approach employs the theory of optimal mass transport. Furthermore, a new way of extracting center lines for vessel fly-throughs is provided. PMID:15707245

Tubular inverse opal scaffolds for biomimetic vessels

NASA Astrophysics Data System (ADS)

Zhao, Ze; Wang, Jie; Lu, Jie; Yu, Yunru; Fu, Fanfan; Wang, Huan; Liu, Yuxiao; Zhao, Yuanjin; Gu, Zhongze

2016-07-01

There is a clinical need for tissue-engineered blood vessels that can be used to replace or bypass damaged arteries. The success of such grafts depends strongly on their ability to mimic native arteries; however, currently available artificial vessels are restricted by their complex processing, controversial integrity, or uncontrollable cell location and orientation. Here, we present new tubular scaffolds with specific surface microstructures for structural vessel mimicry. The tubular scaffolds are fabricated by rotationally expanding three-dimensional tubular inverse opals that are replicated from colloidal crystal templates in capillaries. Because of the ordered porous structure of the inverse opals, the expanded tubular scaffolds are imparted with circumferentially oriented elliptical pattern microstructures on their surfaces. It is demonstrated that these tailored tubular scaffolds can effectively make endothelial cells to form an integrated hollow tubular structure on their inner surface and induce smooth muscle cells to form a circumferential orientation on their outer surface. These features of our tubular scaffolds make them highly promising for the construction of biomimetic blood vessels.There is a clinical need for tissue-engineered blood vessels that can be used to replace or bypass damaged arteries. The success of such grafts depends strongly on their ability to mimic native arteries; however, currently available artificial vessels are restricted by their complex processing, controversial integrity, or uncontrollable cell location and orientation. Here, we present new tubular scaffolds with specific surface microstructures for structural vessel mimicry. The tubular scaffolds are fabricated by rotationally expanding three-dimensional tubular inverse opals that are replicated from colloidal crystal templates in capillaries. Because of the ordered porous structure of the inverse opals, the expanded tubular scaffolds are imparted with circumferentially oriented elliptical pattern microstructures on their surfaces. It is demonstrated that these tailored tubular scaffolds can effectively make endothelial cells to form an integrated hollow tubular structure on their inner surface and induce smooth muscle cells to form a circumferential orientation on their outer surface. These features of our tubular scaffolds make them highly promising for the construction of biomimetic blood vessels. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr03173k

Two-Phase Thermal Switching System for a Small, Extended Duration Lunar Surface Science Platform

NASA Technical Reports Server (NTRS)

Bugby, David C.; Farmer, Jeffery T.; OConnor, Brian F.; Wirzburger, Melissa J.; Abel, Elisabeth D.; Stouffer, Chuck J.

2010-01-01

This paper describes a novel thermal control system for the Warm Electronics Box (WEB) on board a small lunar surface lander intended to support science activities anywhere on the lunar surface for an extended duration of up to 6 years. Virtually all lander electronics, which collectively dissipate about 60 W in the reference mission, are contained within the WEB. These devices must be maintained below 323 K (with a goal of 303 K) during the nearly 15-earth-day lunar day, when surface temperatures can reach 390K, and above 263 K during the nearly 15-earth-day lunar night, when surface temperatures can reach 100K. Because of the large temperature swing from lunar day-to-night, a novel thermal switching system was required that would be able to provide high conductance from WEB to radiator(s) during the hot lunar day and low (or negligible) conductance during the cold lunar night. The concept that was developed consists of ammonia variable conductance heat pipes (VCHPs) to collect heat from WEB components and a polymer wick propylene loop heat pipe (LHP) to transport the collected heat to the radiator(s). The VCHPs autonomously maximize transport when the WEB is warm and autonomously shut down when the WEB gets cold. The LHP autonomously shuts down when the VCHPs shut down. When the environment transitions from lunar night to day, the VCHPs and LHP autonomously turn back on. Out of 26 analyzed systems, this novel arrangement was able to best achieve the combined goals of zero control power, autonomous operation, long life, low complexity, low T, and landed tilt tolerance.

[Analysis of heat transfer in the biological tissue layer with distributed system of blood vessels].

PubMed

Bogatov, N M; Pelipenko, O N

2005-09-01

Processes of heat transfer in the skin layer with blood vessels were investigated using mathematical modeling. Analysis of influence of a pathological state of blood vessels on heterogeneity of thermal field of the skin surface was carried out. For each site of body surface, there is a certain difference of temperature between normal and pathological sites, being specific for differential diagnosis of diseases of dermal and hypodermic vessels.

Predictive simulation of bidirectional Glenn shunt using a hybrid blood vessel model.

PubMed

Li, Hao; Leow, Wee Kheng; Chiu, Ing-Sh

2009-01-01

This paper proposes a method for performing predictive simulation of cardiac surgery. It applies a hybrid approach to model the deformation of blood vessels. The hybrid blood vessel model consists of a reference Cosserat rod and a surface mesh. The reference Cosserat rod models the blood vessel's global bending, stretching, twisting and shearing in a physically correct manner, and the surface mesh models the surface details of the blood vessel. In this way, the deformation of blood vessels can be computed efficiently and accurately. Our predictive simulation system can produce complex surgical results given a small amount of user inputs. It allows the surgeon to easily explore various surgical options and evaluate them. Tests of the system using bidirectional Glenn shunt (BDG) as an application example show that the results produc by the system are similar to real surgical results.

Advances in Shallow-Water, High-Resolution Seafloor Mapping: Integrating an Autonomous Surface Vessel (ASV) Into Nearshore Geophysical Studies

NASA Astrophysics Data System (ADS)

Denny, J. F.; O'Brien, T. F.; Bergeron, E.; Twichell, D.; Worley, C. R.; Danforth, W. W.; Andrews, B. A.; Irwin, B.

2006-12-01

The U.S. Geological Survey (USGS) has been heavily involved in geological mapping of the seafloor since the 1970s. Early mapping efforts such as GLORIA provided broad-scale imagery of deep waters (depths > 400 meters) within the Exclusive Economic Zone (EEZ). In the early 1990's, the USGS research emphasis shifted from deep- to shallow-water environments (inner continental shelf, nearshore, estuaries) to address pertinent coastal issues such as erosion, sediment availability, sediment transport, vulnerability of coastal areas to natural and anthropogenic hazards, and resource management. Geologic framework mapping in these shallow- water environments has provided valuable data used to 1) define modern sediment distribution and thickness, 2) determine underlying stratigraphic and structural controls on shoreline behavior, and 3) enable onshore-to- offshore geologic mapping within the coastal zone when coupled with subaerial techniques such as GPR and topographic LIDAR. Research in nearshore areas presents technological challenges due to the dynamics of the environment, high volume of data collected, and the geophysical limitations of operating in very shallow water. In 2004, the USGS, in collaboration with NOAA's Coastal Services Center, began a multi-year seafloor mapping effort to better define oyster habitats within Apalachicola Bay, Florida, a shallow water estuary along the northern Gulf of Mexico. The bay poses a technological challenge due to its shallow depths (< 4-m) and high turbidity that prohibits the use of bathymetric LIDAR. To address this extreme shallow water setting, the USGS incorporated an Autonomous Surface Vessel (ASV) into seafloor mapping operations, in June 2006. The ASV is configured with a chirp sub-bottom profiler (4 24 kHz), dual-frequency chirp sidescan-sonar (100/500 kHz), single-beam echosounder (235 kHz), and forward-looking digital camera, and will be used to delineate the distribution and thickness of surficial sediment, presence of oyster beds, and sea bed morphology in water depths less than 5-m. The ASV is a catamaran-based platform, 10 feet in length, 4 feet in width, and approximately 260 lbs in weight. The vehicle is operated remotely through a wireless modem network enabling real-time monitoring of data acquisition. The ASV is navigated using RTK, and heave, pitch and roll are recorded with onboard motion sensors. Additional sensors, such as ADCPs, can also be housed within the vehicle. The ASV is able to operate in previously inaccessible areas, and will not only augment existing shallow-water research capabilities, but will also improve our understanding of the geologic controls to modern beach behavior and coastal evolution.

AURORA BOREALIS - European Research Icebreaker With Drilling Capability

NASA Astrophysics Data System (ADS)

Biebow, N.; Lembke-Jene, L.; Kunz-Pirrung, M.; Thiede, J.

2008-12-01

The polar oceans are the least known areas of the globe, in although they hold the key to many of our climate´s secrets. How does the sea ice coverage and the sea water properties change? How do plants and animals survive under the most extreme conditions of the earth? Which information of past climate change can be read from the sediments at the sea-floor and how can the future changing climate be predicted? In order to answer such and further questions, for the moment a hypermodern research vessel, the AURORA BOREALIS, is planned, which can handle the cool summers and freezing winters of the polar oceans and which can drill deep into the sea floor. AURORA BOREALIS will be the most advanced Research Icebreaker in the world with a multi-functional role of drilling in deep ocean basins and supporting climate/environmental research and decision support for stakeholder governments for the next 35-40 years. It will have a high icebreaking capacity to penetrate autonomously (single ship operation) into the central Arctic Ocean with more than 2.5 meters of ice cover, during all seasons of the year. The new technological features will include dynamic positioning in closed sea- ice cover, satellite navigation and ice-management support and the deployment and operation of Remotely Operated Vehicles (ROV) and Autonomous Underwater Vehicles (AUVs) from the twin moon-pools. A unique feature of the vessel is the deep-sea drilling rig, which will enable sampling of the ocean floor and sub-sea up to 5000 m water and 1000 m penetration at the most inhospitable places on earth. The drilling capability will be deployed in both Polar Regions on the long run and AURORA BOREALIS will be the only vessel worldwide that could undertake this type of scientific investigation.

MER Surface Phase; Blurring the Line Between Fault Protection and What is Supposed to Happen

NASA Technical Reports Server (NTRS)

Reeves, Glenn E.

2008-01-01

An assessment on the limitations of communication with MER rovers and how such constraints drove the system design, flight software and fault protection architecture, blurring the line between traditional fault protection and expected nominal behavior, and requiring the most novel autonomous and semi-autonomous elements of the vehicle software including communication, surface mobility, attitude knowledge acquisition, fault protection, and the activity arbitration service.

Tier-scalable reconnaissance: the future in autonomous C4ISR systems has arrived: progress towards an outdoor testbed

NASA Astrophysics Data System (ADS)

Fink, Wolfgang; Brooks, Alexander J.-W.; Tarbell, Mark A.; Dohm, James M.

2017-05-01

Autonomous reconnaissance missions are called for in extreme environments, as well as in potentially hazardous (e.g., the theatre, disaster-stricken areas, etc.) or inaccessible operational areas (e.g., planetary surfaces, space). Such future missions will require increasing degrees of operational autonomy, especially when following up on transient events. Operational autonomy encompasses: (1) Automatic characterization of operational areas from different vantages (i.e., spaceborne, airborne, surface, subsurface); (2) automatic sensor deployment and data gathering; (3) automatic feature extraction including anomaly detection and region-of-interest identification; (4) automatic target prediction and prioritization; (5) and subsequent automatic (re-)deployment and navigation of robotic agents. This paper reports on progress towards several aspects of autonomous C4ISR systems, including: Caltech-patented and NASA award-winning multi-tiered mission paradigm, robotic platform development (air, ground, water-based), robotic behavior motifs as the building blocks for autonomous tele-commanding, and autonomous decision making based on a Caltech-patented framework comprising sensor-data-fusion (feature-vectors), anomaly detection (clustering and principal component analysis), and target prioritization (hypothetical probing).

Autonomous Research Vessels for Adaptive Upper-Ocean Process Studies

DTIC Science & Technology

2014-09-30

system with the goal  of extending  its mission robustness,  adaptabilit and science capabilities beyond that  of the   Arduino -­‐ based ones... measure the interplay between these finescale dynamics and turbulence, which ultimately drives  the  irreversible  heat/freshwater  transports...profiling in Greenland  Fjords. acquiring CTD cast (and ADCP profiles) within m of a Greenland iceberg.APPROACH: Our first ARV (ARV Rob) was based on

Simulation of the communication system between an AUV group and a surface station

NASA Astrophysics Data System (ADS)

Burtovaya, D.; Demin, A.; Demeshko, M.; Moiseev, A.; Kudryashova, A.

2017-01-01

An object model for simulation of the communications system of an autonomous underwater vehicles (AUV) group with a surface station is proposed in the paper. Implementation of the model is made on the basis of the software package “Object Distribution Simulation”. All structural relationships and behavior details are described. The application was developed on the basis of the proposed model and is now used for computational experiments on the simulation of the communications system between the autonomous underwater vehicles group and a surface station.

Research Vessel Meteorological and Oceanographic Systems Support Satellite and Model Validation Studies

NASA Astrophysics Data System (ADS)

Smith, S. R.; Lopez, N.; Bourassa, M. A.; Rolph, J.; Briggs, K.

2012-12-01

The research vessel data center at the Florida State University routinely acquires, quality controls, and distributes underway surface meteorological and oceanographic observations from vessels. The activities of the center are coordinated by the Shipboard Automated Meteorological and Oceanographic System (SAMOS) initiative in partnership with the Rolling Deck to Repository (R2R) project. The data center evaluates the quality of the observations, collects essential metadata, provides data quality feedback to vessel operators, and ensures the long-term data preservation at the National Oceanographic Data Center. A description of the SAMOS data stewardship protocols will be provided, including dynamic web tools that ensure users can select the highest quality observations from over 30 vessels presently recruited to the SAMOS initiative. Research vessels provide underway observations at high-temporal frequency (1 min. sampling interval) that include navigational (position, course, heading, and speed), meteorological (air temperature, humidity, wind, surface pressure, radiation, rainfall), and oceanographic (surface sea temperature and salinity) samples. Recruited vessels collect a high concentration of data within the U.S. continental shelf and also frequently operate well outside routine shipping lanes, capturing observations in extreme ocean environments (Southern Ocean, Arctic, South Atlantic and Pacific). The unique quality and sampling locations of research vessel observations and there independence from many models and products (RV data are rarely distributed via normal marine weather reports) makes them ideal for validation studies. We will present comparisons between research vessel observations and model estimates of the sea surface temperature and salinity in the Gulf of Mexico. The analysis reveals an underestimation of the freshwater input to the Gulf from rivers, resulting in an overestimation of near coastal salinity in the model. Additional comparisons between surface atmospheric products derived from satellite observations and the underway research vessel observations will be shown. The strengths and limitations of research observations for validation studies will be highlighted through these case studies.

Tubular inverse opal scaffolds for biomimetic vessels.

PubMed

Zhao, Ze; Wang, Jie; Lu, Jie; Yu, Yunru; Fu, Fanfan; Wang, Huan; Liu, Yuxiao; Zhao, Yuanjin; Gu, Zhongze

2016-07-14

There is a clinical need for tissue-engineered blood vessels that can be used to replace or bypass damaged arteries. The success of such grafts depends strongly on their ability to mimic native arteries; however, currently available artificial vessels are restricted by their complex processing, controversial integrity, or uncontrollable cell location and orientation. Here, we present new tubular scaffolds with specific surface microstructures for structural vessel mimicry. The tubular scaffolds are fabricated by rotationally expanding three-dimensional tubular inverse opals that are replicated from colloidal crystal templates in capillaries. Because of the ordered porous structure of the inverse opals, the expanded tubular scaffolds are imparted with circumferentially oriented elliptical pattern microstructures on their surfaces. It is demonstrated that these tailored tubular scaffolds can effectively make endothelial cells to form an integrated hollow tubular structure on their inner surface and induce smooth muscle cells to form a circumferential orientation on their outer surface. These features of our tubular scaffolds make them highly promising for the construction of biomimetic blood vessels.

Translational neurocardiology: preclinical models and cardioneural integrative aspects.

PubMed

Ardell, J L; Andresen, M C; Armour, J A; Billman, G E; Chen, P-S; Foreman, R D; Herring, N; O'Leary, D S; Sabbah, H N; Schultz, H D; Sunagawa, K; Zucker, I H

2016-07-15

Neuronal elements distributed throughout the cardiac nervous system, from the level of the insular cortex to the intrinsic cardiac nervous system, are in constant communication with one another to ensure that cardiac output matches the dynamic process of regional blood flow demand. Neural elements in their various 'levels' become differentially recruited in the transduction of sensory inputs arising from the heart, major vessels, other visceral organs and somatic structures to optimize neuronal coordination of regional cardiac function. This White Paper will review the relevant aspects of the structural and functional organization for autonomic control of the heart in normal conditions, how these systems remodel/adapt during cardiac disease, and finally how such knowledge can be leveraged in the evolving realm of autonomic regulation therapy for cardiac therapeutics. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

Cooling water distribution system

DOEpatents

Orr, Richard

1994-01-01

A passive containment cooling system for a nuclear reactor containment vessel. Disclosed is a cooling water distribution system for introducing cooling water by gravity uniformly over the outer surface of a steel containment vessel using an interconnected series of radial guide elements, a plurality of circumferential collector elements and collector boxes to collect and feed the cooling water into distribution channels extending along the curved surface of the steel containment vessel. The cooling water is uniformly distributed over the curved surface by a plurality of weirs in the distribution channels.

Gas reservoir and a method to supply gas to plasma tubes

DOEpatents

Stautner, Ernst Wolfgang; Michael, Joseph Darryl

2017-01-31

A reservoir for storing and supplying a portion of a reservoir gas into a gas-filled tube is presented. The reservoir includes a first vessel having a thermally conductive surface, a meshed vessel having a lid, and placed inside the first vessel to form a cavity between the meshed vessel and the first vessel, at least one tray placed inside the meshed vessel to divide an inner space of the meshed vessel into a plurality of compartments, a sorbent material placed inside the plurality of compartments in the meshed vessel, a temperature control device positioned such that a first portion of the temperature control device is in physical contact with at least a portion of the thermally conductive surface, and a change in the temperature of the temperature control device changes the temperature of the sorbent material, wherein the reservoir gas is retained by the sorbent material at the storage temperature.

Gross anatomical study on the human myocardial bridges with special reference to the spatial relationship among coronary arteries, cardiac veins, and autonomic nerves.

PubMed

Watanabe, Yuko; Arakawa, Takamitsu; Kageyama, Ikuo; Aizawa, Yukio; Kumaki, Katsuji; Miki, Akinori; Terashima, Toshio

2016-04-01

Coronary arteries are frequently covered by cardiac muscles. This arrangement is termed a myocardial bridge. Previous studies have shown that myocardial bridges can cause myocardial ischemic diseases or cardiac arrhythmia, but the relevant pathogenic mechanisms remain unknown. We examined 60 hearts from Japanese cadavers macroscopically to clarify the spatial relationships among coronary arteries, cardiac veins and autonomic nerves. We found 86 myocardial bridges in 47 hearts from the 60 cadavers examined (78.3%). Next, we dissected out nine hearts with myocardial bridges in detail under the operating microscope. We found no additional branches of coronary arteries on the myocardial bridge surfaces. However, the cardiac veins, which usually accompany the coronary arteries, ran independently on the myocardial bridge surfaces in the same region. Cardiac autonomic nerves comprised two rami: one was associated with the coronary artery under the myocardial bridge and the other ran on the surface of the bridge. Such spatial relationships among the coronary arteries, cardiac veins and cardiac autonomic nerves at the myocardial bridges are quite similar to those in mouse embryo hearts. © 2015 Wiley Periodicals, Inc.

Vector Sky Glint Corrections for Above Surface Retrieval of the Subsurface Polarized Light Field

NASA Astrophysics Data System (ADS)

Gilerson, A.; Foster, R.; McGilloway, A.; Ibrahim, A.; El-habashi, A.; Carrizo, C.; Ahmed, S.

2016-02-01

Knowledge of the underwater light field is fundamental to determining the health of the world's oceans and coastal regions. For decades, traditional remote sensing retrieval methods that rely solely on the spectral intensity of the water-leaving light have provided indicators of marine ecosystem health. As the demand for retrieval accuracy rises, use of the polarized nature of light as an additional remote sensing tool is becoming necessary. In order to observe the underwater polarized light field from above the surface (for ship, shore, or satellite applications), a method of correcting the above water signal for the effects of polarized surface-reflected skylight is needed. For three weeks in July-August 2014, the NASA Ship Aircraft Bio-Optical Research (SABOR) cruise continuously observed the polarized radiance of the ocean and the sky using a HyperSAS-POL system. The system autonomously tracks the Sun position and the heading of the research vessel in order to maintain a fixed relative solar azimuth angle (i.e. ±90°) and therefore avoid the specular reflection of the sunlight. Additionally, in-situ inherent optical properties (IOPs) were continuously acquired using a set of instrument packages modified for underway measurement, hyperspectral radiometric measurements were taken manually at all stations, and an underwater polarimeter was deployed when conditions permitted. All measurements, above and below the sea surface, were combined and compared in an effort to first develop a glint (sky + Sun) correction scheme for the upwelling polarized signal from a wind-driven ocean surface and compare with one assuming that the ocean surface is flat. Accurate retrieval of the subsurface vector light field is demonstrated through comparisons with polarized radiative transfer codes and direct measurements made by the underwater polarimeter.

Reactor vessel seal service fixture

DOEpatents

Ritz, W.C.

1975-12-01

An apparatus for the preparation of exposed sealing surfaces along the open rim of a nuclear reactor vessel comprised of a motorized mechanism for traveling along the rim and simultaneously brushing the exposed surfaces is described.

Body surface detection method for photoacoustic image data using cloth-simulation technique

NASA Astrophysics Data System (ADS)

Sekiguchi, H.; Yoshikawa, A.; Matsumoto, Y.; Asao, Y.; Yagi, T.; Togashi, K.; Toi, M.

2018-02-01

Photoacoustic tomography (PAT) is a novel modality that can visualize blood vessels without contrast agents. It clearly shows blood vessels near the body surface. However, these vessels obstruct the observation of deep blood vessels. As the existence range of each vessel is determined by the distance from the body surface, they can be separated if the position of the skin is known. However, skin tissue, which does not contain hemoglobin, does not appear in PAT results, therefore, manual estimation is required. As this task is very labor-intensive, its automation is highly desirable. Therefore, we developed a method to estimate the body surface using the cloth-simulation technique, which is a commonly used method to create computer graphics (CG) animations; however, it has not yet been employed for medical image processing. In cloth simulations, the virtual cloth is represented by a two-dimensional array of mass nodes. The nodes are connected with each other by springs. Once the cloth is released from a position away from the body, each node begins to move downwards under the effect of gravity, spring, and other forces; some of the nodes hit the superficial vessels and stop. The cloth position in the stationary state represents the body surface. The body surface estimation, which required approximately 1 h with the manual method, is automated and it takes only approximately 10 s with the proposed method. The proposed method could facilitate the practical use of PAT.

An LNG release, transport, and fate model system for marine spills.

PubMed

Spaulding, Malcolm L; Swanson, J Craig; Jayko, Kathy; Whittier, Nicole

2007-02-20

LNGMAP, a fully integrated, geographic information based modular system, has been developed to predict the fate and transport of marine spills of LNG. The model is organized as a discrete set of linked algorithms that represent the processes (time dependent release rate, spreading, transport on the water surface, evaporation from the water surface, transport and dispersion in the atmosphere, and, if ignited, burning and associated radiated heat fields) affecting LNG once it is released into the environment. A particle-based approach is employed in which discrete masses of LNG released from the source are modeled as individual masses of LNG or spillets. The model is designed to predict the gas mass balance as a function of time and to display the spatial and temporal evolution of the gas (and radiated energy field). LNGMAP has been validated by comparisons to predictions of models developed by ABS Consulting and Sandia for time dependent point releases from a draining tank, with and without burning. Simulations were in excellent agreement with those performed by ABS Consulting and consistent with Sandia's steady state results. To illustrate the model predictive capability for realistic emergency scenarios, simulations were performed for a tanker entering Block Island Sound. Three hypothetical cases were studied: the first assumes the vessel continues on course after the spill starts, the second that the vessel stops as soon as practical after the release begins (3 min), and the third that the vessel grounds at the closest site practical. The model shows that the areas of the surface pool and the incident thermal radiation field (with burning) are minimized and dispersed vapor cloud area (without burning) maximized if the vessel continues on course. For this case the surface pool area, with burning, is substantially smaller than for the without burning case because of the higher mass loss rate from the surface pool due to burning. Since the vessel speed substantially exceeds the spill spreading rate, both the thermal radiation fields and surface pool trail the vessel. The relative directions and speeds of the wind and vessel movement govern the orientation of the dispersed plume. If the vessel stops, the areas of the surface pool and incident radiation field (with burning) are maximized and the dispersed cloud area (without burning) minimized. The longer the delay in stopping the vessel, the smaller the peak values are for the pool area and the size of the thermal radiation field. Once the vessel stops, the spill pool is adjacent to the vessel and moving down current. The thermal radiation field is oriented similarly. These results may be particularly useful in contingency planning for underway vessels.

The Theseus Autonomous Underwater Vehicle: A Canadian Success Story

DTIC Science & Technology

1997-04-01

P502414.PDF [Page: 1 of 9] P502414.PDF [Page: 2 of 9] P502414.PDF [Page: 3 of 9] The Theseus Autonomous Underwater Vehicle A Canadian Success Story...autonomous underwater vehicle, named Theseus , for laying optical fiber cables in ice- covered waters. In trials and missions conducted in 1996, this...stations. An acoustic telemetry system enables communication with Theseus from surface stations, and an optical telemetry system is used for system

Constraining calving front processes on W Greenland outlet glaciers using inertial-corrected laser scanning & swath-bathymetry

NASA Astrophysics Data System (ADS)

Bates, R.; Hubbard, A.; Neale, M.; Woodward, J.; Box, J. E.; Nick, F.

2010-12-01

Calving and submarine melt account for the majority of loss from the Antarctic and over 50% of that from the Greenland Ice Sheet. These ice-ocean processes are highly efficient mass-loss mechanisms, providing a rapid link between terrestrial ice (storage) and the oceanic sink (sea level/freshwater flux) which renders the ocean-outlet-ice sheet system potentially highly non-linear. Despite this, the controls on tidewater processes are poorly understood and a process based description of them is lacking from the present generation of coupled ice sheet models. We present details from an innovative study where two survey techniques are integrated to enable the construction of accurate, ~m resolution 3d digital terrain models (DTMs) of the aerial and submarine ice front of calving outlet glaciers. A 2km range terrestrial laser scanner was combined with a 416KHz swath-interferometric system and corrected via an inertial motion unit stabilized by RTK GPS and gyro-compass data. The system was mounted aboard a heavy displacement (20,000kg) yacht in addition to a light displacement (100kg) semi-autonomous boat and used to image the aerial and submarine calving fronts of two large outlet glaciers in W Greenland. Six daily surveys, each 2.5km long were repeated across Lille Glacier during which significant ice flow, melt and calving events were observed and captured from on-ice GPS stations and time-lapse sequences. A curtain of CTD and velocity casts were also conducted to constrain the fresh and oceanic mass and energy fluxes within the fjord. The residual of successive DTMs yield the spatial pattern of frontal change enabling the processes of aerial and submarine calving and melt to be quantified and constrained in unprecedented detail. These observed frontal changes are tentatively related to local dynamic, atmospheric and oceanographic processes that drive them. A partial survey of Store Glacier (~7km calving front & W Greenland 2nd largest outlet after Jakobshavn Isbrae) was conducted, indicating that the technique is successful up to ~500m from the ice front and to a similar water depth. These data sets show that it is possible to integrate and build 3d DTMs at the metre-scale both above and below the water surface. The successful acquisition from our semi-autonomous vessel supervised up to 2km away greatly eases repeat surveys and reduces the exposure of equipment and personnel to the risks posed by large, active calving glaciers. Lille Glacier and s/v Gambo surveyed & photographed from the semi-autonomous vessel. Mock-up of Lille Glacier calving front and fore-bay submarine topography imaged by interferometric swath-bathymetry.

46 CFR 59.10-10 - Corroded surfaces.

Code of Federal Regulations, 2010 CFR

2010-10-01

... VESSELS AND APPURTENANCES Welding Repairs to Boilers and Pressure Vessels in -Service § 59.10-10 Corroded surfaces. (a) Corroded surfaces in the calking edges of circumferential seams may be built up by welding to... inches in length in a circumferential direction. (2) In all repairs to circumferential seams by welding...

46 CFR 59.10-10 - Corroded surfaces.

Code of Federal Regulations, 2011 CFR

2011-10-01

... VESSELS AND APPURTENANCES Welding Repairs to Boilers and Pressure Vessels in -Service § 59.10-10 Corroded surfaces. (a) Corroded surfaces in the calking edges of circumferential seams may be built up by welding to... inches in length in a circumferential direction. (2) In all repairs to circumferential seams by welding...

46 CFR 59.10-10 - Corroded surfaces.

Code of Federal Regulations, 2013 CFR

2013-10-01

... VESSELS AND APPURTENANCES Welding Repairs to Boilers and Pressure Vessels in -Service § 59.10-10 Corroded surfaces. (a) Corroded surfaces in the calking edges of circumferential seams may be built up by welding to... inches in length in a circumferential direction. (2) In all repairs to circumferential seams by welding...

46 CFR 59.10-10 - Corroded surfaces.

Code of Federal Regulations, 2012 CFR

2012-10-01

... VESSELS AND APPURTENANCES Welding Repairs to Boilers and Pressure Vessels in -Service § 59.10-10 Corroded surfaces. (a) Corroded surfaces in the calking edges of circumferential seams may be built up by welding to... inches in length in a circumferential direction. (2) In all repairs to circumferential seams by welding...

46 CFR 59.10-10 - Corroded surfaces.

Code of Federal Regulations, 2014 CFR

2014-10-01

... VESSELS AND APPURTENANCES Welding Repairs to Boilers and Pressure Vessels in -Service § 59.10-10 Corroded surfaces. (a) Corroded surfaces in the calking edges of circumferential seams may be built up by welding to... inches in length in a circumferential direction. (2) In all repairs to circumferential seams by welding...

46 CFR 172.030 - Exemptions for certain vessels.

Code of Federal Regulations, 2010 CFR

2010-10-01

... to a minimum by carrying as few slack holds as possible. (4) Each slack surface must be leveled. (5...=(0.268 r) if r is slack surface of grain, i.e...=breadth of slack grain surface (m L=Length of compartment (m) Disp.=Displacement of vessel (tons) SF...

Vacuum-isolation vessel and method for measurement of thermal noise in microphones

NASA Technical Reports Server (NTRS)

Zuckerwar, Allan J. (Inventor); Ngo, Kim Chi T. (Inventor)

1992-01-01

The vacuum isolation vessel and method in accordance with the present invention are used to accurately measure thermal noise in microphones. The apparatus and method could be used in a microphone calibration facility or any facility used for testing microphones. Thermal noise is measured to determine the minimum detectable sound pressure by the microphone. Conventional isolation apparatus and methods have been unable to provide an acoustically quiet and substantially vibration free environment for accurately measuring thermal noise. In the present invention, an isolation vessel assembly comprises a vacuum sealed outer vessel, a vacuum sealed inner vessel, and an interior suspension assembly coupled between the outer and inner vessels for suspending the inner vessel within the outer vessel. A noise measurement system records thermal noise data from the isolation vessel assembly. A vacuum system creates a vacuum between an internal surface of the outer vessel and an external surface of the inner vessel. The present invention thus provides an acoustically quiet environment due to the vacuum created between the inner and outer vessels and a substantially vibration free environment due to the suspension assembly suspending the inner vessel within the outer vessel. The thermal noise in the microphone, effectively isolated according to the invention, can be accurately measured.

Fuzzy logic path planning system for collision avoidance by an autonomous rover vehicle

NASA Technical Reports Server (NTRS)

Murphy, Michael G.

1993-01-01

The Space Exploration Initiative of the United States will make great demands upon NASA and its limited resources. One aspect of great importance will be providing for autonomous (unmanned) operation of vehicles and/or subsystems in space flight and surface exploration. An additional, complicating factor is that much of the need for autonomy of operation will take place under conditions of great uncertainty or ambiguity. Issues in developing an autonomous collision avoidance subsystem within a path planning system for application in a remote, hostile environment that does not lend itself well to remote manipulation by Earth-based telecommunications is addressed. A good focus is unmanned surface exploration of Mars. The uncertainties involved indicate that robust approaches such as fuzzy logic control are particularly appropriate. Four major issues addressed are (1) avoidance of a fuzzy moving obstacle; (2) backoff from a deadend in a static obstacle environment; (3) fusion of sensor data to detect obstacles; and (4) options for adaptive learning in a path planning system. Examples of the need for collision avoidance by an autonomous rover vehicle on the surface of Mars with a moving obstacle would be wind-blown debris, surface flow or anomalies due to subsurface disturbances, another vehicle, etc. The other issues of backoff, sensor fusion, and adaptive learning are important in the overall path planning system.

Radial flow pulse jet mixer

DOEpatents

VanOsdol, John G.

2013-06-25

The disclosure provides a pulse jet mixing vessel for mixing a plurality of solid particles. The pulse jet mixing vessel is comprised of a sludge basin, a flow surface surrounding the sludge basin, and a downcoming flow annulus between the flow surface and an inner shroud. The pulse jet mixing vessel is additionally comprised of an upper vessel pressurization volume in fluid communication with the downcoming flow annulus, and an inner shroud surge volume separated from the downcoming flow annulus by the inner shroud. When the solid particles are resting on the sludge basin and a fluid such as water is atop the particles and extending into the downcoming flow annulus and the inner shroud surge volume, mixing occurs by pressurization of the upper vessel pressurization volume, generating an inward radial flow over the flow surface and an upwash jet at the center of the sludge basin.

Intelligent Autonomy for Unmanned Surface and Underwater Vehicles

NASA Technical Reports Server (NTRS)

Huntsberger, Terry; Woodward, Gail

2011-01-01

As the Autonomous Underwater Vehicle (AUV) and Autonomous Surface Vehicle (ASV) platforms mature in endurance and reliability, a natural evolution will occur towards longer, more remote autonomous missions. This evolution will require the development of key capabilities that allow these robotic systems to perform a high level of on-board decisionmaking, which would otherwise be performed by humanoperators. With more decision making capabilities, less a priori knowledge of the area of operations would be required, as these systems would be able to sense and adapt to changing environmental conditions, such as unknown topography, currents, obstructions, bays, harbors, islands, and river channels. Existing vehicle sensors would be dual-use; that is they would be utilized for the primary mission, which may be mapping or hydrographic reconnaissance; as well as for autonomous hazard avoidance, route planning, and bathymetric-based navigation. This paper describes a tightly integrated instantiation of an autonomous agent called CARACaS (Control Architecture for Robotic Agent Command and Sensing) developed at JPL (Jet Propulsion Laboratory) that was designed to address many of the issues for survivable ASV/AUV control and to provide adaptive mission capabilities. The results of some on-water tests with US Navy technology test platforms are also presented.

Pressure sensor for sealed containers

DOEpatents

Hodges, Franklin R.

2001-01-01

A magnetic pressure sensor for sensing a pressure change inside a sealed container. The sensor includes a sealed deformable vessel having a first end attachable to an interior surface of the sealed container, and a second end. A magnet mounted to the vessel second end defining a distance away from the container surface provides an externally detectable magnetic field. A pressure change inside the sealed container causes deformation of the vessel changing the distance of the magnet away from the container surface, and thus the detectable intensity of the magnetic field.

Target Trailing With Safe Navigation for Maritime Autonomous Surface Vehicles

NASA Technical Reports Server (NTRS)

Wolf, Michael; Kuwata, Yoshiaki; Zarzhitsky, Dimitri V.

2013-01-01

This software implements a motion-planning module for a maritime autonomous surface vehicle (ASV). The module trails a given target while also avoiding static and dynamic surface hazards. When surface hazards are other moving boats, the motion planner must apply International Regulations for Avoiding Collisions at Sea (COLREGS). A key subset of these rules has been implemented in the software. In case contact with the target is lost, the software can receive and follow a "reacquisition route," provided by a complementary system, until the target is reacquired. The programmatic intention is that the trailed target is a submarine, although any mobile naval platform could serve as the target. The algorithmic approach to combining motion with a (possibly moving) goal location, while avoiding local hazards, may be applicable to robotic rovers, automated landing systems, and autonomous airships. The software operates in JPL s CARACaS (Control Architecture for Robotic Agent Command and Sensing) software architecture and relies on other modules for environmental perception data and information on the predicted detectability of the target, as well as the low-level interface to the boat controls.

Autonomous multifunctional nanobrushes-autonomous materials

NASA Astrophysics Data System (ADS)

Ghasemi-Nejhad, Mehrdad N.; Tius, Marcus A.

2007-04-01

In this work, taking advantage of carbon nanotubes' small size, and exceptional mechanical, chemical and electrical properties, we report on a series of nano-synthesis procedures that combine conventional chemical vapor deposition and selective substrate area growth followed by chemical functionalizations to fabricate functionalized nano-brushes from aligned carbon nanotube arrays and chemically selective functional groups. The high aspect ratio and small dimension, mechanical stability and flexibility, surface chemical and adhesive characteristics of carbon nanotubes provide opportunities to create nano-brushes with selected chemical functionalities. The nano-brushes are made from aligned multi-walled carbon nanotube bristles grafted onto long SiC fiber handles in various configurations and functionalized with various chemical functional groups. These nano-brushes can easily be manipulated physically, either manually or with the aid of motors. Here, we explain the autonomous characteristics of the functionalized nano-brushes employing functional chemical groups such that the nano-brush can potentially collect various metal particles, ions, and contaminants from liquid solutions and the air environment, autonomously. These functionalized multiwalled carbon nanotube based nano-brushes can work swiftly in both liquid and air environments. With surface modification and functionalization, the nanotube nano-brushes can potentially become a versatile nano-devices in many chemical and biological applications, where they can autonomously pick up the particles they encounter since they can be chemically programmed to function as Autonomous Chemical Nano Robots (ACNR).

SAMOS Surface Fluxes

NASA Astrophysics Data System (ADS)

Smith, Shawn; Bourassa, Mark

2014-05-01

The development of a new surface flux dataset based on underway meteorological observations from research vessels will be presented. The research vessel data center at the Florida State University routinely acquires, quality controls, and distributes underway surface meteorological and oceanographic observations from over 30 oceanographic vessels. These activities are coordinated by the Shipboard Automated Meteorological and Oceanographic System (SAMOS) initiative in partnership with the Rolling Deck to Repository (R2R) project. Recently, the SAMOS data center has used these underway observations to produce bulk flux estimates for each vessel along individual cruise tracks. A description of this new flux product, along with the underlying data quality control procedures applied to SAMOS observations, will be provided. Research vessels provide underway observations at high-temporal frequency (1 min. sampling interval) that include navigational (position, course, heading, and speed), meteorological (air temperature, humidity, wind, surface pressure, radiation, rainfall), and oceanographic (surface sea temperature and salinity) samples. Vessels recruited to the SAMOS initiative collect a high concentration of data within the U.S. continental shelf and also frequently operate well outside routine shipping lanes, capturing observations in extreme ocean environments (Southern, Arctic, South Atlantic, and South Pacific oceans). These observations are atypical for their spatial and temporal sampling, making them very useful for many applications including validation of numerical models and satellite retrievals, as well as local assessments of natural variability. Individual SAMOS observations undergo routine automated quality control and select vessels receive detailed visual data quality inspection. The result is a quality-flagged data set that is ideal for calculating turbulent flux estimates. We will describe the bulk flux algorithms that have been applied to the observations and the choices of constants that are used. Analysis of the preliminary SAMOS flux products will be presented, including spatial and temporal coverage for each derived parameter. The unique quality and sampling locations of research vessel observations and their independence from many models and products makes them ideal for validation studies. The strengths and limitations of research observations for flux validation studies will be discussed. The authors welcome a discussion with the flux community regarding expansion of the SAMOS program to include additional international vessels, thus facilitating and expansion of this research vessel-based flux product.

Characterizing the relative contributions of large vessels to total ocean noise fields: a case study using the Gerry E. Studds Stellwagen Bank National Marine Sanctuary.

PubMed

Hatch, Leila; Clark, Christopher; Merrick, Richard; Van Parijs, Sofie; Ponirakis, Dimitri; Schwehr, Kurt; Thompson, Michael; Wiley, David

2008-11-01

In 2006, we used the U.S. Coast Guard's Automatic Identification System (AIS) to describe patterns of large commercial ship traffic within a U.S. National Marine Sanctuary located off the coast of Massachusetts. We found that 541 large commercial vessels transited the greater sanctuary 3413 times during the year. Cargo ships, tankers, and tug/tows constituted 78% of the vessels and 82% of the total transits. Cargo ships, tankers, and cruise ships predominantly used the designated Boston Traffic Separation Scheme, while tug/tow traffic was concentrated in the western and northern portions of the sanctuary. We combined AIS data with low-frequency acoustic data from an array of nine autonomous recording units analyzed for 2 months in 2006. Analysis of received sound levels (10-1000 Hz, root-mean-square pressure re 1 microPa +/- SE) averaged 119.5 +/- 0.3 dB at high-traffic locations. High-traffic locations experienced double the acoustic power of less trafficked locations for the majority of the time period analyzed. Average source level estimates (71-141 Hz, root-mean-square pressure re 1 microPa +/- SE) for individual vessels ranged from 158 +/- 2 dB (research vessel) to 186 +/- 2 dB (oil tanker). Tankers were estimated to contribute 2 times more acoustic power to the region than cargo ships, and more than 100 times more than research vessels. Our results indicate that noise produced by large commercial vessels was at levels and within frequencies that warrant concern among managers regarding the ability of endangered whales to maintain acoustic contact within greater sanctuary waters.

Unmanned surface vessel (USV) systems for bridge inspection : [summary].

DOT National Transportation Integrated Search

2016-08-01

Florida Atlantic University researchers studied the : use of unmanned surface vessels (USVs) for bridge : inspection. The general concept is that a bridge : inspection team would use an USV to perform an : initial survey of structures underwater and ...

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

NASA Astrophysics Data System (ADS)

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

2017-05-01

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

Characterizing the effects of cladding on semi-elliptical longitudinal surface flaws in cylindrical vessels subjected to internal pressure

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

Killian, D.E.; Yoon, K.K.

1996-12-01

Flaws on the inside surface of cladded reactor vessels are often analyzed by modelling the carbon steel base metal without consideration of a layer of stainless steel cladding material, thus ignoring the effects of this bimetallic discontinuity. Adding cladding material to the inside surface of a finite element model of a vessel raises concerns regarding adequate mesh refinement in the vicinity of the base metal/cladding interface. This paper presents results of three-dimensional linear stress analysis that has been performed to obtain stress intensity factors for clad and unclad reactor vessels subjected to internal pressure loading. The study concentrates on semi-ellipticalmore » longitudinal surface flaws with a 6 to 1 length-to-depth ratio and flaw depths of 1/8 and 1/4 of the base metal thickness. Various meshing schemes are evaluated for modelling the crack front profile, with particular emphasis on the region near the inside surface and at the base metal/cladding interface. The shape of the crack front profile through the cladding layer and the number of finite elements used to discretize the cladding thickness are found to have a significant influence on typical fracture mechanic measures of the crack tip stress fields. Results suggest that the stress intensity factor at the inner surface of a cladded vessel may be affected as much by the finite element mesh near the surface as by the material discontinuity between the two parts of the structure.« less

Expert system isssues in automated, autonomous space vehicle rendezvous

NASA Technical Reports Server (NTRS)

Goodwin, Mary Ann; Bochsler, Daniel C.

1987-01-01

The problems involved in automated autonomous rendezvous are briefly reviewed, and the Rendezvous Expert (RENEX) expert system is discussed with reference to its goals, approach used, and knowledge structure and contents. RENEX has been developed to support streamlining operations for the Space Shuttle and Space Station program and to aid definition of mission requirements for the autonomous portions of rendezvous for the Mars Surface Sample Return and Comet Nucleus Sample return unmanned missions. The experience with REMEX to date and recommendations for further development are presented.

An autonomous flying vehicle for Mars exploration

NASA Astrophysics Data System (ADS)

Bouras, Peter; Fox, Tim

1990-09-01

A remotely reprogrammable, autonomous flying craft for surveying and mapping the Martian surface environment is presented. This solar powered, modified flying wing design could cover about 2000 statute miles while maneuvering at Mach 0.3. The craft is configured to fly one km above the surface, measuring atmospheric properties, performing subsurface mapping, mapping the surface topography, and searching for the presence of water and perhaps life. A 35 kg scientific payload, plus communication and control electronics, are placed spanwise inside the flying wing, removing the requirement for a normal fuselage, and reducing structural needs. Thrust is provided by a two-bladed electrically driven propeller motorized by high-efficiency solar cells.

Extension of Murray's law using a non-Newtonian model of blood flow.

PubMed

Revellin, Rémi; Rousset, François; Baud, David; Bonjour, Jocelyn

2009-05-15

So far, none of the existing methods on Murray's law deal with the non-Newtonian behavior of blood flow although the non-Newtonian approach for blood flow modelling looks more accurate. MODELING: In the present paper, Murray's law which is applicable to an arterial bifurcation, is generalized to a non-Newtonian blood flow model (power-law model). When the vessel size reaches the capillary limitation, blood can be modeled using a non-Newtonian constitutive equation. It is assumed two different constraints in addition to the pumping power: the volume constraint or the surface constraint (related to the internal surface of the vessel). For a seek of generality, the relationships are given for an arbitrary number of daughter vessels. It is shown that for a cost function including the volume constraint, classical Murray's law remains valid (i.e. SigmaR(c) = cste with c = 3 is verified and is independent of n, the dimensionless index in the viscosity equation; R being the radius of the vessel). On the contrary, for a cost function including the surface constraint, different values of c may be calculated depending on the value of n. We find that c varies for blood from 2.42 to 3 depending on the constraint and the fluid properties. For the Newtonian model, the surface constraint leads to c = 2.5. The cost function (based on the surface constraint) can be related to entropy generation, by dividing it by the temperature. It is demonstrated that the entropy generated in all the daughter vessels is greater than the entropy generated in the parent vessel. Furthermore, it is shown that the difference of entropy generation between the parent and daughter vessels is smaller for a non-Newtonian fluid than for a Newtonian fluid.

Fiber glass prevents cracking of polyurethane foam insulation on cryogenic vessels

NASA Technical Reports Server (NTRS)

Forge, D. A.

1968-01-01

Fiber glass material, placed between polyurethane foam insulation and the outer surfaces of cryogenic vessels, retains its resilience at cryogenic temperatures and provides an expansion layer between the metal surfaces and the polyurethane foam, preventing cracking of the latter.

The water-filled versus air-filled status of vessels cut open in air: the 'Scholander assumption' revisited

Treesearch

M.T. Tyree; H. Cochard; P. Cruziat

2003-01-01

When petioles of transpiring leaves are cut in the air, according to the 'Scholander assumption', the vessels cut open should fill with air as the water is drained away by continued transpiration, The distribution of air-filled vessels versus distance from the cut surface should match the distribution of lengths of 'open vessels', i.e. vessels cut...

High resolution non-contact interior profilometer

DOEpatents

Piltch, Martin S.; Patterson, R. Alan; Leeches, Gerald W.; Nierop, John Van; Teti, John J.

2001-01-01

Apparatus and method for inspecting the interior surfaces of devices such as vessels having a single entry port. Laser energy is launched into the vessel, and the light reflected from the interior surfaces is interfered with reference laser energy to produce an interference pattern. This interference pattern is analyzed to reveal information about the condition of the interior surfaces of the device inspected.

Assessing Plankton and Particles with an Autonomous Imaging LOPC

DTIC Science & Technology

2007-09-30

been modified to operate autonomously by auto-starting its programs on power-up and storing its data to an onboard flashcard . Since data transfer to... flashcard is a slow process, storage will occur when the AUV surfaces for a position fix. Data acquisition will commence as the AUV descends >5m

Testing of self-repairing composite airplane components by use of CAI and the release of the repair chemicals from carefully inserted small tubes

NASA Astrophysics Data System (ADS)

Dry, Carolyn

2007-04-01

The research on self repair of airplane components, under an SBIR phase II with Wright Patterson Air Force Base, has investigated the attributes and best end use applications for such a technology. These attributes include issues related to manufacturability, cost, potential benefits such as weight reduction, and cost reduction. The goal of our research has been to develop self-repairing composites with unique strength for air vehicles. Our revolutionary approach involves the autonomous release of repair chemicals from within the composite matrix itself. The repair agents are contained in hollow, structural fibers that are embedded within the matrix. Under stress, the composite senses external environmental factors and reacts by releasing the repair agents from within the hollow vessels. This autonomous response occurs wherever and whenever cracking, debonding or other matrix damage transpires. Superior performance over the life of the composite is achieved through this self-repairing mechanism. The advantages to the military would be safely executed missions, fewer repairs and eventually lighter vehicles. In particular the research has addressed the issues by correlating the impact of the various factors, such as 1) delivery vessel placement, shape/size and effect on composite strength, chemicals released and their effect on the matrix, release trigger and efficacy and any impact on matrix properties 2) impact of composite processing methods that involve heat and pressure on the repair vessels. Our self repairing system can be processed at temperatures of 300-350F, repairs in less than 30 seconds and does not damage the composite by repair fiber insertion or chemical release. Scaling up and manufacture of components has revealed that anticipating potential problems allowed us to avoid those associated with processing temperatures and pressures. The presentation will focus on compression after impact testing and the placement of repair fibers/tubes into prepreg laminates.

Morphological differences in coronary arteries following rotational atherectomy versus balloon angioplasty: ultrasound and angioscopic observations

NASA Astrophysics Data System (ADS)

Bass, Theodore A.; Gilmore, Paul S.; White, Christopher J.; Chami, Youssef G.; Kircher, Barbara J.; Conetta, Donald A.

