Sample records for operating proffit approach

  1. Peak Discharge, Flood Profile, Flood Inundation, and Debris Movement Accompanying the Failure of the Upper Reservoir at the Taum Sauk Pump Storage Facility near Lesterville, Missouri

    USGS Publications Warehouse

    Rydlund, Jr., Paul H.

    2006-01-01

    The Taum Sauk pump-storage hydroelectric power plant located in Reynolds County, Missouri, uses turbines that operate as pumps and hydraulic head generated by discharging water from an upper to a lower reservoir to produce electricity. A 55-acre upper reservoir with a 1.5- billion gallon capacity was built on top of Proffit Mountain, approximately 760 feet above the floodplain of the East Fork Black River. At approximately 5:16 am on December 14, 2005, a 680-foot wide section of the upper reservoir embankment failed suddenly, sending water rushing down the western side of Proffit Mountain and emptying into the floodplain of East Fork Black River. Flood waters from the upper reservoir flowed downstream through Johnson's Shut-Ins State Park and into the lower reservoir of the East Fork Black River. Floods such as this present unique challenges and opportunities to analyze and document peak-flow characteristics, flood profiles, inundation extents, and debris movement. On December 16, 2005, Light Detection and Ranging (LiDAR) data were collected and used to support hydraulic analyses, forensic failure analyses, damage extent, and mitigation of future disasters. To evaluate the impact of sedimentation in the lower reservoir, a bathymetric survey conducted on December 22 and 23, 2005, was compared to a previous bathymetric survey conducted in April, 2005. Survey results indicated the maximum reservoir capacity difference of 147 acre-feet existed at a pool elevation of 730 feet. Peak discharge estimates of 289,000 cubic feet per second along Proffit Mountain and 95,000 cubic feet per second along the East Fork Black River were determined through indirect measurement techniques. The magnitude of the embankment failure flood along the East Fork Black River was approximately 4 times greater than the 100-year flood frequency estimate of 21,900 cubic feet per second, and approximately 3 times greater than the 500-year flood frequency estimate of 30,500 cubic feet per second. Dynamic wave unsteady flow models Dam Break (DAMBRK) and Unsteady NETwork (UNET) were used to route the flood wave from the embankment failure breach of the upper reservoir to the spillway of the lower reservoir. Simulated velocities ranged from 20 to 51 feet per second along Proffit Mountain and 12 to 32 feet per second along the East Fork Black River. Simulated arrival time of the flood wave took approximately 5.5 to 6.0 minutes to enter into the floodplain of the East Fork Black River, and roughly 29 minutes to begin filling the lower reservoir. Simulated shear stress values reached as high as 232 pounds per square foot along the slope of Proffit Mountain and 144 pounds per square foot within the Shut-Ins. Flood depths from the embankment failure may have reached greater than 50 feet along Proffit Mountain and as much as 30 to 40 feet along the East Fork Black River. A steady-state model was used to develop 2-, 5-, 10-, 25-, 50-, 100-, and 500-year flood frequency profiles along the East Fork Black River. A similar flood event, hypothetically resulting from a breach of the east embankment above Taum Sauk Creek, was simulated along with the 100- and 500-year flood profiles on Taum Sauk Creek. Estimated extents of flood inundation were developed for each profile. Debris movement was extensive as a result of the flood wave moving down Proffit Mountain and through Johnson's Shut-Ins State Park. A quantitative assessment of debris movement was conducted to benefit rehabilitation efforts within the park. Approximately 180 acres of timber were affected as a result of the embankment failure flood.

  2. Objectification of Orthodontic Treatment Needs: Does the Classification of Malocclusions or a History of Orthodontic Treatment Matter?

    PubMed

    Kozanecka, Anna; Sarul, Michał; Kawala, Beata; Antoszewska-Smith, Joanna

    2016-01-01

    Orthodontic classifications make it possible to give an accurate diagnosis but do not indicate an objective orthodontic treatment need. In order to evaluate the need for treatment, it is necessary to use such indicators as the IOTN. The aim of the study was to find (i) relationships between individual diagnosis and objective recommendations for treatment and (ii) an answer to the question whether and which occlusal anomalies play an important role in the objectification of treatment needs. Two hundred three 18-year-old adolescents (104 girls, 99 boys) were examined. In order to recognize occlusal anomalies, the classifications proposed by Orlik-Grzybowska and Ackerman-Proffit were used. The occlusal anomalies were divided into three categories: belonging to both classifications, typical of OrlikGrzybowska classification and typical of Ackerman-Proffit classification. In order to determine the objective need for orthodontic treatment, the Dental Health Component (DHC) of the IOTN was used. The occurrence of the following malocclusions covered by both classifications, namely abnormal overjet, crossbite and Angle's class, had a statistically significant (p < 0.05) impact on an increase of treatment needs in the subjects (DHC > 3). As for the classification by Orlik-Grzybowska, dental malpositions and canine class significantly affected the need for orthodontic treatment, while in the case of the Ackerman-Proffit scheme, it was asymmetry and crowding. There was no statistically significant correlation between past orthodontic treatment and current orthodontic treatment need. IOTN may be affected by a greater number of occlusal anomalies than it was assumed. Orthodontic treatment received in the past slightly reduces the need for treatment in 18-year-olds.

  3. Hands-On Teaching through a Student Field Project in Applied Geophysics.

    ERIC Educational Resources Information Center

    Klasner, John Samuel; Crockett, Jeffrey Jon; Horton, Kimberly Beth; Poe, Michele Daun; Wollert, Matthew Todd

    1992-01-01

    Describes the Proffit Mountain project, part of a senior-level class in applied geophysics that provides students with hands-on experience in applying principles and techniques learned in class. Students conduct magnetic, gravity, and radiometric studies over a diabase body which intrudes rhyolite at Proffitt Mountain in southeast Missouri.…

  4. CO2 profile retrievals from TCCON spectra

    NASA Astrophysics Data System (ADS)

    Dohe, Susanne; Hase, Frank; Sepúlveda, Eliezer; García, Omaira; Wunch, Debra; Wennberg, Paul; Gómez-Peláez, Angel; Abshire, James B.; Wofsy, Steven C.; Schneider, Matthias; Blumenstock, Thomas

    2014-05-01

    The Total Carbon Column Observing Network (TCCON) is a global network of ground-based Fourier Transform Spectrometers recording direct solar spectra in the near-infrared spectral region. With stringent requirements on the instrumentation, data processing and calibration, accurate and precise column-averaged abundances of CO2, CH4, N2O, HF, CO, H2O, and HDO are retrieved being an essential contribution for the validation of satellite data (e.g. GOSAT, OCO-2) and carbon cycle research (Olsen and Randerson, 2004). However, the determined column-averaged dry air mole fraction (DMF) contains no information about the vertical CO2 profile, due to the use of a simple scaling retrieval within the common TCCON analysis, where the fitting algorithm GFIT (e.g. Yang et al., 2005) is used. In this presentation we will apply a different procedure for calculating trace gas abundances from the measured spectra, the fitting algorithm PROFFIT (Hase et. al., 2004) which has been shown to be in very good accordance with GFIT. PROFFIT additionally offers the ability to perform profile retrievals in which the pressure broadening effect of absorption lines is used to retrieve vertical gas profiles, being of great interest especially for the CO2 modelling community. A new analyzing procedure will be shown and retrieved vertical CO2 profiles of the TCCON sites Izaña (Tenerife, Canary Islands, Spain) and Lamont (Oklahoma, USA) will be presented and compared with simultaneously performed surface in-situ measurements and CO2 profiles from different aircraft campaigns. References: - Hase, F. et al., J.Q.S.R.T. 87, 25-52, 2004. - Olsen, S.C. and Randerson, J.T., J.G.Res., 109, D023012, 2004. - Yang, Z. et al., J.Q.S.R.T., 90, 309-321, 2005.

  5. CO Seasonal Variability and Trend over Paris Megacity Using Ground-Based QualAir FTS and Satellite IASI-MetOp Measurements

    NASA Astrophysics Data System (ADS)

    Te, Yao; Jeseck, Pascal; Hadji-Lazaro, Juliette

    2012-11-01

    In a growing world with more than 7 billion inhabitants and big emerging countries such as China, Brazil and India, emissions of anthropogenic pollutants are increasing continuously. Monitoring and control of atmospheric pollutants in megacities have become a major challenge for scientists and public health authorities in environmental research area. The QualAir platform at University Pierre et Marie Curie (UPMC), is an innovating experimental research platform dedicated to survey urban atmospheric pollution and air quality. A Bruker Optics IFS 125HR Fourier transform spectrometer belonged to the Laboratoire de Physique Moléculaire pour l'Atmosphère et l'Astrophysique (LPMAA), was adapted for ground-based atmospheric measurements. As one of the major instruments of the QualAir platform, this ground-based Fourier transform spectrometer (QualAir FTS) analyses the composition of the urban atmosphere of Paris, which is the third largest European megacity. The continuous monitoring of atmospheric pollutants is essential to improve the understanding of urban air pollution processes. Associated with a sun-tracker, the QualAir remote sensing FTS operates in solar infrared absorption and enables to monitor many trace gases, and to follow up their variability in the Ile-de-France region. Concentrations of atmospheric pollutants are retrieved by the radiative transfer model PROFFIT. These ground-based remote sensing measurements are compared to ground in-situ measurements and to satellite data from IASI-MetOp (Infrared Atmospheric Sounding Interferometer). The remote sensing total column of the carbon monoxide (CO) obtained from January 2009 to June 2012, has a seasonal variability with a maximum in April and a minimum in October. While, after 2008, the mean CO level is quite stable (no significant decrease as before 2008).

  6. Remote sensing of GHG over Paris megacity and Orléans forest using ground-based QualAir FTS and TCCON-Orléans

    NASA Astrophysics Data System (ADS)

    Te, Y.; Jeseck, P.; Da Costa, J.; Deutscher, N. M.; Warneke, T.; Notholt, J.

    2012-04-01

    In a growing world with more than 7 billion inhabitants and big emerging countries such as China, Brazil and India, emissions of anthropogenic pollutants are increasing continuously. Monitoring and control of atmospheric pollutants in megacities have become a major challenge for scientists and public health authorities in environmental research area. The QualAir platform at University Pierre et Marie Curie (UPMC), is an innovating experimental research platform dedicated to survey greenhouse gases (GHGs) and urban air quality. As one of the major instruments of the QualAir platform, the ground-based Fourier transform spectrometer (QualAir FTS, IFS 125HR model) analyses the composition of the urban atmosphere of Paris, which is the third European megacity. The continuous monitoring of atmospheric pollutants is essential to improve the understanding of urban air pollution processes. Associated with a sun-tracker, the QualAir remote sensing FTS operates in solar infrared absorption and enables to monitor many trace gases, and to follow up their variability in the Ile-de-France region. A description of the QualAir FTS will be given. Concentrations of atmospheric GHG, especially CO2 and CH4, are retrieved by the radiative transfer model PROFFIT. Located in the centre of Paris, the QualAir FTS can provide new and complementary urban measurements as compared to unpolluted ground-based stations of existing networks (NDACC and TCCON). The work made by LPMAA to join the TCCON network will also be presented. TCCON-Orléans is a ground-based FTS of the TCCON network located in the forest of Orléans (100 km south of Paris). Preliminary comparisons of GHGs measurements from both sites will be shown. Such ground-based information will help to better characterize regional GHGs, especially regarding anthropogenic emissions and trends.

  7. Stress Induced in Periodontal Ligament under Orthodontic Loading (Part II): A Comparison of Linear Versus Non-Linear Fem Study.

    PubMed

    Hemanth, M; Deoli, Shilpi; Raghuveer, H P; Rani, M S; Hegde, Chatura; Vedavathi, B

    2015-09-01

    Simulation of periodontal ligament (PDL) using non-linear finite element method (FEM) analysis gives better insight into understanding of the biology of tooth movement. The stresses in the PDL were evaluated for intrusion and lingual root torque using non-linear properties. A three-dimensional (3D) FEM model of the maxillary incisors was generated using Solidworks modeling software. Stresses in the PDL were evaluated for intrusive and lingual root torque movements by 3D FEM using ANSYS software. These stresses were compared with linear and non-linear analyses. For intrusive and lingual root torque movements, distribution of stress over the PDL was within the range of optimal stress value as proposed by Lee, but was exceeding the force system given by Proffit as optimum forces for orthodontic tooth movement with linear properties. When same force load was applied in non-linear analysis, stresses were more compared to linear analysis and were beyond the optimal stress range as proposed by Lee for both intrusive and lingual root torque. To get the same stress as linear analysis, iterations were done using non-linear properties and the force level was reduced. This shows that the force level required for non-linear analysis is lesser than that of linear analysis.

  8. Stress Induced in the Periodontal Ligament under Orthodontic Loading (Part I): A Finite Element Method Study Using Linear Analysis.

    PubMed

    Hemanth, M; Deoli, Shilpi; Raghuveer, H P; Rani, M S; Hegde, Chatura; Vedavathi, B

    2015-08-01

    Orthodontic tooth movement is a complex procedure that occurs due to various biomechanical changes in the periodontium. Optimal orthodontic forces yield maximum tooth movement whereas if the forces fall beyond the optimal threshold it can cause deleterious effects. Among various types of tooth movements intrusion and lingual root torque are associated with causing root resoprtion, especially with the incisors. Therefore in this study, the stress patterns in the periodontal ligament (PDL) were evaluated with intrusion and lingual root torque using finite element method (FEM). A three-dimensional (3D) FEM model of the maxillary incisors was generated using SOLIDWORKS modeling software. Stresses in the PDL were evaluated with intrusive and lingual root torque movements by a 3D FEM using ANSYS software using linear stress analysis. It was observed that with the application of intrusive load compressive stresses were distributed at the apex whereas tensile stress was seen at the cervical margin. With the application of lingual root torque maximum compressive stress was distributed at the apex and tensile stress was distributed throughout the PDL. For intrusive and lingual root torque movements stress values over the PDL was within the range of optimal stress value as proposed by Lee, with a given force system by Proffit as optimum forces for orthodontic tooth movement using linear properties.

  9. Stress Induced in the Periodontal Ligament under Orthodontic Loading (Part I): A Finite Element Method Study Using Linear Analysis

    PubMed Central

    Hemanth, M; deoli, Shilpi; Raghuveer, H P; Rani, M S; Hegde, Chatura; Vedavathi, B

    2015-01-01

    Background: Orthodontic tooth movement is a complex procedure that occurs due to various biomechanical changes in the periodontium. Optimal orthodontic forces yield maximum tooth movement whereas if the forces fall beyond the optimal threshold it can cause deleterious effects. Among various types of tooth movements intrusion and lingual root torque are associated with causing root resoprtion, especially with the incisors. Therefore in this study, the stress patterns in the periodontal ligament (PDL) were evaluated with intrusion and lingual root torque using finite element method (FEM). Materials and Methods: A three-dimensional (3D) FEM model of the maxillary incisors was generated using SOLIDWORKS modeling software. Stresses in the PDL were evaluated with intrusive and lingual root torque movements by a 3D FEM using ANSYS software using linear stress analysis. Results: It was observed that with the application of intrusive load compressive stresses were distributed at the apex whereas tensile stress was seen at the cervical margin. With the application of lingual root torque maximum compressive stress was distributed at the apex and tensile stress was distributed throughout the PDL. Conclusion: For intrusive and lingual root torque movements stress values over the PDL was within the range of optimal stress value as proposed by Lee, with a given force system by Proffit as optimum forces for orthodontic tooth movement using linear properties. PMID:26464555

  10. An Analysis of the Stress induced in the Periodontal Ligament during Extrusion and Rotation Movements- Part II: A Comparison of Linear vs Nonlinear FEM Study.

    PubMed

    Hemanth, M; Raghuveer, H P; Rani, M S; Hegde, Chathura; Kabbur, Karthik J; Chaithra, D; Vedavathi, B

    2015-10-01

    Optimal orthodontic forces are those which stimulate tooth movement with minimal biological trauma to the tooth, periodontal ligament (PDL) during and alveolar bone. Among various types of tooth movements, extrusion and rotational movements are seen to be associated with the least amount of root resorption and have not been studied in detail. The mechanical behavior of the PDL is known to be nonlinear elastic and thus a nonlinear simulation of the PDL provides precision to the calculated stress values. Therefore in this study, the stress patterns in the PDL were evaluated with extrusion and rotational movements using the nonlinear finite element method (FEM). A three-dimensional (3D) FEM model of the maxillary incisors was generated using SOLIDWORKS modelling software. Stresses in the PDL were evaluated with extrusive and rotational movements by a 3D FEM using ANSYS software with nonlinear material properties. It was observed that with the application of extrusive load, the tensile stresses were seen at the apex whereas the compressive stress was distributed at the cervical margin. With the application of rotational movements, maximum compressive stress was distributed at the apex and cervical third whereas the tensile stress was distributed on cervical third of the PDL on the lingual surface. For rotational and extrusion movements, stress values over the periodontal ligament was within the range of optimal stress value as proposed by Lee, with a given force system by Proffit as optimum forces for orthodontic tooth movement using nonlinear properties. During rotation there are stresses concentrated at the apex, hence due to the concentration of the compressive forces at the apex a clinician must avoid placing heavy stresses during tooth movement.

  11. A posteriori operation detection in evolving software models

    PubMed Central

    Langer, Philip; Wimmer, Manuel; Brosch, Petra; Herrmannsdörfer, Markus; Seidl, Martina; Wieland, Konrad; Kappel, Gerti

    2013-01-01

    As every software artifact, also software models are subject to continuous evolution. The operations applied between two successive versions of a model are crucial for understanding its evolution. Generic approaches for detecting operations a posteriori identify atomic operations, but neglect composite operations, such as refactorings, which leads to cluttered difference reports. To tackle this limitation, we present an orthogonal extension of existing atomic operation detection approaches for detecting also composite operations. Our approach searches for occurrences of composite operations within a set of detected atomic operations in a post-processing manner. One major benefit is the reuse of specifications available for executing composite operations also for detecting applications of them. We evaluate the accuracy of the approach in a real-world case study and investigate the scalability of our implementation in an experiment. PMID:23471366

  12. Planning in the Continuous Operations Environment of the International Space Station

    NASA Technical Reports Server (NTRS)

    Maxwell, Theresa; Hagopian, Jeff

    1996-01-01

    The continuous operation planning approach developed for the operations planning of the International Space Station (ISS) is reported on. The approach was designed to be a robust and cost-effective method. It separates ISS planning into two planning functions: long-range planning for a fixed length planning horizon which continually moves forward as ISS operations progress, and short-range planning which takes a small segment of the long-range plan and develops a detailed operations schedule. The continuous approach is compared with the incremental approach, the short and long-range planning functions are described, and the benefits and challenges of implementing a continuous operations planning approach for the ISS are summarized.

  13. Nonunitary and unitary approach to Eigenvalue problem of Boson operators and squeezed coherent states

    NASA Technical Reports Server (NTRS)

    Wunsche, A.

    1993-01-01

    The eigenvalue problem of the operator a + zeta(boson creation operator) is solved for arbitrarily complex zeta by applying a nonunitary operator to the vacuum state. This nonunitary approach is compared with the unitary approach leading for the absolute value of zeta less than 1 to squeezed coherent states.

  14. NASA operations: An agency wide approach to reduce cost

    NASA Technical Reports Server (NTRS)

    Squibb, Gael F.

    1996-01-01

    The NASA Space Operations Management Office (SOMO) is presented. The SOMO concept is based on continuing the distributed participation of the various NASA field centers and agencies, while employing consolidated management through a single lead center. The aim is to determine the duplicity and the overlap between the different agencies that independently developed their own operations management approaches in order to enable more cost effective mission operations by providing common services to the NASA programs. The space operations management will be performed in a distributed manner with a greater degree of contractor involvement than in the past. The changes, approaches and anticipated benefits of this approach to operations are discussed.

  15. Orbiter/payload proximity operations: Lateral approach technique

    NASA Technical Reports Server (NTRS)

    Bell, J. A.; Jones, H. L.; Mcadoo, S. F.

    1977-01-01

    The lateral approach is presented for proximity operations associated with the retrieval of free flying payloads. An out of plane final approach emphasizing onboard software support is recommended for all except the latter segment of the final approach in which manual control is considered mandatory. An overall assessment of various candidate proximity operations techniques are made.

  16. Different approaches for centralized and decentralized water system management in multiple decision makers' problems

    NASA Astrophysics Data System (ADS)

    Anghileri, D.; Giuliani, M.; Castelletti, A.

    2012-04-01

    There is a general agreement that one of the most challenging issues related to water system management is the presence of many and often conflicting interests as well as the presence of several and independent decision makers. The traditional approach to multi-objective water systems management is a centralized management, in which an ideal central regulator coordinates the operation of the whole system, exploiting all the available information and balancing all the operating objectives. Although this approach allows to obtain Pareto-optimal solutions representing the maximum achievable benefit, it is based on assumptions which strongly limits its application in real world contexts: 1) top-down management, 2) existence of a central regulation institution, 3) complete information exchange within the system, 4) perfect economic efficiency. A bottom-up decentralized approach seems therefore to be more suitable for real case applications since different reservoir operators may maintain their independence. In this work we tested the consequences of a change in the water management approach moving from a centralized toward a decentralized one. In particular we compared three different cases: the centralized management approach, the independent management approach where each reservoir operator takes the daily release decision maximizing (or minimizing) his operating objective independently from each other, and an intermediate approach, leading to the Nash equilibrium of the associated game, where different reservoir operators try to model the behaviours of the other operators. The three approaches are demonstrated using a test case-study composed of two reservoirs regulated for the minimization of flooding in different locations. The operating policies are computed by solving one single multi-objective optimal control problem, in the centralized management approach; multiple single-objective optimization problems, i.e. one for each operator, in the independent case; using techniques related to game theory for the description of the interaction between the two operators, in the last approach. Computational results shows that the Pareto-optimal control policies obtained in the centralized approach dominate the control policies of both the two cases of decentralized management and that the so called price of anarchy increases moving toward the independent management approach. However, the Nash equilibrium solution seems to be the most promising alternative because it represents a good compromise in maximizing management efficiency without limiting the behaviours of the reservoir operators.

  17. Cleared for the visual approach: Human factor problems in air carrier operations

    NASA Technical Reports Server (NTRS)

    Monan, W. P.

    1983-01-01

    The study described herein, a set of 353 ASRS reports of unique aviation occurrences significantly involving visual approaches was examined to identify hazards and pitfalls embedded in the visual approach procedure and to consider operational practices that might help avoid future mishaps. Analysis of the report set identified nine aspects of the visual approach procedure that appeared to be predisposing conditions for inducing or exacerbating the effects of operational errors by flight crew members or controllers. Predisposing conditions, errors, and operational consequences of the errors are discussed. In a summary, operational policies that might mitigate the problems are examined.

  18. Evolution of Training in NASA's Mission Operations Directorate

    NASA Technical Reports Server (NTRS)

    Hutt, Jason

    2012-01-01

    NASA s Mission Operations Directorate provides all the mission planning, training, and operations support for NASA's human spaceflight missions including the International Space Station (ISS) and its fleet of supporting vehicles. MOD also develops and maintains the facilities necessary to conduct training and operations for those missions including the Mission Control Center, Space Station Training Facility, Space Vehicle Mockup Facility, and Neutral Buoyancy Laboratory. MOD's overarching approach to human spaceflight training is to "train like you fly." This approach means not only trying to replicate the operational environment in training but also to approach training with the same mindset as real operations. When in training, this means using the same approach for executing operations, responding to off-nominal situations, and conducting yourself in the operations environment in the same manner as you would for the real vehicle.

  19. Turbine sizing of a solar thermal power plant

    NASA Technical Reports Server (NTRS)

    Manvi, R.; Fujita, T.

    1979-01-01

    Since the insolation is intermittent, thermal energy storage is necessary to extend the time of power generation with solar heat past sunset. There are two approaches to specifying the size of turbine-generator units depending on the system operation. In the first approach, the turbine operates at its full capacity when operating on direct solar heat, and at reduced capacity when operating on collected heat out of energy storage. In the second approach, the turbine will always operate at a uniform level either on derated energy from the receiver or from energy storage. Both of these approaches have certain advantages and disadvantages. In this paper, a simple analysis is outlined and exercised to compare the performance and economics of these two approaches.

  20. Parametric Optimization of Some Critical Operating System Functions--An Alternative Approach to the Study of Operating Systems Design

    ERIC Educational Resources Information Center

    Sobh, Tarek M.; Tibrewal, Abhilasha

    2006-01-01

    Operating systems theory primarily concentrates on the optimal use of computing resources. This paper presents an alternative approach to teaching and studying operating systems design and concepts by way of parametrically optimizing critical operating system functions. Detailed examples of two critical operating systems functions using the…

  1. Orbiter/payload proximity operations SES Postsim report. Lateral approach and other techniques

    NASA Technical Reports Server (NTRS)

    Olszewski, O.

    1978-01-01

    Various approach and stationkeeping simulations (proximity operations) were conducted in the Shuttle engineering simulator (SES). This simulator is the first to dynamically include the Orbiter reaction control system (RCS) plume effects on a payload being recovered after rendezvous operations. A procedure for braking, using the simultaneous firing of both jets, was evaluated and found very useful for proximity operations. However this procedure is very inefficient in the RCS usage and requires modifications to the digital autopilot (DAP) software. A new final approach, the lateral approach technique (LAT), or the momentum vector proximity approach, was also evaluated in the simulations. The LAT, which included a tailfirst approach for braking, was evaluated successfully with both inertial and gravity stabilized payloads.

  2. Orbital operations study. Volume 2: Interfacing activities analysis. Part 4: Support operations activity group

    NASA Technical Reports Server (NTRS)

    Steinwachs, W. L.; Patrick, J. W.; Galvin, D. M.; Turkel, S. H.

    1972-01-01

    The findings of the support operations activity group of the orbital operations study are presented. Element interfaces, alternate approaches, design concepts, operational procedures, functional requirements, design influences, and approach selection are presented. The following areas are considered: (1) crew transfer, (2) cargo transfer, (3) propellant transfer, (4) attached element operations, and (5) attached element transport.

  3. A new systems engineering approach to streamlined science and mission operations for the Far Ultraviolet Spectroscopic Explorer (FUSE)

    NASA Technical Reports Server (NTRS)

    Butler, Madeline J.; Sonneborn, George; Perkins, Dorothy C.

    1994-01-01

    The Mission Operations and Data Systems Directorate (MO&DSD, Code 500), the Space Sciences Directorate (Code 600), and the Flight Projects Directorate (Code 400) have developed a new approach to combine the science and mission operations for the FUSE mission. FUSE, the last of the Delta-class Explorer missions, will obtain high resolution far ultraviolet spectra (910 - 1220 A) of stellar and extragalactic sources to study the evolution of galaxies and conditions in the early universe. FUSE will be launched in 2000 into a 24-hour highly eccentric orbit. Science operations will be conducted in real time for 16-18 hours per day, in a manner similar to the operations performed today for the International Ultraviolet Explorer. In a radical departure from previous missions, the operations concept combines spacecraft and science operations and data processing functions in a single facility to be housed in the Laboratory for Astronomy and Solar Physics (Code 680). A small missions operations team will provide the spacecraft control, telescope operations and data handling functions in a facility designated as the Science and Mission Operations Center (SMOC). This approach will utilize the Transportable Payload Operations Control Center (TPOCC) architecture for both spacecraft and instrument commanding. Other concepts of integrated operations being developed by the Code 500 Renaissance Project will also be employed for the FUSE SMOC. The primary objective of this approach is to reduce development and mission operations costs. The operations concept, integration of mission and science operations, and extensive use of existing hardware and software tools will decrease both development and operations costs extensively. This paper describes the FUSE operations concept, discusses the systems engineering approach used for its development, and the software, hardware and management tools that will make its implementation feasible.

  4. Using Vision System Technologies for Offset Approaches in Low Visibility Operations

    NASA Technical Reports Server (NTRS)

    Kramer, Lynda J.; Bailey, Randall E.; Ellis, Kyle K.

    2015-01-01

    Flight deck-based vision systems, such as Synthetic Vision Systems (SVS) and Enhanced Flight Vision Systems (EFVS), have the potential to provide additional margins of safety for aircrew performance and enable the implementation of operational improvements for low visibility surface, arrival, and departure operations in the terminal environment with equivalent efficiency to visual operations. Twelve air transport-rated crews participated in a motion-base simulation experiment to evaluate the use of SVS/EFVS in Next Generation Air Transportation System low visibility approach and landing operations at Chicago O'Hare airport. Three monochromatic, collimated head-up display (HUD) concepts (conventional HUD, SVS HUD, and EFVS HUD) and three instrument approach types (straight-in, 3-degree offset, 15-degree offset) were experimentally varied to test the efficacy of the SVS/EFVS HUD concepts for offset approach operations. The findings suggest making offset approaches in low visibility conditions with an EFVS HUD or SVS HUD appear feasible. Regardless of offset approach angle or HUD concept being flown, all approaches had comparable ILS tracking during the instrument segment and were within the lateral confines of the runway with acceptable sink rates during the visual segment of the approach. Keywords: Enhanced Flight Vision Systems; Synthetic Vision Systems; Head-up Display; NextGen

  5. Endoscopic-guided direct endonasal approach for pituitary surgery.

    PubMed

    Badie, B; Nguyen, P; Preston, J K

    2000-02-01

    Submucosal dissection of the nasal septum is often performed as part of the transseptal approach to the sella. To evaluate whether this submucosal dissection is a necessary component of this operation, we compared the morbidity of a direct transmucosal endonasal approach to that of the transseptal approach in patients undergoing pituitary surgery. Forty-one consecutive patients undergoing pituitary surgery from January 1996 to March 1999 were included in this study. The first 21 patients underwent the standard transseptal operation through either a sublabial or columellar incision. The latter 20 patients were operated on through an endoscopically guided, direct endonasal exposure, without any submucosal dissection of the nasal septum. The operative morbidity, the duration of surgery, and the length of hospitalization for each group were compared. The sphenoid sinus exposure obtained through the endonasal route was comparable with the transseptal approach and was adequate for resection of most pituitary tumors. Although the morbidity of the two approaches was similar, patients undergoing the endonasal operation had less postoperative facial pain. Furthermore, the endonasal approach significantly decreased the length of the operation (116 minutes vs. 161 minutes, p = 0.002) and the duration of hospitalization (3.6 vs. 5.1 days, p = 0.003) as compared with the transseptal route. Morbidity of the endonasal approach to the sphenoid sinus is comparable to that of a conventional transseptal approach. By eliminating the submucosal dissection, the endonasal approach reduces postoperative facial discomfort and decreases length of surgery and hospitalization.

  6. Approach to transaction management for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Easton, C. R.; Cressy, Phil; Ohnesorge, T. E.; Hector, Garland

    1990-01-01

    The Space Station Freedom Manned Base (SSFMB) will support the operation of the many payloads that may be located within the pressurized modules or on external attachment points. The transaction management (TM) approach presented provides a set of overlapping features that will assure the effective and safe operation of the SSFMB and provide a schedule that makes potentially hazardous operations safe, allocates resources within the capability of the resource providers, and maintains an environment conducive to the operations planned. This approach provides for targets of opportunity and schedule adjustments that give the operators the flexibility to conduct a vast majority of their operations with no conscious involvement with the TM function.

  7. MID-VASTUS VS MEDIAL PARA-PATELLAR APPROACH IN TOTAL KNEE REPLACEMENT—TIME TO DISCHARGE

    PubMed Central

    Mukherjee, P.; Press, J.; Hockings, M.

    2009-01-01

    Background It has been shown before that when compared with the medial para-patellar approach, the mid-vastus approach for TKR results in less post-operative pain for patients and more rapid recovery of straight leg raise. As far as we are aware the post-operative length of stay of the two groups of patients has not been compared. We postulated that the reduced pain and more rapid recovery of straight leg raise would translate into an earlier, safe, discharge home for the mid-vastus patients compared with those who underwent a traditional medial para-patellar approach. Methods Twenty patients operated on by each of five established knee arthroplasty surgeons were evaluated prospectively with regard to their pre and post-operative range of movement, time to achieve straight leg raise post-operatively and length of post-operative hospital stay. Only one of the surgeons performed the mid-vastus approach, and the measurements were recorded by physiotherapists who were blinded as to the approach used on each patient. Results The results were analysed using a standard statistical software package, and although the mean length of stay was lower for the mid-vastus patients, the difference did not reach a level of significance (p = 0.13). The time taken to achieve straight leg raise post-operatively was significantly less in the mid-vastus group (p<0.001). Conclusion Although this study confirms previous findings that the mid-vastus approach reduces the time taken for patients to achieve straight leg raise, when compared with the medial para-patellar approach, on its own it does not translate into a significantly shorter length of hospital stay. In order to reduce the length of post-operative hospital stay with an accelerated rehabilitation program for TKR, a multi-disciplinary approach is required. Patient expectations, GP support, physiotherapists and nursing staff all have a role to play and the mid-vastus approach, in permitting earlier straight leg raising, significantly contributes to this. PMID:19742080

  8. Some induced intuitionistic fuzzy aggregation operators applied to multi-attribute group decision making

    NASA Astrophysics Data System (ADS)

    Su, Zhi-xin; Xia, Guo-ping; Chen, Ming-yuan

    2011-11-01

    In this paper, we define various induced intuitionistic fuzzy aggregation operators, including induced intuitionistic fuzzy ordered weighted averaging (OWA) operator, induced intuitionistic fuzzy hybrid averaging (I-IFHA) operator, induced interval-valued intuitionistic fuzzy OWA operator, and induced interval-valued intuitionistic fuzzy hybrid averaging (I-IIFHA) operator. We also establish various properties of these operators. And then, an approach based on I-IFHA operator and intuitionistic fuzzy weighted averaging (WA) operator is developed to solve multi-attribute group decision-making (MAGDM) problems. In such problems, attribute weights and the decision makers' (DMs') weights are real numbers and attribute values provided by the DMs are intuitionistic fuzzy numbers (IFNs), and an approach based on I-IIFHA operator and interval-valued intuitionistic fuzzy WA operator is developed to solve MAGDM problems where the attribute values provided by the DMs are interval-valued IFNs. Furthermore, induced intuitionistic fuzzy hybrid geometric operator and induced interval-valued intuitionistic fuzzy hybrid geometric operator are proposed. Finally, a numerical example is presented to illustrate the developed approaches.

  9. Autonomous onboard crew operations: A review and developmental approach

    NASA Technical Reports Server (NTRS)

    Rogers, J. G.

    1982-01-01

    A review of the literature generated by an intercenter mission approach and consolidation team and their contractors was performed to obtain background information on the development of autonomous operations concepts for future space shuttle and space platform missions. The Boeing 757/767 flight management system was examined to determine the relevance for transfer of the developmental approach and technology to the performance of the crew operations function. In specific, the engine indications and crew alerting system was studied to determine the relevance of this display for the performance of crew operations onboard the vehicle. It was concluded that the developmental approach and technology utilized in the aeronautics industry would be appropriate for development of an autonomous operations concept for the space platform.

  10. 77 FR 9163 - Removal of Category IIIa, IIIb, and IIIc Definitions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-16

    ... to Docket Operations at 202-493-2251. Privacy: The FAA will post all comments it receives, without..., and IIIc operations. Category III aircraft operations are precision approach and landing operations... approach and landing with a runway visual range (RVR) below 1000 feet is considered a Category III...

  11. A distributed planning concept for Space Station payload operations

    NASA Technical Reports Server (NTRS)

    Hagopian, Jeff; Maxwell, Theresa; Reed, Tracey

    1994-01-01

    The complex and diverse nature of the payload operations to be performed on the Space Station requires a robust and flexible planning approach. The planning approach for Space Station payload operations must support the phased development of the Space Station, as well as the geographically distributed users of the Space Station. To date, the planning approach for manned operations in space has been one of centralized planning to the n-th degree of detail. This approach, while valid for short duration flights, incurs high operations costs and is not conducive to long duration Space Station operations. The Space Station payload operations planning concept must reduce operations costs, accommodate phased station development, support distributed users, and provide flexibility. One way to meet these objectives is to distribute the planning functions across a hierarchy of payload planning organizations based on their particular needs and expertise. This paper presents a planning concept which satisfies all phases of the development of the Space Station (manned Shuttle flights, unmanned Station operations, and permanent manned operations), and the migration from centralized to distributed planning functions. Identified in this paper are the payload planning functions which can be distributed and the process by which these functions are performed.

  12. Approach to transaction management for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Easton, C. R.; Cressy, Phil; Ohnesorge, T. E.; Hector, Garland

    1989-01-01

    An approach to managing the operations of the Space Station Freedom based on their external effects is described. It is assumed that there is a conflict-free schedule that, if followed, will allow only appropriate operations to occur. The problem is then reduced to that of ensuring that the operations initiated are within the limits allowed by the schedule, or that the external effects of such operations are within those allowed by the schedule. The main features of the currently adopted transaction management approach are discussed.

  13. A Theoretical and Empirical Comparison of Three Approaches to Achievement Testing.

    ERIC Educational Resources Information Center

    Haladyna, Tom; Roid, Gale

    Three approaches to the construction of achievement tests are compared: construct, operational, and empirical. The construct approach is based upon classical test theory and measures an abstract representation of the instructional objectives. The operational approach specifies instructional intent through instructional objectives, facet design,…

  14. Intelligent resources for satellite ground control operations

    NASA Technical Reports Server (NTRS)

    Jones, Patricia M.

    1994-01-01

    This paper describes a cooperative approach to the design of intelligent automation and describes the Mission Operations Cooperative Assistant for NASA Goddard flight operations. The cooperative problem solving approach is being explored currently in the context of providing support for human operator teams and also in the definition of future advanced automation in ground control systems.

  15. An introduction to shuttle/LDEF retrieval operations: The R-bar approach option. [orbital mechanics and braking schedule

    NASA Technical Reports Server (NTRS)

    Hall, W. M.

    1978-01-01

    Simulated orbiter direct approaches during long duration exposure facility (LDEF) retrieval operations reveal that the resultant orbiter jet plume fields can significantly disturb LDEF. An alternate approach technique which utilizes orbital mechanics forces in lieu of jets to brake the final orbiter/LDEF relative motion during the final approach, is described. Topics discussed include: rendezvous operations from the terminal phase initiation burn through braking at some standoff distance from LDEF, pilot and copilot activities, the cockpit instrumentation employed, and a convenient coordinate frame for studying the relative motion between two orbiting bodies. The basic equations of motion for operating on the LDEF radius vector are introduced. Practical considerations of implementing an R-bar approach, namely, orbiter/LDEF relative state uncertainties and orbiter control system limitations are explored. A possible R-bar approach strategy is developed and demonstrated.

  16. Neurosurgical management of anterior meningo-encephaloceles about 60 cases

    PubMed Central

    Rifi, Loubna; Barkat, Amina; El Khamlichi, Abdeslam; Boulaadas, Malek; El Ouahabi, Abdessamad

    2015-01-01

    Anterior meningo-encephaloceles (AME) are congenital malformations characterized by herniation of brain tissue and meninges through a defect in the cranium, in frontal, orbital, nasal and ethmoidal regions. The management of this complex congenital malformation is controversial according to whether use, an intracranial, extra-cranial or combined approach. This is the first largest series published in Africa, in which we present our experience in the operative management of AME; we share our recommendation in technical consideration for surgical approach with review of the literature. All patients beneficed of neuro-radiological investigations including Plan X rays, Spiral Three dimensional CT scan and MRI. Ophthalmologic and maxillo-facial evaluations were done in all the cases. MEA are surgically approached in various ways, mainly on the basis of its location and type, by cranio-facial approach in one-step, or in two stages by intracranial approach followed by facial approach, only by cranial approach or facial approach. The surgical results were evaluated in the follow up on the basis of disappearance of cranio-facial tumefaction with correction of hypertelorism. 60 children with AME were treated in our department between January 1992 and December 2012. The mean age at time of surgery was 14 months (20 days to 18 years) with slight men predominance (28 females/32 males). Cranio-facial team operated 21 patients, 16 were operated in two stages by intracranial approach followed by facial approach, 20 cases beneficed the neurosurgical approach and three only the facial approach Some post operative complications were observed: 2 cases of post operative hydrocephalus underwent shunt; CSF fistulas in three cases cured by spinal drainage, one death due to per operative hypothermia, 3 cases of recurrence how needed second surgery. After mean follow up for 80 months (1 year to 19 years) theses techniques permitted a good cosmetics results in 42 cases, average cosmetics results in 8 cases, poor results in 5 cases and worse cosmetics results in 4 cases, The AME are rare conditions we used the multiples approach first intracranial approach followed by facial approach, but after 1998 we used one-step correction by combined approach, only cranial approach when needed or facial correction. PMID:26448810

  17. Operability score: an innovative tool for quantitative assessment of operability in comparative studies on surgical anatomy.

    PubMed

    Gagliardi, Filippo; Boari, Nicola; Roberti, Fabio; Caputy, Anthony J; Mortini, Pietro

    2014-09-01

    Comparative anatomical studies have proved to be invaluable in the evaluation of advantages and drawbacks of single approaches to access established target areas. Approach-related exposed areas do not necessarily represent useful areas when performing surgical manoeuvres. Accordingly the concept of "operability" has recently been introduced as a qualitative assessment of the ability to execute surgical manoeuvres. The authors propose an innovative model for the quantitative assessment of the operability, defined as "operability score" (OS), which can be effectively and easily applied to comparative studies on surgical anatomy. A microanatomical study was conducted on six cadaveric heads. Morphometric measurements were collected and operability scores in selected target points of the surgical field were calculated. As illustrative example, the operability score was applied to the extradural subtemporal transzygomatic approach (ESTZ). The operability score is effective in grading system of surgical operability, and instruments manipulation capability. It is a useful tool to evaluate, in a single approach, areas that can be exposed, and to quantify how those areas are suitable for surgical manoeuvres. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  18. Operations management approach to hospitals.

    PubMed

    Harvey, J; Duguay, C R

    1988-06-01

    An operations management systems approach can be a useful tool for coordinating and planning in a complex organization. The authors argue for adapting such an approach to health care from the manufacturing industries in order to facilitate strategy formulation, communication and implementation.

  19. Multiple multicontrol unitary operations: Implementation and applications

    NASA Astrophysics Data System (ADS)

    Lin, Qing

    2018-04-01

    The efficient implementation of computational tasks is critical to quantum computations. In quantum circuits, multicontrol unitary operations are important components. Here, we present an extremely efficient and direct approach to multiple multicontrol unitary operations without decomposition to CNOT and single-photon gates. With the proposed approach, the necessary two-photon operations could be reduced from O( n 3) with the traditional decomposition approach to O( n), which will greatly relax the requirements and make large-scale quantum computation feasible. Moreover, we propose the potential application to the ( n- k)-uniform hypergraph state.