1993-09-01

Percutaneous transluminal coronary rotational atherectomy (PTCRA) is an exciting new device to recannulate obstructed coronary arteries. This device works as a high speed `drill,' selectively cutting hard atherosclerotic plaque while preferentially sparing the softer, less diseased vascular luminal surface. At speeds as high as 200,000 rpm the plaque is pulverized into small particles easily handled by the circulatory system with no untoward clinical sequela. Balloon angioplasty does not remove atherosclerotic plaque. It dilates the vessel by mechanically stretching, compressing and splitting the plaque and vessel lining. We compare morphological and surface luminal characteristics of vessels post PTCRA to vessels post PTCA.

A scaling law for the local CHF on the external bottom side of a fully submerged reactor vessel

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

Cheung, F.B.; Haddad, K.H.; Liu, Y.C.

1997-02-01

A scaling law for estimating the local critical heat flux on the outer surface of a heated hemispherical vessel that is fully submerged in water has been developed from the results of an advanced hydrodynamic CHF model for pool boiling on a downward facing curved heating surface. The scaling law accounts for the effects of the size of the vessel, the level of liquid subcooling, the intrinsic properties of the fluid, and the spatial variation of the local critical heat flux along the heating surface. It is found that for vessels with diameters considerably larger than the characteristic size ofmore » the vapor masses, the size effect on the local critical heat flux is limited almost entirely to the effect of subcooling associated with the local liquid head. When the subcooling effect is accounted for separately, the local CHF limit is nearly independent of the vessel size. Based upon the scaling law developed in this work, it is possible to merge, within the experimental uncertainties, all the available local CHF data obtained for various vessel sizes under both saturated and subcooled boiling conditions into a single curve. Applications of the scaling law to commercial-size vessels have been made for various system pressures and water levels above the heated vessel. Over the range of conditions explored in this study, the local CHF limit is found to increase by a factor of two or more from the bottom center to the upper edge of the vessel. Meanwhile, the critical heat flux at a given angular position of the heated vessel is also found to increase appreciably with the system pressure and the water level.« less

Observations on the behavior of bowhead whales (Balaena mysticetus) in the presence of operating seismic exploration vessels in the Alaskan Beaufort Sea

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

Ljungblad, D.K.; Wuersig, B.; Swartz, S.L.

1985-10-01

The response of bowhead whales to active geophysical vessels was observed during the course of 4 field experiments conducted in the Alaskan Beaufort Sea, September 1984. Conspicuous short-term behavioral changes were observed when active vessels approached to within 10km of bowheads, with the strongest responses occurring when whales were within 5km of active vessels. Behavioral responses included shorter surfacing and dive times, fewer blows per surfacing, and longer blow intervals. Total avoidance responses occured at vessel distances of 1.25km, 7.2km, 3.5km and 3.5km with associated measured sound levels from the seismic airgun arrays of 152dB, 164dB, 178dB and 163dB, respectively.

Advances in Autonomous Systems for Missions of Space Exploration

NASA Astrophysics Data System (ADS)

Gross, A. R.; Smith, B. D.; Briggs, G. A.; Hieronymus, J.; Clancy, D. J.

New missions of space exploration will require unprecedented levels of autonomy to successfully accomplish their objectives. Both inherent complexity and communication distances will preclude levels of human involvement common to current and previous space flight missions. With exponentially increasing capabilities of computer hardware and software, including networks and communication systems, a new balance of work is being developed between humans and machines. This new balance holds the promise of meeting the greatly increased space exploration requirements, along with dramatically reduced design, development, test, and operating costs. New information technologies, which take advantage of knowledge-based software, model-based reasoning, and high performance computer systems, will enable the development of a new generation of design and development tools, schedulers, and vehicle and system health monitoring and maintenance capabilities. Such tools will provide a degree of machine intelligence and associated autonomy that has previously been unavailable. These capabilities are critical to the future of space exploration, since the science and operational requirements specified by such missions, as well as the budgetary constraints that limit the ability to monitor and control these missions by a standing army of ground- based controllers. System autonomy capabilities have made great strides in recent years, for both ground and space flight applications. Autonomous systems have flown on advanced spacecraft, providing new levels of spacecraft capability and mission safety. Such systems operate by utilizing model-based reasoning that provides the capability to work from high-level mission goals, while deriving the detailed system commands internally, rather than having to have such commands transmitted from Earth. This enables missions of such complexity and communications distance as are not otherwise possible, as well as many more efficient and low cost applications. One notable example of such missions are those to explore for the existence of water on planets such as Mars and the moons of Jupiter. It is clear that water does not exist on the surfaces of such bodies, but may well be located at some considerable depth below the surface, thus requiring a subsurface drilling capability. Subsurface drilling on planetary surfaces will require a robust autonomous control and analysis system, currently a major challenge, but within conceivable reach of planned technology developments. This paper will focus on new and innovative software for remote, autonomous, space systems flight operations, including flight test results, lessons learned, and implications for the future. An additional focus will be on technologies for planetary exploration using autonomous systems and astronaut-assistance systems that employ new spoken language technology. Topics to be presented will include a description of key autonomous control concepts, illustrated by the Remote Agent program that commanded the Deep Space 1 spacecraft to new levels of system autonomy, recent advances in distributed autonomous system capabilities, and concepts for autonomous vehicle health management systems. A brief description of teaming spacecraft and rovers for complex exploration missions will also be provided. New software for autonomous science data acquisition for planetary exploration will also be described, as well as advanced systems for safe planetary landings. Current results of autonomous planetary drilling system research will be presented. A key thrust within NASA is to develop technologies that will leverage the capabilities of human astronauts during planetary surface explorations. One such technology is spoken dialogue interfaces, which would allow collaboration with semi-autonomous agents that are engaged in activities that are normally accomplished using language, e.g., astronauts in space suits interacting with groups of semi-autonomous rovers and other astronauts. This technology will be described and discussed in the context of future exploration missions and the major new capabilities enabled by such systems. Finally, plans and directions for the future of autonomous systems will be presented.

The digital code driven autonomous synthesis of ibuprofen automated in a 3D-printer-based robot.

PubMed

Kitson, Philip J; Glatzel, Stefan; Cronin, Leroy

2016-01-01

An automated synthesis robot was constructed by modifying an open source 3D printing platform. The resulting automated system was used to 3D print reaction vessels (reactionware) of differing internal volumes using polypropylene feedstock via a fused deposition modeling 3D printing approach and subsequently make use of these fabricated vessels to synthesize the nonsteroidal anti-inflammatory drug ibuprofen via a consecutive one-pot three-step approach. The synthesis of ibuprofen could be achieved on different scales simply by adjusting the parameters in the robot control software. The software for controlling the synthesis robot was written in the python programming language and hard-coded for the synthesis of ibuprofen by the method described, opening possibilities for the sharing of validated synthetic 'programs' which can run on similar low cost, user-constructed robotic platforms towards an 'open-source' regime in the area of chemical synthesis.

The digital code driven autonomous synthesis of ibuprofen automated in a 3D-printer-based robot

PubMed Central

Kitson, Philip J; Glatzel, Stefan

2016-01-01

An automated synthesis robot was constructed by modifying an open source 3D printing platform. The resulting automated system was used to 3D print reaction vessels (reactionware) of differing internal volumes using polypropylene feedstock via a fused deposition modeling 3D printing approach and subsequently make use of these fabricated vessels to synthesize the nonsteroidal anti-inflammatory drug ibuprofen via a consecutive one-pot three-step approach. The synthesis of ibuprofen could be achieved on different scales simply by adjusting the parameters in the robot control software. The software for controlling the synthesis robot was written in the python programming language and hard-coded for the synthesis of ibuprofen by the method described, opening possibilities for the sharing of validated synthetic ‘programs’ which can run on similar low cost, user-constructed robotic platforms towards an ‘open-source’ regime in the area of chemical synthesis. PMID:28144350

Harvesting contaminants from liquid

DOEpatents

Simpson, John T.; Hunter, Scott R.

2016-05-31

Disclosed are examples of apparatuses for evaporative purification of a contaminated liquid. In each example, there is a vessel for storing the contaminated fluid. The vessel includes a surface coated with a layer of superhydrophobic material and the surface is at least partially in contact with the contaminated liquid. The contaminants do not adhere to the surface as the purified liquid evaporates, thus allowing the contaminants to be harvested.

Nuclear reactor support and seismic restraint with in-vessel core retention cooling features

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

Edwards, Tyler A.; Edwards, Michael J.

A nuclear reactor including a lateral seismic restraint with a vertically oriented pin attached to the lower vessel head and a mating pin socket attached to the floor. Thermally insulating materials are disposed alongside the exterior surface of a lower portion of the reactor pressure vessel including at least the lower vessel head.

40 CFR 60.112b - Standard for volatile organic compounds (VOC).

Code of Federal Regulations, 2010 CFR

2010-07-01

... for Volatile Organic Liquid Storage Vessels (Including Petroleum Liquid Storage Vessels) for Which... specifications: (i) The internal floating roof shall rest or float on the liquid surface (but not necessarily in... be floating on the liquid surface at all times, except during initial fill and during those intervals...

40 CFR 60.112b - Standard for volatile organic compounds (VOC).

Code of Federal Regulations, 2012 CFR

2012-07-01

... for Volatile Organic Liquid Storage Vessels (Including Petroleum Liquid Storage Vessels) for Which... specifications: (i) The internal floating roof shall rest or float on the liquid surface (but not necessarily in... be floating on the liquid surface at all times, except during initial fill and during those intervals...

40 CFR 60.112b - Standard for volatile organic compounds (VOC).

Code of Federal Regulations, 2014 CFR

2014-07-01

... for Volatile Organic Liquid Storage Vessels (Including Petroleum Liquid Storage Vessels) for Which... specifications: (i) The internal floating roof shall rest or float on the liquid surface (but not necessarily in... be floating on the liquid surface at all times, except during initial fill and during those intervals...

40 CFR 60.112b - Standard for volatile organic compounds (VOC).

Code of Federal Regulations, 2013 CFR

2013-07-01

... for Volatile Organic Liquid Storage Vessels (Including Petroleum Liquid Storage Vessels) for Which... specifications: (i) The internal floating roof shall rest or float on the liquid surface (but not necessarily in... be floating on the liquid surface at all times, except during initial fill and during those intervals...

40 CFR 60.112b - Standard for volatile organic compounds (VOC).

Code of Federal Regulations, 2011 CFR

2011-07-01

... for Volatile Organic Liquid Storage Vessels (Including Petroleum Liquid Storage Vessels) for Which... specifications: (i) The internal floating roof shall rest or float on the liquid surface (but not necessarily in... be floating on the liquid surface at all times, except during initial fill and during those intervals...

Path Planning Algorithms for the Adaptive Sensor Fleet

NASA Technical Reports Server (NTRS)

Stoneking, Eric; Hosler, Jeff

2005-01-01

The Adaptive Sensor Fleet (ASF) is a general purpose fleet management and planning system being developed by NASA in coordination with NOAA. The current mission of ASF is to provide the capability for autonomous cooperative survey and sampling of dynamic oceanographic phenomena such as current systems and algae blooms. Each ASF vessel is a software model that represents a real world platform that carries a variety of sensors. The OASIS platform will provide the first physical vessel, outfitted with the systems and payloads necessary to execute the oceanographic observations described in this paper. The ASF architecture is being designed for extensibility to accommodate heterogenous fleet elements, and is not limited to using the OASIS platform to acquire data. This paper describes the path planning algorithms developed for the acquisition phase of a typical ASF task. Given a polygonal target region to be surveyed, the region is subdivided according to the number of vessels in the fleet. The subdivision algorithm seeks a solution in which all subregions have equal area and minimum mean radius. Once the subregions are defined, a dynamic programming method is used to find a minimum-time path for each vessel from its initial position to its assigned region. This path plan includes the effects of water currents as well as avoidance of known obstacles. A fleet-level planning algorithm then shuffles the individual vessel assignments to find the overall solution which puts all vessels in their assigned regions in the minimum time. This shuffle algorithm may be described as a process of elimination on the sorted list of permutations of a cost matrix. All these path planning algorithms are facilitated by discretizing the region of interest onto a hexagonal tiling.

Validation of HF Radar ocean surface currents in the Ibiza Channel using lagrangian drifters, moored current meter and underwater gliders

NASA Astrophysics Data System (ADS)

Lana, Arancha; Fernández, Vicente; Orfila, Alejandro; Troupin, Charles; Tintoré, Joaquín

2015-04-01

SOCIB High Frequency (HF) radar is one component of a multi-platform system located in the Balearic Islands and made up of Lagrangian platforms (profilers and drifting buoys), fixed stations (sea-level, weather, mooring and coastal), beach monitoring (camera), gliders, a research vessel as well as an ocean forecast system (waves and hydrodynamics). The HF radar system overlooks the Ibiza Channel, known as a 'choke point" where Atlantic and Mediterranean water masses interact and where meridional exchanges of water mass properties between the Balearic and the Algerian sub-basins take place. In order to determine the reliability of surface velocity measurements in this area, a quality assessment of the HF Radar is essential. We present the results of several validation experiments performed in the Ibiza Channel in 2013 and 2014. Of particular interest is an experiment started in September 2014 when a set of 13 surface drifters with different shapes and drogue lengths were released in the area covered by the HF radar. The drifter trajectories can be examined following the SOCIB Deployment Application (DAPP): http://apps.socib.es/dapp. Additionally, a 1-year long time series of surface currents obtained from a moored surface current-meter located in the Ibiza Channel, inside the area covered by the HF radar, was also used as a useful complementary validation exercise. Direct comparison between both radial surface currents from each radar station and total derived velocities against drifters and moored current meter velocities provides an assessment of the HF radar data quality at different temporal periods and geographical areas. Statistics from these comparisons give good correlation and low root-mean-square deviation. The results will be discussed for different months, geographical areas and types of surface drifters and wind exposure. Moreover, autonomous underwater glider constitutes an additional source of information for the validation of the observed velocity structures and some statistics will be presented.

Luminal surface fabrication for cardiovascular prostheses

NASA Technical Reports Server (NTRS)

Deininger, William D. (Inventor); Gabriel, Stephen B. (Inventor)

1988-01-01

A method is provided for forming a mold surface with microscopic upstanding pillars for molding the inside surface of a vascular prostheses (synthetic blood vessel). The mold article is formed from a quantity of Teflon (polytetrafluoroethylene) which has a polished, flat surface on which a gold film has been sputter deposited. A photoresist layer, which cannot adhere directly to Teflon, adheres to the gold. The photoresist is exposed and developed leaving a sputter resistant mask defining the desired pillar locations, and the resulting workpiece is ion etched to form the pillars in the Teflon. A synthetic blood vessel material is cast against the Teflon mold to form blind recesses on the inside of the synthetic blood vessel, with the recesses being of predetermined uniform cross section and present in a predetermined uniform pattern.

Enhanced autonomic shutdown of Li-ion batteries by polydopamine coated polyethylene microspheres

DOE PAGES

Baginska, Marta; Blaiszik, Benjamin J.; Rajh, Tijana; ...

2014-07-17

Thermally triggered autonomic shutdown of a Lithium-ion (Li-ion) battery is demonstrated using polydopamine (PDA)-coated polyethylene microspheres applied onto a battery anode. The microspheres are dispersed in a buffered 10 mM dopamine salt solution and the pH is raised to initiate the polymerization and coat the microspheres. Coated microspheres are then mixed with an aqueous binder, applied onto a battery anode surface, dried, and incorporated into Li-ion coin cells. FTIR and Raman spectroscopy are used to verify the presence of the polydopamine on the surface of the microspheres. Scanning electron microscopy is used to examine microsphere surface morphology and resulting anodemore » coating quality. Charge and discharge capacity, as well as impedance, are measured for Li-ion coin cells as a function of microsphere content. Autonomous shutdown is achieved by applying 1.7 mg cm –2 of PDA-coated microspheres to the electrode. Furthermore, the PDA coating significantly reduces the mass of microspheres for effective shutdown compared to our prior work with uncoated microspheres.« less

A system for saccular intracranial aneurysm analysis and virtual stent planning

NASA Astrophysics Data System (ADS)

Baloch, Sajjad; Sudarsky, Sandra; Zhu, Ying; Mohamed, Ashraf; Geiger, Berhard; Dutta, Komal; Namburu, Durga; Nias, Puthenveettil; Martucci, Gary; Redel, Thomas

2012-02-01

Recent studies have found correlation between the risk of rupture of saccular aneurysms and their morphological characteristics, such as volume, surface area, neck length, among others. For reliably exploiting these parameters in endovascular treatment planning, it is crucial that they are accurately quantified. In this paper, we present a novel framework to assist physicians in accurately assessing saccular aneurysms and efficiently planning for endovascular intervention. The approach consists of automatically segmenting the pathological vessel, followed by the construction of its surface representation. The aneurysm is then separated from the vessel surface through a graph-cut based algorithm that is driven by local geometry as well as strong prior information. The corresponding healthy vessel is subsequently reconstructed and measurements representing the patient-specific geometric parameters of pathological vessel are computed. To better support clinical decisions on stenting and device type selection, the placement of virtual stent is eventually carried out in conformity with the shape of the diseased vessel using the patient-specific measurements. We have implemented the proposed methodology as a fully functional system, and extensively tested it with phantom and real datasets.

Video Guidance Sensor for Surface Mobility Operations

NASA Technical Reports Server (NTRS)

Fernandez, Kenneth R.; Fischer, Richard; Bryan, Thomas; Howell, Joe; Howard, Ricky; Peters, Bruce

2008-01-01

Robotic systems and surface mobility will play an increased role in future exploration missions. Unlike the LRV during Apollo era which was an astronaut piloted vehicle future systems will include teleoperated and semi-autonomous operations. The tasks given to these vehicles will run the range from infrastructure maintenance, ISRU, and construction to name a few. A common task that may be performed would be the retrieval and deployment of trailer mounted equipment. Operational scenarios may require these operations to be performed remotely via a teleoperated mode,or semi-autonomously. This presentation describes the on-going project to adapt the Automated Rendezvous and Capture (AR&C) sensor developed at the Marshall Space Flight Center for use in an automated trailer pick-up and deployment operation. The sensor which has been successfully demonstrated on-orbit has been mounted on an iRobot/John Deere RGATOR autonomous vehicle for this demonstration which will be completed in the March 2008 time-frame.

Superhydrophobic coated apparatus for liquid purification by evaporative condensation

DOEpatents

Simpson, John T; McNeany, Steve R; Dinsmore, Thomas V; Hunter, Scott R; Ivanov, Ilia N

2014-03-11

Disclosed are examples of apparatuses for evaporative purification of a contaminated liquid. In each example, there is a first vessel for storing the contaminated fluid. The first vessel includes a surface coated with a layer of superhydrophobic material and the surface is at least partially in contact with the contaminated liquid. The contaminants do not adhere to the surface as the purified liquid evaporates, thus simplifying maintenance of the apparatus.

Performance of a water suction system using hydrophilic fibrous cloth under low gravity and microgravity in parabolic flight.

PubMed

Tani, A; Saito, T; Kitaya, Y; Takahashi, H; Goto, E

2000-06-01

For suction of water from a water supply vessel including both water and air under microgravity and g-jitter conditions, a water suction system using hydrophilic fibrous cloth was developed and its performance was evaluated at 0.01-0.02 g-realized for 20 s by parabolic flight in an aircraft. Vessels used for the experiment were glass flasks and had a suction port for suction filtration. A piece of hydrophilic fibrous cloth was arranged along the inner surface of the vessels and the end was fixed to the suction port of the vessels. In vessel without hydrophilic cloths and containing 220 mL of water, the water did not move more than 5 mm along the inner surface and did not reach the suction port under low gravity. When hydrophilic cloths were used, on the other hand, water gathered onto the cloth surface, moved up along the cloth and reached the suction port under low gravity. The amount of water sucked from vessels varied with the amount of water in the vessel and the sectional area of hydrophilic cloths. When the vessels including both water and air were flown during parabolic flight (10(-4) g), water in the vessel moved along the cloth and a water film was formed on the cloth. These results indicated that it is possible to suck water using the fibrous cloth suction system under low gravity and microgravity conditions. Under low gravity conditions, it was difficult to suck water only. However, it is not necessary to separate water from air when the system is used for supplying water to plant root medium consisting of both liquid and gas phases.

46 CFR 28.515 - Submergence test as an alternative to stability calculations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... vessel must float with the lower end of the vessel not more than 12 inches (0.31 meters) below the water... described in paragraph (e) of this section must float in calm water, after being submerged for 18 hours, so that— (1) For an open vessel, any portion of the vessel's gunwale is above the water's surface; or (2...

Vessel contents of leaves after excision: a test of the Scholander assumption

Treesearch

Melvin T. Tyree; Herve Cochard

2003-01-01

When petioles of transpiring leaves are cut in the air, according to the 'Scholander assumption', the vessels cut open should fill with air as the water is drained away by tissue rehydration and/or continued transpiration. The distribution of air-filled vessels versus distance from the cut surface should match the distribution of lengths of 'open vessels...

Seismic attenuation system for a nuclear reactor

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

Liszkai, Tamas; Cadell, Seth

A system for attenuating seismic forces includes a reactor pressure vessel containing nuclear fuel and a containment vessel that houses the reactor pressure vessel. Both the reactor pressure vessel and the containment vessel include a bottom head. Additionally, the system includes a base support to contact a support surface on which the containment vessel is positioned in a substantially vertical orientation. An attenuation device is located between the bottom head of the reactor pressure vessel and the bottom head of the containment vessel. Seismic forces that travel from the base support to the reactor pressure vessel via the containment vesselmore » are attenuated by the attenuation device in a direction that is substantially lateral to the vertical orientation of the containment vessel.« less

Autonomous Surface Sample Acquisition for Planetary and Lunar Exploration

NASA Astrophysics Data System (ADS)

Barnes, D. P.

2007-08-01

Surface science sample acquisition is a critical activity within any planetary and lunar exploration mission, and our research is focused upon the design, implementation, experimentation and demonstration of an onboard autonomous surface sample acquisition capability for a rover equipped with a robotic arm upon which are mounted appropriate science instruments. Images captured by a rover stereo camera system can be processed using shape from stereo methods and a digital elevation model (DEM) generated. We have developed a terrain feature identification algorithm that can determine autonomously from DEM data suitable regions for instrument placement and/or surface sample acquisition. Once identified, surface normal data can be generated autonomously which are then used to calculate an arm trajectory for instrument placement and sample acquisition. Once an instrument placement and sample acquisition trajectory has been calculated, a collision detection algorithm is required to ensure the safe operation of the arm during sample acquisition.We have developed a novel adaptive 'bounding spheres' approach to this problem. Once potential science targets have been identified, and these are within the reach of the arm and will not cause any undesired collision, then the 'cost' of executing the sample acquisition activity is required. Such information which includes power expenditure and duration can be used to select the 'best' target from a set of potential targets. We have developed a science sample acquisition resource requirements calculation that utilises differential inverse kinematics methods to yield a high fidelity result, thus improving upon simple 1st order approximations. To test our algorithms a new Planetary Analogue Terrain (PAT) Laboratory has been created that has a terrain region composed of Mars Soil Simulant-D from DLR Germany, and rocks that have been fully characterised in the laboratory. These have been donated by the UK Planetary Analogue Field Study network, and constitute the science targets for our autonomous sample acquisition work. Our PAT Lab. terrain has been designed to support our new rover chassis which is based upon the ExoMars rover Concept-E mechanics which were investigated during the ESA ExoMars Phase A study. The rover has 6 wheel drives, 6 wheels steering, and a 6 wheel walking capability. Mounted on the rover chassis is the UWA robotic arm and mast. We have designed and built a PanCam system complete with a computer controlled pan and tilt mechanism. The UWA PanCam is based upon the ExoMars PanCam (Phase A study) and hence supports two Wide Angle Cameras (WAC - 64 degree FOV), and a High Resolution Camera (HRC - 5 degree FOV). WAC separation is 500 mm. Software has been developed to capture images which form the data input into our on-board autonomous surface sample acquisition algorithms.

Development of heat transfer enhancement techniques for external cooling of an advanced reactor vessel

NASA Astrophysics Data System (ADS)

Yang, Jun

Nucleate boiling is a well-recognized means for passively removing high heat loads (up to ˜106 W/m2) generated by a molten reactor core under severe accident conditions while maintaining relatively low reactor vessel temperature (<800 °C). With the upgrade and development of advanced power reactors, however, enhancing the nucleate boiling rate and its upper limit, Critical Heat Flux (CHF), becomes the key to the success of external passive cooling of reactor vessel undergoing core disrupture accidents. In the present study, two boiling heat transfer enhancement methods have been proposed, experimentally investigated and theoretically modelled. The first method involves the use of a suitable surface coating to enhance downward-facing boiling rate and CHF limit so as to substantially increase the possibility of reactor vessel surviving high thermal load attack. The second method involves the use of an enhanced vessel/insulation design to facilitate the process of steam venting through the annular channel formed between the reactor vessel and the insulation structure, which in turn would further enhance both the boiling rate and CHF limit. Among the various available surface coating techniques, metallic micro-porous layer surface coating has been identified as an appropriate coating material for use in External Reactor Vessel Cooling (ERVC) based on the overall consideration of enhanced performance, durability, the ease of manufacturing and application. Since no previous research work had explored the feasibility of applying such a metallic micro-porous layer surface coating on a large, downward facing and curved surface such as the bottom head of a reactor vessel, a series of characterization tests and experiments were performed in the present study to determine a suitable coating material composition and application method. Using the optimized metallic micro-porous surface coatings, quenching and steady-state boiling experiments were conducted in the Sub-scale Boundary Layer Boiling (SBLB) test facility at Penn State to investigate the nucleate boiling and CHF enhancement effects of the surface coatings by comparing the measurements with those for a plain vessel without coatings. An overall enhancement in nucleate boiling rates and CHF limits up to 100% were observed. Moreover, combination of data from quenching experiments and steady-state experiments produced new sets of boiling curves, which covered both the nucleate and transient boiling regimes with much greater accuracy. Beside the experimental work, a theoretical CHF model has also been developed by considering the vapor dynamics and the boiling-induced two-phase motions in three separate regions adjacent to the heating surface. The CHF model is capable of predicting the performance of micro-porous coatings with given particle diameter, porosity, media permeability and thickness. It is found that the present CHF model agrees favorably with the experimental data. Effects of an enhanced vessel/insulation structure on the local nucleate boiling rate and CHF limit have also been investigated experimentally. It is observed that the local two-phase flow quantities such as the local void fraction, quality, mean vapor velocity, mean liquid velocity, and mean vapor and liquid mass flow rates could have great impact on the local surface heat flux as boiling of water takes place on the vessel surface. An upward co-current two-phase flow model has been developed to predict the local two-phase flow behavior for different flow channel geometries, which are set by the design of insulation structures. It is found from the two-phase flow visualization experiments and the two-phase flow model calculations that the enhanced vessel/insulation structure greatly improved the steam venting process at the minimum gap location compared to the performance of thermal insulation structures without enhancement. Moveover, depending on the angular location, steady-state boiling experiments with the enhanced insulation design showed an enhancement of 1.8 to 3.0 times in the local critical heat flux. Finally, nucleate boiling and CHF correlations were developed based on the data obtained from various quenching and steady-state boiling experiments. Additionally, CHF enhancement factors were determined and examined to show the separate and integral effects of the two ERVC enhancement methods. When both vessel coating and insulation structure were used simultaneously, the integral effect on CHF enhancement was found much less than the product of the two separate effects, indicating possible competing mechanisms (i.e., interference) between the two enhancement methods.

Autonomic nervous system involvement in sickle cell disease.

PubMed

Coates, Thomas D; Chalacheva, Patjanaporn; Zeltzer, Lonnie; Khoo, Michael C K

2018-01-01

Sickle cell disease (SCD) is a genetic disorder of hemoglobin producing hemoglobin-S (HbS) and resulting in recurrent severe episodes of pain, organ damage and premature death due to vaso- occlusion. Deoxy HbS polymerizes, causing red cells to become rigid and lodge in the microvasculature if they do not escape into larger vessels before this transformation occurs. The mechanism that triggers this transition from steady state to vaso-occlusive crisis (VOC) is not known. Patients state that cold, emotional stress, and pain itself can trigger these events. In spite of the connection between these symptoms and the autonomic nervous system (ANS), and the fact that the ANS regulates regional microvascular blood flow, the role of the ANS in sickle pathophysiology has not been significantly investigated. We will briefly review the mechanism of SCD vaso-occlusion, the dysautonomia associated with SCD and sickle trait, and the role that the ANS may play in the genesis of sickle vaso-occlusive crisis.

Endothelial Cell Autonomous Role of Akt1: Regulation of Vascular Tone and Ischemia-Induced Arteriogenesis.

PubMed

Lee, Monica Y; Gamez-Mendez, Ana; Zhang, Jiasheng; Zhuang, Zhenwu; Vinyard, David J; Kraehling, Jan; Velazquez, Heino; Brudvig, Gary W; Kyriakides, Themis R; Simons, Michael; Sessa, William C

2018-04-01

The importance of PI3K/Akt signaling in the vasculature has been demonstrated in several models, as global loss of Akt1 results in impaired postnatal ischemia- and VEGF-induced angiogenesis. The ubiquitous expression of Akt1, however, raises the possibility of cell-type-dependent Akt1-driven actions, thereby necessitating tissue-specific characterization. Herein, we used an inducible, endothelial-specific Akt1-deleted adult mouse model (Akt1iECKO) to characterize the endothelial cell autonomous functions of Akt1 in the vascular system. Endothelial-targeted ablation of Akt1 reduces eNOS (endothelial nitric oxide synthase) phosphorylation and promotes both increased vascular contractility in isolated vessels and elevated diastolic blood pressures throughout the diurnal cycle in vivo. Furthermore, Akt1iECKO mice subject to the hindlimb ischemia model display impaired blood flow and decreased arteriogenesis. Endothelial Akt1 signaling is necessary for ischemic resolution post-injury and likely reflects the consequence of NO insufficiency critical for vascular repair. © 2018 American Heart Association, Inc.

Cutaneous sensory and autonomic denervation in CADASIL.

PubMed

Nolano, Maria; Provitera, Vincenzo; Donadio, Vincenzo; Caporaso, Giuseppe; Stancanelli, Annamaria; Califano, Francesca; Pianese, Luigi; Liguori, Rocco; Santoro, Lucio; Ragno, Michele

2016-03-15

To assess the involvement of the peripheral nervous system in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) by means of immunofluorescence and confocal analysis of punch skin biopsies. We recruited 14 unrelated patients with CADASIL (M/F = 9/5; age 53.9 ± 10.5 years) and 52 healthy controls (M/F = 31/21; age 53.8 ± 9.8). Patients underwent clinical and neuroradiologic assessment. Three-millimeter punch skin biopsies were taken from the fingertip, the thigh, and the distal leg and processed using indirect immunofluorescence and a panel of primary antibodies to mark vessels and sensory and autonomic nerve fibers. Intraepidermal nerve fibers (IENF), Meissner corpuscles (MC), and sudomotor, vasomotor, and pilomotor nerves were assessed using confocal microscopy. In patients, compared to controls, we found a severe loss of IENF at the distal leg (p < 0.01), at the thigh (p < 0.01), and at the fingertip (p < 0.01) with a non-length-dependent pattern and a loss of MC (p < 0.01). A severe sudomotor, vasomotor, and pilomotor nerve fiber loss was found by semiquantitative evaluation. Along with nerve loss, a severe derangement of the vascular bed was observed. In our patient population, sensory and autonomic denervation did not correlate with age, sex, type of mutation, or MRI involvement. We found an involvement of the peripheral nervous system in patients with CADASIL through the assessment of cutaneous somatic and autonomic nerves. The neurovascular derangement observed in the skin may reflect, although to a lesser extent, what happens in the CNS. © 2016 American Academy of Neurology.

HYDROBS: a long-term autonomous mooring for passive acoustic monitoring

NASA Astrophysics Data System (ADS)

Hello, Y.; Royer, J. Y.; Yegikyan, M.

2017-12-01

Passive acoustics proves an effective way for monitoring the low-level seismic activity of the ocean floor and low-frequency sounds from the ocean (baleen whales, sea-state, icebergs). Networks of synchronized autonomous hydrophones have thus been commonly deployed in the world ocean to monitor large sections of mid-oceanic ridges. HYDROBS is an improved system that meet two requirements: an easy access to the data collected by the instruments together with long-term deployments - up to 4 consecutive years - reducing the need of large vessels capable of yearly mooring operations in open seas. The system has two components: a data logger, up-to-date but similar to previous systems, and three messengers, releasable on demand to collect the data. The mooring line itself is classical, with an expandable weight at the sea-bottom to maintain the mooring, an acoustic release to free the mooring line for recovery, a line adjustable to the seafloor depth, and an immerged buoy, holding the acquisition system, to maintain the sensors at a constant depth and to bring the mooring line to the surface for its recovery. The data logger is based on a low-power microprocessor, an A/D-32bit convertor sampling at 250Hz, a 10-8 real time clock and SD card storage. Lithium batteries provide 3-4 years of autonomy. Acoustic communications with the surface-ship provide control over all functionalities at deployment and a health bulletin on demand. The 3 shuttles, encapsulated in 13" glass spheres, use the same CPU board and clock as the main station. Data transfer from the data logger to the shuttles is wireless (1Mbit/s digital inductive through water). Data are duplicated once per day on shuttles N and N+1 for redundancy. Prior to their release by acoustic command, the shuttles are synchronized with the master clock. At sea-surface, shuttles (as the main unit) look for GPS time and calculate their clock drift. So, the master clock drift can be monitored over time at every shuttle release until its final recovery. Shuttles and main unit are located on the sea-surface by AIS. Iridium communications can also be set to warn the user of a false release. A non-specialist can thus easily handle a shuttle recovery from a ship of opportunity. With 4-channels, this system is also suitable to monitor other parameters in the water column, continuously and over long periods.

40 CFR 61.275 - Periodic report.

Code of Federal Regulations, 2013 CFR

2013-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Benzene Emissions From Benzene Storage Vessels § 61.275 Periodic report. (a) The owner or operator of each storage vessel to... storage vessel in which: (i) The internal floating roof is not resting on the surface of the benzene...

40 CFR 61.275 - Periodic report.

Code of Federal Regulations, 2012 CFR

2012-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Benzene Emissions From Benzene Storage Vessels § 61.275 Periodic report. (a) The owner or operator of each storage vessel to... storage vessel in which: (i) The internal floating roof is not resting on the surface of the benzene...

40 CFR 61.275 - Periodic report.

Code of Federal Regulations, 2014 CFR

2014-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Benzene Emissions From Benzene Storage Vessels § 61.275 Periodic report. (a) The owner or operator of each storage vessel to... storage vessel in which: (i) The internal floating roof is not resting on the surface of the benzene...

40 CFR 61.275 - Periodic report.

Code of Federal Regulations, 2011 CFR

2011-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Benzene Emissions From Benzene Storage Vessels § 61.275 Periodic report. (a) The owner or operator of each storage vessel to... storage vessel in which: (i) The internal floating roof is not resting on the surface of the benzene...

Targeting Therapy Resistant Tumor Vessels

DTIC Science & Technology

2007-05-01

Porkka K, Laakko- nen P, Ruoslahti E. Nucleolin expressed at the cell surface is a marker of endothelial cells in angiogenic blood vessels. J Cell...anti-angiogenic therapy. Markers of such vessels will be useful in developing strategies for complete destruction of breast cancer vasculature, and in...express specific markers , and that these lymphatic markers are tumor type specific and distinct from blood vessel markers in the same tumors. The

[Key vessels assessment and operation highlights in laparoscopic extended right hemicolectomy].

PubMed

Wang, Hao; Zhao, Quanquan

2018-03-25

Laparoscopic radical colectomies have been more widely used gradually, among which laparoscopic extended right hemicolectomy is considered as the most difficult procedure. The difficulty of extended right hemicolectomy lies in the need to dissect lymph nodes along the superior mesenteric vein (SMV) and disconnect numerous and possible aberrant vessels. To address this problem, we emphasize two points in key vessel assessment: getting familiar with the anatomy along the medial-to-lateral approach and having a good understanding about the preoperative imaging presentations. An accurately preoperative imaging assessment by abdominal enhanced CT can help the surgeon understand the relative position of the key vessels to be dealt with during operation and the situation of the possible aberrant vessels so as to guide the procedure more effectively and facilitate the prevention and management of the intraoperative complications. During operation, the operator should pay special attention to the management of the vessels in the ileocolic vessel region, Henle's trunk and middle colon vessels. The operation highlights of the key vessels are as follows: (1) The ileocolic vessels: identifying the Toldt's gap correctly and opening the vascular sheath of the SMV securely; making sure that the duodenum is well protected. (2) Henle's trunk: dissecting along the surface of the Henle's trunk; preserving the anterior superior pancreaticoduodenal vein (ASPDV) and main trunk of the Henle's trunk; disconnecting the roots of the right colic vein (RCV) and right gastroepiploic vein (RGEV), and then dissecting lymph nodes along the surface of the pancreas. (3) The middle colon vessels: identifying the root of the middle colon vessel along the lower edge of the pancreas; avoiding entering behind the pancreas; mobilizing the transverse mesocolon sufficiently along the surface of the pancreas. Finally, we discuss and analyze the disputes currently existing in laparoscopic extended right hemicolectomy, including dissection of No.6 lymph nodes, naking the SMA and dissecting lymph nodes around the roots of the branches of SMA. This article shares our experience about laparoscopic extended right hemicolectomy, hoping that it could help beginners master the technique more safely and skillfully.

SAMOS - A Decade of High-Quality, Underway Meteorological and Oceanographic Data from Research Vessels

NASA Astrophysics Data System (ADS)

Smith, S. R.; Rolph, J.; Briggs, K.; Elya, J. L.; Bourassa, M. A.

2016-02-01

The authors will describe the successes and lessons learned from the Shipboard Automated Meteorological and Oceanographic System (SAMOS) initiative. Over the past decade, SAMOS has acquired, quality controlled, and distributed underway surface meteorological and oceanographic observations from nearly 40 oceanographic research vessels. Research vessels provide underway observations at high-temporal frequency (1-minute sampling interval) that include navigational (position, course, heading, and speed), meteorological (air temperature, humidity, wind, surface pressure, radiation, rainfall), and oceanographic (surface sea temperature and salinity) samples. Vessels recruited to the SAMOS initiative collect a high concentration of data within the U.S. continental shelf, around Hawaii and the islands of the tropical Pacific, and frequently operate well outside routine shipping lanes, capturing observations in extreme ocean environments (Southern, Arctic, South Atlantic, and South Pacific oceans) desired by the air-sea exchange, modeling, and satellite remote sensing communities. The presentation will highlight the data stewardship practices of the SAMOS initiative. Activities include routine automated and visual data quality evaluation, feedback to vessel technicians and operators regarding instrumentation errors, best practices for instrument siting and exposure on research vessels, and professional development activities for research vessel technicians. Best practices for data, metadata, and quality evaluation will be presented. We will discuss ongoing efforts to expand data services to enhance interoperability between marine data centers. Data access and archival protocols will also be presented, including how these data may be referenced and accessed via NCEI.

Secondary Impacts on Structures on the Lunar Surface

NASA Technical Reports Server (NTRS)

Christiansen, Eric; Walker, James D.; Grosch, Donald J.

2010-01-01

The Altair Lunar Lander is being designed for the planned return to the Moon by 2020. Since it is hoped that lander components will be re-used by later missions, studies are underway to examine the exposure threat to the lander sitting on the Lunar surface for extended periods. These threats involve both direct strikes of meteoroids on the vehicle as well as strikes from Lunar regolith and rock thrown by nearby meteorite strikes. Currently, the lander design is comprised of up to 10 different types of pressure vessels. These vessels included the manned habitation module, fuel, cryogenic fuel and gas storage containers, and instrument bays. These pressure vessels have various wall designs, including various aluminum alloys, honeycomb, and carbon-fiber composite materials. For some of the vessels, shielding is being considered. This program involved the test and analysis of six pressure vessel designs, one of which included a Whipple bumper shield. In addition to the pressure vessel walls, all the pressure vessels are wrapped in multi-layer insulation (MLI). Two variants were tested without the MLI to better understand the role of the MLI in the impact performance. The tests of performed were to examine the secondary impacts on these structures as they rested on the Lunar surface. If a hypervelocity meteor were to strike the surface nearby, it would throw regolith and rock debris into the structure at a much lower velocity. Also, when the manned module departs for the return to Earth, its rocket engines throw up debris that can impact the remaining lander components and cause damage. Glass spheres were used as a stimulant for the regolith material. Impact tests were performed with a gas gun to find the V50 of various sized spheres striking the pressure vessels. The impacts were then modeled and a fast-running approximate model for the V50 data was developed. This model was for performing risk analysis to assist in the vessel design and in the identification of ideal long-term mission sites. This paper reviews the impact tests and analysis and modeling examining the impact threat to various components in the lander design.

High-Aspect-Ratio Rotating Cell-Culture Vessel

NASA Technical Reports Server (NTRS)

Wolf, David A.; Sams, Clarence; Schwarz, Ray P.

1992-01-01

Cylindrical rotating cell-culture vessel with thin culture-medium layer of large surface area provides exchange of nutrients and products of metabolism with minimal agitation. Rotation causes averaging of buoyant forces otherwise separating components of different densities. Vessel enables growth of cells in homogeneous distribution with little agitation and little shear stress.

Resting spontaneous baroreflex sensitivity and cardiac autonomic control in anabolic androgenic steroid users

PubMed Central

dos Santos, Marcelo R.; Sayegh, Ana L.C.; Armani, Rafael; Costa-Hong, Valéria; de Souza, Francis R.; Toschi-Dias, Edgar; Bortolotto, Luiz A.; Yonamine, Mauricio; Negrão, Carlos E.; Alves, Maria-Janieire N.N.

2018-01-01

OBJECTIVES: Misuse of anabolic androgenic steroids in athletes is a strategy used to enhance strength and skeletal muscle hypertrophy. However, its abuse leads to an imbalance in muscle sympathetic nerve activity, increased vascular resistance, and increased blood pressure. However, the mechanisms underlying these alterations are still unknown. Therefore, we tested whether anabolic androgenic steroids could impair resting baroreflex sensitivity and cardiac sympathovagal control. In addition, we evaluate pulse wave velocity to ascertain the arterial stiffness of large vessels. METHODS: Fourteen male anabolic androgenic steroid users and 12 nonusers were studied. Heart rate, blood pressure, and respiratory rate were recorded. Baroreflex sensitivity was estimated by the sequence method, and cardiac autonomic control by analysis of the R-R interval. Pulse wave velocity was measured using a noninvasive automatic device. RESULTS: Mean spontaneous baroreflex sensitivity, baroreflex sensitivity to activation of the baroreceptors, and baroreflex sensitivity to deactivation of the baroreceptors were significantly lower in users than in nonusers. In the spectral analysis of heart rate variability, high frequency activity was lower, while low frequency activity was higher in users than in nonusers. Moreover, the sympathovagal balance was higher in users. Users showed higher pulse wave velocity than nonusers showing arterial stiffness of large vessels. Single linear regression analysis showed significant correlations between mean blood pressure and baroreflex sensitivity and pulse wave velocity. CONCLUSIONS: Our results provide evidence for lower baroreflex sensitivity and sympathovagal imbalance in anabolic androgenic steroid users. Moreover, anabolic androgenic steroid users showed arterial stiffness. Together, these alterations might be the mechanisms triggering the increased blood pressure in this population. PMID:29791601

Resting spontaneous baroreflex sensitivity and cardiac autonomic control in anabolic androgenic steroid users.

PubMed

Santos, Marcelo R Dos; Sayegh, Ana L C; Armani, Rafael; Costa-Hong, Valéria; Souza, Francis R de; Toschi-Dias, Edgar; Bortolotto, Luiz A; Yonamine, Mauricio; Negrão, Carlos E; Alves, Maria-Janieire N N

2018-05-21

Misuse of anabolic androgenic steroids in athletes is a strategy used to enhance strength and skeletal muscle hypertrophy. However, its abuse leads to an imbalance in muscle sympathetic nerve activity, increased vascular resistance, and increased blood pressure. However, the mechanisms underlying these alterations are still unknown. Therefore, we tested whether anabolic androgenic steroids could impair resting baroreflex sensitivity and cardiac sympathovagal control. In addition, we evaluate pulse wave velocity to ascertain the arterial stiffness of large vessels. Fourteen male anabolic androgenic steroid users and 12 nonusers were studied. Heart rate, blood pressure, and respiratory rate were recorded. Baroreflex sensitivity was estimated by the sequence method, and cardiac autonomic control by analysis of the R-R interval. Pulse wave velocity was measured using a noninvasive automatic device. Mean spontaneous baroreflex sensitivity, baroreflex sensitivity to activation of the baroreceptors, and baroreflex sensitivity to deactivation of the baroreceptors were significantly lower in users than in nonusers. In the spectral analysis of heart rate variability, high frequency activity was lower, while low frequency activity was higher in users than in nonusers. Moreover, the sympathovagal balance was higher in users. Users showed higher pulse wave velocity than nonusers showing arterial stiffness of large vessels. Single linear regression analysis showed significant correlations between mean blood pressure and baroreflex sensitivity and pulse wave velocity. Our results provide evidence for lower baroreflex sensitivity and sympathovagal imbalance in anabolic androgenic steroid users. Moreover, anabolic androgenic steroid users showed arterial stiffness. Together, these alterations might be the mechanisms triggering the increased blood pressure in this population.

Lymphatic drainage pathways from the cervix uteri: implications for radical hysterectomy?

PubMed

Kraima, A C; Derks, M; Smit, N N; Van Munsteren, J C; Van der Velden, J; Kenter, G G; DeRuiter, M C

2014-01-01

Radical hysterectomy with pelvic lymphadenectomy is the treatment of choice for early-stage cervical cancer. Wertheim's original technique has been often modified, mainly in the extent of parametrectomy. Okabayashi's technique is considered as the most radical variant regarding removal of the ventral parametrium and paracolpal tissues. Surgical outcome concerning recurrence and survival is good, but morbidity is high due to autonomic nerve damage. While the autonomic network has been studied extensively, the lymphatic system is less understood. This study describes the lymphatic drainage pathways of the cervix uteri and specifically the presence of lymphatics in the vesico-uterine ligament (VUL). A developmental series of 10 human female fetal pelves was studied. Paraffin embedded blocks were sliced in transverse sections of 8 or 10 μm. Analysis was performed by staining with antibodies against LYVE-1 (lymphatic endothelium), S100 (Schwann cells), alpha-Smooth Muscle Actin (smooth muscle cells) and CD68 (macrophages). The results were three-dimensionally represented. Two major pathways drained the cervix uteri: a supra-ureteral pathway, running in the cardinal ligament superior to the ureter, and a dorsal pathway, running in the utero-sacral ligament towards the rectal pillars. No lymph vessels draining the cervix uteri were detected in the VUL. In the paracolpal parametrium lymph vessels draining the upper vagina fused with those from the bladder. The VUL does not contain lymphatics from the cervix uteri. Hence, the favorable survival outcomes of the Okabayashi technique cannot be explained by radical removal of lymphatic pathways in the ventrocaudal parametrium. © 2013.

Estrogen replacement, vascular distensibility, and blood pressures in postmenopausal women.

PubMed

De Meersman, R E; Zion, A S; Giardina, E G; Weir, J P; Lieberman, J S; Downey, J A

1998-05-01

The pathogenesis of blood pressure (BP) rise in aging women remains unexplained, and one of the many incriminating factors may include abnormalities in arteriolar resistance vessels. The aim of this study was to determine the effects of unopposed estrogen on arteriolar distensibility, baroreceptor sensitivity (BRS), BP changes, and rate-pressure product (RPP). We tested the hypotheses that estrogen replacement therapy (ERT) enhances arteriolar distensibility and ameliorates BRS, which leads to decreases in BP and RPP. Postmenopausal women participated in a single-blind crossover study; the participants of this study, after baseline measurements, were randomly assigned to receive estrogen (ERT) or a drug-free treatment with a 6-wk washout period between treatments. The single-blind design was instituted because subjects become unblinded due to physiological changes (i.e., fluid shifts, weight gain, and secretory changes) associated with estrogen intake. However, investigators and technicians involved in data collection and analyses remained blind. After each treatment, subjects performed identical autonomic tests, during which electrocardiograms, beat-by-beat BPs, and respiration were recorded. The area under the dicrotic notch of the BP wave was used as an index of arteriolar distensibility. The magnitude of the reflex bradycardia after a precipitous rise in BP was used to determine BRS. Power spectral analysis of heart rate variability was used to assess autonomic activity. BPs were recorded from resistance vessels in the finger using a beat-by-beat photoplethysmographic device. RPP, a noninvasive marker of myocardial oxygen consumption, was calculated. Repeated-measures analyses of variance revealed a significantly enhanced arteriolar distensibility and BRS after ERT (P < 0.05). A trend of a lower sympathovagal balance at rest was observed after ERT, however, this trend did not reach statistical significance (P = 0.061) compared with the other treatments. The above autonomic changes produced significantly lower systolic and diastolic BP changes and RPPs (P < 0.05) at rest and during isometric exercise. We conclude that short-term unopposed ERT favorably enhances arteriolar distensibility, BRS, and hemodynamic parameters in postmenopausal women. These findings have clinical implications in the goals for treating cardiovascular risk factors in aging women.

Depolymerization-powered autonomous motors using biocompatible fuel.