  20. Orbital operations study. Volume 2: Interfacing activities analyses. Part 3: Data management activity group

    NASA Technical Reports Server (NTRS)

    Mehrbach, E.; Turkel, S. H.

    1972-01-01

    A summary of the findings of the data management group of the orbital operations study is presented. Element interfaces, alternate approaches, design concepts, operational procedures, functional requirements, design influences, and approach selection are described. The following interfacing activities are considered: (1) communications, (2) rendezvous, (3) stationkeeping, and (4) detached element operations.

  1. Foundations of Effective Influence Operations: A Framework for Enhancing Army Capabilities

    DTIC Science & Technology

    2009-01-01

    interesting approaches we came across in our survey of social science approaches that might be suitable for supporting influence operations. In many...planning, conducting, and assessing the impact of influence operations on attitudes and behaviors. The approach is based on survey instruments that...second to latitude. Influencing Individuals 21 To illustrate, Figure 2.1 presents, in a three-dimensional form, the results from a Galileo survey

  2. Rational-operator-based depth-from-defocus approach to scene reconstruction.

    PubMed

    Li, Ang; Staunton, Richard; Tjahjadi, Tardi

    2013-09-01

    This paper presents a rational-operator-based approach to depth from defocus (DfD) for the reconstruction of three-dimensional scenes from two-dimensional images, which enables fast DfD computation that is independent of scene textures. Two variants of the approach, one using the Gaussian rational operators (ROs) that are based on the Gaussian point spread function (PSF) and the second based on the generalized Gaussian PSF, are considered. A novel DfD correction method is also presented to further improve the performance of the approach. Experimental results are considered for real scenes and show that both approaches outperform existing RO-based methods.

  3. Optical rectenna operation: where Maxwell meets Einstein

    NASA Astrophysics Data System (ADS)

    Joshi, Saumil; Moddel, Garret

    2016-07-01

    Optical rectennas are antenna-coupled diode rectifiers that receive and convert optical-frequency electromagnetic radiation into DC output. The analysis of rectennas is carried out either classically using Maxwell’s wave-like approach, or quantum-mechanically using Einstein’s particle-like approach for electromagnetic radiation. One of the characteristics of classical operation is that multiple photons transfer their energy to individual electrons, whereas in quantum operation each photon transfers its energy to each electron. We analyze the correspondence between the two approaches by comparing rectenna response first to monochromatic illumination obtained using photon-assisted tunnelling theory and classical theory. Applied to broadband rectenna operation, this correspondence provides clues to designing a rectenna solar cell that has the potential to exceed the 44% quantum-limited conversion efficiency. The comparison of operating regimes shows how optical rectenna operation differs from microwave rectenna operation.

  4. Using Vision System Technologies to Enable Operational Improvements for Low Visibility Approach and Landing Operations

    NASA Technical Reports Server (NTRS)

    Kramer, Lynda J.; Ellis, Kyle K. E.; Bailey, Randall E.; Williams, Steven P.; Severance, Kurt; Le Vie, Lisa R.; Comstock, James R.

    2014-01-01

    Flight deck-based vision systems, such as Synthetic and Enhanced Vision System (SEVS) technologies, have the potential to provide additional margins of safety for aircrew performance and enable the implementation of operational improvements for low visibility surface, arrival, and departure operations in the terminal environment with equivalent efficiency to visual operations. To achieve this potential, research is required for effective technology development and implementation based upon human factors design and regulatory guidance. This research supports the introduction and use of Synthetic Vision Systems and Enhanced Flight Vision Systems (SVS/EFVS) as advanced cockpit vision technologies in Next Generation Air Transportation System (NextGen) operations. Twelve air transport-rated crews participated in a motion-base simulation experiment to evaluate the use of SVS/EFVS in NextGen low visibility approach and landing operations. Three monochromatic, collimated head-up display (HUD) concepts (conventional HUD, SVS HUD, and EFVS HUD) and two color head-down primary flight display (PFD) concepts (conventional PFD, SVS PFD) were evaluated in a simulated NextGen Chicago O'Hare terminal environment. Additionally, the instrument approach type (no offset, 3 degree offset, 15 degree offset) was experimentally varied to test the efficacy of the HUD concepts for offset approach operations. The data showed that touchdown landing performance were excellent regardless of SEVS concept or type of offset instrument approach being flown. Subjective assessments of mental workload and situation awareness indicated that making offset approaches in low visibility conditions with an EFVS HUD or SVS HUD may be feasible.

  5. An Approach to Realizing Process Control for Underground Mining Operations of Mobile Machines

    PubMed Central

    Song, Zhen; Schunnesson, Håkan; Rinne, Mikael; Sturgul, John

    2015-01-01

    The excavation and production in underground mines are complicated processes which consist of many different operations. The process of underground mining is considerably constrained by the geometry and geology of the mine. The various mining operations are normally performed in series at each working face. The delay of a single operation will lead to a domino effect, thus delay the starting time for the next process and the completion time of the entire process. This paper presents a new approach to the process control for underground mining operations, e.g. drilling, bolting, mucking. This approach can estimate the working time and its probability for each operation more efficiently and objectively by improving the existing PERT (Program Evaluation and Review Technique) and CPM (Critical Path Method). If the delay of the critical operation (which is on a critical path) inevitably affects the productivity of mined ore, the approach can rapidly assign mucking machines new jobs to increase this amount at a maximum level by using a new mucking algorithm under external constraints. PMID:26062092

  6. An Approach to Realizing Process Control for Underground Mining Operations of Mobile Machines.

    PubMed

    Song, Zhen; Schunnesson, Håkan; Rinne, Mikael; Sturgul, John

    2015-01-01

    The excavation and production in underground mines are complicated processes which consist of many different operations. The process of underground mining is considerably constrained by the geometry and geology of the mine. The various mining operations are normally performed in series at each working face. The delay of a single operation will lead to a domino effect, thus delay the starting time for the next process and the completion time of the entire process. This paper presents a new approach to the process control for underground mining operations, e.g. drilling, bolting, mucking. This approach can estimate the working time and its probability for each operation more efficiently and objectively by improving the existing PERT (Program Evaluation and Review Technique) and CPM (Critical Path Method). If the delay of the critical operation (which is on a critical path) inevitably affects the productivity of mined ore, the approach can rapidly assign mucking machines new jobs to increase this amount at a maximum level by using a new mucking algorithm under external constraints.

  7. A comparison of longitudinal and transverse approaches to ultrasound-guided axillary vein cannulation by experienced operators.

    PubMed

    He, Yi-Zhou; Zhong, Ming; Wu, Wei; Song, Jie-Qiong; Zhu, Du-Ming

    2017-04-01

    The axillary vein is an easily accessible vessel that can be used for ultrasound-guided central vascular access and offers an alternative to the internal jugular and subclavian veins. The objective of this study was to identify which transducer orientation, longitudinal or transverse, is better for imaging the axillary vein with ultrasound. We analyzed 236 patients who had undergone central venous cannulation of axillary vein in this retrospective study. Patients were divided into two groups, the longitudinal approach group (n=120) and transverse approach group (n=116). Recorded the one-attempt success rate, operation time, arterial puncture rate and pneumothorax rate. We perform chest radiography to confirm pneumothorax on all patients. We compared the one-attempt success rate, operation time, arterial puncture rate and pneumothorax rate between the two groups. The two groups were comparable with clinical characters of patients. The overall success rates of the longitudinal group and the transverse group were both 100%. The rate of one-attempt success in the longitudinal approach group is higher than the transverse approach group (91.7% vs. 82.8%, P=0.040). The transverse approach group had shorter operation time than the longitudinal group (184.7±8.1 vs. 287.5±19.6 seconds, P=0.000). The two groups had lower postoperative complications. Arterial puncture occurred in 1 of 120 longitudinal and 2 of 116 transverse attempts and this difference was no significant (P=0.541). No pneumothorax occurred in the two groups. The longitudinal approach during ultrasound-guided axillary vein cannulation is associated with greater one-attempt success rate compared with the transverse approach by experienced operators. The transverse approach has shorter operation time. The two groups have lower postoperative complications and are comparable with pneumothorax and arterial puncture.

  8. Interval from prostate biopsy to radical prostatectomy does not affect immediate operative outcomes for open or minimally invasive approach.

    PubMed

    Park, Bumsoo; Choo, Seol Ho; Jeon, Hwang Gyun; Jeong, Byong Chang; Seo, Seong Il; Jeon, Seong Soo; Lee, Hyun Moo; Choi, Han Yong

    2014-12-01

    Traditionally, urologists recommend an interval of at least 4 weeks after prostate biopsy before radical prostatectomy. The aim of our study was to evaluate whether the interval from prostate biopsy to radical prostatectomy affects immediate operative outcomes, with a focus on differences in surgical approach. The study population of 1,848 radical prostatectomy patients was divided into two groups according to the surgical approach: open or minimally invasive. Open group included perineal and retropubic approach, and minimally invasive group included laparoscopic and robotic approach. The cut-off of the biopsy-to-surgery interval was 4 weeks. Positive surgical margin status, operative time and estimated blood loss were evaluated as endpoint parameters. In the open group, there were significant differences in operative time and estimated blood loss between the <4-week and ≥4-week interval subgroups, but there was no difference in positive margin rate. In the minimally invasive group, there were no differences in the three outcome parameters between the two subgroups. Multivariate analysis revealed that the biopsy-to-surgery interval was not a significant factor affecting immediate operative outcomes in both open and minimally invasive groups, with the exception of the interval ≥4 weeks as a significant factor decreasing operative time in the minimally invasive group. In conclusion, performing open or minimally invasive radical prostatectomy within 4 weeks of prostate biopsy is feasible for both approaches, and is even beneficial for minimally invasive radical prostatectomy to reduce operative time.

  9. Efficient modeling of vector hysteresis using a novel Hopfield neural network implementation of Stoner–Wohlfarth-like operators

    PubMed Central

    Adly, Amr A.; Abd-El-Hafiz, Salwa K.

    2012-01-01

    Incorporation of hysteresis models in electromagnetic analysis approaches is indispensable to accurate field computation in complex magnetic media. Throughout those computations, vector nature and computational efficiency of such models become especially crucial when sophisticated geometries requiring massive sub-region discretization are involved. Recently, an efficient vector Preisach-type hysteresis model constructed from only two scalar models having orthogonally coupled elementary operators has been proposed. This paper presents a novel Hopfield neural network approach for the implementation of Stoner–Wohlfarth-like operators that could lead to a significant enhancement in the computational efficiency of the aforementioned model. Advantages of this approach stem from the non-rectangular nature of these operators that substantially minimizes the number of operators needed to achieve an accurate vector hysteresis model. Details of the proposed approach, its identification and experimental testing are presented in the paper. PMID:25685446

  10. An evaluation of head-up displays in civil transport operations

    NASA Technical Reports Server (NTRS)

    Lauber, J. K.; Bray, R. S.; Scott, B. C.

    1981-01-01

    To determine the advantages and disadvantages of head-up displays (HUD) in civil transport approach and landing operations, an operational evaluation was conducted on the flight simulator for advanced aircraft at Ames. A non-conformal HUD concept which contained raw data and Flight Director command information, and a conformal, flight path HUD concept was designed to permit terminal area maneuvering, intercept, final approach, flare, and landing operations. Twelve B-727 line pilots (Captains) flew a series of precision and non-precision approaches under a variety of environmental and operational conditions, including wind shear, turbulence and low ceilings and visibilities. A preliminary comparison of various system and pilot performance measures as a function of display type (Flight Director HUD, Flight Path HUD, or No HUD) indicates improvements in precision and accuracy of aircraft flight path control when using the HUDs. The results also demonstrated some potentially unique advantages of a flight path HUD during non-precision approaches.

  11. A new generation of real-time DOS technology for mission-oriented system integration and operation

    NASA Technical Reports Server (NTRS)

    Jensen, E. Douglas

    1988-01-01

    Information is given on system integration and operation (SIO) requirements and a new generation of technical approaches for SIO. Real-time, distribution, survivability, and adaptability requirements and technical approaches are covered. An Alpha operating system program management overview is outlined.

  12. 14 CFR 91.1039 - IFR takeoff, approach and landing minimums.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...) For flight planning purposes, if the destination airport does not have a weather reporting facility... TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional... on a program aircraft operating a program flight may begin an instrument approach procedure to an...

  13. 14 CFR 91.1039 - IFR takeoff, approach and landing minimums.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...) For flight planning purposes, if the destination airport does not have a weather reporting facility... TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional... on a program aircraft operating a program flight may begin an instrument approach procedure to an...

  14. 14 CFR 91.1039 - IFR takeoff, approach and landing minimums.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) For flight planning purposes, if the destination airport does not have a weather reporting facility... TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional... on a program aircraft operating a program flight may begin an instrument approach procedure to an...

  15. 14 CFR 91.1039 - IFR takeoff, approach and landing minimums.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...) For flight planning purposes, if the destination airport does not have a weather reporting facility... TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional... on a program aircraft operating a program flight may begin an instrument approach procedure to an...

  16. 14 CFR 91.1039 - IFR takeoff, approach and landing minimums.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...) For flight planning purposes, if the destination airport does not have a weather reporting facility... TRANSPORTATION (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES GENERAL OPERATING AND FLIGHT RULES Fractional... on a program aircraft operating a program flight may begin an instrument approach procedure to an...

  17. Experience with modified aerospace reliability and quality assurance method for wind turbines

    NASA Technical Reports Server (NTRS)

    Klein, W. E.

    1982-01-01

    The SR&QA approach assures that the machine is not hazardous to the public or operating personnel, can operate unattended on a utility grid, demonstrates reliability operation, and helps establish the quality assurance and maintainability requirements for future wind turbine projects. The approach consisted of modified failure modes and effects analysis (FMEA) during the design phase, minimal hardware inspection during parts fabrication, and three simple documents to control activities during machine construction and operation. Five years experience shows that this low cost approach works well enough that it should be considered by others for similar projects.

  18. [External rhinoplasty: a useful approach for a young plastic surgeon].

    PubMed

    Adant, J P; Bluth, F; Fissette, J

    1998-12-01

    Among the frequently performed plastic surgery operations, rhinoplasty is the most difficult to obtain consistently good results. It is very challenging for young plastic surgeons to modify the external appearance of the nose and restore or maintain a good airway. The external approach has alleviated some of the problems due to understanding and learning of the rhinoplasty operation. Actually, open rhinoplasty allows better visualization of anatomical deformities and better manipulation of tissues allowing better integration of nasal anatomy and physiology. This paper reviews a personal series of 82 patients operated via an open approach between October 94 and October 97. During the same period, 24 patients were operated via an endonasal or percutaneous approach (osteotomies). Indications, advantages and disadvantages of the open approach are discussed. The various techniques used in this series are described and then critically analyzed. In open rhinoplasty, our present revision rate is 8.5%. In conclusion, the open approach seems to be useful for young rhinoplastic surgeons.

  19. Flight evaluation of two-segment approaches using area navigation guidance equipment

    NASA Technical Reports Server (NTRS)

    Schwind, G. K.; Morrison, J. A.; Nylen, W. E.; Anderson, E. B.

    1976-01-01

    A two-segment noise abatement approach procedure for use on DC-8-61 aircraft in air carrier service was developed and evaluated. The approach profile and procedures were developed in a flight simulator. Full guidance is provided throughout the approach by a Collins Radio Company three-dimensional area navigation (RNAV) system which was modified to provide the two-segment approach capabilities. Modifications to the basic RNAV software included safety protection logic considered necessary for an operationally acceptable two-segment system. With an aircraft out of revenue service, the system was refined and extensively flight tested, and the profile and procedures were evaluated by representatives of the airlines, airframe manufacturers, the Air Line Pilots Association, and the Federal Aviation Adminstration. The system was determined to be safe and operationally acceptable. It was then placed into scheduled airline service for an evaluation during which 180 approaches were flown by 48 airline pilots. The approach was determined to be compatible with the airline operational environment, although operation of the RNAV system in the existing terminal area air traffic control environment was difficult.

  20. Operator learning effects in teleoperated rendezvous & docking

    NASA Astrophysics Data System (ADS)

    Wilde, M.; Harder, J.; Purschke, R.

    Teleoperation of spacecraft proximity operations and docking requires delicate timing and coordination of spacecraft maneuvers. Experience has shown that human operators show large performance fluctuations in these areas, which are a major factor to be addressed in operator training. In order to allow the quantification of the impact of these human fluctuations on control system performance and the human perception of this performance, a learning curve study was conducted with teleoperated final approach and docking scenarios. Over a period of ten experiment days, three test participants were tasked with repeatedly completing a set of three training scenarios. The scenarios were designed to contain different combinations of the major elements of any final approach and docking situation, and to feature an increasing difficulty level. The individual difficulty levels for the three operators furthermore differed in the level of operator support functions available in their human-machine interfaces. Operator performance in the test scenarios were evaluated in the fields approach success and precision, docking safety, and approach efficiency by a combination of recorded maneuver data and questionnaires. The results show that operator experience and the associated learning curves increase operator performance substantially, regardless of the support system used. The paper also shows that the fluctuations in operator performance and self-perception are substantial between as well as within experiment days, and must be reckoned with in teleoperation system design and mission planning.

  1. Synthesized voice approach callouts for air transport operations

    NASA Technical Reports Server (NTRS)

    Simpson, C. A.

    1980-01-01

    A flight simulation experiment was performed to determine the effectiveness of synthesized voice approach callouts for air transport operations. Flight deck data was first collected on scheduled air carrier operations to describe existing pilot-not-flying callout procedures in the flight context and to document the types and amounts of other auditory cockpit information during different types of air carrier operations. A flight simulation scenario for a wide-body jet transport airline training simulator was developed in collaboration with a major U.S. air carrier and flown by three-man crews of qualified line pilots as part of their normally scheduled recurrent training. Each crew flew half their approaches using the experimental synthesized voice approach callout system (SYNCALL) and the other half using the company pilot-not-flying approach callout procedures (PNF). Airspeed and sink rate performance was better with the SYNCALL system than with the PNF system for non-precision approaches. For the one-engine approach, for which SYNCALL made inappropriate deviation callouts, airspeed performance was worse with SYNCALL than with PNF. Reliability of normal altitude approach callouts was comparable for PNF on the line and in the simulator and for SYNCALL in the simulator.

  2. Early Fixation of Calcaneus Fractures.

    PubMed

    Swords, Michael P; Penny, Phillip

    2017-03-01

    The treatment of calcaneus fractures is controversial. Historically, most operatively treated fractures have been approached with a lateral extensile incision requiring delay in operative treatment until swelling has improved. There is a current trend and interest in small incision approaches allowing, and in some cases requiring, earlier operative fixation. Clinical scenarios amenable to consideration for early fixation are reviewed. The sinus tarsi surgical approach and reduction techniques are outlined in detail. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Simplified Aircraft-Based Paired Approach: Concept Definition and Initial Analysis

    NASA Technical Reports Server (NTRS)

    Johnson, Sally C.; Lohr, Gary W.; McKissick, Burnell T.; Abbott, Terence S.; Geurreiro, Nelson M.; Volk, Paul

    2013-01-01

    Simplified Aircraft-based Parallel Approach (SAPA) is an advanced concept proposed by the Federal Aviation Administration (FAA) to support dependent parallel approach operations to runways with lateral spacing closer than 2500 ft. At the request of the FAA, NASA performed an initial assessment of the potential performance and feasibility of the SAPA concept, including developing and assessing an operational implementation of the concept and conducting a Monte Carlo wake simulation study to examine the longitudinal spacing requirements. The SAPA concept was shown to have significant operational advantages in supporting the pairing of aircraft with dissimilar final approach speeds. The wake simulation study showed that support for dissimilar final approach speeds could be significantly enhanced through the use of a two-phased altitudebased longitudinal positioning requirement, with larger longitudinal positioning allowed for higher altitudes out of ground effect and tighter longitudinal positioning defined for altitudes near and in ground effect. While this assessment is preliminary and there are a number of operational issues still to be examined, it has shown the basic SAPA concept to be technically and operationally feasible.

  4. Comparison of posterior retroperitoneal and transabdominal lateral approaches in robotic adrenalectomy: an analysis of 200 cases.

    PubMed

    Kahramangil, Bora; Berber, Eren

    2018-04-01

    Although numerous studies have been published on robotic adrenalectomy (RA) in the literature, none has done a comparison of posterior retroperitoneal (PR) and transabdominal lateral (TL) approaches. The aim of this study was to compare the outcomes of robotic PR and TL adrenalectomy. This is a retrospective analysis of a prospectively maintained database. Between September 2008 and January 2017, perioperative outcomes of patients undergoing RA through PR and TL approaches were recorded into an IRB-approved database. Clinical and perioperative parameters were compared using Student's t test, Wilcoxon rank-sum test, and χ 2 test. Multivariate regression analysis was performed to determine factors associated with total operative time. 188 patients underwent 200 RAs. 110 patients were operated through TL and 78 patients through PR approach. Overall, conversion rate to open was 2.5% and 90-day morbidity 4.8%. The perioperative outcomes of TL and PR approaches were similar regarding estimated blood loss, rate of conversion to open, length of hospital stay, and 90-day morbidity. PR approach resulted in a shorter mean ± SD total operative time (136.3 ± 38.7 vs. 154.6 ± 48.4 min; p = 0.005) and lower visual analog scale pain score on postoperative day #1 (4.3 ± 2.5 vs. 5.4 ± 2.4; p = 0.001). After excluding tumors larger than 6 cm operated through TL approach, the difference in operative times persisted (136.3 ± 38.7 vs. 153.7 ± 45.7 min; p = 0.009). On multivariate regression analysis, increasing BMI and TL approaches were associated with longer total operative time. This study shows that robotic PR and TL approaches are equally safe and efficacious. With experience, shorter operative time and less postoperative pain can be achieved with PR technique. This supports the preferential utilization of PR approach in high-volume centers with enough experience.

  5. Muscle gap approach under a minimally invasive channel technique for treating long segmental lumbar spinal stenosis

    PubMed Central

    Bin, Yang; De cheng, Wang; wei, Wang Zong; Hui, Li

    2017-01-01

    Abstract This study aimed to compare the efficacy of muscle gap approach under a minimally invasive channel surgical technique with the traditional median approach. In the Orthopedics Department of Traditional Chinese and Western Medicine Hospital, Tongzhou District, Beijing, 68 cases of lumbar spinal canal stenosis underwent surgery using the muscle gap approach under a minimally invasive channel technique and a median approach between September 2013 and February 2016. Both approaches adopted lumbar spinal canal decompression, intervertebral disk removal, cage implantation, and pedicle screw fixation. The operation time, bleeding volume, postoperative drainage volume, and preoperative and postoperative visual analog scale (VAS) score and Japanese Orthopedics Association score (JOA) were compared between the 2 groups. All patients were followed up for more than 1 year. No significant difference between the 2 groups was found with respect to age, gender, surgical segments. No diversity was noted in the operation time, intraoperative bleeding volume, preoperative and 1 month after the operation VAS score, preoperative and 1 month after the operation JOA score, and 6 months after the operation JOA score between 2 groups (P > .05). The amount of postoperative wound drainage (260.90 ± 160 mL vs 447.80 ± 183.60 mL, P < .001) and the VAS score 6 months after the operation (1.71 ± 0.64 vs 2.19 ± 0.87, P = .01) were significantly lower in the muscle gap approach group than in the median approach group (P < .05). In the muscle gap approach under a minimally invasive channel group, the average drainage volume was reduced by 187 mL, and the average VAS score 6 months after the operation was reduced by an average of 0.48. The muscle gap approach under a minimally invasive channel technique is a feasible method to treat long segmental lumbar spinal canal stenosis. It retains the integrity of the posterior spine complex to the greatest extent, so as to reduce the adjacent spinal segmental degeneration and soft tissue trauma. Satisfactory short-term and long-term clinical results were obtained. PMID:28796075

  6. Data Sharing to Improve Close Approach Monitoring and Safety of Flight

    NASA Astrophysics Data System (ADS)

    Chan, Joseph; DalBello, Richard; Hope, Dean; Wauthier, Pascal; Douglas, Tim; Inghram, Travis

    2009-03-01

    Individual satellite operators have done a good job of developing the internal protocols and procedures to ensure the safe operation of their fleets. However, data sharing among operators for close approach monitoring is conducted in an ad-hoc manner during relocations, and there is currently no standardized agreement among operators on the content, format, and distribution protocol for data sharing. Crowding in geostationary orbit, participation by new commercial actors, government interest in satellite constellations, and highly maneuverable spacecraft all suggest that satellite operators will need to begin a dialogue on standard communication protocols and procedure to improve situation awareness. We will give an overview of the current best practices among different operators for close approach monitoring and discuss the concept of an active data center to improve data sharing, conjunction monitoring, and avoidance among satellite operators. We will also report on the progress and lessons learned from a Data Center prototype conducted by several operators over a one year period.

  7. Renaissance architecture for Ground Data Systems

    NASA Technical Reports Server (NTRS)

    Perkins, Dorothy C.; Zeigenfuss, Lawrence B.

    1994-01-01

    The Mission Operations and Data Systems Directorate (MO&DSD) has embarked on a new approach for developing and operating Ground Data Systems (GDS) for flight mission support. This approach is driven by the goals of minimizing cost and maximizing customer satisfaction. Achievement of these goals is realized through the use of a standard set of capabilities which can be modified to meet specific user needs. This approach, which is called the Renaissance architecture, stresses the engineering of integrated systems, based upon workstation/local area network (LAN)/fileserver technology and reusable hardware and software components called 'building blocks.' These building blocks are integrated with mission specific capabilities to build the GDS for each individual mission. The building block approach is key to the reduction of development costs and schedules. Also, the Renaissance approach allows the integration of GDS functions that were previously provided via separate multi-mission facilities. With the Renaissance architecture, the GDS can be developed by the MO&DSD or all, or part, of the GDS can be operated by the user at their facility. Flexibility in operation configuration allows both selection of a cost-effective operations approach and the capability for customizing operations to user needs. Thus the focus of the MO&DSD is shifted from operating systems that we have built to building systems and, optionally, operations as separate services. Renaissance is actually a continuous process. Both the building blocks and the system architecture will evolve as user needs and technology change. Providing GDS on a per user basis enables this continuous refinement of the development process and product and allows the MO&DSD to remain a customer-focused organization. This paper will present the activities and results of the MO&DSD initial efforts toward the establishment of the Renaissance approach for the development of GDS, with a particular focus on both the technical and process implications posed by Renaissance to the MO&DSD.

  8. What is the learning curve for the anterior approach for total hip arthroplasty?

    PubMed

    de Steiger, Richard Noel; Lorimer, Michelle; Solomon, Michael

    2015-12-01

    There are many factors that may affect the learning curve for total hip arthroplasty (THA) and surgical approach is one of these. There has been renewed interest in the direct anterior approach for THA with variable outcomes reported, but few studies have documented a surgeon's individual learning curve when using this approach. (1) What was the revision rate for all surgeons adopting the anterior approach for placement of a particular implant? (2) What was the revision rate for surgeons who performed > 100 cases in this fashion? (3) Is there a minimum number of cases required to complete a learning curve for this procedure? The Australian Orthopaedic Association National Joint Replacement Registry prospectively collects data on all primary and revision joint arthroplasty surgery. We analyzed all conventional THAs performed up to December 31, 2013, with a primary diagnosis of osteoarthritis using a specific implant combination and secondarily those associated with surgeons performing more than 100 procedures. Ninety-five percent of these procedures were performed through the direct anterior approach. Procedures using this combination were ordered from earliest (first procedure date) to latest (last procedure date) for each individual surgeon. Using the order number for each surgeon, five operation groups were defined: one to 15 operations, 16 to 30 operations, 31 to 50 operations, 51 to 100 operations, and > 100 operations. The primary outcome measure was time to first revision using Kaplan-Meier estimates of survivorship. Sixty-eight surgeons performed 5499 THAs using the specified implant combination. The cumulative percent revision at 4 years for all 68 surgeons was 3% (95% confidence interval [CI], 2.5-3.8). For surgeons who had performed over 100 operations, the cumulative revision rate was 3% (95% CI, 2.0-3.5). It was not until surgeons had performed over 50 operations that there was no difference in the cumulative percent revision compared with over 100 operations. The cumulative percent revision for surgeons performing 51 to 100 operations at 4 years was 3% (95% CI, 1.5-5.4) and over 100 operations 2% (95% CI, 1.2-2.7; hazard ratio, 1.40 [95% CI, 0.7-2.7]; p = 0.33). There is a learning curve for the anterior approach for THA even when using a prosthesis combination specifically marketed for that approach. We found that 50 or more procedures need to be performed by a surgeon before the rate of revision is no different from performing 100 or more procedures. Surgeons should be aware of this initial higher rate of revision when deciding which approach delivers the best outcome for their patients.

  9. Integrated Communication in Multinational Coalition Operations Within a Comprehensive Approach. Framework Concept

    DTIC Science & Technology

    2010-10-22

    international crisis management operations. Based on the acknowledgment that coalitions are challenged with achieving both cohesive and coherent...conceptual framework for integrating communication in international crisis management operations. Based on the acknowledgment that coalitions are...CHALLENGE: COHESION AND COHERENCE..................................................... 31 3.3 A MANAGEMENT AND CLIENT-CENTRED APPROACH TO

  10. Operator Factorization and the Solution of Second-Order Linear Ordinary Differential Equations

    ERIC Educational Resources Information Center

    Robin, W.

    2007-01-01

    The theory and application of second-order linear ordinary differential equations is reviewed from the standpoint of the operator factorization approach to the solution of ordinary differential equations (ODE). Using the operator factorization approach, the general second-order linear ODE is solved, exactly, in quadratures and the resulting…

  11. ISS Payload Operations: The Need for and Benefit of Responsive Planning

    NASA Technical Reports Server (NTRS)

    Nahay, Ed; Boster, Mandee

    2000-01-01

    International Space Station (ISS) payload operations are controlled through implementation of a payload operations plan. This plan, which represents the defined approach to payload operations in general, can vary in terms of level of definition. The detailed plan provides the specific sequence and timing of each component of a payload's operations. Such an approach to planning was implemented in the Spacelab program. The responsive plan provides a flexible approach to payload operations through generalization. A responsive approach to planning was implemented in the NASA/Mir Phase 1 program, and was identified as a need during the Skylab program. The current approach to ISS payload operations planning and control tends toward detailed planning, rather than responsive planning. The use of detailed plans provides for the efficient use of limited resources onboard the ISS. It restricts flexibility in payload operations, which is inconsistent with the dynamic nature of the ISS science program, and it restricts crew desires for flexibility and autonomy. Also, detailed planning is manpower intensive. The development and implementation of a responsive plan provides for a more dynamic, more accommodating, and less manpower intensive approach to planning. The science program becomes more dynamic and responsive as the plan provides flexibility to accommodate real-time science accomplishments. Communications limitations and the crew desire for flexibility and autonomy in plan implementation are readily accommodated with responsive planning. Manpower efficiencies are accomplished through a reduction in requirements collection and coordination, plan development, and maintenance. Through examples and assessments, this paper identifies the need to transition from detailed to responsive plans for ISS payload operations. Examples depict specific characteristics of the plans. Assessments identify the following: the means by which responsive plans accommodate the dynamic nature of science programs and the crew desire for flexibility; the means by which responsive plans readily accommodate ISS communications constraints; manpower efficiencies to be achieved through use of responsive plans; and the implications of responsive planning relative to resource utilization efficiency.

  12. Reusable single-port access device shortens operative time and reduces operative costs.

    PubMed

    Shussman, Noam; Kedar, Asaf; Elazary, Ram; Abu Gazala, Mahmoud; Rivkind, Avraham I; Mintz, Yoav

    2014-06-01

    In recent years, single-port laparoscopy (SPL) has become an attractive approach for performing surgical procedures. The pitfalls of this approach are technical and financial. Financial concerns are due to the increased cost of dedicated devices and prolonged operating room time. Our aim was to calculate the cost of SPL using a reusable port and instruments in order to evaluate the cost difference between this approach to SPL using the available disposable ports and standard laparoscopy. We performed 22 laparoscopic procedures via the SPL approach using a reusable single-port access system and reusable laparoscopic instruments. These included 17 cholecystectomies and five other procedures. Operative time, postoperative length of stay (LOS) and complications were prospectively recorded and were compared with similar data from our SPL database. Student's t test was used for statistical analysis. SPL was successfully performed in all cases. Mean operative time for cholecystectomy was 72 min (range 40-116). Postoperative LOS was not changed from our standard protocols and was 1.1 days for cholecystectomy. The postoperative course was within normal limits for all patients and perioperative morbidity was recorded. Both operative time and length of hospital stay were shorter for the 17 patients who underwent cholecystectomy using a reusable port than for the matched previous 17 SPL cholecystectomies we performed (p < 0.001). Prices of disposable SPL instruments and multiport access devices as well as extraction bags from different manufacturers were used to calculate the cost difference. Operating with a reusable port ended up with an average cost savings of US$388 compared with using disposable ports, and US$240 compared with standard laparoscopy. Single-port laparoscopic surgery is a technically challenging and expensive surgical approach. Financial concerns among others have been advocated against this approach; however, we demonstrate herein that using a reusable port and instruments reduces operative time and overall operative costs, even beyond the cost of standard laparoscopy.

  13. An avionics sensitivity study. Volume 1: Operational considerations

    NASA Technical Reports Server (NTRS)

    Scott, R. W.; Mcconkey, E. D.

    1976-01-01

    Equipment and operational concepts affecting aircraft in the terminal area are reported. Curved approach applications and modified climb and descent procedures for minimum fuel consumption are considered. The curved approach study involves the application of MLS guidance to enable execution of the current visual approach to Washington National Airport under instrument flight conditions. The operational significance and the flight path control requirements involved in the application of curved approach paths to this situation are considered. Alternative flight path control regimes are considered to achieve minimum fuel consumption subject to constraints related to air traffic control requirements, flight crew and passenger reactions, and airframe and powerplant limitations.

  14. Application of genetic algorithm in integrated setup planning and operation sequencing

    NASA Astrophysics Data System (ADS)

    Kafashi, Sajad; Shakeri, Mohsen

    2011-01-01

    Process planning is an essential component for linking design and manufacturing process. Setup planning and operation sequencing is two main tasks in process planning. Many researches solved these two problems separately. Considering the fact that the two functions are complementary, it is necessary to integrate them more tightly so that performance of a manufacturing system can be improved economically and competitively. This paper present a generative system and genetic algorithm (GA) approach to process plan the given part. The proposed approach and optimization methodology analyses the TAD (tool approach direction), tolerance relation between features and feature precedence relations to generate all possible setups and operations using workshop resource database. Based on these technological constraints the GA algorithm approach, which adopts the feature-based representation, optimizes the setup plan and sequence of operations using cost indices. Case study show that the developed system can generate satisfactory results in optimizing the setup planning and operation sequencing simultaneously in feasible condition.

  15. [MATCHE: Management Approach to Teaching Consumer and Homemaking Education.] Occupational Strand: Foods and Nutrition. Module II-C-2: Operations and Activities of a Food Service Operation.

    ERIC Educational Resources Information Center

    Waskey, Frank

    This competency-based preservice home economics teacher education module on operations and activities of a food service operation is the second in a set of three modules on occupational education relating to foods and nutrition. (This set is part of a larger series of sixty-seven modules on the Management Approach to Teaching Consumer and…

  16. Going Below Minimums: The Efficacy of Display Enhanced/Synthetic Vision Fusion for Go-Around Decisions during Non-Normal Operations

    NASA Technical Reports Server (NTRS)

    Prinzel, Lawrence J., III; Kramer, Lynda J.; Bailey, Randall E.

    2007-01-01

    The use of enhanced vision systems in civil aircraft is projected to increase rapidly as the Federal Aviation Administration recently changed the aircraft operating rules under Part 91, revising the flight visibility requirements for conducting approach and landing operations. Operators conducting straight-in instrument approach procedures may now operate below the published approach minimums when using an approved enhanced flight vision system that shows the required visual references on the pilot's Head-Up Display. An experiment was conducted to evaluate the complementary use of synthetic vision systems and enhanced vision system technologies, focusing on new techniques for integration and/or fusion of synthetic and enhanced vision technologies and crew resource management while operating under these newly adopted rules. Experimental results specific to flight crew response to non-normal events using the fused synthetic/enhanced vision system are presented.

  17. Using model based systems engineering for the development of the Large Synoptic Survey Telescope's operational plan

    NASA Astrophysics Data System (ADS)

    Selvy, Brian M.; Claver, Charles; Willman, Beth; Petravick, Don; Johnson, Margaret; Reil, Kevin; Marshall, Stuart; Thomas, Sandrine; Lotz, Paul; Schumacher, German; Lim, Kian-Tat; Jenness, Tim; Jacoby, Suzanne; Emmons, Ben; Axelrod, Tim

    2016-08-01

    We† provide an overview of the Model Based Systems Engineering (MBSE) language, tool, and methodology being used in our development of the Operational Plan for Large Synoptic Survey Telescope (LSST) operations. LSST's Systems Engineering (SE) team is using a model-based approach to operational plan development to: 1) capture the topdown stakeholders' needs and functional allocations defining the scope, required tasks, and personnel needed for operations, and 2) capture the bottom-up operations and maintenance activities required to conduct the LSST survey across its distributed operations sites for the full ten year survey duration. To accomplish these complimentary goals and ensure that they result in self-consistent results, we have developed a holistic approach using the Sparx Enterprise Architect modeling tool and Systems Modeling Language (SysML). This approach utilizes SysML Use Cases, Actors, associated relationships, and Activity Diagrams to document and refine all of the major operations and maintenance activities that will be required to successfully operate the observatory and meet stakeholder expectations. We have developed several customized extensions of the SysML language including the creation of a custom stereotyped Use Case element with unique tagged values, as well as unique association connectors and Actor stereotypes. We demonstrate this customized MBSE methodology enables us to define: 1) the rolls each human Actor must take on to successfully carry out the activities associated with the Use Cases; 2) the skills each Actor must possess; 3) the functional allocation of all required stakeholder activities and Use Cases to organizational entities tasked with carrying them out; and 4) the organization structure required to successfully execute the operational survey. Our approach allows for continual refinement utilizing the systems engineering spiral method to expose finer levels of detail as necessary. For example, the bottom-up, Use Case-driven approach will be deployed in the future to develop the detailed work procedures required to successfully execute each operational activity.

  18. Accreditation and quality approach in operating theatre departments: the French approach.

    PubMed

    Soudée, M

    2005-01-01

    Since 1996, French health establishments are subjected to a process of evaluating the quality of care, called "accreditation". This process was controlled by ANAES, which, after January 1st, 2005 became the Haute Autorité de Santé (HAS). The accreditation is characterized by a dual process of self-assessment and external audit, leading to four levels of accreditation. In spite of requiring a time-consuming methodology, this approach provides an important means of consolidating the development of the quality approach and re-stimulating the compliance of establishments with standards of safety and vigilance. The professional teams of many French operating theatre departments have been able to use the regulatory and restricting framework of accreditation to organize quality approaches specific to the operative system, supported by the organizational structures of the department such as the operating suite committee, departmental boards and the steering group. Based on quality guidelines including a commitment from the manager and operating suite committee, as well as a quality flow chart and a quality system, these teams describe the main procedures for running the operating theatre. They also organize the follow-up of incidents and undesirable events, along with the risks and points to watch. Audits of the operative system are planned on a regular basis. The second version of the accreditation process considerably reinforces the assessment of professional practices by evaluating the relevance, the risks and the methods of managing care for pathologies. It will make it possible to implement assessments of the health care provided by operating theatre departments and will reinforce the importance of search for quality.

  19. XV-15 Tiltrotor Low Noise Approach Operations

    NASA Technical Reports Server (NTRS)

    Conner, David A.; Marcolini, Michael A.; Decker, William A.; Cline, John H.; Edwards, Bryan D.; Nicks, Colby O.; Klein, Peter D.

    1999-01-01

    Acoustic data have been acquired for the XV-15 tiltrotor aircraft performing approach operations for a variety of different approach profile configurations. This flight test program was conducted jointly by NASA, the U.S. Army, and Bell Helicopter Textron, Inc. (BHTI) in June 1997. The XV-15 was flown over a large area microphone array, which was deployed to directly measure the noise footprint produced during actual approach operations. The XV-15 flew realistic approach profiles that culminated in IGE hover over a landing pad. Aircraft tracking and pilot guidance was provided by a Differential Global Positioning System (DGPS) and a flight director system developed at BHTI. Approach profile designs emphasized noise reduction while maintaining handling qualities sufficient for tiltrotor commercial passenger ride comfort and flight safety under Instrument Flight Rules (IFR) conditions. A discussion of the approach profile design philosophy is provided. Five different approach profiles are discussed in detail -- 3 deg., 6 deg., and 9 deg. approaches, and two very different 3 deg. to 9 deg. segmented approaches. The approach profile characteristics are discussed in detail, followed by the noise footprints and handling qualities. Sound exposure levels are also presented on an averaged basis and as a function of the sideline distance for a number of up-range distances from the landing point. A comparison of the noise contour areas is also provided. The results document the variation in tiltrotor noise due to changes in operating condition, and indicate the potential for significant noise reduction using the unique tiltrotor capability of nacelle tilt.

  20. Configurational coupled cluster approach with applications to magnetic model systems

    NASA Astrophysics Data System (ADS)

    Wu, Siyuan; Nooijen, Marcel

    2018-05-01

    A general exponential, coupled cluster like, approach is discussed to extract an effective Hamiltonian in configurational space, as a sum of 1-body, 2-body up to n-body operators. The simplest two-body approach is illustrated by calculations on simple magnetic model systems. A key feature of the approach is that equations up to a certain rank do not depend on higher body cluster operators.

  1. Orbital operations study. Volume 2: Interfacing activities analysis. Part 2: Structural and mechanical group

    NASA Technical Reports Server (NTRS)

    Mattson, H. L.; Gianformaggio, A.; Anderson, N. R.

    1972-01-01

    The activities of the structural and mechanical activity group of the orbital operations study project are discussed. Element interfaces, alternate approaches, design concepts, operational procedures, functional requirements, design influences, and approach selection are presented. The following areas are considered: (1) mating, (2) orbital assembly, (3) separation, EOS payload deployment, and EOS payload retraction.

  2. A comparison of longitudinal and transverse approaches to ultrasound-guided axillary vein cannulation by experienced operators

    PubMed Central

    He, Yi-Zhou; Zhong, Ming; Wu, Wei; Song, Jie-Qiong

    2017-01-01

    Background The axillary vein is an easily accessible vessel that can be used for ultrasound-guided central vascular access and offers an alternative to the internal jugular and subclavian veins. The objective of this study was to identify which transducer orientation, longitudinal or transverse, is better for imaging the axillary vein with ultrasound. Methods We analyzed 236 patients who had undergone central venous cannulation of axillary vein in this retrospective study. Patients were divided into two groups, the longitudinal approach group (n=120) and transverse approach group (n=116). Recorded the one-attempt success rate, operation time, arterial puncture rate and pneumothorax rate. We perform chest radiography to confirm pneumothorax on all patients. We compared the one-attempt success rate, operation time, arterial puncture rate and pneumothorax rate between the two groups. Results The two groups were comparable with clinical characters of patients. The overall success rates of the longitudinal group and the transverse group were both 100%. The rate of one-attempt success in the longitudinal approach group is higher than the transverse approach group (91.7% vs. 82.8%, P=0.040). The transverse approach group had shorter operation time than the longitudinal group (184.7±8.1 vs. 287.5±19.6 seconds, P=0.000). The two groups had lower postoperative complications. Arterial puncture occurred in 1 of 120 longitudinal and 2 of 116 transverse attempts and this difference was no significant (P=0.541). No pneumothorax occurred in the two groups. Conclusions The longitudinal approach during ultrasound-guided axillary vein cannulation is associated with greater one-attempt success rate compared with the transverse approach by experienced operators. The transverse approach has shorter operation time. The two groups have lower postoperative complications and are comparable with pneumothorax and arterial puncture. PMID:28523170

  3. Operational Changes in a Shared Resource Laboratory with the Use of a Product Lifecycle Management Approach: A Case Study.

    PubMed

    Hexley, Philip; Smith, Victoria; Wall, Samantha

    2016-04-01

    Shared Resource Laboratories (SRLs) provide investigators access to necessary scientific and resource expertise to leverage complex technologies fully for advancing high-quality biomedical research in a cost-effective manner. At the University of Nebraska Medical Center, the Flow Cytometry Research Facility (FCRF) offered access to exceptional technology, but the methods of operation were outdated and unsustainable. Whereas technology has advanced and the institute has expanded, the operations at the facility remained unchanged for 35 yr. To rectify this, at the end of 2013, we took a product lifecycle management approach to affect large operational changes and align the services offered with the SRL goal of education, as well as to provide service to researchers. These disruptive operational changes took over 10 mo to complete and allowed for independent end-user acquisition of flow cytometry data. The results have been monitored for the past 12 mo. The operational changes have had a positive impact on the quality of research, increased investigator-facility interaction, reduced stress of facility staff, and increased overall use of the resources. This product lifecycle management approach to facility operations allowed us to conceive of, design, implement, and monitor effectively the changes at the FCRF. This approach should be considered by SRL management when faced with the need for operationally disruptive measures.

  4. Securing the human perimeter: beyond operational approaches to developing community capacity to live with fire. Two examples from Victoria, Australia

    Treesearch

    Simone Blair; Matt Campbell; Tom Lowe; Claire Campbell

    2011-01-01

    This paper explores the parallels that frequently exist in fire management organizations between operational approaches to fire and engagement approaches in the community. We observe that community issues are often treated in the same way as a fire incident—"controlled" and "contained" through education and "direct attack"...

  5. Unilateral frontal interhemispheric transfalcial approaches for the removal of olfactory groove meninjiomas.

    PubMed

    Musluman, Ahmet Murat; Yilmaz, Adem; R, Tufan Canseve; Cavusoglu, Halit; Kahyaoglu, Okan; Aydin, Yunus

    2012-01-01

    A unilateral subfrontal interhemispheric transfalcial approach for the removal of olfactory groove meningiomas (OGM) was evaluated in terms of surgical technique, complications, clinical outcomes, and recurrence rate. Twenty-four females and eighteen males with a mean age of 59 years were operated on for OGM within a 12- year (1996-2008) period. The pre- and post-operative Mini-Mental Test (MMT) scores, visual impairment scores (VIS), pre-operative clinical symptoms (headache, epileptic seizure and anosmia), Karnofsky performance scores (KPS), tumor size and tumor extensions were evaluated. The effects of the pre-operative parameters on post-operative MMT, VIS and KPS were investigated. Tumor size and pre-operative MMT significantly affected pre-operative KPS. Mean tumor diameter was 5.6±0.8 cm. Total excision was achieved in 97.6% of all cases. No peri-operative mortality was seen. Ten patients (23.8%) experienced surgery-related complications. The mean follow-up period of cases was 52 months, and the rate of residual tumor re-growth was 2.3%. No parameter showed any effect on post-operative KPS, as no significant difference was seen between pre- and post-operative KPS. A significant positive difference was detected between pre- and post-operative MMT and VIS. A unilateral subfrontal interhemispheric transfalcial approach can be the preferred modality for treating OGM.

  6. Desert Research and Technology Studies (DRATS) 2010 science operations: Operational approaches and lessons learned for managing science during human planetary surface missions

    NASA Astrophysics Data System (ADS)

    Eppler, Dean; Adams, Byron; Archer, Doug; Baiden, Greg; Brown, Adrian; Carey, William; Cohen, Barbara; Condit, Chris; Evans, Cindy; Fortezzo, Corey; Garry, Brent; Graff, Trevor; Gruener, John; Heldmann, Jennifer; Hodges, Kip; Hörz, Friedrich; Hurtado, Jose; Hynek, Brian; Isaacson, Peter; Juranek, Catherine; Klaus, Kurt; Kring, David; Lanza, Nina; Lederer, Susan; Lofgren, Gary; Marinova, Margarita; May, Lisa; Meyer, Jonathan; Ming, Doug; Monteleone, Brian; Morisset, Caroline; Noble, Sarah; Rampe, Elizabeth; Rice, James; Schutt, John; Skinner, James; Tewksbury-Christle, Carolyn M.; Tewksbury, Barbara J.; Vaughan, Alicia; Yingst, Aileen; Young, Kelsey

    2013-10-01

    Desert Research and Technology Studies (Desert RATS) is a multi-year series of hardware and operations tests carried out annually in the high desert of Arizona on the San Francisco Volcanic Field. These activities are designed to exercise planetary surface hardware and operations in conditions where long-distance, multi-day roving is achievable, and they allow NASA to evaluate different mission concepts and approaches in an environment less costly and more forgiving than space. The results from the RATS tests allow selection of potential operational approaches to planetary surface exploration prior to making commitments to specific flight and mission hardware development. In previous RATS operations, the Science Support Room has operated largely in an advisory role, an approach that was driven by the need to provide a loose science mission framework that would underpin the engineering tests. However, the extensive nature of the traverse operations for 2010 expanded the role of the science operations and tested specific operational approaches. Science mission operations approaches from the Apollo and Mars-Phoenix missions were merged to become the baseline for this test. Six days of traverse operations were conducted during each week of the 2-week test, with three traverse days each week conducted with voice and data communications continuously available, and three traverse days conducted with only two 1-hour communications periods per day. Within this framework, the team evaluated integrated science operations management using real-time, tactical science operations to oversee daily crew activities, and strategic level evaluations of science data and daily traverse results during a post-traverse planning shift. During continuous communications, both tactical and strategic teams were employed. On days when communications were reduced to only two communications periods per day, only a strategic team was employed. The Science Operations Team found that, if communications are good and down-linking of science data is ensured, high quality science returns is possible regardless of communications. What is absent from reduced communications is the scientific interaction between the crew on the planet and the scientists on the ground. These scientific interactions were a critical part of the science process and significantly improved mission science return over reduced communications conditions. The test also showed that the quality of science return is not measurable by simple numerical quantities but is, in fact, based on strongly non-quantifiable factors, such as the interactions between the crew and the Science Operations Teams. Although the metric evaluation data suggested some trends, there was not sufficient granularity in the data or specificity in the metrics to allow those trends to be understood on numerical data alone.

  7. Desert Research and Technology Studies (DRATS) 2010 Science Operations: Operational Approaches and Lessons Learned for Managing Science during Human Planetary Surface Missions

    NASA Technical Reports Server (NTRS)

    Eppler, Dean; Adams, Byron; Archer, Doug; Baiden, Greg; Brown, Adrian; Carey, William; Cohen, Barbara; Condit, Chris; Evans, Cindy; Fortezzo, Corey; hide

    2012-01-01

    Desert Research and Technology Studies (Desert RATS) is a multi-year series of hardware and operations tests carried out annually in the high desert of Arizona on the San Francisco Volcanic Field. These activities are designed to exercise planetary surface hardware and operations in conditions where long-distance, multi-day roving is achievable, and they allow NASA to evaluate different mission concepts and approaches in an environment less costly and more forgiving than space.The results from the RATS tests allows election of potential operational approaches to planetary surface exploration prior to making commitments to specific flight and mission hardware development. In previous RATS operations, the Science Support Room has operated largely in an advisory role, an approach that was driven by the need to provide a loose science mission framework that would underpin the engineering tests. However, the extensive nature of the traverse operations for 2010 expanded the role of the science operations and tested specific operational approaches. Science mission operations approaches from the Apollo and Mars-Phoenix missions were merged to become the baseline for this test. Six days of traverse operations were conducted during each week of the 2-week test, with three traverse days each week conducted with voice and data communications continuously available, and three traverse days conducted with only two 1-hour communications periods per day. Within this framework, the team evaluated integrated science operations management using real-time, tactical science operations to oversee daily crew activities, and strategic level evaluations of science data and daily traverse results during a post-traverse planning shift. During continuous communications, both tactical and strategic teams were employed. On days when communications were reduced to only two communications periods per day, only a strategic team was employed. The Science Operations Team found that, if communications are good and down-linking of science data is ensured, high quality science returns is possible regardless of communications. What is absent from reduced communications is the scientific interaction between the crew on the planet and the scientists on the ground. These scientific interactions were a critical part of the science process and significantly improved mission science return over reduced communications conditions. The test also showed that the quality of science return is not measurable by simple numerical quantities but is, in fact, based on strongly non-quantifiable factors, such as the interactions between the crew and the Science Operations Teams. Although the metric evaluation data suggested some trends, there was not sufficient granularity in the data or specificity in the metrics to allow those trends to be understood on numerical data alone.

  8. GHG monitoring over Paris megacity and Orléans forest

    NASA Astrophysics Data System (ADS)

    Te, Y. V.; Jeseck, P.; Zanon, T.; Boursier, C.; Janssen, C.; Deutscher, N. M.; Warneke, T.; Notholt, J.; Lac, C.; Dieudonné, E.; Lopez, M.; Schmidt, M.; Xueref-remy, I. C.

    2012-12-01

    In a growing world with more than 7 billion inhabitants and big emerging countries such as China, Brazil and India, emissions of anthropogenic pollutants and greenhouse gases (GHGs) are increasing continuously. Their monitoring and control in megacities have become a major challenge for scientists and public health authorities in environmental research area. The ground-based Fourier transform spectrometer (QualAir FTS[a], model IFS 125HR) of the QualAir platform located in downtown Paris at University Pierre et Marie Curie (UPMC), is a scientific research instrument dedicated to the survey of greenhouse gases (GHGs) and urban air quality. Equipped with a sun-tracker, the remote sensing QualAir FTS relies on solar infrared absorption for monitoring trace gas concentrations and their variability in the Ile-de-France region[b]. Concentrations of atmospheric GHGs, especially CO2, CH4 and N2O, are retrieved by the radiative transfer model PROFFIT[c]. Because Paris is the third largest European megacity, the QualAir FTS can provide new and complementary measurements as compared to existing ground-based FTS network stations (NDACC and TCCON) located in unpolluted environments, such as the TCCON-Orléans station[d] situated in the forest of Orléans (100 km south of Paris). In the effort to integrate QualAir FTS into the TCCON network, simultaneous FTS measurements of GHGs at Paris and Orléans have been performed. We will emphasize on comparisons of CO2 from these two sites. Our comparison will be completed by high-resolved direct CO2 modeling outputs from the Meso-NH model, and ground in situ measurements at different sites (Orléans/Trainou, Paris/Jussieu, Paris/Eiffel Tower). Parts of the data were acquired in the framework of the French CO2-MEGAPARIS project[e, f], whose main goal is to quantify CO2 emissions from the Paris area. The present data intercomparison will help to reduce uncertainties in carbon cycle models and to better characterize regional GHG fluxes, especially with respect to anthropogenic emission sources (urban versus rural) and trends. References: [a] Té et al., J. Atmos. Oceanic Technol., 29, 911-921, 2012 [b] Té et al., Rev. Sci. Instrum., 81, 103102, 2010 [c] Hase et al., JQSRT, 87, 25-52, 2004 [d] https://tccon-wiki.caltech.edu/Sites/Orleans [e] http://co2-megaparis.lsce.ipsl.fr/ [f] Xueref-Remy et al., Abstract n°A13F-0277, AGU Fall Meeting 2010, San Francisco, USA

  9. Alternatives to the stochastic "noise vector" approach

    NASA Astrophysics Data System (ADS)

    de Forcrand, Philippe; Jäger, Benjamin

    2018-03-01

    Several important observables, like the quark condensate and the Taylor coefficients of the expansion of the QCD pressure with respect to the chemical potential, are based on the trace of the inverse Dirac operator and of its powers. Such traces are traditionally estimated with "noise vectors" sandwiching the operator. We explore alternative approaches based on polynomial approximations of the inverse Dirac operator.

  10. XV-15 Tiltrotor Low Noise Terminal Area Operations

    NASA Technical Reports Server (NTRS)

    Conner, David A.; Marcolini, Michael A.; Edwards, Bryan D.; Brieger, John T.

    1998-01-01

    Acoustic data have been acquired for the XV-15 tiltrotor aircraft performing a variety of terminal area operating procedures. This joint NASA/Bell/Army test program was conducted in two phases. During Phase 1 the XV-15 was flown over a linear array of microphones, deployed perpendicular to the flight path, at a number of fixed operating conditions. This documented the relative noise differences between the various conditions. During Phase 2 the microphone array was deployed over a large area to directly measure the noise footprint produced during realistic approach and departure procedures. The XV-15 flew approach profiles that culminated in IGE hover over a landing pad, then takeoffs from the hover condition back out over the microphone array. Results from Phase 1 identify noise differences between selected operating conditions, while those from Phase 2 identify differences in noise footprints between takeoff and approach conditions and changes in noise footprint due to variation in approach procedures.

  11. Long-term series of tropospheric water vapour amounts and HDO/H2O ratio profiles above Jungfraujoch.

    NASA Astrophysics Data System (ADS)

    Lejeune, B.; Mahieu, E.; Schneider, M.; Hase, F.; Servais, C.; Demoulin, P.

    2012-04-01

    Water vapour is a crucial climate variable involved in many processes which widely determine the energy budget of our planet. In particular, water vapour is the dominant greenhouse gas in the Earth's atmosphere and its radiative forcing is maximum in the middle and upper troposphere. Because of the extremely high variability of water vapour concentration in time and space, it is challenging for the available relevant measurement techniques to provide a consistent data set useful for trend analyses and climate studies. Schneider et al. (2006a) showed that ground-based Fourier Transform Infrared (FTIR) spectroscopy, performed from mountain observatories, allows for the detection of H2O variabilities up to the tropopause. Furthermore, the FTIR measurements allow the retrieval of HDO amounts and therefore the monitoring of HDO/H2O ratio profiles whose variations act as markers for the source and history of the atmospheric water vapour. In the framework of the MUSICA European project (Multi-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water, http://www.imk-asf.kit.edu/english/musica.php), a new approach has been developed and optimized by M. Schneider and F. Hase, using the PROFFIT algorithm, to consistently retrieve tropospheric water vapour profiles from high-resolution ground-based infrared solar spectra and so taking benefit from available long-term data sets of ground-based observations. The retrieval of the water isotopologues is performed on a logarithmic scale from 14 micro-windows located in the 2600-3100 cm-1 region. Other important features of this new retrieval strategy are: a speed dependant Voigt line shape model, a joint temperature profile retrieval and an interspecies constraint for the HDO/H2O profiles. In this contribution, we will combine the quality of the MUSICA strategy and of our observations, which are recorded on a regular basis with FTIR spectrometers, under clear-sky conditions, at the NDACC site (Network for the Detection of Atmospheric Composition Change, http://www.ndacc.org) of the Jungfraujoch International Scientific Station (Swiss Alps, 46.5° N, 8.0° E, 3580m asl). Information content analysis of the retrieved H2O products allows us to produce a long-term trend from 1996 to 2011 for different tropospheric levels. We will compare the annual cycle of tropospheric HDO/H2O ratio profiles with those already produced at other sites (Schneider et al., 2010). We will also focus on the diurnal variability of water vapour to determine a time limit in the inter-comparison of different water vapour measurement techniques. Acknowledgments The University of Liège involvement has primarily been supported by the PRODEX program funded by the Belgian Federal Science Policy Office, Brussels and by the Swiss GAW-CH program. The FRS-FNRS and the Fédération Wallonie-Bruxelles are further acknowledged for observational activities support. We thank the International Foundation High Altitude Research Stations Jungfraujoch and Gornergrat (HFSJG, Bern) for supporting the facilities needed to perform the observations. MUSICA is funded by the European Research Council under the European Community's Seventh Framework Programme (FP7/2007-2013) / ERC Grant agreement n° 256961.

  12. Path planning during combustion mode switch

    DOEpatents

    Jiang, Li; Ravi, Nikhil

    2015-12-29

    Systems and methods are provided for transitioning between a first combustion mode and a second combustion mode in an internal combustion engine. A current operating point of the engine is identified and a target operating point for the internal combustion engine in the second combustion mode is also determined. A predefined optimized transition operating point is selected from memory. While operating in the first combustion mode, one or more engine actuator settings are adjusted to cause the operating point of the internal combustion engine to approach the selected optimized transition operating point. When the engine is operating at the selected optimized transition operating point, the combustion mode is switched from the first combustion mode to the second combustion mode. While operating in the second combustion mode, one or more engine actuator settings are adjusted to cause the operating point of the internal combustion to approach the target operating point.

  13. Enhanced Flight Vision Systems and Synthetic Vision Systems for NextGen Approach and Landing Operations

    NASA Technical Reports Server (NTRS)

    Kramer, Lynda J.; Bailey, Randall E.; Ellis, Kyle K. E.; Williams, Steven P.; Arthur, Jarvis J., III; Prinzel, Lawrence J., III; Shelton, Kevin J.

    2013-01-01

    Synthetic Vision Systems and Enhanced Flight Vision System (SVS/EFVS) technologies have the potential to provide additional margins of safety for aircrew performance and enable operational improvements for low visibility operations in the terminal area environment with equivalent efficiency as visual operations. To meet this potential, research is needed for effective technology development and implementation of regulatory standards and design guidance to support introduction and use of SVS/EFVS advanced cockpit vision technologies in Next Generation Air Transportation System (NextGen) operations. A fixed-base pilot-in-the-loop simulation test was conducted at NASA Langley Research Center that evaluated the use of SVS/EFVS in NextGen low visibility approach and landing operations. Twelve crews flew approach and landing operations in a simulated NextGen Chicago O'Hare environment. Various scenarios tested the potential for using EFVS to conduct approach, landing, and roll-out operations in visibility as low as 1000 feet runway visual range (RVR). Also, SVS was tested to evaluate the potential for lowering decision heights (DH) on certain instrument approach procedures below what can be flown today. Expanding the portion of the visual segment in which EFVS can be used in lieu of natural vision from 100 feet above the touchdown zone elevation to touchdown and rollout in visibilities as low as 1000 feet RVR appears to be viable as touchdown performance was acceptable without any apparent workload penalties. A lower DH of 150 feet and/or possibly reduced visibility minima using SVS appears to be viable when implemented on a Head-Up Display, but the landing data suggests further study for head-down implementations.

  14. Innovative approach to reduction of waste streams for cutting operations in remote environments

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

    Skibo, A.

    SRNL proposes to develop and demonstrate an approach using the SRNL rotary microfilter (RMF) technology for reducing waste streams in remote cutting operations during decontamination operations. SRNL offers to collaborate with Tokyo Electric Power Company (TEPCO) in evaluation, testing, and utilization of SRNL’s radiation-hardened rotary microfilter in the deactivation and decommissioning (D&D) operations of the Fukushima Daiichi Nuclear Power Station (NPS). Refinement of the scope and associated costs will be conducted in consultation with TEPCO.

  15. Arctic and Antarctic Analogs for Planetary Surface Traverses

    NASA Technical Reports Server (NTRS)

    Hoffman, Stephen J.; Cameron, A. O.

    2009-01-01

    The proposed paper summarizes the workshop presentations and discusses several of the key findings or lessons including: (1) A recognition that NASA s current approach for long duration planetary surface operations has fundamental differences from any of the operational approaches described by the invited speakers. These approaches drive the crew size and skill mix to accomplish basic objectives and, in turn, drive the logistical pyramid needed to support these operations. NASA will review the operational approaches of the organizations represented to understand the differentiating factors. NASA will then decide if it should alter its current approach to surface exploration. (2) There are potential parallels between key characteristics of the systems used for exploration in these environments, such as heated volume as an analog for pressurized volume or energy usage for various activities. NASA will look at these characteristics to identify which could help with preliminary planning and gather raw data from the presenters to model these characteristics. (3) New technologies are being applied and design approaches are being tailored to take advantage of these technologies on both side. Interactions between these two communities has begun or is expanding to understand how these new technologies are being leveraged: NASA habitation designers are exchanging ideas and approaches with the Antarctic station designers; Antarctic support

  16. Orbital operations study. Appendix B: Operational procedures

    NASA Technical Reports Server (NTRS)

    Galvin, D. M.; Mattson, H. L.; True, D. M.; Anderson, N. R.; Mehrbach, E.; Gianformaggio, A.; Steinwachs, W. L.; Turkel, S. H.

    1972-01-01

    Operational procedures for each alternate approach for each interfacing activity of the orbital operations study are presented. The applicability of the procedures to interfacing element pairs is identified.

  17. Advancing metropolitan planning for operations : an objectives-driven, performance-based approach : a guidebook

    DOT National Transportation Integrated Search

    2010-02-01

    This guidebook presents an approach for integrating management and operations (M&O) strategies into the metropolitan transportation planning process that is designed to maximize the performance of the existing and planned transportation system. This ...

  18. Transportation Planning with Immune System Derived Approach

    NASA Astrophysics Data System (ADS)

    Sugiyama, Kenji; Yaji, Yasuhito; Ootsuki, John Takuya; Fujimoto, Yasutaka; Sekiguchi, Takashi

    This paper presents an immune system derived approach for planning transportation of materials between manufacturing processes in the factory. Transportation operations are modeled by Petri Net, and divided into submodels. Transportation orders are derived from the firing sequences of those submodels through convergence calculation by the immune system derived excitation and suppression operations. Basic evaluation of this approach is conducted by simulation-based investigation.

  19. STS upper stage operations

    NASA Technical Reports Server (NTRS)

    Kitchens, M. D.; Schnyer, A. D.

    1977-01-01

    Several design/development and operational approaches for STS upper stages are being pursued to realize maximum operational and economic benefits upon the introduction of the STS in the 1980s. The paper focuses special attention on safety operations, launch site operations and on-orbit operations.

  20. Optimizing Dispersed Air Operations: A Concept To Use Highways As Improved Airfields In A Contested Environment

    DTIC Science & Technology

    2015-04-01

    capability to conduct airfield surveys outside of a permissive environment. Optimizing the Rapid Raptor Forward Arming and Refueling Point (FARP...9] An Initial Approach at Dispersing Air Operations: Rapid Raptor Concept ................... [12] Rapid Raptor : Optimized...Approach at Dispersing Air Operations: Rapid Raptor Concept The Air Force Rapid Raptor Fighter Forward Arming and Refueling (FARP) concept is an

  1. Spatial operator algebra for flexible multibody dynamics

    NASA Technical Reports Server (NTRS)

    Jain, A.; Rodriguez, G.

    1993-01-01

    This paper presents an approach to modeling the dynamics of flexible multibody systems such as flexible spacecraft and limber space robotic systems. A large number of degrees of freedom and complex dynamic interactions are typical in these systems. This paper uses spatial operators to develop efficient recursive algorithms for the dynamics of these systems. This approach very efficiently manages complexity by means of a hierarchy of mathematical operations.

  2. Multicriteria Decision-Making Approach with Hesitant Interval-Valued Intuitionistic Fuzzy Sets

    PubMed Central

    Peng, Juan-juan; Wang, Jian-qiang; Wang, Jing; Chen, Xiao-hong

    2014-01-01

    The definition of hesitant interval-valued intuitionistic fuzzy sets (HIVIFSs) is developed based on interval-valued intuitionistic fuzzy sets (IVIFSs) and hesitant fuzzy sets (HFSs). Then, some operations on HIVIFSs are introduced in detail, and their properties are further discussed. In addition, some hesitant interval-valued intuitionistic fuzzy number aggregation operators based on t-conorms and t-norms are proposed, which can be used to aggregate decision-makers' information in multicriteria decision-making (MCDM) problems. Some valuable proposals of these operators are studied. In particular, based on algebraic and Einstein t-conorms and t-norms, some hesitant interval-valued intuitionistic fuzzy algebraic aggregation operators and Einstein aggregation operators can be obtained, respectively. Furthermore, an approach of MCDM problems based on the proposed aggregation operators is given using hesitant interval-valued intuitionistic fuzzy information. Finally, an illustrative example is provided to demonstrate the applicability and effectiveness of the developed approach, and the study is supported by a sensitivity analysis and a comparison analysis. PMID:24983009

  3. Concept of Operations for Interval Management Arrivals and Approach

    NASA Technical Reports Server (NTRS)

    Hicok, Daniel S.; Barmore, Bryan E.

    2016-01-01

    This paper presents the concept of operations for interval management operations to be deployed in the US National Airspace System (NAS) by the Federal Aviation Administration (FAA) Interval Management Program. The arrivals and approach operations are explored in detail including the primary operation and variations. The use of interval management operations is described that begin in en route airspace and continue to a termination point inside the arrival terminal area in the highly automated terminal environment that includes other arrival management tools such as arrival metering, Ground-based Interval Management - Spacing (GIM-S), and Terminal Sequencing and Spacing (TSAS). The roles of Air Traffic and Pilots and the ground automation tools that are used by Air Traffic Controllers to enable the operations are explored.

  4. Rapid Propellant Loading Approach Exploration

    DTIC Science & Technology

    2010-11-01

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

  5. Simultaneous above and below approach to giant pituitary adenomas: surgical strategies and long-term follow-up

    PubMed Central

    D’Ambrosio, Anthony L.; Grobelny, Bartosz T.; Freda, Pamela U.; Wardlaw, Sharon; Bruce, Jeffrey N.

    2012-01-01

    Introduction Giant pituitary adenomas of excessive size, fibrous consistency or unfavorable geometric configuration may be unresectable through conventional operative approaches. We present our select case series for operative resection and long-term follow-up for these unusual tumors, employing both a staged procedure and a combined transsphenoidal-transcranial above and below approach. Method A retrospective chart review was performed on patients operated via the staged, and combined approaches by the senior author (J.N·B.). Pre-operative characteristics and postoperative outcomes were reviewed. A detailed description of the operative technique and perioperative management is provided. Results Between 1993 and 1996, two patients harboring giant pituitary adenomas underwent an intentionally staged resection, and between 1997 and 2006, nine patients harboring giant pituitary adenomas underwent surgery via a single-stage above and below approach. Nine patients (82%) presented with non-secreting adenomas and two patients (18%) presented with prolactinomas refractory to medical management. Gross total resection was achieved in six patients (55%), near total resection in 1 (9%), and subtotal removal in 4 (36%). Seven patients (64%) experienced visual improvement postoperatively and no major complications occurred. Long-term follow-up averaged 51.6 months. Panhypopituitarism was observed in four patients, partial hypopituitarism in four, persistent DI in two, and persistent SIADH in one. Conclusions The addition of a transcranial component to the transsphenoidal approach offers additional visualization of critical neurovascular structures during giant pituitary adenoma resection. Complications rates are similar to other series in which complex pituitary adenomas are resected by other means. The above and below approach is both safe and effective and the immediate and long-term advantages of a single-stage approach justify its utility in this select group of patients. PMID:19242807

  6. Operational test results of the passive final approach spacing tool

    DOT National Transportation Integrated Search

    1997-06-01

    A prototype decision support tool for terminal area air traffic controllers, : referred to as the Final Approach Spacing Tool (FAST), was recently evaluated in : operation with live air traffic at the Dallas/Fort Worth, Texas Airport, : Controllers u...

  7. An Alternative Approach to the Operation of Multinational Reservoir Systems: Application to the Amistad & Falcon System (Lower Rio Grande/Rí-o Bravo)

    NASA Astrophysics Data System (ADS)

    Serrat-Capdevila, A.; Valdes, J. B.

    2005-12-01

    An optimization approach for the operation of international multi-reservoir systems is presented. The approach uses Stochastic Dynamic Programming (SDP) algorithms, both steady-state and real-time, to develop two models. In the first model, the reservoirs and flows of the system are aggregated to yield an equivalent reservoir, and the obtained operating policies are disaggregated using a non-linear optimization procedure for each reservoir and for each nation water balance. In the second model a multi-reservoir approach is applied, disaggregating the releases for each country water share in each reservoir. The non-linear disaggregation algorithm uses SDP-derived operating policies as boundary conditions for a local time-step optimization. Finally, the performance of the different approaches and methods is compared. These models are applied to the Amistad-Falcon International Reservoir System as part of a binational dynamic modeling effort to develop a decision support system tool for a better management of the water resources in the Lower Rio Grande Basin, currently enduring a severe drought.

  8. System approach to automation and robotization of drivage

    NASA Astrophysics Data System (ADS)

    Zinov’ev, VV; Mayorov, AE; Starodubov, AN; Nikolaev, PI

    2018-03-01

    The authors consider the system approach to finding ways of no-man drilling and blasting in the face area by means of automation and robotization of operations with a view to reducing injuries in mines. The analysis is carried out in terms of the drilling and blasting technology applied in Makarevskoe Coal Field, Kuznetsk Coal Basin. Within the system-functional approach and using INDEFO procedure, the processes of drilling and blasthole charging are decomposed into related elementary operations. The automation and robotization methods to avoid the presence of miners in the face are found for each operation.

  9. Bit storage and bit flip operations in an electromechanical oscillator.

    PubMed

    Mahboob, I; Yamaguchi, H

    2008-05-01

    The Parametron was first proposed as a logic-processing system almost 50 years ago. In this approach the two stable phases of an excited harmonic oscillator provide the basis for logic operations. Computer architectures based on LC oscillators were developed for this approach, but high power consumption and difficulties with integration meant that the Parametron was rendered obsolete by the transistor. Here we propose an approach to mechanical logic based on nanoelectromechanical systems that is a variation on the Parametron architecture and, as a first step towards a possible nanomechanical computer, we demonstrate both bit storage and bit flip operations.

  10. On clipping of anterior communicating artery aneurysm via eyebrow-lateral keyhole approach

    PubMed Central

    Wang, Hui; Chen, Chuan; Ye, Zhuo-Peng; Luo, Lun; Li, Wen-Sheng; Guo, Ying

    2015-01-01

    Objective: To evaluate the application of eyebrow-lateral keyhole approach in clipping of anterior communicating artery aneurysm (ACAA) through observing the therapeutic effect of eyebrow-lateral keyhole approach on ACAA. Methods: In 37 patients with ACAA, cisterns were exposed via the eyebrow-lateral keyhole approach to reveal ACAA complex followed by clipping of ACAA. Of the 37 patients, external ventricular drainage was performed on 5 patients before microsurgery. All patients underwent head CT angiography on the second day after operation. Results: Clipping of ACAA was successful in all patients at the first time. In 3 patients, ruptured aneurysm occurred during operation. Three patients underwent ventriculoperitoneal shunt because of postoperative hydrocephalus. Two patients had one-sided anterior cerebral artery infarction after operation. No patient died during operation. Follow-up after the operation indicated that 26 patients returned to normal life and work, 6 patients were able to look after themselves, 4 patients required care in their daily life and one patient died. Conclusion: The eyebrow-lateral keyhole approach is a preferred choice for surgical treatment of ACAA because it can cope with brain swelling and intraoperative ruptured aneurysm. However, it has a certain range of application, so we must strictly follow its indications. PMID:26885043

  11. Robotics in surgery: is a robot necessary? For what?

    PubMed

    Ross, Sharona B; Downs, Darrell; Saeed, Sabrina M; Dolce, John K; Rosemurgy, Alexander S

    2017-02-01

    Every operation can be categorized along a spectrum from "most invasive" to "least invasive", based on the approach(es) through which it is commonly undertaken. Operations that are considered "most invasive" are characterized by "open" approaches with a relatively high degree of morbidity, while operations that are considered "least invasive" are undertaken with minimally invasive techniques and are associated with relatively improved patient outcomes, including faster recovery times and fewer complications. Because of the potential for reduced morbidity, movement along the spectrum towards minimally invasive surgery (MIS) is associated with a host of salutary benefits and, as well, lower costs of patient care. Accordingly, the goal of all stakeholders in surgery should be to attain universal application of the most minimally invasive approaches. Yet the difficulty of performing minimally invasive operations has largely limited its widespread application in surgery, particularly in the context of complex operations (i.e., those requiring complex extirpation and/or reconstruction). Robotic surgery, however, may facilitate application of minimally invasive techniques requisite for particular operations. Enhancements in visualization and dexterity offered by robotic surgical systems allow busy surgeons to quickly gain proficiency in demanding techniques (e.g., pancreaticojejunostomy), within a short learning curve. That is not to say, however, that all operations undertaken with minimally invasive techniques require robotic technology. Herein, we attempt to define how surgeon skill, operative difficulty, patient outcomes, and cost factors determine when robotic technology should be reasonably applied to patient care in surgery.

  12. Time and frequency domain characteristics of detrending-operation-based scaling analysis: Exact DFA and DMA frequency responses

    NASA Astrophysics Data System (ADS)

    Kiyono, Ken; Tsujimoto, Yutaka

    2016-07-01

    We develop a general framework to study the time and frequency domain characteristics of detrending-operation-based scaling analysis methods, such as detrended fluctuation analysis (DFA) and detrending moving average (DMA) analysis. In this framework, using either the time or frequency domain approach, the frequency responses of detrending operations are calculated analytically. Although the frequency domain approach based on conventional linear analysis techniques is only applicable to linear detrending operations, the time domain approach presented here is applicable to both linear and nonlinear detrending operations. Furthermore, using the relationship between the time and frequency domain representations of the frequency responses, the frequency domain characteristics of nonlinear detrending operations can be obtained. Based on the calculated frequency responses, it is possible to establish a direct connection between the root-mean-square deviation of the detrending-operation-based scaling analysis and the power spectrum for linear stochastic processes. Here, by applying our methods to DFA and DMA, including higher-order cases, exact frequency responses are calculated. In addition, we analytically investigate the cutoff frequencies of DFA and DMA detrending operations and show that these frequencies are not optimally adjusted to coincide with the corresponding time scale.

  13. Time and frequency domain characteristics of detrending-operation-based scaling analysis: Exact DFA and DMA frequency responses.

    PubMed

    Kiyono, Ken; Tsujimoto, Yutaka

    2016-07-01

    We develop a general framework to study the time and frequency domain characteristics of detrending-operation-based scaling analysis methods, such as detrended fluctuation analysis (DFA) and detrending moving average (DMA) analysis. In this framework, using either the time or frequency domain approach, the frequency responses of detrending operations are calculated analytically. Although the frequency domain approach based on conventional linear analysis techniques is only applicable to linear detrending operations, the time domain approach presented here is applicable to both linear and nonlinear detrending operations. Furthermore, using the relationship between the time and frequency domain representations of the frequency responses, the frequency domain characteristics of nonlinear detrending operations can be obtained. Based on the calculated frequency responses, it is possible to establish a direct connection between the root-mean-square deviation of the detrending-operation-based scaling analysis and the power spectrum for linear stochastic processes. Here, by applying our methods to DFA and DMA, including higher-order cases, exact frequency responses are calculated. In addition, we analytically investigate the cutoff frequencies of DFA and DMA detrending operations and show that these frequencies are not optimally adjusted to coincide with the corresponding time scale.

  14. Comparative Analysis of Combined (First Anterior, Then Posterior) Versus Only Posterior Approach for Treating Severe Scoliosis

    PubMed Central

    Hero, Nikša; Vengust, Rok; Topolovec, Matevž

    2017-01-01

    Study Design. A retrospective, one center, institutional review board approved study. Objective. Two methods of operative treatments were compared in order to evaluate whether a two-stage approach is justified for correction of bigger idiopathic scoliosis curves. Two stage surgery, combined anterior approach in first operation and posterior instrumentation and correction in the second operation. One stage surgery included only posterior instrumentation and correction. Summary of Background Data. Studies comparing two-stage approach and only posterior approach are rather scarce, with shorter follow up and lack of clinical data. Methods. Three hundred forty eight patients with idiopathic scoliosis were operated using Cotrel–Dubousset (CD) hybrid instrumentation with pedicle screw and hooks. Only patients with curvatures more than or equal to 61° were analyzed and divided in two groups: two stage surgery (N = 30) and one stage surgery (N = 46). The radiographic parameters as well as duration of operation, hospitalization time, and number of segments included in fusion and clinical outcome were analyzed. Results. No statistically significant difference was observed in correction between two-stage group (average correction 69%) and only posterior approach group (average correction 66%). However, there were statistically significant differences regarding hospitalization time, duration of the surgery, and the number of instrumented segments. Conclusion. Two-stage surgery has only a limited advantage in terms of postoperative correction angle compared with the posterior approach. Posterior instrumentation and correction is satisfactory, especially taking into account that the patient is subjected to only one surgery. Level of Evidence: 3 PMID:28125525

  15. Comprehensive approach to image-guided surgery

    NASA Astrophysics Data System (ADS)

    Peters, Terence M.; Comeau, Roch M.; Kasrai, Reza; St. Jean, Philippe; Clonda, Diego; Sinasac, M.; Audette, Michel A.; Fenster, Aaron

    1998-06-01

    Image-guided surgery has evolved over the past 15 years from stereotactic planning, where the surgeon planned approaches to intracranial targets on the basis of 2D images presented on a simple workstation, to the use of sophisticated multi- modality 3D image integration in the operating room, with guidance being provided by mechanically, optically or electro-magnetically tracked probes or microscopes. In addition, sophisticated procedures such as thalamotomies and pallidotomies to relieve the symptoms of Parkinson's disease, are performed with the aid of volumetric atlases integrated with the 3D image data. Operations that are performed stereotactically, that is to say via a small burr- hole in the skull, are able to assume that the information contained in the pre-operative imaging study, accurately represents the brain morphology during the surgical procedure. On the other hand, preforming a procedure via an open craniotomy presents a problem. Not only does tissue shift when the operation begins, even the act of opening the skull can cause significant shift of the brain tissue due to the relief of intra-cranial pressure, or the effect of drugs. Means of tracking and correcting such shifts from an important part of the work in the field of image-guided surgery today. One approach has ben through the development of intra-operative MRI imaging systems. We describe an alternative approach which integrates intra-operative ultrasound with pre-operative MRI to track such changes in tissue morphology.

  16. [Application of individually designed trans-fissure approach in brain surgery: analysis of 90 cases].

    PubMed

    Zhao, Ji-Zong; Wang, Shuo; Zhang, Mao-Zhi; Wang, Lei; Wang, Rong; Tang, Ya-Juan

    2009-01-06

    To explore the feasibility and value of trans-fissure approaches in brain surgery through individually designed craniotomy. Ninety patients with intracranial space-occupying lesions, 47 males and 58 females, aged (43 +/- 14) (1 - 68), were treated by individualized trans-fissure approach surgeries. Linear scalp incision or "horseshoe shape" scalp incision were designed to perform the operation, with a bone flap 3 - 4 cm in diameter. The shortest approach to reach the lesion was decided under the guidance of neuro-navigation and real-time B-mode ultrasonography. Then the lesions were removed through natural cortical fissures. Another 79 patients with intracranial space-occupying lesions, 53 males and 51 females, aged (42 +/- 11) (15 -73), undergoing classical surgeries in the same period were used as control group. The average operation time, size of bone flap, amount of blood loss, hospitalization time, and hospitalization cost were compared between these 2 groups. The operation time of the individually designed trans-fissure approach group was (3.1 +/- 1.6) hours (1.33 - 10.83 hours), significantly shorter than that of the control group [(4.8 +/- 1.9) hrs, P < 0.05]. The amount of blood loss of the individually designed trans-fissure approach group was (173 +/- 168) ml (20 m - 500 ml), significantly less than that of the control group [(410 +/- 61) ml, P < 0.01]. The size of bone flap of the individually designed trans-fissure approach group was (12 +/- 5) cm2 [(1 - 25) cm2], significantly smaller than that of the control group [(20. +/- 9) cm2, P < 0.01]. Four of the 90 patients of the individually designed trans-fissure approach group received retransfusion, compared to 15 in the control group, during operation. No infection or other significant complications occurred after operation in the individually designed trans-fissure approach group. The hospitalization time of the individually designed trans-fissure approach group was (20 +/- 6) days (9 - 39 days), significantly shorter than that of the control group [(24 +/- 7) days, P < 0.01]. The average hospitalization cost of the individually designed trans-fissure approach group was (23171 +/- 7280) yuan RMB; significantly lower than that of the control group [(28096 +/- 10822) yuan, P < 0.01]. One of the land markers of minimally invasive neurosurgery, individualized trans-fissure approach has been proved to be an effective minimally invasive approach that leads to better outcome and fewer complications after operation.

  17. A New Approach to an Old Order.

    ERIC Educational Resources Information Center

    Rambhia, Sanjay

    2002-01-01

    Explains the difficulties middle school students face in algebra regarding the order of operations. Describes a more visual approach to teaching the order of operations so that students can better solve complex problems and be better prepared for the rigors of algebra. (YDS)

  18. Illicit Trafficking in the Western Hemisphere: Developing an Operational Approach to Defeat Smuggling within the Region

    DTIC Science & Technology

    2017-03-31

    and political stability. The threat is currently so pervasive that solving it is impossible without significant strategic reframing. A design ...approach will offer a better understanding of the functions and systems used for illicit trafficking. An operational design will be useful for developing a...illicit drugs, human trafficking, USSOUTHCOM, trafficking, operational design 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT

  19. Achieving Lights-Out Operation of SMAP Using Ground Data System Automation

    NASA Technical Reports Server (NTRS)

    Sanders, Antonio

    2013-01-01

    The approach used in the SMAP ground data system to provide reliable, automated capabilities to conduct unattended operations has been presented. The impacts of automation on the ground data system architecture were discussed, including the three major automation patterns identified for SMAP and how these patterns address the operations use cases. The architecture and approaches used by SMAP will set the baseline for future JPL Earth Science missions.

  20. Group theoretical approach to the Dirac operator on S 2

    NASA Astrophysics Data System (ADS)

    Gutiérrez, Sergio; Huet, Idrish

    2018-04-01

    In this revision we outline the group theoretical approach to formulate and solve the eigenvalue problem of the Dirac operator on the round 2-sphere conceived as the right coset S 2 = SU(2)/U(1). Starting from general symmetry considerations we illustrate the formulation of the Dirac operator through left action or right action differential operators, whose properties on a right coset are quite different. The construction of the spinor space and the solution of the spectral problem using group theoretical methods is also presented.