PubMed

Zhang, Hua; Duan, Wentao; Liu, Lei; Sen, Ayusman

2013-10-23

We report the design of autonomous motors powered by the rapid depolymerization reaction of poly(2-ethyl cyanoacrylate) (PECA), an FDA-approved polymer. Motors were fabricated in two different length scales, 3 cm and 300 μm. The motion of the motors is induced by self-generated surface tension gradients along their bodies. The motors are capable of moving in various media, including salt solutions and artificial serum.

Cooperative Localization for Autonomous Underwater Vehicles

DTIC Science & Technology

2009-02-01

Another source of interference is the presence of background noise . Surface waves and marine mammals as well as the noise caused by the vehicle’s...opportunity to reach into other areas of ocean sciences by contributing to marine biology research. Her dedication along with the support from Mark Johnson...Algorithms 15 List of Acronyms 19 1 Introduction 23 1.1 Autonomous Marine Vehicles . . . . . . . . . . . . . . . . . . . . . . 25 1.1.1 Platforms

A new imaging technique based on resonance for arterial vessels

NASA Astrophysics Data System (ADS)

Zhang, Xiaoming; Fatemi, Mostafa; Greenleaf, James F.

2003-04-01

Vibro-acoustography is a new noncontact imaging method based on the radiation force of ultrasound. We extend this technique for imaging of arterial vessels based on vibration resonance. The arterial vessel is excited remotely by ultrasound at a resonant frequency, at which the vibration of the vessel as well as its transmission to the body surface are large enough to be measured. By scanning the ultrasound beam across the vessel plane and measuring the vibration at one single point on the body or vessel surface, an image of the interior artery can be mapped. Theory is developed that predicts the measured velocity is proportional to the value of the mode shape at resonance. Experimental studies were carried out on a silicone tube embedded in a cylindrical gel phantom of large radius, which simulates a large artery and the surrounding body. The fundamental frequency was measured at which the ultrasound transducer scanned across the tube plane with velocity measurement at one single point on the tube or on the phantom by laser. The images obtained show clearly the interior tube and the modal shape of the tube. The present technique offers a new imaging method for arterial vessels.

Self-propelled carbon nanotube based microrockets for rapid capture and isolation of circulating tumor cells

NASA Astrophysics Data System (ADS)

Banerjee, Shashwat S.; Jalota-Badhwar, Archana; Zope, Khushbu R.; Todkar, Kiran J.; Mascarenhas, Russel R.; Chate, Govind P.; Khutale, Ganesh V.; Bharde, Atul; Calderon, Marcelo; Khandare, Jayant J.

2015-05-01

Here, we report a non-invasive strategy for isolating cancer cells by autonomously propelled carbon nanotube (CNT) microrockets. H2O2-driven oxygen (O2) bubble-propelled microrockets were synthesized using CNT and Fe3O4 nanoparticles in the inner surface and covalently conjugating transferrin on the outer surface. Results show that self-propellant microrockets can specifically capture cancer cells.Here, we report a non-invasive strategy for isolating cancer cells by autonomously propelled carbon nanotube (CNT) microrockets. H2O2-driven oxygen (O2) bubble-propelled microrockets were synthesized using CNT and Fe3O4 nanoparticles in the inner surface and covalently conjugating transferrin on the outer surface. Results show that self-propellant microrockets can specifically capture cancer cells. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr01797a

Inspection of the interior surface of cylindrical vessels using optic fiber shearography

NASA Astrophysics Data System (ADS)

Liu, Bin; Wei, Quan; Tu, Jun; Arola, Dwayne D.; Zhang, Dongsheng

2017-09-01

In this study, a shearography system integrated with a coherent fiber-optic illumination and a fiber-optic imaging bundle is presented to inspect the quality of the interior surface of a cylindrical vessel for safety purposes. The specific optical arrangement is designed for the inspection of a certain area at a small working distance. The optical arrangement of the system was assembled and an aluminum honeycomb sample was evaluated to demonstrate the capability of the system. The important relationship between the image quality and the working distance, as well as the field of view, is discussed. The system has been applied for the inspection of the interior surface of a cylindrical vessel. The experimental results suggest that the shearography system integrated with optical and image fibers can effectively minimize the size of the inspection device and be capable of evaluating the interior surface of cylindrical structures.

Continuum mathematical modelling of pathological growth of blood vessels

NASA Astrophysics Data System (ADS)

Stadnik, N. E.; Dats, E. P.

2018-04-01

The present study is devoted to the mathematical modelling of a human blood vessel pathological growth. The vessels are simulated as the thin-walled circular tube. The boundary value problem of the surface growth of an elastic thin-walled cylinder is solved. The analytical solution is obtained in terms of velocities of stress strain state parameters. The condition of thinness allows us to study finite displacements of cylinder surfaces by means of infinitesimal deformations. The stress-strain state characteristics, which depend on the mechanical parameters of the biological processes, are numerically computed and graphically analysed.

46 CFR 154.7 - Definitions, acronyms, and terms.

Code of Federal Regulations, 2010 CFR

2010-10-01

... STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES General § 154.7 Definitions, acronyms... and to the outer surface of the hull in a ship with a shell of any other material. Cargo area means.... Existing gas vessel means a self-propelled vessel that— (a) Is delivered on or before October 31, 1976; or...

Vessel Biofouling Prevention and Management Options Report

DTIC Science & Technology

2015-03-01

Marine Reserve GNPD Galapagos National Park Directorate gpm Gallons per minute HST™ Hull Surface Treatment HullBUG Hull Bio -Mimetic Underwater...operators and hull cleaning equipment vendors. 2 VESSEL STRUCTURES SUBJECT TO BIOFOULING All submerged areas of the hull, including appendages and niche...categorized as proactive (preventative) and reactive (removal). Preventative measures include hull coatings that present bio -toxic surfaces to the immediate

Method of fabricating a prestressed cast iron vessel

DOEpatents

Lampe, Robert F.

1982-01-01

A method of fabricating a prestressed cast iron vessel wherein double wall cast iron body segments each have an arcuate inner wall and a spaced apart substantially parallel outer wall with a plurality of radially extending webs interconnecting the inner wall and the outer wall, the bottom surface and the two exposed radial side surfaces of each body segment are machined and eight body segments are formed into a ring. The top surfaces and outer surfaces of the outer walls are machined and keyways are provided across the juncture of adjacent end walls of the body segments. A liner segment complementary in shape to a selected inner wall of one of the body segments is mounted to each of the body segments and again formed into a ring. The liner segments of each ring are welded to form unitary liner rings and thereafter the cast iron body segments are prestressed to complete the ring assembly. Ring assemblies are stacked to form the vessel and adjacent unitary liner rings are welded. A top head covers the top ring assembly to close the vessel and axially extending tendons retain the top and bottom heads in place under pressure.

Minimal measures on surfaces of higher genus

NASA Astrophysics Data System (ADS)

Wang, Fang

We study the minimal measures for positive definite autonomous Lagrangian systems defined on the tangent bundles of compact surfaces with genus greater than one. We present some results on the structure of minimal measures on compact surfaces. Specifically, we give a finer description of the structure of minimal measures with rational rotation vectors for geodesic flows on compact surfaces.

Openings between Defective Endothelial Cells Explain Tumor Vessel Leakiness

PubMed Central

Hashizume, Hiroya; Baluk, Peter; Morikawa, Shunichi; McLean, John W.; Thurston, Gavin; Roberge, Sylvie; Jain, Rakesh K.; McDonald, Donald M.

2000-01-01

Leakiness of blood vessels in tumors may contribute to disease progression and is key to certain forms of cancer therapy, but the structural basis of the leakiness is unclear. We sought to determine whether endothelial gaps or transcellular holes, similar to those found in leaky vessels in inflammation, could explain the leakiness of tumor vessels. Blood vessels in MCa-IV mouse mammary carcinomas, which are known to be unusually leaky (functional pore size 1.2–2 μm), were compared to vessels in three less leaky tumors and normal mammary glands. Vessels were identified by their binding of intravascularly injected fluorescent cationic liposomes and Lycopersicon esculentum lectin and by CD31 (PECAM) immunoreactivity. The luminal surface of vessels in all four tumors had a defective endothelial monolayer as revealed by scanning electron microscopy. In MCa-IV tumors, 14% of the vessel surface was lined by poorly connected, overlapping cells. The most superficial lining cells, like endothelial cells, had CD31 immunoreactivity and fenestrae with diaphragms, but they had a branched phenotype with cytoplasmic projections as long as 50 μm. Some branched cells were separated by intercellular openings (mean diameter 1.7 μm; range, 0.3–4.7 μm). Transcellular holes (mean diameter 0.6 μm) were also present but were only 8% as numerous as intercellular openings. Some CD31-positive cells protruded into the vessel lumen; others sprouted into perivascular tumor tissue. Tumors in RIP-Tag2 mice had, in addition, tumor cell-lined lakes of extravasated erythrocytes. We conclude that some tumor vessels have a defective cellular lining composed of disorganized, loosely connected, branched, overlapping or sprouting endothelial cells. Openings between these cells contribute to tumor vessel leakiness and may permit access of macromolecular therapeutic agents to tumor cells. PMID:10751361

Laser Range and Bearing Finder for Autonomous Missions

NASA Technical Reports Server (NTRS)

Granade, Stephen R.

2004-01-01

NASA has recently re-confirmed their interest in autonomous systems as an enabling technology for future missions. In order for autonomous missions to be possible, highly-capable relative sensor systems are needed to determine an object's distance, direction, and orientation. This is true whether the mission is autonomous in-space assembly, rendezvous and docking, or rover surface navigation. Advanced Optical Systems, Inc. has developed a wide-angle laser range and bearing finder (RBF) for autonomous space missions. The laser RBF has a number of features that make it well-suited for autonomous missions. It has an operating range of 10 m to 5 km, with a 5 deg field of view. Its wide field of view removes the need for scanning systems such as gimbals, eliminating moving parts and making the sensor simpler and space qualification easier. Its range accuracy is 1% or better. It is designed to operate either as a stand-alone sensor or in tandem with a sensor that returns range, bearing, and orientation at close ranges, such as NASA's Advanced Video Guidance Sensor. We have assembled the initial prototype and are currently testing it. We will discuss the laser RBF's design and specifications. Keywords: laser range and bearing finder, autonomous rendezvous and docking, space sensors, on-orbit sensors, advanced video guidance sensor

Autonomous Landing and Hazard Avoidance Technology (ALHAT)

NASA Technical Reports Server (NTRS)

Epp, Chirold

2007-01-01

This viewgraph presentation reviews the work towards technology that will result in an autonomous landing on the lunar surface, that will avoid the hazards of lunar landing. In October 2005, the Exploration Systems Mission Directorate at NASA Headquarters assigned the development of new technologies to support the return to the moon. One of these was Autonomous Precision Landing and Hazard Detection and Avoidance Technology now known as ALHAT ALHAT is a lunar descent and landing GNC technology development project led by Johnson Space Center (JSC) with team members from Langley Research Center (LaRC), Jet Propulsion Laboratory (JPL), Draper Laboratories (CSDL) and the Applied Physics Laboratory (APL)

Americium behaviour in plastic vessels.

PubMed

Legarda, F; Herranz, M; Idoeta, R; Abelairas, A

2010-01-01

The adsorption of (241)Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of (241)Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of (241)Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification. Copyright 2009 Elsevier Ltd. All rights reserved.

Multi-agent autonomous system

NASA Technical Reports Server (NTRS)

Fink, Wolfgang (Inventor); Dohm, James (Inventor); Tarbell, Mark A. (Inventor)

2010-01-01

A multi-agent autonomous system for exploration of hazardous or inaccessible locations. The multi-agent autonomous system includes simple surface-based agents or craft controlled by an airborne tracking and command system. The airborne tracking and command system includes an instrument suite used to image an operational area and any craft deployed within the operational area. The image data is used to identify the craft, targets for exploration, and obstacles in the operational area. The tracking and command system determines paths for the surface-based craft using the identified targets and obstacles and commands the craft using simple movement commands to move through the operational area to the targets while avoiding the obstacles. Each craft includes its own instrument suite to collect information about the operational area that is transmitted back to the tracking and command system. The tracking and command system may be further coupled to a satellite system to provide additional image information about the operational area and provide operational and location commands to the tracking and command system.

Electron tube

DOEpatents

Suyama, Motohiro [Hamamatsu, JP; Fukasawa, Atsuhito [Hamamatsu, JP; Arisaka, Katsushi [Los Angeles, CA; Wang, Hanguo [North Hills, CA

2011-12-20

An electron tube of the present invention includes: a vacuum vessel including a face plate portion made of synthetic silica and having a surface on which a photoelectric surface is provided, a stem portion arranged facing the photoelectric surface and made of synthetic silica, and a side tube portion having one end connected to the face plate portion and the other end connected to the stem portion and made of synthetic silica; a projection portion arranged in the vacuum vessel, extending from the stem portion toward the photoelectric surface, and made of synthetic silica; and an electron detector arranged on the projection portion, for detecting electrons from the photoelectric surface, and made of silicon.

Improved fluid dynamics similarity, analysis and verification. Part 5: Analytical and experimental studies of thermal stratification phenomena

NASA Technical Reports Server (NTRS)

Winter, E. R. F.; Schoenhals, R. J.; Haug, R. I.; Libby, T. L.; Nelson, R. N.; Stevenson, W. H.

1968-01-01

The stratification behavior of a contained fluid subjected to transient free convection heat transfer was studied. A rectangular vessel was employed with heat transfer from two opposite walls of the vessel to the fluid. The wall temperature was increased suddenly to initiate the process and was then maintained constant throughout the transient stratification period. Thermocouples were positioned on a post at the center of the vessel. They were adjusted so that temperatures could be measured at the fluid surface and at specific depths beneath the surface. The predicted values of the surface temperature and the stratified layer thickness were found to agree reasonably well with the experimental measurements. The experiments also provided information on the transient centerline temperature distribution and the transient flow distribution.

Vision Based Autonomous Robotic Control for Advanced Inspection and Repair

NASA Technical Reports Server (NTRS)

Wehner, Walter S.

2014-01-01

The advanced inspection system is an autonomous control and analysis system that improves the inspection and remediation operations for ground and surface systems. It uses optical imaging technology with intelligent computer vision algorithms to analyze physical features of the real-world environment to make decisions and learn from experience. The advanced inspection system plans to control a robotic manipulator arm, an unmanned ground vehicle and cameras remotely, automatically and autonomously. There are many computer vision, image processing and machine learning techniques available as open source for using vision as a sensory feedback in decision-making and autonomous robotic movement. My responsibilities for the advanced inspection system are to create a software architecture that integrates and provides a framework for all the different subsystem components; identify open-source algorithms and techniques; and integrate robot hardware.

Metal vapor vacuum arc switching - Applications and results. [for launchers

NASA Technical Reports Server (NTRS)

Cope, D.; Mongeau, P.

1984-01-01

The design of metal-vapor vacuum-arc switches (MVSs) for electromagnetic launchers is discussed, and preliminary results are presented for an experimental MVS. The general principles of triggered-vacuum-gap and vacuum-interrupter MVSs are reviewed, and the requirements of electromagnetic launchers are analyzed. High-current design problems such as electrode erosion, current sharing, magnetic effects, and thermal effects are examined. The experimental MVS employs stainless-steel flanges, a glass vacuum vessel, an adjustable electrode gap, autonomous internal magnetic-field coils, and a tungsten-pin trigger assembly. Some results from tests without magnetic augmentation are presented graphically.

Software Architecture for Anti-Submarine Warfare Unmanned Surface Vehicles

DTIC Science & Technology

2016-09-01

discussion about software systems that could be used to control these systems to make the jobs of the human operators easier. B. RESEARCH QUESTIONS... research study. To better understand the role of artificial intelligence in designing autonomous systems, S. Russell and P. Norvig jointly authored a...artificial intelligence, and autonomous systems. This serves as the framework for the real design challenge. 1. Protecting the Battle Group The United

Integrated synoptic surveys using an autonomous underwater vehicle and manned boats

USGS Publications Warehouse

Jackson, P. Ryan

2013-01-01

Traditional surface-water surveys are being combined with autonomous technology to produce integrated surveys of bathymetry, water quality, and velocity in inland lakes and reservoirs. This new technology provides valuable, high-resolution, integrated data that allow a systems-based approach to understanding common environmental problems. This fact sheet presents several example applications of integrated surveys within inland lakes and coastal Lake Michigan and Lake Erie.

Identification and characterization of a resident vascular stem/progenitor cell population in preexisting blood vessels

PubMed Central

Naito, Hisamichi; Kidoya, Hiroyasu; Sakimoto, Susumu; Wakabayashi, Taku; Takakura, Nobuyuki

2012-01-01

Vasculogenesis, the in-situ assembly of angioblast or endothelial progenitor cells (EPCs), may persist into adult life, contributing to new blood vessel formation. However, EPCs are scattered throughout newly developed blood vessels and cannot be solely responsible for vascularization. Here, we identify an endothelial progenitor/stem-like population located at the inner surface of preexisting blood vessels using the Hoechst method in which stem cell populations are identified as side populations. This population is dormant in the steady state but possesses colony-forming ability, produces large numbers of endothelial cells (ECs) and when transplanted into ischaemic lesions, restores blood flow completely and reconstitutes de-novo long-term surviving blood vessels. Moreover, although surface markers of this population are very similar to conventional ECs, and they reside in the capillary endothelium sub-population, the gene expression profile is completely different. Our results suggest that this heterogeneity of stem-like ECs will lead to the identification of new targets for vascular regeneration therapy. PMID:22179698

46 CFR 28.875 - Radar, depth sounding, and auto-pilot.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 1 2011-10-01 2011-10-01 false Radar, depth sounding, and auto-pilot. 28.875 Section 28... COMMERCIAL FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels § 28.875 Radar, depth sounding, and auto-pilot. (a) Each vessel must be fitted with a general marine radar system for surface navigation with a radar...

Development of a Vision-Based Situational Awareness Capability for Unmanned Surface Vessels

DTIC Science & Technology

2017-09-01

used to provide an SA capability for USVs. This thesis addresses the following research questions: (1) Can a computer vision– based technique be...BLANK 51 VI. CONCLUSION AND RECOMMENDATIONS A. CONCLUSION This research demonstrated the feasibility of using a computer vision– based ...VISION- BASED SITUATIONAL AWARENESS CAPABILITY FOR UNMANNED SURFACE VESSELS by Ying Jie Benjemin Toh September 2017 Thesis Advisor: Oleg

Space environmental considerations for a long-term cryogenic storage vessel

NASA Technical Reports Server (NTRS)

Nakanishi, Shigeo

1987-01-01

Information is given on the kind of protection that is needed against impact and perforation of a long-term cryogenic storage vessel in space by meteoroids and space debris. The long-term effects of the space environment on thermal control surfaces and coatings, and the question of whether the insulation and thermal control surfaces should be encased in a vacuum jacket shell are discussed.

In vivo, high-resolution, three-dimensional imaging of port wine stain microvasculature in human skin.

PubMed

Liu, Gangjun; Jia, Wangcun; Nelson, J Stuart; Chen, Zhongping

2013-12-01

Port-wine stain (PWS) is a congenital, progressive vascular malformation of the dermis. The use of optical coherence tomography (OCT) for the characterization of blood vessels in PWS skin has been demonstrated by several groups. In the past few years, advances in OCT technology have greatly increased imaging speed. Sophisticated numerical algorithms have improved the sensitivity of Doppler OCT dramatically. These improvements have enabled the noninvasive, high-resolution, three-dimensional functional imaging of PWS skin. Here, we demonstrate high-resolution, three-dimensional, microvasculature imaging of PWS and normal skin using Doppler OCT technique. The OCT system uses a swept source laser which has a central wavelength of 1,310 nm, an A-line rate of 50 kHz and a total average power of 16 mW. The system uses a handheld imaging probe and has an axial resolution of 9.3 µm in air and a lateral resolution of approximately 15 µm. Images were acquired from PWS subjects at the Beckman Laser Institute and Medical Clinic. Microvasculature of the PWS skin and normal skin were obtained from the PWS subject. High-resolution, three-dimensional microvasculature of PWS and normal skin were obtained. Many enlarged PWS vessels are detected in the dermis down to 1.0 mm below the PWS skin surface. In one subject, the blood vessel diameters range from 40 to 90 µm at the epidermal-dermal junction and increase up to 300-500 µm at deeper regions 700-1,000 µm below skin surface. The blood vessels close to the epidermal-dermal junction are more uniform, in terms of diameter. The more tortuous and dilated PWS blood vessels are located at deeper regions 600-1,000 µm below the skin surface. In another subject example, the PWS skin blood vessels are dilated at very superficial layers at a depth less than 500 µm below the skin surface. The PWS skin vessel diameters range from 60 to 650 µm, with most vessels having a diameter of around 200 µm. OCT can be used to quantitatively image in vivo skin micro-vasculature. Analysis of the PWS and normal skin blood vessels were performed and the results can provide quantitative information to optimize laser treatment on an individual patient basis. © 2013 Wiley Periodicals, Inc.

Optical mass gauge sensor having an energy per unit area of illumination detection

NASA Technical Reports Server (NTRS)

Justak, John F. (Inventor)

2000-01-01

An optical mass gauge sensor is disclosed comprising a vessel having an interior surface which reflects radiant energy at a wavelength at least partially absorbed by a fluid contained within the vessel, an illuminating device for introducing radiant energy at such wavelength into the vessel interior, and, a detector for measuring the energy per unit area of illumination within the vessel created by the radiant energy which is not absorbed by the fluid.

Method for accurate sizing of pulmonary vessels from 3D medical images

NASA Astrophysics Data System (ADS)

O'Dell, Walter G.

2015-03-01

Detailed characterization of vascular anatomy, in particular the quantification of changes in the distribution of vessel sizes and of vascular pruning, is essential for the diagnosis and management of a variety of pulmonary vascular diseases and for the care of cancer survivors who have received radiation to the thorax. Clinical estimates of vessel radii are typically based on setting a pixel intensity threshold and counting how many "On" pixels are present across the vessel cross-section. A more objective approach introduced recently involves fitting the image with a library of spherical Gaussian filters and utilizing the size of the best matching filter as the estimate of vessel diameter. However, both these approaches have significant accuracy limitations including mis-match between a Gaussian intensity distribution and that of real vessels. Here we introduce and demonstrate a novel approach for accurate vessel sizing using 3D appearance models of a tubular structure along a curvilinear trajectory in 3D space. The vessel branch trajectories are represented with cubic Hermite splines and the tubular branch surfaces represented as a finite element surface mesh. An iterative parameter adjustment scheme is employed to optimally match the appearance models to a patient's chest X-ray computed tomography (CT) scan to generate estimates for branch radii and trajectories with subpixel resolution. The method is demonstrated on pulmonary vasculature in an adult human CT scan, and on 2D simulated test cases.

CHF Enhancement by Vessel Coating for External Reactor Vessel Cooling

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

Fan-Bill Cheung; Joy L. Rempe

2004-06-01

In-vessel retention (IVR) is a key severe accident management (SAM) strategy that has been adopted by some operating nuclear power plants and advanced light water reactors (ALWRs). One viable means for IVR is the method of external reactor vessel cooling (ERVC) by flooding of the reactor cavity during a severe accident. As part of a joint Korean – United States International Nuclear Energy Research Initiative (K-INERI), an experimental study has been conducted to investigate the viability of using an appropriate vessel coating to enhance the critical heat flux (CHF) limits during ERVC. Toward this end, transient quenching and steady-state boilingmore » experiments were performed in the SBLB (Subscale Boundary Layer Boiling) facility at Penn State using test vessels with micro-porous aluminum coatings. Local boiling curves and CHF limits were obtained in these experiments. When compared to the corresponding data without coatings, substantial enhancement in the local CHF limits for the case with surface coatings was observed. Results of the steady state boiling experiments showed that micro-porous aluminum coatings were very durable. Even after many cycles of steady state boiling, the vessel coatings remained rather intact, with no apparent changes in color or structure. Moreover, the heat transfer performance of the coatings was found to be highly desirable with an appreciable CHF enhancement in all locations on the vessel outer surface but with very little effect of aging.« less

Presence of MUC4 in human milk and at the luminal surfaces of blood vessels.

PubMed

Zhang, Jin; Perez, Aymee; Yasin, Mohammad; Soto, Pedro; Rong, Min; Theodoropoulos, George; Carothers Carraway, Coralie A; Carraway, Kermit L

2005-07-01

MUC4 is a heterodimeric membrane mucin, composed of a mucin subunit ASGP-1 (MUC4alpha) and a transmembrane subunit ASGP-2 (MUC4beta), which has been implicated in the protection of epithelial cell surfaces. Surprisingly, development and characterization of a new monoclonal antibody (mAb), called 1G8, against ASGP-2 demonstrated by immunohistochemistry the presence of MUC4 at the luminal surfaces of blood vessels of both normal tissues and tumors. Muc4 was detected with 1G8 and other Muc4 antibodies in blood vessels from humans, rats and mice. This expression of MUC4 in endothelial cells was confirmed by immunoblotting with 1G8 in human umbilical vein endothelial cells (HUVECs), human iliac artery endothelial cells (HIAECs), and human microvascular endothelial cells (HMVECs). MUC4 could be observed on HUVECs grown on either plastic or Matrigel. Finally, MUC4 expression in the three types of endothelial cell lines was confirmed by reverse transcription-polymerase chain reaction (RT-PCR). These results provide, to our knowledge, the first demonstration of a member of the MUC gene family and membrane mucin in blood vessels. As a luminal surface component, the MUC4 is situated to contribute to the non-adhesive luminal surface and to act as an intrinsic protection and survival factor. (c) 2004 Wiley-Liss, Inc.

Attrition reactor system

DOEpatents

Scott, Charles D.; Davison, Brian H.

1993-01-01

A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur.

Liners for ion transport membrane systems

DOEpatents

Carolan, Michael Francis; Miller, Christopher Francis

2010-08-10

Ion transport membrane system comprising (a) a pressure vessel comprising an interior, an exterior, an inlet, an inlet conduit, an outlet, and an outlet conduit; (b) a plurality of planar ion transport membrane modules disposed in the interior of the pressure vessel and arranged in series, each membrane module comprising mixed metal oxide ceramic material and having an interior region and an exterior region, wherein the inlet and the outlet of the pressure vessel are in flow communication with exterior regions of the membrane modules; (c) a gas manifold having an interior surface wherein the gas manifold is in flow communication with the interior region of each of the planar ion transport membrane modules and with the exterior of the pressure vessel; and (d) a liner disposed within any of the inlet conduit, the outlet conduit, and the interior surface of the gas manifold.

A Conceptual Study for the Autonomous Direct Forming of Lunar Regolith into Flexlock (Trademark) Geomats for Lunar Surface Operations

NASA Technical Reports Server (NTRS)

Robertson, Luke B.; Hintze, Paul; OConnor, Gregory W.

2009-01-01

We describe the conceptual method of an autonomously operable Direct Forming machine that would consume regolith or regolith slag to mold intimately, interlinked elements in a continuous process. The resulting product, one to three meter wide geomats, would be deployed over commonly traversed areas to isolate the astronauts and equipment from underlying dust. The porous geotextile would provide areas for dust settling, thereby mitigating dust impingement on astronaut suits or surface structures. Because of their self-supporting yet flexible structure, these geomats could be assembled into shields and buttresses to protect lunar habitants from radiation, forming a "flexoskeleton" from in situ materials.

DNA "nano-claw": logic-based autonomous cancer targeting and therapy.

PubMed

You, Mingxu; Peng, Lu; Shao, Na; Zhang, Liqin; Qiu, Liping; Cui, Cheng; Tan, Weihong

2014-01-29

Cell types, both healthy and diseased, can be classified by inventories of their cell-surface markers. Programmable analysis of multiple markers would enable clinicians to develop a comprehensive disease profile, leading to more accurate diagnosis and intervention. As a first step to accomplish this, we have designed a DNA-based device, called "Nano-Claw". Combining the special structure-switching properties of DNA aptamers with toehold-mediated strand displacement reactions, this claw is capable of performing autonomous logic-based analysis of multiple cancer cell-surface markers and, in response, producing a diagnostic signal and/or targeted photodynamic therapy. We anticipate that this design can be widely applied in facilitating basic biomedical research, accurate disease diagnosis, and effective therapy.

Autonomous Navigation Error Propagation Assessment for Lunar Surface Mobility Applications

NASA Technical Reports Server (NTRS)

Welch, Bryan W.; Connolly, Joseph W.

2006-01-01

The NASA Vision for Space Exploration is focused on the return of astronauts to the Moon. While navigation systems have already been proven in the Apollo missions to the moon, the current exploration campaign will involve more extensive and extended missions requiring new concepts for lunar navigation. In this document, the results of an autonomous navigation error propagation assessment are provided. The analysis is intended to be the baseline error propagation analysis for which Earth-based and Lunar-based radiometric data are added to compare these different architecture schemes, and quantify the benefits of an integrated approach, in how they can handle lunar surface mobility applications when near the Lunar South pole or on the Lunar Farside.

Proceedings of the 8th Annual Summer Conference: NASA/USRA Advanced Design Program

NASA Technical Reports Server (NTRS)

1992-01-01

Papers presented at the 8th Annual Summer Conference are categorized as Space Projects and Aeronautics projects. Topics covered include: Systematic Propulsion Optimization Tools (SPOT), Assured Crew Return Vehicle Post Landing Configuration Design and Test, Autonomous Support for Microorganism Research in Space, Bioregenerative System Components for Microgravity, The Extended Mission Rover (EMR), Planetary Surface Exploration MESUR/Autonomous Lunar Rover, Automation of Closed Environments in Space for Human Comfort and Safety, Walking Robot Design, Extraterrestrial Surface Propulsion Systems, The Design of Four Hypersonic Reconnaissance Aircraft, Design of a Refueling Tanker Delivering Liquid Hydrogen, The Design of a Long-Range Megatransport Aircraft, and Solar Powered Multipurpose Remotely Powered Aircraft.

Regolith Advanced Surface Systems Operations Robot (RASSOR) Phase 2 and Smart Autonomous Sand-Swimming Excavator

NASA Technical Reports Server (NTRS)

Sandy, Michael

2015-01-01

The Regolith Advanced Surface Systems Operations Robot (RASSOR) Phase 2 is an excavation robot for mining regolith on a planet like Mars. The robot is programmed using the Robotic Operating System (ROS) and it also uses a physical simulation program called Gazebo. This internship focused on various functions of the program in order to make it a more professional and efficient robot. During the internship another project called the Smart Autonomous Sand-Swimming Excavator was worked on. This is a robot that is designed to dig through sand and extract sample material. The intern worked on programming the Sand-Swimming robot, and designing the electrical system to power and control the robot.

Autoantibody-mediated bowel and bladder dysfunction in a patient with chronic, nondiabetic neuropathy.

PubMed

Jackson, Michael W; Gordon, Thomas P; McCombe, Pamela A

2008-04-01

Physiological techniques can be used to detect novel autoantibodies causing alteration of autonomic function after passive transfer to mice. Previously, such antibodies have been detected in patients with type I diabetes mellitus, myasthenia gravis, and Sjogren's syndrome. We now describe a patient with an idiopathic nondiabetic neuropathy with prominent autonomic symptoms, including bladder and bowel dysfunction. Physiological assays of whole colon and bladder were used to determine the presence in the patient serum of functional autoantibodies capable of mediating autonomic dysfunction. Immunoglobulin G (IgG) from this patient was able to disrupt bladder and bowel function on passive transfer to mice. This is a new pattern of autoantibody-mediated abnormality. Although the target antigen is unknown, it is likely to be a cell-surface receptor or ion channel. This case highlights the usefulness of passive transfer studies in detecting functional antibodies in patients with autonomic neuropathy.

ALHAT: Autonomous Landing and Hazard Avoidance Technology

NASA Technical Reports Server (NTRS)

Robertson, Edward A.; Carson, John M., III

2015-01-01

The ALHAT project was chartered by NASA HQ in 2006 to develop and mature to TRL 6 an autonomous lunar landing GN&C and sensing system for crewed, cargo, and robotic planetary landing vehicles. The multi-center ALHAT team was tasked with providing a system capable of identifying and avoiding surface hazards in real time to enable safe precision landing to within tens of meters of a designated planetary landing site under any lighting conditions.

Bolts from Orion: Destroying Mobile Surface-to-Air Missile Systems with Lethal Autonomous Aircraft

DTIC Science & Technology

2016-07-01

era SAMs that had been upgraded by Ukrainian contractors . During the operation, Russian aircraft’s 10 electronic countermeasures could not...main SEAD asset is the F-16 CJ equipped with the HARM targeting system ( HTS ). The HTS can autonomously locate and identify threat radars and pass...targeting information to the HARMs before launch. The HTS can also provide targeting 13 information to global positioning system (GPS) guided

Reactor vessel using metal oxide ceramic membranes

DOEpatents

Anderson, Marc A.; Zeltner, Walter A.

1992-08-11

A reaction vessel for use in photoelectrochemical reactions includes as its reactive surface a metal oxide porous ceramic membrane of a catalytic metal such as titanium. The reaction vessel includes a light source and a counter electrode. A provision for applying an electrical bias between the membrane and the counter electrode permits the Fermi levels of potential reaction to be favored so that certain reactions may be favored in the vessel. The electrical biasing is also useful for the cleaning of the catalytic membrane.

S1P1 inhibits sprouting angiogenesis during vascular development.

PubMed

Ben Shoham, Adi; Malkinson, Guy; Krief, Sharon; Shwartz, Yulia; Ely, Yona; Ferrara, Napoleone; Yaniv, Karina; Zelzer, Elazar

2012-10-01

Coordination between the vascular system and forming organs is essential for proper embryonic development. The vasculature expands by sprouting angiogenesis, during which tip cells form filopodia that incorporate into capillary loops. Although several molecules, such as vascular endothelial growth factor A (Vegfa), are known to induce sprouting, the mechanism that terminates this process to ensure neovessel stability is still unknown. Sphingosine-1-phosphate receptor 1 (S1P(1)) has been shown to mediate interaction between endothelial and mural cells during vascular maturation. In vitro studies have identified S1P(1) as a pro-angiogenic factor. Here, we show that S1P(1) acts as an endothelial cell (EC)-autonomous negative regulator of sprouting angiogenesis during vascular development. Severe aberrations in vessel size and excessive sprouting found in limbs of S1P(1)-null mouse embryos before vessel maturation imply a previously unknown, mural cell-independent role for S1P(1) as an anti-angiogenic factor. A similar phenotype observed when S1P(1) expression was blocked specifically in ECs indicates that the effect of S1P(1) on sprouting is EC-autonomous. Comparable vascular abnormalities in S1p(1) knockdown zebrafish embryos suggest cross-species evolutionary conservation of this mechanism. Finally, genetic interaction between S1P(1) and Vegfa suggests that these factors interplay to regulate vascular development, as Vegfa promotes sprouting whereas S1P(1) inhibits it to prevent excessive sprouting and fusion of neovessels. More broadly, because S1P, the ligand of S1P(1), is blood-borne, our findings suggest a new mode of regulation of angiogenesis, whereby blood flow closes a negative feedback loop that inhibits sprouting angiogenesis once the vascular bed is established and functional.

Dynamic article: surgical anatomical planes for complete mesocolic excision and applied vascular anatomy of the right colon.

PubMed

Açar, Halil İbrahim; Cömert, Ayhan; Avşar, Abdullah; Çelik, Safa; Kuzu, Mehmet Ayhan

2014-10-01

Lower local recurrence rates and better overall survival are associated with complete mesocolic excision with central vascular ligation for treatment of colon cancer. To accomplish this, surgeons need to pay special attention to the surgical anatomical planes and vascular anatomy of the colon. However, surgical education in this area has been neglected. The aim of this study is to define the correct surgical anatomical planes for complete mesocolic excision with central vascular ligation and to demonstrate the correct dissection technique for protecting anatomical structures. Macroscopic and microscopic surgical dissections were performed on 12 cadavers in the anatomy laboratory and on autopsy specimens. The dissections were recorded as video clips. Dissections were performed in accordance with the complete mesocolic excision technique on 10 male and 2 female cadavers. Vascular structures, autonomic nerves, and related fascias were shown. Within each step of the surgical procedure, important anatomical structures were displayed on still images captured from videos by animations. Three crucial steps for complete mesocolic excision with central vascular ligation are demonstrated on the cadavers: 1) full mobilization of the superior mesenteric root following the embryological planes between the visceral and the parietal fascias; 2) mobilization of the mesocolon from the duodenum and the pancreas and identification of vascular structures, especially the veins around the pancreas; and 3) central vascular ligation of the colonic vessels at their origin, taking into account the vascular variations within the mesocolonic vessels and the autonomic nerves around the superior mesenteric artery. The limitation of this study was the number of the cadavers used. Successful complete mesocolic excision with central vascular ligation depends on an accurate knowledge of the surgical anatomical planes and the vascular anatomy of the colon.

Attrition reactor system

DOEpatents

Scott, C.D.; Davison, B.H.

1993-09-28

A reactor vessel for reacting a solid particulate with a liquid reactant has a centrifugal pump in circulatory flow communication with the reactor vessel for providing particulate attrition, resulting in additional fresh surface where the reaction can occur. 2 figures.

Line-of-sight deposition method

DOEpatents

Patten, J.W.; McClanahan, E.D.; Bayne, M.A.

1980-04-16

A line-of-sight method of depositing a film having substantially 100% of theoretical density on a substrate. A pressure vessel contains a target source having a surface thereof capable of emitting particles therefrom and a substrate with the source surface and the substrate surface positioned such that the source surface is substantially parallel to the direction of the particles impinging upon the substrate surface, the distance between the most remote portion of the substrate surface receiving the particles and the source surface emitting the particles in a direction parallel to the substrate surface being relatively small. The pressure in the vessel is maintained less than about 5 microns to prevent scattering and permit line-of-sight deposition. By this method the angles of incidence of the particles impinging upon the substrate surface are in the range of from about 45/sup 0/ to 90/sup 0/ even when the target surface area is greatly expanded to increase the deposition rate.

Line-of-sight deposition method

DOEpatents

Patten, James W.; McClanahan, Edwin D.; Bayne, Michael A.

1981-01-01

A line-of-sight method of depositing a film having substantially 100% of theoretical density on a substrate. A pressure vessel contains a target source having a surface thereof capable of emitting particles therefrom and a substrate with the source surface and the substrate surface positioned such that the source surface is substantially parallel to the direction of the particles impinging upon the substrate surface, the distance between the most remote portion of the substrate surface receiving the particles and the source surface emitting the particles in a direction parallel to the substrate surface being relatively small. The pressure in the vessel is maintained less than about 5 microns to prevent scattering and permit line-of-sight deposition. By this method the angles of incidence of the particles impinging upon the substrate surface are in the range of from about 45.degree. to 90.degree. even when the target surface area is greatly expanded to increase the deposition rate.

WTEC panel report on research submersibles and undersea technologies

NASA Technical Reports Server (NTRS)

Seymore, Richard J.; Blidberg, D. Richard; Brancart, Claude P.; Gentry, Larry L.; Kalvaitis, Algis N.; Lee, Michael J.; Mooney, Brad; Walsh, Don

1994-01-01

This report covers research submersibles and related subsea technologies in Finland, France, Russia, Ukraine and the United Kingdom. Manned, teleoperated, and autonomous submersibles were of interest. The panel found that, in contrast to the United States, Europe is making substantial progress in cooperative and coordinated research in subsea technology, including the development of standards. France is a leader in autonomous vehicle technology. Because much less was known a priori about the technologies in Russia and Ukraine, there were more new findings in those countries than in those Western European nations visited. However, Russia and Ukraine have a sizeable (and currently underutilized) infrastructure in this field, including a highly educated and experienced manpower pool, impressive (in some cases unique) facilities for physical testing, extensive fleets of seagoing research vessels capable of long voyages, and state-of-the-art facilities for conducting oceanographic investigations. The panel visited newly-formed commercial companies associated with long-standing submersible R&D and production centers in Russia and Ukraine. So far, these new efforts are undercapitalized, and as such represent opportunities at very low cost for Western nations, as detailed in the site reports.

WTEC panel report on research submersibles and undersea technologies

NASA Astrophysics Data System (ADS)

Seymore, Richard J.; Blidberg, D. Richard; Brancart, Claude P.; Gentry, Larry L.; Kalvaitis, Algis N.; Lee, Michael J.; Mooney, Brad; Walsh, Don

1994-06-01

This report covers research submersibles and related subsea technologies in Finland, France, Russia, Ukraine and the United Kingdom. Manned, teleoperated, and autonomous submersibles were of interest. The panel found that, in contrast to the United States, Europe is making substantial progress in cooperative and coordinated research in subsea technology, including the development of standards. France is a leader in autonomous vehicle technology. Because much less was known a priori about the technologies in Russia and Ukraine, there were more new findings in those countries than in those Western European nations visited. However, Russia and Ukraine have a sizeable (and currently underutilized) infrastructure in this field, including a highly educated and experienced manpower pool, impressive (in some cases unique) facilities for physical testing, extensive fleets of seagoing research vessels capable of long voyages, and state-of-the-art facilities for conducting oceanographic investigations. The panel visited newly-formed commercial companies associated with long-standing submersible R&D and production centers in Russia and Ukraine. So far, these new efforts are undercapitalized, and as such represent opportunities at very low cost for Western nations, as detailed in the site reports.

Cardiovascular dysfunction following spinal cord injury

PubMed Central

Partida, Elizabeth; Mironets, Eugene; Hou, Shaoping; Tom, Veronica J.

2016-01-01

Both sensorimotor and autonomic dysfunctions often occur after spinal cord injury (SCI). Particularly, a high thoracic or cervical SCI interrupts supraspinal vasomotor pathways and results in disordered hemodynamics due to deregulated sympathetic outflow. As a result of the reduced sympathetic activity, patients with SCI may experience hypotension, cardiac dysrhythmias, and hypothermia post-injury. In the chronic phase, changes within the CNS and blood vessels lead to orthostatic hypotension and life-threatening autonomic dysreflexia (AD). AD is characterized by an episodic, massive sympathetic discharge that causes severe hypertension associated with bradycardia. The syndrome is often triggered by unpleasant visceral or sensory stimuli below the injury level. Currently the only treatments are palliative – once a stimulus elicits AD, pharmacological vasodilators are administered to help reduce the spike in arterial blood pressure. However, a more effective means would be to mitigate AD development by attenuating contributing mechanisms, such as the reorganization of intraspinal circuits below the level of injury. A better understanding of the neuropathophysiology underlying cardiovascular dysfunction after SCI is essential to better develop novel therapeutic approaches to restore hemodynamic performance. PMID:27073353

Distribution of Different Sized Ocular Surface Vessels in Diabetics and Normal Individuals.

PubMed

Banaee, Touka; Pourreza, Hamidreza; Doosti, Hassan; Abrishami, Mojtaba; Ehsaei, Asieh; Basiry, Mohsen; Pourreza, Reza

2017-01-01

To compare the distribution of different sized vessels using digital photographs of the ocular surface of diabetic and normal individuals. In this cross-sectional study, red-free conjunctival photographs of diabetic and normal individuals, aged 30-60 years, were taken under defined conditions and analyzed using a Radon transform-based algorithm for vascular segmentation. The image areas occupied by vessels (AOV) of different diameters were calculated. The main outcome measure was the distribution curve of mean AOV of different sized vessels. Secondary outcome measures included total AOV and standard deviation (SD) of AOV of different sized vessels. Two hundred and sixty-eight diabetic patients and 297 normal (control) individuals were included, differing in age (45.50 ± 5.19 vs. 40.38 ± 6.19 years, P < 0.001), systolic (126.37 ± 20.25 vs. 119.21 ± 15.81 mmHg, P < 0.001) and diastolic (78.14 ± 14.21 vs. 67.54 ± 11.46 mmHg, P < 0.001) blood pressures. The distribution curves of mean AOV differed between patients and controls (smaller AOV for larger vessels in patients; P < 0.001) as well as between patients without retinopathy and those with non-proliferative diabetic retinopathy (NPDR); with larger AOV for smaller vessels in NPDR ( P < 0.001). Controlling for the effect of confounders, patients had a smaller total AOV, larger total SD of AOV, and a more skewed distribution curve of vessels compared to controls. Presence of diabetes mellitus is associated with contraction of larger vessels in the conjunctiva. Smaller vessels dilate with diabetic retinopathy. These findings may be useful in the photographic screening of diabetes mellitus and retinopathy.

Animating Autonomous Pedestrians

DTIC Science & Technology

2006-01-01

walkable surface in a region may be mapped onto a horizontal plane without loss of essential geometric information. Consequently, the 3D space may be...that the walkable surface in a region may be mapped onto a horizontal plane without loss of essential geometric information, such as the distance

Maiden Voyage of the Under-Ice Float

NASA Astrophysics Data System (ADS)

Shcherbina, A.; D'Asaro, E. A.; Light, B.; Deming, J. W.; Rehm, E.

2016-02-01

The Under-Ice Float (UIF) is a new autonomous platform for sea ice and upper ocean observations in the marginal ice zone (MIZ). UIF is based on the Mixed Layer Lagrangian Float design, inheriting its accurate buoyancy control and relatively heavy payload capability. A major challenge for sustained autonomous observations in the MIZ is detection of open water for navigation and telemetry surfacings. UIF employs the new surface classification algorithm based on the spectral analysis of surface roughness sensed by an upward-looking sonar. A prototype UIF was deployed in the MIZ of the central Arctic Ocean in late August 2015. The main payload of the first UIF was a bio-optical suit consisting of upward- and downward hyperspectral radiometers; temperature, salinity, chlorophyll, turbidity, and dissolved oxygen sensors, and a high-definition photo camera. In the early stages of its mission, the float successfully avoided ice, detected leads, surfaced in open water, and transmitted data and photographs. We will present the analysis of these observations from the full UIF mission extending into the freeze-up season.

46 CFR 28.540 - Free surface.

Code of Federal Regulations, 2010 CFR

2010-10-01

... liquid that is not a consumable or containing fish or a fish product that can shift as the vessel heels... transfer of liquids as the vessel heels are installed in the piping. (c) The moment of transference method...

46 CFR 28.540 - Free surface.

Code of Federal Regulations, 2011 CFR

2011-10-01

... liquid that is not a consumable or containing fish or a fish product that can shift as the vessel heels... transfer of liquids as the vessel heels are installed in the piping. (c) The moment of transference method...

Reactor pressure vessel head vents and methods of using the same

DOEpatents

Gels, John L; Keck, David J; Deaver, Gerald A

2014-10-28

Internal head vents are usable in nuclear reactors and include piping inside of the reactor pressure vessel with a vent in the reactor upper head. Piping extends downward from the upper head and passes outside of the reactor to permit the gas to escape or be forcibly vented outside of the reactor without external piping on the upper head. The piping may include upper and lowers section that removably mate where the upper head joins to the reactor pressure vessel. The removable mating may include a compressible bellows and corresponding funnel. The piping is fabricated of nuclear-reactor-safe materials, including carbon steel, stainless steel, and/or a Ni--Cr--Fe alloy. Methods install an internal head vent in a nuclear reactor by securing piping to an internal surface of an upper head of the nuclear reactor and/or securing piping to an internal surface of a reactor pressure vessel.

Comparison of in vivo and ex vivo imaging of the microvasculature with 2-photon fluorescence microscopy

NASA Astrophysics Data System (ADS)

Steinman, Joe; Koletar, Margaret; Stefanovic, Bojana; Sled, John G.

2016-03-01

This study evaluates 2-Photon fluorescence microscopy of in vivo and ex vivo cleared samples for visualizing cortical vasculature. Four mice brains were imaged with in vivo 2PFM. Mice were then perfused with a FITC gel and cleared in fructose. The same regions imaged in vivo were imaged ex vivo. Vessels were segmented automatically in both images using an in-house developed algorithm that accounts for the anisotropic and spatially varying PSF ex vivo. Through non-linear warping, the ex vivo image and tracing were aligned to the in vivo image. The corresponding vessels were identified through a local search algorithm. This enabled comparison of identical vessels in vivo/ex vivo. A similar process was conducted on the in vivo tracing to determine the percentage of vessels perfused. Of all the vessels identified over the four brains in vivo, 98% were present ex vivo. There was a trend towards reduced vessel diameter ex vivo by 12.7%, and the shrinkage varied between specimens (0% to 26%). Large diameter surface vessels, through a process termed 'shadowing', attenuated in vivo signal from deeper cortical vessels by 40% at 300 μm below the cortical surface, which does not occur ex vivo. In summary, though there is a mean diameter shrinkage ex vivo, ex vivo imaging has a reduced shadowing artifact. Additionally, since imaging depths are only limited by the working distance of the microscope objective, ex vivo imaging is more suitable for imaging large portions of the brain.

Surface layer and bloom dynamics observed with the Prince William Sound Autonomous Profiler

NASA Astrophysics Data System (ADS)

Campbell, R. W.

2016-02-01

As part of a recent long term monitoring effort, deployments of a WETLabs Autonomous Moored Profiler (AMP) began Prince William Sound (PWS) in 2013. The PWS AMP consists of a positively buoyant instrument frame, with a winch and associated electronics that profiles the frame from a park depth (usually 55 m) to the surface by releasing and retrieving a thin UHMWPE tether; it generally conducts a daily cast and measures temperature, salinity, chlorophyll-a fluorescence, turbidity, and oxygen and nitrate concentrations. Upward and downward looking ADCPs are mounted on a float below the profiler, and an in situ plankton imager is in development and will be installed in 2016. Autonomous profilers are a relatively new technology, and early deployments experienced a number of failures from which valuable lessons may be learned. Nevertheless, an unprecedented time series of the seasonal biogeochemical procession in the surface waters coastal Gulf of Alaska was collected in 2014 and 2015. The northern Gulf of Alaska has experienced a widespread warm anomaly since early 2014, and surface layer temperature anomalies in PWS were strongly positive during winter 2014. The spring bloom observed by the profiler began 2-3 weeks earlier than average, with surface nitrate depleted by late April. Although surface temperatures were still above average in 2015, bloom timing was much later, with a short vigorous bloom in late April and a subsurface bloom in late May that coincided with significant nitrate drawdown. As well as the vernal blooms, wind-driven upwelling events lead to several small productivity pulses that were evident in changes in nitrate and oxygen concentrations, and chlorophyll-a fluorescence. As well as providing a mechanistic understanding of surface layer biogeochemistry, high frequency observations such as these put historical observations in context, and provide new insights into the scales of variability in the annual cycles of the surface ocean in the North Pacific.

Biological implications of the hydrodynamics of swimming at or near the surface and in shallow water.

PubMed

Blake, R W

2009-03-01

The origins and effects of wave drag at and near the surface and in shallow water are discussed in terms of the dispersive waves generated by streamlined technical bodies of revolution and by semi-aquatic and aquatic animals with a view to bearing on issues regarding the design and function of autonomous surface and underwater vehicles. A simple two-dimensional model based on energy flux, allowing assessment of drag and its associated wave amplitude, is applied to surface swimming in Lesser Scaup ducks and is in good agreement with measured values. It is argued that hydrodynamic limitations to swimming at speeds associated with the critical Froude number ( approximately 0.5) and hull speed do not necessarily set biological limitations as most behaviours occur well below the hull speed. From a comparative standpoint, the need for studies on the hull displacement of different forms is emphasized. For forms in surface proximity, drag is a function of both Froude and Reynolds numbers. Whilst the depth dependence of wave drag is not particularly sensitive to Reynolds number, its magnitude is, with smaller and slower forms subject to relatively less drag augmentation than larger, faster forms that generate additional resistance due to ventilation and spray. A quasi-steady approach to the hydrodynamics of swimming in shallow water identifies substantial drag increases relative to the deeply submerged case at Froude numbers of about 0.9 that could limit the performance of semi-aquatic and aquatic animals and autonomous vehicles. A comparative assessment of fast-starting trout and upside down catfish shows that the energy losses of fast-starting fish are likely to be less for fish in surface proximity in deep water than for those in shallow water. Further work on unsteady swimming in both circumstances is encouraged. Finally, perspectives are offered as to how autonomous surface and underwater vehicles in surface proximity and shallow water could function to avoid prohibitive hydrodynamic resistance, thereby increasing their operational life.

Beam limiter for thermonuclear fusion devices

DOEpatents

Kaminsky, Manfred S.

1976-01-01

A beam limiter circumscribes the interior surface of a vacuum vessel to inhibit collisions of contained plasma and the vessel walls. The cross section of the material making up the limiter has a flatsided or slightly concave portion of increased width towards the plasma and portions of decreased width towards the interior surface of the vessel. This configuration is designed to prevent a major fraction of the material sputtered, vaporized and blistered from the limiter from reaching the plasma. It also allows adequate heat transfer from the wider to the narrower portions. The preferred materials for the beam limiter are solids of sintered, particulate materials of low atomic number with low vapor pressure and low sputtering and blistering yields.

On the autonomous motion of active drops or bubbles.

PubMed

Ryazantsev, Yuri S; Velarde, Manuel G; Guzman, Eduardo; Rubio, Ramón G; Ortega, Francisco; Montoya, Juan-Jose

2018-05-19

Thermo-capillary stresses on the surface of a drop can be the result of a non-isothermal surface chemical conversion of a reactant dissolved in the host fluid. The strength of heat production (with e.g. absorption) on the surface is ruled by the diffusion of the reactant and depends on the state of motion of the drop. Such thermo-capillary stresses can provoke the motion of the drop or its motionless state in the presence of an external body force. If in the balance of forces, including indeed viscous drag, the net resultant force vanishes there is the possibility of autonomous motion with constant velocity of the drop. Focusing on drops with radii in the millimeter range provided here is a quantitative study of the possibility of such autonomous motion when the drop, considered as active unit, is seat of endo- or exo-thermic reactive processes that dominate its motion. The framework is restricted to Stokes flows in the hydrodynamics, negligible heat Peclet number while the solute Peclet number is considered very high. A boundary layer approximation is used in the description of reactant diffusion. Those processes eventually end up in the action being expressed by surface tension gradients and the Marangoni effect. Explicit expressions of the force acting on the drop and the velocity fields inside and outside the drop are provided. Some significant particular cases are discussed to illustrate the usefulness of the theory. Copyright © 2018. Published by Elsevier Inc.

33 CFR 165.1151 - Security Zones; liquefied hazardous gas tank vessels, San Pedro Bay, California.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the sea floor, within a 500 yard radius around any liquefied hazardous gas (LHG) tank vessel that is... waters, extending from the surface to the sea floor, within a 500 yard radius around any LHG tank vessel that is moored, or in the process of mooring, at any berth within the Los Angeles or Long Beach port...

33 CFR 165.1151 - Security Zones; liquefied hazardous gas tank vessels, San Pedro Bay, California.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the sea floor, within a 500 yard radius around any liquefied hazardous gas (LHG) tank vessel that is... waters, extending from the surface to the sea floor, within a 500 yard radius around any LHG tank vessel that is moored, or in the process of mooring, at any berth within the Los Angeles or Long Beach port...

33 CFR 165.1151 - Security Zones; liquefied hazardous gas tank vessels, San Pedro Bay, California.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the sea floor, within a 500 yard radius around any liquefied hazardous gas (LHG) tank vessel that is... waters, extending from the surface to the sea floor, within a 500 yard radius around any LHG tank vessel that is moored, or in the process of mooring, at any berth within the Los Angeles or Long Beach port...

33 CFR 165.1151 - Security Zones; liquefied hazardous gas tank vessels, San Pedro Bay, California.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the sea floor, within a 500 yard radius around any liquefied hazardous gas (LHG) tank vessel that is... waters, extending from the surface to the sea floor, within a 500 yard radius around any LHG tank vessel that is moored, or in the process of mooring, at any berth within the Los Angeles or Long Beach port...

Precise laser gyroscope for autonomous inertial navigation

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

Kuznetsov, A G; Molchanov, A V; Izmailov, E A

2015-01-31

Requirements to gyroscopes of strapdown inertial navigation systems for aircraft application are formulated. The construction of a ring helium – neon laser designed for autonomous navigation is described. The processes that determine the laser service life and the relation between the random error of the angular velocity measurement and the surface relief features of the cavity mirrors are analysed. The results of modelling one of the promising approaches to processing the laser gyroscope signals are presented. (laser gyroscopes)

Powered Descent Trajectory Guidance and Some Considerations for Human Lunar Landing

NASA Technical Reports Server (NTRS)

Sostaric, Ronald R.

2007-01-01

The Autonomous Precision Landing and Hazard Detection and Avoidance Technology development (ALHAT) will enable an accurate (better than 100m) landing on the lunar surface. This technology will also permit autonomous (independent from ground) avoidance of hazards detected in real time. A preliminary trajectory guidance algorithm capable of supporting these tasks has been developed and demonstrated in simulations. Early results suggest that with expected improvements in sensor technology and lunar mapping, mission objectives are achievable.

Design and Hardware-in-the-Loop Implementation of Optimal Canonical Maneuvers for an Autonomous Planetary Aerial Vehicle

DTIC Science & Technology

2012-12-01

selflessly working your own school and writing schedule around mine , supporting me throughout career paths that have been anything but traditional...observation, and other scientific research and exploration purposes. 4 A ground rover on a planet, moon, or other body such as an asteroid must...applied to autonomous craft that could eventually operate on the surface of planets, moons, and asteroids , as well as in Earth orbit or deep space

Calculation and benchmarking of an azimuthal pressure vessel neutron fluence distribution using the BOXER code and scraping experiments

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

Holzgrewe, F.; Hegedues, F.; Paratte, J.M.

1995-03-01

The light water reactor BOXER code was used to determine the fast azimuthal neutron fluence distribution at the inner surface of the reactor pressure vessel after the tenth cycle of a pressurized water reactor (PWR). Using a cross-section library in 45 groups, fixed-source calculations in transport theory and x-y geometry were carried out to determine the fast azimuthal neutron flux distribution at the inner surface of the pressure vessel for four different cycles. From these results, the fast azimuthal neutron fluence after the tenth cycle was estimated and compared with the results obtained from scraping test experiments. In these experiments,more » small samples of material were taken from the inner surface of the pressure vessel. The fast neutron fluence was then determined form the measured activity of the samples. Comparing the BOXER and scraping test results have maximal differences of 15%, which is very good, considering the factor of 10{sup 3} neutron attenuation between the reactor core and the pressure vessel. To compare the BOXER results with an independent code, the 21st cycle of the PWR was also calculated with the TWODANT two-dimensional transport code, using the same group structure and cross-section library. Deviations in the fast azimuthal flux distribution were found to be <3%, which verifies the accuracy of the BOXER results.« less

[Intraosseous veins of the maxilla in the newborn].

PubMed

Bogdanov, R A

1975-12-01

The intraosseous veins of the maxilla in newborns grow larger with enlargement of the bone and become disposed in three mutually perpendicular planes. The venous plexus of the alveolar process is large. V. v. vallares are thin and interlace forming a network. The veins of interdental septum are well pronounced. The thick venous network of the periosteum and the mucous membrane of the nasal surface of the palatine process includes the vessels transversal and longitudinal to the nasal septum. The venous loops of the incisor part are of triangular, pentagonal and polygonal shape. The veins of the palatine process are connected with 3-4 large vessels falling into the vessels of the tear duct. The transversal and oblique veins of the oral surface of the palatine process are connected with large vessels disposed in parallel to the medial structure of the hard palate. The venous network of the incisor part of the bone is restricted by densified small arc-shaped plexuses. Two-three largest veins lie sagittally and, connected by arc-shaped anastomoses, are tributaries of the vessels of the palate bone, soft palate and pharynx.

Effect of surface modification of fibers with a polymer coating on the interlaminar shear strength of a composite and the translation of fiber strength in an F-12 aramid/epoxy composite vessel

NASA Astrophysics Data System (ADS)

Shu-hui, Zhang; Guo-zheng, Liang; Wei, Zhang; Jin-fang, Zeng

2006-11-01

The surface of aramid fibers was modified with a polymer coating — a surface treatment reagent containing epoxy resin. The resulting fibers were examined by using NOL tests, hydroburst tests, and the scanning electron microscopy. The modified fibers had a rougher surface than the untreated ones. The interlaminar shear strength of an aramid-fiber-reinforced epoxy composite was highest when the concentration of polymer coating system was 5%. The translation of fiber strength in an aramid/epoxy composite vessel was improved by 8%. The mechanism of the surface treatment of fibers in improving the mechanical properties of aramid/epoxy composites is discussed.

Salinity Processes in the Upper Ocean Regional Study (SPURS)

NASA Image and Video Library

2012-09-04

Woods Hole Oceanographic Institution Scientist Dave Fratantoni works on the EcoMapper AUVs (autonomous underwater vehicles) onboard the Institute's research vessel Knorr, Tuesday, Sept. 4, 2012, in Woods Hole, Mass. The EcoMappers will be deployed in the Atlantic Ocean as part of the Salinity Processes in the Upper Ocean Regional Study (SPURS) which is set to sail on Sept. 6. The NASA-sponsored expedition will sail to the North Atlantic's saltiest spot to get a detailed, 3-D picture of how salt content fluctuates in the ocean's upper layers and how these variations are related to shifts in rainfall patterns around the planet. Photo Credit: (NASA/Bill Ingalls)

Salinity Processes in the Upper Ocean Regional Study (SPURS)

NASA Image and Video Library

2012-09-04

Two EcoMapper AUVs (autonomous underwater vehicles) are seen onboard the the Woods Hole Oceanographic Institution research vessel Knorr on Tuesday, Sept. 4, 2012, in Woods Hole, Mass. The EcoMappers will be deployed in the Atlantic Ocean as part of the Salinity Processes in the Upper Ocean Regional Study (SPURS) which is set to sail on Sept. 6. The NASA-sponsored expedition will sail to the North Atlantic's saltiest spot to get a detailed, 3-D picture of how salt content fluctuates in the ocean's upper layers and how these variations are related to shifts in rainfall patterns around the planet. Photo Credit: (NASA/Bill Ingalls)

Self-sustained peristaltic waves: Explicit asymptotic solutions

NASA Astrophysics Data System (ADS)

Dudchenko, O. A.; Guria, G. Th.

2012-02-01

A simple nonlinear model for the coupled problem of fluid flow and contractile wall deformation is proposed to describe peristalsis. In the context of the model the ability of a transporting system to perform autonomous peristaltic pumping is interpreted as the ability to propagate sustained waves of wall deformation. Piecewise-linear approximations of nonlinear functions are used to analytically demonstrate the existence of traveling-wave solutions. Explicit formulas are derived which relate the speed of self-sustained peristaltic waves to the rheological properties of the transporting vessel and the transported fluid. The results may contribute to the development of diagnostic and therapeutic procedures for cases of peristaltic motility disorders.

The Subpolar North Atlantic Spring Bloom - What Did We Learn from the NAB 2008 Autonomous Experiment?

NASA Astrophysics Data System (ADS)

Perry, M. J.

2015-12-01

The subpolar North Atlantic bloom is one of the most remarkable features on the planet, with almost explosive 'greening' of the oceans. Over decades, investigators from countries bordering the North Atlantic have caught snippets of the bloom from research vessels or merchant ships transiting between continents. On 4 April 2008, Eric D'Asaro, Craig Lee, and I began a comprehensive study of the initiation and demise of the spring bloom using 2 types of autonomous platforms - a patch-following Lagrangian mixed-layer float and 4 float-following gliders. The 3 mo autonomous experiment integrated measurements from the float, gliders and ships, observations from satellites, and analyses from models. The diatom-dominated bloom began in mid April when the water column stabilized, not by solar warming, but rather by eddy-driven slumping of horizontal density gradients. The resulting bloom was patchy in both biomass and phytoplankton diversity, despite high, non-limiting concentrations of macronutrients. Magnitudes and relative proportions of net community productivity (NCP; determined from autonomous budgets of O2 and NO3) and net phytoplankton productivity (NPP; computed from ship-based photosynthetic parameters and float-based biomass and light) diverged as the bloom evolved, with higher fractions of particulate organic carbon (POC) consumed within the mixed layer as the bloom aged. Export productivity (EP; derived as the difference between NCP and accumulation rate of POC) was of similar magnitude during the May diatom bloom and the June picophytoplankton bloom. When silicic acid dropped to 1 μM, diatoms aggregated and sank; the deep flux event was dominated by resting spores of Chaetoceros. Although a short-lived event, it was ubiquitously observed by the 4 gliders and ship. An eddy-driven subduction event was likewise observed, indicating transport of otherwise non-sinking POC along isopycnals to depths of > 200 m. These striking export events reinforce the value of a persistent, distributed presence afforded by a network of autonomous platforms to catch and follow key, transient events. NAB 2008 demonstrated the power of autonomous platforms to decipher productivities and carbon fluxes at the patch scale, but left the enticing challenge of how to scale from the patch to the basin for another time.

Image Dependent Relative Formation Navigation for Autonomous Aerial Refueling

DTIC Science & Technology

2011-03-01

and local variations of the Earth’s surface make a mathematical model difficult to create and use. The definition of an equipotential surface ...controlled with flight control surfaces attached to it. To refuel using this method, the receiver pilot flies the aircraft to within a defined refueling...I-frame would unnecessarily complicate aircraft navigation that, by definition, is limited to altitudes relatively close to the surface of the Earth

Pressure vessel bottle mount

NASA Technical Reports Server (NTRS)

Wingett, Paul (Inventor)

2001-01-01

A mounting assembly for mounting a composite pressure vessel to a vehicle includes a saddle having a curved surface extending between two pillars for receiving the vessel. The saddle also has flanged portions which can be bolted to the vehicle. Each of the pillars has hole in which is mounted the shaft portion of an attachment member. A resilient member is disposed between each of the shaft portions and the holes and loaded by a tightening nut. External to the holes, each of the attachment members has a head portion to which a steel band is attached. The steel band circumscribes the vessel and translates the load on the springs into a clamping force on the vessel. As the vessel expands and contracts, the resilient members expand and contract so that the clamping force applied by the band to the vessel remains constant.

46 CFR 78.17-20 - Drafts and load line markings.

Code of Federal Regulations, 2010 CFR

2010-10-01

... surface of the water in which the vessel is floating. (2) When an allowance for draft is made for density of the water in which the vessel is floating, this density is to be noted in the official logbook. ...

Planetary Rover Robotics Experiments in Education: HUSAR-5, the NXT-Based Rover Model for Measuring the Planetary Surface

NASA Astrophysics Data System (ADS)

Lang, Á.; Bérczi, Sz.; Szalay, K.; Prajczer, P.; Kocsis, Á.

2014-11-01

We report about the work of the HUSAR-5 groups from the Széchenyi István Gimnázium High School Sopron, Hungary. We build and program robot-rovers, that can autonomous move and measure on a planetary surface.

NASA Dryden Status: Aerospace Control and Guidance Sub-Committee Meeting 109

NASA Technical Reports Server (NTRS)

Jacobson, Steven R.

2012-01-01

NASA Dryden has been engaging in some exciting work that will enable lighter weight and more fuel efficient vehicles through advanced control and dynamics technologies. The main areas of emphasis are Enabling Light-weight Flexible Structures, real time control surface optimization for fuel efficiency and autonomous formation flight. This presentation provides a description of the current and upcoming work in these areas. Additionally, status is for the Dreamchaser pilot training activity and KQ-X autonomous aerial refueling.

Autonomous search and surveillance with small fixed wing aircraft

NASA Astrophysics Data System (ADS)

McGee, Timothy Garland

Small unmanned aerial vehicles (UAVs) have the potential to act as low cost tools in a variety of both civilian and military applications including traffic monitoring, border patrol, and search and rescue. While most current operational UAV systems require human operators, advances in autonomy will allow these systems to reach their full potential as sensor platforms. This dissertation specifically focuses on developing advanced control, path planning, search, and image processing techniques that allow small fixed wing aircraft to autonomously collect data. The problems explored were motivated by experience with the development and experimental flight testing of a fleet of small autonomous fixed wing aircraft. These issues, which have not been fully addressed in past work done on ground vehicles or autonomous helicopters, include the influence of wind and turning rate constraints, the non-negligible velocity of ground targets relative to the aircraft velocity, and limitations on sensor size and processing power on small vehicles. Several contributions for the autonomous operation of small fixed wing aircraft are presented. Several sliding surface controllers are designed which extend previous techniques to include variable sliding surface coefficients and the use of spatial vehicle dynamics. These advances eliminate potential singularities in the control laws to follow spatially defined paths and allow smooth transition between controllers. The optimal solution for the problem of path planning through an ordered set of points for an aircraft with a bounded turning rate in the presence of a constant wind is then discussed. Path planning strategies are also explored to guarantee that a searcher will travel within sensing distance of a mobile ground target. This work assumes only a maximum velocity of the target and is designed to succeed for any possible path of the target. Closed-loop approximations of both the path planning and search techniques, using the sliding surface controllers already discussed, are also studied. Finally, a novel method is presented to detect obstacles by segmenting an image into sky and non-sky regions. The feasibility of this method is demonstrated experimentally on an aircraft test bed.

Proof test criteria for thin-walled 2219 aluminum pressure vessels. Volume 1: Program summary and data analysis

NASA Technical Reports Server (NTRS)

Finger, R. W.

1976-01-01

This experimental program was undertaken to investigate the crack growth behavior of deep surface flaws in 2219 aluminum. The program included tests of uniaxially loaded surface flaw and center crack panels at temperatures ranging from 20K (-423 F) to ambient. The tests were conducted on both the base metal and as-welded weld metal material. The program was designed to provide data on the mechanisms of failure by ligament penetration, and the residual cyclic life, after proof-testing, of a vessel which has been subjected to incipient penetration by the proof test. The results were compared and analyzed with previously developed data to develop guidelines for the proof testing of thin walled 2219 pressure vessels.

Using Seasonal Forecasting Data for Vessel Routing

NASA Astrophysics Data System (ADS)

Bell, Ray; Kirtman, Ben

2017-04-01

We present an assessment of seasonal forecasting of surface wind speed, significant wave height and ocean surface current speed in the North Pacific for potential use of vessel routing from Singapore to San Diego. WaveWatchIII is forced with surface winds and ocean surface currents from the Community Climate System Model 4 (CCSM4) retrospective forecasts for the period of 1982-2015. Several lead time forecasts are used from zero months to six months resulting in 2,720 model years, ensuring the findings from this study are robust. July surface wind speed and significant wave height can be skillfully forecast with a one month lead time, with the western North Pacific being the most predictable region. Beyond May initial conditions (lead time of two months) the El Niño Southern Oscillation (ENSO) Spring predictability barrier limits skill of significant wave height but there is skill for surface wind speed with January initial conditions (lead time of six months). In a separate study of vessel routing between Norfolk, Virginia and Gibraltar we demonstrate the benefit of a multimodel approach using the North American Multimodel Ensemble (NMME). In collaboration with Charles River Analytics an all-encompassing forecast is presented by using machine learning on the various ensembles which can be using used for industry applications.

Vessel structural support system

DOEpatents

Jenko, James X.; Ott, Howard L.; Wilson, Robert M.; Wepfer, Robert M.

1992-01-01

Vessel structural support system for laterally and vertically supporting a vessel, such as a nuclear steam generator having an exterior bottom surface and a side surface thereon. The system includes a bracket connected to the bottom surface. A support column is pivotally connected to the bracket for vertically supporting the steam generator. The system also includes a base pad assembly connected pivotally to the support column for supporting the support column and the steam generator. The base pad assembly, which is capable of being brought to a level position by turning leveling nuts, is anchored to a floor. The system further includes a male key member attached to the side surface of the steam generator and a female stop member attached to an adjacent wall. The male key member and the female stop member coact to laterally support the steam generator. Moreover, the system includes a snubber assembly connected to the side surface of the steam generator and also attached to the adjacent wall for dampening lateral movement of the steam generator. In addition, the system includes a restraining member of "flat" attached to the side surface of the steam generator and a bumper attached to the adjacent wall. The flat and the bumper coact to further laterally support the steam generator.

33 CFR 165.836 - Security Zone; Escorted Vessels, Mobile, Alabama, Captain of the Port.

Code of Federal Regulations, 2011 CFR

2011-07-01

... lights, vessel markings, or with agency insignia as follows: Coast Guard surface or air asset displaying... coming up onto or coming off a plane; or (3) Creating an excessive wake or surge. (b) Regulated area. All...

Exploiting Electric and Magnetic Fields for Underwater Characterization

DTIC Science & Technology

2011-03-01

geophysical surveys are primarily limited to passive magnetic systems towed from a surface vessel. These systems utilize fluxgate , Overhauser, or atomic... magnetometer sensors, often deployed in arrays towed from the stern of small to moderate-size vessels. Active source electromagnetic methods have been

Control of AUVs using differential flatness theory and the derivative-free nonlinear Kalman Filter

NASA Astrophysics Data System (ADS)

Rigatos, Gerasimos; Raffo, Guilerme

2015-12-01

The paper proposes nonlinear control and filtering for Autonomous Underwater Vessels (AUVs) based on differential flatness theory and on the use of the Derivative-free nonlinear Kalman Filter. First, it is shown that the 6-DOF dynamic model of the AUV is a differentially flat one. This enables its transformation into the linear canonical (Brunovsky) form and facilitates the design of a state feedback controller. A problem that has to be dealt with is the uncertainty about the parameters of the AUV's dynamic model, as well the external perturbations which affect its motion. To cope with this, it is proposed to use a disturbance observer which is based on the Derivative-free nonlinear Kalman Filter. The considered filtering method consists of the standard Kalman Filter recursion applied on the linearized model of the vessel and of an inverse transformation based on differential flatness theory, which enables to obtain estimates of the state variables of the initial nonlinear model of the vessel. The Kalman Filter-based disturbance observer performs simultaneous estimation of the non-measurable state variables of the AUV and of the perturbation terms that affect its dynamics. By estimating such disturbances, their compensation is also succeeded through suitable modification of the feedback control input. The efficiency of the proposed AUV control and estimation scheme is confirmed through simulation experiments.

Copper-assisted, anti-reflection etching of silicon surfaces

DOEpatents

Toor, Fatima; Branz, Howard

2014-08-26

A method (300) for etching a silicon surface (116) to reduce reflectivity. The method (300) includes electroless deposition of copper nanoparticles about 20 nanometers in size on the silicon surface (116), with a particle-to-particle spacing of 3 to 8 nanometers. The method (300) includes positioning (310) the substrate (112) with a silicon surface (116) into a vessel (122). The vessel (122) is filled (340) with a volume of an etching solution (124) so as to cover the silicon surface (116). The etching solution (124) includes an oxidant-etchant solution (146), e.g., an aqueous solution of hydrofluoric acid and hydrogen peroxide. The silicon surface (116) is etched (350) by agitating the etching solution (124) with, for example, ultrasonic agitation, and the etching may include heating (360) the etching solution (124) and directing light (365) onto the silicon surface (116). During the etching, copper nanoparticles enhance or drive the etching process.

A Miniaturized 0.78-mW/cm2 Autonomous Thermoelectric Energy-Harvesting Platform for Biomedical Sensors.

PubMed

Rozgic, Dejan; Markovic, Dejan

2017-08-01

In order to use thermoelectric energy harvesters (TEHs) as a truly autonomous energy source for size-limited sensing applications, it is essential to improve the power conversion efficiency and energy density. This study presents a thin-film, array-based TEH with a surface area of 0.83 cm 2 . The TEH autonomously supplies a power management IC fabricated in a 65-nm CMOS technology. The IC utilizes a single-inductor topology with integrated analog maximum power point tracking (MPPT), resulting in a 68% peak end-to-end efficiency (92% converter efficiency) and less than 20-ms MPPT. In an in-vivo test, a 645-μW regulated output power (effective 3.5 K of temperature gradient) was harvested from a rat implanted with our TEH, demonstrating true energy independence in a real environment while showing a 7.9 × improvement in regulated power density compared to the state-of-the-art. The system showed autonomous operation down to 65-mV TEH input.

Control technique for planetary rover

NASA Technical Reports Server (NTRS)

Nakatani, Ichiro; Kubota, Takashi; Adachi, Tadashi; Saitou, Hiroaki; Okamoto, Sinya

1994-01-01

Beginning next century, several schemes for sending a planetary rover to the moon or Mars are being planned. As part of the development program, autonomous navigation technology is being studied to allow the rover the ability to move autonomously over a long range of unknown planetary surface. In the previous study, we ran the autonomous navigation experiment on an outdoor test terrain by using a rover test-bed that was controlled by a conventional sense-plan-act method. In some cases during the experiment, a problem occurred with the rover moving into untraversable areas. To improve this situation, a new control technique has been developed that gives the rover the ability of reacting to the outputs of the proximity sensors, a reaction behavior if you will. We have developed a new rover test-bed system on which an autonomous navigation experiment was performed using the newly developed control technique. In this outdoor experiment, the new control technique effectively produced the control command for the rover to avoid obstacles and be guided to the goal point safely.

Reconstruction of Thermographic Signals to Map Perforator Vessels in Humans

PubMed Central

Liu, Wei-Min; Maivelett, Jordan; Kato, Gregory J.; Taylor, James G.; Yang, Wen-Chin; Liu, Yun-Chung; Yang, You-Gang; Gorbach, Alexander M.

2013-01-01

Thermal representations on the surface of a human forearm of underlying perforator vessels have previously been mapped via recovery-enhanced infrared imaging, which is performed as skin blood flow recovers to baseline levels following cooling of the forearm. We noted that the same vessels could also be observed during reactive hyperaemia tests after complete 5-min occlusion of the forearm by an inflatable cuff. However, not all subjects showed vessels with acceptable contrast. Therefore, we applied a thermographic signal reconstruction algorithm to reactive hyperaemia testing, which substantially enhanced signal-to-noise ratios between perforator vessels and their surroundings, thereby enabling their mapping with higher accuracy and a shorter occlusion period. PMID:23667389

Pressure-actuated joint system

NASA Technical Reports Server (NTRS)

McGuire, John R. (Inventor)

2004-01-01

A pressure vessel is provided that includes first and second case segments mated with one another. First and second annular rubber layers are disposed inboard of the first and second case segments, respectively. The second annular rubber layer has a slot extending from the radial inner surface across a portion of its thickness to define a main body portion and a flexible portion. The flexible portion has an interfacing surface portion abutting against an interfacing surface portion of the first annular rubber layer to follow movement of the first annular rubber layer during operation of the pressure vessel. The slot receives pressurized gas and establishes a pressure-actuated joint between the interfacing surface portions. At least one of the interfacing surface portions has a plurality of enclosed and sealed recesses formed therein.

Ultrasonic material hardness depth measurement

DOEpatents

Good, M.S.; Schuster, G.J.; Skorpik, J.R.

1997-07-08

The invention is an ultrasonic surface hardness depth measurement apparatus and method permitting rapid determination of hardness depth of shafts, rods, tubes and other cylindrical parts. The apparatus of the invention has a part handler, sensor, ultrasonic electronics component, computer, computer instruction sets, and may include a display screen. The part handler has a vessel filled with a couplant, and a part rotator for rotating a cylindrical metal part with respect to the sensor. The part handler further has a surface follower upon which the sensor is mounted, thereby maintaining a constant distance between the sensor and the exterior surface of the cylindrical metal part. The sensor is mounted so that a front surface of the sensor is within the vessel with couplant between the front surface of the sensor and the part. 12 figs.

General and crevice corrosion study of the in-wall shielding materials for ITER vacuum vessel

NASA Astrophysics Data System (ADS)

Joshi, K. S.; Pathak, H. A.; Dayal, R. K.; Bafna, V. K.; Kimihiro, Ioki; Barabash, V.

2012-11-01

Vacuum vessel In-Wall Shield (IWS) will be inserted between the inner and outer shells of the ITER vacuum vessel. The behaviour of IWS in the vacuum vessel especially concerning the susceptibility to crevice of shielding block assemblies could cause rapid and extensive corrosion attacks. Even galvanic corrosion may be due to different metals in same electrolyte. IWS blocks are not accessible until life of the machine after closing of vacuum vessel. Hence, it is necessary to study the susceptibility of IWS materials to general corrosion and crevice corrosion under operations of ITER vacuum vessel. Corrosion properties of IWS materials were studied by using (i) Immersion technique and (ii) Electro-chemical Polarization techniques. All the sample materials were subjected to a series of examinations before and after immersion test, like Loss/Gain weight measurement, SEM analysis, and Optical stereo microscopy, measurement of surface profile and hardness of materials. After immersion test, SS 304B4 and SS 304B7 showed slight weight gain which indicate oxide layer formation on the surface of coupons. The SS 430 material showed negligible weight loss which indicates mild general corrosion effect. On visual observation with SEM and Metallography, all material showed pitting corrosion attack. All sample materials were subjected to series of measurements like Open Circuit potential, Cyclic polarization, Pitting potential, protection potential, Critical anodic current and SEM examination. All materials show pitting loop in OC2 operating condition. However, its absence in OC1 operating condition clearly indicates the activity of chloride ion to penetrate oxide layer on the sample surface, at higher temperature. The critical pitting temperature of all samples remains between 100° and 200°C.

Simply actuated closure for a pressure vessel - Design for use to trap deep-sea animals

NASA Technical Reports Server (NTRS)

Yayanos, A. A.

1977-01-01

A pressure vessel is described that can be closed by a single translational motion within 1 sec. The vessel is a key component of a trap for small marine animals and operates automatically on the sea floor. As the vessel descends to the sea floor, it is subjected both internally and externally to the high pressures of the deep sea. The mechanism for closing the pressure vessel on the sea floor is activated by the timed release of the ballast which was used to sink the trap. As it rises to the sea surface, the internal pressure of the vessel remains near the value present on the sea floor. The pressure vessel has been used in simulated ocean deployments and in the deep ocean (9500 m) with a 75%-85% retention of the deep-sea pressure. Nearly 100% retention of pressure can be achieved by using an accumulator filled with a gas.

From Deck Hand to Program Manager - 30 years with Research Vessels

NASA Astrophysics Data System (ADS)

Prince, J. M.

2012-12-01

Starting in 1980 as a Mate and Deck Hand and working my way up to Captain, Marine Superintendent, UNOLS Executive Secretary and now as an ONR Research Facilities Program Manager focused on the acquisition of two new Ocean Class Research Vessels, I have witnessed first hand the evolution of the U.S. Academic Research Fleet. The author will focus on a few key events in the evolution of the modern research fleet. As a deck hand, mate and Captain, I was involved in an early multi-disciplinary effort often using two ships working together to conduct sampling and analysis in Physical, Chemical and Biological oceanography. The VERTEX cruises led by John Martin and others used the R/V CAYUSE and R/V WECOMA extensively through out the NE Pacific Ocean conducting research that led to Dr. Martin's Iron Hypothesis. This work and that of others involving trace metal clean sampling and clean laboratories on board our ships pushed many new and demanding requirements for future vessels. As a ship scheduler and as chair of the Research Vessel Operators Committee (RVOC) I saw the increasing use of Remotely Operated Vehicles to complement the work being done with the ALVIN and other occupied submersibles. This led to scheduling challenges and changes to our safety standards, but also to many new opportunities for discoveries on the many mid-ocean ridges and hydro-thermal vent fields. More recently, Autonomous Underwater Vehicles (AUV) and Unmanned Aerial Vehicles (UAV) and aircraft have been used simultaneously with research vessels such as during a multi-PI, multi-ship program in the Monterey Bay. Communications at sea have changed dramatically in the past thirty years. No longer are we limited to reading the data from a spreadsheet over a Single Side Band radio so that the PI ashore can track the progress of a cruise and provide guidance for the next day's sampling. Full bandwidth communications are becoming the norm with the capability of streaming video from an ROV to shore or to exchange data for real-time modeling updates. These new technologies and the multi-disciplinary nature of ocean science research projects have led to many improvements to our Science Mission Requirements for new research vessels. In the next three to four years, three new research vessels will come on line followed by the possibility of three additional Regional Class research vessels. All of these new vessels will come with improved capabilities to support research projects of the future.

Smart Composite Overwrapped Pressure Vessel - Integrated Structural Health Monitoring System to Meet Space Exploration and International Space Station Mission Assurance Needs

NASA Technical Reports Server (NTRS)

Saulsberry, Regor; Nichols, Charles; Waller, Jess

2012-01-01

Currently there are no integrated NDE methods for baselining and monitoring defect levels in fleet for Composite Overwrapped Pressure Vessels (COPVs) or related fracture critical composites, or for performing life-cycle maintenance inspections either in a traditional remove-and-inspect mode or in a more modern in situ inspection structural health monitoring (SHM) mode. Implicit in SHM and autonomous inspection is the existence of quantitative accept-reject criteria. To be effective, these criteria must correlate with levels of damage known to cause composite failure. Furthermore, implicit in SHM is the existence of effective remote sensing hardware and automated techniques and algorithms for interpretation of SHM data. SHM of facture critical composite structures, especially high pressure COPVs, is critical to the success of nearly every future NASA space exploration program as well as life extension of the International Space Station. It has been clearly stated that future NASA missions may not be successful without SHM [1]. Otherwise, crews will be busy addressing subsystem health issues and not focusing on the real NASA mission

Spontaneous subserosal venous rupture overlying a uterine leiomyoma in a young woman.

PubMed

Jenayah, Amel Achour; Saoudi, Sarah; Sferi, Nour; Skander, Rim; Marzouk, Sofiène Ben; Cherni, Abdallah; Sfar, Ezzeddine; Chelli, Dalenda; Boudaya, Fethia

2017-01-01

Uterine leiomyomas are very common tumors found in women. Rupture of veins on the surface of uterine leiomyoma is an unusual source of hemoperitoneum. It is an extremely uncommon gynaecological cause of hemoperitoneum. It is a life threatening emergency. We report a case of massive intraperitoneal hemorrhage due to rupture of vessels on the surface of subserous leiomyoma. A differential diagnosis of rupture of leiomyoma'ssurface vessel should be considered, while dealing with a case of hemoperitoneum with pelvic mass.

Cooperative Control of Unmanned Surface Vessels and Unmanned Underwater Vessels for Asset Protection

DTIC Science & Technology

2015-05-18

are met as well. APPENDIX A –CODE FOR SIMPLE SURFACE PRIMARY SIMULATION % Input Variables cap desired 0.95; xd 2000; yd 2000...50 for t 1:1:50 % Capability Calculations if ((640/(2*sqrt((yd y1)^2 + ( xd x1)^2)*tand(24/2))) > 3) & ((640/(2*sqrt((yd...y2)^2 + ( xd x2)^2)*tand(24/2))) > 3) c1 1 0.0000000000000001*sqrt((yd y1)^2 + ( xd x1)^2); c2 (1 0.0000000000000001

Streamlined vessels for speedboats: Macro modifications of shark skin design applications

NASA Astrophysics Data System (ADS)

Ibrahim, M. D.; Amran, S. N. A.; Zulkharnain, A.; Sunami, Y.

2018-01-01

Functional properties of shark denticles have caught the attention of engineers and scientist today due to the hydrodynamic effects of its skin surface roughness. The skin of a fast swimming shark reveals riblet structures that help to reduce skin friction drag, shear stresses, making its movement to be more efficient and faster. Inspired by the structure of the shark skin denticles, our team has conducted a study on alternative on improving the hydrodynamic design of marine vessels by applying the simplified version of shark skin skin denticles on the surface hull of the vessels. Models used for this study are constructed and computational fluid dynamic (CFD) simulations are then carried out to predict the effectiveness of the hydrodynamic effects of the biomimetic shark skins on those models. Interestingly, the numerical calculated results obtained shows that the presence of biomimetic shark skin implemented on the vessels give improvements in the maximum speed as well as reducing the drag force experience by the vessels. The pattern of the wave generated post cruising area behind the vessels can also be observed to reduce the wakes and eddies. Theoretically, reduction of drag force provides a more efficient vessel with a better cruising speed. To further improve on this study, the authors are now actively arranging an experimental procedure in order to verify the numerical results obtained by CFD. The experimental test will be carried out using an 8 metre flow channel provided by University Malaysia Sarawak, Malaysia.

MER surface fault protection system

NASA Technical Reports Server (NTRS)

Neilson, Tracy

2005-01-01

The Mars Exploration Rovers surface fault protection design was influenced by the fact that the solar-powered rovers must recharge their batteries during the day to survive the night. the rovers needed to autonomously maintain thermal stability, initiate safe and reliable communication with orbiting assets or directly to Earth, while maintaining energy balance. This paper will describe the system fault protection design for the surface phase of the mission.

Initial observations of cavitation-induced erosion of liquid metal spallation target vessels at the Spallation Neutron Source

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

McClintock, David A; Riemer, Bernie; Ferguson, Phillip D

2012-01-01

During operation of the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory the mechanical properties of the AISI 316L target module are altered by high-energy neutron and proton radiation. The interior surfaces of the target vessel are also damaged by cavitation-induced erosion, which results from repetitive rapid heating of the liquid mercury by high-energy proton beam pulses. Until recently no observations of cavitation-induced erosion were possible for conditions prototypical to the SNS. Post irradiation examination (PIE) of the first and second operational SNS targets was performed to gain insight into the radiation-induced changes in mechanical properties of the 316Lmore » target material and the extent of cavitation-induced erosion to the target vessel inner surfaces. Observations of cavitation-induced erosion of the first and second operational SNS target modules are presented here, including images of the target vessel interiors and specimens removed from the target beam-entrance regions.« less

Nitramine smokeless propellant research

NASA Technical Reports Server (NTRS)

Cohen, N. S.; Strand, L. P.

1977-01-01

A transient ballistics and combustion model is derived to represent the closed vessel experiment that is widely used to characterize propellants. A computer program is developed to solve the time-dependent equations, and is applied to explain aspects of closed vessel behavior. In the case of nitramine propellants the cratering of the burning surface associated with combustion above break-point pressures augments the effective burning rate as deduced from the closed vessel experiment. Low pressure combustion is significantly affected by the ignition process and, in the case of nitramine propellants, by the developing and changing surface structure. Thus, burning rates deduced from the closed vessel experiment may or may not agree with those measured in the equilibrium strand burner. Series of T burner experiments are performed to compare the combustion instability characteristics of nitramine (HMX) containing propellants and ammonium perchlorate (AP)propellants. Although ash produced by more fuel rich propellants could have provided mechanical suppression, results from clean-burning propellants permit the conclusion that HMX reduces the acoustic driving.

Using typical endoscopic features to diagnose esophageal squamous papilloma.

PubMed

Wong, Ming-Wun; Bair, Ming-Joug; Shih, Shou-Chuan; Chu, Cheng-Hsin; Wang, Horng-Yuan; Wang, Tsang-En; Chang, Chen-Wang; Chen, Ming-Jen

2016-02-21

To better understand some of the superficial tiny lesions that are recognized as squamous papilloma of the esophagus (SPE) and receive a different pathological diagnosis. All consecutive patients with esophageal polypoid lesions detected by routine endoscopy at our Endoscopy Centre between October 2009 and June 2014 were retrospectively analysed. We enrolled patients with SPE or other superficial lesions to investigate four key endoscopic appearances (whitish color, exophytic growth, wart-like shape, and surface vessels) and used narrow band imaging (NBI) to distinguish their differences. These series endoscopic images of each patient were retrospectively reviewed by three experienced endoscopists with no prior access to the images. All lesion specimens obtained by forceps biopsy were fixed in formalin and processed for pathological examination. The following data were collected from patient medical records: gender, age, indications for esophagogastroduodenoscopy, and endoscopic characteristics including lesion location, number, color, size, surface morphology, surrounding mucosa, and surface vessels under NBI. Clinicopathological features were also compared. During the study period, 41 esophageal polypoid lesions from 5698 endoscopic examinations were identified retrospectively. These included 24 patients with pathologically confirmed SPE, 11 patients with squamous hyperplasia, three patients with glycogenic acanthosis, two patients with ectopic sebaceous glands, and one patient with a xanthoma. In the χ (2) test, exophytic growth (P = 0.003), a wart-like shape (P < 0.001), and crossing surface vessels under NBI (P = 0.001) were more frequently observed in SPE than in other lesion types. By contrast, there was no significant difference regarding the appearance of a whitish color between SPE and other lesion types (P = 0.872). The most sensitive characteristic was wart-like projections (81.3%) and the most specific was exophytic growth (87.5%). Promising positive predictive values of 84.2%, 80.8%, and 82.6% were noted for exophytic growth, wart-like projections, and surface vessel crossing on NBI, respectively. The use of three key typical endoscopic appearances--exophytic growth, a wart-like shape, and vessel crossing on the lesion surface under NBI--has a promising positive predictive value of 88.2%. This diagnostic triad is useful for the endoscopic diagnosis of SPE.

Using typical endoscopic features to diagnose esophageal squamous papilloma

PubMed Central

Wong, Ming-Wun; Bair, Ming-Joug; Shih, Shou-Chuan; Chu, Cheng-Hsin; Wang, Horng-Yuan; Wang, Tsang-En; Chang, Chen-Wang; Chen, Ming-Jen

2016-01-01

AIM: To better understand some of the superficial tiny lesions that are recognized as squamous papilloma of the esophagus (SPE) and receive a different pathological diagnosis. METHODS: All consecutive patients with esophageal polypoid lesions detected by routine endoscopy at our Endoscopy Centre between October 2009 and June 2014 were retrospectively analysed. We enrolled patients with SPE or other superficial lesions to investigate four key endoscopic appearances (whitish color, exophytic growth, wart-like shape, and surface vessels) and used narrow band imaging (NBI) to distinguish their differences. These series endoscopic images of each patient were retrospectively reviewed by three experienced endoscopists with no prior access to the images. All lesion specimens obtained by forceps biopsy were fixed in formalin and processed for pathological examination. The following data were collected from patient medical records: gender, age, indications for esophagogastroduodenoscopy, and endoscopic characteristics including lesion location, number, color, size, surface morphology, surrounding mucosa, and surface vessels under NBI. Clinicopathological features were also compared. RESULTS: During the study period, 41 esophageal polypoid lesions from 5698 endoscopic examinations were identified retrospectively. These included 24 patients with pathologically confirmed SPE, 11 patients with squamous hyperplasia, three patients with glycogenic acanthosis, two patients with ectopic sebaceous glands, and one patient with a xanthoma. In the χ2 test, exophytic growth (P = 0.003), a wart-like shape (P < 0.001), and crossing surface vessels under NBI (P = 0.001) were more frequently observed in SPE than in other lesion types. By contrast, there was no significant difference regarding the appearance of a whitish color between SPE and other lesion types (P = 0.872). The most sensitive characteristic was wart-like projections (81.3%) and the most specific was exophytic growth (87.5%). Promising positive predictive values of 84.2%, 80.8%, and 82.6% were noted for exophytic growth, wart-like projections, and surface vessel crossing on NBI, respectively. CONCLUSION: The use of three key typical endoscopic appearances - exophytic growth, a wart-like shape, and vessel crossing on the lesion surface under NBI - has a promising positive predictive value of 88.2%. This diagnostic triad is useful for the endoscopic diagnosis of SPE. PMID:26900297

Tadpole-like artificial micromotor

NASA Astrophysics Data System (ADS)

Liu, Limei; Liu, Mei; Su, Yajun; Dong, Yonggang; Zhou, Wei; Zhang, Lina; Zhang, Hui; Dong, Bin; Chi, Lifeng

2015-01-01

We describe a polymer-based artificial tadpole-like micromotor, which is fabricated through the electrospinning technique. By incorporating functional materials onto its surface or within its body, the resulting tadpole-like micromotor can not only move autonomously in an aqueous solution with a flexible tail, but also exhibit thermo- and magnetic responsive properties.We describe a polymer-based artificial tadpole-like micromotor, which is fabricated through the electrospinning technique. By incorporating functional materials onto its surface or within its body, the resulting tadpole-like micromotor can not only move autonomously in an aqueous solution with a flexible tail, but also exhibit thermo- and magnetic responsive properties. Electronic supplementary information (ESI) available: Experimental section, Fig. S1-S3 and Video S1-S4. See DOI: 10.1039/c4nr06621a

Sensitive enhancement of vessel wall imaging with an endoesophageal Wireless Amplified NMR Detector (WAND).

PubMed

Zeng, Xianchun; Barbic, Mladen; Chen, Liangliang; Qian, Chunqi

2017-11-01

To improve the imaging quality of vessel walls with an endoesophageal Wireless Amplified NMR Detector (WAND). A cylindrically shaped double-frequency resonator has been constructed with a single metal wire that is self-connected by a pair of nonlinear capacitors. The double-frequency resonator can convert wirelessly provided pumping power into amplified MR signals. This compact design makes the detector easily insertable into a rodent esophagus. The detector has good longitudinal and axial symmetry. Compared to an external surface coil, the WAND can enhance detection sensitivity by at least 5 times, even when the distance separation between the region of interest and the detector's cylindrical surface is twice the detector's own radius. Such detection capability enables us to observe vessel walls near the aortic arch and carotid bifurcation with elevated sensitivity. A cylindrical MRI detector integrated with a wireless-powered amplifier has been developed as an endoesophageal detector to enhance detection sensitivity of vessel walls. This detector can greatly improve the imaging quality for vessel regions that are susceptible to atherosclerotic lesions. Magn Reson Med 78:2048-2054, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Design of a Vision-Based Sensor for Autonomous Pig House Cleaning

NASA Astrophysics Data System (ADS)

Braithwaite, Ian; Blanke, Mogens; Zhang, Guo-Qiang; Carstensen, Jens Michael

2005-12-01

Current pig house cleaning procedures are hazardous to the health of farm workers, and yet necessary if the spread of disease between batches of animals is to be satisfactorily controlled. Autonomous cleaning using robot technology offers salient benefits. This paper addresses the feasibility of designing a vision-based system to locate dirty areas and subsequently direct a cleaning robot to remove dirt. Novel results include the characterisation of the spectral properties of real surfaces and dirt in a pig house and the design of illumination to obtain discrimination of clean from dirty areas with a low probability of misclassification. A Bayesian discriminator is shown to be efficient in this context and implementation of a prototype tool demonstrates the feasibility of designing a low-cost vision-based sensor for autonomous cleaning.

AUV and Aircraft Measurements of an Internal Hydraulic Jump at the Mouth of the Columbia River

NASA Astrophysics Data System (ADS)

McNeil, C. L.

2016-02-01

In 2013, an extensive 3-km long persistent hydraulic jump in the Mouth of the Columbia River (MCR) was captured in a joint pilot study involving coordinated autonomous and remote sensing observations. Airborne thermal infrared (IR) cameras provided observations of surface brightness temperature, while an along-track interferometric synthetic aperture radar (ATI-SAR) measured surface velocity and roughness. Subsurface hydrographic surveys were conducted with a REMUS autonomous underwater vehicle (AUV). These observations showed a flow- oblique stationary front that persisted through most of an ebb-tide. A pronounced dip and divergence (mixing) of the isohaline surfaces downstream of the surface front suggested that the newly-discovered feature is an internal hydraulic jump. Hydraulic jumps reduce kinetic energy of a laminar flow, partially converting it to turbulent kinetic energy that, in turn, increases the potential energy of the system via mixing. Our goal is to quantify this mixing associated with the MCR jump using our existing data, and more generally assess the jump's impact on the physics and biology of the lower estuary, plume, and coastal ocean.

Aluminum and Other Coatings for the Passivation of Tritium Storage Vessels

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

Spencer, W.; Korinko, P.