  1. Analysis of remote operating systems for space-based servicing operations, volume 1

    NASA Technical Reports Server (NTRS)

    1985-01-01

    A two phase study was conducted to analyze and develop the requirements for remote operating systems as applied to space based operations for the servicing, maintenance, and repair of satellites. Phase one consisted of the development of servicing requirements to establish design criteria for remote operating systems. Phase two defined preferred system concepts and development plans which met the requirements established in phase one. The specific tasks in phase two were to: (1) identify desirable operational and conceptual approaches for selected mission scenarios; (2) examine the potential impact of remote operating systems incorporated into the design of the space station; (3) address remote operating systems design issues, such as mobility, which are effected by the space station configuration; and (4) define the programmatic approaches for technology development, testing, simulation, and flight demonstration.

  2. An innovative approach to capability-based emergency operations planning

    PubMed Central

    Keim, Mark E

    2013-01-01

    This paper describes the innovative use information technology for assisting disaster planners with an easily-accessible method for writing and improving evidence-based emergency operations plans. This process is used to identify all key objectives of the emergency response according to capabilities of the institution, community or society. The approach then uses a standardized, objective-based format, along with a consensus-based method for drafting capability-based operational-level plans. This information is then integrated within a relational database to allow for ease of access and enhanced functionality to search, sort and filter and emergency operations plan according to user need and technological capacity. This integrated approach is offered as an effective option for integrating best practices of planning with the efficiency, scalability and flexibility of modern information and communication technology. PMID:28228987

  3. An innovative approach to capability-based emergency operations planning.

    PubMed

    Keim, Mark E

    2013-01-01

    This paper describes the innovative use information technology for assisting disaster planners with an easily-accessible method for writing and improving evidence-based emergency operations plans. This process is used to identify all key objectives of the emergency response according to capabilities of the institution, community or society. The approach then uses a standardized, objective-based format, along with a consensus-based method for drafting capability-based operational-level plans. This information is then integrated within a relational database to allow for ease of access and enhanced functionality to search, sort and filter and emergency operations plan according to user need and technological capacity. This integrated approach is offered as an effective option for integrating best practices of planning with the efficiency, scalability and flexibility of modern information and communication technology.

  4. A Systematic Approach for Engagement Analysis Under Multitasking Environments

    NASA Technical Reports Server (NTRS)

    Zhang, Guangfan; Leddo, John; Xu, Roger; Richey, Carl; Schnell, Tom; McKenzie, Frederick; Li, Jiang

    2011-01-01

    An overload condition can lead to high stress for an operator and further cause substantial drops in performance. On the other extreme, in automated systems, an operator may become underloaded; in which case, it is difficult for the operator to maintain sustained attention. When an unexpected event occurs, either internal or external to the automated system, a disengaged operation may neglect, misunderstand, or respond slowly/inappropriately to the situation. In this paper, we discuss a systematic approach monitor for extremes of cognitive workload and engagement in multitasking environments. Inferences of cognitive workload ar engagement are based on subjective evaluations, objective performance measures, physiological signals, and task analysis results. The systematic approach developed In this paper aggregates these types of information collected under the multitasking environment and can provide a real-time assessment or engagement.

  5. NASA Conjunction Assessment Organizational Approach and the Associated Determination of Screening Volume Sizes

    NASA Technical Reports Server (NTRS)

    Newman, Lauri K.; Hejduk, Matthew D.

    2015-01-01

    NASA is committed to safety of flight for all of its operational assets Performed by CARA at NASA GSFC for robotic satellites Focus of this briefing Performed by TOPO at NASA JSC for human spaceflight he Conjunction Assessment Risk Analysis (CARA) was stood up to offer this service to all NASA robotic satellites Currently provides service to 70 operational satellites NASA unmanned operational assets Other USG assets (USGS, USAF, NOAA) International partner assets Conjunction Assessment (CA) is the process of identifying close approaches between two orbiting objects; sometimes called conjunction screening The Joint Space Operations Center (JSpOC) a USAF unit at Vandenberg AFB, maintains the high accuracy catalog of space objects, screens CARA-supported assets against the catalog, performs OD tasking, and generates close approach data.

  6. The 727 approach energy management system avionics specification (preliminary)

    NASA Technical Reports Server (NTRS)

    Jackson, D. O.; Lambregts, A. A.

    1976-01-01

    Hardware and software requirements for an Approach Energy Management System (AEMS) consisting of an airborne digital computer and cockpit displays are presented. The displays provide the pilot with a visual indication of when to manually operate the gear, flaps, and throttles during a delayed flap approach so as to reduce approach time, fuel consumption, and community noise. The AEMS is an independent system that does not interact with other navigation or control systems, and is compatible with manually flown or autopilot coupled approaches. Operational use of the AEMS requires a DME ground station colocated with the flight path reference.

  7. Spacecraft Autonomy and Automation: A Comparative Analysis of Strategies for Cost Effective Mission Operations

    NASA Technical Reports Server (NTRS)

    Wright, Nathaniel, Jr.

    2000-01-01

    The evolution of satellite operations over the last 40 years has drastically changed. October 4, 1957 (during the cold war) the Soviet Union launched the world's first spacecraft into orbit. The Sputnik satellite orbited Earth for three months and catapulted the United States into a race for dominance in space. A year after Sputnik, President Dwight Eisenhower formed the National Space and Aeronautics Administration (NASA). With a team of scientists and engineers, NASA successfully launched Explorer 1, the first US satellite to orbit Earth. During these early years, massive amounts of ground support equipment and operators were required to successfully operate spacecraft vehicles. Today, budget reductions and technological advances have forced new approaches to spacecraft operations. These approaches require increasingly complex, on board spacecraft systems, that enable autonomous operations, resulting in more cost-effective mission operations. NASA's Goddard Space Flight Center, considered world class in satellite development and operations, has developed and operated over 200 satellites during its 40 years of existence. NASA Goddard is adopting several new millennium initiatives that lower operational costs through the spacecraft autonomy and automation. This paper examines NASA's approach to spacecraft autonomy and ground system automation through a comparative analysis of satellite missions for Hubble Space Telescope-HST, Near Earth Asteroid Rendezvous-NEAR, and Solar Heliospheric Observatory-SoHO, with emphasis on cost reduction methods, risk analysis and anomalies and strategies employed for mitigating risk.

  8. Disease severity, not operative approach, drives organ space infection after pediatric appendectomy.

    PubMed

    Kelly, Kristin N; Fleming, Fergal J; Aquina, Christopher T; Probst, Christian P; Noyes, Katia; Pegoli, Walter; Monson, John R T

    2014-09-01

    This study examines patient and operative factors associated with organ space infection (OSI) in children after appendectomy, specifically focusing on the role of operative approach. Although controversy exists regarding the risk of increased postoperative intra-abdominal infections after laparoscopic appendectomy, this approach has been largely adopted in the treatment of pediatric acute appendicitis. Children aged 2 to 18 years undergoing open or laparoscopic appendectomy for acute appendicitis were selected from the 2012 American College of Surgeons Pediatric National Surgical Quality Improvement Program database. Univariate analysis compared patient and operative characteristics with 30-day OSI and incisional complication rates. Factors with a P value of less than 0.1 and clinical importance were included in the multivariable logistic regression models. A P value less than 0.05 was considered significant. For 5097 children undergoing appendectomy, 4514 surgical procedures (88.6%) were performed laparoscopically. OSI occurred in 155 children (3%), with half of these infections developing postdischarge. Significant predictors for OSI included complicated appendicitis, preoperative sepsis, wound class III/IV, and longer operative time. Although 5.2% of patients undergoing open surgery developed OSI (odds ratio = 1.82; 95% confidence interval, 1.21-2.76; P = 0.004), operative approach was not associated with increased relative odds of OSI (odds ratio = 0.99; confidence interval, 0.64-1.55; P = 0.970) after adjustment for other risk factors. Overall, the model had excellent predictive ability (c-statistic = 0.837). This model suggests that disease severity, not operative approach, as previously suggested, drives OSI development in children. Although 88% of appendectomies in this population were performed laparoscopically, these findings support utilization of the surgeon's preferred surgical technique and may help guide postoperative counsel in high-risk children.

  9. Comparison of Wiltse's paraspinal approach and open book laminectomy for thoracolumbar burst fractures with greenstick lamina fractures: a randomized controlled trial.

    PubMed

    Chen, Zhi-da; Wu, Jin; Yao, Xiao-Tao; Cai, Tao-Yi; Zeng, Wen-Rong; Lin, Bin

    2018-03-02

    Posterior short-segment pedicle screw fixation is used to treat thoracolumbar burst fractures. However, no randomized controlled studies have compared the efficacy of the two approaches--the Wiltse's paraspinal approach and open book laminectomy in the treatment of thoracolumbar burst fractures with greenstick lamina fractures. Patients with burst fractures of the thoracolumbar spine without neurological deficit were randomized to receive either the Wiltse's paraspinal approach (group A, 24 patients) or open book laminectomy (group B, 23 patients). Patients were followed postoperatively for average of 27.4 months. Clinical and radiographic data of the two approaches were collected and compared. Our results showed the anterior segmental height, kyphotic angle, visual analog scale (VAS) score, and Smiley-Webster Scale (SWS) score significantly improved postoperatively in both groups, indicating that both the Wiltse's paraspinal approach and open book laminectomy can effectively treat thoracolumbar burst fractures with greenstick lamina fractures. The Wiltse's paraspinal approach was found to have significantly shorter operating time, less blood loss, and shorter length of hospital stay compared to open book laminectomy. However, there were two (2/24) patients in group A that had neurological deficits postoperatively and required a second exploratory operation. Dural tears and/or cauda equina entrapment were subsequently found in four patients in group B and all two patients of neurological deficits in group A during operation. No screw loosening, plate breakage, or other internal fixation failures were found at final follow-up. The results demonstrated that either of the two surgical approaches can achieve satisfactory results in treating thoracolumbar burst fractures in patients with greenstick lamina fractures. However, if there is any clinical or radiographic suspicion of a dural tear and/or cauda equina entrapment pre-operation, patients should receive an open book laminectomy to avoid a second exploratory operation. More research is still needed to optimize clinical decision-making regarding surgical approach.

  10. Space Station overall management approach for operations

    NASA Technical Reports Server (NTRS)

    Paules, G.

    1986-01-01

    An Operations Management Concept developed by NASA for its Space Station Program is discussed. The operational goals, themes, and design principles established during program development are summarized. The major operations functions are described, including: space systems operations, user support operations, prelaunch/postlanding operations, logistics support operations, market research, and cost/financial management. Strategic, tactical, and execution levels of operational decision-making are defined.

  11. Discrete Fourier Transform Analysis in a Complex Vector Space

    NASA Technical Reports Server (NTRS)

    Dean, Bruce H.

    2009-01-01

    Alternative computational strategies for the Discrete Fourier Transform (DFT) have been developed using analysis of geometric manifolds. This approach provides a general framework for performing DFT calculations, and suggests a more efficient implementation of the DFT for applications using iterative transform methods, particularly phase retrieval. The DFT can thus be implemented using fewer operations when compared to the usual DFT counterpart. The software decreases the run time of the DFT in certain applications such as phase retrieval that iteratively call the DFT function. The algorithm exploits a special computational approach based on analysis of the DFT as a transformation in a complex vector space. As such, this approach has the potential to realize a DFT computation that approaches N operations versus Nlog(N) operations for the equivalent Fast Fourier Transform (FFT) calculation.

  12. Design and Development of a Rapid Research, Design, and Development Platform for In-Situ Testing of Tools and Concepts for Trajectory-Based Operations

    NASA Technical Reports Server (NTRS)

    Underwood, Matthew C.

    2017-01-01

    To provide justification for equipping a fleet of aircraft with avionics capable of supporting trajectory-based operations, significant flight testing must be accomplished. However, equipping aircraft with these avionics and enabling technologies to communicate the clearances required for trajectory-based operations is cost-challenging using conventional avionics approaches. This paper describes an approach to minimize the costs and risks of flight testing these technologies in-situ, discusses the test-bed platform developed, and highlights results from a proof-of-concept flight test campaign that demonstrates the feasibility and efficiency of this approach.

  13. Lunar Surface Mission Operations Scenario and Considerations

    NASA Technical Reports Server (NTRS)

    Arnold, Larissa S.; Torney, Susan E.; Rask, John Doug; Bleisath, Scott A.

    2006-01-01

    Planetary surface operations have been studied since the last visit of humans to the Moon, including conducting analog missions. Mission Operations lessons from these activities are summarized. Characteristics of forecasted surface operations are compared to current human mission operations approaches. Considerations for future designs of mission operations are assessed.

  14. Combined abdominal and perineal approach for delayed restoration of bowel continuity after low anterior resection in females.

    PubMed

    Abou-Zeid, Ahmed A; Makki, Mahmoud T

    2007-04-01

    Restoration of bowel continuity after Hartmann's operation is the surgeon's goal and the patient's hope. This operation is technically demanding with reportedly high morbidity and mortality. A short distal rectal stump often makes the operation more difficult. In this article, we describe a combined abdominal and perineal approach, which can possibly make delayed restoration of bowel continuity after low anterior rectal resection an easier procedure.

  15. Transparent lattice characterization with gated turn-by-turn data of diagnostic bunch train

    NASA Astrophysics Data System (ADS)

    Li, Yongjun; Cheng, Weixing; Ha, Kiman; Rainer, Robert

    2017-11-01

    Methods of characterization of a storage ring's lattice have traditionally been intrusive to routine operations. More importantly, the lattice seen by particles can drift with the beam current due to collective effects. To circumvent this, we have developed a novel approach for dynamically characterizing a storage ring's lattice that is transparent to operations. Our approach adopts a dedicated filling pattern which has a short, separate diagnostic bunch train (DBT). Through the use of a bunch-by-bunch feedback system, the DBT can be selectively excited on demand. Gated functionality of a beam position monitor system is capable of collecting turn-by-turn data of the DBT, from which the lattice can then be characterized after excitation. As the DBT comprises only about one percent of the total operational bunches, the effects of its excitation are negligible to users. This approach allows us to localize the distributed quadrupolar wakefields generated in the storage ring vacuum chamber during beam accumulation. While effectively transparent to operations, our approach enables us to dynamically control the beta beat and phase beat, and unobtrusively optimize performance of the National Synchrotron Light Source-II accelerator during routine operations.

  16. Transparent lattice characterization with gated turn-by-turn data of diagnostic bunch train

    DOE PAGES

    Li, Yongjun; Cheng, Weixing; Ha, Kiman; ...

    2017-11-21

    Methods of characterization of a storage ring's lattice have traditionally been intrusive to routine operations. More importantly, the lattice seen by particles can drift with the beam current due to collective effects. To circumvent this, we have developed a novel approach for dynamically characterizing a storage ring's lattice that is transparent to operations. Our approach adopts a dedicated filling pattern which has a short, separate Diagnostic Bunch-Train (DBT). Through the use of a bunch-by-bunch feedback system, the DBT can be selectively excited on-demand. Gated functionality of a beam position monitor system is capable of collecting turn-by-turn data of the DBT,more » from which the lattice can then be characterized after excitation. As the DBT comprises only about one percent of the total operational bunches, the effects of its excitation are negligible to users. Therefore, this approach allows us to localize the distributed quadrupolar wake fields generated in the storage ring vacuum chamber during beam accumulation. While effectively transparent to operations, our approach enables us to dynamically control the beta-beat and phase-beat, and unobtrusively optimize performance of National Synchrotron Light Source-II accelerator during routine operations.« less

  17. Development, design, and flight test evaluation of a continuous descent approach procedure for nighttime operation at Louisville International Airport.

    DOT National Transportation Integrated Search

    2006-01-09

    The design and flight test of a Continuous Descent Approach (CDA) : procedure for regular nighttime operation at Louisville : International Airport are described in this report. Results of : the analyses of aircraft and FMS performance indicate that ...

  18. Two Approaches to Measuring Task Interdependence in Elementary Schools.

    ERIC Educational Resources Information Center

    Charters, W. W., Jr.

    This report compares two approaches to measuring task interdependence, a theoretically fruitful concept for analyzing an organization's technical system. Task interdependence exists among operating personnel in the degree that task performance of one operative constrains, augments, or otherwise poses contingencies for the performance of another.…

  19. Log sort yard economics, planning, and feasibility

    Treesearch

    John Rusty Dramm; Robert Govett; Ted Bilek; Gerry L. Jackson

    2004-01-01

    This publication discusses basic marketing and economic concepts, planning approach, and feasibility methodology for assessing log sort yard operations. Special attention is given to sorting small diameter and underutilized logs from forest restoration, fuels reduction, and thinning operations. A planned programming approach of objectively determining the feasibility...

  20. Direct cost comparison of minimally invasive punch technique versus traditional approaches for percutaneous bone anchored hearing devices.

    PubMed

    Sardiwalla, Yaeesh; Jufas, Nicholas; Morris, David P

    2017-06-12

    Minimally Invasive Ponto Surgery (MIPS) was recently described as a new technique to facilitate the placement of percutaneous bone anchored hearing devices. The procedure has resulted in a simplification of the surgical steps and a dramatic reduction in surgical time while maintaining excellent patient outcomes. Given these developments, our group sought to move the procedure from the main operating suite where they have traditionally been performed. This study aims to test the null hypothesis that MIPS and open approaches have the same direct costs for the implantation of percutaneous bone anchored hearing devices in a Canadian public hospital setting. A retrospective direct cost comparison of MIPS and open approaches for the implantation of bone conduction implants was conducted. Indirect and future costs were not included in the fiscal analysis. A simple cost comparison of the two approaches was made considering time, staff and equipment needs. All 12 operations were performed on adult patients from 2013 to 2016 by the same surgeon at a single hospital site. MIPS has a total mean reduction in cost of CAD$456.83 per operation from the hospital perspective when compared to open approaches. The average duration of the MIPS operation was 7 min, which is on average 61 min shorter compared with open approaches. The MIPS technique was more cost effective than traditional open approaches. This primarily reflects a direct consequence of a reduction in surgical time, with further contributions from reduced staffing and equipment costs. This simple, quick intervention proved to be feasible when performed outside the main operating room. A blister pack of required equipment could prove convenient and further reduce costs.

  1. An alternative approach for neural network evolution with a genetic algorithm: crossover by combinatorial optimization.

    PubMed

    García-Pedrajas, Nicolás; Ortiz-Boyer, Domingo; Hervás-Martínez, César

    2006-05-01

    In this work we present a new approach to crossover operator in the genetic evolution of neural networks. The most widely used evolutionary computation paradigm for neural network evolution is evolutionary programming. This paradigm is usually preferred due to the problems caused by the application of crossover to neural network evolution. However, crossover is the most innovative operator within the field of evolutionary computation. One of the most notorious problems with the application of crossover to neural networks is known as the permutation problem. This problem occurs due to the fact that the same network can be represented in a genetic coding by many different codifications. Our approach modifies the standard crossover operator taking into account the special features of the individuals to be mated. We present a new model for mating individuals that considers the structure of the hidden layer and redefines the crossover operator. As each hidden node represents a non-linear projection of the input variables, we approach the crossover as a problem on combinatorial optimization. We can formulate the problem as the extraction of a subset of near-optimal projections to create the hidden layer of the new network. This new approach is compared to a classical crossover in 25 real-world problems with an excellent performance. Moreover, the networks obtained are much smaller than those obtained with classical crossover operator.

  2. Enhanced Flight Vision Systems Operational Feasibility Study Using Radar and Infrared Sensors

    NASA Technical Reports Server (NTRS)

    Etherington, Timothy J.; Kramer, Lynda J.; Severance, Kurt; Bailey, Randall E.; Williams, Steven P.; Harrison, Stephanie J.

    2015-01-01

    Approach and landing operations during periods of reduced visibility have plagued aircraft pilots since the beginning of aviation. Although techniques are currently available to mitigate some of the visibility conditions, these operations are still ultimately limited by the pilot's ability to "see" required visual landing references (e.g., markings and/or lights of threshold and touchdown zone) and require significant and costly ground infrastructure. Certified Enhanced Flight Vision Systems (EFVS) have shown promise to lift the obscuration veil. They allow the pilot to operate with enhanced vision, in lieu of natural vision, in the visual segment to enable equivalent visual operations (EVO). An aviation standards document was developed with industry and government consensus for using an EFVS for approach, landing, and rollout to a safe taxi speed in visibilities as low as 300 feet runway visual range (RVR). These new standards establish performance, integrity, availability, and safety requirements to operate in this regime without reliance on a pilot's or flight crew's natural vision by use of a fail-operational EFVS. A pilot-in-the-loop high-fidelity motion simulation study was conducted at NASA Langley Research Center to evaluate the operational feasibility, pilot workload, and pilot acceptability of conducting straight-in instrument approaches with published vertical guidance to landing, touchdown, and rollout to a safe taxi speed in visibility as low as 300 feet RVR by use of vision system technologies on a head-up display (HUD) without need or reliance on natural vision. Twelve crews flew various landing and departure scenarios in 1800, 1000, 700, and 300 RVR. This paper details the non-normal results of the study including objective and subjective measures of performance and acceptability. The study validated the operational feasibility of approach and departure operations and success was independent of visibility conditions. Failures were handled within the lateral confines of the runway for all conditions tested. The fail-operational concept with pilot in the loop needs further study.

  3. Crew-Centered Operations: What HAL 9000 Should Have Been

    NASA Technical Reports Server (NTRS)

    Korsmeyer, David J.; Clancy, Daniel J.; Crawford, James M.; Drummond, Mark E.

    2005-01-01

    To date, manned space flight has maintained the locus of control for the mission on the ground. Mission control performs tasks such as activity planning, system health management, resource allocation, and astronaut health monitoring. Future exploration missions require the locus of control to shift to on-board due light speed constraints and potential loss of communication. The lunar campaign must begin to utilize a shared control approach to validate and understand the limitations of the technology allowing astronauts to oversee and direct aspects of operation that require timely decision making. Crew-centered Operations require a system-level approach that integrates multiple technologies together to allow a crew-prime concept of operations. This paper will provide an overview of the driving mission requirements, highlighting the limitations of existing approaches to mission operations and identifying the critical technologies necessary to enable a crew-centered mode of operations. The paper will focus on the requirements, trade spaces, and concepts for fulfillment of this capability. The paper will provide a broad overview of relevant technologies including: Activity Planning and Scheduling; System Monitoring; Repair and Recovery; Crew Work Practices.

  4. Combining task-evoked and spontaneous activity to improve pre-operative brain mapping with fMRI

    PubMed Central

    Fox, Michael D.; Qian, Tianyi; Madsen, Joseph R.; Wang, Danhong; Li, Meiling; Ge, Manling; Zuo, Huan-cong; Groppe, David M.; Mehta, Ashesh D.; Hong, Bo; Liu, Hesheng

    2016-01-01

    Noninvasive localization of brain function is used to understand and treat neurological disease, exemplified by pre-operative fMRI mapping prior to neurosurgical intervention. The principal approach for generating these maps relies on brain responses evoked by a task and, despite known limitations, has dominated clinical practice for over 20 years. Recently, pre-operative fMRI mapping based on correlations in spontaneous brain activity has been demonstrated, however this approach has its own limitations and has not seen widespread clinical use. Here we show that spontaneous and task-based mapping can be performed together using the same pre-operative fMRI data, provide complimentary information relevant for functional localization, and can be combined to improve identification of eloquent motor cortex. Accuracy, sensitivity, and specificity of our approach are quantified through comparison with electrical cortical stimulation mapping in eight patients with intractable epilepsy. Broad applicability and reproducibility of our approach is demonstrated through prospective replication in an independent dataset of six patients from a different center. In both cohorts and every individual patient, we see a significant improvement in signal to noise and mapping accuracy independent of threshold, quantified using receiver operating characteristic curves. Collectively, our results suggest that modifying the processing of fMRI data to incorporate both task-based and spontaneous activity significantly improves functional localization in pre-operative patients. Because this method requires no additional scan time or modification to conventional pre-operative data acquisition protocols it could have widespread utility. PMID:26408860

  5. Corneal approach 20 Guage vitrectomy system for the management of congenital cataract

    PubMed Central

    Memon, Mariya Nazish; Bukhari, Sadia; Bhutto, Israr Ahmed

    2016-01-01

    Objective: To evaluate the efficacy and complications of 20 gauge vitrectomy via corneal approach for the management of congenital cataract. Method: We performed anterior capsular vitreorhexis, lens matter aspiration (LMA), primary posterior vitrectorhexis and anterior vitrectomy via corneal approach using 20 gauge vitrectomy system in children younger than two years of age with congenital cataract between January 2014 to December 2014. The intra and postoperative complications were observed. Results: Twenty nine eyes of 21 children were included in this study. Congenital cataract surgery using 20 gauge vitrectomy system via corneal approach did not reveal any intra operative complication. Post operatively all children were able to freely open their operated eyes. Conjunctival congestion at the incision site in four eyes and mild anterior chamber reaction in 8 eyes were seen on 1st daywhich resolved at one week follow up. Other major post operative complications such as inflammatory membrane, irregular pupil, posterior/anterior syneache and opacification of visual axis were not seen during follow up period. Conclusion: The 20-gauge vitrectomy system via corneal approach is easy to perform, is less time consuming, safe and effective for the management of congenital cataract in younger children. PMID:27182257

  6. Corneal approach 20 Guage vitrectomy system for the management of congenital cataract.

    PubMed

    Memon, Mariya Nazish; Bukhari, Sadia; Bhutto, Israr Ahmed

    2016-01-01

    To evaluate the efficacy and complications of 20 gauge vitrectomy via corneal approach for the management of congenital cataract. We performed anterior capsular vitreorhexis, lens matter aspiration (LMA), primary posterior vitrectorhexis and anterior vitrectomy via corneal approach using 20 gauge vitrectomy system in children younger than two years of age with congenital cataract between January 2014 to December 2014. The intra and postoperative complications were observed. Twenty nine eyes of 21 children were included in this study. Congenital cataract surgery using 20 gauge vitrectomy system via corneal approach did not reveal any intra operative complication. Post operatively all children were able to freely open their operated eyes. Conjunctival congestion at the incision site in four eyes and mild anterior chamber reaction in 8 eyes were seen on 1(st) daywhich resolved at one week follow up. Other major post operative complications such as inflammatory membrane, irregular pupil, posterior/anterior syneache and opacification of visual axis were not seen during follow up period. The 20-gauge vitrectomy system via corneal approach is easy to perform, is less time consuming, safe and effective for the management of congenital cataract in younger children.

  7. Nonnormal operators in physics, a singular-vectors approach: illustration in polarization optics.

    PubMed

    Tudor, Tiberiu

    2016-04-20

    The singular-vectors analysis of a general nonnormal operator defined on a finite-dimensional complex vector space is given in the frame of a pure operatorial ("nonmatrix," "coordinate-free") approach, performed in a Dirac language. The general results are applied in the field of polarization optics, where the nonnormal operators are widespread as operators of various polarization devices. Two nonnormal polarization devices representative for the class of nonnormal and even pathological operators-the standard two-layer elliptical ideal polarizer (singular operator) and the three-layer ambidextrous ideal polarizer (singular and defective operator)-are analyzed in detail. It is pointed out that the unitary polar component of the operator exists and preserves, in such pathological case too, its role of converting the input singular basis of the operator in its output singular basis. It is shown that for any nonnormal ideal polarizer a complementary one exists, so that the tandem of their operators uniquely determines their (common) unitary polar component.

  8. The operational context of care sport connectors in the Netherlands.

    PubMed

    Leenaars, K E F; van der Velden-Bollemaat, E C; Smit, E; Wagemakers, A; Molleman, G R M; Koelen, M A

    2017-02-22

    To stimulate physical activity (PA) and guide primary care patients towards local sport facilities, Care Sport Connectors (CSCs), to whom a broker role has been ascribed, were introduced in 2012 in the Netherlands. The aim of this study is to describe CSCs' operational context. A theoretical framework was developed and used as the starting point for this study. Group interviews were held with policymakers in nine participating municipalities, and, when applicable, the CSC's manager was also present. Prior to the interviews, a first outline of the operational context was mapped, based on the analysis of policy documents and a questionnaire completed by the policymakers. A deductive content analysis, based on the theoretical framework, was used to analyse the interviews. Differences were found in CSCs' operational context in the different municipalities, especially the extent to which municipalities adopted an integral approach. An integral approach consists of an integral policy in combination with an imbedding of this policy in partnerships at management level. This integral approach is reflected in the activities of other municipal operations, for example the implementation of health and PA programs by different organisations. Given the CSC mandate, we think that this integral approach may be supportive of the CSCs' work, because it is reflected in other operations of the municipalities and thus creates conditions for the CSCs' work. Further study is required to ascertain whether this integral approach is actually supporting CSCs in their work to connect the primary care and the PA sector. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Costs and benefits of different methods of esophagectomy for esophageal cancer.

    PubMed

    Yanasoot, Alongkorn; Yolsuriyanwong, Kamtorn; Ruangsin, Sakchai; Laohawiriyakamol, Supparerk; Sunpaweravong, Somkiat

    2017-01-01

    Background A minimally invasive approach to esophagectomy is being used increasingly, but concerns remain regarding the feasibility, safety, cost, and outcomes. We performed an analysis of the costs and benefits of minimally invasive, hybrid, and open esophagectomy approaches for esophageal cancer surgery. Methods The data of 83 consecutive patients who underwent a McKeown's esophagectomy at Prince of Songkla University Hospital between January 2008 and December 2014 were analyzed. Open esophagectomy was performed in 54 patients, minimally invasive esophagectomy in 13, and hybrid esophagectomy in 16. There were no differences in patient characteristics among the 3 groups Minimally invasive esophagectomy was undertaken via a thoracoscopic-laparoscopic approach, hybrid esophagectomy via a thoracoscopic-laparotomy approach, and open esophagectomy by a thoracotomy-laparotomy approach. Results Minimally invasive esophagectomy required a longer operative time than hybrid or open esophagectomy ( p = 0.02), but these patients reported less postoperative pain ( p = 0.01). There were no significant differences in blood loss, intensive care unit stay, hospital stay, or postoperative complications among the 3 groups. Minimally invasive esophagectomy incurred higher operative and surgical material costs than hybrid or open esophagectomy ( p = 0.01), but there were no significant differences in inpatient care and total hospital costs. Conclusion Minimally invasive esophagectomy resulted in the least postoperative pain but the greatest operative cost and longest operative time. Open esophagectomy was associated with the lowest operative cost and shortest operative time but the most postoperative pain. Hybrid esophagectomy had a shorter learning curve while sharing the advantages of minimally invasive esophagectomy.

  10. Energy and operation management of a microgrid using particle swarm optimization

    NASA Astrophysics Data System (ADS)

    Radosavljević, Jordan; Jevtić, Miroljub; Klimenta, Dardan

    2016-05-01

    This article presents an efficient algorithm based on particle swarm optimization (PSO) for energy and operation management (EOM) of a microgrid including different distributed generation units and energy storage devices. The proposed approach employs PSO to minimize the total energy and operating cost of the microgrid via optimal adjustment of the control variables of the EOM, while satisfying various operating constraints. Owing to the stochastic nature of energy produced from renewable sources, i.e. wind turbines and photovoltaic systems, as well as load uncertainties and market prices, a probabilistic approach in the EOM is introduced. The proposed method is examined and tested on a typical grid-connected microgrid including fuel cell, gas-fired microturbine, wind turbine, photovoltaic and energy storage devices. The obtained results prove the efficiency of the proposed approach to solve the EOM of the microgrids.

  11. 14 CFR 136.13 - Helicopter performance plan and operations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... for the approach to and transition from a hover for the purpose of takeoff and landing, or during... the caution/warning/avoid area of the limiting height/velocity diagram. (c) Except for the approach to... into consideration the maximum density altitude for which the operation is planned, in order to...

  12. 14 CFR 136.13 - Helicopter performance plan and operations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... for the approach to and transition from a hover for the purpose of takeoff and landing, or during... the caution/warning/avoid area of the limiting height/velocity diagram. (c) Except for the approach to... into consideration the maximum density altitude for which the operation is planned, in order to...

  13. 78 FR 67297 - Establishment of Class E Airspace; Curtis, NE

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-12

    ... approach procedures. Controlled airspace is needed for the safety and management of IFR operations at the... Instrument Approach Procedures at Curtis Municipal Airport. The FAA is taking this action to enhance the safety and management of Instrument Flight Rule (IFR) operations at the airport. DATES: Effective date...

  14. Training: An Opportunity for People with Disabilities in School Foodservice Operations

    ERIC Educational Resources Information Center

    Paez, Paola; Arendt, Susan; Strohbehn, Catherine

    2011-01-01

    Purpose/Objectives: This study assessed current training methods and topics used at public school foodservice operations as well as school foodservice representatives' attitudes toward training employees with disabilities. Methods: A mixed method approach of data collection included two phases. Phase I used a more qualitative approach; interviews…

  15. Safety and operational analysis of lane widths in mid-block segments and intersection approaches in the urban environment in Nebraska.

    DOT National Transportation Integrated Search

    2015-04-01

    This research examined the safety and operational effects of roadway lane width on mid-block segments between : signalized intersections as well as on signalized intersection approaches in the urban environments of Lincoln and Omaha, : Nebraska. In t...

  16. Noise measurements taken at LAX during operational evaluation of two-segment approaches in a 727-200 aircraft

    NASA Technical Reports Server (NTRS)

    Tanner, C. S.; Glass, R. E.

    1973-01-01

    A series of seven noise measurements were made each day over a period of fifteen days. The first and last flights each day were made by a specially instrumented 727-200 aircraft being used to evaluate the operational effectiveness of two-segment noise abatement approaches in scheduled service. Noise measurements were made to determine the noise reduction benefits of the two-segment approaches.

  17. Assessment of Manual Operation Time for the Manufacturing of Thin Film Transistor Liquid Crystal Display: A Bayesian Approach

    NASA Astrophysics Data System (ADS)

    Shen, Chien-wen

    2009-01-01

    During the processes of TFT-LCD manufacturing, steps like visual inspection of panel surface defects still heavily rely on manual operations. As the manual inspection time of TFT-LCD manufacturing could range from 4 hours to 1 day, the reliability of time forecasting is thus important for production planning, scheduling and customer response. This study would like to propose a practical and easy-to-implement prediction model through the approach of Bayesian networks for time estimation of manual operated procedures in TFT-LCD manufacturing. Given the lack of prior knowledge about manual operation time, algorithms of necessary path condition and expectation-maximization are used for structural learning and estimation of conditional probability distributions respectively. This study also applied Bayesian inference to evaluate the relationships between explanatory variables and manual operation time. With the empirical applications of this proposed forecasting model, approach of Bayesian networks demonstrates its practicability and prediction accountability.

  18. 3D printed renal cancer models derived from MRI data: application in pre-surgical planning.

    PubMed

    Wake, Nicole; Rude, Temitope; Kang, Stella K; Stifelman, Michael D; Borin, James F; Sodickson, Daniel K; Huang, William C; Chandarana, Hersh

    2017-05-01

    To determine whether patient-specific 3D printed renal tumor models change pre-operative planning decisions made by urological surgeons in preparation for complex renal mass surgical procedures. From our ongoing IRB approved study on renal neoplasms, ten renal mass cases were retrospectively selected based on Nephrometry Score greater than 5 (range 6-10). A 3D post-contrast fat-suppressed gradient-echo T1-weighted sequence was used to generate 3D printed models. The cases were evaluated by three experienced urologic oncology surgeons in a randomized fashion using (1) imaging data on PACS alone and (2) 3D printed model in addition to the imaging data. A questionnaire regarding surgical approach and planning was administered. The presumed pre-operative approaches with and without the model were compared. Any change between the presumed approaches and the actual surgical intervention was recorded. There was a change in planned approach with the 3D printed model for all ten cases with the largest impact seen regarding decisions on transperitoneal or retroperitoneal approach and clamping, with changes seen in 30%-50% of cases. Mean parenchymal volume loss for the operated kidney was 21.4%. Volume losses >20% were associated with increased ischemia times and surgeons tended to report a different approach with the use of the 3D model compared to that with imaging alone in these cases. The 3D printed models helped increase confidence regarding the chosen operative procedure in all cases. Pre-operative physical 3D models created from MRI data may influence surgical planning for complex kidney cancer.

  19. Reliability and quality assurance on the MOD 2 wind system

    NASA Technical Reports Server (NTRS)

    Mason, W. E. B.; Jones, B. G.

    1981-01-01

    The Safety, Reliability, and Quality Assurance (R&QA) approach developed for the largest wind turbine generator, the Mod 2, is described. The R&QA approach assures that the machine is not hazardous to the public or to the operating personnel, is operated unattended on a utility grid, demonstrates reliable operation, and helps establish the quality assurance and maintainability requirements for future wind turbine projects. The significant guideline consisted of a failure modes and effects analysis (FMEA) during the design phase, hardware inspections during parts fabrication, and three simple documents to control activities during machine construction and operation.

  20. Hierarchical analytical and simulation modelling of human-machine systems with interference

    NASA Astrophysics Data System (ADS)

    Braginsky, M. Ya; Tarakanov, D. V.; Tsapko, S. G.; Tsapko, I. V.; Baglaeva, E. A.

    2017-01-01

    The article considers the principles of building the analytical and simulation model of the human operator and the industrial control system hardware and software. E-networks as the extension of Petri nets are used as the mathematical apparatus. This approach allows simulating complex parallel distributed processes in human-machine systems. The structural and hierarchical approach is used as the building method for the mathematical model of the human operator. The upper level of the human operator is represented by the logical dynamic model of decision making based on E-networks. The lower level reflects psychophysiological characteristics of the human-operator.

  1. CLEAR: Communications Link Expert Assistance Resource

    NASA Technical Reports Server (NTRS)

    Hull, Larry G.; Hughes, Peter M.

    1987-01-01

    Communications Link Expert Assistance Resource (CLEAR) is a real time, fault diagnosis expert system for the Cosmic Background Explorer (COBE) Mission Operations Room (MOR). The CLEAR expert system is an operational prototype which assists the MOR operator/analyst by isolating and diagnosing faults in the spacecraft communication link with the Tracking and Data Relay Satellite (TDRS) during periods of realtime data acquisition. The mission domain, user requirements, hardware configuration, expert system concept, tool selection, development approach, and system design were discussed. Development approach and system implementation are emphasized. Also discussed are system architecture, tool selection, operation, and future plans.

  2. A correlational approach to predicting operator status

    NASA Technical Reports Server (NTRS)

    Shingledecker, Clark A.

    1988-01-01

    This paper discusses a research approach for identifying and validating candidate physiological and behavioral parameters which can be used to predict the performance capabilities of aircrew and other system operators. In this methodology, concurrent and advance correlations are computed between predictor values and criterion performance measures. Continuous performance and sleep loss are used as stressors to promote performance variation. Preliminary data are presented which suggest dependence of prediction capability on the resource allocation policy of the operator.

  3. The Design and Implementation of an Operating System for the IBM Personal Computer.

    DTIC Science & Technology

    1984-12-01

    comprehensive study of an actual operating system in an effort to show students how theory has been put into action (Lions, 1978; McCharen, 1980). Another...Freedman, 1977). However, since it is easier to develop and maintain a program written in a high-order language (HOL), Pascal was chosen to be the primary...monolithic monitor approach and the kernel approach are strategies which can be used to structure operating systems ( Deitel , 1983; Holt, 1983

  4. Heisenberg operator approach for spin squeezing dynamics

    NASA Astrophysics Data System (ADS)

    Bhattacherjee, Aranya Bhuti; Sharma, Deepti; Pelster, Axel

    2017-12-01

    We reconsider the one-axis twisting Hamiltonian, which is commonly used for generating spin squeezing, and treat its dynamics within the Heisenberg operator approach. To this end we solve the underlying Heisenberg equations of motion perturbatively and evaluate the expectation values of the resulting time-dependent Heisenberg operators in order to determine approximately the dynamics of spin squeezing. Comparing our results with those originating from exact numerics reveals that they are more accurate than the commonly used frozen spin approximation.

  5. Modelling & Simulation Support to the Effects Based Approach to Operations - Observations from Using GAMMA in MNE 4

    DTIC Science & Technology

    2006-09-01

    The aim of the two parts of the experiment was identical: To explore concepts and supporting tools for Effects Based Approach to Operations (EBAO...feedback on the PMESII factors over time and the degree of achievement of the Operational Endstate. Modelling & Simulation Support to the Effects ...specific situation depends also on his interests. GAMMA provides two different methods: 1. The importance for different PMESII factors (ie potential

  6. Analysis and Long-Term Follow-Up of the Surgical Treatment of Children With Craniopharyngioma.

    PubMed

    Cheng, Jing; Shao, Qiang; Pan, Zhiyong; You, Jin

    2016-11-01

    To investigate the relationship between the operative approach, clinical pathological factors, and curative effect of the surgical treatment in the patients with craniopharyngioma; to provide a theoretical basis for determining the prognosis and reducing the recurrence rate during the long-term postoperative follow-up in children. This was a retrospective analysis of the clinical data of 92 children who underwent surgical treatment in our department from May 2011 to January 2005. Long-term follow-up was performed from 12 months to 8 years. The pterional approach was used in 49 patients, the interhemispheric approach in 20 patients, the corpus callosum approach in 16 patients, and the butterfly approach in 7 patients. Pathological classification was performed by hematoxylin and eosin stain staining of the pathological tissues and evaluated according to the different surgical approaches, MRI calcification status, calcification type, pathological type, whether radiotherapy was performed, postoperative recurrence, and death. For the pterion approach resection, there was near total resection in 46 patients (93.9%) with the lowest recurrence rate. The operative approach and postoperative recurrence rates were compared; the difference was statistically significant (P <0.05). For comparison of the operative approach and postoperative mortality, the difference was not statistically significant (P >0.05). There was not a significant difference between the MRI classification and postoperative recurrence rate (P >0.05). Comparing the degree of tumor calcification with the recurrence rate after operation and the mortality rate, the difference was statistically significant (P <0.05). The recurrence rate and mortality rate of adamantimous craniopharyngioma and squamous papillary craniopharyngioma in 2 groups following operation were compared, and the differences were statistically significant (P <0.05). Postoperative adjuvant radiotherapy was compared with the postoperative recurrence rate and mortality; the differences were statistically significant (P <0.05). The main effects on tumor recurrence include the choice of surgical approach and degree of calcification. The adamantimous craniopharyngioma relapse rate is higher, which could be because invasion of craniopharyngioma only occurs with adamantimous craniopharyngioma. Postoperative radiotherapy can significantly prolong the recurrence time and reduce the mortality rate of patients with craniopharyngioma.

  7. Computer Learning Through Piaget's Eyes.

    ERIC Educational Resources Information Center

    Huber, Leonard N.

    1985-01-01

    Discusses Piaget's pre-operational, concrete operational, and formal operational stages and shows how this information sheds light on how children approach computers and computing, particularly with the LOGO programming language. (JN)

  8. Cognitive Systems Modeling and Analysis of Command and Control Systems

    NASA Technical Reports Server (NTRS)

    Norlander, Arne

    2012-01-01

    Military operations, counter-terrorism operations and emergency response often oblige operators and commanders to operate within distributed organizations and systems for safe and effective mission accomplishment. Tactical commanders and operators frequently encounter violent threats and critical demands on cognitive capacity and reaction time. In the future they will make decisions in situations where operational and system characteristics are highly dynamic and non-linear, i.e. minor events, decisions or actions may have serious and irreversible consequences for the entire mission. Commanders and other decision makers must manage true real time properties at all levels; individual operators, stand-alone technical systems, higher-order integrated human-machine systems and joint operations forces alike. Coping with these conditions in performance assessment, system development and operational testing is a challenge for both practitioners and researchers. This paper reports on research from which the results led to a breakthrough: An integrated approach to information-centered systems analysis to support future command and control systems research development. This approach integrates several areas of research into a coherent framework, Action Control Theory (ACT). It comprises measurement techniques and methodological advances that facilitate a more accurate and deeper understanding of the operational environment, its agents, actors and effectors, generating new and updated models. This in turn generates theoretical advances. Some good examples of successful approaches are found in the research areas of cognitive systems engineering, systems theory, and psychophysiology, and in the fields of dynamic, distributed decision making and naturalistic decision making.

  9. Dynamic Computation of Change Operations in Version Management of Business Process Models

    NASA Astrophysics Data System (ADS)

    Küster, Jochen Malte; Gerth, Christian; Engels, Gregor

    Version management of business process models requires that changes can be resolved by applying change operations. In order to give a user maximal freedom concerning the application order of change operations, position parameters of change operations must be computed dynamically during change resolution. In such an approach, change operations with computed position parameters must be applicable on the model and dependencies and conflicts of change operations must be taken into account because otherwise invalid models can be constructed. In this paper, we study the concept of partially specified change operations where parameters are computed dynamically. We provide a formalization for partially specified change operations using graph transformation and provide a concept for their applicability. Based on this, we study potential dependencies and conflicts of change operations and show how these can be taken into account within change resolution. Using our approach, a user can resolve changes of business process models without being unnecessarily restricted to a certain order.

  10. Orbitopterional Craniotomy Resection of Pediatric Suprasellar Craniopharyngioma.

    PubMed

    LeFever, Devon; Storey, Chris; Guthikonda, Bharat

    2018-04-01

    The orbitopterional approach provides an excellent combination of basal access and suprasellar access. This approach also allows for less brain retraction when resecting larger suprasellar tumors that are more superiorly projecting due to a more frontal and inferior trajectory. In this operative video, the authors thoroughly detail an orbitopterional craniotomy utilizing a one-piece modified orbitozygomatic technique. This technique involves opening the craniotomy through a standard pterional incision. The craniotomy is performed using the standard three burr holes of a pterional approach; however, the osteotomy is extended anteriorly through the frontal process of the zygomatic bone as well as through the supraorbital rim. In this operative video atlas, the authors illustrate the operative anatomy, as well as surgical strategy and techniques to resect a large suprasellar craniopharyngioma in a 4-year-old male. Other reasonable approach options for a lesion of this size would include a standard pterional approach, a supraorbital approach, or expanded endoscopic transsphenoidal approach. The lesion was quite high and thus, the supraorbital approach may confine access to the superior portion of the tumor. While recognizing that some groups may have chosen the endoscopic expanded transsphenoidal approach for this lesion, the authors describe more confidence in achieving the goal of a safe and maximal resection with the orbitopterional approach. The link to the video can be found at: https://youtu.be/eznsK16BzR8 .

  11. Cyber as a Team Sport: Operationalizing a Whole-Of-Government Approach to Cyberspace Operations

    DTIC Science & Technology

    2011-06-07

    July 2010-7 June 2011 4. TITLE AND SUBTITLE • -~ ·- ~ I 5a. CONTRACT NUMBER CYBER AS A "TEAM SPORT ": OPERATIONALIZING A WHOLE-OF-GOVERNMENT APPROACH...JOINT FORCES STAFF COLLEGE JOINT ADVANCED WARFIGHTING SCHOOL CYBER AS A “TEAM SPORT ”: OPERATIONALIZING A WHOLE-OF- GOVERNMENT APPROACH...TO CYBERSPACE OPERATIONS by Elizabeth A. Myers Department of Defense CYBER AS A "TEAM SPORT ": OPERATIONALIZING A WHOLE-OF· GOVERNMENT

  12. Managing Science Operations during Planetary Surface Operations at Long Light Delay-Time Targets: The 2011 Desert RATS Test

    NASA Technical Reports Server (NTRS)

    Eppler, D. B.

    2012-01-01

    Desert Research and Technology Studies (Desert RATS) is a multi-year series of hardware and operations tests carried out annually in the high desert of Arizona in the San Francisco Volcanic Field. Conducted since 1997, these activities are designed to exercise planetary surface hardware and operations in conditions where multi-day tests are achievable. Desert RATS 2011 Science Operations Test simulated the management of crewed science operations at targets that were beyond the light delay time experienced during Low-Earth Orbit (LEO) and lunar surface missions, such as a mission to a Near-Earth Object (NEO) or the martian surface. Operations at targets at these distances are likely to be the norm as humans move out of the Earth-Moon system. Operating at these distances places significant challenges on mission operations, as the imposed light-delay time makes normal, two-way conversations extremely inefficient. Consequently, the operations approach for space missions that has been exercised during the first half-century of human space operations is no longer viable, and new approaches must be devised.

  13. Uniportal subxiphoid video-assisted thoracoscopic approach for thymectomy: a case series.

    PubMed

    Weaver, Helen; Ali, Jason M; Jiang, Lei; Yang, Chenlu; Wu, Liang; Jiang, Gening; Aresu, Giuseppe

    2017-01-01

    Minimally invasive techniques are becoming increasingly popular in thoracic surgery. Although median sternotomy is the traditional approach for thymectomy, video-assisted thoracoscopic surgery (VATS) approaches now predominate. This study reports a case series of the novel uniportal subxiphoid-VATS approach to extended thymectomy. Over the period of study (October 2014-January 2017) 17 patients underwent uniportal subxiphoid-VATS extended thymectomy for a thymic nodule at the Shanghai Pulmonary Centre. Ten patients were female, and the mean age of the cohort was 55 years. The mean size of nodule was 23.6 mm. The mean operative duration was 2.5 hours, with one conversion to thoracotomy for bleeding. The mean operative blood loss was 115 mL. The median length of hospital stay was 4 days. There were no episodes of phrenic nerve palsies. The 30-day survival was 100%. Uniportal subxiphoid-VATS is a feasible and safe surgical approach to extended thymectomy in selected patients, with good post-operative outcomes.

  14. Real-time monitoring of a microbial electrolysis cell using an electrical equivalent circuit model.

    PubMed

    Hussain, S A; Perrier, M; Tartakovsky, B

    2018-04-01

    Efforts in developing microbial electrolysis cells (MECs) resulted in several novel approaches for wastewater treatment and bioelectrosynthesis. Practical implementation of these approaches necessitates the development of an adequate system for real-time (on-line) monitoring and diagnostics of MEC performance. This study describes a simple MEC equivalent electrical circuit (EEC) model and a parameter estimation procedure, which enable such real-time monitoring. The proposed approach involves MEC voltage and current measurements during its operation with periodic power supply connection/disconnection (on/off operation) followed by parameter estimation using either numerical or analytical solution of the model. The proposed monitoring approach is demonstrated using a membraneless MEC with flow-through porous electrodes. Laboratory tests showed that changes in the influent carbon source concentration and composition significantly affect MEC total internal resistance and capacitance estimated by the model. Fast response of these EEC model parameters to changes in operating conditions enables the development of a model-based approach for real-time monitoring and fault detection.

  15. 14 CFR 91.189 - Category II and III operations: General operating rules.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... references for the intended runway is distinctly visible and identifiable to the pilot: (i) The approach... execute an appropriate missed approach whenever, prior to touchdown, the requirements of paragraph (d) of... familiarity with, the aircraft and the procedures to be used; and (3) The instrument panel in front of the...

  16. 14 CFR 91.189 - Category II and III operations: General operating rules.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... references for the intended runway is distinctly visible and identifiable to the pilot: (i) The approach... execute an appropriate missed approach whenever, prior to touchdown, the requirements of paragraph (d) of... familiarity with, the aircraft and the procedures to be used; and (3) The instrument panel in front of the...

  17. Automatic Generation of Customized, Model Based Information Systems for Operations Management.

    DTIC Science & Technology

    The paper discusses the need for developing a customized, model based system to support management decision making in the field of operations ... management . It provides a critique of the current approaches available, formulates a framework to classify logistics decisions, and suggests an approach for the automatic development of logistics systems. (Author)

  18. Retroperitoneoscopic adrenalectomy in pheochromocytoma

    PubMed Central

    Hisano, Marcelo; Vicentini, Fabio Carvalho; Srougi, Miguel

    2012-01-01

    Since the first laparoscopic adrenalectomy, the technique has evolved and it has become the standard of care for many adrenal diseases, including pheochromocytoma. Two laparoscopic accesses to the adrenal have been developed: transperitoneal and retroperitoneal. Retroperitoneoscopic adrenalectomy may be recommended for the treatment of pheochromocytoma with the same peri-operative outcomes of the transperitoneal approach because it allows direct access to the adrenal glands without increasing the operative risks. Although technically more demanding than the transperitoneal approach, retroperitoneoscopy can shorten the mean operative time, which is critical for cases with pheochromocytoma where minimizing the potential for intra-operative hemodynamic changes is essential. Blood loss and the convalescence time can be also shortened by this approach. There is no absolute indication for either the transperitoneal or retroperitoneal approach; however, the latter procedure may be the best option for patients who have undergone previous abdominal surgery and obese patients. Also, retroperitoneoscopic adrenalectomy is a good alternative for treating cases with inherited pheochromocytomas, such as multiple endocrine neoplasia type 2A, in which the pheochromocytoma is highly prevalent and frequently occurs bilaterally. PMID:22584723

  19. A Flight Examination of Operating Problems of V/STOL Aircraft in STOL-Type Landing and Approach

    NASA Technical Reports Server (NTRS)

    Innis, Robert C.; Quigley, Hervey C.

    1961-01-01

    A flight investigation has been conducted using a large twin-engine cargo aircraft to isolate the problems associated with operating propeller-driven aircraft in the STOL speed range where appreciable engine power is used to augment aerodynamic lift. The problems considered would also be representative of those of a large overloaded VTOL aircraft operating in an STOL manner with comparable thrust-to-weight ratios. The study showed that operation at low approach speeds was compromised by the necessity of maintaining high thrust to generate high lift and yet achieving the low lift-drag ratios needed for steep descents. The useable range of airspeed and flight path angle was limited by the pilot's demand for a positive climb margin at the approach speed, a suitable stall margin, and a control and/or performance margin for one engine inoperative. The optimum approach angle over an obstacle was found to be a compromise between obtaining the shortest air distance and the lowest touchdown velocity. In order to realize the greatest low-speed potential from STOL designs, the stability and control characteristics must be satisfactory.

  20. A comparison of operational and LANDSAT-aided snow water content estimation systems. [Feather River Basin, California

    NASA Technical Reports Server (NTRS)

    Sharp, J. M.; Thomas, R. W.

    1975-01-01

    How LANDSAT imagery can be cost effectively employed to augment an operational hydrologic model is described. Attention is directed toward the estimation of snow water content, a major predictor variable in the volumetric runoff forecasting model. A stratified double sampling scheme is supplemented with qualitative and quantitative analyses of existing operations to develop a comparison between the existing and satellite-aided approaches to snow water content estimation. Results show a decided advantage for the LANDSAT-aided approach.

  1. Operation of high power converters in parallel

    NASA Technical Reports Server (NTRS)

    Decker, D. K.; Inouye, L. Y.

    1993-01-01

    High power converters that are used in space power subsystems are limited in power handling capability due to component and thermal limitations. For applications, such as Space Station Freedom, where multi-kilowatts of power must be delivered to user loads, parallel operation of converters becomes an attractive option when considering overall power subsystem topologies. TRW developed three different unequal power sharing approaches for parallel operation of converters. These approaches, known as droop, master-slave, and proportional adjustment, are discussed and test results are presented.

  2. Commercialization of the land remote sensing system: An examination of mechanisms and issues

    NASA Technical Reports Server (NTRS)

    Cauley, J. K.; Gaelick, C.; Greenberg, J. S.; Logsdon, J.; Monk, T.

    1983-01-01

    In September 1982 the Secretary of Commerce was authorized (by Title II of H.R. 5890 of the 97th Congress) to plan and provide for the management and operation of the civil land remote sensing satellite systems, to provide for user fees, and to plan for the transfer of the ownership and operation of future civil operational land remote sensing satellite systems to the private sector. As part of the planning for transfer, a number of approaches were to be compared including wholly private ownership and operation of the system by an entity competitively selected, mixed government/private ownership and operation, and a legislatively-chartered privately-owned corporation. The results of an analysis and comparison of a limited number of financial and organizational approaches for either transfer of the ownership and operation of the civil operational land remote sensing program to the private sector or government retention are presented.

  3. Mentoring SFRM: A New Approach to International Space Station Flight Control Training

    NASA Technical Reports Server (NTRS)

    Huning, Therese; Barshi, Immanuel; Schmidt, Lacey

    2009-01-01

    The Mission Operations Directorate (MOD) of the Johnson Space Center is responsible for providing continuous operations support for the International Space Station (ISS). Operations support requires flight controllers who are skilled in team performance as well as the technical operations of the ISS. Space Flight Resource Management (SFRM), a NASA adapted variant of Crew Resource Management (CRM), is the competency model used in the MOD. ISS flight controller certification has evolved to include a balanced focus on development of SFRM and technical expertise. The latest challenge the MOD faces is how to certify an ISS flight controller (Operator) to a basic level of effectiveness in 1 year. SFRM training uses a twopronged approach to expediting operator certification: 1) imbed SFRM skills training into all Operator technical training and 2) use senior flight controllers as mentors. This paper focuses on how the MOD uses senior flight controllers as mentors to train SFRM skills.

  4. Modelling of Operative Report Documents for Data Integration into an openEHR-Based Enterprise Data Warehouse.

    PubMed

    Haarbrandt, Birger; Wilschko, Andreas; Marschollek, Michael

    2016-01-01

    In order to integrate operative report documents from two operating room management systems into a data warehouse, we investigated the application of the two-level modelling approach of openEHR to create a shared data model. Based on the systems' analyses, a template consisting of 13 archetypes has been developed. Of these 13 archetypes, 3 have been obtained from the international archetype repository of the openEHR foundation. The remaining 10 archetypes have been newly created. The template was evaluated by an application system expert and through conducting a first test mapping of real-world data from one of the systems. The evaluation showed that by using the two-level modelling approach of openEHR, we succeeded to represent an integrated and shared information model for operative report documents. More research is needed to learn about the limitations of this approach in other data integration scenarios.

  5. Degenerate R-S perturbation theory

    NASA Technical Reports Server (NTRS)

    Hirschfelder, J. O.; Certain, P. R.

    1973-01-01

    A concise, systematic procedure is given for determining the Rayleigh-Schrodinger energies and wave functions of degenerate states to arbitrarily high orders even when the degeneracies of the various states are resolved in arbitrary orders. The procedure is expressed in terms of an iterative cycle in which the energy through the (2n+1)st order is expressed in terms of the partially determined wave function through the n-th order. Both a direct and an operator derivation are given. The two approaches are equivalent and can be transcribed into each other. The direct approach deals with the wave functions (without the use of formal operators) and has the advantage that it resembles the usual treatment of nondegenerate perturbations and maintains close contact with the basic physics. In the operator approach, the wave functions are expressed in terms of infinite order operators which are determined by the successive resolution of the space of the zeroth order functions.

  6. Degenerate RS perturbation theory. [Rayleigh-Schroedinger energies and wave functions

    NASA Technical Reports Server (NTRS)

    Hirschfelder, J. O.; Certain, P. R.

    1974-01-01

    A concise, systematic procedure is given for determining the Rayleigh-Schroedinger energies and wave functions of degenerate states to arbitrarily high orders even when the degeneracies of the various states are resolved in arbitrary orders. The procedure is expressed in terms of an iterative cycle in which the energy through the (2n + 1)-th order is expressed in terms of the partially determined wave function through the n-th order. Both a direct and an operator derivation are given. The two approaches are equivalent and can be transcribed into each other. The direct approach deals with the wave functions (without the use of formal operators) and has the advantage that it resembles the usual treatment of nondegenerate perturbations and maintains close contact with the basic physics. In the operator approach, the wave functions are expressed in terms of infinite-order operators which are determined by the successive resolution of the space of the zeroth-order functions.

  7. The efficacy of modified direct lateral versus posterior approach on gait function and hip muscle strength after primary total hip arthroplasty at 12months follow-up. An explorative randomised controlled trial.

    PubMed

    Rosenlund, Signe; Broeng, Leif; Overgaard, Søren; Jensen, Carsten; Holsgaard-Larsen, Anders

    2016-11-01

    The lateral and the posterior approach are the most commonly used procedures for total hip arthroplasty. Due to the detachment of the hip abductors, lateral approach is claimed to cause reduced hip muscle strength and altered gait pattern. However, this has not been investigated in a randomised controlled trial. The aim was to compare the efficacy of total hip arthroplasty performed by lateral or posterior approach on gait function and hip muscle strength up to 12months post-operatively. We hypothesised that posterior approach would be superior to lateral approach. Forty-seven patients with primary hip osteoarthritis were randomised to total hip arthroplasty with either posterior or lateral approach and evaluated pre-operatively, 3 and 12months post-operatively using 3-dimensional gait analyses as objective measures of gait function, including Gait Deviation Index, temporo-spatial parameters and range of motion. Isometric maximal hip muscle strength in abduction, flexion and extension was also tested. Post-operatively, no between-group difference in gait function was observed. However, both hip abductor and flexor muscle strength improved more in the posterior approach group: -0.20(Nm/kg)[95%CI:-0.4 to 0.0] and -0.20(Nm/kg)[95%CI:-0.4 to 0.0], respectively. Contrary to our first hypothesis, the overall gait function in the posterior approach group did not improve more than in the lateral approach group. However, in agreement with our second hypothesis, patients in the posterior approach group improved more in hip abductor and flexor muscle strength at 12months. Further investigation of the effect of reduced maximal hip muscle strength on functional capacity is needed. ClinicalTrials.gov. No.: NCT01616667. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Robotic and endoscopic transaxillary thyroidectomies may be cost prohibitive when compared to standard cervical thyroidectomy: a cost analysis.

    PubMed

    Cabot, Jennifer C; Lee, Cho Rok; Brunaud, Laurent; Kleiman, David A; Chung, Woong Youn; Fahey, Thomas J; Zarnegar, Rasa

    2012-12-01

    This study presents a cost analysis of the standard cervical, gasless transaxillary endoscopic, and gasless transaxillary robotic thyroidectomy approaches based on medical costs in the United States. A retrospective review of 140 patients who underwent standard cervical, transaxillary endoscopic, or transaxillary robotic thyroidectomy at 2 tertiary centers was conducted. The cost model included operating room charges, anesthesia fee, consumables cost, equipment depreciation, and maintenance cost. Sensitivity analyses assessed individual cost variables. The mean operative times for the standard cervical, transaxillary endoscopic, and transaxillary robotic approaches were 121 ± 18.9, 185 ± 26.0, and 166 ± 29.4 minutes, respectively. The total cost for the standard cervical, transaxillary endoscopic, and transaxillary robotic approaches were $9,028 ± $891, $12,505 ± $1,222, and $13,670 ± $1,384, respectively. Transaxillary approaches were significantly more expensive than the standard cervical technique (standard cervical/transaxillary endoscopic, P < .0001; standard cervical/transaxillary robotic, P < .0001; and transaxillary endoscopic/transaxillary robotic, P = .001). The transaxillary and standard cervical techniques became equivalent in cost when transaxillary endoscopic operative time decreased to 111 minutes and transaxillary robotic operative time decreased to 68 minutes. Increasing the case load did not resolve the cost difference. Transaxillary endoscopic and transaxillary robotic thyroidectomies are significantly more expensive than the standard cervical approach. Decreasing operative times reduces this cost difference. The greater expense may be prohibitive in countries with a flat reimbursement schedule. Copyright © 2012 Mosby, Inc. All rights reserved.

  9. Quantization and Quantum-Like Phenomena: A Number Amplitude Approach

    NASA Astrophysics Data System (ADS)

    Robinson, T. R.; Haven, E.

    2015-12-01

    Historically, quantization has meant turning the dynamical variables of classical mechanics that are represented by numbers into their corresponding operators. Thus the relationships between classical variables determine the relationships between the corresponding quantum mechanical operators. Here, we take a radically different approach to this conventional quantization procedure. Our approach does not rely on any relations based on classical Hamiltonian or Lagrangian mechanics nor on any canonical quantization relations, nor even on any preconceptions of particle trajectories in space and time. Instead we examine the symmetry properties of certain Hermitian operators with respect to phase changes. This introduces harmonic operators that can be identified with a variety of cyclic systems, from clocks to quantum fields. These operators are shown to have the characteristics of creation and annihilation operators that constitute the primitive fields of quantum field theory. Such an approach not only allows us to recover the Hamiltonian equations of classical mechanics and the Schrödinger wave equation from the fundamental quantization relations, but also, by freeing the quantum formalism from any physical connotation, makes it more directly applicable to non-physical, so-called quantum-like systems. Over the past decade or so, there has been a rapid growth of interest in such applications. These include, the use of the Schrödinger equation in finance, second quantization and the number operator in social interactions, population dynamics and financial trading, and quantum probability models in cognitive processes and decision-making. In this paper we try to look beyond physical analogies to provide a foundational underpinning of such applications.

  10. Climate Change Adaptation in the Western U.S.: the Case for Dynamic Rule Curves in Water Resources Management

    NASA Astrophysics Data System (ADS)

    Lee, S.; Hamlet, A. F.; Burges, S. J.

    2008-12-01

    Climate change in the Western U.S. will bring systematic hydrologic changes affecting many water resources systems. Successful adaptation to these changes, which will be ongoing through the 21st century, will require the 'rebalancing' of competing system objectives such as water supply, flood control, hydropower production, and environmental services in response to hydrologic (and other) changes. Although fixed operating policies for the operation of reservoirs has been a traditional approach to water management in the 20th century, the rapid pace of projected climate shifts (~0.5 F per decade), and the prohibitive costs of recursive policy intervention to mitigate impacts, suggest that more sophisticated approaches will be needed to cope with climate change on a long term basis. The use of 'dynamic rule curves' is an approach that maintains some of the key characteristics of current water management practice (reservoir rule curves) while avoiding many of the fundamental drawbacks of traditional water resources management strategies in a non-stationary climate. In this approach, water resources systems are optimized for each operational period using ensemble streamflow and/or water demand forecasts. The ensemble of optimized reservoir storage traces are then analyzed to produce a set of unique reservoir rule curves for each operational period reflecting the current state of the system. The potential advantage of this approach is that hydrologic changes associated with climate change (such as systematically warmer temperatures) can be captured explicitly in operational hydrologic forecasts, which would in turn inform the optimized reservoir management solutions, creating water resources systems that are largely 'self tending' as the climate system evolves. Furthermore, as hydrologic forecasting systems improve (e.g. in response to improved ENSO forecasting or other scientific advances), so does the performance of reservoir operations. An example of the approach is given for flood control in the Columbia River basin.

  11. Real-time Ensemble Flow Forecasts for a 2017 Mock Operation Test Trial of Forecast Informed Reservoir Operations for Lake Mendocino in Mendocino County, California

    NASA Astrophysics Data System (ADS)

    Delaney, C.; Mendoza, J.; Jasperse, J.; Hartman, R. K.; Whitin, B.; Kalansky, J.

    2017-12-01

    Forecast informed reservoir operations (FIRO) is a methodology that incorporates short to mid-range precipitation and flow forecasts to inform the flood operations of reservoirs. The Ensemble Forecast Operations (EFO) alternative is a probabilistic approach of FIRO that incorporates 15-day ensemble streamflow predictions (ESPs) made by NOAA's California-Nevada River Forecast Center (CNRFC). With the EFO approach, release decisions are made to manage forecasted risk of reaching critical operational thresholds. A water management model was developed for Lake Mendocino, a 111,000 acre-foot reservoir located near Ukiah, California, to conduct a mock operation test trial of the EFO alternative for 2017. Lake Mendocino is a dual use reservoir, which is owned and operated for flood control by the United States Army Corps of Engineers and is operated for water supply by the Sonoma County Water Agency. Due to recent changes in the operations of an upstream hydroelectric facility, this reservoir has suffered from water supply reliability issues since 2007. The operational trial utilized real-time ESPs prepared by the CNRFC and observed flow information to simulate hydrologic conditions in Lake Mendocino and a 50-mile downstream reach of the Russian River to the City of Healdsburg. Results of the EFO trial demonstrate a 6% increase in reservoir storage at the end of trial period (May 10) relative to observed conditions. Additionally, model results show no increase in flows above flood stage for points downstream of Lake Mendocino. Results of this investigation and other studies demonstrate that the EFO alternative may be a viable flood control operations approach for Lake Mendocino and warrants further investigation through additional modeling and analysis.

  12. SimSup's Loop: A Control Theory Approach to Spacecraft Operator Training

    NASA Technical Reports Server (NTRS)

    Owens, Brandon Dewain; Crocker, Alan R.

    2015-01-01

    Immersive simulation is a staple of training for many complex system operators, including astronauts and ground operators of spacecraft. However, while much has been written about simulators, simulation facilities, and operator certification programs, the topic of how one develops simulation scenarios to train a spacecraft operator is relatively understated in the literature. In this paper, an approach is presented for using control theory as the basis for developing the immersive simulation scenarios for a spacecraft operator training program. The operator is effectively modeled as a high level controller of lower level hardware and software control loops that affect a select set of system state variables. Simulation scenarios are derived from a STAMP-based hazard analysis of the operator's high and low level control loops. The immersive simulation aspect of the overall training program is characterized by selecting a set of scenarios that expose the operator to the various inadequate control actions that stem from control flaws and inadequate control executions in the different sections of the typical control loop. Results from the application of this approach to the Lunar Atmosphere and Dust Environment Explorer (LADEE) mission are provided through an analysis of the simulation scenarios used for operator training and the actual anomalies that occurred during the mission. The simulation scenarios and inflight anomalies are mapped to specific control flaws and inadequate control executions in the different sections of the typical control loop to illustrate the characteristics of anomalies arising from the different sections of the typical control loop (and why it is important for operators to have exposure to these characteristics). Additionally, similarities between the simulation scenarios and inflight anomalies are highlighted to make the case that the simulation scenarios prepared the operators for the mission.

  13. NASA JPL Distributed Systems Technology (DST) Object-Oriented Component Approach for Software Inter-Operability and Reuse

    NASA Technical Reports Server (NTRS)

    Hall, Laverne; Hung, Chaw-Kwei; Lin, Imin

    2000-01-01

    The purpose of this paper is to provide a description of NASA JPL Distributed Systems Technology (DST) Section's object-oriented component approach to open inter-operable systems software development and software reuse. It will address what is meant by the terminology object component software, give an overview of the component-based development approach and how it relates to infrastructure support of software architectures and promotes reuse, enumerate on the benefits of this approach, and give examples of application prototypes demonstrating its usage and advantages. Utilization of the object-oriented component technology approach for system development and software reuse will apply to several areas within JPL, and possibly across other NASA Centers.

  14. An extended transfer operator approach to identify separatrices in open flows

    NASA Astrophysics Data System (ADS)

    Lünsmann, Benedict; Kantz, Holger

    2018-05-01

    Vortices of coherent fluid volume are considered to have a substantial impact on transport processes in turbulent media. Yet, due to their Lagrangian nature, detecting these structures is highly nontrivial. In this respect, transfer operator approaches have been proven to provide useful tools: Approximating a possibly time-dependent flow as a discrete Markov process in space and time, information about coherent structures is contained in the operator's eigenvectors, which is usually extracted by employing clustering methods. Here, we propose an extended approach that couples surrounding filaments using "mixing boundary conditions" and focuses on the separation of the inner coherent set and embedding outer flow. The approach refrains from using unsupervised machine learning techniques such as clustering and uses physical arguments by maximizing a coherence ratio instead. We show that this technique improves the reconstruction of separatrices in stationary open flows and succeeds in finding almost-invariant sets in periodically perturbed flows.

  15. Hercules Single-Stage Reusable Vehicle (HSRV) Operating Base

    NASA Technical Reports Server (NTRS)

    Moon, Michael J.; McCleskey, Carey M.

    2017-01-01

    Conceptual design for the layout of lunar-planetary surface support systems remains an important area needing further master planning. This paper explores a structured approach to organize the layout of a Mars-based site equipped for routinely flying a human-scale reusable taxi system. The proposed Hercules Transportation System requires a surface support capability to sustain its routine, affordable, and dependable operation. The approach organizes a conceptual Hercules operating base through functional station sets. The station set approach will allow follow-on work to trade design approaches and consider technologies for more efficient flow of material, energy, and information at future Mars bases and settlements. The station set requirements at a Mars site point to specific capabilities needed. By drawing from specific Hercules design characteristics, the technology requirements for surface-based systems will come into greater focus. This paper begins a comprehensive process for documenting functional needs, architectural design methods, and analysis techniques necessary for follow-on concept studies.

  16. The impact of operative approach on outcome of surgery for gastro-oesophageal tumours.

    PubMed

    Suttie, Stuart A; Li, Alan Gk; Quinn, Martha; Park, Kenneth Gm

    2007-08-20

    The choice of operation for tumours at or around the gastro-oesophageal junction remains controversial with little evidence to support one technique over another. This study examines the prevalence of margin involvement and nodal disease and their impact on outcome following three surgical approaches (Ivor Lewis, transhiatal and left thoraco-laparotomy) for these tumours. A retrospective analysis was conducted of patients undergoing surgery for distal oesophageal and gastro-oesophageal junction tumours by a single surgeon over ten years. Comparisons were undertaken in terms of tumour clearance, nodal yield, postoperative morbidity, mortality, and median survival. All patients were followed up until death or the end of the data collection (mean follow up 33.2 months). A total of 104 patients were operated on of which 102 underwent resection (98%). Median age was 64.1 yrs (range 32.1-79.4) with 77 males and 25 females. Procedures included 29 Ivor Lewis, 31 transhiatal and 42 left-thoraco-laparotomies. Postoperative mortality was 2.9% and median survival 23 months. Margin involvement was 24.1% (two distal, one proximal and 17 circumferential margins). Operative approach had no significant effect on nodal clearance, margin involvement, postoperative mortality or morbidity and survival. Lymph node positive disease had a significantly worse median survival of 15.8 months compared to 39.7 months for node negative (p = 0.007), irrespective of approach. Surgical approach had no effect on postoperative mortality, circumferential tumour, nodal clearance or survival. This suggests that the choice of operative approach for tumours at the gastro-oesophageal junction may be based on the individual patient and tumour location rather than surgical dogma.

  17. Information operator approach applied to the retrieval of vertical distributions of atmospheric constituents from ground-based FTIR measurements

    NASA Astrophysics Data System (ADS)

    Senten, Cindy; de Mazière, Martine; Vanhaelewyn, Gauthier; Vigouroux, Corinne; Delmas, Robert

    2010-05-01

    The retrieval of information about the vertical distribution of an atmospheric absorber from high spectral resolution ground-based Fourier Transform infrared (FTIR) solar absorption spectra is an important issue in remote sensing. A frequently used technique at present is the optimal estimation method. This work introduces the application of an alternative method, namely the information operator approach (Doicu et al., 2007; Hoogen et al., 1999), for extracting the available information from such FTIR measurements. This approach has been implemented within the well-known retrieval code SFIT2, by adapting the optimal estimation method such as to take into account only the significant contributions to the solution. In particular, we demonstrate the feasibility of the method when applied to ground-based FTIR spectra taken at the southern (sub)tropical site Ile de La Réunion (21° S, 55° E) in 2007. A thorough comparison has been made between the retrieval results obtained with the original optimal estimation method and the ones obtained with the information operator approach, regarding profile and column stability, information content and corresponding full error budget evaluation. This has been done for the target species ozone (O3), methane (CH4), nitrous oxide (N2O), and carbon monoxide (CO). It is shown that the information operator approach performs well and is capable of achieving the same accuracy as optimal estimation, with a gain of stability and with the additional advantage of being less sensitive to the choice of a priori information as well as to the actual signal-to-noise ratio. Keywords: ground-based FTIR, solar absorption spectra, greenhouse gases, information operator approach References Doicu, A., Hilgers, S., von Bargen, A., Rozanov, A., Eichmann, K.-U., von Savigny, C., and Burrows, J.P.: Information operator approach and iterative regularization methods for atmospheric remote sensing, J. Quant. Spectrosc. Radiat. Transfer, 103, 340-350, 2007. Hoogen, R., Rozanov, V.V., and Burrows, J.P.: Ozone profiles from GOME satellite data: description and first validation, J. Geophys. Res., 104(D7), 8263-8280, 1999.

  18. Alternative Approaches to Mission Control Automation at NASA's Goddard Space Flight Center

    NASA Technical Reports Server (NTRS)

    Rackley, Michael; Cooter, Miranda; Davis, George; Mackey, Jennifer

    2001-01-01

    To meet its objective of reducing operations costs without incurring a corresponding increase in risk, NASA is seeking new methods to automate mission operations. This paper examines the state of the art in automating ground operations for space missions. A summary of available technologies and methods for automating mission operations is provided. Responses from interviews with several space mission FOTs (Flight Operations Teams) to assess the degree and success of those technologies and methods implemented are presented. Mission operators that were interviewed approached automation using different tools and methods resulting in varying degrees of success - from nearly completely automated to nearly completely manual. Two key criteria for successful automation are the active participation of the FOT in the planning, designing, testing, and implementation of the system and the relative degree of complexity of the mission.

  19. An Operational evaluation of head up displays for civil transport operations. NASA/FAA phase 3 report

    NASA Technical Reports Server (NTRS)

    Lauber, J. K.; Bray, R. S.; Harrison, R. L.; Hemingway, J. C.; Scott, B. C.

    1982-01-01

    The advantages and disadvantages of head-up displays (HUDs) in commercial jet transport approach and landing operations was evaluated. Ten airline captains currently qualified in the B-727 aircraft flew a series of instrument landing system (ILS) and nonprecision approaches in a motion base simulator using both a flight director HUD concept and a flightpath HUD concept as well as conventional head-down instruments under a variety of environmental and operational conditions to assess: (1) the potential benefits of these HUDs in airline operations; (2) problems which might be associated with their use; and (3) flight crew training requirements and flight crew operating procedures suitable for use with the HUDs. Results are presented in terms of objective simulator based performance measures, subject pilot opinion and rating data, and observer data.

  20. A Code Generation Approach for Auto-Vectorization in the Spade Compiler

    NASA Astrophysics Data System (ADS)

    Wang, Huayong; Andrade, Henrique; Gedik, Buğra; Wu, Kun-Lung

    We describe an auto-vectorization approach for the Spade stream processing programming language, comprising two ideas. First, we provide support for vectors as a primitive data type. Second, we provide a C++ library with architecture-specific implementations of a large number of pre-vectorized operations as the means to support language extensions. We evaluate our approach with several stream processing operators, contrasting Spade's auto-vectorization with the native auto-vectorization provided by the GNU gcc and Intel icc compilers.

  1. Using Advanced Tabu Search Approaches to Perform Enhanced Air Mobility Command Operational Airlift Analyses

    DTIC Science & Technology

    2009-02-28

    2, No. 2, 2007, pp. 156-172. 21. Lambert, G.,J.W. Barnes, and D. Van Veldhuizen ,, "A Tabu Search Approach to the Strategic Airlift Problem...Industrial Engineering, accepted, to appear 2009, pp 1 -86, published by Taylor and Francis/CRC Press. 27. Roesener, A., J. W. Barnes, J. Moore, D. Van ... Veldhuizen , "An Advanced Tabu Search Approach To The Static Airlift Loading Problem," Military Operations Research, 2007, (in second review). 28. Burks

  2. Integrated orbital servicing study follow-on. Volume 2: Technical analysis and system design

    NASA Technical Reports Server (NTRS)

    1978-01-01

    In-orbit service functional and physical requirements to support both low and high Earth orbit servicing/maintenance operations were defined, an optimum servicing system configuration was developed and mockups and early prototype hardware were fabricated to demonstrate and validate the concepts selected. Significant issues addressed include criteria for concept selection; representative mission equipment and approaches to their design for serviceability; significant serviceable spacecraft design aspects; servicer mechanism operation in one-g; approaches for the demonstration/simulation; and service mechanism structure design approach.

  3. Robot-assisted approach improves surgical outcomes in obese patients undergoing partial nephrectomy.

    PubMed

    Malkoc, Ercan; Maurice, Matthew J; Kara, Onder; Ramirez, Daniel; Nelson, Ryan J; Caputo, Peter A; Mouracade, Pascal; Stein, Robert; Kaouk, Jihad H

    2017-02-01

    To assess the impact of approach on surgical outcomes in otherwise healthy obese patients undergoing partial nephrectomy for small renal masses. Using our institutional partial nephrectomy database, we abstracted data on otherwise healthy (Charlson comorbidity score ≤1 and bilateral kidneys), obese patients (body mass index >30 kg/m 2 ) with small renal masses (<4 cm) treated between 2011 and 2015. The primary outcomes were intra-operative transfusion, operating time, length of hospital stay (LOS), and postoperative complications. The association between approach, open (OPN) vs robot-assisted partial nephrectomy (RAPN), and outcomes was assessed by univariable and multivariable logistic regression analyses. Covariates included age, gender, obesity severity, tumour size and tumour complexity. Of 237 obese patients undergoing partial nephrectomy, 25% underwent OPN and 75% underwent RAPN. Apart from larger tumour size in the OPN group (2.8 vs 2.5 cm; P = 0.02), there was no significant difference between groups. The rate of intra-operative blood transfusion (1.1 vs 10%; P = 0.01), the median operating time (180 vs 207 min; P < 0.01) and the median ischaemia time (19.5 vs 27 min; P < 0.01) were all greater for OPN. The LOS was significantly shorter for RAPN (3 vs 4 days; P < 0.01). While the overall complication rate was higher for OPN (15.8 vs 31.7%; P < 0.01), major complications were not significantly different (5.6 vs 1.7%; P = 0.20). On multivariable analyses, OPN independently predicted longer operating time, longer length of stay, and more overall complications. At a high-volume centre, the robot-assisted approach offers less blood transfusion, shorter operating time, faster recovery, and fewer peri-operative complications compared with the open approach in obese patients undergoing partial nephrectomy for small renal masses. In this setting, RAPN may be a preferable treatment option. © 2016 The Authors BJU International © 2016 BJU International Published by John Wiley & Sons Ltd.

  4. Implementation of a near-zero fluoroscopy approach in interventional electrophysiology: impact of operator experience.

    PubMed

    Wannagat, Severin; Loehr, Lena; Lask, Sebastian; Völk, Katharina; Karaköse, Tamer; Özcelik, Cemil; Mügge, Andreas; Wutzler, Alexander

    2018-04-01

    Catheter ablation is performed under fluoroscopic guidance. Reduction of radiation dose for patients and staff is emphasized by current recommendations. Previous studies have shown that lower operator experience leads to increased radiation dose. On the other hand, less experienced operators may depend even more on fluoroscopic guidance. Our study aimed to evaluate feasibility and efficacy of a non-fluoroscopic approach in different training levels. From January 2017, a near-zero fluoroscopy approach was established in two centers. Four operators (beginner, 1st year fellow, 2nd year fellow, expert) were instructed to perform the complete procedure with the use of a 3-D mapping system without fluoroscopy. A historical cohort that underwent procedures with fluoroscopy use served as control group. Dose area product (DPA), procedure duration, acute procedural success, and complications were compared between the groups and for each operator. Procedures were performed in 157 patients. The first 100 patients underwent procedures with fluoroscopic guidance, the following 57 procedures were performed with the near-zero fluoroscopy approach. The results show a significant reduction in DPA for all operators immediately after implementation of the near-zero fluoroscopy protocol (control 637 ± 611 μGy/m 2 ; beginner 44.1 ± 79.5 μGy/m 2 , p = 0.002; 1st year fellow 24.3 ± 46.4.5 μGy/m 2 , p = 0.001; 2nd year fellow 130.3 ± 233.3 μGy/m 2 , p = 0.003; expert 9.3 ± 37.4 μGy/m 2 , P < 0.001). Procedure duration, acute success, and complications were not significantly different between the groups. Our results show a 90% reduction of DPA shortly after implementation of a near-zero fluoroscopy approach in interventional electrophysiology even in operators in training.

  5. [Alternative approaches in thyroid surgery].

    PubMed

    Maurer, E; Wächter, S; Bartsch, D K

    2017-08-01

    In thyroid surgery multiple different cervical minimally invasive (partly endoscopically assisted) and extracervical endoscopic (partly robot-assisted) approaches have been developed in the last 20 years. The aim of all these alternative approaches to the thyroid gland is optimization of the cosmetic result. The indications for the use of alternative and conventional approaches are principally the same. Important requirements for the use of alternative methods are nevertheless a broad experience in conventional thyroid operations of the thyroid and adequate patient selection under consideration of the size of the thyroid and the underlying pathology. Contraindications for the use of alternative approaches are a large size of the thyroid gland including local symptoms, advanced carcinomas, reoperations and previous radiations of the anterior neck. The current article gives an overview of the clinically implemented alternative approaches for thyroid surgery. Of those the majority must still be considered as experimental. The alternative approaches to the thyroid gland can be divided in cervical minimally invasive, extracervical endosopic (robot-assisted) and transoral operations (natural orifice transluminal endoscopic surgery, NOTES). Since conventional thyroid operations are standardized procedures with low complication rates, alternative approaches to the thyroid gland are considered critically in Germany. The request for a perfect cosmetic result should not overweigh patients' safety. Only a few alternative approaches (e. g. MIVAT, RAT) can yet be considered as a safe addition in experienced hands in highly selected patients.