Using a highly sensitive residual gas analyzer, the off-gassing of hydrogen, water, and hydrocarbons from surface-treated storage vessels containing deuterium was measured. The experimental storage vessels were compared to a low-off-gassing, electro-polished 304L canister. Alternative vessels were made out of aluminum, or were coatings on 304L steel. Coatings included powder pack aluminide, electro-plated aluminum, powder pack chromide, dense electro-plated chromium, copper plated, and copper plated with 25 and 50 percent nano-diamond. Vessels were loaded with low pressure deuterium to observe exchange with protium or hydrogen as observed with formation of HD and HDO. Off gas of D 2O or possiblemore » CD 4 was observed at mass 20. The main off-gas in all of the studies was H 2. The studies indicated that coatings required significant post-coating treatment to reduce off-gas and enhance the permeation barrier from gases likely added during the coating process. Dense packed aluminum coatings needed heating to drive off water. Electro-plated aluminum, chromium and copper coatings appeared to trap hydrogen from the plating process. Nano-diamond appeared to enhance the exchange rate with hydrogen off gas, and its coating process trapped significant amounts of hydrogen. Aluminum caused more protium exchange than chromium-treated surfaces. Aluminum coatings released more water, but pure aluminum vessels released small amounts of hydrogen, little water, and generally performed well. Chromium coating had residual hydrogen that was difficult to totally outgas but otherwise gave low residuals for water and hydrocarbons. Our studies indicated that simple coating of as received 304L metal will not adequately block hydrogen. The base vessel needs to be carefully out-gassed before applying a coating, and the coating process will likely add additional hydrogen that must be removed. Initial simple bake-out and leak checks up to 350° C for a few hours was found to be inadequate. All of the studies indicated that vessels needed several days of vacuum baking at 350-450° C to fully outgas the residual gases, which were mostly hydrogen. The current standard practice of out-gassing from ultra-clean, electro-polished 304L vessels with both vacuum bake-out and followed by an oxidative bake out to enhance the chromium surface performed the best in these studies.« less

Quick actuating closure

NASA Technical Reports Server (NTRS)

White, III, Dorsey E. (Inventor); Updike, deceased, Benjamin T. (Inventor); Allred, Johnny W. (Inventor)

1989-01-01

A quick actuating closure for a pressure vessel 80 in which a wedge ring 30 with a conical outer surface 31 is moved forward to force shear blocks 40, with conical inner surfaces 41, radially outward to lock an end closure plug 70 within an opening 81 in the pressure vessel 80. A seal ring 60 and a preload ramp 50 sit between the shear blocks 40 and the end closure plug 70 to provide a backup sealing capability. Conical surfaces 44 and 55 of the preload ramp 50 and the shear blocks 40 interact to force the seal ring 60 into shoulders 73 and 85 in the end closure plug 70 and opening 81 to form a tight seal. The end closure plug 70 is unlocked by moving the wedge ring 30 rearward, which causes T-bars 32 of the wedge ring 30 riding within T -slots 42 of the shear blocks 40 to force them radially inward. The end closure plug 70 is then removed, allowing access to the interior of the pressure vessel 80.

33 CFR 164.35 - Equipment: All vessels.

Code of Federal Regulations, 2012 CFR

2012-07-01

... must have the following: (a) A marine radar system for surface navigation. (b) An illuminated magnetic... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Equipment: All vessels. 164.35 Section 164.35 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED...

NON-CORROSIVE REACTOR FUEL SYSTEM

DOEpatents

Herrick, C.C.

1962-08-14

A non-corrosive nuclear reactor fuel system was developed utilizing a molten plutonium-- iron alloy fuel having about 2 at.% carbon and contained in a tantalum vessel. This carbon reacts with the interior surface of the tantalum vessel to form a plutonium resistant self-healing tantalum carbide film. (AEC)

GOLD PRESSURE VESSEL SEAL

DOEpatents

Smith, A.E.

1963-11-26

An improved seal between the piston and die member of a piston-cylinder type pressure vessel is presented. A layer of gold, of sufficient thickness to provide an interference fit between the piston and die member, is plated on the contacting surface of at least one of the members. (AEC)

Autonomous selection of PDE inpainting techniques vs. exemplar inpainting techniques for void fill of high resolution digital surface models

NASA Astrophysics Data System (ADS)

Rahmes, Mark; Yates, J. Harlan; Allen, Josef DeVaughn; Kelley, Patrick

2007-04-01

High resolution Digital Surface Models (DSMs) may contain voids (missing data) due to the data collection process used to obtain the DSM, inclement weather conditions, low returns, system errors/malfunctions for various collection platforms, and other factors. DSM voids are also created during bare earth processing where culture and vegetation features have been extracted. The Harris LiteSite TM Toolkit handles these void regions in DSMs via two novel techniques. We use both partial differential equations (PDEs) and exemplar based inpainting techniques to accurately fill voids. The PDE technique has its origin in fluid dynamics and heat equations (a particular subset of partial differential equations). The exemplar technique has its origin in texture analysis and image processing. Each technique is optimally suited for different input conditions. The PDE technique works better where the area to be void filled does not have disproportionately high frequency data in the neighborhood of the boundary of the void. Conversely, the exemplar based technique is better suited for high frequency areas. Both are autonomous with respect to detecting and repairing void regions. We describe a cohesive autonomous solution that dynamically selects the best technique as each void is being repaired.

Refractory lining system for high wear area of high temperature reaction vessel

DOEpatents

Hubble, David H.; Ulrich, Klaus H.

1998-01-01

A refractory-lined high temperature reaction vessel comprises a refractory ring lining constructed of refractory brick, a cooler, and a heat transfer medium disposed between the refractory ring lining and the cooler. The refractory brick comprises magnesia (MgO) and graphite. The heat transfer medium contacts the refractory brick and a cooling surface of the cooler, and is composed of a material that accommodates relative movement between the refractory brick and the cooler. The brick is manufactured such that the graphite has an orientation providing a high thermal conductivity in the lengthwise direction through the brick that is higher than the thermal conductivity in directions perpendicular to the lengthwise direction. The graphite preferably is flake graphite, in the range of about 10 to 20 wt %, and has a size distribution selected to provide maximum brick density. The reaction vessel may be used for performing a reaction process including the steps of forming a layer of slag on a melt in the vessel, the slag having a softening point temperature range, and forming a protective frozen layer of slag on the interior-facing surface of the refractory lining in at least a portion of a zone where the surface contacts the layer of slag, the protective frozen layer being maintained at or about the softening point of the slag.

Inner and outer coronary vessel wall segmentation from CCTA using an active contour model with machine learning-based 3D voxel context-aware image force

NASA Astrophysics Data System (ADS)

Sivalingam, Udhayaraj; Wels, Michael; Rempfler, Markus; Grosskopf, Stefan; Suehling, Michael; Menze, Bjoern H.

2016-03-01

In this paper, we present a fully automated approach to coronary vessel segmentation, which involves calcification or soft plaque delineation in addition to accurate lumen delineation, from 3D Cardiac Computed Tomography Angiography data. Adequately virtualizing the coronary lumen plays a crucial role for simulating blood ow by means of fluid dynamics while additionally identifying the outer vessel wall in the case of arteriosclerosis is a prerequisite for further plaque compartment analysis. Our method is a hybrid approach complementing Active Contour Model-based segmentation with an external image force that relies on a Random Forest Regression model generated off-line. The regression model provides a strong estimate of the distance to the true vessel surface for every surface candidate point taking into account 3D wavelet-encoded contextual image features, which are aligned with the current surface hypothesis. The associated external image force is integrated in the objective function of the active contour model, such that the overall segmentation approach benefits from the advantages associated with snakes and from the ones associated with machine learning-based regression alike. This yields an integrated approach achieving competitive results on a publicly available benchmark data collection (Rotterdam segmentation challenge).

Overall behaviour of PFC integrated SST-1 vacuum system

NASA Astrophysics Data System (ADS)

Khan, Ziauddin; Raval, Dilip C.; Paravasu, Yuvakiran; Semwal, Pratibha; Dhanani, Kalpeshkumar R.; George, Siju; Shoaib, Mohammad; Prakash, Arun; Babu, Gattu R.; Thankey, Prashant; Pathan, Firozkhan S.; Pradhan, Subrata

2017-04-01

As a part of phase-I up-gradation of Steady-state Superconducting Tokamak (SST-1), Graphite Plasma Facing Components (PFCs) have been integrated inside SST-1 vacuum vessel as a first wall (FW) during Nov 14 and May 2015. The SST-1 FW has a total surface area of the installed PFCs exposed to plasma is ∼ 40 m2 which is nearly 50% of the total surface area of stainless steel vacuum chamber (∼75 m2). The volume of the vessel within the PFCs is ∼ 16 m3. After the integration of PFCs, the entire vessel as well as the PFC cooling/baking circuits has been qualified with an integrated helium leak tightness of < 1.0 x 10-8 mbar 1/s. The pumping system of the SST-1 vacuum vessel comprises of one number of Roots’ pump, four numbers of turbomolecular pumps and a cryopump. After the initial pump down, the PFCs were baked at 250 °C for nearly 20 hours employing hot nitrogen gas to remove the absorbed water vapours. Thereafter, Helium glow discharges cleaning were carried out towards the removal of surface impurities. The pump down characteristics of SST-1 vacuum chamber and the changes in the residual gaseous impurities after the installation of the PFCs will be discussed in this paper.

Critical heat flux (CHF) phenomenon on a downward facing curved surface

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

Cheung, F.B.; Haddad, K.H.; Liu, Y.C.

1997-06-01

This report describes a theoretical and experimental study of the boundary layer boiling and critical heat flux phenomena on a downward facing curved heating surface, including both hemispherical and toroidal surfaces. A subscale boundary layer boiling (SBLB) test facility was developed to measure the spatial variation of the critical heat flux and observe the underlying mechanisms. Transient quenching and steady-state boiling experiments were performed in the SBLB facility under both saturated and subcooled conditions to obtain a complete database on the critical heat flux. To complement the experimental effort, an advanced hydrodynamic CHF model was developed from the conservation lawsmore » along with sound physical arguments. The model provides a clear physical explanation for the spatial variation of the CHF observed in the SBLB experiments and for the weak dependence of the CHF data on the physical size of the vessel. Based upon the CHF model, a scaling law was established for estimating the local critical heat flux on the outer surface of a heated hemispherical vessel that is fully submerged in water. The scaling law, which compares favorably with all the available local CHF data obtained for various vessel sizes, can be used to predict the local CHF limits on large commercial-size vessels. This technical information represents one of the essential elements that is needed in assessing the efficacy of external cooling of core melt by cavity flooding as a severe accident management strategy. 83 figs., 3 tabs.« less

Disruption of miR-29 Leads to Aberrant Differentiation of Smooth Muscle Cells Selectively Associated with Distal Lung Vasculature.

PubMed

Cushing, Leah; Costinean, Stefan; Xu, Wei; Jiang, Zhihua; Madden, Lindsey; Kuang, Pingping; Huang, Jingshu; Weisman, Alexandra; Hata, Akiko; Croce, Carlo M; Lü, Jining

2015-05-01

Differentiation of lung vascular smooth muscle cells (vSMCs) is tightly regulated during development or in response to challenges in a vessel specific manner. Aberrant vSMCs specifically associated with distal pulmonary arteries have been implicated in the pathogenesis of respiratory diseases, such as pulmonary arterial hypertension (PAH), a progressive and fatal disease, with no effective treatment. Therefore, it is highly relevant to understand the underlying mechanisms of lung vSMC differentiation. miRNAs are known to play critical roles in vSMC maturation and function of systemic vessels; however, little is known regarding the role of miRNAs in lung vSMCs. Here, we report that miR-29 family members are the most abundant miRNAs in adult mouse lungs. Moreover, high levels of miR-29 expression are selectively associated with vSMCs of distal vessels in both mouse and human lungs. Furthermore, we have shown that disruption of miR-29 in vivo leads to immature/synthetic vSMC phenotype specifically associated with distal lung vasculature, at least partially due to the derepression of KLF4, components of the PDGF pathway and ECM-related genes associated with synthetic phenotype. Moreover, we found that expression of FBXO32 in vSMCs is significantly upregulated in the distal vasculature of miR-29 null lungs. This indicates a potential important role of miR-29 in smooth muscle cell function by regulating FBXO32 and SMC protein degradation. These results are strongly supported by findings of a cell autonomous role of endogenous miR-29 in promoting SMC differentiation in vitro. Together, our findings suggested a vessel specific role of miR-29 in vSMC differentiation and function by targeting several key negative regulators.

40 CFR 63.134 - Process wastewater provisions-surface impoundments.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Process wastewater provisions-surface... Manufacturing Industry for Process Vents, Storage Vessels, Transfer Operations, and Wastewater § 63.134 Process wastewater provisions—surface impoundments. (a) For each surface impoundment that receives, manages, or...

Marbles for the Imagination

NASA Technical Reports Server (NTRS)

Shue, Jack

2004-01-01

The end-to-end test would verify the complex sequence of events from lander separation to landing. Due to the large distances involved and the significant delay time in sending a command and receiving verification, the lander needed to operate autonomously after it separated from the orbiter. It had to sense conditions, make decisions, and act accordingly. We were flying into a relatively unknown set of conditions-a Martian atmosphere of unknown pressure, density, and consistency to land on a surface of unknown altitude, and one which had an unknown bearing strength. In order to touch down safely on Mars the lander had to orient itself for descent and entry, modulate itself to maintain proper lift, pop a parachute, jettison its aeroshell, deploy landing legs and radar, ignite a terminal descent engine, and fly a given trajectory to the surface. Once on the surface, it would determine its orientation, raise the high-gain antenna, perform a sweep to locate Earth, and begin transmitting information. It was this complicated, autonomous sequence that the end-to-end test was to simulate.

A network of autonomous surface ozone monitors in Antarctica: technical description and first results

NASA Astrophysics Data System (ADS)

Bauguitte, S. J.; Brough, N.; Frey, M. M.; Jones, A. E.; Roscoe, H. K.; Wolff, E. W.

2009-12-01

Concentrations of surface ozone over polar regions cannot be derived from satellite data so can only be studied from ground-based platforms. To understand the regional picture a carefully-designed network of ground-based monitors is required. Here we report on a network of 10 autonomous ozone monitors that was established around the Weddell Sea sector of coastal Antarctica with a transect up onto the Antarctic Plateau during the International Polar Year. The aim was to measure for a full year, thus gaining a much-improved broader view of boundary layer ozone seasonality at different locations as well as on factors affecting the budget of surface ozone in Antarctica. Of specific interest were the balance between halogen-driven destruction and photochemical production from snow-emitted precursors, as well as the spatial extent of ozone depletion events. Each ozone monitor measured successfully within its predefined duty cycle throughout the year, with some differences in performance dependent on power availability. Here we present technical information and first results from the network.

ED07-0210-3

NASA Image and Video Library

2007-09-13

The instruments that make up the Ames Autonomous Module Scanner (AMS) that provided precise thermal-infrared imaging during the Western States Fire Mission in 2007 are detailed in this photo of the AMS as mounted on Ikhana's pod tray. The large foil-covered foam-insulated box at left covers the pressure vessel containing the data system computers and other electronics. The round white-topped assembly is the scan head, including the scan mirror, folded telescope, blackbody references, spectrometer and detectors. Two pressure boxes visible at the forward end of the tray contain the Applanix POS/AV precision navigation subsystem (black) and the power distributor including circuit breakers and ancillary wiring, scan motor controller and the blackbody reference temperature controller (blue).

Observing the seasonal cycle of the upper ocean in the Ross Sea, Antarctica, with autonomous profiling floats

NASA Astrophysics Data System (ADS)

Porter, D. F.; Springer, S. R.; Padman, L.; Fricker, H. A.; Bell, R. E.

2017-12-01

The upper layers of the Southern Ocean where it meets the Antarctic ice sheet undergoes a large seasonal cycle controlled by surface radiation and by freshwater fluxes, both of which are strongly influenced by sea ice. In regions where seasonal sea ice and icebergs limit use of ice-tethered profilers and conventional moorings, autonomous profiling floats can sample the upper ocean. The deployment of seven Apex floats (by sea) and six ALAMO floats (by air) provides unique upper ocean hydrographic data in the Ross Sea close to the Ross Ice Shelf front. A novel choice of mission parameters - setting parking depth deeper than the seabed - limits their drift, allowing us to deploy the floats close to the ice shelf front, while sea ice avoidance algorithms allow the floats to to sample through winter under sea ice. Hydrographic profiles show the detailed development of the seasonal mixed layer close to the Ross front, and interannual variability of the seasonal mixed layer and deeper water masses on the central Ross Sea continental shelf. After the sea ice breakup in spring, a warm and fresh surface mixed layer develops, further warming and deepening throughout the summer. The mixed layer deepens, with maximum temperatures exceeding 0ºC in mid-February. By March, the surface energy budget becomes negative and sea ice begins to form, creating a cold, saline and dense surface layer. Once these processes overcome the stable summer stratification, convection erodes the surface mixed layer, mixing some heat downwards to deeper layers. There is considerable interannual variability in the evolution and strength of the surface mixed layer: summers with shorter ice-free periods result in a cooler and shallower surface mixed layer, which accumulates less heat than the summers with longer ice-free periods. Early ice breakup occurred in all floats in 2016/17 summer, enhancing the absorbed solar flux leading to a warmer surface mixed layer. Together, these unique measurements from autonomous profilers provide insight into the hydrographic state of the Ross Sea at the start of the spring period of sea-ice breakup, and how ocean mixing and sea ice interact to initiate the summer open-water season.

High-autonomy control of space resource processing plants

NASA Technical Reports Server (NTRS)

Schooley, Larry C.; Zeigler, Bernard P.; Cellier, Francois E.; Wang, Fei-Yue

1993-01-01

A highly autonomous intelligent command/control architecture has been developed for planetary surface base industrial process plants and Space Station Freedom experimental facilities. The architecture makes use of a high-level task-oriented mode with supervisory control from one or several remote sites, and integrates advanced network communications concepts and state-of-the-art man/machine interfaces with the most advanced autonomous intelligent control. Attention is given to the full-dynamics model of a Martian oxygen-production plant, event-based/fuzzy-logic process control, and fault management practices.

An advanced terrain modeler for an autonomous planetary rover

NASA Technical Reports Server (NTRS)

Hunter, E. L.

1980-01-01

A roving vehicle capable of autonomously exploring the surface of an alien world is under development and an advanced terrain modeler to characterize the possible paths of the rover as hazardous or safe is presented. This advanced terrain modeler has several improvements over the Troiani modeler that include: a crosspath analysis, better determination of hazards on slopes, and methods for dealing with missing returns at the extremities of the sensor field. The results from a package of programs to simulate the roving vehicle are then examined and compared to results from the Troiani modeler.

Autonomous Experimentation of Carbon Nanotube Using Response Surface Methods

DTIC Science & Technology

2015-03-26

on the unique challenges of creating autonomous research robots . v Table of Contents Page Abstract...previous RSM results. 31 S AR Reset a l data les Disp ay Sta t Menu Adjust eas ble bounda es Ad ust acto evel size Dec de andom o speci ed n t...al sta t ni ial Sta t Gene ate andom sta t # o uns D splay O Block Menu C ea e O B ock des gn Disp ay ull O Design Menu C ea e O ull Design W

46 CFR 174.080 - Flooding on self-elevating and surface type units.

Code of Federal Regulations, 2010 CFR

2010-10-01

... STABILITY SPECIAL RULES PERTAINING TO SPECIFIC VESSEL TYPES Special Rules Pertaining to Mobile Offshore Drilling Units § 174.080 Flooding on self-elevating and surface type units. (a) On a surface type unit or...

46 CFR 174.080 - Flooding on self-elevating and surface type units.

Code of Federal Regulations, 2013 CFR

2013-10-01

... STABILITY SPECIAL RULES PERTAINING TO SPECIFIC VESSEL TYPES Special Rules Pertaining to Mobile Offshore Drilling Units § 174.080 Flooding on self-elevating and surface type units. (a) On a surface type unit or...

Automatic retinal blood vessel parameter calculation in spectral domain optical coherence tomography

NASA Astrophysics Data System (ADS)

Wehbe, Hassan; Ruggeri, Marco; Jiao, Shuliang; Gregori, Giovanni; Puliafito, Carmen A.

2007-02-01

Measurement of retinal blood vessel parameters like the blood blow in the vessels may have significant impact on the study and diagnosis of glaucoma, a leading blinding disease worldwide. Optical coherence tomography (OCT) is a noninvasive imaging technique that can provide not only microscopic structural imaging of the retina but also functional information like the blood flow velocity in the retina. The aim of this study is to automatically extract the parameters of retinal blood vessels like the 3D orientation, the vessel diameters, as well as the corresponding absolute blood flow velocity in the vessel. The parameters were extracted from circular OCT scans around the optic disc. By removing the surface reflection through simple segmentation of the circular OCT scans a blood vessel shadowgram can be generated. The lateral coordinates and the diameter of each blood vessel are extracted from the shadowgram through a series of signal processing. Upon determination of the lateral position and the vessel diameter, the coordinate in the depth direction of each blood vessel is calculated in combination with the Doppler information for the vessel. The extraction of the vessel coordinates and diameter makes it possible to calculate the orientation of the vessel in reference to the direction of the incident sample light, which in turn can be used to calculate the absolute blood flow velocity and the flow rate.

Electrical stimulation of acupuncture points and blood pressure responses to postural changes: a pilot study.

PubMed

Jones, Alice Y M; Kwan, Y L; Leung, Nathan T F; Yu, Rachel P W; Wu, Cindy M Y; Warburton, Darren E R

2011-05-01

Application of transcutaneous electrical stimulation over acupuncture points (Acu-TENS) facilitates heart rate recovery after exercise and restores hemodynamic stability after open heart surgery. The role of Acu-TENS on cardiovascular parameters in response to postural changes has not been reported. To investigate (1) the effect of Acu-TENS on blood pressure responses to -10º head-down postural change and (2) whether such effects were associated with modulation by the autonomic nervous system. Sixteen healthy volunteers, mean age 22.8 (SD, 3.1) years, were subjected to a -10º head-down tilt from the supine position on 3 separate occasions and received in random order the following 3 intervention protocols for 40 minutes before the postural change: Acu-TENS (over bilateral acupuncture points, PC6), sham-TENS (TENS applied to the skin over the patellae), and control (no electrical output from the TENS device applied at PC6). Mean arterial pressure, large artery elasticity index, cardiac output, and heart rate were recorded and compared at different stimulation protocols in the supine and -10º head-down tilt positions. Spectral analysis of heart rate variability was used to determine any modulation by the autonomic nervous system. Change in large artery elasticity index was observed only in the Acu-TENS group (P < .05) and mean arterial pressure appeared most stable during Acu-TENS. Autonomic nervous system modulation was not apparent with spectral analysis, irrespective of intervention. Sympathetic activity predominated in all positions. Acu-TENS seems to reduce blood pressure changes with -10º head-down tilt with concomitant changes in arterial vessel tone.

Measuring shear force transmission across a biomimetic glycocalyx

NASA Astrophysics Data System (ADS)

Bray, Isabel; Young, Dylan; Scrimgeour, Jan

Human blood vessels are lined with a low-density polymer brush known as the glycocalyx. This brush plays an active role in defining the mechanical and biochemical environment of the endothelial cell in the blood vessel wall. In addition, it is involved in the detection of mechanical stimuli, such as the shear stress from blood flowing in the vessel. In this work, we construct a biomimetic version of the glycocalyx on top of a soft deformable substrate in order to measure its ability to modulate the effects of shear stress at the endothelial cell surface. The soft substrate is stamped on to a glass substrate and then enclosed inside a microfluidic device that generates a controlled flow over the substrate. The hydrogel chemistry has been optimized so that it reliably stamps into a defined shape and has consistent mechanical properties. Fluorescent microbeads embedded in the gel allow measurement of the surface deformation, and subsequently, calculation of the shear force at the surface of the soft substrate. We investigate the effect of the major structural elements of the glycocalyx, hyaluronic acid and charged proteoglycans, on the magnitude of the shear force transmitted to the surface of the hydrogel.

50 CFR 218.104 - Mitigation.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Bombing Exercises (explosive bombs and rockets): (i) If surface vessels are involved, trained lookouts... within the buffer zone. (12) Air-to-Surface At-Sea Bombing Exercises (Non-explosive Bombs and Rockets...

Analysis and Visualization of Nerve Vessel Contacts for Neurovascular Decompression

NASA Astrophysics Data System (ADS)

Süßmuth, Jochen; Piazza, Alexander; Enders, Frank; Naraghi, Ramin; Greiner, Günther; Hastreiter, Peter

Neurovascular compression syndromes are caused by a pathological contact between cranial nerves and vascular structures at the surface of the brainstem. Aiming at improved pre-operative analysis of the target structures, we propose calculating distance fields to provide quantitative information of the important nerve-vessel contacts. Furthermore, we suggest reconstructing polygonal models for the nerves and vessels. Color-coding with the respective distance information is used for enhanced visualization. Overall, our new strategy contributes to a significantly improved clinical understanding.

Device for inspecting vessel surfaces

DOEpatents

Appel, D. Keith

1995-01-01

A portable, remotely-controlled inspection crawler for use along the walls of tanks, vessels, piping and the like. The crawler can be configured to use a vacuum chamber for supporting itself on the inspected surface by suction or a plurality of magnetic wheels for moving the crawler along the inspected surface. The crawler is adapted to be equipped with an ultrasonic probe for mapping the structural integrity or other characteristics of the surface being inspected. Navigation of the crawler is achieved by triangulation techniques between a signal transmitter on the crawler and a pair of microphones attached to a fixed, remote location, such as the crawler's deployment unit. The necessary communications are established between the crawler and computers external to the inspection environment for position control and storage and/or monitoring of data acquisition.

Passive containment cooling water distribution device

DOEpatents

Conway, Lawrence E.; Fanto, Susan V.

1994-01-01

A passive containment cooling system for a nuclear reactor containment vessel. Disclosed is a cooling water distribution system for introducing cooling water by gravity uniformly over the outer surface of a steel containment vessel using a series of radial guide elements and cascading weir boxes to collect and then distribute the cooling water into a series of distribution areas through a plurality of cascading weirs. The cooling water is then uniformly distributed over the curved surface by a plurality of weir notches in the face plate of the weir box.

Quantification of Processing Effects on Filament Wound Pressure Vessels

NASA Technical Reports Server (NTRS)

Aiello, Robert A.; Chamis, Christos C.

1999-01-01

A computational simulation procedure is described which is designed specifically for the modeling and analysis of filament wound pressure vessels. Cylindrical vessels with spherical or elliptical end caps can be generated automatically. End caps other than spherical or elliptical may be modeled by varying circular sections along the x-axis according to the C C! end cap shape. The finite element model generated is composed of plate type quadrilateral shell elements on the entire vessel surface. This computational procedure can also be sued to generate grid, connectivity and material cards (bulk data) for component parts of a larger model. These bulk data are assigned to a user designated file for finite element structural/stress analysis of composite pressure vessels. The procedure accommodates filament would pressure vessels of all types of shells-of-revolution. It has provisions to readily evaluate initial stresses due to pretension in the winding filaments and residual stresses due to cure temperature.

Quantification of Processing Effects on Filament Wound Pressure Vessels. Revision

NASA Technical Reports Server (NTRS)

Aiello, Robert A.; Chamis, Christos C.

2002-01-01

A computational simulation procedure is described which is designed specifically for the modeling and analysis of filament wound pressure vessels. Cylindrical vessels with spherical or elliptical end caps can be generated automatically. End caps other than spherical or elliptical may be modeled by varying circular sections along the x-axis according to the end cap shape. The finite element model generated is composed of plate type quadrilateral shell elements on the entire vessel surface. This computational procedure can also be used to generate grid, connectivity and material cards (bulk data) for component parts of a larger model. These bulk data are assigned to a user designated file for finite element structural/stress analysis of composite pressure vessels. The procedure accommodates filament wound pressure vessels of all types of shells-of -revolution. It has provisions to readily evaluate initial stresses due to pretension in the winding filaments and residual stresses due to cure temperature.

Containment system for supercritical water oxidation reactor

DOEpatents

Chastagner, Philippe

1994-01-01

A system for containment of a supercritical water oxidation reactor in the event of a rupture of the reactor. The system includes a containment for housing the reaction vessel and a communicating chamber for holding a volume of coolant, such as water. The coolant is recirculated and sprayed to entrain and cool any reactants that might have escaped from the reaction vessel. Baffles at the entrance to the chamber prevent the sprayed coolant from contacting the reaction vessel. An impact-absorbing layer is positioned between the vessel and the containment to at least partially absorb momentum of any fragments propelled by the rupturing vessel. Remote, quick-disconnecting fittings exterior to the containment, in cooperation with shut-off valves, enable the vessel to be isolated and the system safely taken off-line. Normally-closed orifices throughout the containment and chamber enable decontamination of interior surfaces when necessary.

Containment system for supercritical water oxidation reactor

DOEpatents

Chastagner, P.

1994-07-05

A system is described for containment of a supercritical water oxidation reactor in the event of a rupture of the reactor. The system includes a containment for housing the reaction vessel and a communicating chamber for holding a volume of coolant, such as water. The coolant is recirculated and sprayed to entrain and cool any reactants that might have escaped from the reaction vessel. Baffles at the entrance to the chamber prevent the sprayed coolant from contacting the reaction vessel. An impact-absorbing layer is positioned between the vessel and the containment to at least partially absorb momentum of any fragments propelled by the rupturing vessel. Remote, quick-disconnecting fittings exterior to the containment, in cooperation with shut-off valves, enable the vessel to be isolated and the system safely taken off-line. Normally-closed orifices throughout the containment and chamber enable decontamination of interior surfaces when necessary. 2 figures.

Studies on in-vessel debris coolability in ALPHA program

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

Maruyama, Yu; Yamano, Norihiro; Moriyama, Kiyofumi

1997-02-01

In-vessel debris coolability experiments have been performed in ALPHA Program at JAERI. Aluminum oxide (Al{sub 2}O{sub 3}) produced by a thermite reaction was applied as a debris simulant. Two scoping experiments using approximately 30 kg or 50 kg of Al{sub 2}O{sub 3} were conducted. In addition to post-test observations, temperature histories of the debris simulant and the lower head experimental vessel were evaluated. Rapid temperature reduction observed on the outer surface of the experimental vessel may imply that water penetration into a gap between the solidified debris and the experimental vessel occurred resulting in an effective cooling of once heatedmore » vessel wall. Preliminary measurement of a gap width was made with an ultrasonic device. Signals to show the existence of gaps, ranging from 0.7 mm to 1.4 mm, were detected at several locations.« less

A Navigation Safety Support Model for the Strait of Istanbul

NASA Astrophysics Data System (ADS)

Yazici, M. Anil; Otay, Emre N.

In this study, a real time maritime traffic support model is developed for safe navigation in the Strait of Istanbul, also known as the Bosporus. The present model simulates vessel trajectories corresponding to possible headings, using channel geometry, counter traffic, and surface currents as input. A new MATLAB code is developed for the simulation and the Marine GNC Toolbox (Fossen and Perez, 2004) is used for the vessel hydrodynamics and the auto-pilot model. After computing the trajectory tree of the vessel by forward-mapping its position distribution with respect to the initial position vector, the casualty probabilities of each trajectory are found. Within certain restrictions on vessel geometry, the proposed model predicts the safest possible intended course for the transit vessels based on the navigational parameters including position, speed, and course of the vessel. The model is tested for the Strait of Istanbul for validation. Without loss of generality, the model can be used for any narrow channel with a vessel traffic system providing the necessary input.

An autonomous dynamical system captures all LCSs in three-dimensional unsteady flows.

PubMed

Oettinger, David; Haller, George

2016-10-01

Lagrangian coherent structures (LCSs) are material surfaces that shape the finite-time tracer patterns in flows with arbitrary time dependence. Depending on their deformation properties, elliptic and hyperbolic LCSs have been identified from different variational principles, solving different equations. Here we observe that, in three dimensions, initial positions of all variational LCSs are invariant manifolds of the same autonomous dynamical system, generated by the intermediate eigenvector field, ξ 2 (x 0 ), of the Cauchy-Green strain tensor. This ξ 2 -system allows for the detection of LCSs in any unsteady flow by classical methods, such as Poincaré maps, developed for autonomous dynamical systems. As examples, we consider both steady and time-aperiodic flows, and use their dual ξ 2 -system to uncover both hyperbolic and elliptic LCSs from a single computation.

Dissolver vessel bottom assembly

DOEpatents

Kilian, Douglas C.

1976-01-01

An improved bottom assembly is provided for a nuclear reactor fuel reprocessing dissolver vessel wherein fuel elements are dissolved as the initial step in recovering fissile material from spent fuel rods. A shock-absorbing crash plate with a convex upper surface is disposed at the bottom of the dissolver vessel so as to provide an annular space between the crash plate and the dissolver vessel wall. A sparging ring is disposed within the annular space to enable a fluid discharged from the sparging ring to agitate the solids which deposit on the bottom of the dissolver vessel and accumulate in the annular space. An inlet tangential to the annular space permits a fluid pumped into the annular space through the inlet to flush these solids from the dissolver vessel through tangential outlets oppositely facing the inlet. The sparging ring is protected against damage from the impact of fuel elements being charged to the dissolver vessel by making the crash plate of such a diameter that the width of the annular space between the crash plate and the vessel wall is less than the diameter of the fuel elements.

Fracture resistance of welded thick-walled high-pressure vessels in power plants. Report No. 2. Approach to evaluating static strength

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

Gorynin, I.V.; Filatov, V.M.; Ignatov, V.A.

1986-07-01

The authors examine data on the effect of defects on the fracture resistance of high-pressure vessels and their models obtained within the framework of the HSST program. Results of internal-pressure tests of two types of vessels with a wall thickness of 152 mm made from forgings of steels SA508 and SA533, as well as small vessels with a wall thickness of 11.5 and 23mm made of steel SA533 are shown. The authors state that testing thick-walled welded high-pressure vessels and thin-walled vessels with surface defects of different sizes has demonstrated that there are substantial static-strength reserves in structures designed bymore » existing domestic and foreign standards on the strength of power-plant equipment. A correction was proposed for the presently used method of calculating the resistance of highpressure vessels to brittle fracture that allows for the dimensions of the defects in relation to the type of vessel, the manufacturing technology, and the method of inspection.« less

A fundamental study of nucleate pool boiling under microgravity

NASA Technical Reports Server (NTRS)

Ervin, Jamie S.; Merte, Herman, Jr.

1991-01-01

An experimental study of incipient boiling in short-term microgravity and with a/g = +/- 1 for pool boiling was performed. Calibrated thin gold films sputtered on a smoothly polished quartz surface were used simultaneously for thermal resistance measurements and heating of the boiling surface. The gold films were used for both transient and quasi-steady heating surface temperature measurements. Two test vessels were constructed for precise measurement and control of fluid temperature and pressure: a laboratory pool boiling vessel for the a/g = +/- experiments and a pool boiling vessel designed for the 131 m free-fall in the NASA Lewis Research Center Microgravity Research Facility for the microgravity tests. Measurements included the heater surface temperature, the pressure near the heating surface, and the bulk liquid temperatures. High speed photography was used in the experiments. With high quality microgravity and the measured initial temperature of the quiescent test fluid, R113, the temperature distribution in the liquid at the moment of boiling inception resulting from an imposed step in heat flux is known with a certainty not possible previously. The types of boiling propagation across the large flat heating surface are categorized; the conditions necessary for their occurrence are described. Explosive boiling propagation with a striking pattern of small scale protuberances over the entire vapor mass periphery not observed previously at low heat flux levels is described. For the heater surface with a/g = -1, a step in the heater surface temperature of short duration was imposed. The resulting liquid temperature distribution at the moment of boiling inception was different from that obtained with a step in heat flux.

Crimp sealing of tubes flush with or below a fixed surface

DOEpatents

Fischer, J.E.; Walmsley, D.; Wapman, P.D.

1996-08-20

An apparatus for crimp sealing and severing tubes flush or below a fixed surface. Tube crimping below a fixed surface requires an asymmetric die and anvil configuration. The anvil must be flat so that, after crimping, it may be removed without deforming the crimped tubes. This asymmetric die and anvil is used when a ductile metal tube and valve assembly are attached to a pressure vessel which has a fixed surface around the base of the tube at the pressure vessel. A flat anvil is placed against the tube. Die guides are placed against the tube on a side opposite the anvil. A pinch-off die is inserted into the die guides against the tube. Adequate clearance for inserting the die and anvil around the tube is needed below the fixed surface. The anvil must be flat so that, after crimping, it may be removed without deforming the crimped tubes. 8 figs.

Crimp sealing of tubes flush with or below a fixed surface

DOEpatents

Fischer, Jon E.; Walmsley, Don; Wapman, P. Derek

1996-01-01

An apparatus for crimp sealing and severing tubes flush or below a fixed surface. Tube crimping below a fixed surface requires an asymmetric die and anvil configuration. The anvil must be flat so that, after crimping, it may be removed without deforming the crimped tubes. This asymmetric die and anvil is used when a ductile metal tube and valve assembly are attached to a pressure vessel which has a fixed surface around the base of the tube at the pressure vessel. A flat anvil is placed against the tube. Die guides are placed against the tube on a side opposite the anvil. A pinch-off die is inserted into the die guides against the tube. Adequate clearance for inserting the die and anvil around the tube is needed below the fixed surface. The anvil must be flat so that, after crimping, it may be removed without deforming the crimped tubes.

78 FR 61223 - Regulated Navigation Area; Southern Oahu Tsunami Vessel Evacuation, Honolulu, HI

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-03

... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 [Docket No. USCG-2012-0080] RIN 1625-AA00 Regulated Navigation Area; Southern Oahu Tsunami Vessel Evacuation, Honolulu, HI AGENCY: Coast... Pacific Ocean south of the southern shoreline of Oahu, HI, extending from the surface of the water to the...

78 FR 47282 - Takes of Marine Mammals Incidental to Specified Activities; Navy Research, Development, Test and...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-05

... Director. Post-mission surveys will be conducted from the surface vessel(s) and aircraft used for pre-test... post-test events. Systematic monitoring of the affected area for marine mammals will be conducted prior... Marine Mammals Incidental to Specified Activities; Navy Research, Development, Test and Evaluation...

Glassy-winged sharpshooter feeding does not cause air embolisms in xylem of well-watered plants.

USDA-ARS?s Scientific Manuscript database

Plant xylem vessels are under negative hydrostatic pressure (tension) as evapotranspiration of water from the leaf surface pulls the column of water in xylem upwards. When xylem fluid flux is under extreme tension, any puncture or breakage of the xylem vessel wall can cause formation of air embolis...

Analysis of On-Board Oxygen and Nitrogen Generation Systems for Surface Vessels.

DTIC Science & Technology

1983-06-01

and Pressure Vessel Code SAE AIR 822 Oxygen for General Aviation Aircraft SAE AIR 825 Oxygen for Aircrafts SAE AIR 1059 Transportation and Maintenance...OF THE TITLE MIL-T-27730 Threaded Components MIL-P-27401 A 40 Micron Filter For Nitrogen MIL-V-33650 Internal Straight Threads ASME Code VIII Boiler

75 FR 3395 - Taking and Importing Marine Mammals; U.S. Naval Surface Warfare Center Panama City Division...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-21

... al., 2003; 2004)). A detailed review of marine mammal reactions to ships and boats is available in... the following assessment regarding cetacean reactions to vessel traffic: Toothed whales: ``In summary, toothed whales sometimes show no avoidance reaction to vessels, or even approach them. However, avoidance...

46 CFR 170.125 - Operating information for a vessel engaged in lifting.

Code of Federal Regulations, 2010 CFR

2010-10-01

... is not counterballasted, stability information setting forth hook load limits corresponding to boom...) Instructions on the effect of the free surface of the counterballast water. (2) Instructions on the amounts of counterballast needed to compensate for hook load heeling moments. (3) If a vessel has fixed counterballast, a...

46 CFR 170.125 - Operating information for a vessel engaged in lifting.

Code of Federal Regulations, 2014 CFR

2014-10-01

... is not counterballasted, stability information setting forth hook load limits corresponding to boom...) Instructions on the effect of the free surface of the counterballast water. (2) Instructions on the amounts of counterballast needed to compensate for hook load heeling moments. (3) If a vessel has fixed counterballast, a...

46 CFR 170.125 - Operating information for a vessel engaged in lifting.

Code of Federal Regulations, 2013 CFR

2013-10-01

... is not counterballasted, stability information setting forth hook load limits corresponding to boom...) Instructions on the effect of the free surface of the counterballast water. (2) Instructions on the amounts of counterballast needed to compensate for hook load heeling moments. (3) If a vessel has fixed counterballast, a...

46 CFR 170.125 - Operating information for a vessel engaged in lifting.

Code of Federal Regulations, 2011 CFR

2011-10-01

... is not counterballasted, stability information setting forth hook load limits corresponding to boom...) Instructions on the effect of the free surface of the counterballast water. (2) Instructions on the amounts of counterballast needed to compensate for hook load heeling moments. (3) If a vessel has fixed counterballast, a...

46 CFR 170.125 - Operating information for a vessel engaged in lifting.

Code of Federal Regulations, 2012 CFR

2012-10-01

... is not counterballasted, stability information setting forth hook load limits corresponding to boom...) Instructions on the effect of the free surface of the counterballast water. (2) Instructions on the amounts of counterballast needed to compensate for hook load heeling moments. (3) If a vessel has fixed counterballast, a...

Bulge-Formed Cooling Channels In A Wall

NASA Technical Reports Server (NTRS)

Mcaninch, Michael D.; Holbrook, Richard L.; Lacount, Dale F.; Kawashige, Chester M.; Crapuchettes, John M.; Scala, James

1996-01-01

Vessels bounded by walls shaped as surfaces of revolution and contain integral cooling channels fabricated by improved method involving combination of welding and bulge forming. Devised to make rocket nozzles; also useful in fabrication of heat exchangers, stationary combustion chambers, and chemical-reactor vessels. Advantages include easier fabrication and greater flexibility of design.

Measurement of eddy-current distribution in the vacuum vessel of the Sino-UNIted Spherical Tokamak.

PubMed

Li, G; Tan, Y; Liu, Y Q

2015-08-01

Eddy currents have an important effect on tokamak plasma equilibrium and control of magneto hydrodynamic activity. The vacuum vessel of the Sino-UNIted Spherical Tokamak is separated into two hemispherical sections by a toroidal insulating barrier. Consequently, the characteristics of eddy currents are more complex than those found in a standard tokamak. Thus, it is necessary to measure and analyze the eddy-current distribution. In this study, we propose an experimental method for measuring the eddy-current distribution in a vacuum vessel. By placing a flexible printed circuit board with magnetic probes onto the external surface of the vacuum vessel to measure the magnetic field parallel to the surface and then subtracting the magnetic field generated by the vertical-field coils, the magnetic field due to the eddy current can be obtained, and its distribution can be determined. We successfully applied this method to the Sino-UNIted Spherical Tokamak, and thus, we obtained the eddy-current distribution despite the presence of the magnetic field generated by the external coils.

Mathematical study of the effects of different intrahepatic cooling on thermal ablation zones.

PubMed

Peng, Tingying; O'Neill, David; Payne, Stephen

2011-01-01

Thermal ablation of a tumour in the liver with Radio Frequency energy can be accomplished by using a probe inserted into the tissue under the guidance of medical imaging. The extent of ablation can be significantly affected by heat loss due to the high blood perfusion in the liver, especially when the tumour is located close to large vessels. A mathematical model is thus presented here to investigate the heat sinking effects of large vessels, combining a 3D two-equation coupled bio-heat model and a 1D model of convective heat transport across the blood vessel surface. The model simulation is able to recover the experimentally observed different intrahepatic cooling on thermal ablation zones: hepatic veins showed a focal indentation whereas portal veins showed broad flattening of the ablation zones. Moreover, this study also illustrates that this shape derivation can largely be attributed to the temperature variations between the microvascular branches of portal vein as compared with hepatic vein. In contrast, different amount of surface heat convection on the vessel wall between these two types of veins, however, has a minor effect.

Detection and characterisation of deep-sea benthopelagic animals from an autonomous underwater vehicle with a multibeam echosounder: A proof of concept and description of data-processing methods

NASA Astrophysics Data System (ADS)

Dunlop, Katherine M.; Jarvis, Toby; Benoit-Bird, Kelly J.; Waluk, Chad M.; Caress, David W.; Thomas, Hans; Smith, Kenneth L.

2018-04-01

Benthopelagic animals are an important component of the deep-sea ecosystem, yet are notoriously difficult to study. Multibeam echosounders (MBES) deployed on autonomous underwater vehicles (AUVs) represent a promising technology for monitoring this elusive fauna at relatively high spatial and temporal resolution. However, application of this remote-sensing technology to the study of small (relative to the sampling resolution), dispersed and mobile animals at depth does not come without significant challenges with respect to data collection, data processing and vessel avoidance. As a proof of concept, we used data from a downward-looking RESON SeaBat 7125 MBES mounted on a Dorado-class AUV to detect and characterise the location and movement of backscattering targets (which were likely to have been individual fish or squid) within 50 m of the seafloor at 800 m depth in Monterey Bay, California. The targets were detected and tracked, enabling their numerical density and movement to be characterised. The results revealed a consistent movement of targets downwards away from the AUV that we interpreted as an avoidance response. The large volume and complexity of the data presented a computational challenge, while reverberation and noise, spatial confounding and a marginal sampling resolution relative to the size of the targets caused difficulties for reliable and comprehensive target detection and tracking. Nevertheless, the results demonstrate that an AUV-mounted MBES has the potential to provide unique and detailed information on the in situ abundance, distribution, size and behaviour of both individual and aggregated deep-sea benthopelagic animals. We provide detailed data-processing information for those interested in working with MBES water-column data, and a critical appraisal of the data in the context of aquatic ecosystem research. We consider future directions for deep-sea water-column echosounding, and reinforce the importance of measures to mitigate vessel avoidance in studies of aquatic ecosystems.

50 CFR 216.244 - Mitigation.

Code of Federal Regulations, 2010 CFR

2010-10-01

... watch whose duties include observing the water surface around the vessel. (vii) All surface ships... lookout shall employ visual search procedures employing a scanning methodology in accordance with the Lookout Training Handbook (NAVEDTRA 12968-D). Surface lookouts should scan the water from the ship to the...

50 CFR 216.244 - Mitigation.

Code of Federal Regulations, 2011 CFR

2011-10-01

... watch whose duties include observing the water surface around the vessel. (vii) All surface ships... lookout shall employ visual search procedures employing a scanning methodology in accordance with the Lookout Training Handbook (NAVEDTRA 12968-D). Surface lookouts should scan the water from the ship to the...

Learning-based automated segmentation of the carotid artery vessel wall in dual-sequence MRI using subdivision surface fitting.

PubMed

Gao, Shan; van 't Klooster, Ronald; Kitslaar, Pieter H; Coolen, Bram F; van den Berg, Alexandra M; Smits, Loek P; Shahzad, Rahil; Shamonin, Denis P; de Koning, Patrick J H; Nederveen, Aart J; van der Geest, Rob J

2017-10-01

The quantification of vessel wall morphology and plaque burden requires vessel segmentation, which is generally performed by manual delineations. The purpose of our work is to develop and evaluate a new 3D model-based approach for carotid artery wall segmentation from dual-sequence MRI. The proposed method segments the lumen and outer wall surfaces including the bifurcation region by fitting a subdivision surface constructed hierarchical-tree model to the image data. In particular, a hybrid segmentation which combines deformable model fitting with boundary classification was applied to extract the lumen surface. The 3D model ensures the correct shape and topology of the carotid artery, while the boundary classification uses combined image information of 3D TOF-MRA and 3D BB-MRI to promote accurate delineation of the lumen boundaries. The proposed algorithm was validated on 25 subjects (48 arteries) including both healthy volunteers and atherosclerotic patients with 30% to 70% carotid stenosis. For both lumen and outer wall border detection, our result shows good agreement between manually and automatically determined contours, with contour-to-contour distance less than 1 pixel as well as Dice overlap greater than 0.87 at all different carotid artery sections. The presented 3D segmentation technique has demonstrated the capability of providing vessel wall delineation for 3D carotid MRI data with high accuracy and limited user interaction. This brings benefits to large-scale patient studies for assessing the effect of pharmacological treatment of atherosclerosis by reducing image analysis time and bias between human observers. © 2017 American Association of Physicists in Medicine.

Automatic lumen and outer wall segmentation of the carotid artery using deformable three-dimensional models in MR angiography and vessel wall images.

PubMed

van 't Klooster, Ronald; de Koning, Patrick J H; Dehnavi, Reza Alizadeh; Tamsma, Jouke T; de Roos, Albert; Reiber, Johan H C; van der Geest, Rob J

2012-01-01

To develop and validate an automated segmentation technique for the detection of the lumen and outer wall boundaries in MR vessel wall studies of the common carotid artery. A new segmentation method was developed using a three-dimensional (3D) deformable vessel model requiring only one single user interaction by combining 3D MR angiography (MRA) and 2D vessel wall images. This vessel model is a 3D cylindrical Non-Uniform Rational B-Spline (NURBS) surface which can be deformed to fit the underlying image data. Image data of 45 subjects was used to validate the method by comparing manual and automatic segmentations. Vessel wall thickness and volume measurements obtained by both methods were compared. Substantial agreement was observed between manual and automatic segmentation; over 85% of the vessel wall contours were segmented successfully. The interclass correlation was 0.690 for the vessel wall thickness and 0.793 for the vessel wall volume. Compared with manual image analysis, the automated method demonstrated improved interobserver agreement and inter-scan reproducibility. Additionally, the proposed automated image analysis approach was substantially faster. This new automated method can reduce analysis time and enhance reproducibility of the quantification of vessel wall dimensions in clinical studies. Copyright © 2011 Wiley Periodicals, Inc.