  6. The Virtual Mission Operations Center

    NASA Technical Reports Server (NTRS)

    Moore, Mike; Fox, Jeffrey

    1994-01-01

    Spacecraft management is becoming more human intensive as spacecraft become more complex and as operations costs are growing accordingly. Several automation approaches have been proposed to lower these costs. However, most of these approaches are not flexible enough in the operations processes and levels of automation that they support. This paper presents a concept called the Virtual Mission Operations Center (VMOC) that provides highly flexible support for dynamic spacecraft management processes and automation. In a VMOC, operations personnel can be shared among missions, the operations team can change personnel and their locations, and automation can be added and removed as appropriate. The VMOC employs a form of on-demand supervisory control called management by exception to free operators from having to actively monitor their system. The VMOC extends management by exception, however, so that distributed, dynamic teams can work together. The VMOC uses work-group computing concepts and groupware tools to provide a team infrastructure, and it employs user agents to allow operators to define and control system automation.

  7. Perhaps More Consideration of Pavlovian–Operant Interaction May Improve the Clinical Efficacy of Behaviorally Based Drug Treatment Programs

    PubMed Central

    Troisi, Joseph R.

    2014-01-01

    Drug abuse remains costly. Drug-related cues can evoke cue-reactivity and craving, contributing to relapse. The Pavlovian extinction-based cue-exposure therapy (CET) has not been very successful in treating drug abuse. A functional operant analysis of complex rituals involved in CET is outlined and reinterpreted as an operant heterogeneous chain maintained by observing responses, conditioned reinforcers, and discriminative stimuli. It is further noted that operant functions are not predicated on Pavlovian processes but can be influenced by them in contributing to relapse; several empirical studies from the animal and human literature highlight this view. Cue-reactivity evoked by Pavlovian processes is conceptualized as an operant establishing/motivating operation. CET may be more effective in incorporating an operant-based approach that takes into account the complexity of Pavlovian–operant interaction. Extinction of the operant chain coupled with the shaping of alternative behaviors is proposed as an integrated therapy. It is proposed that operant-based drug abuse treatments (contingency management, voucher programs, and the therapeutic work environment) might consider incorporating cue-reactivity, as establishing/motivating operations, to increase long-term success—a hybrid approach based on Pavlovian–operant interaction. PMID:25346551

  8. Perhaps More Consideration of Pavlovian-Operant Interaction May Improve the Clinical Efficacy of Behaviorally Based Drug Treatment Programs.

    PubMed

    Troisi, Joseph R

    2013-01-01

    Drug abuse remains costly. Drug-related cues can evoke cue-reactivity and craving, contributing to relapse. The Pavlovian extinction-based cue-exposure therapy (CET) has not been very successful in treating drug abuse. A functional operant analysis of complex rituals involved in CET is outlined and reinterpreted as an operant heterogeneous chain maintained by observing responses, conditioned reinforcers, and discriminative stimuli. It is further noted that operant functions are not predicated on Pavlovian processes but can be influenced by them in contributing to relapse; several empirical studies from the animal and human literature highlight this view. Cue-reactivity evoked by Pavlovian processes is conceptualized as an operant establishing/motivating operation. CET may be more effective in incorporating an operant-based approach that takes into account the complexity of Pavlovian-operant interaction. Extinction of the operant chain coupled with the shaping of alternative behaviors is proposed as an integrated therapy. It is proposed that operant-based drug abuse treatments (contingency management, voucher programs, and the therapeutic work environment) might consider incorporating cue-reactivity, as establishing/motivating operations, to increase long-term success-a hybrid approach based on Pavlovian-operant interaction.

  9. Evaluation and Management of Traumatic Diaphragmatic Injuries: A Practice Management Guideline from the Eastern Association for the Surgery of Trauma.

    PubMed

    McDonald, Amy A; Robinson, Bryce R H; Alarcon, Louis; Bosarge, Patrick L; Dorion, Heath; Haut, Elliott R; Juern, Jeremy; Madbak, Firas; Reddy, Srinivas; Weiss, Patricia; Como, John J

    2018-04-02

    Traumatic diaphragm injuries (TDI) pose both diagnostic and therapeutic challenges in both the acute and chronic phases. There are no published practice management guidelines to date for TDI. We aim to formulate a practice management guideline for TDI using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. The working group formulated five Patient, Intervention, Comparator, Outcome (PICO) questions regarding the following topics: 1) diagnostic approach (laparoscopy vs. computed tomography); 2) non-operative management of penetrating right-sided injuries; 3) surgical approach (abdominal or thoracic) for acute TDI, including 4) the use of laparoscopy; and 5) surgical approach (abdominal or thoracic) for delayed TDI. A systematic review was undertaken and last updated December 2016. RevMan 5 (Cochran Collaboration) and GRADEpro (Grade Working Group) software were utilized. Recommendations were voted on by working group members. Consensus was obtained for each recommendation. A total of 56 articles were utilized to formulate the recommendations. Most studies were retrospective case series with variable reporting of outcomes measures and outcomes frequently not stratified to intervention or comparator. The overall quality of the evidence was very low for all PICOs. Therefore, only conditional recommendations could be made. Recommendations were made in favor of laparoscopy over CT for diagnosis, non-operative vs. operative approach for right-sided penetrating injuries, abdominal vs. thoracic approach for acute TDI, and laparoscopy (with the appropriate skill set and resources) vs. open approach for isolated TDI. No recommendation could be made for the preferred operative approach for delayed TDI. Very low-quality evidence precluded any strong recommendations. Further study of the diagnostic and therapeutic approaches to TDI is warranted. Guideline LEVEL OF EVIDENCE: 4.

  10. Improving Minimally Invasive Adrenalectomy: Selection of Optimal Approach and Comparison of Outcomes.

    PubMed

    Lairmore, Terry C; Folek, Jessica; Govednik, Cara M; Snyder, Samuel K

    2016-07-01

    Minimally invasive adrenalectomy is commonly performed by either a transperitoneal laparoscopic (TLA) or posterior retroperitoneoscopic (PRA) approach. Our group described the technique for robot-assisted PRA (RAPRA) in 2010. Few studies are available that directly compare outcomes between the available operative approaches. We reviewed our results for minimally invasive adrenalectomy using the three different approaches over a 10-year period. Between January 2005 and April 2015, 160 minimally invasive adrenalectomies were performed. Clinicopathologic data were prospectively collected and retrospectively analyzed. The primary endpoints evaluated were operative time, blood loss, length of stay (LOS), and morbidity. The study included 67 TLA, 76 PRA, and 17 RAPRA procedures. Tumor size for PRA/RAPRA was smaller than for patients undergoing TLA (2.38 vs 3.6 cm, p ≤ 0.0001). Procedure time was shorter for PRA versus TLA (133.3 vs 152.8 min, p = 0.0381), as was LOS (1.85 vs 2.82 days, p = 0.0145). Procedure time was longer in RAPRA versus TLA/PRA (177 vs 153/133 min, p = 0.008), but LOS was significantly decreased (1.53 vs 2.82/1.85 days, p = 0.004). Minimally invasive adrenalectomy is associated with expected excellent outcomes regardless of approach. In our series, the posterior approach is associated with decreased operative time and LOS. Robotic technology provides potential advantages for the surgeon at the expense of more complex setup requirements and costs. Further study is required to demonstrate clear benefit of one surgical approach. Utilization of the entire spectrum of available operative techniques can allow for selection of the optimal approach based on individual patient factors.

  11. COTS-based OO-component approach for software inter-operability and reuse (software systems engineering methodology)

    NASA Technical Reports Server (NTRS)

    Yin, J.; Oyaki, A.; Hwang, C.; Hung, C.

    2000-01-01

    The purpose of this research and study paper is to provide a summary description and results of rapid development accomplishments at NASA/JPL in the area of advanced distributed computing technology using a Commercial-Off--The-Shelf (COTS)-based object oriented component approach to open inter-operable software development and software reuse.

  12. The Aeronautical Data Link: Taxonomy, Architectural Analysis, and Optimization

    NASA Technical Reports Server (NTRS)

    Morris, A. Terry; Goode, Plesent W.

    2002-01-01

    The future Communication, Navigation, and Surveillance/Air Traffic Management (CNS/ATM) System will rely on global satellite navigation, and ground-based and satellite based communications via Multi-Protocol Networks (e.g. combined Aeronautical Telecommunications Network (ATN)/Internet Protocol (IP)) to bring about needed improvements in efficiency and safety of operations to meet increasing levels of air traffic. This paper will discuss the development of an approach that completely describes optimal data link architecture configuration and behavior to meet the multiple conflicting objectives of concurrent and different operations functions. The practical application of the approach enables the design and assessment of configurations relative to airspace operations phases. The approach includes a formal taxonomic classification, an architectural analysis methodology, and optimization techniques. The formal taxonomic classification provides a multidimensional correlation of data link performance with data link service, information protocol, spectrum, and technology mode; and to flight operations phase and environment. The architectural analysis methodology assesses the impact of a specific architecture configuration and behavior on the local ATM system performance. Deterministic and stochastic optimization techniques maximize architectural design effectiveness while addressing operational, technology, and policy constraints.

  13. A review on prognostics approaches for remaining useful life of lithium-ion battery

    NASA Astrophysics Data System (ADS)

    Su, C.; Chen, H. J.

    2017-11-01

    Lithium-ion (Li-ion) battery is a core component for various industrial systems, including satellite, spacecraft and electric vehicle, etc. The mechanism of performance degradation and remaining useful life (RUL) estimation correlate closely to the operating state and reliability of the aforementioned systems. Furthermore, RUL prediction of Li-ion battery is crucial for the operation scheduling, spare parts management and maintenance decision for such kinds of systems. In recent years, performance degradation prognostics and RUL estimation approaches have become a focus of the research concerning with Li-ion battery. This paper summarizes the approaches used in Li-ion battery RUL estimation. Three categories are classified accordingly, i.e. model-based approach, data-based approach and hybrid approach. The key issues and future trends for battery RUL estimation are also discussed.

  14. Transoral Open Reduction for Subcondylar Fractures of the Mandible Using an Angulated Screwdriver System.

    PubMed

    Nam, Seung Min; Kim, Yong Bae; Cha, Han Gyu; Wee, Syeo Young; Choi, Chang Yong

    2015-09-01

    The management of subcondylar mandibular fractures has been a matter of controversy. Although closed reduction is the most useful method, it can be difficult to achieve anatomical reduction with this technique compared with open reduction and internal fixation (ORIF). Most surgeons prefer to treat subcondylar fractures by extraoral approaches rather than intraoral approaches because extraoral approaches provide good visualization of the operative field. The retromandibular, submandibular, and perilobular approaches are commonly performed in the treatment of displaced condylar or subcondylar fractures and that the functional results of these treatments are good. However, extraoral approaches have a high rate of surgical complications such as salivary fistula formation, visible scarring, and facial nerve injury, compared with intraoral approaches. Therefore, this clinical study evaluated the clinical results of ORIF for mandibular subcondylar fractures through a transoral approach using an angulated screwdriver system without endoscopic assistance. A study was conducted between March 2011 and October 2012. Eleven patients with subcondylar fractures of the mandible were treated through a transoral approach using an angulated screwdriver. There were 10 male patients and 1 female patient aged 21 to 72 years (mean, 38 years). Nine patients had a symphyseal or parasymphyseal fracture, and 2 patients had isolated subcondylar fractures of the mandible. Eleven patients with subcondylar fractures of the mandible were treated with a transoral approach using an angulated screwdriver. The subcondylar fracture was on the left side in 6 patients and on the right in 5. All patients achieved satisfactory ranges of temporomandibular joint movement with an interincisal distance of more than 40 mm without deviation and stable individual centric occlusion. The maximum operation duration was 165 minutes, and the average duration of ORIF was 97 minutes. The association between the operation duration and the number of operations was statistically significant. Our clinical study shows that subcondylar fractures of the mandible can be treated using an angulated screwdriver system through a transoral approach and that this technique provides reliable, satisfactory, and safe clinical outcomes.

  15. Safely Enabling UAS Operations in Low-Altitude Airspace

    NASA Technical Reports Server (NTRS)

    Kopardekar, Parimal H.

    2016-01-01

    Flexibility where possible, and structure where necessary. Consider the needs of national security, safe airspace operations, economic opportunities, and emerging technologies. Risk-based approach based on population density, assets on the ground, density of operations, etc. Digital, virtual, dynamic, and as needed UTM services to manage operations.

  16. Efficacy of Effects Based Operations on Maoist COIN Operations in India

    DTIC Science & Technology

    2012-04-30

    14, SUBJECT TERMS 15. NUMBER OF PAGES. 49 Naxalite Insurgency, Effects Based Approach/Effects Based Operations, Counterinsurgency in India 16...MAOIST COIN OPERATIONS IN INDIA SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF MILJTARY STUDIES MAJOR PRAMOD GAHLOT

  17. 75 FR 32495 - Operating Fund Subsidies Allocation Formula

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-08

    ... DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT [Docket No. FR-5376-N-49] Operating Fund Subsidies... establishes an Operating Fund for the purpose of making assistance available to public housing agencies (PHAs) which assistance is determined using a formula approach under the Operating Fund Program. PHAs compute...

  18. Measuring Information Technology Performance: Operational Efficiency and Operational Effectiveness

    ERIC Educational Resources Information Center

    Moore, Annette G.

    2012-01-01

    This dissertation provides a practical approach for measuring operational efficiency and operational effectiveness for IT organizations introducing the ITIL process framework. The intent of the study was to assist Chief Information Officers (CIOs) in explaining the impact of introducing the Information Technology Infrastructure Library (ITIL)…

  19. Approach for Autonomous Control of Unmanned Aerial Vehicle Using Intelligent Agents for Knowledge Creation

    NASA Technical Reports Server (NTRS)

    Dufrene, Warren R., Jr.

    2004-01-01

    This paper describes the development of a planned approach for Autonomous operation of an Unmanned Aerial Vehicle (UAV). A Hybrid approach will seek to provide Knowledge Generation thru the application of Artificial Intelligence (AI) and Intelligent Agents (IA) for UAV control. The application of many different types of AI techniques for flight will be explored during this research effort. The research concentration will be directed to the application of different AI methods within the UAV arena. By evaluating AI approaches, which will include Expert Systems, Neural Networks, Intelligent Agents, Fuzzy Logic, and Complex Adaptive Systems, a new insight may be gained into the benefits of AI techniques applied to achieving true autonomous operation of these systems thus providing new intellectual merit to this research field. The major area of discussion will be limited to the UAV. The systems of interest include small aircraft, insects, and miniature aircraft. Although flight systems will be explored, the benefits should apply to many Unmanned Vehicles such as: Rovers, Ocean Explorers, Robots, and autonomous operation systems. The flight system will be broken down into control agents that will represent the intelligent agent approach used in AI. After the completion of a successful approach, a framework of applying a Security Overseer will be added in an attempt to address errors, emergencies, failures, damage, or over dynamic environment. The chosen control problem was the landing phase of UAV operation. The initial results from simulation in FlightGear are presented.

  20. Engineering approach for cost effective operation of industrial pump systems

    NASA Astrophysics Data System (ADS)

    Krickis, O.; Oleksijs, R.

    2017-10-01

    Power plants operators are persuaded to operate the main equipment such as centrifugal pumps in economically effective way. The operation of pump sets of district heating network at power plants should be done according to prescriptions of the original equipment manufacturer with further implementation of these requirements to distributed control system of the plant. In order to operate industrial pump sets with a small number of malfunctions is necessary to control the duty point of pump sets in H-Q coordinates, which could be complex task in some installations. Alternatively, pump operation control could be organized in H-n (head vs rpm) coordinates, utilizing pressure transmitters in pressure pipeline and value of rpm from variable speed driver. Safe operation range of the pump has to be limited with system parabolas, which prevents the duty point location outside of the predefined operation area. The particular study demonstrates the engineering approach for pump’s safe operation control development in MATLAB/Simulink environment, which allows to simulate the operation of the pump at different capacities in hydraulic system with variable characteristic and to predefine the conditions for efficient simultaneous pump operation in parallel connection.

  1. Advanced engineering software for in-space assembly and manned planetary spacecraft

    NASA Technical Reports Server (NTRS)

    Delaquil, Donald; Mah, Robert

    1990-01-01

    Meeting the objectives of the Lunar/Mars initiative to establish safe and cost-effective extraterrestrial bases requires an integrated software/hardware approach to operational definitions and systems implementation. This paper begins this process by taking a 'software-first' approach to systems design, for implementing specific mission scenarios in the domains of in-space assembly and operations of the manned Mars spacecraft. The technological barriers facing implementation of robust operational systems within these two domains are discussed, and preliminary software requirements and architectures that resolve these barriers are provided.

  2. A flash from the past: a case on long term follow-up of a "corridor" operation.

    PubMed

    Ricciardi, Danilo; Sarkozy, Andrea; Wauters, Kristel; Brugada, Pedro

    2013-01-01

    An electrophysiological study in a patient with a previous corridor operation was performed because of syncope. The atrial electrograms showed the persistence of the sinus rhythm in the right atrial corridor despite an organized atrial fibrillation in the left atrium. The first case described of a long term follow-up in a corridor operation, one of the first described surgical approach for the treatment of atrial fibrillation, that gave the beginning to the non-pharmacological approach of this arrhythmia. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Technical approaches for measurement of human errors

    NASA Technical Reports Server (NTRS)

    Clement, W. F.; Heffley, R. K.; Jewell, W. F.; Mcruer, D. T.

    1980-01-01

    Human error is a significant contributing factor in a very high proportion of civil transport, general aviation, and rotorcraft accidents. The technical details of a variety of proven approaches for the measurement of human errors in the context of the national airspace system are presented. Unobtrusive measurements suitable for cockpit operations and procedures in part of full mission simulation are emphasized. Procedure, system performance, and human operator centered measurements are discussed as they apply to the manual control, communication, supervisory, and monitoring tasks which are relevant to aviation operations.

  4. Low-lift-to-drag-ratio approach and landing studies using a CV-990 airplane

    NASA Technical Reports Server (NTRS)

    Kock, B. M.; Fulton, F. L.; Drinkwater, F. J., III

    1972-01-01

    The results are presented of a flight-test program utilizing a CV-990 airplane, flow in low-lift-to-drag-ratio (L/D) configurations, to simulate terminal area operation, approach, and landing of large unpowered vehicles. The results indicate that unpowered approaches and landings are practical with vehicles of the size and performance characteristics of the proposed shuttle vehicle. Low L/D landings provided touchdown dispersion patterns acceptable for operation on runways of reasonable length. The dispersion pattern was reduced when guidance was used during the final approach. High levels of pilot proficiency were not required for acceptable performance.

  5. Constrained Null Space Component Analysis for Semiblind Source Separation Problem.

    PubMed

    Hwang, Wen-Liang; Lu, Keng-Shih; Ho, Jinn

    2018-02-01

    The blind source separation (BSS) problem extracts unknown sources from observations of their unknown mixtures. A current trend in BSS is the semiblind approach, which incorporates prior information on sources or how the sources are mixed. The constrained independent component analysis (ICA) approach has been studied to impose constraints on the famous ICA framework. We introduced an alternative approach based on the null space component (NCA) framework and referred to the approach as the c-NCA approach. We also presented the c-NCA algorithm that uses signal-dependent semidefinite operators, which is a bilinear mapping, as signatures for operator design in the c-NCA approach. Theoretically, we showed that the source estimation of the c-NCA algorithm converges with a convergence rate dependent on the decay of the sequence, obtained by applying the estimated operators on corresponding sources. The c-NCA can be formulated as a deterministic constrained optimization method, and thus, it can take advantage of solvers developed in optimization society for solving the BSS problem. As examples, we demonstrated electroencephalogram interference rejection problems can be solved by the c-NCA with proximal splitting algorithms by incorporating a sparsity-enforcing separation model and considering the case when reference signals are available.

  6. Approach for Autonomous Control of Unmanned Aerial Vehicle Using Intelligent Agents for Knowledge Creation

    NASA Technical Reports Server (NTRS)

    Dufrene, Warren R., Jr.

    2004-01-01

    This paper describes the development of a planned approach for Autonomous operation of an Unmanned Aerial Vehicle (UAV). A Hybrid approach will seek to provide Knowledge Generation through the application of Artificial Intelligence (AI) and Intelligent Agents (IA) for UAV control. The applications of several different types of AI techniques for flight are explored during this research effort. The research concentration is directed to the application of different AI methods within the UAV arena. By evaluating AI and biological system approaches. which include Expert Systems, Neural Networks. Intelligent Agents, Fuzzy Logic, and Complex Adaptive Systems, a new insight may be gained into the benefits of AI and CAS techniques applied to achieving true autonomous operation of these systems. Although flight systems were explored, the benefits should apply to many Unmanned Vehicles such as: Rovers. Ocean Explorers, Robots, and autonomous operation systems. A portion of the flight system is broken down into control agents that represent the intelligent agent approach used in AI. After the completion of a successful approach, a framework for applying an intelligent agent is presented. The initial results from simulation of a security agent for communication are presented.

  7. Preservation of olfaction in surgery of olfactory groove meningiomas.

    PubMed

    Jang, Woo-Youl; Jung, Shin; Jung, Tae-Young; Moon, Kyung-Sub; Kim, In-Young

    2013-08-01

    Olfaction is commonly considered as secondary among the sensory functions, perhaps reflecting a lack of interest in sparing olfaction after surgery for the olfactory groove meningiomas (OGM). However, considering the repercussions of olfaction for the quality of life, the assessment of post-operative olfaction should be necessary. We retrospectively reviewed the olfactory outcome in patients with OGM and investigated the factors associated with sparing the post-operative olfaction. Between 1993 and 2012, 40 patients with OGM underwent surgical resection and estimated the olfactory function using the Korean version of "Sniffin'Sticks" test (KVSS). Variable factors, such as tumor size, degree of preoperative edema, tumor consistency, preoperative olfactory function, surgical approaches, patient's age, and gender were analyzed with attention to the post-operative olfactory function. Anatomical and functional preservation of olfactory structures were achieved in 26 patients (65%) and 22 patients (55%), respectively. Among the variable factors, size of tumor was significant related to the preservation of post-operative olfaction. (78.6% in size<4 cm and 42.3% in size>4 cm, p=0.035). Sparing the olfaction was significantly better in patients without preoperative olfactory dysfunction (84.6%) compared with ones with preoperative olfactory dysfunction (40.7%, p=0.016). The frontolateral approach achieved much more excellent post-operative olfactory function (71.4%) than the bifrontal approach (36.8%, p=0.032). If the tumor was smaller than 4 cm and the patients did not present olfactory dysfunction preoperatively, the possibility of sparing the post-operative olfaction was high. Among the variable surgical approaches, frontolateral route may be preferable sparing the post-operative olfaction. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. A surgical technique to expand the operative corridor for supracerebellar infratentorial approaches: technical note.

    PubMed

    Rey-Dios, Roberto; Cohen-Gadol, Aaron A

    2013-10-01

    The supracerebellar infratentorial approach is a commonly used route in neurosurgery. It provides a narrow and deep corridor to the dorsal midbrain and pineal region. The authors describe a surgical technique to expand the operative corridor and the surgeon's working angles during this approach. Thirteen cases of patients who underwent resection of their lesions using this extended approach were reviewed. During their suboccipital craniotomy, additional bone over the transverse sinus (paramedian approach) and the confluence of the sinuses (midline approach) were removed. Two sutures (tentorial stay sutures) were anchored to the tentorium anterior to the transverse sinus and tension was applied. A video narrated by the senior author describes the details of technique. This additional bone removal and tentorial stay sutures led to gentle elevation of the tentorium and partial mobilization of the dural venous sinuses superiorly. This technique enhanced operative viewing through improved illumination and expanded working angles for microsurgical instruments while minimizing the need for fixed retractors and extensive cerebellar retraction. All patients underwent satisfactory removal of their lesions. No patient suffered from any related complication. The use of stay sutures anchored on the tentorium is a simple and effective technique that expands the surgical corridor during supracerebellar infratentorial approaches.

  9. Innovative UK Approaches to Acquisition Management

    DTIC Science & Technology

    2009-05-01

    Financial and Operational Imperatives Size of UK armed forces UK Industry ? Political influence PFI / PPP Increased Scrutiny - NAO “ Commercialisation “ of the...acquisition KNOWLEDGE (EXPERIENCE – Lessons learned) KNOWLEDGE (Training) KNOWLEDGE ( Education ) OPTIMAL OPERATIONAL PERFORMANCE Operational Capability UK

  10. Creating Situational Awareness in Spacecraft Operations with the Machine Learning Approach

    NASA Astrophysics Data System (ADS)

    Li, Z.

    2016-09-01

    This paper presents a machine learning approach for the situational awareness capability in spacecraft operations. There are two types of time dependent data patterns for spacecraft datasets: the absolute time pattern (ATP) and the relative time pattern (RTP). The machine learning captures the data patterns of the satellite datasets through the data training during the normal operations, which is represented by its time dependent trend. The data monitoring compares the values of the incoming data with the predictions of machine learning algorithm, which can detect any meaningful changes to a dataset above the noise level. If the difference between the value of incoming telemetry and the machine learning prediction are larger than the threshold defined by the standard deviation of datasets, it could indicate the potential anomaly that may need special attention. The application of the machine-learning approach to the Advanced Himawari Imager (AHI) on Japanese Himawari spacecraft series is presented, which has the same configuration as the Advanced Baseline Imager (ABI) on Geostationary Environment Operational Satellite (GOES) R series. The time dependent trends generated by the data-training algorithm are in excellent agreement with the datasets. The standard deviation in the time dependent trend provides a metric for measuring the data quality, which is particularly useful in evaluating the detector quality for both AHI and ABI with multiple detectors in each channel. The machine-learning approach creates the situational awareness capability, and enables engineers to handle the huge data volume that would have been impossible with the existing approach, and it leads to significant advances to more dynamic, proactive, and autonomous spacecraft operations.

  11. An approach to the design of operations systems

    NASA Technical Reports Server (NTRS)

    Chafin, Roy L.; Curran, Patrick S.

    1993-01-01

    The MultiMission Control Team (MMCT) consists of mission controllers which provides Real-Time operations support for the Mars Observer project. The Real-Time Operations task is to insure the integrity of the ground data system, to insure that the configuration is correct to support the mission, and to monitor the spacecraft for the Spacecraft Team. Operations systems are typically developed by adapting operations systems from previous projects. Problems tend to be solved empirically when they are either anticipated or observed in testing. This development method has worked in the past when time was available for extensive Ops testing. In the present NASA budget environment, a more cost conscious design approach has become necessary. Cost is a concern because operations is an ongoing, continuous activity. Reducing costs entails reducing staff. Reducing staffing levels potentially increases the risk of mission failure. Therefore, keeping track of the risk level is necessary.

  12. Interval Neutrosophic Sets and Their Application in Multicriteria Decision Making Problems

    PubMed Central

    Zhang, Hong-yu; Wang, Jian-qiang; Chen, Xiao-hong

    2014-01-01

    As a generalization of fuzzy sets and intuitionistic fuzzy sets, neutrosophic sets have been developed to represent uncertain, imprecise, incomplete, and inconsistent information existing in the real world. And interval neutrosophic sets (INSs) have been proposed exactly to address issues with a set of numbers in the real unit interval, not just a specific number. However, there are fewer reliable operations for INSs, as well as the INS aggregation operators and decision making method. For this purpose, the operations for INSs are defined and a comparison approach is put forward based on the related research of interval valued intuitionistic fuzzy sets (IVIFSs) in this paper. On the basis of the operations and comparison approach, two interval neutrosophic number aggregation operators are developed. Then, a method for multicriteria decision making problems is explored applying the aggregation operators. In addition, an example is provided to illustrate the application of the proposed method. PMID:24695916

  13. Interval neutrosophic sets and their application in multicriteria decision making problems.

    PubMed

    Zhang, Hong-yu; Wang, Jian-qiang; Chen, Xiao-hong

    2014-01-01

    As a generalization of fuzzy sets and intuitionistic fuzzy sets, neutrosophic sets have been developed to represent uncertain, imprecise, incomplete, and inconsistent information existing in the real world. And interval neutrosophic sets (INSs) have been proposed exactly to address issues with a set of numbers in the real unit interval, not just a specific number. However, there are fewer reliable operations for INSs, as well as the INS aggregation operators and decision making method. For this purpose, the operations for INSs are defined and a comparison approach is put forward based on the related research of interval valued intuitionistic fuzzy sets (IVIFSs) in this paper. On the basis of the operations and comparison approach, two interval neutrosophic number aggregation operators are developed. Then, a method for multicriteria decision making problems is explored applying the aggregation operators. In addition, an example is provided to illustrate the application of the proposed method.

  14. 49 CFR 192.913 - When may an operator deviate its program from certain requirements of this subpart?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... management program. An operator that uses a performance-based approach that satisfies the requirements for... to demonstrate the exceptional performance of its integrity management program through the following... to the operator's pipeline system and to the operator's integrity management program; (vi) A...

  15. Flight tests of IFR landing approach systems for helicopters

    NASA Technical Reports Server (NTRS)

    Bull, J. S.; Hegarty, D. M.; Peach, L. L.; Phillips, J. D.; Anderson, D. J.; Dugan, D. C.; Ross, V. L.

    1981-01-01

    Joint NASA/FAA helicopter flight tests were conducted to investigate airborne radar approaches (ARA) and microwave landing system (MLS) approaches. Flight-test results were utilized to prove NASA with a data base to be used as a performance measure for advanced guidance and navigation concepts, and to provide FAA with data for establishment of TERPS criteria. The first flight-test investigation consisted of helicopter IFR approaches to offshore oil rigs in the Gulf of Mexico, using weather/mapping radar, operational pilots, and a Bell 212 helicopter. The second flight-test investigation consisted of IFR MLS approaches at Crows Landing (near Ames Research Center), with a Bell UH-1H helicopter, using NASA, FAA, and operational industry pilots. Tests are described and results discussed.

  16. [Conceptual foundation of the operational diagnostic approach in psychiatry].

    PubMed

    Jäger, M; Strauss, A; Frasch, K; Becker, T

    2007-08-01

    Based on the pioneering work of Emil Kraepelin, Karl Jaspers, Kurt Schneider and representatives of logical empiricism, the basic principles of the operational diagnostic approach in psychiatry are described. Operational diagnostic systems like ICD-10 and DSM-IV aimed at a standardisation of psychiatric language which can be accepted by different schools in psychiatry. However, ICD-10 and DSM-IV should not be misinterpreted as "nosology" because they do not reflect a specific model of psychiatric diseases. The advantages of operational diagnostic systems as instruments for communication in a clinical and scientific context are limited by the fact that they disregard the subjective psychopathology. This dimension, however, deserves attention in clinic and research.

  17. Don't panic--prepare: towards crisis-aware models of emergency department operations.

    PubMed

    Ceglowski, Red; Churilov, Leonid; Wasserheil, Jeff

    2005-12-01

    The existing models of Emergency Department (ED) operations that are based on the "flow-shop" management logic do not provide adequate decision support in dealing with the ED overcrowding crises. A conceptually different crisis-aware approach to ED modelling and operational decision support is introduced in this paper. It is based on Perrow's theory of "normal accidents" and calls for recognizing the inevitable nature of ED overcrowding crises within current health system setup. Managing the crisis before it happens--a standard approach in crisis management area--should become an integral part of ED operations management. The potential implications of adopting such a crisis-aware perspective for health services research and ED management are outlined.

  18. Tele-Manipulation with Two Asymmetric Slaves: Two Operators Perform Better Than One.

    PubMed

    van Oosterhout, Jeroen; Heemskerk, Cock J M; de Baar, Marco R; van der Helm, Frans C T; Abbink, David A

    2018-01-01

    Certain tele-manipulation tasks require manipulation by two asymmetric slaves, for example, a crane for hoisting and a dexterous robotic arm for fine manipulation. It is unclear how to best design human-in-the-loop control over two asymmetric slaves. The goal of this paper is to quantitatively compare the standard approach of two co-operating operators that each control a single subtask, to a single operator performing bi-manual control over the two subtasks, and a uni-manual control approach. In a human factors experiment, participants performed a heavy load maneuvering and mounting task using a vertical crane and a robotic arm. We hypothesize that bi-manual control yields worse task performance and control activity compared to co-operation, because of conflicting spatial and temporal constraints. Literature suggests that uni-manual operators should perform better than co-operation, as co-operators critically depend on each other's actions. However, other literature provides evidence that individual operators have limited capabilities in controlling asymmetric axes of two dynamic systems. The results show that the two co-operators perform the maneuvering and mounting task faster than either bi- or uni-manual operators. Compared to co-operators, uni-manual operators required more control activity for the vertical crane and less for the robotic arm. In conclusion, this study suggests that when controlling two asymmetric slaves, a co-operating pair of operators performs better than a single operator.

  19. Schools' Capacity to Absorb a "Healthy School" Approach into Their Operations: Insights from a Realist Evaluation

    ERIC Educational Resources Information Center

    Deschesnes, Marthe; Drouin, Nathalie; Tessier, Caroline; Couturier, Yves

    2014-01-01

    Purpose: The purpose of this paper is to understand how a Canadian intervention based on a professional development (PD) model did or did not influence schools' capacities to absorb a Healthy School (HS) approach into their operations. This study is the second part of a research project: previously published results regarding this research…

  20. Flight Test Comparison of Synthetic Vision Display Concepts at Dallas/Fort Worth International Airport

    NASA Technical Reports Server (NTRS)

    Glaab, Louis J.; Kramer, Lynda J.; Arthur, Trey; Parrish, Russell V.; Barry, John S.

    2003-01-01

    Limited visibility is the single most critical factor affecting the safety and capacity of worldwide aviation operations. Synthetic Vision Systems (SVS) technology can solve this visibility problem with a visibility solution. These displays employ computer-generated terrain imagery to present 3D, perspective out-the-window scenes with sufficient information and realism to enable operations equivalent to those of a bright, clear day, regardless of weather conditions. To introduce SVS display technology into as many existing aircraft as possible, a retrofit approach was defined that employs existing HDD display capabilities for glass cockpits and HUD capabilities for the other aircraft. This retrofit approach was evaluated for typical nighttime airline operations at a major international airport. Overall, 6 evaluation pilots performed 75 research approaches, accumulating 18 hours flight time evaluating SVS display concepts that used the NASA LaRC's Boeing B-757-200 aircraft at Dallas/Fort Worth International Airport. Results from this flight test establish the SVS retrofit concept, regardless of display size, as viable for tested conditions. Future assessments need to extend evaluation of the approach to operations in an appropriate, terrain-challenged environment with daytime test conditions.

  1. Modeling and Control for Microgrids

    NASA Astrophysics Data System (ADS)

    Steenis, Joel

    Traditional approaches to modeling microgrids include the behavior of each inverter operating in a particular network configuration and at a particular operating point. Such models quickly become computationally intensive for large systems. Similarly, traditional approaches to control do not use advanced methodologies and suffer from poor performance and limited operating range. In this document a linear model is derived for an inverter connected to the Thevenin equivalent of a microgrid. This model is then compared to a nonlinear simulation model and analyzed using the open and closed loop systems in both the time and frequency domains. The modeling error is quantified with emphasis on its use for controller design purposes. Control design examples are given using a Glover McFarlane controller, gain scheduled Glover McFarlane controller, and bumpless transfer controller which are compared to the standard droop control approach. These examples serve as a guide to illustrate the use of multi-variable modeling techniques in the context of robust controller design and show that gain scheduled MIMO control techniques can extend the operating range of a microgrid. A hardware implementation is used to compare constant gain droop controllers with Glover McFarlane controllers and shows a clear advantage of the Glover McFarlane approach.

  2. Foresight for commanders: a methodology to assist planning for effects-based operations

    NASA Astrophysics Data System (ADS)

    Davis, Paul K.; Kahan, James P.

    2006-05-01

    Looking at the battlespace as a system of systems is a cornerstone of Effects-Based Operations and a key element in the planning of such operations, and in developing the Commander's Predictive Environment. Instead of a physical battleground to be approached with weapons of force, the battlespace is an interrelated super-system of political, military, economic, social, information and infrastructure systems to be approached with diplomatic, informational, military and economic actions. A concept that has proved useful in policy arenas other than defense, such as research and development for information technology, addressing cybercrime, and providing appropriate and cost-effective health care, is foresight. In this paper, we provide an overview of how the foresight approach addresses the inherent uncertainties in planning courses of action, present a set of steps in the conduct of foresight, and then illustrate the application of foresight to a commander's decision problem. We conclude that foresight approach that we describe is consistent with current doctrinal intelligence preparation of the battlespace and operational planning, but represents an advance in that it explicitly addresses the uncertainties in the environment and planning in a way that identifies strategies that are robust over different possible ground truths. It should supplement other planning methods.

  3. Approach to Operational Experimental Estimation of Static Stresses of Elements of Mechanical Structures

    NASA Astrophysics Data System (ADS)

    Sedov, A. V.; Kalinchuk, V. V.; Bocharova, O. V.

    2018-01-01

    The evaluation of static stresses and strength of units and components is a crucial task for increasing reliability in the operation of vehicles and equipment, to prevent emergencies, especially in structures made of metal and composite materials. At the stage of creation and commissioning of structures to control the quality of manufacturing of individual elements and components, diagnostic control methods are widely used. They are acoustic, ultrasonic, X-ray, radiation methods and others. The using of these methods to control the residual life and the degree of static stresses of units and parts during operation is fraught with great difficulties both in methodology and in instrumentation. In this paper, the authors propose an effective approach of operative control of the degree of static stresses of units and parts of mechanical structures which are in working condition, based on recording the changing in the surface wave properties of a system consisting of a sensor and a controlled environment (unit, part). The proposed approach of low-frequency diagnostics of static stresses presupposes a new adaptive-spectral analysis of a surface wave created by external action (impact). It is possible to estimate implicit stresses of structures in the experiment due to this approach.

  4. Second-order relativistic corrections for the S(L=0) states in one- and two-electron atomic systems

    NASA Astrophysics Data System (ADS)

    Frolov, A. M.; Mitelut, C. C.; Zhong, Z.

    2005-01-01

    An analytical approach is developed to compute the first- (similar to alpha(2)) and second-order (similar to alpha(4)) relativistic corrections in one- and two-electron atomic systems. The approach is based on the reduction of all operators to divergent (singular) and nondivergent (regular) parts. Then, we show that all the divergent parts from the differentmatrix elements cancel each other. The remaining expression contains only regular operators and its expectation value can be easily computed. Analysis of the S(L = 0) states in such systems is of specific interest since the corresponding operators for these states contain a large number of singularities. For one-electron systems the computed relativistic corrections coincide exactly with the appropriate result that follows from the Taylor expansion of the relativistic (i.e., Dirac) energy. We also discuss an alternative approach that allows one to cancel all singularities by using the so-called operator-compensation technique. This second approach is found to be very effective in applications of more complex systems, such as helium-like atoms and ions, H-2(+)-like ions, and some exotic three-body systems.

  5. Flight Test Evaluation of the Airborne Information for Lateral Spacing (AILS) Concept

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.

    2002-01-01

    The Airborne Information for Lateral Spacing (AILS) concept is designed to support independent parallel approach operations to runways spaced as close as 2,500 feet. This report briefly describes the AILS operational concept and the results of a flight test of one implementation of this concept. The focus of this flight test experiment was to validate a prior simulator study, evaluating pilot performance, pilot acceptability, and minimum miss-distances for the rare situation in which an aircraft on one approach intrudes into the path of an aircraft on the other approach. Although the flight data set was not meant to be a statistically valid sample, the trends acquired in flight followed those of the simulator and therefore met the intent of validating the findings from the simulator. Results from this study showed that the design-goal mean miss-distance of 1,200 feet to potential collision situations was surpassed with an actual mean miss-distance of 1,859 feet. Pilot reaction times to the alerting system, which was an operational concern, averaged 0.65 seconds, were well below the design goal reaction time of 2.0 seconds. From the results of both of these tests, it can be concluded that this operational concept, with supporting technology and procedures, may provide an operationally viable means for conducting simultaneous, independent instrument approaches to runways spaced as close as 2500 ft.

  6. Combined operative technique with anterior surgical approach and video-assisted thoracoscopic surgical lobectomy for anterior superior sulcus tumours.

    PubMed

    Yokoyama, Yuhei; Chen, Fengshi; Aoyama, Akihiro; Sato, Toshihiko; Date, Hiroshi

    2014-11-01

    Video-assisted thoracoscopic surgery (VATS) has been widely used, but surgical resections of superior sulcus tumours remain challenging because of their anatomical location. For such cases, less-invasive procedures, such as the anterior transcervical-thoracic and transmanubrial approaches, have been widely performed because of their excellent visualization of the subclavian vessels. Recently, a combined operative technique with an anterior surgical approach and VATS for anterior superior sulcus tumours has been introduced. Herein, we report three cases of anterior superior sulcus tumours successfully resected by surgical approaches combined with a VATS-based lobectomy. In all cases, operability was confirmed by VATS, and upper lobectomies with hilar and mediastinal lymph node dissections were performed. Subsequently, dissections of the anterior inlet of the tumours were performed using the transmanubrial approach in two patients and the anterior trans-cervical-thoracic approach in one patient. Both approaches provided excellent access to the anterior inlet of the tumour and exposure of the subclavian vessels, resulting in radical resection of the tumour with concomitant resection of the surrounding anatomical structures, including the chest wall and vessels. In conclusion, VATS lobectomy combined with the anterior surgical approach might be an excellent procedure for the resection of anterior superior sulcus tumours. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  7. One tool - one team: the marriage of test and operations in a low-budget spacecraft development

    NASA Astrophysics Data System (ADS)

    Finley, Charles J.

    2006-05-01

    The Air Force Research Laboratory's Space Vehicles Directorate (AFRL/VS) and the Department of Defense Space Test Program (STP) are two organizations that have partnered on more than 85 missions since 1968 to develop, launch, and operate Research and Development, Test and Evaluation space missions. As valuable as these missions have been to the follow-on generation of Operational systems, they are consistently under-funded and forced to execute on excessively ambitious development schedules. Due to these constraints, space mission development teams that serve the RDT&E community are faced with a number of unique technical and programmatic challenges. AFRL and STP have taken various approaches throughout the mission lifecycle to accelerate their development schedules, without sacrificing cost or system reliability. In the areas of test and operations, they currently employ one of two strategies. Historically, they have sought to avoid the added cost and complexity associated with coupled development schedules and segregated the spacecraft development and test effort from the ground operations system development and test effort. However, because these efforts have far more in common than they have differences, they have more recently attempted to pursue parallel I&T and Operations development and readiness efforts. This paper seeks to compare and contrast the "decoupled test and operations" approach, used by such missions as C/NOFS and Coriolis, with the "coupled test and operations" approach, adopted by the XSS-11 and TacSat-2 missions.