Development and testing of instrumentation for ship-based UAV measurements of ocean surface processes and the marine atmospheric boundary layer

NASA Astrophysics Data System (ADS)

Reineman, B. D.; Lenain, L.; Statom, N.; Melville, W. K.

2012-12-01

We have developed instrumentation packages for unmanned aerial vehicles (UAVs) to measure ocean surface processes along with momentum fluxes and latent, sensible, and radiative heat fluxes in the marine atmospheric boundary layer (MABL). The packages have been flown over land on BAE Manta C1s and over water on Boeing-Insitu ScanEagles. The low altitude required for accurate surface flux measurements (< 30 m) is below the typical safety limit of manned research aircraft; however, with advances in laser altimeters, small-aircraft flight control, and real-time kinematic differential GPS, low-altitude flight is now within the capability of small UAV platforms. Fast-response turbulence, hygrometer, and temperature probes permit turbulent flux measurements, and short- and long-wave radiometers allow the determination of net radiation, surface temperature, and albedo. Onboard laser altimetry and high-resolution visible and infrared video permit observations of surface waves and fine-scale (O(10) cm) ocean surface temperature structure. Flight tests of payloads aboard ScanEagle UAVs were conducted in April 2012 at the Naval Surface Warfare Center Dahlgren Division (Dahlgren, VA), where measurements of water vapor, heat, and momentum fluxes were made from low-altitude (31-m) UAV flights over water (Potomac River). ScanEagles are capable of ship-based launch and recovery, which can extend the reach of research vessels and enable scientific measurements out to ranges of O(10-100) km and altitudes up to 5 km. UAV-based atmospheric and surface observations can complement observations of surface and subsurface phenomena made from a research vessel and avoid the well-known problems of vessel interference in MABL measurements. We present a description of the instrumentation, summarize results from flight tests, and discuss potential applications of these UAVs for ship-based MABL studies.

Quantification and characterization of microbial biofilm community attached on the surface of fermentation vessels used in green table olive processing.

PubMed

Grounta, Athena; Doulgeraki, Agapi I; Panagou, Efstathios Z

2015-06-16

The aim of the present study was the quantification of biofilm formed on the surface of plastic vessels used in Spanish-style green olive fermentation and the characterization of the biofilm community by means of molecular fingerprinting. Fermentation vessels previously used in green olive processing were subjected to sampling at three different locations, two on the side and one on the bottom of the vessel. Prior to sampling, two cleaning treatments were applied to the containers, including (a) washing with hot tap water (60 °C) and household detergent (treatment A) and (b) washing with hot tap water, household detergent and bleach (treatment B). Population (expressed as log CFU/cm(2)) of total viable counts (TVC), lactic acid bacteria (LAB) and yeasts were enumerated by standard plating. Bulk cells (whole colonies) from agar plates were isolated for further characterization by PCR-DGGE. Results showed that regardless of the cleaning treatment no significant differences were observed between the different sampling locations in the vessel. The initial microbial population before cleaning ranged between 3.0-4.5 log CFU/cm(2) for LAB and 4.0-4.6 log CFU/cm(2) for yeasts. Cleaning treatments exhibited the highest effect on LAB that were recovered at 1.5 log CFU/cm(2) after treatment A and 0.2 log CFU/cm(2) after treatment B, whereas yeasts were recovered at approximately 1.9 log CFU/cm(2) even after treatment B. High diversity of yeasts was observed between the different treatments and sampling spots. The most abundant species recovered belonged to Candida genus, while Wickerhamomyces anomalus, Debaryomyces hansenii and Pichia guilliermondii were frequently detected. Among LAB, Lactobacillus pentosus was the most abundant species present on the abiotic surface of the vessels. Copyright © 2015 Elsevier B.V. All rights reserved.

The effects of marine traffic on the behaviour of Black Sea harbour porpoises (Phocoena phocoena relicta) within the Istanbul Strait, Turkey.

PubMed

Akkaya Bas, Aylin; Christiansen, Fredrik; Amaha Öztürk, Ayaka; Öztürk, Bayram; McIntosh, Caley

2017-01-01

Marine traffic is threatening cetaceans on a local and global scale. The Istanbul Strait is one of the busiest waterways, with up to 2,500 vessels present daily. This is the first study to assess the magnitude of short- and long-term behavioural changes of the endangered Black Sea harbour porpoises (Phocoena phocoena relicta) in the presence of marine vessels within the Istanbul Strait. Markov chains were used to investigate the effect of vessel presence on the transition probability between behavioural states (diving, surface-feeding and travelling), and to quantify the effect on the behavioural budget and bout length (duration of time spent in a given state) of porpoises. Further, the changes on swimming directions of porpoises in relation to vessel speed and distance was investigated using generalized linear models. In vessel presence, porpoises were less likely to remain in a given behavioural state and instead more likely to switch to another state. Because of this, the bout length of all three behavioural states decreased significantly in the presence of vessels. The vessel effect was sufficiently large to alter the behavioural budget, with surface-feeding decreasing significantly in the presence of vessels. However, when taking into account the proportion of time that porpoises were exposed to vessels (i.e. 50%), the measured effect size was not large enough to significantly alter the animals' cumulative (diurnal) behavioural budget. Additionally, vessel speed and distance had a significant effect on the probability of porpoises showing a response in their swimming directions. The southern and middle sections of the Istanbul Strait, which have the heaviest marine traffic pressure, had the lowest porpoise sightings throughout the year. Conversely, northern sections that were exposed to a lesser degree of marine traffic hold the highest porpoise sightings. The effect shown in this study in combination with increasing human impacts within the northern sections should be considered carefully and species-specific conservation actions, including establishment of protected areas, should be put in place to prevent the long-term consequences of marine traffic on the Black Sea harbour porpoise population.

The effects of marine traffic on the behaviour of Black Sea harbour porpoises (Phocoena phocoena relicta) within the Istanbul Strait, Turkey

PubMed Central

Christiansen, Fredrik; Amaha Öztürk, Ayaka; Öztürk, Bayram; McIntosh, Caley

2017-01-01

Marine traffic is threatening cetaceans on a local and global scale. The Istanbul Strait is one of the busiest waterways, with up to 2,500 vessels present daily. This is the first study to assess the magnitude of short- and long-term behavioural changes of the endangered Black Sea harbour porpoises (Phocoena phocoena relicta) in the presence of marine vessels within the Istanbul Strait. Markov chains were used to investigate the effect of vessel presence on the transition probability between behavioural states (diving, surface-feeding and travelling), and to quantify the effect on the behavioural budget and bout length (duration of time spent in a given state) of porpoises. Further, the changes on swimming directions of porpoises in relation to vessel speed and distance was investigated using generalized linear models. In vessel presence, porpoises were less likely to remain in a given behavioural state and instead more likely to switch to another state. Because of this, the bout length of all three behavioural states decreased significantly in the presence of vessels. The vessel effect was sufficiently large to alter the behavioural budget, with surface-feeding decreasing significantly in the presence of vessels. However, when taking into account the proportion of time that porpoises were exposed to vessels (i.e. 50%), the measured effect size was not large enough to significantly alter the animals’ cumulative (diurnal) behavioural budget. Additionally, vessel speed and distance had a significant effect on the probability of porpoises showing a response in their swimming directions. The southern and middle sections of the Istanbul Strait, which have the heaviest marine traffic pressure, had the lowest porpoise sightings throughout the year. Conversely, northern sections that were exposed to a lesser degree of marine traffic hold the highest porpoise sightings. The effect shown in this study in combination with increasing human impacts within the northern sections should be considered carefully and species-specific conservation actions, including establishment of protected areas, should be put in place to prevent the long-term consequences of marine traffic on the Black Sea harbour porpoise population. PMID:28296899

A PC-PU nanoparticle/PU/decellularized scaffold composite vascular patch: Synergistically optimized overall performance promotes endothelialization.

PubMed

Zhang, Jun; Liu, Cheng; Feng, Fuling; Wang, Dawei; Lu, Shuaishuai; Wei, Guo; Mo, Hong; Qiao, Tong

2017-12-01

Composite vascular patches have gained increasingly attention due to the limited availability of autologous patches (vascular graft materials made from the blood vessels of the same recipient), the lack of growth capability of nonautologous patches (vascular graft materials made from the blood vessels of a different donor) and the disadvantages of synthetic patches. In this study, we report a highly biocompatible phosphatidylcholine-polyurethane nanoparticle/polyurethane/decellularized scaffold composite vascular patch (PCVP). It was fabricated by a facile method - cosedimentation. Its in vitro blood and cell compatibility including hemolysis, plasma recalcification time, coagulation time, platelet adhesion and cytotoxicity was evaluated. The surface modified with phosphatidylcholine-polyurethane (PC-PU) nanoparticles exhibited the improved anticoagulation activity. The in vivo performance of the PCVP was investigated in a mouse model. The nanopatterned surface that resembled the concave-convex structure of the luminal surface of native blood vessels enhanced cell attachment, proliferation, migration and differentiation. The decellularized scaffold had the mechanical property similar to that of the targeted blood vessels, which could withstand in vivo dynamic blood pressure. The overall performance of the PCVP was synergistically optimized by each layer of the multilayer design. The patched artery remained patent and the formation of endothelial tissue - endothelialization was achieved 30days after the in vivo implantation in a mouse model. Copyright © 2017 Elsevier B.V. All rights reserved.

Refractory lining system for high wear area of high temperature reaction vessel

DOEpatents

Hubble, D.H.; Ulrich, K.H.

1998-04-21

A refractory-lined high temperature reaction vessel comprises a refractory ring lining constructed of refractory brick, a cooler, and a heat transfer medium disposed between the refractory ring lining and the cooler. The refractory brick comprises magnesia (MgO) and graphite. The heat transfer medium contacts the refractory brick and a cooling surface of the cooler, and is composed of a material that accommodates relative movement between the refractory brick and the cooler. The brick is manufactured such that the graphite has an orientation providing a high thermal conductivity in the lengthwise direction through the brick that is higher than the thermal conductivity in directions perpendicular to the lengthwise direction. The graphite preferably is flake graphite, in the range of about 10 to 20 wt %, and has a size distribution selected to provide maximum brick density. The reaction vessel may be used for performing a reaction process including the steps of forming a layer of slag on a melt in the vessel, the slag having a softening point temperature range, and forming a protective frozen layer of slag on the interior-facing surface of the refractory lining in at least a portion of a zone where the surface contacts the layer of slag, the protective frozen layer being maintained at or about the softening point of the slag. 10 figs.

Refractory lining system for high wear area of high temperature reaction vessel

DOEpatents

Hubble, D.H.; Ulrich, K.H.

1998-09-22

A refractory-lined high temperature reaction vessel comprises a refractory ring lining constructed of refractory brick, a cooler, and a heat transfer medium disposed between the refractory ring lining and the cooler. The refractory brick comprises magnesia (MgO) and graphite. The heat transfer medium contacts the refractory brick and a cooling surface of the cooler, and is composed of a material that accommodates relative movement between the refractory brick and the cooler. The brick is manufactured such that the graphite has an orientation providing a high thermal conductivity in the lengthwise direction through the brick that is higher than the thermal conductivity in directions perpendicular to the lengthwise direction. The graphite preferably is flake graphite, in the range of about 10 to 20 wt %, and has a size distribution selected to provide maximum brick density. The reaction vessel may be used for performing a reaction process including the steps of forming a layer of slag on a melt in the vessel, the slag having a softening point temperature range, and forming a protective frozen layer of slag on the interior-facing surface of the refractory lining in at least a portion of a zone where the surface contacts the layer of slag, the protective frozen layer being maintained at or about the softening point of the slag. 10 figs.

Upper Ocean Profiles Measurements with ASIP

NASA Astrophysics Data System (ADS)

Ward, B.; Callaghan, A. H.; Fristedt, T.; Vialard, J.; Cuypers, Y.; Weller, R. A.; Grosch, C. E.

2009-04-01

This presentation describes results from the Air-Sea Interaction Profiler (ASIP), an autonomous profiling instrument for upper ocean measurements. The measurements from ASIP are well suited to enhancing research on air-sea interfacial and near surface processes. Autonomous profiling is accomplished with a thruster, which submerges ASIP to a programmed depth. Once this depth is reached the positively buoyant instrument will ascend to the surface acquiring data. ASIP can profile from a maximum depth of 100 m to the surface, allowing both mixed layer and near-surface measurements to be conducted. The sensor payload on ASIP include microstructure sensors (two shear probes and a thermistor); a slow response accurate thermometer; a pair of conductivity sensors; pressure for a record of depth; PAR for measurements of light absorption in the water column. Other non-environmental sensors are acceleration, rate, and heading for determination of vehicle motion. Power is provided with rechargable lithium-ion batteries, supplying 1000 Whr, allowing approximately 300 profiles. ASIP also contains an iridium/GPS system, which allows realtime reporting of its position. ASIP was deployed extensively during the Cirene Indian Ocean campaign and our results focus on the data from the temperature, salinity, light, and shear sensors.

Dual-RiverSonde measurements of two-dimensional river flow patterns

USGS Publications Warehouse

Teague, C.C.; Barrick, D.E.; Lilleboe, P.M.; Cheng, R.T.; Stumpner, P.; Burau, J.R.

2008-01-01

Two-dimensional river flow patterns have been measured using a pair of RiverSondes in two experiments in the Sacramento-San Joaquin River Delta system of central California during April and October 2007. An experiment was conducted at Walnut Grove, California in order to explore the use of dual RiverSondes to measure flow patterns at a location which is important in the study of juvenile fish migration. The data available during the first experiment were limited by low wind, so a second experiment was conducted at Threemile Slough where wind conditions and surface turbulence historically have resulted in abundant data. Both experiments included ADCP near-surface velocity measurements from either manned or unmanned boats. Both experiments showed good comparisons between the RiverSonde and ADCP measurements. The flow conditions at both locations are dominated by tidal effects, with partial flow reversal at Walnut Grove and complete flow reversal at Threemile Slough. Both systems showed complex flow patterns during the flow reversals. Quantitative comparisons between the RiverSondes and an ADCP on a manned boat at Walnut Grove showed mean differences of 4.5 cm/s in the u (eastward) and 7.6 cm/s in the v (northward) components, and RMS differences of 14.7 cm/s in the u component and 21.0 cm/s in the v component. Quantitative comparisons between the RiverSondes and ADCPs on autonomous survey vessels at Threemile Slough showed mean differences of 0.007 cm/s in the u component and 0.5 cm/s in the v component, and RMS differences of 7.9 cm/s in the u component and 13.5 cm/s in the v component after obvious outliers were removed. ?? 2008 IEEE.

Device for inspecting vessel surfaces

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

Appel, D.K.

1995-12-12

A portable, remotely-controlled inspection crawler is described for use along the walls of tanks, vessels, piping and the like. The crawler can be configured to use a vacuum chamber for supporting itself on the inspected surface by suction or a plurality of magnetic wheels for moving the crawler along the inspected surface. The crawler is adapted to be equipped with an ultrasonic probe for mapping the structural integrity or other characteristics of the surface being inspected. Navigation of the crawler is achieved by triangulation techniques between a signal transmitter on the crawler and a pair of microphones attached to amore » fixed, remote location, such as the crawler`s deployment unit. The necessary communications are established between the crawler and computers external to the inspection environment for position control and storage and/or monitoring of data acquisition. 5 figs.« less

Gas-cooled nuclear reactor

DOEpatents

Peinado, Charles O.; Koutz, Stanley L.

1985-01-01

A gas-cooled nuclear reactor includes a central core located in the lower portion of a prestressed concrete reactor vessel. Primary coolant gas flows upward through the core and into four overlying heat-exchangers wherein stream is generated. During normal operation, the return flow of coolant is between the core and the vessel sidewall to a pair of motor-driven circulators located at about the bottom of the concrete pressure vessel. The circulators repressurize the gas coolant and return it back to the core through passageways in the underlying core structure. If during emergency conditions the primary circulators are no longer functioning, the decay heat is effectively removed from the core by means of natural convection circulation. The hot gas rising through the core exits the top of the shroud of the heat-exchangers and flows radially outward to the sidewall of the concrete pressure vessel. A metal liner covers the entire inside concrete surfaces of the concrete pressure vessel, and cooling tubes are welded to the exterior or concrete side of the metal liner. The gas coolant is in direct contact with the interior surface of the metal liner and transfers its heat through the metal liner to the liquid coolant flowing through the cooling tubes. The cooler gas is more dense and creates a downward convection flow in the region between the core and the sidewall until it reaches the bottom of the concrete pressure vessel when it flows radially inward and up into the core for another pass. Water is forced to flow through the cooling tubes to absorb heat from the core at a sufficient rate to remove enough of the decay heat created in the core to prevent overheating of the core or the vessel.

Evacuated optical structure comprising optical bench mounted to sidewall of vacuum chamber in a manner which inhibits deflection and rotation of the optical bench

DOEpatents

Bowers, Joel M.

1994-01-01

An improved evacuated optical structure is disclosed comprising an optical bench mounted in a vacuum vessel in a manner which inhibits transmission of movement of the vacuum vessel to the optical bench, yet provides a compact and economical structure. The vacuum vessel is mounted, through a sidewall thereof, to a support wall at four symmetrically positioned and spaced apart areas, each of which comprises a symmetrically positioned group of mounting structures passing through the sidewall of the vacuum vessel. The optical bench is pivotally secured to the vacuum vessel by four symmetrically spaced apart bolts and spherical bearings, each of which is centrally positioned within one of the four symmetrically positioned groups of vacuum vessel mounting structures. Cover plates and o-ring seals are further provided to seal the vacuum vessel mounting structures from the interior of the vacuum vessel, and venting bores are provided to vent trapped gases in the bores used to secure the cover plates and o-rings to the vacuum vessel. Provision for detecting leaks in the mounting structures from the rear surface of the vacuum vessel sidewall facing the support wall are also provided. Deflection to the optical bench within the vacuum vessel is further minimized by tuning the structure for a resonant frequency of at least 100 Hertz.

Evacuated optical structure comprising optical bench mounted to sidewall of vacuum chamber in a manner which inhibits deflection and rotation of the optical bench

DOEpatents

Bowers, J.M.

1994-04-19

An improved evacuated optical structure is disclosed comprising an optical bench mounted in a vacuum vessel in a manner which inhibits transmission of movement of the vacuum vessel to the optical bench, yet provides a compact and economical structure. The vacuum vessel is mounted, through a sidewall thereof, to a support wall at four symmetrically positioned and spaced apart areas, each of which comprises a symmetrically positioned group of mounting structures passing through the sidewall of the vacuum vessel. The optical bench is pivotally secured to the vacuum vessel by four symmetrically spaced apart bolts and spherical bearings, each of which is centrally positioned within one of the four symmetrically positioned groups of vacuum vessel mounting structures. Cover plates and o-ring seals are further provided to seal the vacuum vessel mounting structures from the interior of the vacuum vessel, and venting bores are provided to vent trapped gases in the bores used to secure the cover plates and o-rings to the vacuum vessel. Provision for detecting leaks in the mounting structures from the rear surface of the vacuum vessel sidewall facing the support wall are also provided. Deflection to the optical bench within the vacuum vessel is further minimized by tuning the structure for a resonant frequency of at least 100 Hertz. 10 figures.

Gulf of Mexico Monitoring Via The Remotely Controlled CMR SailBuoy

NASA Astrophysics Data System (ADS)

Wienders, N.; Hole, L. R.; Peddie, D.

2013-12-01

The CMR SailBuoy is an unmanned ocean vessel capable of traveling the oceans for extended periods of time. It navigates the oceans autonomously - transmitting data at regular intervals using the Iridium network for two way communication. The SailBuoy can be used for a wide variety of ocean applications from measuring ocean and atmospheric parameters to tracking oil spills or acting as a communication relay station for subsea instrumentation. As part of the Deep-C project(Deep Sea to Coast Connectivity in the Eastern Gulf of Mexico), a two month campaign was carried out from March to May 2013 with the purpose of collecting sea surface data (temperature, salinity and oxygen) during the spring bloom. The campaign was unique in that the SailBouy was remotely controlled from Norway after being deployed from the RV Apalachee. The SailBuoy was deployed approximately 11 nautical miles (nm) south of Cape San Blas. During its mission she sailed approximately 840nm on a cruise track across the Gulf coast, from the Florida Panhandle to Louisiana. The SailBuoy project is part of Deep-C's physical oceanography research which seeks to, among other things, understand how particles and dissolved substances (such as oil) travel from the deep sea to the Louisiana, Mississippi, Alabama and Florida shorelines. This involves cross-shelf transport and upwelling mechanisms, which the SailBuoy is capable of measuring. An other focus was the sampling of the Mississippi river plume, which has been shown to influence the distribution of particles, oil, dissolved substances in the water, at least at the surface level. Sea surface salinity measurement via satellite do not provide, at the moment, sufficient resolution and accuracy and instead, the SailBuoy seems to be a very convenient instrument to track river plumes. In this presentation we describe the collected data and include comparisons with high resolution ocean model outputs. We also present further plans for SailBuoy campaigns.

Natural hydrocarbon seeps observation with underwater gliders and UV fluorescence sensor

NASA Astrophysics Data System (ADS)

Rochet, V.

2016-02-01

Hydrocarbons may leak to the near-surface from subsurface accumulations, from mature source rock, or by buoyancy along major cross-strata routes. The presence of migrating near-surface hydrocarbons can provide strong evidence for the presence of a working petroleum system, as well as valuable information on source, maturity, and migration pathways. Detection and characterization of hydrocarbons in the water column may then help to de-risk hydrocarbon plays at a very preliminary stage of an exploration program. In order to detect hydrocarbons in the water column, an underwater glider survey was conducted in an offshore frontier area. Driven by buoyancy variation, underwater gliders enable collecting data autonomously along the water column for weeks to months. Underwater gliders are regularly piloted from shore by satellite telemetry and do not require a surface supervising vessel resulting in substantial operational costs savings. The data compiled, over 700m depth of the water column, included temperature, salinity, pressure, dissolved oxygen and hydrocarbon components (phenanthrene and naphthalene) measured by "MINIFLUO" sensors to particularly target representative crude oil compounds Two gliders were deployed at sea, one from coast in shallow water and the other one offshore on the survey area. Both accurately squared the survey area following pre-defined lines and cross lines. Data files were transmitted by satellite telemetry in near real time during the performance of the mission for real time observations and appropriate re-positioning of the gliders. Using rechargeable underwater gliders increased reliability reducing the risk of leakage and associated logistics during operation at sea. Despite strong evidences of seabed seepages such as pockmarks, faults, etc, over the area of interest, no hydrocarbon indices were detected in the water column, which was confirmed later by seabed sample analysis. The use of glider platforms for hydrocarbon detection has been demonstrated, and they can nowadays be utilized as a proven and efficient technology for hydrocarbon exploration purposes beyond their classical oceanology uses.

An Astronaut Assistant Rover for Martian Surface Exploration

NASA Astrophysics Data System (ADS)

1999-01-01

Lunar exploration, recent field tests, and even on-orbit operations suggest the need for a robotic assistant for an astronaut during extravehicular activity (EVA) tasks. The focus of this paper is the design of a 300-kg, 2 cubic meter, semi-autonomous robotic rover to assist astronauts during Mars surface exploration. General uses of this rover include remote teleoperated control, local EVA astronaut control, and autonomous control. Rover size, speed, sample capacity, scientific payload and dexterous fidelity were based on known Martian environmental parameters,- established National Aeronautics and Space Administration (NASA) standards, the NASA Mars Exploration Reference Mission, and lessons learned from lunar and on-orbit sorties. An assumed protocol of a geological, two astronaut EVA performed during daylight hours with a maximum duration of tour hour dictated the following design requirements: (1) autonomously follow the EVA team over astronaut traversable Martian terrain for four hours; (2) retrieve, catalog, and carry 12 kg of samples; (3) carry tools and minimal in-field scientific equipment; (4) provide contingency life support; (5) compile and store a detailed map of surrounding terrain and estimate current position with respect to base camp; (6) provide supplemental communications systems; and (7) carry and support the use of a 7 degree - of- freedom dexterous manipulator.

A Hybrid FPGA/Tilera Compute Element for Autonomous Hazard Detection and Navigation

NASA Technical Reports Server (NTRS)

Villalpando, Carlos Y.; Werner, Robert A.; Carson, John M., III; Khanoyan, Garen; Stern, Ryan A.; Trawny, Nikolas

2013-01-01

To increase safety for future missions landing on other planetary or lunar bodies, the Autonomous Landing and Hazard Avoidance Technology (ALHAT) program is developing an integrated sensor for autonomous surface analysis and hazard determination. The ALHAT Hazard Detection System (HDS) consists of a Flash LIDAR for measuring the topography of the landing site, a gimbal to scan across the terrain, and an Inertial Measurement Unit (IMU), along with terrain analysis algorithms to identify the landing site and the local hazards. An FPGA and Manycore processor system was developed to interface all the devices in the HDS, to provide high-resolution timing to accurately measure system state, and to run the surface analysis algorithms quickly and efficiently. In this paper, we will describe how we integrated COTS components such as an FPGA evaluation board, a TILExpress64, and multi-threaded/multi-core aware software to build the HDS Compute Element (HDSCE). The ALHAT program is also working with the NASA Morpheus Project and has integrated the HDS as a sensor on the Morpheus Lander. This paper will also describe how the HDS is integrated with the Morpheus lander and the results of the initial test flights with the HDS installed. We will also describe future improvements to the HDSCE.

A hybrid FPGA/Tilera compute element for autonomous hazard detection and navigation

NASA Astrophysics Data System (ADS)

Villalpando, C. Y.; Werner, R. A.; Carson, J. M.; Khanoyan, G.; Stern, R. A.; Trawny, N.

To increase safety for future missions landing on other planetary or lunar bodies, the Autonomous Landing and Hazard Avoidance Technology (ALHAT) program is developing an integrated sensor for autonomous surface analysis and hazard determination. The ALHAT Hazard Detection System (HDS) consists of a Flash LIDAR for measuring the topography of the landing site, a gimbal to scan across the terrain, and an Inertial Measurement Unit (IMU), along with terrain analysis algorithms to identify the landing site and the local hazards. An FPGA and Manycore processor system was developed to interface all the devices in the HDS, to provide high-resolution timing to accurately measure system state, and to run the surface analysis algorithms quickly and efficiently. In this paper, we will describe how we integrated COTS components such as an FPGA evaluation board, a TILExpress64, and multi-threaded/multi-core aware software to build the HDS Compute Element (HDSCE). The ALHAT program is also working with the NASA Morpheus Project and has integrated the HDS as a sensor on the Morpheus Lander. This paper will also describe how the HDS is integrated with the Morpheus lander and the results of the initial test flights with the HDS installed. We will also describe future improvements to the HDSCE.

Autonomous portable solar ultraviolet spectroradiometer (APSUS) - a new CCD spectrometer system for localized, real-time solar ultraviolet (280-400 nm) radiation measurement.

PubMed

Hooke, Rebecca; Pearson, Andy; O'Hagan, John

2014-01-01

Terrestrial solar ultraviolet (UV) radiation has significant implications for human health and increasing levels are a key concern regarding the impact of climate change. Monitoring solar UV radiation at the earth's surface is therefore of increasing importance. A new prototype portable CCD (charge-coupled device) spectrometer-based system has been developed that monitors UV radiation (280-400 nm) levels at the earth's surface. It has the ability to deliver this information to the public in real time. Since the instrument can operate autonomously, it is called the Autonomous Portable Solar Ultraviolet Spectroradiometer (APSUS). This instrument incorporates an Ocean Optics QE65000 spectrometer which is contained within a robust environmental housing. The APSUS system can gather reliable solar UV spectral data from approximately April to October inclusive (depending on ambient temperature) in the UK. In this study the new APSUS unit and APSUS system are presented. Example solar UV spectra and diurnal UV Index values as measured by the APSUS system in London and Weymouth in the UK in summer 2012 are shown. © 2014 Crown copyright. Photochemistry and Photobiology © 2014 The American Society of Photobiology. This article is published with the permission of the Controller of HMSO and the Queen's Printer for Scotland and Public Health England.

Damage Detection and Verification System (DDVS) for In-Situ Health Monitoring

NASA Technical Reports Server (NTRS)

Williams, Martha K.; Lewis, Mark; Szafran, J.; Shelton, C.; Ludwig, L.; Gibson, T.; Lane, J.; Trautwein, T.

2015-01-01

Project presentation for Game Changing Program Smart Book Release. Detection and Verification System (DDVS) expands the Flat Surface Damage Detection System (FSDDS) sensory panels damage detection capabilities and includes an autonomous inspection capability utilizing cameras and dynamic computer vision algorithms to verify system health. Objectives of this formulation task are to establish the concept of operations, formulate the system requirements for a potential ISS flight experiment, and develop a preliminary design of an autonomous inspection capability system that will be demonstrated as a proof-of-concept ground based damage detection and inspection system.

A photovoltaic-driven and energy-autonomous CMOS implantable sensor.

PubMed

Ayazian, Sahar; Akhavan, Vahid A; Soenen, Eric; Hassibi, Arjang

2012-08-01

An energy-autonomous, photovoltaic (PV)-driven and MRI-compatible CMOS implantable sensor is presented. On-chip P+/N-well diode arrays are used as CMOS-compatible PV cells to harvest μW's of power from the light that penetrates into the tissue. In this 2.5 mm × 2.5 mm sub-μW integrated system, the in-vivo physiological signals are first measured by using a subthreshold ring oscillator-based sensor, the acquired data is then modulated into a frequency-shift keying (FSK) signal, and finally transmitted neuromorphically to the skin surface by using a pair of polarized electrodes.

British Geological Survey remotely operated sea bed rockdrills and vibrocorers: new advances to meet the needs of the scientific community.

NASA Astrophysics Data System (ADS)

Stewart, H. A.; Stevenson, A.; Wilson, M.; Pheasant, I.

2014-12-01

The British Geological Survey (BGS) have developed a number of coring and drilling systems for use in science projects in the UK and internationally. These include 3m and 6m vibrocoring systems; a 5m combined rockdrill and vibrocorer system; an oriented drill designed specifically to recover samples for use in palaeomagnetic studies; and a 55m rockdrill (RockDrill2). Recently, BGS have developed an autonomous, battery-operated vibrocoring system compatible with both the 3m and 6m vibrocorers, which can be used in water depths up to 6000m. Use of a battery system negates the use of an umbilical power cable to operate the vibrocorer, which instead can be deployed using the vessels A-frame and winch. The autonomous battery system comprises six 48V 19Ah batteries connected in series to give a 288V power source, a microprocessor and real-time clock. Data from the sensors are recorded with a time-stamp, giving diagnostic information that can be downloaded once the system is returned to the deck. The vibrocorer is operated via a pre-set program which is set up before deployment.The new system not only allows vibrocoring in greater water depths, but can also be used on smaller vessels where deck space is limited as a separate winch and umbilical is not required. The autonomous system was used for the first time in June 2014 on-board the RV Belgica to acquire samples from 20 sites in the Dangeard and Explorer canyon heads, off the southwest of England in 430m water depth.Another development is the BGS 55m rockdrill (RockDrill2), a remotely operated sampling system capable of coring up to 55m below sea floor in water depths up to 4000m. The rockdrill can be operated via its own launch and recovery system and can be outfitted with additional sensors such as gas flow meters, which have been designed by the BGS for assessing volume of gas hydrate, and down-hole logging tools. The 55m rockdrill has recently been used to sample hydrate-entrained sediments in the Sea of Japan. The maximum coring depth achieved was 32m below sea floor and the system can operate for more than 50 hours on a single deployment. The BGS system will be used in conjunction with the Bremen University (MARUM) MeBo sea-floor rockdrill on future International Ocean Discovery Program (IODP) expeditions.

Methods for producing films using supercritical fluid

DOEpatents

Yonker, Clement R.; Fulton, John L.

2004-06-15

A method for forming a continuous film on a substrate surface that involves depositing particles onto a substrate surface and contacting the particle-deposited substrate surface with a supercritical fluid under conditions sufficient for forming a continuous film from the deposited particles. The particles may have a mean particle size of less 1 micron. The method may be performed by providing a pressure vessel that can contain a compressible fluid. A particle-deposited substrate is provided in the pressure vessel and the compressible fluid is maintained at a supercritical or sub-critical state sufficient for forming a film from the deposited particles. The T.sub.g of particles may be reduced by subjecting the particles to the methods detailed in the present disclosure.

Enhanced pearl-chain formation by electrokinetic interaction with the bottom surface of vessel.

PubMed

Nishimura, Satoshi; Matsumura, Hideo; Kosuge, Katsunori; Yamaguchi, Tomohiko

2007-08-14

Counterions in an electric double layer (EDL) around a colloidal particle accumulate on one side of the EDL and are deficient on the other side under an electric field, resulting in an imbalance of ionic concentration in the EDL, that is to say, the ionic polarization of EDL. It is well known that the ionic polarization of EDL induces electric dipole moments whereby the alignments of colloidal particles (e.g., pearl chains) are formed under alternating electric fields. In this study, we focus on the effect of the frequency of applied electric fields (100 Hz-1 kHz) on the alignment of silica particles settling at the bottom of a silica glass vessel. In digital imaging analyses for pearl chains of silica particles, it is confirmed that surface distances between two neighboring particles decrease but the number of particles in a pearl chain increases as the frequency of the applied electric field is lowered from 1 kHz to 100 Hz. More interestingly, electrical conductance measurements suggest that the induced ionic polarization of EDL around silica particles at the bottom of the silica vessel is enhanced as the frequency is lowered from 1 kHz to 100 Hz, whereas the ionic polarization around isolated silica particles in uniform dispersions is alleviated by the relaxation of ionic concentration in the EDL as a result of the diffusion of counterions. This curious phenomenon can be explained by considering that the ionic polarization of EDL of silica particles at the bottom of a vessel is affected by the electro-osmosis of the silica surface at the bottom of the vessel.

Segmentation of the heart and major vascular structures in cardiovascular CT images

NASA Astrophysics Data System (ADS)

Peters, J.; Ecabert, O.; Lorenz, C.; von Berg, J.; Walker, M. J.; Ivanc, T. B.; Vembar, M.; Olszewski, M. E.; Weese, J.

2008-03-01

Segmentation of organs in medical images can be successfully performed with shape-constrained deformable models. A surface mesh is attracted to detected image boundaries by an external energy, while an internal energy keeps the mesh similar to expected shapes. Complex organs like the heart with its four chambers can be automatically segmented using a suitable shape variablility model based on piecewise affine degrees of freedom. In this paper, we extend the approach to also segment highly variable vascular structures. We introduce a dedicated framework to adapt an extended mesh model to freely bending vessels. This is achieved by subdividing each vessel into (short) tube-shaped segments ("tubelets"). These are assigned to individual similarity transformations for local orientation and scaling. Proper adaptation is achieved by progressively adapting distal vessel parts to the image only after proximal neighbor tubelets have already converged. In addition, each newly activated tubelet inherits the local orientation and scale of the preceeding one. To arrive at a joint segmentation of chambers and vasculature, we extended a previous model comprising endocardial surfaces of the four chambers, the left ventricular epicardium, and a pulmonary artery trunk. Newly added are the aorta (ascending and descending plus arch), superior and inferior vena cava, coronary sinus, and four pulmonary veins. These vessels are organized as stacks of triangulated rings. This mesh configuration is most suitable to define tubelet segments. On 36 CT data sets reconstructed at several cardiac phases from 17 patients, segmentation accuracies of 0.61-0.80mm are obtained for the cardiac chambers. For the visible parts of the newly added great vessels, surface accuracies of 0.47-1.17mm are obtained (larger errors are asscociated with faintly contrasted venous structures).

Autonomous Laser-Powered Vehicle

NASA Technical Reports Server (NTRS)

Stone, William C. (Inventor); Hogan, Bartholomew P. (Inventor)

2017-01-01

An autonomous laser-powered vehicle designed to autonomously penetrate through ice caps of substantial (e.g., kilometers) thickness by melting a path ahead of the vehicle as it descends. A high powered laser beam is transmitted to the vehicle via an onboard bare fiber spooler. After the beam enters through the dispersion optics, the beam expands into a cavity. A radiation shield limits backscatter radiation from heating the optics. The expanded beam enters the heat exchanger and is reflected by a dispersion mirror. Forward-facing beveled circular grooves absorb the reflected radiant energy preventing the energy from being reflected back towards the optics. Microchannels along the inner circumference of the beam dump heat exchanger maximize heat transfer. Sufficient amount of fiber is wound on the fiber spooler to permit not only a descent but also to permit a sample return mission by inverting the vehicle and melting its way back to the surface.

Unsupervised feature learning for autonomous rock image classification

NASA Astrophysics Data System (ADS)

Shu, Lei; McIsaac, Kenneth; Osinski, Gordon R.; Francis, Raymond

2017-09-01

Autonomous rock image classification can enhance the capability of robots for geological detection and enlarge the scientific returns, both in investigation on Earth and planetary surface exploration on Mars. Since rock textural images are usually inhomogeneous and manually hand-crafting features is not always reliable, we propose an unsupervised feature learning method to autonomously learn the feature representation for rock images. In our tests, rock image classification using the learned features shows that the learned features can outperform manually selected features. Self-taught learning is also proposed to learn the feature representation from a large database of unlabelled rock images of mixed class. The learned features can then be used repeatedly for classification of any subclass. This takes advantage of the large dataset of unlabelled rock images and learns a general feature representation for many kinds of rocks. We show experimental results supporting the feasibility of self-taught learning on rock images.

Autonomous Exploration for Gathering Increased Science

NASA Technical Reports Server (NTRS)

Bornstein, Benjamin J.; Castano, Rebecca; Estlin, Tara A.; Gaines, Daniel M.; Anderson, Robert C.; Thompson, David R.; DeGranville, Charles K.; Chien, Steve A.; Tang, Benyang; Burl, Michael C.;

Analysis of the Effect of Environmental Conditions in Conducting Amphibious Assaults Using a Ship Simulator/Vessel-Response Model Proof-of-Concept Study

DTIC Science & Technology

2017-05-01

Analyzing these factors enables a planner to develop an axis-of-advance that a vessel can easily maintain, as well as to reduce the travel time from...operational risk by testing the feasibility of the navigability of an area; 2) determining the capacity and timing of that operation; 3) defining the...conditions at this location dictate that only a narrow window of time is available for conducting surface ship-to- shore operations. The vessel

CRAFT: Collaborative Rover and Astronauts Future Technology

NASA Astrophysics Data System (ADS)

Da-Poian, V. D. P.; Koryanov, V. V. K.

2018-02-01

Our project is focusing on the relationship between astronauts and rovers to best work together during surface explorations. Robots will help and assist astronauts, and will also work autonomously. Our project is to develop this type of rover.

Characterizing the Lunar Particulate Atmosphere with the Autonomous Lunar Dust Observer (ALDO)

NASA Astrophysics Data System (ADS)

Grund, C. J.; Colwell, J. A.

2008-07-01

Photoelectric effects and solar wind charge the lunar surface, levitating particles. ALDO maps suspended dust in 3D using lidar. Phenomenology and instrument modeling, applications, projected performance and concepts of operation are discussed.

Autonomous navigation using lunar beacons

NASA Technical Reports Server (NTRS)

Khatib, A. R.; Ellis, J.; French, J.; Null, G.; Yunck, T.; Wu, S.

1983-01-01

The concept of using lunar beacon signal transmission for on-board navigation for earth satellites and near-earth spacecraft is described. The system would require powerful transmitters on the earth-side of the moon's surface and black box receivers with antennae and microprocessors placed on board spacecraft for autonomous navigation. Spacecraft navigation requires three position and three velocity elements to establish location coordinates. Two beacons could be soft-landed on the lunar surface at the limits of allowable separation and each would transmit a wide-beam signal with cones reaching GEO heights and be strong enough to be received by small antennae in near-earth orbit. The black box processor would perform on-board computation with one-way Doppler/range data and dynamical models. Alternatively, GEO satellites such as the GPS or TDRSS spacecraft can be used with interferometric techniques to provide decimeter-level accuracy for aircraft navigation.

Fracture and crack growth resistance studies of 304 stainless steel weldments relating to retesting of cryogenic vessels

NASA Technical Reports Server (NTRS)

Hall, L. R.; Finger, R. W.

1972-01-01

Fracture and crack growth resistance characteristics of 304 stainless steel alloy weldments as relating to retesting of cryogenic vessels were examined. Welding procedures were typical of those used in full scale vessel fabrication. Fracture resistance survey tests were conducted in room temperature air, liquid nitrogen and liquid hydrogen. In air, both surface-flawed and center-cracked panels containing cracks in weld metal, fusion line, heat-affected zone, or parent metal were tested. In liquid nitrogen and liquid hydrogen, tests were conducted using center-cracked panels containing weld centerline cracks. Load-unload, sustained load, and cyclic load tests were performed in air or hydrogen gas, liquid nitrogen, and liquid hydrogen using surface-flawed specimens containing weld centerline cracks. Results were used to evaluate the effectiveness of periodic proof overloads in assuring safe and reliable operation of over-the-road cryogenic dewars.

Multisample conversion of water to hydrogen by zinc for stable isotope determination

USGS Publications Warehouse

Kendall, C.; Coplen, T.B.

1985-01-01

Two techniques for the conversion of water to hydrogen for stable isotope ratio determination have been developed that are especially suited for automated multisample analysis. Both procedures involve reaction of zinc shot with a water sample at 450 ??C. in one method designed for water samples in bottles, the water is put in capillaries and is reduced by zinc in reaction vessels; overall savings in sample preparation labor of 75% have been realized over the standard uranium reduction technique. The second technique is for waters evolved under vacuum and is a sealed-tube method employing 9 mm o.d. quartz tubing. Problems inherent with zinc reduction include surface inhomogeneity of the zinc and exchange of hydrogen both with the zinc and with the glass walls of the vessels. For best results, water/zinc and water/glass surface area ratios of vessels should be kept as large as possible.

Identification of Important Iranian Hardwoods by Morphological Properties of Vessel Elements (Maceration process)

Treesearch

Vahidreza Safdari; Margaret S. Devall

2011-01-01

For the identification of small to large wood samples and various types of composites that may not provide enough of all surfaces necessary to reveal diagnostic characteristics, such as sawdust, decayed wood fragments, archeological wood, and even large wood samples, morphological and anatomical characteristics of vessels are very useful. In this research,...

46 CFR 178.340 - Stability standards for pontoon vessels on protected waters.

Code of Federal Regulations, 2011 CFR

2011-10-01

... = 2.0 feet (0.61 meters); Mw = Wind heeling moment in foot-pounds (kilogram-meters) P = Wind pressure of 7.5 pounds/square foot (36.6 kilograms/square meter); A = Area, in square feet (square meters), of the projected lateral surface of the vessel above the waterline (including each projected area of the...

46 CFR 178.340 - Stability standards for pontoon vessels on protected waters.

Code of Federal Regulations, 2014 CFR

2014-10-01

... = 2.0 feet (0.61 meters); Mw = Wind heeling moment in foot-pounds (kilogram-meters) P = Wind pressure of 7.5 pounds/square foot (36.6 kilograms/square meter); A = Area, in square feet (square meters), of the projected lateral surface of the vessel above the waterline (including each projected area of the...

46 CFR 178.340 - Stability standards for pontoon vessels on protected waters.

Code of Federal Regulations, 2012 CFR

2012-10-01

... = 2.0 feet (0.61 meters); Mw = Wind heeling moment in foot-pounds (kilogram-meters) P = Wind pressure of 7.5 pounds/square foot (36.6 kilograms/square meter); A = Area, in square feet (square meters), of the projected lateral surface of the vessel above the waterline (including each projected area of the...

46 CFR 178.340 - Stability standards for pontoon vessels on protected waters.

Code of Federal Regulations, 2013 CFR

2013-10-01

... = 2.0 feet (0.61 meters); Mw = Wind heeling moment in foot-pounds (kilogram-meters) P = Wind pressure of 7.5 pounds/square foot (36.6 kilograms/square meter); A = Area, in square feet (square meters), of the projected lateral surface of the vessel above the waterline (including each projected area of the...

30 CFR 56.13001 - General requirements for boilers and pressure vessels.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false General requirements for boilers and pressure vessels. 56.13001 Section 56.13001 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers §...

30 CFR 56.13001 - General requirements for boilers and pressure vessels.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false General requirements for boilers and pressure vessels. 56.13001 Section 56.13001 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers §...

30 CFR 56.13001 - General requirements for boilers and pressure vessels.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false General requirements for boilers and pressure vessels. 56.13001 Section 56.13001 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers §...

30 CFR 56.13001 - General requirements for boilers and pressure vessels.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false General requirements for boilers and pressure vessels. 56.13001 Section 56.13001 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers §...

30 CFR 56.13001 - General requirements for boilers and pressure vessels.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false General requirements for boilers and pressure vessels. 56.13001 Section 56.13001 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers §...

46 CFR 28.550 - Icing.

Code of Federal Regulations, 2010 CFR

2010-10-01

... ice on each surface above the waterline of a vessel which operates north of 66°30′ North latitude or... (d) of this section, the weight of assumed ice on a vessel that operates north of 42° North but south... height of the center of gravity of the accumulated ice should be calculated according to the position of...

46 CFR 28.550 - Icing.

Code of Federal Regulations, 2014 CFR

2014-10-01

... ice on each surface above the waterline of a vessel which operates north of 66°30′ North latitude or... (d) of this section, the weight of assumed ice on a vessel that operates north of 42° North but south... height of the center of gravity of the accumulated ice should be calculated according to the position of...

46 CFR 28.550 - Icing.

Code of Federal Regulations, 2013 CFR

2013-10-01

... ice on each surface above the waterline of a vessel which operates north of 66°30′ North latitude or... (d) of this section, the weight of assumed ice on a vessel that operates north of 42° North but south... height of the center of gravity of the accumulated ice should be calculated according to the position of...

46 CFR 28.550 - Icing.

Code of Federal Regulations, 2011 CFR

2011-10-01

... ice on each surface above the waterline of a vessel which operates north of 66°30′ North latitude or... (d) of this section, the weight of assumed ice on a vessel that operates north of 42° North but south... height of the center of gravity of the accumulated ice should be calculated according to the position of...

Heat treating of manufactured components

DOEpatents

Ripley, Edward B [Knoxville, TN

2012-05-22

An apparatus for heat treating manufactured components using microwave energy and microwave susceptor material is disclosed. The system typically includes an insulating vessel placed within a microwave applicator chamber. A moderating material is positioned inside the insulating vessel so that a substantial portion of the exterior surface of each component for heat treating is in contact with the moderating material.

Could the heat sink effect of blood flow inside large vessels protect the vessel wall from thermal damage during RF-assisted surgical resection?

PubMed

González-Suárez, Ana; Trujillo, Macarena; Burdío, Fernando; Andaluz, Anna; Berjano, Enrique

2014-08-01

To assess by means of computer simulations whether the heat sink effect inside a large vessel (portal vein) could protect the vessel wall from thermal damage close to an internally cooled electrode during radiofrequency (RF)-assisted resection. First,in vivo experiments were conducted to validate the computational model by comparing the experimental and computational thermal lesion shapes created around the vessels. Computer simulations were then carried out to study the effect of different factors such as device-tissue contact, vessel position, and vessel-device distance on temperature distributions and thermal lesion shapes near a large vessel, specifically the portal vein. The geometries of thermal lesions around the vessels in the in vivo experiments were in agreement with the computer results. The thermal lesion shape created around the portal vein was significantly modified by the heat sink effect in all the cases considered. Thermal damage to the portal vein wall was inversely related to the vessel-device distance. It was also more pronounced when the device-tissue contact surface was reduced or when the vessel was parallel to the device or perpendicular to its distal end (blade zone), the vessel wall being damaged at distances less than 4.25 mm. The computational findings suggest that the heat sink effect could protect the portal vein wall for distances equal to or greater than 5 mm, regardless of its position and distance with respect to the RF-based device.

Automatic aneurysm neck detection using surface Voronoi diagrams.

PubMed

Cárdenes, Rubén; Pozo, José María; Bogunovic, Hrvoje; Larrabide, Ignacio; Frangi, Alejandro F

2011-10-01

A new automatic approach for saccular intracranial aneurysm isolation is proposed in this work. Due to the inter- and intra-observer variability in manual delineation of the aneurysm neck, a definition based on a minimum cost path around the aneurysm sac is proposed that copes with this variability and is able to make consistent measurements along different data sets, as well as to automate and speedup the analysis of cerebral aneurysms. The method is based on the computation of a minimal path along a scalar field obtained on the vessel surface, to find the aneurysm neck in a robust and fast manner. The computation of the scalar field on the surface is obtained using a fast marching approach with a speed function based on the exponential of the distance from the centerline bifurcation between the aneurysm dome and the parent vessels. In order to assure a correct topology of the aneurysm sac, the neck computation is constrained to a region defined by a surface Voronoi diagram obtained from the branches of the vessel centerline. We validate this method comparing our results in 26 real cases with manual aneurysm isolation obtained using a cut-plane, and also with results obtained using manual delineations from three different observers by comparing typical morphological measures. © 2011 IEEE

77 FR 60960 - Safety Zone, Coast Guard Exercise Area, Hood Canal, WA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-05

... to ensure the safety of the maritime public during these exercises, which involve fast moving surface... to Foul Weather Bluff. These exercises include fast moving surface vessels, smoke machines, and...

Interaction of Vascular Smooth Muscle Cells Under Low Shear Stress

NASA Technical Reports Server (NTRS)

Seidel, Charles L.