  8. The Building Blocks for JWST I and T (Integrations and Test) to Operations - From Simulator to Flight Units

    NASA Technical Reports Server (NTRS)

    Fatig, Curtis; Ochs, William; Johns, Alan; Seaton, Bonita; Adams, Cynthia; Wasiak, Francis; Jones, Ronald; Jackson, Wallace

    2012-01-01

    The James Webb Space Telescope (JWST) Project has an extended integration and test (I&T) phase due to long procurement and development times of various components as well as recent launch delays. The JWST Ground Segment and Operations group has developed a roadmap of the various ground and flight elements and their use in the various JWST I&T test programs. The JWST Project s building block approach to the eventual operational systems, while not new, is complex and challenging; a large-scale mission like JWST involves international partners, many vendors across the United States, and competing needs for the same systems. One of the challenges is resource balancing so simulators and flight products for various elements congeal into integrated systems used for I&T and flight operations activities. This building block approach to an incremental buildup provides for early problem identification with simulators and exercises the flight operations systems, products, and interfaces during the JWST I&T test programs. The JWST Project has completed some early I&T with the simulators, engineering models and some components of the operational ground system. The JWST Project is testing the various flight units as they are delivered and will continue to do so for the entire flight and operational system. The JWST Project has already and will continue to reap the value of the building block approach on the road to launch and flight operations.

  9. Outcomes of laparoscopic resection of Meckel's diverticulum are equivalent to open laparotomy.

    PubMed

    Ezekian, Brian; Leraas, Harold J; Englum, Brian R; Gilmore, Brian F; Reed, Christopher; Fitzgerald, Tamara N; Rice, Henry E; Tracy, Elisabeth T

    2018-03-15

    Meckel's diverticulum (MD) is a common congenital anomaly caused by failure of involution of the omphalomesenteric duct. Enthusiasm for minimally invasive surgery (MIS) in children has burgeoned as technologies have advanced, but the outcomes of laparoscopic resection in comparison to open laparotomy for MD remain poorly defined. We queried a large national database to compare current practice patterns and clinical outcomes between surgical approaches for MD in the pediatric population. The National Surgical Quality Improvement Program-Pediatric (NSQIP-Ped) database was queried for patients undergoing surgical intervention for MD (2011-2014). Patients were stratified by surgical approach. Baseline characteristics, intraoperative variables, and perioperative complications were compared by univariate analysis using Pearson's χ 2 test for categorical variables and Kruskall-Wallis test for continuous variables. Primary outcomes of interest were length of stay (LOS), rate of readmission, and 30-day mortality. Secondary outcomes included operative time, anesthesia time, postoperative complications, and rates of reoperation. A total of 148 cases of MD were identified, of which 73 (49.3%) were initially managed with a laparoscopic approach and 75 (50.7%) were managed with an open approach. We found a high rate of conversion from laparoscopy to an open approach (20/73 or 27.4%). The median age of the laparoscopic group was higher than the open group (8.3 vs. 2.5years, p<0.001). Operative and anesthesia time, LOS, 30-day mortality, post-operative complications, and rates of reoperation and readmission were similar between groups (all p>0.05). Nearly half of all resections for MD in children are now approached laparoscopically. This approach has equivalent outcomes to traditional open laparotomy. More widespread use of a hybrid approach with laparoscopy and exteriorization of the small bowel through an extended port site may facilitate avoiding open laparotomy. Routine conversion to open for palpation of the MD or segmental small bowel resection should be avoided in the absence of compelling intra-operative findings or operative complications. Level III (retrospective comparative study). Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Spacecraft rendezvous operational considerations affecting vehicle systems design and configuration

    NASA Astrophysics Data System (ADS)

    Prust, Ellen E.

    One lesson learned from Orbiting Maneuvering Vehicle (OMV) program experience is that Design Reference Missions must include an appropriate balance of operations and performance inputs to effectively drive vehicle systems design and configuration. Rendezvous trajectory design is based on vehicle characteristics (e.g., mass, propellant tank size, and mission duration capability) and operational requirements, which have evolved through the Gemini, Apollo, and STS programs. Operational constraints affecting the rendezvous final approach are summarized. The two major objectives of operational rendezvous design are vehicle/crew safety and mission success. Operational requirements on the final approach which support these objectives include: tracking/targeting/communications; trajectory dispersion and navigation uncertainty handling; contingency protection; favorable sunlight conditions; acceptable relative state for proximity operations handover; and compliance with target vehicle constraints. A discussion of the ways each of these requirements may constrain the rendezvous trajectory follows. Although the constraints discussed apply to all rendezvous, the trajectory presented in 'Cargo Transfer Vehicle Preliminary Reference Definition' (MSFC, May 1991) was used as the basis for the comments below.

  11. An operational approach to high resolution agro-ecological zoning in West-Africa.

    PubMed

    Le Page, Y; Vasconcelos, Maria; Palminha, A; Melo, I Q; Pereira, J M C

    2017-01-01

    The objective of this work is to develop a simple methodology for high resolution crop suitability analysis under current and future climate, easily applicable and useful in Least Developed Countries. The approach addresses both regional planning in the context of climate change projections and pre-emptive short-term rural extension interventions based on same-year agricultural season forecasts, while implemented with off-the-shelf resources. The developed tools are applied operationally in a case-study developed in three regions of Guinea-Bissau and the obtained results, as well as the advantages and limitations of methods applied, are discussed. In this paper we show how a simple approach can easily generate information on climate vulnerability and how it can be operationally used in rural extension services.

  12. A mesh-free approach to acoustic scattering from multiple spheres nested inside a large sphere by using diagonal translation operators.

    PubMed

    Hesford, Andrew J; Astheimer, Jeffrey P; Greengard, Leslie F; Waag, Robert C

    2010-02-01

    A multiple-scattering approach is presented to compute the solution of the Helmholtz equation when a number of spherical scatterers are nested in the interior of an acoustically large enclosing sphere. The solution is represented in terms of partial-wave expansions, and a linear system of equations is derived to enforce continuity of pressure and normal particle velocity across all material interfaces. This approach yields high-order accuracy and avoids some of the difficulties encountered when using integral equations that apply to surfaces of arbitrary shape. Calculations are accelerated by using diagonal translation operators to compute the interactions between spheres when the operators are numerically stable. Numerical results are presented to demonstrate the accuracy and efficiency of the method.

  13. A functional approach for research on cognitive control: Analysing cognitive control tasks and their effects in terms of operant conditioning.

    PubMed

    Liefooghe, Baptist; De Houwer, Jan

    2016-02-01

    Cognitive control is an important mental ability that is examined using a multitude of cognitive control tasks and effects. The present paper presents the first steps in the elaboration of a functional approach, which aims to uncover the communalities and differences between different cognitive control tasks and their effects. Based on the idea that responses in cognitive control tasks qualify as operant behaviour, we propose to reinterpret cognitive control tasks in terms of operant contingencies and cognitive control effects as instances of moderated stimulus control. We illustrate how our approach can be used to uncover communalities between topographically different cognitive control tasks and can lead to novel questions about the processes underlying cognitive control. © 2015 International Union of Psychological Science.

  14. A mesh-free approach to acoustic scattering from multiple spheres nested inside a large sphere by using diagonal translation operators

    PubMed Central

    Hesford, Andrew J.; Astheimer, Jeffrey P.; Greengard, Leslie F.; Waag, Robert C.

    2010-01-01

    A multiple-scattering approach is presented to compute the solution of the Helmholtz equation when a number of spherical scatterers are nested in the interior of an acoustically large enclosing sphere. The solution is represented in terms of partial-wave expansions, and a linear system of equations is derived to enforce continuity of pressure and normal particle velocity across all material interfaces. This approach yields high-order accuracy and avoids some of the difficulties encountered when using integral equations that apply to surfaces of arbitrary shape. Calculations are accelerated by using diagonal translation operators to compute the interactions between spheres when the operators are numerically stable. Numerical results are presented to demonstrate the accuracy and efficiency of the method. PMID:20136208

  15. Experimental studies of systematic multiple-energy operation at HIMAC synchrotron

    NASA Astrophysics Data System (ADS)

    Mizushima, K.; Katagiri, K.; Iwata, Y.; Furukawa, T.; Fujimoto, T.; Sato, S.; Hara, Y.; Shirai, T.; Noda, K.

    2014-07-01

    Multiple-energy synchrotron operation providing carbon-ion beams with various energies has been used for scanned particle therapy at NIRS. An energy range from 430 to 56 MeV/u and about 200 steps within this range are required to vary the Bragg peak position for effective treatment. The treatment also demands the slow extraction of beam with highly reliable properties, such as spill, position and size, for all energies. We propose an approach to generating multiple-energy operation meeting these requirements within a short time. In this approach, the device settings at most energy steps are determined without manual adjustments by using systematic parameter tuning depending on the beam energy. Experimental verification was carried out at the HIMAC synchrotron, and its results proved that this approach can greatly reduce the adjustment period.

  16. Speed Control Law for Precision Terminal Area In-Trail Self Spacing

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.

    2002-01-01

    This document describes a speed control law for precision in-trail airborne self-spacing during final approach. This control law was designed to provide an operationally viable means to obtain a desired runway threshold crossing time or minimum distance, one aircraft relative to another. The control law compensates for dissimilar final approach speeds between aircraft pairs and provides guidance for a stable final approach. This algorithm has been extensively tested in Monte Carlo simulation and has been evaluated in piloted simulation, with preliminary results indicating acceptability from operational and workload standpoints.

  17. Requirements Definition for Force Level Command and Control in the Tactical Air Control System: An Evolutionary Approach Toward Meeting Near Term and Future Operational Needs.

    DTIC Science & Technology

    1985-01-01

    numerous major exercises, such as WINTEX- CIMEX , REFORGER, CRESTED EAGLE, and BRIGHT STAR. USAFE is now actively planning an evolutionary approach toward C2...during WINTEX- CIMEX 85, we have been investigating a number of approaches to enhancing joint air-ground operations and providing a means for better...throughout the ground battle elements. The USAREUR Distributed Decision Aid System (UD[1AS) was initially deployed in Exercise WINTEX- CIMEX 84. During

  18. A hybrid protection approaches for denial of service (DoS) attacks in wireless sensor networks

    NASA Astrophysics Data System (ADS)

    Gunasekaran, Mahalakshmi; Periakaruppan, Subathra

    2017-06-01

    Wireless sensor network (WSN) contains the distributed autonomous devices with the sensing capability of physical and environmental conditions. During the clustering operation, the consumption of more energy causes the draining in battery power that leads to minimum network lifetime. Hence, the WSN devices are initially operated on low-power sleep mode to maximise the lifetime. But, the attacks arrival cause the disruption in low-power operating called denial of service (DoS) attacks. The conventional intrusion detection (ID) approaches such as rule-based and anomaly-based methods effectively detect the DoS attacks. But, the energy consumption and false detection rate are more. The absence of attack information and broadcast of its impact to the other cluster head (CH) leads to easy DoS attacks arrival. This article combines the isolation and routing tables to detect the attack in the specific cluster and broadcasts the information to other CH. The intercommunication between the CHs prevents the DoS attacks effectively. In addition, the swarm-based defence approach is proposed to migrate the fault channel to normal operating channel through frequency hop approaches. The comparative analysis between the proposed table-based intrusion detection systems (IDSs) and swarm-based defence approaches with the traditional IDS regarding the parameters of transmission overhead/efficiency, energy consumption, and false positive/negative rates proves the capability of DoS prediction/prevention in WSN.

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

    Jager, Yetta; Smith, Brennan T

    Hydroelectric power provides a cheap source of electricity with few carbon emissions. Yet, reservoirs are not operated sustainably, which we define as meeting societal needs for water and power while protecting long-term health of the river ecosystem. Reservoirs that generate hydropower are typically operated with the goal of maximizing energy revenue, while meeting other legal water requirements. Reservoir optimization schemes used in practice do not seek flow regimes that maximize aquatic ecosystem health. Here, we review optimization studies that considered environmental goals in one of three approaches. The first approach seeks flow regimes that maximize hydropower generations while satisfying legalmore » requirements, including environmental (or minimum) flows. Solutions from this approach are often used in practice to operate hydropower projects. In the second approach, flow releases from a dam are timed to meet water quality constraints on dissolved oxygen (DO), temperature and nutrients. In the third approach, flow releases are timed to improve the health of fish populations. We conclude by suggesting three steps for bringing multi-objective reservoir operation closer to the goal of ecological sustainability: (1) conduct research to identify which features of flow variation are essential for river health and to quantify these relationships, (2) develop valuation methods to assess the total value of river health and (3) develop optimal control softwares that combine water balance modeling with models that predict ecosystem responses to flow.« less

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

    Jager, Yetta; Smith, Brennan T

    Hydroelectric power provides a cheap source of electricity with few carbon emissions. Yet, reservoirs are not operated sustainably, which we define as meeting societal needs for water and power while protecting long-term health of the river ecosystem. Reservoirs that generate hydropower are typically operated with the goal of maximizing energy revenue, while meeting other legal water requirements. Reservoir optimization schemes used in practice do not seek flow regimes that maximize aquatic ecosystem health. Here, we review optimization studies that considered environmental goals in one of three approaches. The first approach seeks flow regimes that maximize hydropower generation, while satisfying legalmore » requirements, including environmental (or minimum) flows. Solutions from this approach are often used in practice to operate hydropower projects. In the second approach, flow releases from a dam are timed to meet water quality constraints on dissolved oxygen (DO), temperature and nutrients. In the third approach, flow releases are timed to improve the health of fish populations. We conclude by suggesting three steps for bringing multi-objective reservoir operation closer to the goal of ecological sustainability: (1) conduct research to identify which features of flow variation are essential for river health and to quantify these relationships, (2) develop valuation methods to assess the total value of river health and (3) develop optimal control softwares that combine water balance modelling with models that predict ecosystem responses to flow.« less

  1. Comparison of outcome measures and complication rates following three different approaches for primary total hip arthroplasty: a pragmatic randomised controlled trial.

    PubMed

    Talia, Adrian J; Coetzee, Cassandra; Tirosh, Oren; Tran, Phong

    2018-01-08

    Total hip arthroplasty is one of the most commonly performed surgical procedures worldwide. There are a number of surgical approaches for total hip arthroplasty and no high-level evidence supporting one approach over the other. Each approach has its unique benefits and drawbacks. This trial aims to directly compare the three most common surgical approaches for total hip arthroplasty. This is a single-centre study conducted at Western Health, Melbourne, Australia; a large metropolitan centre. It is a pragmatic, parallel three-arm, randomised controlled trial. Sample size will be 243 participants (81 in each group). Randomisation will be secure, web-based and managed by an independent statistician. Patients and research team will be blinded pre-operatively, but not post-operatively. Intervention will be either direct anterior, lateral or posterior approach for total hip arthroplasty, and the three arms will be directly compared. Participants will be aged over 18 years, able to provide informed consent and recruited from our outpatients. Patients who are having revision surgery or have indications for hip replacement other than osteoarthritis (i.e., fracture, malignancy, development dysplasia) will be excluded from the trial. The Oxford Hip Score will be determined for patients pre-operatively and 6 weeks, 6, 12 and 24 months post-operatively. The Oxford Hip Score at 24 months will be the primary outcome measure. Secondary outcome measures will be dislocation, infection, intraoperative and peri-prosthetic fracture rate, length of hospital stay and pain level, reported using a visual analogue scale. Many studies have evaluated approaches for total hip arthroplasty and arthroplasty registries worldwide are now collecting this data. However no study to date has compared these three common approaches directly in a randomised fashion. No trial has used patient-reported outcome measures to evaluate success. This pragmatic study aims to identify differences in patient perception of total hip arthroplasty depending on surgical approach. Australian New Zealand Clinical Trials Registry, ACTRN12617000272392 . Registered on 22 February 2017.

  2. Simulator Evaluation of Airborne Information for Lateral Spacing (AILS) Concept

    NASA Technical Reports Server (NTRS)

    Abbott, Terence S.; Elliott, Dawn M.

    2001-01-01

    The Airborne Information for Lateral Spacing (AILS) concept is designed to support independent parallel approach operations to runways spaced as close as 2500 ft. This report describes the AILS operational concept and the results of a ground-based flight simulation experiment of one implementation of this concept. The focus of this simulation experiment was to evaluate pilot performance, pilot acceptability, and minimum miss-distances for the rare situation in which all aircraft oil one approach intrudes into the path of an aircraft oil the other approach. Results from this study showed that the design-goal mean miss-distance of 1200 ft to potential collision situations was surpassed with an actual mean miss-distance of 2236 ft. Pilot reaction times to the alerting system, which was an operational concern, averaged 1.11 sec, well below the design-goal reaction time 2.0 sec.These quantitative results and pilot subjective data showed that the AILS concept is reasonable from an operational standpoint.

  3. Novel, Web-based, information-exploration approach for improving operating room logistics and system processes.

    PubMed

    Nagy, Paul G; Konewko, Ramon; Warnock, Max; Bernstein, Wendy; Seagull, Jacob; Xiao, Yan; George, Ivan; Park, Adrian

    2008-03-01

    Routine clinical information systems now have the ability to gather large amounts of data that surgical managers can access to create a seamless and proactive approach to streamlining operations and minimizing delays. The challenge lies in aggregating and displaying these data in an easily accessible format that provides useful, timely information on current operations. A Web-based, graphical dashboard is described in this study, which can be used to interpret clinical operational data, allow managers to see trends in data, and help identify inefficiencies that were not apparent with more traditional, paper-based approaches. The dashboard provides a visual decision support tool that assists managers in pinpointing areas for continuous quality improvement. The limitations of paper-based techniques, the development of the automated display system, and key performance indicators in analyzing aggregate delays, time, specialties, and teamwork are reviewed. Strengths, weaknesses, opportunities, and threats associated with implementing such a program in the perioperative environment are summarized.

  4. Robotic-assisted cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC).

    PubMed

    Gabriel, Emmanuel; Elli, Enrique; Bagaria, Sanjay; Wasif, Nabil; Grotz, Travis; Stauffer, John; Kasi, Pashtoon M; Asbun, Horacio

    2018-05-05

    Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is an appropriate treatment for select patients with peritoneal carcinomatosis. While most commonly performed through an open incision, the laparoscopic approach has been reported and offers short-term benefits. A robotic-assisted approach for carcinomatosis of gastrointestinal origin, however, has not yet been described. We report our approach to robotic-assisted CRS-HIPEC for a patient with a perforated appendiceal mucocele. Our dynamic video highlights the advantages of this approach. Our patient was a 57-year-old woman with minimal residual disseminated peritoneal adenomucinosis (DPAM), having a peritoneal carcinomatosis index (PCI) score of 1. She had a previous surgical history of a Roux-en-Y gastric bypass. A robotic-assisted approach was utilized using the Intuitive daVinci Xi robotic surgical system through 4 ports. No laparoscopic assistant port was required. The operative time was 426 min, and the estimated blood loss was 50 cc. The greater omentum, falciform ligament, bilateral ovaries, and two small areas of tumor implant were resected. The post-operative length of stay was 4 days, and the patient had regained bowel function by post-operative day 2. Our video demonstrates the feasibility of a robotic-assisted CRS-HIPEC in a patient with minimal, residual DPAM. Similar to a laparoscopic approach, the short-term outcomes are improved as compared to an open approach. An MIS approach to CRS-HIPEC, now with the first-reported robotic-assisted approach, is a viable option for select patients with peritoneal tumors.

  5. Applying Behavior-Based Robotics Concepts to Telerobotic Use of Power Tooling

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

    Noakes, Mark W; Hamel, Dr. William R.

    While it has long been recognized that telerobotics has potential advantages to reduce operator fatigue, to permit lower skilled operators to function as if they had higher skill levels, and to protect tools and manipulators from excessive forces during operation, relatively little laboratory research in telerobotics has actually been implemented in fielded systems. Much of this has to do with the complexity of the implementation and its lack of ability to operate in complex unstructured remote systems environments. One possible solution is to approach the tooling task using an adaptation of behavior-based techniques to facilitate task decomposition to a simplermore » perspective and to provide sensor registration to the task target object in the field. An approach derived from behavior-based concepts has been implemented to provide automated tool operation for a teleoperated manipulator system. The generic approach is adaptable to a wide range of typical remote tools used in hot-cell and decontamination and dismantlement-type operations. Two tasks are used in this work to test the validity of the concept. First, a reciprocating saw is used to cut a pipe. The second task is bolt removal from mockup process equipment. This paper explains the technique, its implementation, and covers experimental data, analysis of results, and suggestions for implementation on fielded systems.« less

  6. Interest point detection for hyperspectral imagery

    NASA Astrophysics Data System (ADS)

    Dorado-Muñoz, Leidy P.; Vélez-Reyes, Miguel; Roysam, Badrinath; Mukherjee, Amit

    2009-05-01

    This paper presents an algorithm for automated extraction of interest points (IPs)in multispectral and hyperspectral images. Interest points are features of the image that capture information from its neighbours and they are distinctive and stable under transformations such as translation and rotation. Interest-point operators for monochromatic images were proposed more than a decade ago and have since been studied extensively. IPs have been applied to diverse problems in computer vision, including image matching, recognition, registration, 3D reconstruction, change detection, and content-based image retrieval. Interest points are helpful in data reduction, and reduce the computational burden of various algorithms (like registration, object detection, 3D reconstruction etc) by replacing an exhaustive search over the entire image domain by a probe into a concise set of highly informative points. An interest operator seeks out points in an image that are structurally distinct, invariant to imaging conditions, stable under geometric transformation, and interpretable which are good candidates for interest points. Our approach extends ideas from Lowe's keypoint operator that uses local extrema of Difference of Gaussian (DoG) operator at multiple scales to detect interest point in gray level images. The proposed approach extends Lowe's method by direct conversion of scalar operations such as scale-space generation, and extreme point detection into operations that take the vector nature of the image into consideration. Experimental results with RGB and hyperspectral images which demonstrate the potential of the method for this application and the potential improvements of a fully vectorial approach over band-by-band approaches described in the literature.

  7. Induced simplified neutrosophic correlated aggregation operators for multi-criteria group decision-making

    NASA Astrophysics Data System (ADS)

    Şahin, Rıdvan; Zhang, Hong-yu

    2018-03-01

    Induced Choquet integral is a powerful tool to deal with imprecise or uncertain nature. This study proposes a combination process of the induced Choquet integral and neutrosophic information. We first give the operational properties of simplified neutrosophic numbers (SNNs). Then, we develop some new information aggregation operators, including an induced simplified neutrosophic correlated averaging (I-SNCA) operator and an induced simplified neutrosophic correlated geometric (I-SNCG) operator. These operators not only consider the importance of elements or their ordered positions, but also take into account the interactions phenomena among decision criteria or their ordered positions under multiple decision-makers. Moreover, we present a detailed analysis of I-SNCA and I-SNCG operators, including the properties of idempotency, commutativity and monotonicity, and study the relationships among the proposed operators and existing simplified neutrosophic aggregation operators. In order to handle the multi-criteria group decision-making (MCGDM) situations where the weights of criteria and decision-makers usually correlative and the criterion values are considered as SNNs, an approach is established based on I-SNCA operator. Finally, a numerical example is presented to demonstrate the proposed approach and to verify its effectiveness and practicality.

  8. A Comparison of Two Different Approaches to Hydrazine Loading of Spacecraft: The Use of SCAPE and Alternative Approaches

    NASA Technical Reports Server (NTRS)

    Houseman, John; Patzold, Jack D.; Jackson, Julie R.; Brown, Pamela R.

    1999-01-01

    The loading of spacecraft with Hydrazine type fuels has long been recognized as a hazardous operation. This has led to safety strategies that include the use of SCAPE protective suits for personnel. The use of SCAPE suits have an excellent safety record, however there are associated drawbacks. Drawbacks include the high cost of maintaining and cleaning the suits, reduced mobility and dexterity when wearing the suits, the requirement for extensive specialized health and safety training, and the need to rotate personnel every two hours. A study was undertaken to look at procedures and/or equipment to eliminate or reduce the time spent in SCAPE-type operations. The major conclusions are drawn from observations of the loading of the JPL/NASA spacecraft Deep Space One (DS1) at KSC and the loading of a commercial communications satellite by Motorola at Vandenberg AF Base. The DS1 operations require extensive use of SCAPE suits, while the Motorola operation uses only SPLASH attire with a two-man team on standby in SCAPE. The Motorola team used very different loading equipment and procedures based on an integrated approach involving the propellant supplier. Overall, the Motorola approach was very clean, much faster and simpler than the DS1 procedure. The DS1 spacecraft used a bladder in the propellant tank, whereas the Motorola spacecraft used a Propellant Management Device (PMD). The Motorola approach cannot be used for tanks with bladders. To overcome this problem, some new procedures and new equipment are proposed to enable tanks with bladders to be loaded without using SCAPE, using a modified Motorola approach. Overall, it appears feasible to adopt the non-SCAPE approach while maintaining a very high degree of safety and reliability.

  9. Olfactory groove meningiomas from neurosurgical and ear, nose, and throat perspectives: approaches, techniques, and outcomes.

    PubMed

    Spektor, Sergey; Valarezo, Javier; Fliss, Dan M; Gil, Ziv; Cohen, Jose; Goldman, Jose; Umansky, Felix

    2005-10-01

    To review the surgical approaches, techniques, outcomes, and recurrence rates in a series of 80 olfactory groove meningioma (OGM) patients operated on between 1990 and 2003. Eighty patients underwent 81 OGM surgeries. Tumor diameter varied from 2 to 9 cm (average, 4.6 cm). In 35 surgeries (43.2%), the tumor was removed through bifrontal craniotomy; nine operations (11.1%) were performed through a unilateral subfrontal approach; 18 surgeries (22.2%) were performed through a pterional approach; seven surgeries (8.6%) were carried out using a fronto-orbital craniotomy; and 12 procedures (14.8%) were accomplished via a subcranial approach. Nine patients (11.3%) had undergone surgery previously and had recurrent tumor. Total removal was obtained in 72 patients (90.0%); subtotal removal was achieved in 8 patients (10.0%). Two patients, one with total and one with subtotal removal, had atypical (World Health Organization Grade II) meningiomas, whereas 78 patients had World Health Organization Grade I tumors. There was no operative mortality and no new permanent focal neurological deficit besides anosmia. Twenty-five patients (31.3%) experienced surgery-related complications. There were no recurrences in 75 patients (93.8%) 6 to 164 months (mean, 70.8 mo) after surgery. Three patients (3.8%) were lost to follow-up. In two patients (2.5%) with subtotal removal, the residual evidenced growth on computed tomography and/or magnetic resonance imaging 1 year after surgery. One of them had an atypical meningioma. The second, a multiple meningiomata patient, was operated on twice in this series. A variety of surgical approaches are used for OGM resection. An approach tailored to the tumor's size, location, and extension, combined with modern microsurgical cranial base techniques, allows full OGM removal with minimal permanent morbidity, excellent neurological outcome, and very low recurrence rates.

  10. Factors affecting the surgical approach and timing of bilateral adrenalectomy.

    PubMed

    Lan, Billy Y; Taskin, Halit E; Aksoy, Erol; Birsen, Onur; Dural, Cem; Mitchell, Jamie; Siperstein, Allan; Berber, Eren

    2015-07-01

    Laparoscopic adrenalectomy has gained widespread acceptance. However, the optimal surgical approach to laparoscopic bilateral adrenalectomy has not been clearly defined. The aim of this study is to analyze the patient and intraoperative factors affecting the feasibility and outcome of different surgical approaches to define an algorithm for bilateral adrenalectomy. Between 2000 and 2013, all patients who underwent bilateral adrenalectomy at a single institution were selected for retrospective analysis. Patient factors, surgical approach, operative outcomes, and complications were analyzed. From 2000 to 2013, 28 patients underwent bilateral adrenalectomy. Patient diagnoses included Cushing's disease (n = 19), pheochromocytoma (n = 7), and adrenal metastasis (n = 2). Of these 28 patients, successful laparoscopic adrenalectomy was performed in all but 2 patients. Twenty-three out of the 26 adrenalectomies were completed in a single stage, while three were performed as a staged approach due to deterioration in intraoperative respiratory status in two patients and patient body habitus in one. Of the adrenalectomies completed using the minimally invasive approach, a posterior retroperitoneal (PR) approach was performed in 17 patients and lateral transabdominal (LT) approach in 9 patients. Patients who underwent a LT approach had higher BMI, larger tumor size, and other concomitant intraabdominal pathology. Hospital stay for laparoscopic adrenalectomy was 3.5 days compared to 5 and 12 days for the two open cases. There were no 30-day hospital mortality and 5 patients had minor complications for the entire cohort. A minimally invasive operation is feasible in 93% of patients undergoing bilateral adrenalectomy with 65% of adrenalectomies performed using the PR approach. Indications for the LT approach include morbid obesity, tumor size >6 cm, and other concomitant intraabdominal pathology. Single-stage adrenalectomies are feasible in most patients, with prolonged operative time causing respiratory instability being the main indication for a staged approach.

  11. Hand-assisted versus straight laparoscopic sigmoid colectomy on a training simulator: what is the difference? A stepwise comparison of hand-assisted versus straight laparoscopic sigmoid colectomy performance on an augmented reality simulator.

    PubMed

    Leblanc, Fabien; Delaney, Conor P; Ellis, Clyde N; Neary, Paul C; Champagne, Bradley J; Senagore, Anthony J

    2010-12-01

    We hypothesized that simulator-generated metrics and intraoperative errors may be able to differentiate the technical differences between hand-assisted laparoscopic (HAL) and straight laparoscopic (SL) approaches. Thirty-eight trainees performed two laparoscopic sigmoid colectomies on an augmented reality simulator, randomly starting by a SL (n = 19) or HAL (n = 19) approach. Both approaches were compared according to simulator-generated metrics, and intraoperative errors were collected by faculty. Sixty-four percent of surgeons were experienced (>50 procedures) with open colon surgery. Fifty-five percent and 69% of surgeons were inexperienced (<10 procedures) with SL and HAL colon surgery, respectively. Time (P < 0.001), path length (P < 0.001), and smoothness (P < 0.001) were lower with the HAL approach. Operative times for sigmoid and splenic flexure mobilization and for the colorectal anastomosis were significantly shorter with the HAL approach. Time to control the vascular pedicle was similar between both approaches. Error rates were similar between both approaches. Operative time, path length, and smoothness correlated directly with the error rate for the HAL approach. In contrast, error rate inversely correlated with the operative time for the SL approach. A HAL approach for sigmoid colectomy accelerated colonic mobilization and anastomosis. The difference in correlation between both laparoscopic approaches and error rates suggests the need for different skills to perform the HAL and the SL sigmoid colectomy. These findings may explain the preference of some surgeons for a HAL approach early in the learning of laparoscopic colorectal surgery.

  12. Unmanned Aerial Systems Traffic Management (UTM): Safely Enabling UAS Operations in Low-Altitude Airspace

    NASA Technical Reports Server (NTRS)

    Jung, Jaewoo; Kopardekar, Parimal H.

    2016-01-01

    Flexibility where possible, and structure where necessary. Consider the needs of national security, safe airspace operations, economic opportunities, and emerging technologies. Risk-based approach based on population density, assets on the ground, density of operations, etc. Digital, virtual, dynamic, and as needed UTM services to manage operations.

  13. Unmanned Aerial Systems Traffic Management (UTM): Safely Enabling UAS Operations in Low-Altitude Airspace

    NASA Technical Reports Server (NTRS)

    Kopardekar, Parimal H.; Cavolowsky, John

    2015-01-01

    Flexibility where possible, and structure where necessary. Consider the needs of national security, safe airspace operations, economic opportunities, and emerging technologies. Risk-based approach based on population density, assets on the ground, density of operations, etc. Digital, virtual, dynamic, and as needed UTM services to manage operations.

  14. Hesitant fuzzy linguistic multicriteria decision-making method based on generalized prioritized aggregation operator.

    PubMed

    Wu, Jia-ting; Wang, Jian-qiang; Wang, Jing; Zhang, Hong-yu; Chen, Xiao-hong

    2014-01-01

    Based on linguistic term sets and hesitant fuzzy sets, the concept of hesitant fuzzy linguistic sets was introduced. The focus of this paper is the multicriteria decision-making (MCDM) problems in which the criteria are in different priority levels and the criteria values take the form of hesitant fuzzy linguistic numbers (HFLNs). A new approach to solving these problems is proposed, which is based on the generalized prioritized aggregation operator of HFLNs. Firstly, the new operations and comparison method for HFLNs are provided and some linguistic scale functions are applied. Subsequently, two prioritized aggregation operators and a generalized prioritized aggregation operator of HFLNs are developed and applied to MCDM problems. Finally, an illustrative example is given to illustrate the effectiveness and feasibility of the proposed method, which are then compared to the existing approach.

  15. Analysis of navigation and guidance requirements for commercial VTOL operations

    NASA Technical Reports Server (NTRS)

    Hoffman, W. C.; Zvara, J.; Hollister, W. M.

    1975-01-01

    The paper presents some results of a program undertaken to define navigation and guidance requirements for commercial VTOL operations in the takeoff, cruise, terminal and landing phases of flight in weather conditions up to and including Category III. Quantitative navigation requirements are given for the parameters range, coverage, operation near obstacles, horizontal accuracy, multiple landing aircraft, multiple pad requirements, inertial/radio-inertial requirements, reliability/redundancy, update rate, and data link requirements in all flight phases. A multi-configuration straw-man navigation and guidance system for commercial VTOL operations is presented. Operation of the system is keyed to a fully automatic approach for navigation, guidance and control, with pilot as monitor-manager. The system is a hybrid navigator using a relatively low-cost inertial sensor with DME updates and MLS in the approach/departure phases.

  16. A convergent diffusion and social marketing approach for disseminating proven approaches to physical activity promotion.

    PubMed

    Dearing, James W; Maibach, Edward W; Buller, David B

    2006-10-01

    Approaches from diffusion of innovations and social marketing are used here to propose efficient means to promote and enhance the dissemination of evidence-based physical activity programs. While both approaches have traditionally been conceptualized as top-down, center-to-periphery, centralized efforts at social change, their operational methods have usually differed. The operational methods of diffusion theory have a strong relational emphasis, while the operational methods of social marketing have a strong transactional emphasis. Here, we argue for a convergence of diffusion of innovation and social marketing principles to stimulate the efficient dissemination of proven-effective programs. In general terms, we are encouraging a focus on societal sectors as a logical and efficient means for enhancing the impact of dissemination efforts. This requires an understanding of complex organizations and the functional roles played by different individuals in such organizations. In specific terms, ten principles are provided for working effectively within societal sectors and enhancing user involvement in the processes of adoption and implementation.

  17. Hernia repair in the Lombardy region in 2000: preliminary results.

    PubMed

    Ferrante, F; Rusconi, A; Galimberti, A; Grassi, M

    2004-08-01

    Hernia repair is the most common surgical procedure in general surgery in Italy and in the Lombardy region. In the last decade, the use of mesh, the concept of a tension-free technique, and the postoperative rate of recurrences after Bassini or Shouldice operations have completely changed the surgical approach to hernia repair. For this reason, we sent a questionnaire to 148 surgical departments in the Lombardy region to investigate about total hernia operations performed in 2000 in Lombardy, the surgical approach, the surgical techniques used, the type of anesthesia and the hospital stay. One hundred five out of 148 surgical departments returned the questionnaire, and we collected information on a total of 16,935 surgical operations for hernia: 16,494 were performed using tension-free techniques. The inguinal anterior approach is the one of choice for primary and recurrent inguinal hernia, whereas the open preperitoneal and laparoscopic approaches are limited to bilateral and recurrent hernias. The majority of cases were treated under locoregional anesthesia and with a hospital stay of two nights.

  18. Definition of a Robust Supervisory Control Scheme for Sodium-Cooled Fast Reactors

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

    Ponciroli, R.; Passerini, S.; Vilim, R. B.

    In this work, an innovative control approach for metal-fueled Sodium-cooled Fast Reactors is proposed. With respect to the classical approach adopted for base-load Nuclear Power Plants, an alternative control strategy for operating the reactor at different power levels by respecting the system physical constraints is presented. In order to achieve a higher operational flexibility along with ensuring that the implemented control loops do not influence the system inherent passive safety features, a dedicated supervisory control scheme for the dynamic definition of the corresponding set-points to be supplied to the PID controllers is designed. In particular, the traditional approach based onmore » the adoption of tabulated lookup tables for the set-point definition is found not to be robust enough when failures of the implemented SISO (Single Input Single Output) actuators occur. Therefore, a feedback algorithm based on the Reference Governor approach, which allows for the optimization of reference signals according to the system operating conditions, is proposed.« less

  19. A description of the verbal behavior of students during two reading instruction methods

    PubMed Central

    Daly, Patricia M.

    1987-01-01

    The responses of students during two reading methods, the language experience approach and two Mastery Learning programs, were analyzed using verbal operants. A description of student responding was generated for these methods. The purpose of the study was to answer the questions: What are the major controlling variables determining student reading behavior during the language experience approach and two Mastery Learning programs, and how do these controlling variables change across story reading sessions and across stories in the first method? Student responses by verbal operant were compared for both reading methods. Findings indicated higher frequencies of textual operants occurred in responses during the Mastery Learning programs. A greater reliance on intraverbal control was evident in responses during the language experience approach. It is suggested that students who can generate strong intraverbal responses and who may have visual discrimination problems during early reading instruction may benefit from use of the language experience approach at this stage. ImagesFigure 2Figure 3 PMID:22477535

  20. A technical case report on use of tubular retractors for anterior cervical spine surgery.

    PubMed

    Kulkarni, Arvind G; Patel, Ankit; Ankith, N V

    2017-12-19

    The authors put-forth this technical report to establish the feasibility of performing an anterior cervical corpectomy and fusion (ACCF) and a two-level anterior cervical discectomy and fusion (ACDF) using a minimally invasive approach with tubular retractors. First case: cervical spondylotic myelopathy secondary to a large postero-inferiorly migrated disc treated with corpectomy and reconstruction with a mesh cage and locking plate. Second case: cervical disc herniation with radiculopathy treated with a two-level ACDF. Both cases were operated with minimally invasive approach with tubular retractor using a single incision. Technical aspects and clinical outcomes have been reported. No intra or post-operative complications were encountered. Intra-operative blood loss was negligible. The patients had a cosmetic scar on healing. Standard procedure of placement of tubular retractors is sufficient for adequate surgical exposure with minimal invasiveness. Minimally invasive approach to anterior cervical spine with tubular retractors is feasible. This is the first report on use of minimally invasive approach for ACCF and two-level ACDF.

  1. Modified trans-oral approach with an inferiorly based flap.

    PubMed

    Al-Holou, Wajd N; Park, Paul; Wang, Anthony C; Than, Khoi D; Marentette, Lawrence J

    2010-04-01

    The trans-oral approach allows direct access to pathologies of the anterior craniocervical junction. However, the classic midline incision of the posterior pharyngeal wall can be surgically burdensome and limits lateral exposure. We reviewed the medical records of nine patients undergoing the trans-oral approach. The sites of the pathology ranged from the clivus to C2, and surgical exposure ranged from the clivus to C3. Each operation utilized an inferiorly based flap. None of the patients experienced vascular or neurologic complications, and no patient had a cerebrospinal fluid fistula, pseudomeningocele, or meningitis postoperatively. The trans-oral approach with an inferiorly based flap can therefore be safely and effectively performed with minimal oropharyngeal and neurologic morbidity. Not only does a U-shaped flap allow adequate exposure from the lower half of the clivus to C3, a flap improves lateral exposure, provides a clear operating field, and allows superficial mucosal closure not directly overlying the operative field. (c) 2009 Elsevier Ltd. All rights reserved.

  2. Harvey Cushing's Approaches to Tumors in His Early Career: From the Skull Base to the Cranial Vault

    PubMed Central

    Pendleton, Courtney; Raza, Shaan M.; Gallia, Gary L.; Quiñones-Hinojosa, Alfredo

    2011-01-01

    In this report, we review Dr. Cushing's early surgical cases at the Johns Hopkins Hospital, revealing details of his early operative approaches to tumors of the skull base and cranial vault. Following Institutional Review Board approval, and through the courtesy of the Alan Mason Chesney Archives, we reviewed the Johns Hopkins Hospital surgical files from 1896 to 1912. Participants included four adult patients and one child who underwent surgical resection of bony tumors of the skull base and the cranial vault. The main outcome measures were operative approach and condition recorded at the time of discharge. The indications for surgery included unspecified malignant tumor of the basal meninges and temporal bone, basal cell carcinoma, osteoma of the posterior skull base, and osteomas of the frontal and parietofrontal cranial vault. While Cushing's experience with selected skull base pathology has been previously reported, the breadth of his contributions to operative approaches to the skull base has been neglected. PMID:22470271

  3. Limited sinus tarsi approach for intra-articular calcaneus fractures.

    PubMed

    Kikuchi, Christian; Charlton, Timothy P; Thordarson, David B

    2013-12-01

    Operative treatment of calcaneal fractures has a historically high rate of wound complications, so the most optimal operative approach has been a topic of investigation. This study reviews the radiographic and clinical outcomes of the use of the sinus tarsi approach for operative fixation of these fractures with attention to the rate of infection and restoration of angular measurements. The radiographs and charts of 20 patients with 22 calcaneal fractures were reviewed to assess for restoration of angular and linear dimensions of the calcaneus as well as time to radiographic union. Secondary outcome measures included the rate of postoperative infection, osteomyelitis, revision surgeries, and nonunion. We found a statistically significant restoration of Böhler's angle and calcaneal width. Three of the 22 cases had a superficial wound infection. One patient had revision surgery for symptomatic hardware removal. There were no events of osteomyelitis, deep infection, malunion, or nonunion. We found that the sinus tarsi approach yielded similar outcomes to those reported in the literature. Level IV, retrospective case series.

  4. Pterional approach versus unilateral frontal approach on tuberculum sellae meningioma: Single centre experiences

    PubMed Central

    Arifin, Muhammad Zafrullah; Mardjono, Ignatius; Sidabutar, Roland; Wirjomartani, Beny Atmadja; Faried, Ahmad

    2012-01-01

    Introduction: Tuberculum Sellae Meningioma is one of the most challenging surgeries among neurosurgeons. Many approaches have been established in the effort of removing the tumor and some of them are supported by an advanced neurosurgical technology. In this study, we aim to compare the efficacy of the two most common approaches, the pterional and the unilateral frontal. Materials and Methods: This was a restrospective study that aimed to observe the efficacy of the two most common approaches used in our center, the pterional and the unilateral frontal, in resecting the tuberculum sellae meningioma, which was held in Dr. Hasan Sadikin General Hospital, Bandung, from July 2007-July 2010. Twenty patients were enrolled with half of them operated by the pterional approach and the rest by unilateral frontal approach. We evaluated six parameters: tumor size, degree of tumor removal, surgery duration, post-operative cerebral edema, patients' outcome, and length of stay, which were evaluated to take measure of the efficacy of each procedure. Results: We found that the pterional approach gave more advantages than the unilateral frontal. Total tumor removal, especially in tumor size ≥ 3 cm was achieved in a greater number of subjects in the pterional (P<0.023). Other advantages of the pterional compared to the unilateral frontal were a shorter surgical duration (P=0.024), shorter length of stay (P=0.009) and less frequency of post-operative cerebral edema incidence (P=0.023). Conclusion: According to our facilities and conditions, it seems that the pterional approach have more advantages than the unilateral frontal approach in tuberculum sellae meningioma surgery. PMID:22639687

  5. 14 CFR 125.287 - Initial and recurrent pilot testing requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... TRANSPORTATION (CONTINUED) AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION AND OPERATIONS... air navigation aids appropriate to the operation of pilot authorization, including, when applicable, instrument approach facilities and procedures; (5) Air traffic control procedures, including IFR procedures...