1998-01-01

The blood vessel wall consists of three cellular layers, an outer adventitial, a middle medial and an inner intimal layer. When the blood vessel forms in the embryo it begins as a tube composed of a single cell type called endothelial cells. Over time, other cells are recruited from the surrounding tissue to form additional layers on the outer surface of the endothelial tube. The cells that are recruited are called mesenchymal cells. Mesenchymal cells are responsible for the production of connective tissue that holds the blood vessel together and for developing into vascular smooth muscle cells that are responsible for regulating the diameter of the vessel (1) and therefore, blood flow. In a fully developed blood vessel, the endothelial cells make- up the majority of cells in the intimal layer while the mesenchymal cells make-up the majority of cells in the medial and adventitial layers. Within the medial layer of a mature vessel, cells are organized into multiple circular layers of alternating bands of connective tissue and cells. The cell layer is composed of a mixture of mesenchymal cells that have not developed into smooth muscle cells and fully developed smooth muscle cells (2). The assembly and organization of complex tissues is directed in part by a signaling system composed of proteins on the cell surface called adhesion molecules. Adhesion molecules enable cells to recognize each other as well as the composition of the connective tissue in which they reside (3). It was hypothesized that the different cell types that compose the vascular wall possess different adhesion molecules that enable them to recognize each other and through this recognition system, form the complex layered organization of the vascular wall. In other words, the layered organization is an intrinsic property of the cells. If this hypothesis is correct then the different cells that make up the vessel wall, when mixed together, should organize themselves into a layered structure resembling an intact blood vessel. Experiments described below were designed to test this hypothesis.

A Fundamental Study of Nucleate Pool Boiling Under Microgravity

NASA Technical Reports Server (NTRS)

Ervin, Jamie S.; Merte, Herman, Jr.

1996-01-01

An experimental study of incipient boiling in short-term microgravity and with a/g = +/- 1 for pool boiling was performed. Calibrated thin gold films sputtered on a smoothly polished quartz surface were used simultaneously for thermal-resistance measurements and heating of the boiling surface. The gold films were used for both transient and quasi-steady heating surface temperature measurements. Two test vessels were constructed for precise measurement and control of fluid temperature and pressure: a laboratory pool boiling vessel for the a/g = +/- 1 experiments and a pool boiling vessel designed for the 131 m free-fall in the NASA Lewis Research Center Microgravity Research Facility for the microgravity tests. Measurements included the heater surface temperature, the pressure near the heating surface, the bulk liquid temperatures. High speed photography (up to 1,000 frames per second) was used in the experiments. With high quality microgravity and the measured initial temperature of the quiescent test fluid, R113, the temperature distribution in the liquid at the moment of boiling inception resulting from an imposed step in heat flux is known with a certainty not possible previously. The types of boiling propagation across the large flat heating surface, some observed here for the first time, are categorized; the conditions necessary for their occurrence are described. Explosive boiling propagation with a striking pattern of small scale protuberances over the entire vapor mass periphery not observed previously at low heat flux levels (on the order of 5 W/cm(exp 2)) is described. For the heater surface with a/g = -1, a step in the heater surface temperature of short duration was imposed. The resulting liquid temperature distribution at the moment of boiling inception was different from that obtained with a step in heat flux.

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

Xiong, W; Zhou, Yunshen; Hou, Wenjia

Direct formation of graphene with controlled number of graphitic layers on dielectric surfaces is highly desired for practical applications. Despite significant progress achieved in understanding the formation of graphene on metallic surfaces through chemical vapor deposition (CVD) of hydrocarbons, very limited research is available elucidating the graphene formation process via rapid thermal processing (RTP) of solid-state amorphous carbon, through which graphene is formed directly on dielectric surfaces accompanied by autonomous nickel evaporation. It is suggested that a metastable hexagonal nickel carbide (Ni 3C) intermediate phase plays a critical role in transforming amorphous carbon to 2D crystalline graphene and contributing tomore » the autonomous Ni evaporation. Temperature resolved carbon and nickel evolution in the RTP process is investigated using Auger electron spectroscopic (AES) depth profiling and glancing-angle X-ray diffraction (GAXRD). Formation, migration and decomposition of the hexagonal Ni 3C are confirmed to be responsible for the formation of graphene and the evaporation of Ni at 1100 °C. The Ni 3C-assisted graphene formation mechanism expands the understanding of Ni-catalyzed graphene formation, and provides insightful guidance for controlled growth of graphene through the solid-state transformation process.« less

The potential risk of vessel infiltration and cervical lymph node metastasis in hypopharyngeal superficial squamous cell carcinoma: a retrospective observational study.

PubMed

Ebisumoto, Koji; Okami, Kenji; Sakai, Akihiro; Ogura, Go; Sugimoto, Ryousuke; Saito, Kosuke; Komita, Kaoru; Nakamura, Naoya; Iida, Masahiro

2015-07-01

The depth of hypopharyngeal superficial cancer may predict vessel infiltration and potential risk of cervical lymph node metastasis. To elucidate the histopathological predictors of vessel infiltration and the risk of regional lymph node metastasis in hypopharyngeal superficial cancer. This study included 31 lesions from 30 patients who had undergone transoral en bloc resection in the hospital. Patients with intraepithelial neoplasia or muscular invasion were excluded. Patient characteristics, nodal status, state of vessel infiltration, state of perineural invasion, histopathological parameters, and post-operative cervical lymph node recurrence were retrospectively examined. The histopathological parameters measured were tumor diameter and the following three parameters: tumor thickness, depth from the mucosal surface, and depth from the basement membrane. Correlations between histopathological parameters and state of vessel infiltration were statistically analyzed. Of the 31 lesions examined, four had vessel infiltration. Three of the four lesions with vessel infiltration had regional lymph node metastasis as well as subsequent lymph node metastasis. Lesions with vessel infiltration were significantly deeper than those without. In contrast, there was no significant difference in lesion diameters. In addition, there was no correlation between the depth and the diameter of the lesion.

Development and origins of zebrafish ocular vasculature.

PubMed

Kaufman, Rivka; Weiss, Omri; Sebbagh, Meyrav; Ravid, Revital; Gibbs-Bar, Liron; Yaniv, Karina; Inbal, Adi

2015-03-27

The developing eye receives blood supply from two vascular systems, the intraocular hyaloid system and the superficial choroidal vessels. In zebrafish, a highly stereotypic and simple set of vessels develops on the surface of the eye prior to development of choroidal vessels. The origins and formation of this so-called superficial system have not been described. We have analyzed the development of superficial vessels by time-lapse imaging and identified their origins by photoconversion experiments in kdrl:Kaede transgenic embryos. We show that the entire superficial system is derived from a venous origin, and surprisingly, we find that the hyaloid system has, in addition to its previously described arterial origin, a venous origin for specific vessels. Despite arising solely from a vein, one of the vessels in the superficial system, the nasal radial vessel (NRV), appears to acquire an arterial identity while growing over the nasal aspect of the eye and this happens in a blood flow-independent manner. Our results provide a thorough analysis of the early development and origins of zebrafish ocular vessels and establish the superficial vasculature as a model for studying vascular patterning in the context of the developing eye.

Distribution of lymphatic tissues and autonomic nerves in supporting ligaments around the cervix uteri.

PubMed

Zhang, Jianping; Feng, Lanlan; Lu, Yi; Guo, Dongxia; Xi, Tengteng; Wang, Xiaochun

2013-05-01

To investigate the distribution of lymphatic tissues and nerves in the supporting ligaments around the cervix uteri for their tomographical relationship, 9 adult female cadavers were used in this study. Following the incision of all supporting ligaments around the cervix, hematoxylin and esosin (H&E) and immunohistochemical staining of various sections of these ligaments was performed to enable the distribution of lymph tissues and autonomic nerves to be observed. Four lymph nodes were identified in three cadaver specimens. Three lymph nodes were present at a distance of 2.0 cm from the cervix in the cranial side of the cardinal ligaments (CLs), and one lymph node was located at a distance of 4.0 cm from the cervix in the cranial side of the uterosacral ligament (USL). The lymphatic vessels were dispersed in the CLs, scattered in the cervical side of the USLs, and occasionally distributed in the vesicouterine ligaments (VULs). In the CLs, parasympathetic nerves were located at the pelvic lateral wall and went downwards and medially into the cervix, while sympathetic fibers were located in the middle and lower parts of the ligaments. In the USLs, the autonomic nerves, which consisted primarily of sympathetic fibers, went downwards and laterally from the pelvic wall to the cervix. In the VULs, parasympathetic and sympathetic nerves were located in the inner sides of the vesical veins in the deep layers of the ligaments. It is concluded that there are few lymphatic tissues in the supporting ligaments around the cervix uteri, and that nerve‑sparing radical hysterectomy (NSRH) may be a safe method for the treatment of early‑stage cervical cancer.

Free-Flight Terrestrial Rocket Lander Demonstration for NASA's Autonomous Landing and Hazard Avoidance Technology (ALHAT) System

NASA Technical Reports Server (NTRS)

Rutishauser, David K.; Epp, Chirold; Robertson, Ed

2012-01-01

The Autonomous Landing Hazard Avoidance Technology (ALHAT) Project is chartered to develop and mature to a Technology Readiness Level (TRL) of six an autonomous system combining guidance, navigation and control with terrain sensing and recognition functions for crewed, cargo, and robotic planetary landing vehicles. The ALHAT System must be capable of identifying and avoiding surface hazards to enable a safe and accurate landing to within tens of meters of designated and certified landing sites anywhere on a planetary surface under any lighting conditions. Since its inception in 2006, the ALHAT Project has executed four field test campaigns to characterize and mature sensors and algorithms that support real-time hazard detection and global/local precision navigation for planetary landings. The driving objective for Government Fiscal Year 2012 (GFY2012) is to successfully demonstrate autonomous, real-time, closed loop operation of the ALHAT system in a realistic free flight scenario on Earth using the Morpheus lander developed at the Johnson Space Center (JSC). This goal represents an aggressive target consistent with a lean engineering culture of rapid prototyping and development. This culture is characterized by prioritizing early implementation to gain practical lessons learned and then building on this knowledge with subsequent prototyping design cycles of increasing complexity culminating in the implementation of the baseline design. This paper provides an overview of the ALHAT/Morpheus flight demonstration activities in GFY2012, including accomplishments, current status, results, and lessons learned. The ALHAT/Morpheus effort is also described in the context of a technology path in support of future crewed and robotic planetary exploration missions based upon the core sensing functions of the ALHAT system: Terrain Relative Navigation (TRN), Hazard Detection and Avoidance (HDA), and Hazard Relative Navigation (HRN).

Comparative safety assessment of surface versus submarine plutonium shipments

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

Knepper, D.S.; Feltus, M.A.

1993-01-01

The recent shipment of plutonium from France to Japan aboard the freighter Akatsuki Maru touched off protests from environmental and antinuclear organizations. These protests arose from the fear of an accidental sinking of the vessel that would release its cargo to the sea, as well as the threat of a terrorist nation highjacking the ship for its cargo to produce atomic weapons. The sinking of a merchant ship is not uncommon, as illustrated by the famous losses of the tankers Amoco Cadiz and Exxon Valdez. The highjacking of a lightly armed freighter such as the Akatsuki Maru is possible andmore » would not be unduly difficult for a well-equipped terrorist nation. The combined threats of weapons proliferation and environmental damage arising from the diversion or destruction of a sea vessel carrying plutonium will continue to abound as the reprocessing of spent nuclear fuel increases. An alternate method for the transportation with reduced risks of both diversion and destruction needs to be developed. The shipment aboard the Akatsuki Maru was originally proposed to be flown from France to Japan over the continental United States. This proposal was rejected by the Reagan administration in 1988. A third alternative to the current ideas of air transport and surface transport is subsurface transport. This research project investigates the transportation of plutonium by submarine and compares it to the current method of transportation by freighter. This analysis involves a study of the military threat to a submarine by a terrorist nation and comparable threat to a surface vessel. To study the nonmilitary aspects of plutonium shipping, a fault-tree evaluation is performed for transportation by submarine and compared with the current risk analysis performed for surface vessels.« less

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

McCormick, F.

A method for containment and deflection of inorganic and organic aqueous surface pollutants, such as an oil slick, flotsam, debris, and jellyfish, and an apparatus for the operation of such method are described. This method comprises the generation of an air or bubble barrier which permits the passage of surface vessels and large fish, but halts the movement of floating surface pollutants by the creation of a flexible continuous band of surface turbulence. The system in one specific application is designed to protect harbor and beach areas and fishing grounds from contamination with oil from oil tankers and also actsmore » as an air wall to keep harmful jellyfish from beach areas. The system can also be employed to recover oil from sunken or leaking tankers at sea by containment and collection of the oil released within the circumference of the bubble barrier wall created in a geometric pattern about the location of the stricken vessel. (10 claims)« less

Develop Critical Profilometers to Meet Current and Future Composite Overwrapped Pressure Vessel (COPV) Interior Inspection Needs

NASA Technical Reports Server (NTRS)

Saulsberry, Regor L.

2010-01-01

The objective of this project is to develop laser profilometer technology that can efficiently inspect and map the inside of composite pressure vessels for flaws such as liner buckling, pitting, or other surface imperfections. The project will also provide profilometers that can directly support inspections of flight vessels during development and qualification programs and subsequently be implemented into manufacturing inspections to screen out vessels with "out of family" liner defects. An example interior scan of a carbon overwrapped bottle is shown in comparison to an external view of the same bottle (Fig. 1). The internal scan is primarily of the cylindrical portion, but extends about 0.15 in. into the end cap area.

Cavity closure arrangement for high pressure vessels

DOEpatents

Amtmann, Hans H.

1981-01-01

A closure arrangement for a pressure vessel such as the pressure vessel of a high temperature gas-cooled reactor wherein a liner is disposed within a cavity penetration in the reactor vessel and defines an access opening therein. A closure is adapted for sealing relation with an annular mounting flange formed on the penetration liner and has a plurality of radially movable locking blocks thereon having outer serrations adapted for releasable interlocking engagement with serrations formed internally of the upper end of the penetration liner so as to effect high strength closure hold-down. In one embodiment, ramping surfaces are formed on the locking block serrations to bias the closure into sealed relation with the mounting flange when the locking blocks are actuated to locking positions.

Supercritical CO2 Cleaning System for Planetary Protection and Contamination Control Applications

NASA Technical Reports Server (NTRS)

Lin, Ying; Zhong, Fang; Aveline, David C.; Anderson, Mark S.

2012-01-01

Current spacecraft-compatible cleaning protocols involve a vapor degreaser, liquid sonication, and alcohol wiping. These methods are not very effective in removing live and dead microbes from spacecraft piece parts of slightly complicated geometry, such as tubing and loosely fitted nuts and bolts. Contamination control practices are traditionally focused on cleaning and monitoring of particulate and oily residual. Vapor degreaser and outgassing bakeout have not been proven to be effective in removing some less volatile, hydrophilic biomolecules of significant relevance to life detection. A precision cleaning technology was developed using supercritical CO2 (SCC). SCC is used as both solvent and carrier for removing organic and particulate contaminants. Supercritical fluid, like SCC, is characterized by physical and thermal properties that are between those of the pure liquid and gas phases. The fluid density is a function of the temperature and pressure. Its solvating power can be adjusted by changing the pressure or temperature, or adding a secondary solvent such as alcohol or water. Unlike a regular organic solvent, SCC has higher diffusivities, lower viscosity, and lower surface tension. It readily penetrates porous and fibrous solids and can reach hard-to-reach surfaces of the parts with complex geometry. Importantly, the CO2 solvent does not leave any residue. The results using this new cleaning device demonstrated that both supercritical CO2 with 5% water as a co-solvent can achieve cleanliness levels of 0.01 mg/cm2 or less for contaminants of a wide range of hydrophobicities. Experiments under the same conditions using compressed Martian air mix, which consists of 95% CO2, produced similar cleaning effectiveness on the hydrophobic compounds. The main components of the SCC cleaning system are a high-pressure cleaning vessel, a boil-off vessel located downstream from the cleaning vessel, a syringe-type high-pressure pump, a heat exchanger, and a back pressure regulator (BPR). After soaking the parts to be cleaned in the clean vessel for a period, the CO2 with contaminants is flushed out of the cleaning vessel using fresh CO2 in a first-in-first-out (FIFO) method. The contaminants are either precipitating out in the boil-off container or being trapped in a filter subsystem. The parts to be cleaned are secured in a basket inside and can be rotated up to 1,400 rpm by a magnetic drive. The fluid flows within the vessel generate tangential forces on the parts surfaces, enhancing the cleaning effectiveness and shortening the soaking time. During the FIFO flushing, the pump subsystem pushes fresh CO2 into the cleaning vessel at a constant flow rate between 0.01 and 200 mL/min, while the BPR regulates the pressure in the cleaning vessel to within 0.1 bar by controlling the needle position in an outlet valve. The fresh CO2 gas flows through the heat exchanger at a given temperature before entering the cleaning vessel. A platinum resistance thermometer (PRT) reads the cleaning vessel interior temperature that can be controlled to within 0.1 K. As a result, cleaning vessel temperature remains constant during the FIFO flushing. There is no change in solvent power during FIFO flushing since both temperature and pressure inside the cleaning vessel remain unchanged, thus minimizing contaminants left behind. During decompression, both temperature and pressure are strictly controlled to prevent bubbles from generating in the cleaning vessel that could stir up the contaminants that sank to the bottom by gravity.

Cardioprotective Properties of Aerobic and Resistance Training Against Myocardial Infarction.

PubMed

Barboza, C A; Souza, G I H; Oliveira, J C M F; Silva, L M; Mostarda, C T; Dourado, P M M; Oyama, L M; Lira, F S; Irigoyen, M C; Rodrigues, B

2016-06-01

We evaluated the effects of aerobic and resistance exercise training on ventricular morphometry and function, physical capacity, autonomic function, as well as on ventricular inflammatory status in trained rats prior to myocardial infarction. Male Wistar rats were divided into the following groups: sedentary+Sham, sedentary+myocardial infarction, aerobic trained+myocardial infarction, and resistance trained+myocardial infarction. Sham and myocardial infarction were performed after training periods. In the days following the surgeries, evaluations were performed. Aerobic training prevents aerobic (to a greater extent) and resistance capacity impairments, ventricular dysfunction, baroreflex sensitivity and autonomic disorders (vagal tonus decrease and sympathetic tonus increase) triggered by myocardial infarction. Resistance training was able to prevent negative changes to aerobic and resistance capacity (to a greater extent) but not to ventricular dysfunction, and it prevented cardiovascular sympathetic increments. Additionally, both types of training reduced left ventricle inflammatory cytokine concentration. Our results suggest that aerobic and, for the first time, dynamic resistance training were able to reduce sympathetic tonus to the heart and vessels, as well as preventing the increase in pro-inflammatory cytokine concentrations in the left ventricle of trained groups. These data emphasizes the positive effects of aerobic and dynamic resistance training on the prevention of the negative changes triggered by myocardial infarction. © Georg Thieme Verlag KG Stuttgart · New York.

Influence of cardiac nerve status on cardiovascular regulation and cardioprotection

PubMed Central

Kingma, John G; Simard, Denys; Rouleau, Jacques R

2017-01-01

Neural elements of the intrinsic cardiac nervous system transduce sensory inputs from the heart, blood vessels and other organs to ensure adequate cardiac function on a beat-to-beat basis. This inter-organ crosstalk is critical for normal function of the heart and other organs; derangements within the nervous system hierarchy contribute to pathogenesis of organ dysfunction. The role of intact cardiac nerves in development of, as well as protection against, ischemic injury is of current interest since it may involve recruitment of intrinsic cardiac ganglia. For instance, ischemic conditioning, a novel protection strategy against organ injury, and in particular remote conditioning, is likely mediated by activation of neural pathways or by endogenous cytoprotective blood-borne substances that stimulate different signalling pathways. This discovery reinforces the concept that inter-organ communication, and maintenance thereof, is key. As such, greater understanding of mechanisms and elucidation of treatment strategies is imperative to improve clinical outcomes particularly in patients with comorbidities. For instance, autonomic imbalance between sympathetic and parasympathetic nervous system regulation can initiate cardiovascular autonomic neuropathy that compromises cardiac stability and function. Neuromodulation therapies that directly target the intrinsic cardiac nervous system or other elements of the nervous system hierarchy are currently being investigated for treatment of different maladies in animal and human studies. PMID:28706586

Analysis and design of a capsule landing system and surface vehicle control system for Mars exploration. [performance tests of remote control equipment for roving vehicles

NASA Technical Reports Server (NTRS)

Gisser, D. G.; Frederick, D. K.; Sandor, G. N.; Shen, C. N.; Yerazunis, S. W.

1976-01-01

Problems related to the design and control of an autonomous rover for the purpose of unmanned exploration of the planets were considered. Building on the basis of prior studies, a four wheeled rover of unusual mobility and maneuverability was further refined and tested under both laboratory and field conditions. A second major effort was made to develop autonomous guidance. Path selection systems capable of dealing with relatively formidable hazard and terrains involving various short range (1.0-3.0 meters), hazard detection systems using a triangulation detection concept were simulated and evaluated. The mechanical/electronic systems required to implement such a scheme were constructed and tested. These systems include: laser transmitter, photodetectors, the necessary data handling/controlling systems and a scanning mast. In addition, a telemetry system to interface the vehicle, the off-board computer and a remote control module for operator intervention were developed. Software for the autonomous control concept was written. All of the systems required for complete autonomous control were shown to be satisfactory except for that portion of the software relating to the handling of interrupt commands.

Autonomous path-planning navigation system for site characterization

NASA Astrophysics Data System (ADS)

Rankin, Arturo L.; Crane, Carl D., III; Armstrong, David G., II; Nease, Allen D.; Brown, H. Edward

1996-05-01

The location and removal of buried munitions is an important yet hazardous task. Current development is aimed at performing both the ordnance location and removal tasks autonomously. An autonomous survey vehicle (ASV) named the Gator has been developed at the Center for Intelligent Machines and Robotics, under the direction of Wright Laboratory, Tyndall Air Force Base, Florida, and the Navy Explosive Ordnance Disposal Technology Division, Indian Head, Maryland. The primary task of the survey vehicle is to autonomously traverse an off-road site, towing behind it a trailer containing a sensor package capable of characterizing the sub-surface contents. Achieving 00 percent coverage of the site is critical to fully characterizing the site. This paper presents a strategy for planning efficient paths for the survey vehicle that guarantees near-complete coverage of a site. A small library of three in-house developed path planners are reviewed. A strategy is also presented to keep the trailer on-path and to calculate the percent of coverage of a site with a resolution of 0.01 m2. All of the algorithms discussed in this paper were initially developed in simulation on a Silicon Graphics computer and subsequently implemented on the survey vehicle.

33 CFR 165.T01-1130 - Regulated Navigation Area; S99 Alford Street Bridge rehabilitation project, Mystic River, MA.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Navigation Area (RNA): All navigable waters of the Mystic River between Boston and Chelsea, MA, from surface... vessel by siren, radio, flashing light or other means, the operator of the vessel must proceed as... the date and time that enforcement is suspended as well as the date and time that enforcement will...

33 CFR 165.T01-1130 - Regulated Navigation Area; S99 Alford Street Bridge rehabilitation project, Mystic River, MA.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Navigation Area (RNA): All navigable waters of the Mystic River between Boston and Chelsea, MA, from surface... vessel by siren, radio, flashing light or other means, the operator of the vessel must proceed as... the date and time that enforcement is suspended as well as the date and time that enforcement will...

33 CFR 165.T01-1125 - Regulated Navigation Area; S99 Alford Street Bridge rehabilitation project, Mystic River, MA

Code of Federal Regulations, 2012 CFR

2012-07-01

... Navigation Area (RNA): All navigable waters of the Mystic River between Boston and Chelsea, MA, from surface... vessel by siren, radio, flashing light or other means, the operator of the vessel must proceed as... the date and time that enforcement is suspended as well as the date and time that enforcement will...

Distributed sensing of Composite Over-wrapped Pressure Vessel using Fiber-Bragg Gratings at Ambient and Cryogenic Temperatures

NASA Technical Reports Server (NTRS)

Grant, Joseph

2005-01-01

Fiber Bragg gratings are use to monitor the structural properties of composite pressure vessels. These gratings optically inscribed into the core of a single mode fiber are used as a tool to monitor the stress strain relation in laminate structure. The fiber Bragg sensors are both embedded within the composite laminates and bonded to the surface of the vessel with varying orientations with respect to the carbon fiber in the epoxy matrix. The response of these fiber-optic sensors is investigated by pressurizing the cylinder up to its burst pressure of around 2800 psi. This is done at both ambient and cryogenic temperatures using water and liquid nitrogen. The recorded response is compared with the response from conventional strain gauge also present on the vessel. Additionally, several vessels were tested that had been damaged to simulate different type of events, such as cut tow, delimitation and impact damage.

Distributed Sensing of Composite Over-wrapped Pressure Vessel Using Fiber-Bragg Gratings at Ambient and Cryogenic Temperatures

NASA Technical Reports Server (NTRS)

Grant, Joseph

2004-01-01

Fiber Bragg gratings are use to monitor the structural properties of composite pressure vessels. These gratings optically inscribed into the core of a single mode fiber are used as a tool to monitor the stress strain relation in laminate structure. The fiber Bragg sensors are both embedded within the composite laminates and bonded to the surface of the vessel with varying orientations with respect to the carbon fiber in the epoxy matrix. The response of these fiber-optic sensors is investigated by pressurizing the cylinder up to its burst pressure of around 2800 psi. This is done at both ambient and cryogenic temperatures using water and liquid nitrogen. The recorded response is compared with the response from conventional strain gauge also present on the vessel. Additionally, several vessels were tested that had been damaged to simulate different type of events, such as cut tow, delimitation and impact damage.

Tissue Engineering of Blood Vessels: Functional Requirements, Progress, and Future Challenges.

PubMed

Kumar, Vivek A; Brewster, Luke P; Caves, Jeffrey M; Chaikof, Elliot L

2011-09-01

Vascular disease results in the decreased utility and decreased availability of autologus vascular tissue for small diameter (< 6 mm) vessel replacements. While synthetic polymer alternatives to date have failed to meet the performance of autogenous conduits, tissue-engineered replacement vessels represent an ideal solution to this clinical problem. Ongoing progress requires combined approaches from biomaterials science, cell biology, and translational medicine to develop feasible solutions with the requisite mechanical support, a non-fouling surface for blood flow, and tissue regeneration. Over the past two decades interest in blood vessel tissue engineering has soared on a global scale, resulting in the first clinical implants of multiple technologies, steady progress with several other systems, and critical lessons-learned. This review will highlight the current inadequacies of autologus and synthetic grafts, the engineering requirements for implantation of tissue-engineered grafts, and the current status of tissue-engineered blood vessel research.

Dangerous dining: surface foraging of North Atlantic right whales increases risk of vessel collisions.

PubMed

Parks, Susan E; Warren, Joseph D; Stamieszkin, Karen; Mayo, Charles A; Wiley, David

2012-02-23

North Atlantic right whales are critically endangered and, despite international protection from whaling, significant numbers die from collisions with ships. Large groups of right whales migrate to the coastal waters of New England during the late winter and early spring to feed in an area with large numbers of vessels. North Atlantic right whales have the largest per capita record of vessel strikes of any large whale population in the world. Right whale feeding behaviour in Cape Cod Bay (CCB) probably contributes to risk of collisions with ships. In this study, feeding right whales tagged with archival suction cup tags spent the majority of their time just below the water's surface where they cannot be seen but are shallow enough to be vulnerable to ship strike. Habitat surveys show that large patches of right whale prey are common in the upper 5 m of the water column in CCB during spring. These results indicate that the typical spring-time foraging ecology of right whales may contribute to their high level of mortality from vessel collisions. The results of this study suggest that remote acoustic detection of prey aggregations may be a useful supplement to the management and conservation of right whales.

Bone marrow blood vessel ossification and "microvascular dead space" in rat and human long bone.

PubMed

Prisby, Rhonda D

2014-07-01

Severe calcification of the bone microvascular network was observed in rats, whereby the bone marrow blood vessels appeared ossified. This study sought to characterize the magnitude of ossification in relation to patent blood vessels and adipocyte content in femoral diaphyses. Additionally, this study confirmed the presence of ossified vessels in patients with arteriosclerotic vascular disease and peripheral vascular disease and cellulitis. Young (4-6 month; n=8) and old (22-24 month; n=8) male Fischer-344 rats were perfused with barium sulfate to visualize patent bone marrow blood vessels. Femoral shafts were processed for bone histomorphometry to quantify ossified (Goldner's Trichrome) and calcified (Alizarin Red) vessels. Adipocyte content was also determined. Additional femora (n=5/age group) were scanned via μCT to quantify microvascular ossification. Bone marrow blood vessels from the rats and the human patients were also isolated and examined via microscopy. Ossified vessels (rats and humans) had osteocyte lacunae on the vessel surfaces and "normal" vessels were transitioning into bone. The volume of ossified vessels was 4800% higher (p<0.05) in the old vs. young rats. Calcified and ossified vessel volumes per tissue volume and calcified vessel volume per patent vessel volume were augmented (p<0.05) 262%, 375% and 263%, respectively, in the old vs. young rats. Ossified and patent vessel number was higher (171%) and lower (40%), respectively, in the old vs. young rats. Finally, adipocyte volume per patent vessel volume was higher (86%) with age. This study is the first to report ossification of bone marrow blood vessels in rats and humans. Ossification presumably results in "microvascular dead space" in regard to loss of patency and vasomotor function as opposed to necrosis. Progression of bone microvascular ossification may provide the common link associated with age-related changes in bone and bone marrow. The clinical implications may be evident in the difficulties treating bone disease in the elderly. Copyright © 2014 Elsevier Inc. All rights reserved.

Bone Marrow Blood Vessel Ossification and “Microvascular Dead Space” in Rat and Human Long Bone

PubMed Central

Prisby, Rhonda D.

2014-01-01

Severe calcification of the bone microvascular network was observed in rats, whereby the bone marrow blood vessels appeared ossified. This study sought to characterize the magnitude of ossification in relation to patent blood vessels and adipocyte content in femoral diaphyses. Additionally, this study confirmed the presence of ossified vessels in patients with arteriosclerotic vascular disease and peripheral vascular disease and cellulitis. Young (4–6 mon; n=8) and old (22–24 mon; n=8) male Fischer-344 rats were perfused with barium sulfate to visualize patent bone marrow blood vessels. Femoral shafts were processed for bone histomorphometry to quantify ossified (Goldner’s Trichrome) and calcified (Alizarin Red) vessels. Adipocyte content was also determined. Additional femora (n=5/age group) were scanned via µCT to quantify microvascular ossification. Bone marrow blood vessels from rats and the human patients were also isolated and examined via microscopy. Ossified vessels (rats and humans) had osteocyte lacunae on the vessel surfaces and “normal” vessels were transitioning into bone. The volume of ossified vessels was 4800% higher (p <0.05) in old vs. young rats. Calcified and ossified vessel volumes per tissue volume and calcified vessel volume per patent vessel volume were augmented (p <0.05) 262%, 375% and 263%, respectively, in old vs. young rats. Ossified and patent vessel number was higher (171%) and lower (40%), respectively, in old vs. young rats. Finally, adipocyte volume per patent vessel volume was higher (86%) with age. This study is the first to report ossification of bone marrow blood vessels in rats and humans. Ossification presumably results in “microvascular dead space” in regards to loss of patency and vasomotor function as opposed to necrosis. The progression of bone microvascular ossification may provide the common link associated with age-related changes in bone and bone marrow. The clinical implications may be evident in the difficulties treating bone disease in the elderly. PMID:24680721

Monitoring the Wall Mechanics During Stent Deployment in a Vessel

PubMed Central

Steinert, Brian D.; Zhao, Shijia; Gu, Linxia

2012-01-01

Clinical trials have reported different restenosis rates for various stent designs1. It is speculated that stent-induced strain concentrations on the arterial wall lead to tissue injury, which initiates restenosis2-7. This hypothesis needs further investigations including better quantifications of non-uniform strain distribution on the artery following stent implantation. A non-contact surface strain measurement method for the stented artery is presented in this work. ARAMIS stereo optical surface strain measurement system uses two optical high speed cameras to capture the motion of each reference point, and resolve three dimensional strains over the deforming surface8,9. As a mesh stent is deployed into a latex vessel with a random contrasting pattern sprayed or drawn on its outer surface, the surface strain is recorded at every instant of the deformation. The calculated strain distributions can then be used to understand the local lesion response, validate the computational models, and formulate hypotheses for further in vivo study. PMID:22588353

Shallow Water MCM and ASW Using Off-Board, Autonomous Sensor Networks and Multistatic, Time-Reversal Acoustics

DTIC Science & Technology

2005-09-30

generalizations of auto-focusing and track - before - detect (TBD) algorithms. Another issue concerns the stability and coherence of surface and seabed multiples and their potential use in advanced medium-frequency sonar concepts.

A three-dimensional autonomous nonlinear dynamical system modelling equatorial ocean flows

NASA Astrophysics Data System (ADS)

Ionescu-Kruse, Delia

2018-04-01

We investigate a nonlinear three-dimensional model for equatorial flows, finding exact solutions that capture the most relevant geophysical features: depth-dependent currents, poleward or equatorial surface drift and a vertical mixture of upward and downward motions.

Unmanned surface vessel (USV) systems for bridge inspection : final report.

DOT National Transportation Integrated Search

2016-08-01

The use of unmanned surface vehicles (USVs) for bridge inspection has been explored. The following issues were considered: (1) the requirements of and : current techniques utilized in on-water bridge inspection; (2) USV design and configuration consi...

Shipping container for fissile material

DOEpatents

Crowder, H.E.

1984-12-17

The present invention is directed to a shipping container for the interstate transportation of enriched uranium materials. The shipping container is comprised of a rigid, high-strength, cylindrical-shaped outer vessel lined with thermal insulation. Disposed inside the thermal insulation and spaced apart from the inner walls of the outer vessel is a rigid, high-strength, cylindrical inner vessel impervious to liquid and gaseous substances and having the inner surfaces coated with a layer of cadmium to prevent nuclear criticality. The cadmium is, in turn, lined with a protective shield of high-density urethane for corrosion and wear protection. 2 figs.

Calculation with MCNP of capture photon flux in VVER-1000 experimental reactor.

PubMed

Töre, Candan; Ortego, Pedro

2005-01-01

The aim of this study is to obtain by Monte Carlo method the high energy photon flux due to neutron capture in the internals and vessel layers of the experimental reactor LR-0 located in REZ, Czech Republic, and loaded with VVER-1000 fuel. The calclated neutron, photon and photon to neutron flux ratio are compared with experimental measurements performed with a multi-parameter stilbene detector. The results show clear underestimation of photon flux in downcomer and some overestimation at vessel surface and 1/4 thickness but a good fitting for deeper points in vessel.

Trawler Icing: A Compilation of Work Done at N.R.C. (Givrage des Chalutiers: Compilation des Recherches Effectuees au C.N.R.).

DTIC Science & Technology

1980-12-01

stability of fishing vessels of the Inter-Governmental Maritime (’onsultative Organization 1M(’()). it has been found convenient to express the degree of...Stability of Fishing Vessels. Intergovernmental Maritime Consultative Organization , Londm, 1 969. 42. Stallabrass, ,J.R. Icing of Fishing Vessels: An...ovirlinkrd Iniwexir that soic o)f tlIm iiii𔃽iii.1ia \\vatcr x Ill likcly ’Iaslh (I run t1I the iIg surface, hefore reacliui thit( -ul hu tempe33rattirl I

100-kWe lunar/Mars surface power utilizing the SP-100 reactor with dynamic conversion

NASA Technical Reports Server (NTRS)

Harty, Richard B.; Mason, Lee S.

1992-01-01

Results are presented from a study of the coupling of an SP-100 nuclear reactor with either a Stirling or Brayton power system, at the 100 kWe level, for a power generating system suitable for operation in the lunar and Martian surface environments. In the lunar environment, the reactor and primary coolant loop would be contained in a guard vessel to protect from a loss of primary loop containment. For Mars, all refractory components, including the reactor, coolant, and power conversion components will be contained in a vacuum vessel for protection against the CO2 environment.

Six stirrup handled Moche ceramic vessels from pre-Colombian Peru: a technical study applying PIXE spectrometry

NASA Astrophysics Data System (ADS)

Swann, C. P.; Caspi, Sara; Carlson, Janice

1999-04-01

Much has been said recently concerning the Moche culture of Peru (100 B.C. to 700 A.D. ) which preceded the more widely known Inca society. Since there was no written language, what is known about the Moche people has been through the artifacts produced, their design and craftsmanship. This study concerns the PIXE analysis of the matrix and the red and white surface patterns of six stirrup handled earthenware vessels. The results suggest different techniques were applied for producing the coloring and surface designs and that a common source of clays was not used in the construction.

ALI (Autonomous Lunar Investigator): Revolutionary Approach to Exploring the Moon with Addressable Reconfigurable Technology

NASA Technical Reports Server (NTRS)

Clark, P. E.; Curtis, S. A.; Rilee, M. L.; Floyd, S. R.

2005-01-01

Addressable Reconfigurable Technology (ART) based structures: Mission Concepts based on Addressable Reconfigurable Technology (ART), originally studied for future ANTS (Autonomous Nanotechnology Swarm) Space Architectures, are now being developed as rovers for nearer term use in lunar and planetary surface exploration. The architecture is based on the reconfigurable tetrahedron as a building block. Tetrahedra are combined to form space-filling networks, shaped for the required function. Basic structural components are highly modular, addressable arrays of robust nodes (tetrahedral apices) from which highly reconfigurable struts (tetrahedral edges), acting as supports or tethers, are efficiently reversibly deployed/stowed, transforming and reshaping the structures as required.

Autonomous movement of silica and glass micro-objects based on a catalytic molecular propulsion system.

PubMed

Stock, Christoph; Heureux, Nicolas; Browne, Wesley R; Feringa, Ben L

2008-01-01

A general approach for the easy functionalization of bare silica and glass surfaces with a synthetic manganese catalyst is reported. Decomposition of H(2)O(2) by this dinuclear metallic center into H(2)O and O(2) induced autonomous movement of silica microparticles and glass micro-sized fibers. Although several mechanisms have been proposed to rationalise movement of particles driven by H(2)O(2) decomposition to O(2) and water (recoil from O(2) bubbles, ([36,45]) interfacial tension gradient([37-42]), it is apparent in the present system that ballistic movement is due to the growth of O(2) bubbles.

Stochastic estimates of gradient from laser measurements for an autonomous Martian roving vehicle

NASA Technical Reports Server (NTRS)

Burger, P. A.

1973-01-01

The general problem of estimating the state vector x from the state equation h = Ax where h, A, and x are all stochastic, is presented. Specifically, the problem is for an autonomous Martian roving vehicle to utilize laser measurements in estimating the gradient of the terrain. Error exists due to two factors - surface roughness and instrumental measurements. The errors in slope depend on the standard deviations of these noise factors. Numerically, the error in gradient is expressed as a function of instrumental inaccuracies. Certain guidelines for the accuracy of permissable gradient must be set. It is found that present technology can meet these guidelines.

Planetary surface exploration MESUR/autonomous lunar rover

NASA Astrophysics Data System (ADS)

Stauffer, Larry; Dilorenzo, Matt; Austin, Dave; Ayers, Raymond; Burton, David; Gaylord, Joe; Kennedy, Jim; Laux, Richard; Lentz, Dale; Nance, Preston

Planetary surface exploration micro-rovers for collecting data about the Moon and Mars have been designed by the Department of Mechanical Engineering at the University of Idaho. The goal of both projects was to design a rover concept that best satisfied the project objectives for NASA/Ames. A second goal was to facilitate student learning about the process of design. The first micro-rover is a deployment mechanism for the Mars Environmental Survey (MESUR) Alpha Particle/Proton/X-ray (APX) Instrument. The system is to be launched with the 16 MESUR landers around the turn of the century. A Tubular Deployment System and a spiked-legged walker have been developed to deploy the APX from the lander to the Martian Surface. While on Mars, the walker is designed to take the APX to rocks to obtain elemental composition data of the surface. The second micro-rover is an autonomous, roving vehicle to transport a sensor package over the surface of the moon. The vehicle must negotiate the lunar terrain for a minimum of one year by surviving impacts and withstanding the environmental extremes. The rover is a reliable track-driven unit that operates regardless of orientation that NASA can use for future lunar exploratory missions. This report includes a detailed description of the designs and the methods and procedures which the University of Idaho design teams followed to arrive at the final designs.

Planetary surface exploration: MESUR/autonomous lunar rover

NASA Astrophysics Data System (ADS)

Stauffer, Larry; Dilorenzo, Matt; Austin, Dave; Ayers, Raymond; Burton, David; Gaylord, Joe; Kennedy, Jim; Lentz, Dale; Laux, Richard; Nance, Preston

1992-06-01

Planetary surface exploration micro-rovers for collecting data about the Moon and Mars was designed by the Department of Mechanical Engineering at the University of Idaho. The goal of both projects was to design a rover concept that best satisfied the project objectives for NASA-Ames. A second goal was to facilitate student learning about the process of design. The first micro-rover is a deployment mechanism for the Mars Environmental SURvey (MESUR) Alpha Particle/Proton/X-ray instruments (APX). The system is to be launched with the sixteen MESUR landers around the turn of the century. A Tubular Deployment System and a spiked-legged walker was developed to deploy the APX from the lander to the Martian surface. While on Mars the walker is designed to take the APX to rocks to obtain elemental composition data of the surface. The second micro-rover is an autonomous, roving vehicle to transport a sensor package over the surface of the moon. The vehicle must negotiate the lunar-terrain for a minimum of one year by surviving impacts and withstanding the environmental extremes. The rover is a reliable track-driven unit that operates regardless of orientation which NASA can use for future lunar exploratory missions. A detailed description of the designs, methods, and procedures which the University of Idaho design teams followed to arrive at the final designs are included.

Planetary surface exploration MESUR/autonomous lunar rover

NASA Technical Reports Server (NTRS)

Stauffer, Larry; Dilorenzo, Matt; Austin, Dave; Ayers, Raymond; Burton, David; Gaylord, Joe; Kennedy, Jim; Laux, Richard; Lentz, Dale; Nance, Preston

1992-01-01

Planetary surface exploration micro-rovers for collecting data about the Moon and Mars have been designed by the Department of Mechanical Engineering at the University of Idaho. The goal of both projects was to design a rover concept that best satisfied the project objectives for NASA/Ames. A second goal was to facilitate student learning about the process of design. The first micro-rover is a deployment mechanism for the Mars Environmental Survey (MESUR) Alpha Particle/Proton/X-ray (APX) Instrument. The system is to be launched with the 16 MESUR landers around the turn of the century. A Tubular Deployment System and a spiked-legged walker have been developed to deploy the APX from the lander to the Martian Surface. While on Mars, the walker is designed to take the APX to rocks to obtain elemental composition data of the surface. The second micro-rover is an autonomous, roving vehicle to transport a sensor package over the surface of the moon. The vehicle must negotiate the lunar terrain for a minimum of one year by surviving impacts and withstanding the environmental extremes. The rover is a reliable track-driven unit that operates regardless of orientation that NASA can use for future lunar exploratory missions. This report includes a detailed description of the designs and the methods and procedures which the University of Idaho design teams followed to arrive at the final designs.

Planetary surface exploration: MESUR/autonomous lunar rover

NASA Technical Reports Server (NTRS)

Stauffer, Larry; Dilorenzo, Matt; Austin, Dave; Ayers, Raymond; Burton, David; Gaylord, Joe; Kennedy, Jim; Lentz, Dale; Laux, Richard; Nance, Preston

1992-01-01

Planetary surface exploration micro-rovers for collecting data about the Moon and Mars was designed by the Department of Mechanical Engineering at the University of Idaho. The goal of both projects was to design a rover concept that best satisfied the project objectives for NASA-Ames. A second goal was to facilitate student learning about the process of design. The first micro-rover is a deployment mechanism for the Mars Environmental SURvey (MESUR) Alpha Particle/Proton/X-ray instruments (APX). The system is to be launched with the sixteen MESUR landers around the turn of the century. A Tubular Deployment System and a spiked-legged walker was developed to deploy the APX from the lander to the Martian surface. While on Mars the walker is designed to take the APX to rocks to obtain elemental composition data of the surface. The second micro-rover is an autonomous, roving vehicle to transport a sensor package over the surface of the moon. The vehicle must negotiate the lunar-terrain for a minimum of one year by surviving impacts and withstanding the environmental extremes. The rover is a reliable track-driven unit that operates regardless of orientation which NASA can use for future lunar exploratory missions. A detailed description of the designs, methods, and procedures which the University of Idaho design teams followed to arrive at the final designs are included.

46 CFR 170.295 - Special consideration for free surface of passive roll stabilization tanks.

Code of Federal Regulations, 2014 CFR

2014-10-01

... the moment of inertia of the free surface in the roll tank; (ii) (d) is the density of the liquid in... 46 Shipping 7 2014-10-01 2014-10-01 false Special consideration for free surface of passive roll...) SUBDIVISION AND STABILITY STABILITY REQUIREMENTS FOR ALL INSPECTED VESSELS Free Surface § 170.295 Special...

46 CFR 170.295 - Special consideration for free surface of passive roll stabilization tanks.

Code of Federal Regulations, 2012 CFR

2012-10-01

... the moment of inertia of the free surface in the roll tank; (ii) (d) is the density of the liquid in... 46 Shipping 7 2012-10-01 2012-10-01 false Special consideration for free surface of passive roll...) SUBDIVISION AND STABILITY STABILITY REQUIREMENTS FOR ALL INSPECTED VESSELS Free Surface § 170.295 Special...

46 CFR 170.295 - Special consideration for free surface of passive roll stabilization tanks.

Code of Federal Regulations, 2013 CFR

2013-10-01

... the moment of inertia of the free surface in the roll tank; (ii) (d) is the density of the liquid in... 46 Shipping 7 2013-10-01 2013-10-01 false Special consideration for free surface of passive roll...) SUBDIVISION AND STABILITY STABILITY REQUIREMENTS FOR ALL INSPECTED VESSELS Free Surface § 170.295 Special...

46 CFR 170.300 - Special consideration for free surface of spoil in hopper dredge hoppers.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 7 2014-10-01 2014-10-01 false Special consideration for free surface of spoil in hopper dredge hoppers. 170.300 Section 170.300 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY STABILITY REQUIREMENTS FOR ALL INSPECTED VESSELS Free Surface § 170.300...

Three Dimensional Guidance for the NPS Autonomous Underwater Vehicle

DTIC Science & Technology

1991-09-01

is loaded into a least-squares-fit algorithm to determine surfaces of polyhedrons . These computed surfaces are then compared with the known...the obstacle information stored in the vehicle’s environmental database , there is great potential of encountering unplanned for obstacles during the... database that holds current posture information recorded by the navigator. This data store receives a new current posture on each cycle of the control

Cardiovascular and temperature changes in spinal cord injured rats at rest and during autonomic dysreflexia

PubMed Central

Laird, A S; Carrive, P; Waite, P M E

2006-01-01

In patients with high spinal cord injuries autonomic dysfunction can be dangerous, leading to medical complications such as postural hypotension, autonomic dysreflexia and temperature disturbance. While animal models have been developed to study autonomic dysreflexia, associated temperature changes have not been documented. Our aim here was to use radiotelemetry and infrared thermography in rodents to record the development of cardiovascular and skin temperature changes following complete T4 transection. In adult male Wistar rats (n = 5), responses were assessed prior to spinal cord injury (intact) and for 6 weeks following injury. Statistical analysis by a repeated-measure ANOVA revealed that following spinal cord injury (SCI), rats exhibited decreased mean arterial pressure (MAP, average decrease of 26 mmHg; P < 0.035) and elevated heart rate (HR, average increase of 65 bpm, P < 0.035) at rest. The basal core body temperature following SCI was also significantly lower than intact levels (−0.9°C; P < 0.0035). Associated with this decreased basal core temperature following SCI was an increased skin temperature of the mid-tail and hindpaw (+5.6 and +4.0°C, respectively; P < 0.0003) consistent with decreased cutaneous vasoconstrictor tone. Autonomic dysreflexia, in response to a 1 min colorectal distension (25 mmHg), was fully developed by 4 weeks after spinal cord transection, producing increases in MAP greater than 25 mmHg (P < 0.0003). In contrast to the tachycardia seen in intact animals in response to colorectal distension, SCI animals exhibited bradycardia (P < 0.0023). During episodes of autonomic dysreflexia mid-tail surface temperature decreased (approx. −1.7°C, P < 0.012), consistent with cutaneous vasoconstriction. This is the first study to compare cardiovascular dysfunction with temperature changes following spinal cord transection in rats. PMID:16973703

Behavioral and biological effects of autonomous versus scheduled mission management in simulated space-dwelling groups

NASA Astrophysics Data System (ADS)

Roma, Peter G.; Hursh, Steven R.; Hienz, Robert D.; Emurian, Henry H.; Gasior, Eric D.; Brinson, Zabecca S.; Brady, Joseph V.

2011-05-01

Logistical constraints during long-duration space expeditions will limit the ability of Earth-based mission control personnel to manage their astronaut crews and will thus increase the prevalence of autonomous operations. Despite this inevitability, little research exists regarding crew performance and psychosocial adaptation under such autonomous conditions. To this end, a newly-initiated study on crew management systems was conducted to assess crew performance effectiveness under rigid schedule-based management of crew activities by Mission Control versus more flexible, autonomous management of activities by the crews themselves. Nine volunteers formed three long-term crews and were extensively trained in a simulated planetary geological exploration task over the course of several months. Each crew then embarked on two separate 3-4 h missions in a counterbalanced sequence: Scheduled, in which the crews were directed by Mission Control according to a strict topographic and temporal region-searching sequence, and Autonomous, in which the well-trained crews received equivalent baseline support from Mission Control but were free to explore the planetary surface as they saw fit. Under the autonomous missions, performance in all three crews improved (more high-valued geologic samples were retrieved), subjective self-reports of negative emotional states decreased, unstructured debriefing logs contained fewer references to negative emotions and greater use of socially-referent language, and salivary cortisol output across the missions was attenuated. The present study provides evidence that crew autonomy may improve performance and help sustain if not enhance psychosocial adaptation and biobehavioral health. These controlled experimental data contribute to an emerging empirical database on crew autonomy which the international astronautics community may build upon for future research and ultimately draw upon when designing and managing missions.

Reactive Swarm Formation Control Using Realistic Surface Vessel Dynamics and Environmental Effects

DTIC Science & Technology

2012-05-10

hour per response, including the time for reviewing instructions. searching existing data sources. gathering and maintaining the data needed, and...1997, 2001, 2003, % % %(#) Department fo Automation % Danish Technical University, DTU . % DK 2800 Kgs. Lyngby, Denmark...tristan.perez@ntnu.no % Date: 2005-05-04 % Comments: %Adapted from the files reference (*) to match the data of the vessel %design of ADI-Limited

Postnatal development of autonomic and sensory innervation of thoracic hairy skin in the rat. A histochemical, immunocytochemical, and radioenzymatic study.

PubMed

Schotzinger, R J; Landis, S C

1990-05-01

Histochemical, immunocytochemical, and radioenzymatic techniques were used to examine the neurotransmitter-related properties of the innervation of thoracic hairy skin in rats during adulthood and postnatal development. In the adult, catecholamine-containing fibers were associated with blood vessels and piloerector muscles, and ran in nerve bundles throughout the dermis. The distribution of tyrosine hydroxylase (TH)-immunoreactive (IR) fibers was identical. Neuronal fibers displaying neuropeptide Y (NPY) immunoreactivity were seen in association with blood vessels. Double-labeling studies suggested that most, if not all, NPY-IR fibers were also TH-IR and likewise most, if not all, vessel-associated TH-IR fibers were also NPY-IR. Calcitonin gene-related peptide (CGRP)-IR fibers were observed near and penetrating into the epidermis, in close association with hair follicles and blood vessels, and in nerve bundles. A similar distribution of substance P (SP)-IR fibers was evident. In adult animals treated as neonates with the sympathetic neurotoxin 6-hydroxydopamine, a virtual absence of TH-IR and NPY-IR fibers was observed, whereas the distribution of CGRP-IR and SP-IR fibers appeared unaltered. During postnatal development, a generalized increase in the number, fluorescence intensity, and varicose morphology of neuronal fibers displaying catecholamine fluorescence, NPY-IR, CGRP-IR, and SP-IR was observed. By postnatal day 21, the distribution of the above fibers had reached essentially adult levels, although the density of epidermal-associated CGRP-IR and SP-IR fibers was significantly greater than in the adult. The following were not evident in thoracic hairy skin at any timepoint examined: choline acetyltransferase activity, acetylcholinesterase histochemical staining or immunoreactivity, fibers displaying immunoreactivity to vasoactive intestinal peptide, cholecystokinin, or leucine-enkephalin. The present study demonstrates that the thoracic hairy skin in developing and adult rats receives an abundant sympathetic catecholaminergic and sensory innervation, but not a cholinergic innervation.

Limited Versus Total Epithelial Debridement Ocular Surface Injury: Live Fluorescence Imaging of Hemangiogenesis and Lymphangiogenesis in Prox1-GFP/Flk1::myr-mCherry Mice

PubMed Central

Chang, Jin-Hong; Putra, Ilham; Huang, Yu-hui; Chang, Michael; Han, Kyuyeon; Zhong, Wei; Gao, Xinbo; Wang, Shuangyong; Dugas-Ford, Jennifer; Nguyen, Tara; Hong, Young-Kwon; Azar, Dimitri T.

2016-01-01

Background Immunohistochemical staining experiments have shown that both hemangiogenesis and lymphangiogenesis occur following severe corneal and conjunctival injury and that the neovascularization of the cornea often has severe visual consequences. To better understand how hemangiogenesis and lymphangiogenesis are induced by different degrees of ocular injury, we investigated patterns of injury-induced corneal neovascularization in live Prox1-GFP/Flk1::myr-mCherry mice, in which blood and lymphatic vessels can be imaged simultaneously in vivo. Methods The eyes of Prox1-GFP/Flk1::myr-mCherry mice were injured according to four models based on epithelial debridement of the: A) central cornea (a 1.5-mm-diameter circle of tissue over the corneal apex), B) total cornea, C) bulbar conjunctiva, and D) cornea+bulbar conjunctiva. Corneal blood and lymphatic vessels were imaged on days 0, 3, 7, and 10 post-injury, and the percentages of the cornea containing blood and lymphatic vessels were calculated. Results Neither central corneal nor bulbar conjunctival debridement resulted in significant vessel growth in the mouse cornea, whereas total corneal and corneal+bulbar conjunctival debridement did. On day 10 in the central cornea, total cornea, bulbar conjunctiva, and corneal+bulbar conjunctival epithelial debridement models, the percentage of the corneal surface that was occupied by blood vessels (hemangiogenesis) was 1.9±0.8%, 7.14±2.4%, 2.29±1%, and 15.05±2.14%, respectively, and the percentage of the corneal surface that was occupied by lymphatic vessels (lymphangiogenesis) was 2.45±1.51%, 4.85±0.95%, 2.95±1.27%, and 4.15±3.85%, respectively. Conclusions Substantial corneal debridement was required to induce corneal neovascularization in the mouse cornea, and the corneal epithelium may therefore be partially responsible for maintaining corneal avascularity. General significance Our study demonstrates that GFP/Flk1::myr-mCherry mice are a useful model for studying coordinated hemangiogenic and lymphangiogenic responses. PMID:27233452

77 FR 47282 - Drawbridge Operation Regulation; Lewis and Clark River, Astoria, OR

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-08

... roadway surface on the lift span. DATES: This deviation is effective from 7 a.m. on August 29, 2012..., remain closed to vessel traffic to facilitate the milling and repaving of the roadway surface on the lift...

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

Chang, Shih-Jung

Dynamic strength of the High Flux Isotope Reactor (HFIR) vessel to resist hypothetical accidents is analyzed by using the method of fracture mechanics. Vessel critical stresses are estimated by applying dynamic pressure pulses of a range of magnitudes and pulse-durations. The pulses versus time functions are assumed to be step functions. The probability of vessel fracture is then calculated by assuming a distribution of possible surface cracks of different crack depths. The probability distribution function for the crack depths is based on the form that is recommended by the Marshall report. The toughness of the vessel steel used in themore » analysis is based on the projected and embrittled value after 10 effective full power years from 1986. From the study made by Cheverton, Merkle and Nanstad, the weakest point on the vessel for fracture evaluation is known to be located within the region surrounding the tangential beam tube HB3. The increase in the probability of fracture is obtained as an extension of the result from that report for the regular operating condition to include conditions of higher dynamic pressures due to accident loadings. The increase in the probability of vessel fracture is plotted for a range of hoop stresses to indicate the vessel strength against hypothetical accident conditions.« less

MicroCT angiography detects vascular formation and regression in skin wound healing

PubMed Central

Urao, Norifumi; Okonkwo, Uzoagu A.; Fang, Milie M.; Zhuang, Zhen W.; Koh, Timothy J.; DiPietro, Luisa A.

2016-01-01

Properly regulated angiogenesis and arteriogenesis are essential for effective wound healing. Tissue injury induces robust new vessel formation and subsequent vessel maturation, which involves vessel regression and remodeling. Although formation of functional vasculature is essential for healing, alterations in vascular structure over the time course of skin wound healing are not well understood. Here, using high-resolution ex vivo X-ray micro-computed tomography (microCT), we describe the vascular network during healing of skin excisional wounds with highly detailed three-dimensional (3D) reconstructed images and associated quantitative analysis. We found that relative vessel volume, surface area and branching number are significantly decreased in wounds from day 7 to day 14 and 21. Segmentation and skeletonization analysis of selected branches from high-resolution images as small as 2.5 μm voxel size show that branching orders are decreased in the wound vessels during healing. In histological analysis, we found that the contrast agent fills mainly arterioles, but not small capillaries nor large veins. In summary, high-resolution microCT revealed dynamic alterations of vessel structures during wound healing. This technique may be useful as a key tool in the study of the formation and regression of wound vessels. PMID:27009591

Heating equipment installation system

DOEpatents

Meuschke, Robert E.; Pomaibo, Paul P.

1991-01-01

A method for installing a heater unit assembly (52, 54) in a reactor pressure vessel (2) for performance of an annealing treatment on the vessel (2), the vessel (2) having a vertical axis, being open at the top, being provided at the top with a flange (6) having a horizontal surface, and being provided internally, at a location below the flange (6), with orientation elements (8) which are asymmetrical with respect to the vertical axis, by the steps of: providing an orientation fixture (10) having an upwardly extending guide member (18) and orientation elements (14, 16) and installing the orientation fixture (10) in the vessel (2) so that the orientation elements (14,16) of the orientation fixture (10) mate with the orientation elements (8) of the pressure vessel (2) in order to establish a defined position of the orientation fixture (10) in the pressure vessel (2), and so that the guide member (18) projects above the pressure vessel (2) flange (6); placing a seal ring (30) in a defined position on the pressure vessel (2) flange (6) with the aid of the guide member (18); mounting at least one vertical, upwardly extending guide stud (40) upon the seal ring (30); withdrawing the orientation fixture (10) from the pressure vessel (2); and moving the heater unit assembly (52,54) vertically downwardly into the pressure vessel (2) while guiding the heater unit assembly (52,54) along a path with the aid of the guide stud (40).

Astrobiology Science and Technology: A Path to Future Discovery

NASA Technical Reports Server (NTRS)

Meyer, M. A.; Lavaery, D. B.

2001-01-01

The Astrobiology Program is described. However, science-driven robotic exploration of extreme environments is needed for a new era of planetary exploration requiring biologically relevant instrumentation and extensive, autonomous operations on planetary surfaces. Additional information is contained in the original extended abstract.

Titan Aerial Daughtercraft (TAD) for Surface Studies from a Lander or Balloon

NASA Astrophysics Data System (ADS)

Matthies, L.; Tokumaru, P.; Sherrit, S.; Beauchamp, P.

2014-06-01

Recent rapid progress on autonomous navigation of micro air vehicles for terrestrial applications opens new possibilities for a small aerial vehicle that could deploy from a Titan lander or balloon to acquire samples for analysis on the mothership.

GAS COOLED NUCLEAR REACTORS

DOEpatents

Long, E.; Rodwell, W.

1958-06-10

A gas-cooled nuclear reactor consisting of a graphite reacting core and reflector structure supported in a containing vessel is described. A gas sealing means is included for sealing between the walls of the graphite structure and containing vessel to prevent the gas coolant by-passing the reacting core. The reacting core is a multi-sided right prismatic structure having a pair of parallel slots around its periphery. The containing vessel is cylindrical and has a rib on its internal surface which supports two continuous ring shaped flexible web members with their radially innermost ends in sealing engagement within the radially outermost portion of the slots. The core structure is supported on ball bearings. This design permits thermal expansion of the core stracture and vessel while maintainirg a peripheral seal between the tvo elements.

Self-cleaning of superhydrophobic surfaces by spontaneously jumping condensate drops

NASA Astrophysics Data System (ADS)

Wisdom, Katrina; Watson, Jolanta; Watson, Gregory; Chen, Chuan-Hua

2012-11-01

The self-cleaning function of superhydrophobic surfaces is conventionally attributed to the removal of contaminating particles by impacting or rolling water droplets, which implies the action of external forces such as gravity. Here, we demonstrate a new self-cleaning mechanism, whereby condensate drops spontaneously jump upon coalescence on a superhydrophobic surface, and the merged drop self-propels away from the surface along with the contaminants. The jumping-condensate mechanism is shown to autonomously clean superhydrophobic cicada wings, where the contaminating particles cannot be removed by external wind flow. Our findings offer new insights for the development of self-cleaning materials.

The effects of sustained manual pressure stimulation according to Vojta Therapy on heart rate variability.

PubMed

Opavsky, Jaroslav; Slachtova, Martina; Kutin, Miroslav; Hok, Pavel; Uhlir, Petr; Opavska, Hana; Hlustik, Petr

2018-05-23

The physiotherapeutic technique of Vojta reflex locomotion is often accompanied by various autonomic activity changes and unpleasant sensations. It is unknown whether these effects are specific to Vojta Therapy. Therefore, the aim of this study was to compare changes in cardiac autonomic control after Vojta reflex locomotion stimulation and after an appropriate sham stimulation. A total of 28 young healthy adults (20.4 - 25.7 years) were enrolled in this single-blind randomized cross-over study. Participants underwent two modes of 20-minute sustained manual pressure stimulation on the surface of the foot on two separate visits. One mode used manual pressure on the lateral heel, i.e., in a zone employed in the Vojta Therapy (active stimulation). The other mode used pressure on the lateral ankle (control), in an area not included among the active zones used by Vojta Therapy and whose activation does not evoke manifestations of reflex locomotion. Autonomic nervous system activity was evaluated using spectral analysis of heart rate variability before and after the intervention. The active stimulation was perceived as more unpleasant than the control stimulation. Heart rate variability parameters demonstrated almost identical autonomic responses after both stimulation types, showing either modest increase in parasympathetic activity, or increased heart rate variability with similar contribution of parasympathetic and sympathetic activity. The results demonstrate changes of cardiac autonomic control in both active and control stimulation, without evidence for a significant difference between the two.

Proposing an International Collaboration on Lightweight Autonomous Vehicles to Conduct Scientific Traverses and Surveys over Antarctica and the Surrounding Sea Ice

NASA Technical Reports Server (NTRS)

Carsey, Frank; Behar, Alberto

2004-01-01

We have continued to develop a concept for use of autonomous rovers, originally developed for use in planetary exploration, in polar science on Earth; the concept was the subject of a workshop, and this report summarizes and extends that workshop. The workshop on Antarctic Autonomous Scientific Vehicles and Traverses met at the National Geographic Society on February 14 and 15, 2001 to discuss scientific objectives and benefits of the use of autonomous rovers. The participants enthusiastically viewed rovers as being uniquely valuable for such tasks as data taking on tedious or repetitive routes, traverses in polar night, difficult or hazardous routes, extremely remote regions, routes requiring only simple instrumentation, traverses that must be conducted at low speed, augments of manned traverses, and scientific procedures not compatible with human presence or combustion engines. The workshop has concluded that instrumented autonomous vehicles, of the type being developed for planetary exploration, have the potential to contribute significantly to the way science in conducted in Antarctica while also aiding planetary technology development, and engaging the public's interest. Specific objectives can be supported in understanding ice sheet mass balance, sea ice heat and momentum exchange, and surface air chemistry processes. In the interval since the workshop, we have concluded that organized program to employ such rovers to perform scientific tasks in the Fourth International Polar Year would serve the objectives of that program well.

ANTS: Applying A New Paradigm for Lunar and Planetary Exploration

NASA Technical Reports Server (NTRS)

Clark, P. E.; Curtis, S. A.; Rilee, M. L.

2002-01-01

ANTS (Autonomous Nano- Technology Swarm), a mission architecture consisting of a large (1000 member) swarm of picoclass (1 kg) totally autonomous spacecraft with both adaptable and evolvable heuristic systems, is being developed as a NASA advanced mission concept, and is here examined as a paradigm for lunar surface exploration. As the capacity and complexity of hardware and software, demands for bandwidth, and the sophistication of goals for lunar and planetary exploration have increased, greater cost constraints have led to fewer resources and thus, the need to operate spacecraft with less frequent human contact. At present, autonomous operation of spacecraft systems allows great capability of spacecraft to 'safe' themselves and survive when conditions threaten spacecraft safety. To further develop spacecraft capability, NASA is at the forefront of development of new mission architectures which involve the use of Intelligent Software Agents (ISAs), performing experiments in space and on the ground to advance deliberative and collaborative autonomous control techniques. Selected missions in current planning stages require small groups of spacecraft weighing tens, instead of hundreds, of kilograms to cooperate at a tactical level to select and schedule measurements to be made by appropriate instruments onboard. Such missions will be characterizing rapidly unfolding real-time events on a routine basis. The next level of development, which we are considering here, is in the use of autonomous systems at the strategic level, to explore the remote terranes, potentially involving large surveys or detailed reconnaissance.

Low cycle fatigue behavior of a ferritic reactor pressure vessel steel

NASA Astrophysics Data System (ADS)

Sarkar, Apu; Kumawat, Bhupendra K.; Chakravartty, J. K.

2015-07-01

The cyclic stress-strain response and the low cycle fatigue (LCF) behavior of 20MnMoNi55 pressure vessel steel were studied. Tensile strength and LCF properties were examined at room temperature (RT) using specimens cut from rolling direction of a rolled block. The fully reversed strain-controlled LCF tests were conducted at a constant total strain rate with different axial strain amplitude levels. The cyclic strain-stress relationships and the strain-life relationships were obtained through the test results, and related LCF parameters of the steel were calculated. The studied steel exhibits cyclic softening behavior. Furthermore, analysis of stabilized hysteresis loops showed that the steel exhibits non-Masing behavior. Complementary scanning electron microscopy examinations were also carried out on fracture surfaces to reveal dominant damage mechanisms during crack initiation, propagation and fracture. Multiple crack initiation sites were observed on the fracture surface. The investigated LCF behavior can provide reference for pressure vessel life assessment and fracture mechanisms analysis.

[Burnout syndrome: a "true" cardiovascular risk factor].

PubMed

Cursoux, Pauline; Lehucher-Michel, Marie-Pascale; Marchetti, Hélène; Chaumet, Guillaume; Delliaux, Stéphane

2012-11-01

The burnout syndrome is characterized by emotional exhaustion, depersonalization and reduced personal accomplishment in individuals professionally involved with others. The burnout syndrome is poorly recognized, particularly in France, as a distinct nosology from adaptation troubles, stress, depression, or anxiety. Several tools quantifying burnout and emotional exhaustion exist, the most spread is the questionnaire called Maslach Burnout Inventory. The burnout syndrome alters cardiovascular function and its neuroregulation by autonomic nervous system and is associated with: increased sympathetic tone to heart and vessels after mental stress, lowered physiological post-stress vagal rebound to heart, and lowered arterial baroreflex sensitivity. Job strain as burnout syndrome seems to be a real independent cardiovascular risk factor. Oppositely, training to manage emotions could increase vagal tone to heart and should be cardio-protective. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Autonomic innervation of the fish gut.

PubMed

Olsson, Catharina

2009-01-01

The enteric nervous system follows a similar overall arrangement in all vertebrate groups. In fish, the majority of nerve cell bodies are found in the myenteric plexus, innervating muscles, blood vessels and glands. In this review, I describe similarities and differences in size, shape and transmitter content in enteric neurons in different fish species and also in comparison with other vertebrates, foremost mammals. The use of different histological and immunochemical methods is reviewed in a historical perspective including advantages and disadvantages of different methods. Lately, zebrafish have become an important model species for developmental studies of the nervous system, including the enteric nervous system, and this is briefly discussed. Finally, examples of how the enteric nervous system controls gut activity in fish is presented, focussing on the effect on gastrointestinal motility.

Cost efficient environmental survey paths for detecting continuous tracer discharges

NASA Astrophysics Data System (ADS)

Alendal, G.

2017-07-01

Designing monitoring programs for detecting potential tracer discharges from unknown locations is challenging. The high variability of the environment may camouflage the anticipated anisotropic signal from a discharge, and there are a number of discharge scenarios. Monitoring operations may also be costly, constraining the number of measurements taken. By assuming that a discharge is active, and a prior belief on the most likely seep location, a method that uses Bayes' theorem combined with discharge footprint predictions is used to update the probability map. Measurement locations with highest reduction in the overall probability of a discharge to be active can be identified. The relative cost between reallocating and measurements can be taken into account. Three different strategies are suggested to enable cost efficient paths for autonomous vessels.

The cardiovascular system in the ageing patient

PubMed Central

Moore, A; Mangoni, A A; Lyons, D; Jackson, S H D

2003-01-01

The ageing process is associated with important changes in the responses of the cardiovascular system to pharmacological stimuli. They are not limited to the arterial system, involved in the modulation of cardiac afterload and vascular resistance, but they also involve the low-resistance capacitance venous system and the heart. The main changes include loss of large artery compliance, dysfunction of some of the systems modulating resistance vessel tone, increased activity of the sympathetic nervous system, and reduced haemodynamic responses to inotropic agents. This review focuses on the effects of ageing on arterial and venous reactivity to drugs and hormones, the autonomic nervous system, and the cardiovascular responses to inotropic agents. Some of the age-related changes might be at least partially reversible. This may have important therapeutic implications. PMID:12919173

A Simple Criterion to Estimate Performance of Pulse Jet Mixed Vessels

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

Pease, Leonard F.; Bamberger, Judith A.; Mahoney, Lenna A.

Pulse jet mixed process vessels comprise a key element of the U.S. Department of Energy’s strategy to process millions of gallons of legacy nuclear waste slurries. Slurry suctioned into a pulse jet mixer (PJM) tube at the end of one pulse is pneumatically driven from the PJM toward the bottom of the vessel at the beginning of the next pulse, forming a jet. The jet front traverses the distance from nozzle outlet to the bottom of the vessel and spreads out radially. Varying numbers of PJMs are typically arranged in a ring configuration within the vessel at a selected radiusmore » and operated concurrently. Centrally directed radial flows from neighboring jets collide to create a central upwell that elevates the solids in the center of the vessel when the PJM tubes expel their contents. An essential goal of PJM operation is to elevate solids to the liquid surface to minimize stratification. Solids stratification may adversely affect throughput of the waste processing plant. Unacceptably high slurry densities at the base of the vessel may plug the pipeline through which the slurry exits the vessel. Additionally, chemical reactions required for processing may not achieve complete conversion. To avoid these conditions, a means of predicting the elevation to which the solids rise in the central upwell that can be used during vessel design remains essential. In this paper we present a simple criterion to evaluate the extent of solids elevation achieved by a turbulent upwell jet. The criterion asserts that at any location in the central upwell the local velocity must be in excess of a cutoff velocity to remain turbulent. We find that local velocities in excess of 0.6 m/s are necessary for turbulent jet flow through both Newtonian and yield stress slurries. By coupling this criterion with the free jet velocity equation relating the local velocity to elevation in the central upwell, we estimate the elevation at which turbulence fails, and consequently the elevation at which the upwell fails to further lift the slurry. Comparing this elevation to the vessel fill level predicts whether the jet flow will achieve the full vertical extent of the vessel at the center. This simple local-velocity criterion determines a minimum PJM nozzle velocity at which the full vertical extent of the central upwell in PJM vessels will be turbulent. The criterion determines a minimum because flow in regions peripheral to the central upwelling jet may not be turbulent, even when the center of the vessel in the upwell is turbulent, if the jet pulse duration is too short. The local-velocity criterion ensures only that there is sufficient wherewithal for the turbulent jet flow to drive solids to the surface in the center of the vessel in the central upwell.« less

Noninvasive method for determining the liquid level and density inside of a container

DOEpatents

Sinha, Dipen N.

2000-01-01

Noninvasive method for determining the liquid level and density inside of a container having arbitrary dimension and shape. By generating a flexural acoustic wave in the container shell and measuring the phase difference of the detected flexural wave from that of the originally generated wave a small distance from the generated wave, while moving the generation and detection means through the liquid/vapor interface, this interface can be detected. Both the wave generation and wave detection may be achieved by transducers on the surface of the container. A change in the phase difference over the outer surface of the vessel signifies that a liquid/vapor interface has been crossed, while the magnitude of the phase difference can be related to fluid density immediately opposite the measurement position on the surface of the vessel.

Real-Time Hazard Detection and Avoidance Demonstration for a Planetary Lander

NASA Technical Reports Server (NTRS)

Epp, Chirold D.; Robertson, Edward A.; Carson, John M., III

2014-01-01

The Autonomous Landing Hazard Avoidance Technology (ALHAT) Project is chartered to develop and mature to a Technology Readiness Level (TRL) of six an autonomous system combining guidance, navigation and control with terrain sensing and recognition functions for crewed, cargo, and robotic planetary landing vehicles. In addition to precision landing close to a pre-mission defined landing location, the ALHAT System must be capable of autonomously identifying and avoiding surface hazards in real-time to enable a safe landing under any lighting conditions. This paper provides an overview of the recent results of the ALHAT closed loop hazard detection and avoidance flight demonstrations on the Morpheus Vertical Testbed (VTB) at the Kennedy Space Center, including results and lessons learned. This effort is also described in the context of a technology path in support of future crewed and robotic planetary exploration missions based upon the core sensing functions of the ALHAT system: Terrain Relative Navigation (TRN), Hazard Detection and Avoidance (HDA), and Hazard Relative Navigation (HRN).

Autonomous Repair Mechanism of Creep Damage in Fe-Au and Fe-Au-B-N Alloys

NASA Astrophysics Data System (ADS)

Zhang, S.; Kwakernaak, C.; Tichelaar, F. D.; Sloof, W. G.; Kuzmina, M.; Herbig, M.; Raabe, D.; Brück, E.; van der Zwaag, S.; van Dijk, N. H.

2015-12-01

The autonomous repair mechanism of creep cavitation during high-temperature deformation has been investigated in Fe-Au and Fe-Au-B-N alloys. Combined electron-microscopy techniques and atom probe tomography reveal how the improved creep properties result from Au precipitation within the creep cavities, preferentially formed on grain boundaries oriented perpendicular to the applied stress. The selective precipitation of Au atoms at the free creep cavity surface results in pore filling, and thereby, autonomous repair of the creep damage. The large difference in atomic size between the Au and Fe strongly hampers the nucleation of precipitates in the matrix. As a result, the matrix acts as a reservoir for the supersaturated solute until damage occurs. Grain boundaries and dislocations are found to act as fast transport routes for solute gold from the matrix to the creep cavities. The mechanism responsible for the self-healing can be characterized by a simple model for cavity growth and cavity filling.

Advanced 3D mesh manipulation in stereolithographic files and post-print processing for the manufacturing of patient-specific vascular flow phantoms

NASA Astrophysics Data System (ADS)

O'Hara, Ryan P.; Chand, Arpita; Vidiyala, Sowmya; Arechavala, Stacie M.; Mitsouras, Dimitrios; Rudin, Stephen; Ionita, Ciprian N.

2016-03-01

Complex vascular anatomies can cause the failure of image-guided endovascular procedures. 3D printed patient-specific vascular phantoms provide clinicians and medical device companies the ability to preemptively plan surgical treatments, test the likelihood of device success, and determine potential operative setbacks. This research aims to present advanced mesh manipulation techniques of stereolithographic (STL) files segmented from medical imaging and post-print surface optimization to match physiological vascular flow resistance. For phantom design, we developed three mesh manipulation techniques. The first method allows outlet 3D mesh manipulations to merge superfluous vessels into a single junction, decreasing the number of flow outlets and making it feasible to include smaller vessels. Next we introduced Boolean operations to eliminate the need to manually merge mesh layers and eliminate errors of mesh self-intersections that previously occurred. Finally we optimize support addition to preserve the patient anatomical geometry. For post-print surface optimization, we investigated various solutions and methods to remove support material and smooth the inner vessel surface. Solutions of chloroform, alcohol and sodium hydroxide were used to process various phantoms and hydraulic resistance was measured and compared with values reported in literature. The newly mesh manipulation methods decrease the phantom design time by 30 - 80% and allow for rapid development of accurate vascular models. We have created 3D printed vascular models with vessel diameters less than 0.5 mm. The methods presented in this work could lead to shorter design time for patient specific phantoms and better physiological simulations.

Advanced 3D Mesh Manipulation in Stereolithographic Files and Post-Print Processing for the Manufacturing of Patient-Specific Vascular Flow Phantoms.

PubMed

O'Hara, Ryan P; Chand, Arpita; Vidiyala, Sowmya; Arechavala, Stacie M; Mitsouras, Dimitrios; Rudin, Stephen; Ionita, Ciprian N

2016-02-27

Complex vascular anatomies can cause the failure of image-guided endovascular procedures. 3D printed patient-specific vascular phantoms provide clinicians and medical device companies the ability to preemptively plan surgical treatments, test the likelihood of device success, and determine potential operative setbacks. This research aims to present advanced mesh manipulation techniques of stereolithographic (STL) files segmented from medical imaging and post-print surface optimization to match physiological vascular flow resistance. For phantom design, we developed three mesh manipulation techniques. The first method allows outlet 3D mesh manipulations to merge superfluous vessels into a single junction, decreasing the number of flow outlets and making it feasible to include smaller vessels. Next we introduced Boolean operations to eliminate the need to manually merge mesh layers and eliminate errors of mesh self-intersections that previously occurred. Finally we optimize support addition to preserve the patient anatomical geometry. For post-print surface optimization, we investigated various solutions and methods to remove support material and smooth the inner vessel surface. Solutions of chloroform, alcohol and sodium hydroxide were used to process various phantoms and hydraulic resistance was measured and compared with values reported in literature. The newly mesh manipulation methods decrease the phantom design time by 30 - 80% and allow for rapid development of accurate vascular models. We have created 3D printed vascular models with vessel diameters less than 0.5 mm. The methods presented in this work could lead to shorter design time for patient specific phantoms and better physiological simulations.

Advanced 3D Mesh Manipulation in Stereolithographic Files and Post-Print Processing for the Manufacturing of Patient-Specific Vascular Flow Phantoms

PubMed Central

O’Hara, Ryan P.; Chand, Arpita; Vidiyala, Sowmya; Arechavala, Stacie M.; Mitsouras, Dimitrios; Rudin, Stephen; Ionita, Ciprian N.

2017-01-01

Complex vascular anatomies can cause the failure of image-guided endovascular procedures. 3D printed patient-specific vascular phantoms provide clinicians and medical device companies the ability to preemptively plan surgical treatments, test the likelihood of device success, and determine potential operative setbacks. This research aims to present advanced mesh manipulation techniques of stereolithographic (STL) files segmented from medical imaging and post-print surface optimization to match physiological vascular flow resistance. For phantom design, we developed three mesh manipulation techniques. The first method allows outlet 3D mesh manipulations to merge superfluous vessels into a single junction, decreasing the number of flow outlets and making it feasible to include smaller vessels. Next we introduced Boolean operations to eliminate the need to manually merge mesh layers and eliminate errors of mesh self-intersections that previously occurred. Finally we optimize support addition to preserve the patient anatomical geometry. For post-print surface optimization, we investigated various solutions and methods to remove support material and smooth the inner vessel surface. Solutions of chloroform, alcohol and sodium hydroxide were used to process various phantoms and hydraulic resistance was measured and compared with values reported in literature. The newly mesh manipulation methods decrease the phantom design time by 30 – 80% and allow for rapid development of accurate vascular models. We have created 3D printed vascular models with vessel diameters less than 0.5 mm. The methods presented in this work could lead to shorter design time for patient specific phantoms and better physiological simulations. PMID:28649165

The embodied dynamics of perceptual causality: a slippery slope?

PubMed Central

Amorim, Michel-Ange; Siegler, Isabelle A.; Baurès, Robin; Oliveira, Armando M.

2015-01-01

In Michotte's launching displays, while the launcher (object A) seems to move autonomously, the target (object B) seems to be displaced passively. However, the impression of A actively launching B does not persist beyond a certain distance identified as the “radius of action” of A over B. If the target keeps moving beyond the radius of action, it loses its passivity and seems to move autonomously. Here, we manipulated implied friction by drawing (or not) a surface upon which A and B are traveling, and by varying the inclination of this surface in screen- and earth-centered reference frames. Among 72 participants (n = 52 in Experiment 1; n = 20 in Experiment 2), we show that both physical embodiment of the event (looking straight ahead at a screen displaying the event on a vertical plane vs. looking downwards at the event displayed on a horizontal plane) and contextual information (objects moving along a depicted surface or in isolation) affect interpretation of the event and modulate the radius of action of the launcher. Using classical mechanics equations, we show that representational consistency of friction from radius of action responses emphasizes the embodied nature of frictional force in our cognitive architecture. PMID:25954235

The embodied dynamics of perceptual causality: a slippery slope?

PubMed

Amorim, Michel-Ange; Siegler, Isabelle A; Baurès, Robin; Oliveira, Armando M

2015-01-01

In Michotte's launching displays, while the launcher (object A) seems to move autonomously, the target (object B) seems to be displaced passively. However, the impression of A actively launching B does not persist beyond a certain distance identified as the "radius of action" of A over B. If the target keeps moving beyond the radius of action, it loses its passivity and seems to move autonomously. Here, we manipulated implied friction by drawing (or not) a surface upon which A and B are traveling, and by varying the inclination of this surface in screen- and earth-centered reference frames. Among 72 participants (n = 52 in Experiment 1; n = 20 in Experiment 2), we show that both physical embodiment of the event (looking straight ahead at a screen displaying the event on a vertical plane vs. looking downwards at the event displayed on a horizontal plane) and contextual information (objects moving along a depicted surface or in isolation) affect interpretation of the event and modulate the radius of action of the launcher. Using classical mechanics equations, we show that representational consistency of friction from radius of action responses emphasizes the embodied nature of frictional force in our cognitive architecture.

Containment control of networked autonomous underwater vehicles: A predictor-based neural DSC design.

PubMed

Peng, Zhouhua; Wang, Dan; Wang, Wei; Liu, Lu

2015-11-01

This paper investigates the containment control problem of networked autonomous underwater vehicles in the presence of model uncertainty and unknown ocean disturbances. A predictor-based neural dynamic surface control design method is presented to develop the distributed adaptive containment controllers, under which the trajectories of follower vehicles nearly converge to the dynamic convex hull spanned by multiple reference trajectories over a directed network. Prediction errors, rather than tracking errors, are used to update the neural adaptation laws, which are independent of the tracking error dynamics, resulting in two time-scales to govern the entire system. The stability property of the closed-loop network is established via Lyapunov analysis, and transient property is quantified in terms of L2 norms of the derivatives of neural weights, which are shown to be smaller than the classical neural dynamic surface control approach. Comparative studies are given to show the substantial improvements of the proposed new method. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.

Robotics development for the enhancement of space endeavors

NASA Astrophysics Data System (ADS)

Mauceri, A. J.; Clarke, Margaret M.

Telerobotics and robotics development activities to support NASA's goal of increasing opportunities in space commercialization and exploration are described. The Rockwell International activities center is using robotics to improve efficiency and safety in three related areas: remote control of autonomous systems, automated nondestructive evaluation of aspects of vehicle integrity, and the use of robotics in space vehicle ground reprocessing operations. In the first area, autonomous robotic control, Rockwell is using the control architecture, NASREM, as the foundation for the high level command of robotic tasks. In the second area, we have demonstrated the use of nondestructive evaluation (using acoustic excitation and lasers sensors) to evaluate the integrity of space vehicle surface material bonds, using Orbiter 102 as the test case. In the third area, Rockwell is building an automated version of the present manual tool used for Space Shuttle surface tile re-waterproofing. The tool will be integrated into an orbiter processing robot being developed by a KSC-led team.

Measurement of atmospheric surface layer turbulence using unmanned aerial vehicles

NASA Astrophysics Data System (ADS)

Bailey, Sean; Canter, Caleb

2017-11-01

We describe measurements of the turbulence within the atmospheric surface layer using highly instrumented and autonomous unmanned aerial vehicles (UAVs). Results from the CLOUDMAP measurement campaign in Stillwater Oklahoma are presented including turbulence statistics measured during the transition from stably stratified to convective conditions. The measurements were made using pre-fabricated fixed-wing remote-control aircraft adapted to fly autonomously and carry multi-hole pressure probes, pressure, temperature and humidity sensors. Two aircraft were flown simultaneously, with one flying a flight path intended to profile the boundary layer up to 100 m and the other flying at a constant fixed altitude of 50 m. The evolution of various turbulent statistics was determined from these flights, including Reynolds stresses, correlations, spectra and structure functions. These results were compared to those measured by a sonic anemometer located on a 7.5 m tower. This work was supported by the National Science Foundation through Grant #CBET-1351411 and by National Science Foundation award #1539070, Collaboration Leading Operational UAS Development for Meteorology and Atmospheric Physics (CLOUDMAP).

Measurement of atmospheric surface layer turbulence using unmanned aerial vehicles

NASA Astrophysics Data System (ADS)

Witte, Brandon; Smith, Lorli; Schlagenhauf, Cornelia; Bailey, Sean

2016-11-01

We describe measurements of the turbulence within the atmospheric surface layer using highly instrumented and autonomous unmanned aerial vehicles (UAVs). Results from the CLOUDMAP measurement campaign in Stillwater Oklahoma are presented including turbulence statistics measured during the transition from stably stratified to convective conditions. The measurements were made using pre-fabricated fixed-wing remote-control aircraft adapted to fly autonomously and carry multi-hole pressure probes, pressure, temperature and humidity sensors. Two aircraft were flown simultaneously, with one flying a flight path intended to profile the boundary layer up to 100 m and the other flying at a constant fixed altitude of 50 m. The evolution of various turbulent statistics was determined from these flights, including Reynolds stresses, correlations, spectra and structure functions. These results were compared to those measured by a sonic anemometer located on a 7.5 m tower. This work was supported by the National Science Foundation through Grant #CBET-1351411 and by National Science Foundation award #1539070, Collaboration Leading Operational UAS Development for Meteorology and Atmospheric Physics (CLOUDMAP).

Detection of compression vessels in trigeminal neuralgia by surface-rendering three-dimensional reconstruction of 1.5- and 3.0-T magnetic resonance imaging.

PubMed

Shimizu, Masahiro; Imai, Hideaki; Kagoshima, Kaiei; Umezawa, Eriko; Shimizu, Tsuneo; Yoshimoto, Yuhei

2013-01-01

Surface-rendered three-dimensional (3D) 1.5-T magnetic resonance (MR) imaging is useful for presurgical simulation of microvascular decompression. This study compared the sensitivity and specificity of 1.5- and 3.0-T surface-rendered 3D MR imaging for preoperative identification of the compression vessels of trigeminal neuralgia. One hundred consecutive patients underwent microvascular decompression for trigeminal neuralgia. Forty and 60 patients were evaluated by 1.5- and 3.0-T MR imaging, respectively. Three-dimensional MR images were constructed on the basis of MR imaging, angiography, and venography data and evaluated to determine the compression vessel before surgery. MR imaging findings were compared with the microsurgical findings to compare the sensitivity and specificity of 1.5- and 3.0-T MR imaging. The agreement between MR imaging and surgical findings depended on the compression vessels. For superior cerebellar artery, 1.5- and 3.0-T MR imaging had 84.4% and 82.7% sensitivity and 100% and 100% specificity, respectively. For anterior inferior cerebellar artery, 1.5- and 3.0-T MR imaging had 33.3% and 50% sensitivity and 92.9% and 95% specificity, respectively. For the petrosal vein, 1.5- and 3.0-T MR imaging had 75% and 64.3% sensitivity and 79.2% and 78.1% specificity, respectively. Complete pain relief was obtained in 36 of 40 and 55 of 60 patients undergoing 1.5- and 3.0-T MR imaging, respectively. The present study showed that both 1.5- and 3.0-T MR imaging provided high sensitivity and specificity for preoperative assessment of the compression vessels of trigeminal neuralgia. Preoperative 3D imaging provided very high quality presurgical simulation, resulting in excellent clinical outcomes. Copyright © 2013 Elsevier Inc. All rights reserved.

NaK pool-boiler bench-scale receiver durability test: Test results and materials analysis

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

Andraka, C.E.; Goods, S.H.; Bradshaw, R.W.

1994-06-01

Pool-boiler reflux receivers have been considered as an alternative to heat pipes for the input of concentrated solar energy to Stirling-cycle engines in dish-Stirling electric generation systems. Pool boilers offer simplicity in design and fabrication. The operation of a full-scale pool-boiler receiver has been demonstrated for short periods of time. However, to generate cost-effective electricity, the receiver must operate Without significant maintenance for the entire system life, as much as 20 to 30 years. Long-term liquid-metal boiling stability and materials compatibility with refluxing NaK-78 is not known and must be determined for the pool boiler receiver. No boiling system hasmore » been demonstrated for a significant duration with the current porous boiling enhancement surface and materials. Therefore, it is necessary to simulate the full-scale pool boiler design as much as possible, including flux levels, materials, and operating cycles. On-sun testing is impractical because of the limited test time available. A test vessel was constructed with a porous boiling enhancement surface. The boiling surface consisted of a brazed stainless steel powder with about 50% porosity. The vessel was heated with a quartz lamp array providing about go W/CM2 peak incident thermal flux. The vessel was charged with NaK-78. This allows the elimination of costly electric preheating, both on this test and on fullscale receivers. The vessel was fabricated from Haynes 230 alloy. The vessel operated at 750{degrees}C around the clock, with a 1/2-hour shutdown cycle to ambient every 8 hours. The test completed 7500 hours of lamp-on operation time, and over 1000 startups from ambient. The test was terminated when a small leak in an Inconel 600 thermowell was detected. The test design and data are presented here. Metallurgical analysis of virgin and tested materials has begun, and initial results are also presented.« less

Strain Measurement during Stress Rupture of Composite Over-Wrapped Pressure Vessel with Fiber Bragg Gratings Sensors

NASA Technical Reports Server (NTRS)

Banks, Curtis E.; Grant, Joseph; Russell, Sam; Arnett, Shawn

2008-01-01

Fiber optic Bragg gratings were used to measure strain fields during Stress Rupture (SSM) test of Kevlar Composite Over-Wrapped Pressure Vessels (COPV). The sensors were embedded under the over-wrapped attached to the liner released from the Kevlar and attached to the Kevlar released from the liner. Additional sensors (foil gages and fiber bragg gratings) were surface mounted on the COPY liner.

Radiated noise from commercial ships in the Gulf of Maine: implications for whale/vessel collisions.

PubMed

Allen, J Kaitlyn; Peterson, Michael L; Sharrard, George V; Wright, Dana L; Todd, Sean K

2012-09-01

To understand mysticete acoustic-based detection of ships, radiated noise from high-speed craft, cruise ships, catamarans and fishing vessels was recorded June-September 2009. Calibrated acoustic data (<2500 Hz) from a vertical hydrophone array was combined with ship passage information. A cruise ship had the highest broadband source level, while a fishing vessel had the lowest. Ship noise radiated asymmetrically and varied with depth. Bow null-effect acoustic shadow zones were observed for all ship classes and were correlated with ship-length-to-draft-ratios. These shadow zones may reduce ship detection by near-surface mysticetes.

Towards marine seismological Network: real time small aperture seismic array

NASA Astrophysics Data System (ADS)

Ilinskiy, Dmitry

2017-04-01

Most powerful and dangerous seismic events are generated in underwater subduction zones. Existing seismological networks are based on land seismological stations. Increased demands for accuracy of location, magnitude, rupture process of coming earthquakes and at the same time reduction of data processing time require information from seabed seismic stations located near the earthquake generation area. Marine stations provide important contribution for clarification of the tectonic settings in most active subduction zones of the world. Early warning system for subduction zone area is based on marine seabed array which located near the area of most hazardous seismic zone in the region. Fast track processing for location of the earthquake hypocenter and energy takes place in buoy surface unit. Information about detected and located earthquake reaches the onshore seismological center earlier than the first break waves from the same earthquake will reach the nearest onshore seismological station. Implementation of small aperture array is based on existed and shown a good proven performance and costs effective solutions such as weather moored buoy and self-pop up autonomous seabed seismic nodes. Permanent seabed system for real-time operation has to be installed in deep sea waters far from the coast. Seabed array consists of several self-popup seismological stations which continuously acquire the data, detect the events of certain energy class and send detected event parameters to the surface buoy via acoustic link. Surface buoy unit determine the earthquake location by receiving the event parameters from seabed units and send such information in semi-real time to the onshore seismological center via narrow band satellite link. Upon the request from the cost the system could send wave form of events of certain energy class, bottom seismic station battery status and other environmental parameters. When the battery life of particular seabed unit is close to became empty, the seabed unit is switching into sleep mode and send that information to surface buoy and father to the onshore data center. Then seabed unit can wait for the vessel of opportunity for recovery of seabed unit to sea surface and replacing seabed station to another one with fresh batteries. All collected permanent seismic data by seabed unit could than downloaded for father processing and analysis. In our presentation we will demonstrate the several working prototypes of proposed system such as real time cable broad band seismological station and real time buoy seabed seismological station.

Robust leader-follower formation tracking control of multiple underactuated surface vessels

NASA Astrophysics Data System (ADS)

Peng, Zhou-hua; Wang, Dan; Lan, Wei-yao; Sun, Gang

2012-09-01

This paper is concerned with the formation control problem of multiple underactuated surface vessels moving in a leader-follower formation. The formation is achieved by the follower to track a virtual target defined relative to the leader. A robust adaptive target tracking law is proposed by using neural network and backstepping techniques. The advantage of the proposed control scheme is that the uncertain nonlinear dynamics caused by Coriolis/centripetal forces, nonlinear damping, unmodeled hydrodynamics and disturbances from the environment can be compensated by on line learning. Based on Lyapunov analysis, the proposed controller guarantees the tracking errors converge to a small neighborhood of the origin. Simulation results demonstrate the effectiveness of the control strategy.

Sheet production apparatus for removing a crystalline sheet from the surface of a melt using gas jets located above and below the crystalline sheet

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

Kellerman, Peter L.; Thronson, Gregory D.

In one embodiment, a sheet production apparatus comprises a vessel configured to hold a melt of a material. A cooling plate is disposed proximate the melt and is configured to form a sheet of the material on the melt. A first gas jet is configured to direct a gas toward an edge of the vessel. A sheet of a material is translated horizontally on a surface of the melt and the sheet is removed from the melt. The first gas jet may be directed at the meniscus and may stabilize this meniscus or increase local pressure within the meniscus.

Analytical prediction of the heat transfer from a blood vessel near the skin surface when cooled by a symmetrical cooling strip

NASA Technical Reports Server (NTRS)

Chato, J. C.; Shitzer, A.

1971-01-01

An analytical method was developed to estimate the amount of heat extracted from an artery running close to the skin surface which is cooled in a symmetrical fashion by a cooling strip. The results indicate that the optimum width of a cooling strip is approximately three times the depth to the centerline of the artery. The heat extracted from an artery with such a strip is about 0.9 w/m-C which is too small to affect significantly the temperature of the blood flow through a main blood vessel, such as the carotid artery. The method is applicable to veins as well.

Subduction and Restratification Along an Eddy Edge: The Role of Ekman Dynamics and Submesoscale Processes

NASA Astrophysics Data System (ADS)

Lucas, A.; Sengupta, D.; D'Asaro, E. A.; Nash, J. D.; Shroyer, E.; Mahadevan, A.; Tandon, A.; MacKinnon, J. A.; Pinkel, R.

2016-02-01

The exchange of heat between the atmosphere and ocean depends sensitively on the structure and extent of the oceanic boundary layer. Heat fluxes into and out of the ocean in turn influence atmospheric processes, and, in the northern Indian Ocean, impact the dominant regional weather pattern (the southwest Monsoon). In late 2015, measurements of the physical structure of the oceanic boundary layer were collected from a pair of research vessels and an array of autonomous assets in the Bay of Bengal as part of an India-U.S. scientific collaboration. Repeated CTD casts by a specialized shipboard system to 200m with a repeat rate of <3 min and a lateral spacing of < 200m, as well as near-surface sampling acoustic current profilers, showed how on the edge of an oceanic mesoscale eddy, the interaction of the mesoscale strain field, Ekman dynamics, and nonlinear submesoscale processes acted to subduct relative saline water under a very thin layer of fresher water derived from riverine sources. Our detailed surveys of the front between the overriding thin, fresh layer, and subducting adjacent more saline water demonstrated the important of small-scale physical dynamics to frontal slumping and the resulting re-stratification processes. These processes were strongly 3-dimensional and time-dependent. Such dynamics ultimately influence air-sea interactions by creating strongly stratified and very thin oceanic boundary layers in the Bay of Bengal, and allow the development of strong, persistent subsurface temperature maxima.

Monitoring Floods with NASA's ST6 Autonomous Sciencecraft Experiment: Implications on Planetary Exploration

NASA Technical Reports Server (NTRS)

Ip, Felipe; Dohm, J. M.; Baker, V. R.; Castano, B.; Chien, S.; Cichy, B.; Davies, A. G.; Doggett, T.; Greeley, R.; Sherwood, R.

2005-01-01

NASA's New Millennium Program (NMP) Autonomous Sciencecraft Experiment (ASE) [1-3] has been successfully demonstrated in Earth-orbit. NASA has identified the development of an autonomously operating spacecraft as a necessity for an expanded program of missions exploring the Solar System. The versatile ASE spacecraft command and control, image formation, and science processing software was uploaded to the Earth Observer 1 (EO-1) spacecraft in early 2004 and has been undergoing onboard testing since May 2004 for the near real-time detection of surface modification related to transient geological and hydrological processes such as volcanism [4], ice formation and retreat [5], and flooding [6]. Space autonomy technology developed as part of ASE creates the new capability to autonomously detect, assess, react to, and monitor dynamic events such as flooding. Part of the challenge has been the difficulty to observe flooding in real time at sufficient temporal resolutions; more importantly, it is the large spatial extent of most drainage networks coupled with the size of the data sets necessary to be downlinked from satellites that make it difficult to monitor flooding from space. Below is a description of the algorithms (referred to as ASE Flood water Classifiers) used in tandem with the Hyperion spectrometer instrument on EO-1 to identify flooding and some of the test results.