  6. 7 CFR 610.23 - State Technical Committee meetings.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Technical Committee member. (b) NRCS will establish and maintain national standard operating procedures... standard operating procedures will outline items such as: The best practice approach to establishing... standard operating procedures established under paragraph (b) of this section, the State Conservationist...

  7. 7 CFR 610.23 - State Technical Committee meetings.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Technical Committee member. (b) NRCS will establish and maintain national standard operating procedures... standard operating procedures will outline items such as: The best practice approach to establishing... standard operating procedures established under paragraph (b) of this section, the State Conservationist...

  8. 7 CFR 610.23 - State Technical Committee meetings.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Technical Committee member. (b) NRCS will establish and maintain national standard operating procedures... standard operating procedures will outline items such as: The best practice approach to establishing... standard operating procedures established under paragraph (b) of this section, the State Conservationist...

  9. 7 CFR 610.23 - State Technical Committee meetings.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Technical Committee member. (b) NRCS will establish and maintain national standard operating procedures... standard operating procedures will outline items such as: The best practice approach to establishing... standard operating procedures established under paragraph (b) of this section, the State Conservationist...

  10. 7 CFR 610.23 - State Technical Committee meetings.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Technical Committee member. (b) NRCS will establish and maintain national standard operating procedures... standard operating procedures will outline items such as: The best practice approach to establishing... standard operating procedures established under paragraph (b) of this section, the State Conservationist...

  11. Setting Cut Scores on an EFL Placement Test Using the Prototype Group Method: A Receiver Operating Characteristic (ROC) Analysis

    ERIC Educational Resources Information Center

    Eckes, Thomas

    2017-01-01

    This paper presents an approach to standard setting that combines the prototype group method (PGM; Eckes, 2012) with a receiver operating characteristic (ROC) analysis. The combined PGM-ROC approach is applied to setting cut scores on a placement test of English as a foreign language (EFL). To implement the PGM, experts first named learners whom…

  12. Swarming Unmanned Aircraft Systems

    DTIC Science & Technology

    2008-09-01

    systems may become a viable part of strategy and tactics in the future. Specific to Unmanned Aircraft Sys- tems ( UAS ). they see a strong and central...system itself. They do not want to limit direct access to only Military Occupational Specialty (MOS) trained UAS operators. Rather, they feel that...Collaborating (SASC) characteristics within swarms of UAS that support operations. Technical Approach The approach taken to model this system begins with an

  13. Constraint Embedding for Multibody System Dynamics

    NASA Technical Reports Server (NTRS)

    Jain, Abhinandan

    2009-01-01

    This paper describes a constraint embedding approach for the handling of local closure constraints in multibody system dynamics. The approach uses spatial operator techniques to eliminate local-loop constraints from the system and effectively convert the system into tree-topology systems. This approach allows the direct derivation of recursive O(N) techniques for solving the system dynamics and avoiding the expensive steps that would otherwise be required for handling the closedchain dynamics. The approach is very effective for systems where the constraints are confined to small-subgraphs within the system topology. The paper provides background on the spatial operator O(N) algorithms, the extensions for handling embedded constraints, and concludes with some examples of such constraints.

  14. A neural network strategy for end-point optimization of batch processes.

    PubMed

    Krothapally, M; Palanki, S

    1999-01-01

    The traditional way of operating batch processes has been to utilize an open-loop "golden recipe". However, there can be substantial batch to batch variation in process conditions and this open-loop strategy can lead to non-optimal operation. In this paper, a new approach is presented for end-point optimization of batch processes by utilizing neural networks. This strategy involves the training of two neural networks; one to predict switching times and the other to predict the input profile in the singular region. This approach alleviates the computational problems associated with the classical Pontryagin's approach and the nonlinear programming approach. The efficacy of this scheme is illustrated via simulation of a fed-batch fermentation.

  15. Evaluation of a Head-Worn Display System as an Equivalent Head-Up Display for Low Visibility Commercial Operations

    NASA Technical Reports Server (NTRS)

    Arthur, Jarvis (Trey) J., III; Shelton, Kevin J.; Prinzel, Lawrence J.; Nicholas, Stephanie N.; Williams, Steven P.; Ellis, Kyle E.; Jones, Denise R.; Bailey, Randall E.; Harrison, Stephanie J.; Barnes, James R.

    2017-01-01

    Research, development, test, and evaluation of fight deck interface technologies is being conducted by the National Aeronautics and Space Administration (NASA) to proactively identify, develop, and mature tools, methods, and technologies for improving overall aircraft safety of new and legacy vehicles operating in the Next Generation Air Transportation System (NextGen). One specific area of research was the use of small Head-Worn Displays (HWDs) to serve as a possible equivalent to a Head-Up Display (HUD). A simulation experiment and a fight test were conducted to evaluate if the HWD can provide an equivalent level of performance to a HUD. For the simulation experiment, airline crews conducted simulated approach and landing, taxi, and departure operations during low visibility operations. In a follow-on fight test, highly experienced test pilots evaluated the same HWD during approach and surface operations. The results for both the simulation and fight tests showed that there were no statistical differences in the crews' performance in terms of approach, touchdown and takeoff; but, there are still technical hurdles to be overcome for complete display equivalence including, most notably, the end-to-end latency of the HWD system.

  16. Hemorrhoids: From basic pathophysiology to clinical management

    PubMed Central

    Lohsiriwat, Varut

    2012-01-01

    This review discusses the pathophysiology, epidemiology, risk factors, classification, clinical evaluation, and current non-operative and operative treatment of hemorrhoids. Hemorrhoids are defined as the symptomatic enlargement and distal displacement of the normal anal cushions. The most common symptom of hemorrhoids is rectal bleeding associated with bowel movement. The abnormal dilatation and distortion of the vascular channel, together with destructive changes in the supporting connective tissue within the anal cushion, is a paramount finding of hemorrhoids. It appears that the dysregulation of the vascular tone and vascular hyperplasia might play an important role in hemorrhoidal development, and could be a potential target for medical treatment. In most instances, hemorrhoids are treated conservatively, using many methods such as lifestyle modification, fiber supplement, suppository-delivered anti-inflammatory drugs, and administration of venotonic drugs. Non-operative approaches include sclerotherapy and, preferably, rubber band ligation. An operation is indicated when non-operative approaches have failed or complications have occurred. Several surgical approaches for treating hemorrhoids have been introduced including hemorrhoidectomy and stapled hemorrhoidopexy, but postoperative pain is invariable. Some of the surgical treatments potentially cause appreciable morbidity such as anal stricture and incontinence. The applications and outcomes of each treatment are thoroughly discussed. PMID:22563187

  17. Hemorrhoids: from basic pathophysiology to clinical management.

    PubMed

    Lohsiriwat, Varut

    2012-05-07

    This review discusses the pathophysiology, epidemiology, risk factors, classification, clinical evaluation, and current non-operative and operative treatment of hemorrhoids. Hemorrhoids are defined as the symptomatic enlargement and distal displacement of the normal anal cushions. The most common symptom of hemorrhoids is rectal bleeding associated with bowel movement. The abnormal dilatation and distortion of the vascular channel, together with destructive changes in the supporting connective tissue within the anal cushion, is a paramount finding of hemorrhoids. It appears that the dysregulation of the vascular tone and vascular hyperplasia might play an important role in hemorrhoidal development, and could be a potential target for medical treatment. In most instances, hemorrhoids are treated conservatively, using many methods such as lifestyle modification, fiber supplement, suppository-delivered anti-inflammatory drugs, and administration of venotonic drugs. Non-operative approaches include sclerotherapy and, preferably, rubber band ligation. An operation is indicated when non-operative approaches have failed or complications have occurred. Several surgical approaches for treating hemorrhoids have been introduced including hemorrhoidectomy and stapled hemorrhoidopexy, but postoperative pain is invariable. Some of the surgical treatments potentially cause appreciable morbidity such as anal stricture and incontinence. The applications and outcomes of each treatment are thoroughly discussed.

  18. Learning curve in transradial cardiac catheterization: procedure-related parameters stratified by operators' transradial volume.

    PubMed

    Kasasbeh, Ehab S; Parvez, Babar; Huang, Robert L; Hasselblad, Michele Marie; Glazer, Mark D; Salloum, Joseph G; Cleator, John H; Zhao, David X

    2012-11-01

    To determine whether radial artery access is associated with a reduction in fluoroscopy time, procedure time, and other procedural variables over a 27-month period during which the radial artery approach was incorporated in a single academic Medical Center. Although previous studies have demonstrated a relationship between increased volume and decreased procedural time, no studies have looked at the integration of radial access over time. Data were collected from consecutive patients who presented to the Vanderbilt University Medical Center cardiac catheterization laboratory from January 1, 2009 to April 1, 2011. Patients who underwent radial access diagnostic catheterization with and without percutaneous coronary intervention were included in this study. A total of 1112 diagnostic cardiac catheterizations through the radial access site were analyzed. High-volume, intermediate-volume, and low-volume operators were grouped based on the percentage of procedures performed through a radial approach. From 2009 to 2011, there was a significant decrease in fluoroscopy time in all operator groups for diagnostic catheterization (P=.035). The high-volume operator group had 1.88 and 3.66 minute reductions in fluoroscopy time compared to the intermediate- and low-volume operator groups, respectively (both P<.001). Likewise, the intermediate-volume operator group had a 1.77 minute improvement compared to the low-volume operator group, but this did not reach statistical significance (P=.102). The improvement in fluoroscopy time and other procedure-related parameters was seen after approximately 25 cases with further improvement after 75 cases. The incorporation of the radial access approach in the cardiac catheterization laboratory led to a decrease in fluoroscopy time for each operator and operator group over the last 3 years. Our data demonstrated that higher-volume radial operators have better procedure, room, and fluoroscopy times when compared to intermediate- and low-volume operators. However, lower-volume operators have a reduction in procedure-related parameters with increased radial cases. Number of procedures needed to become sufficient was demonstrated in the current study.

  19. [Clinical studies of pedicle screw-rod fixation of thoracolumbar burst fractures through posterior unilateral approach after vertebrae corpectomy fusion].

    PubMed

    Hua, Yong-jun; Wang, Ren-yan; Guo, Zhi-hui; Shu, Cun-hong; Li, Chao-hua

    2016-01-01

    To compare the clinical curative effect of thoracolumbar burst fracture treated by the posterior unilateral approach corpectomy fusion screw-rod fixation and anterior corpectomy bone fusion screw plate fixation. From January 2008 to May 2014,36 cases of thoracolumbar burst fracture underwent operation of decompression, fusion, and internal fixation was retrospective analyzed. Among them, 16 patients were treated through posterior approach as posterior group, including 13 males and 3 females aged from 37 to 62 years old; 9 cases caused by falling injury, 3 cases by traffic accident injury,4 cases by heavy aboved;the injury segment was on T₁₂ in 2 cases, L₁ in 5 cases, L₂ in 7 cases, L₃ in 2 cases; according ASIA grade, 3 cases were grade A, 2 cases were grade B, 2 cases were grade C, 5 cases were grade D, 4 cases were grade E; the time between injury and operation ranged from 5 to 15 days. Other 20 patients were treated through anterior-lateral approach as anterior-lateral group, including 15 males and 5 females with age from 27 to 62 years old; 12 cases caused by falling injury, 4 cases by traffic accident injury, 4 cases by heavy aboved; the injury segment was on T₁₂ in 2 cases, L₁, in 7 cases, L₂ in 9 cases, L₃ in 2 cases; for ASIA grade: 4 cases were grade A, 2 cases were grade B, 4 cases were grade C, 6 cases were grade D, 4 cases were grade E; the time between injury and operation ranged from 4 to 12 days. The operation time, bleeding during operation and postoperative drainage volume were observed in two groups,and the changes of nerve function of ASIA grade, clinical efficacy,improved degree of thoracic and lumbar lordosis,and bony fusion were compared between two groups. All patients were followed up from 12 to 24 months with an average of (15.8 ± 3.3) months. The operation time, bleeding during operation, and postoperative drainage volume had no significant different between two groups (P > 0.05). As compared with preoperative, ASIA grade of two groups at last follow-up had statistically significantly different (P < 0.01), the neural function of two groups after operation was recovered for different extent. The JOA score of two groups was compared between last follow-up and preoperative, the difference had statistically significant (P < 0.01), the two groups showed good clinical effect. The clinical results of ASIA grade, JOA score and RIS had no significant differences between two groups. All patients of two groups were obtained fusion. Thoracic and lumbar lordosis angle improvement degree had no significant difference between two groups ,it bad significant difference had statistical significance compared with preoperative, the two approaches could effectively restore the spinal sequence. For patients with thoracolumbar burst fracture just treated by anterior decompression and reconstruction of anterior column, according to the degree of operation performer' skill proficiency and the patient' condition to choose, but for patients must performed the spinal canal decompression anterior and posterior, the three column-reconstruction to required anterior-posterior approach, the posterior unilateral approach corpectomy fusion screw-rod fixation obviously shorten operation time, reduce the operation wound, it is worth the clinical promotion.

  20. A distributed computing approach to mission operations support. [for spacecraft

    NASA Technical Reports Server (NTRS)

    Larsen, R. L.

    1975-01-01

    Computing mission operation support includes orbit determination, attitude processing, maneuver computation, resource scheduling, etc. The large-scale third-generation distributed computer network discussed is capable of fulfilling these dynamic requirements. It is shown that distribution of resources and control leads to increased reliability, and exhibits potential for incremental growth. Through functional specialization, a distributed system may be tuned to very specific operational requirements. Fundamental to the approach is the notion of process-to-process communication, which is effected through a high-bandwidth communications network. Both resource-sharing and load-sharing may be realized in the system.

  1. Solving fractional optimal control problems within a Chebyshev-Legendre operational technique

    NASA Astrophysics Data System (ADS)

    Bhrawy, A. H.; Ezz-Eldien, S. S.; Doha, E. H.; Abdelkawy, M. A.; Baleanu, D.

    2017-06-01

    In this manuscript, we report a new operational technique for approximating the numerical solution of fractional optimal control (FOC) problems. The operational matrix of the Caputo fractional derivative of the orthonormal Chebyshev polynomial and the Legendre-Gauss quadrature formula are used, and then the Lagrange multiplier scheme is employed for reducing such problems into those consisting of systems of easily solvable algebraic equations. We compare the approximate solutions achieved using our approach with the exact solutions and with those presented in other techniques and we show the accuracy and applicability of the new numerical approach, through two numerical examples.

  2. Impact of composites on future transport aircraft

    NASA Technical Reports Server (NTRS)

    Kinder, Robert H.

    1993-01-01

    In the current environment, new technology must be cost-effective in addition to improving operability. Various approaches have been used to determine the 'hurdle' or 'breakthrough' return that must be achieved to gain customer commitment for a new product or aircraft, or in this case, a new application of the technology. These approaches include return-on-investment, payback period, and addition to net worth. An easily understood figure-of-merit and one used by our airline customers is improvement in direct operating cost per seat-mile. Any new technology must buy its way onto the aircraft through reduction in direct operating cost (DOC).

  3. Consideration of Fuel Requirements for Supersonic Transport Operation

    NASA Technical Reports Server (NTRS)

    Stickle, Joseph W.

    1965-01-01

    An analysis of the interaction of operational environment and aircraft characteristics of the supersonic transport (SST) in the areas of design-range and reserve-fuel requirements has been made. Design-range requirements are considered in relation to the effects of wind, temperature, flight-level assignment, and payload variation. An approach toward combining en route and holding reserve requirements while maintaining protection equivalent to that provided subsonic jet transport operations by the present civil air regulation en route plus holding reserves is given. This approach results in a savings in reserve fuel over that required by separate requirements.

  4. Symptomatic iliofemoral deep venous thrombosis treated with hybrid operative thrombectomy.

    PubMed

    Rodríguez, Limael E; Aponte-Rivera, Francisco; Figueroa-Vicente, Ricardo; Bolanos-Avila, Guillermo E; Martínez-Trabal, Jorge L

    2015-10-01

    During the past 15 years, strategies that promote immediate and complete thrombus removal have gained popularity for the treatment of acute-onset iliofemoral deep venous thrombosis. In this case report, we describe a novel operative approach to venous thrombus removal known as hybrid operative thrombectomy. The technique employs a direct inguinal approach with concomitant retrograde advancement of a balloon catheter by femoral venotomy. Moreover, it provides effective thrombus removal through a single incision, with or without stent placement, and has the advantage of a completion venogram. Copyright © 2015 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  5. Morphological operators for enhanced polarimetric image target detection

    NASA Astrophysics Data System (ADS)

    Romano, João. M.; Rosario, Dalton S.

    2015-09-01

    We introduce an algorithm based on morphological filters with the Stokes parameters that augments the daytime and nighttime detection of weak-signal manmade objects immersed in a predominant natural background scene. The approach features a tailored sequence of signal-enhancing filters, consisting of core morphological operators (dilation, erosion) and higher level morphological operations (e.g., spatial gradient, opening, closing) to achieve a desired overarching goal. Using representative data from the SPICE database, the results show that the approach was able to automatically and persistently detect with a high confidence level the presence of three mobile military howitzer surrogates (targets) in natural clutter.

  6. Spacelab user implementation assessment study (software requirements analysis). Volume 1: Executive study

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The primary objective of this study was to develop an integrated approach for the development, implementation, and utilization of all software that is required to efficiently and cost-effectively support advanced technology laboratory flight and ground operations. It was recognized that certain aspects of the operations would be mandatory computerized services; computerization of other aspects would be optional. Thus, the analyses encompassed not only alternate computer utilization and implementations but trade studies of the programmatic effects of non-computerized versus computerized approaches to the operations. A general overview of the study is presented.

  7. Better Redd than Dead: Optimizing Reservoir Operations for Wild Fish Survival During Drought

    NASA Astrophysics Data System (ADS)

    Adams, L. E.; Lund, J. R.; Quiñones, R.

    2014-12-01

    Extreme droughts are difficult to predict and may incur large economic and ecological costs. Dam operations in drought usually consider minimizing economic costs. However, dam operations also offer an opportunity to increase wild fish survival under difficult conditions. Here, we develop a probabilistic optimization approach to developing reservoir release schedules to maximize fish survival in regulated rivers. A case study applies the approach to wild Fall-run Chinook Salmon below Folsom Dam on California's American River. Our results indicate that releasing more water early in the drought will, on average, save more wild fish over the long term.

  8. Modular Software Interfaces for Revolutionary Flexibility in Space Operations

    NASA Technical Reports Server (NTRS)

    Glass, Brian; Braham, Stephen; Pollack, Jay

    2005-01-01

    To make revolutionary improvements in exploration, space systems need to be flexible, realtime reconfigurable, and able to trade data transparently among themselves and mission operations. Onboard operations systems, space assembly coordination and EVA systems in exploration and construction all require real-time modular reconfigurability and data sharing. But NASA's current exploration systems are still largely legacies from hastily-developed, one-off Apollo-era practices. Today's rovers, vehicles, spacesuits, space stations, and instruments are not able to plug-and-play, Lego-like: into different combinations. Point-to-point dominates - individual suit to individual vehicle, individual instrument to rover. All are locally optimized, all unique, each of the data interfaces has been recoded for each possible combination. This will be an operations and maintenance nightmare in the much larger Project Constellation system of systems. This legacy approach does not scale to the hundreds of networked space components needed for space construction and for new, space-based approaches to Earth-Moon operations. By comparison, battlefield information management systems, which are considered critical to military force projection, have long since abandoned a point-to-point approach to systems integration. From a system-of-systems viewpoint, a clean-sheet redesign of the interfaces of all exploration systems is a necessary prerequisite before designing the interfaces of the individual exploration systems. Existing communications and Global Information Grid and middleware technologies are probably sufficient for command and control and information interfaces, with some hardware and time-delay modifications for space environments. NASA's future advanced space operations must also be information and data compatible with aerospace operations and surveillance systems being developed by other US Government agencies such as the Department of Homeland Security, Federal Aviation Administration and Department of Defense. This paper discusses fundamental system-of-systems infrastructure: approaches and architectures for modular plug-and-play software interfaces for revolutionary improvements in flexibility, modularity, robustness, ease of maintenance, reconfigurability, safety and productivity. Starting with middleware, databases, and mobile communications technologies, our technical challenges will be to apply these ideas to the requirements of constellations of space systems and to implement them initially on prototype space hardware. This is necessary to demonstrate an integrated information sharing architecture and services. It is a bottom-up approach, one that solves the problem of space operations data integration. Exploration demands uniform software mechanisms for application information interchange, and the corresponding uniformly available software services to enhance these mechanisms. We will examine the issues in plug-and-play, real-time-configurable systems, including common definition and management and tracking of data and information among many different space systems. Different field test approaches are discussed, including the use of the International Space Station and terrestrial analog mission operations at field sites.

  9. A more fundamental approach to the derivation of nonlinear acoustic wave equations with fractional loss operators (L).

    PubMed

    Prieur, Fabrice; Vilenskiy, Gregory; Holm, Sverre

    2012-10-01

    A corrected derivation of nonlinear wave propagation equations with fractional loss operators is presented. The fundamental approach is based on fractional formulations of the stress-strain and heat flux definitions but uses the energy equation and thermodynamic identities to link density and pressure instead of an erroneous fractional form of the entropy equation as done in Prieur and Holm ["Nonlinear acoustic wave equations with fractional loss operators," J. Acoust. Soc. Am. 130(3), 1125-1132 (2011)]. The loss operator of the obtained nonlinear wave equations differs from the previous derivations as well as the dispersion equation, but when approximating for low frequencies the expressions for the frequency dependent attenuation and velocity dispersion remain unchanged.

  10. Entry, Descent, and Landing Operations Analysis for the Mars Phoenix Lander

    NASA Technical Reports Server (NTRS)

    Prince, Jill L.; Desai, Prasun N.; Queen, Eric M.; Grover, Myron R.

    2008-01-01

    The Mars Phoenix lander was launched August 4, 2007 and remained in cruise for ten months before landing in the northern plains of Mars in May 2008. The one-month Entry, Descent, and Landing (EDL) operations phase prior to entry consisted of daily analyses, meetings, and decisions necessary to determine if trajectory correction maneuvers and environmental parameter updates to the spacecraft were required. An overview of the Phoenix EDL trajectory simulation and analysis that was performed during the EDL approach and operations phase is described in detail. The evolution of the Monte Carlo statistics and footprint ellipse during the final approach phase is also provided. The EDL operations effort accurately delivered the Phoenix lander to the desired landing region on May 25, 2008.

  11. Extracting important information from Chinese Operation Notes with natural language processing methods.

    PubMed

    Wang, Hui; Zhang, Weide; Zeng, Qiang; Li, Zuofeng; Feng, Kaiyan; Liu, Lei

    2014-04-01

    Extracting information from unstructured clinical narratives is valuable for many clinical applications. Although natural Language Processing (NLP) methods have been profoundly studied in electronic medical records (EMR), few studies have explored NLP in extracting information from Chinese clinical narratives. In this study, we report the development and evaluation of extracting tumor-related information from operation notes of hepatic carcinomas which were written in Chinese. Using 86 operation notes manually annotated by physicians as the training set, we explored both rule-based and supervised machine-learning approaches. Evaluating on unseen 29 operation notes, our best approach yielded 69.6% in precision, 58.3% in recall and 63.5% F-score. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Conflict Prevention and Separation Assurance Method in the Small Aircraft Transportation System

    NASA Technical Reports Server (NTRS)

    Consiglio, Maria C.; Carreno, Victor A.; Williams, Daniel M.; Munoz, Cesar

    2005-01-01

    A multilayer approach to the prevention of conflicts due to the loss of aircraft-to-aircraft separation which relies on procedures and on-board automation was implemented as part of the SATS HVO Concept of Operations. The multilayer system gives pilots support and guidance during the execution of normal operations and advance warning for procedure deviations or off-nominal operations. This paper describes the major concept elements of this multilayer approach to separation assurance and conflict prevention and provides the rationale for its design. All the algorithms and functionality described in this paper have been implemented in an aircraft simulation in the NASA Langley Research Center s Air Traffic Operation Lab and on the NASA Cirrus SR22 research aircraft.

  13. Numerical Methods for Nonlinear Fokker-Planck Collision Operator in TEMPEST

    NASA Astrophysics Data System (ADS)

    Kerbel, G.; Xiong, Z.

    2006-10-01

    Early implementations of Fokker-Planck collision operator and moment computations in TEMPEST used low order polynomial interpolation schemes to reuse conservative operators developed for speed/pitch-angle (v, θ) coordinates. When this approach proved to be too inaccurate we developed an alternative higher order interpolation scheme for the Rosenbluth potentials and a high order finite volume method in TEMPEST (,) coordinates. The collision operator is thus generated by using the expansion technique in (v, θ) coordinates for the diffusion coefficients only, and then the fluxes for the conservative differencing are computed directly in the TEMPEST (,) coordinates. Combined with a cut-cell treatment at the turning-point boundary, this new approach is shown to have much better accuracy and conservation properties.

  14. Evaluation of three-dimensional printing for internal fixation of unstable pelvic fracture from minimal invasive para-rectus abdominis approach: a preliminary report.

    PubMed

    Zeng, Canjun; Xiao, Jidong; Wu, Zhanglin; Huang, Wenhua

    2015-01-01

    The aim of this study is to evaluate the efficacy and feasibility of three-dimensional printing (3D printing) assisted internal fixation of unstable pelvic fracture from minimal invasive para-rectus abdominis approach. A total of 38 patients with unstable pelvic fractures were analyzed retrospectively from August 2012 to February 2014. All cases were treated operatively with internal fixation assisted by three-dimensional printing from minimal invasive para-rectus abdominis approach. Both preoperative CT and three-dimensional reconstruction were performed. Pelvic model was created by 3D printing. Data including the best entry points, plate position and direction and length of screw were obtained from simulated operation based on 3D printing pelvic model. The diaplasis and internal fixation were performed by minimal invasive para-rectus abdominis approach according to the optimized dada in real surgical procedure. Matta and Majeed score were used to evaluate currative effects after operation. According to the Matta standard, the outcome of the diaplasis achieved 97.37% with excellent and good. Majeed assessment showed 94.4% with excellent and good. The imageological examination showed consistency of internal fixation and simulated operation. The mean operation time was 110 minutes, mean intraoperative blood loss 320 ml, and mean incision length 6.5 cm. All patients have achieved clinical healing, with mean healing time of 8 weeks. Three-dimensional printing assisted internal fixation of unstable pelvic fracture from minimal invasive para-rectus abdominis approach is feasible and effective. This method has the advantages of trauma minimally, bleeding less, healing rapidly and satisfactory reduction, and worthwhile for spreading in clinical practice.

  15. Assessment of the financial implications for laparoscopic liver surgery: a single-centre UK cost analysis for minor and major hepatectomy.

    PubMed

    Abu Hilal, Mohammed; Di Fabio, Francesco; Syed, Shareef; Wiltshire, Robert; Dimovska, Eleonora; Turner, David; Primrose, John N; Pearce, Neil W

    2013-07-01

    Laparoscopic hepatectomy is progressively gaining popularity. However, it is still unclear whether the laparoscopic approach offers cost advantages compared with the open approach, especially when major hepatectomies are required. Data providing useful insights into the costs of the laparoscopic approach for clinicians and hospitals are needed. The aim of this study is to assess the financial implications of the laparoscopic approach for two standardized minor and major hepatectomies: left lateral sectionectomy and right hepatectomy. A cost comparison analysis of patients undergoing laparoscopic right hepatectomy (LRH) and laparoscopic left lateral sectionectomy (LLLS) versus the open counterparts was performed. Data considered for the comparison analysis were operative costs (theatre cost, consumables and surgeon/anaesthetic labour cost), postoperative costs (hospital stay, complication management and readmissions) and overall costs. A total of 149 patients were included: 38 patients underwent LRH and 46 open right hepatectomy (ORH); 46 patients underwent LLLS and 19 open left lateral sectionectomy (OLLS). For LRH the mean operative, postoperative and overall costs were £10,181, £4,037 and £14,218; for ORH the mean operative, postoperative and overall costs were £6,483 (p < 0.0001), £10,304 (p < 0.0001) and £16,787 (p = 0.886). Regarding LLLS, the mean operative, postoperative and overall costs were £5,460, £2,599 and £8,059; for OLLS the mean operative, postoperative and overall costs were £5,841 (p = 0.874), £5,796 (p < 0.0001) and £11,637 (p = 0.0001). Our data support the cost advantage of the laparoscopic approach for left lateral sectionectomy and the cost neutrality for right hepatectomy.

  16. Power grid operation risk management: V2G deployment for sustainable development

    NASA Astrophysics Data System (ADS)

    Haddadian, Ghazale J.

    The production, transmission, and delivery of cost--efficient energy to supply ever-increasing peak loads along with a quest for developing a low-carbon economy require significant evolutions in the power grid operations. Lower prices of vast natural gas resources in the United States, Fukushima nuclear disaster, higher and more intense energy consumptions in China and India, issues related to energy security, and recent Middle East conflicts, have urged decisions makers throughout the world to look into other means of generating electricity locally. As the world look to combat climate changes, a shift from carbon-based fuels to non-carbon based fuels is inevitable. However, the variability of distributed generation assets in the electricity grid has introduced major reliability challenges for power grid operators. While spearheading sustainable and reliable power grid operations, this dissertation develops a multi-stakeholder approach to power grid operation design; aiming to address economic, security, and environmental challenges of the constrained electricity generation. It investigates the role of Electric Vehicle (EV) fleets integration, as distributed and mobile storage assets to support high penetrations of renewable energy sources, in the power grid. The vehicle-to-grid (V2G) concept is considered to demonstrate the bidirectional role of EV fleets both as a provider and consumer of energy in securing a sustainable power grid operation. The proposed optimization modeling is the application of Mixed-Integer Linear Programing (MILP) to large-scale systems to solve the hourly security-constrained unit commitment (SCUC) -- an optimal scheduling concept in the economic operation of electric power systems. The Monte Carlo scenario-based approach is utilized to evaluate different scenarios concerning the uncertainties in the operation of power grid system. Further, in order to expedite the real-time solution of the proposed approach for large-scale power systems, it considers a two-stage model using the Benders Decomposition (BD). The numerical simulation demonstrate that the utilization of smart EV fleets in power grid systems would ensure a sustainable grid operation with lower carbon footprints, smoother integration of renewable sources, higher security, and lower power grid operation costs. The results, additionally, illustrate the effectiveness of the proposed MILP approach and its potentials as an optimization tool for sustainable operation of large scale electric power systems.

  17. STATISTICS-BASED APPROACH TO WASTEWATER TREATMENT PLANT OPERATIONS

    EPA Science Inventory

    This paper describes work toward development of a convenient decision support system to improve everyday operation and control of the wastewater treatment process. The goal is to help the operator detect problems in the process and select appropriate control actions. The system...

  18. An examination of the operational error database for air route traffic control centers.

    DOT National Transportation Integrated Search

    1993-12-01

    Monitoring the frequency and determining the causes of operational errors - defined as the loss of prescribed separation between aircraft - is one approach to assessing the operational safety of the air traffic control system. The Federal Aviation Ad...

  19. Endoscope-assisted approach to excision of branchial cleft cysts.

    PubMed

    Teng, Stephanie E; Paul, Benjamin C; Brumm, John D; Fritz, Mark; Fang, Yixin; Myssiorek, David

    2016-06-01

    The purpose of this study is to describe an endoscope-assisted surgical technique for the excision of branchial cleft cysts and compare it to the standard approach. Retrospective case series review. Twenty-seven cases described as branchial cleft excisions performed by a single surgeon at one academic medical center were identified between 2007 and 2014. Twenty-five cases (8 endoscopic, 17 standard approach) were included in the study. Cases were excluded if final pathology was malignant. Patient charts were reviewed, and two techniques were compared through analysis of incision size, operative time, and surgical outcomes. This study showed that the length of incision required for the endoscopic approach (mean = 2.13 ± 0.23) was significantly less than that of the standard approach (mean = 4.10 ± 1.46, P = 0.008) despite the fact that there was no significant difference in cyst size between the two groups (P = 0.09). The other variables examined, including operative time and surgical outcomes, were not significantly different between the two groups. This transcervical endoscope-assisted approach to branchial cleft cyst excision is a viable option for uncomplicated cases. It provides better cosmetic results than the standard approach and does not negatively affect outcomes, increase operative time, or result in recurrence. 4. Laryngoscope, 126:1339-1342, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.

  20. Application of System Operational Effectiveness Methodology to Space Launch Vehicle Development and Operations

    NASA Technical Reports Server (NTRS)

    Watson, Michael D.; Kelley, Gary W.

    2012-01-01

    The Department of Defense (DoD) defined System Operational Effectiveness (SOE) model provides an exceptional framework for an affordable approach to the development and operation of space launch vehicles and their supporting infrastructure. The SOE model provides a focal point from which to direct and measure technical effectiveness and process efficiencies of space launch vehicles. The application of the SOE model to a space launch vehicle's development and operation effort leads to very specific approaches and measures that require consideration during the design phase. This paper provides a mapping of the SOE model to the development of space launch vehicles for human exploration by addressing the SOE model key points of measurement including System Performance, System Availability, Technical Effectiveness, Process Efficiency, System Effectiveness, Life Cycle Cost, and Affordable Operational Effectiveness. In addition, the application of the SOE model to the launch vehicle development process is defined providing the unique aspects of space launch vehicle production and operations in lieu of the traditional broader SOE context that examines large quantities of fielded systems. The tailoring and application of the SOE model to space launch vehicles provides some key insights into the operational design drivers, capability phasing, and operational support systems.

  1. Flexible alpha allocation strategies for confirmatory adaptive enrichment clinical trials with a prespecified subgroup.

    PubMed

    Sugitani, Toshifumi; Posch, Martin; Bretz, Frank; Koenig, Franz

    2018-06-26

    Adaptive enrichment designs have recently received considerable attention as they have the potential to make drug development process for personalized medicine more efficient. Several statistical approaches have been proposed so far in the literature and the operating characteristics of these approaches are extensively investigated using simulation studies. In this paper, we improve on existing adaptive enrichment designs by assigning unequal weights to the significance levels associated with the hypotheses of the overall population and a prespecified subgroup. More specifically, we focus on the standard combination test, a modified combination test, the marginal combination test, and the partial conditional error rate approach and explore the operating characteristics of these approaches by a simulation study. We show that these approaches can lead to power gains, compared to existing approaches, if the weights are chosen carefully. © 2018 John Wiley & Sons, Ltd.

  2. MPI Runtime Error Detection with MUST: Advances in Deadlock Detection

    DOE PAGES

    Hilbrich, Tobias; Protze, Joachim; Schulz, Martin; ...

    2013-01-01

    The widely used Message Passing Interface (MPI) is complex and rich. As a result, application developers require automated tools to avoid and to detect MPI programming errors. We present the Marmot Umpire Scalable Tool (MUST) that detects such errors with significantly increased scalability. We present improvements to our graph-based deadlock detection approach for MPI, which cover future MPI extensions. Our enhancements also check complex MPI constructs that no previous graph-based detection approach handled correctly. Finally, we present optimizations for the processing of MPI operations that reduce runtime deadlock detection overheads. Existing approaches often require ( p ) analysis time permore » MPI operation, for p processes. We empirically observe that our improvements lead to sub-linear or better analysis time per operation for a wide range of real world applications.« less

  3. Operational Approach to Generalized Coherent States

    NASA Technical Reports Server (NTRS)

    DeMartino, Salvatore; DeSiena, Silvio

    1996-01-01

    Generalized coherent states for general potentials, constructed through a controlling mechanism, can also be obtained applying on a reference state suitable operators. An explicit example is supplied.

  4. Ultrasound-guided approach to the cervical articular process joints in horses: a validation of the technique in cadavers.

    PubMed

    Purefoy Johnson, Jessica; Stack, John David; Rowan, Conor; Handel, Ian; O'Leary, John Mark

    2017-05-22

    To compare accuracy of the ultrasound-guided craniodorsal (CrD) approach with the dorsal (D) approach to the cervical articular process joints, and to evaluate the effect of the transducer, needle gauge, and operator experience. Cervical articular process joints from 14 cadaveric neck specimens were injected using either a D or CrD approach, a linear (13 MHx) or microconvex transducer (10 MHz), and an 18 or 20 gauge needle, by an experienced or inexperienced operator. Injectate consisted of an iodinated contrast material solution. Time taken for injection, number of redirects, and retrieval of synovial fluid were recorded. Accuracy was assessed using a scoring system for contrast seen on computed tomography (CT). The successful performance of intra-articular injections of contrast detected by CT using the D (61/68) and CrD (57/64) approaches was comparable. No significant effect of approach, transducer or needle gauge was observed on injection accuracy, time taken to perform injection, or number of redirects. The 18 gauge needle had a positive correlation with retrieval of synovial fluid. A positive learning curve was observed for the inexperienced operator. Both approaches to the cervical articular process joints were highly accurate. Ultrasound-guided injection of the cervical articular process joints is an easily-learnt technique for an inexperienced veterinarian. Either approach may be employed in the field with a high level of accuracy, using widely available equipment.

  5. Human Error and the International Space Station: Challenges and Triumphs in Science Operations

    NASA Technical Reports Server (NTRS)

    Harris, Samantha S.; Simpson, Beau C.

    2016-01-01

    Any system with a human component is inherently risky. Studies in human factors and psychology have repeatedly shown that human operators will inevitably make errors, regardless of how well they are trained. Onboard the International Space Station (ISS) where crew time is arguably the most valuable resource, errors by the crew or ground operators can be costly to critical science objectives. Operations experts at the ISS Payload Operations Integration Center (POIC), located at NASA's Marshall Space Flight Center in Huntsville, Alabama, have learned that from payload concept development through execution, there are countless opportunities to introduce errors that can potentially result in costly losses of crew time and science. To effectively address this challenge, we must approach the design, testing, and operation processes with two specific goals in mind. First, a systematic approach to error and human centered design methodology should be implemented to minimize opportunities for user error. Second, we must assume that human errors will be made and enable rapid identification and recoverability when they occur. While a systematic approach and human centered development process can go a long way toward eliminating error, the complete exclusion of operator error is not a reasonable expectation. The ISS environment in particular poses challenging conditions, especially for flight controllers and astronauts. Operating a scientific laboratory 250 miles above the Earth is a complicated and dangerous task with high stakes and a steep learning curve. While human error is a reality that may never be fully eliminated, smart implementation of carefully chosen tools and techniques can go a long way toward minimizing risk and increasing the efficiency of NASA's space science operations.

  6. Medical Systems Engineering to Support Mars Mission Crew Autonomy

    NASA Technical Reports Server (NTRS)

    Antonsen, Erik; Mindock, Jennifer

    2017-01-01

    Human spaceflight missions to Mars face exceptionally challenging resource limitations that far exceed those faced before. Increasing transit times, decreasing opportunity for resupply, communications challenges, and extended time to evacuate a crew to definitive medical care dictate a level of crew autonomy in medical care that is beyond the current medical model. To approach this challenge, a medical systems engineering approach is proposed that relies on a clearly articulated Concept of Operations and risk analysis tools that are in development at NASA. This paper proposes an operational clinical model with key terminology and concepts translated to a controls theory paradigm to frame a common language between clinical and engineering teams. This common language will be used for design and validation of an exploration medical system that is fully integrated into a Mars transit vehicle. This approach merges medical simulation, human factors evaluation techniques, and human-in-the-loop testing in ground based analogs to tie medical hardware and software subsystem performance and overall medical system functionality to metrics of operational medical autonomy. Merging increases in operational clinical autonomy with a more restricted vehicle system resource scenario in interplanetary spaceflight will require an unprecedented level of medical and engineering integration. Full integration of medical capabilities into a Mars vehicle system may require a new approach to integrating medical system design and operations into the vehicle Program structure. Prior to the standing-up of a Mars Mission Program, proof of concept is proposed through the Human Research Program.

  7. A bottom-up approach to identifying the maximum operational adaptive capacity of water resource systems to a changing climate

    NASA Astrophysics Data System (ADS)

    Culley, S.; Noble, S.; Yates, A.; Timbs, M.; Westra, S.; Maier, H. R.; Giuliani, M.; Castelletti, A.

    2016-09-01

    Many water resource systems have been designed assuming that the statistical characteristics of future inflows are similar to those of the historical record. This assumption is no longer valid due to large-scale changes in the global climate, potentially causing declines in water resource system performance, or even complete system failure. Upgrading system infrastructure to cope with climate change can require substantial financial outlay, so it might be preferable to optimize existing system performance when possible. This paper builds on decision scaling theory by proposing a bottom-up approach to designing optimal feedback control policies for a water system exposed to a changing climate. This approach not only describes optimal operational policies for a range of potential climatic changes but also enables an assessment of a system's upper limit of its operational adaptive capacity, beyond which upgrades to infrastructure become unavoidable. The approach is illustrated using the Lake Como system in Northern Italy—a regulated system with a complex relationship between climate and system performance. By optimizing system operation under different hydrometeorological states, it is shown that the system can continue to meet its minimum performance requirements for more than three times as many states as it can under current operations. Importantly, a single management policy, no matter how robust, cannot fully utilize existing infrastructure as effectively as an ensemble of flexible management policies that are updated as the climate changes.

  8. No effect of the infiltration of local anaesthetic for total hip arthroplasty using an anterior approach: a randomised placebo controlled trial.

    PubMed

    den Hartog, Y M; Mathijssen, N M C; van Dasselaar, N T; Langendijk, P N J; Vehmeijer, S B W

    2015-06-01

    Only limited data are available regarding the infiltration of local anaesthetic for total hip arthroplasty (THA), and no studies were performed for THA using the anterior approach. In this prospective, randomised placebo-controlled study we investigated the effect of both standard and reverse infiltration of local anaesthetic in combination with the anterior approach for THA. The primary endpoint was the mean numeric rating score for pain four hours post-operatively. In addition, we recorded the length of hospital stay, the operating time, the destination of the patient at discharge, the use of pain medication, the occurrence of side effects and pain scores at various times post-operatively. Between November 2012 and January 2014, 75 patients were included in the study. They were randomised into three groups: standard infiltration of local anaesthetic, reversed infiltration of local anaesthetic, and placebo. There was no difference in mean numeric rating score for pain four hours post-operatively (p = 0.87). There were significantly more side effects at one and eight hours post-operatively in the placebo group (p = 0.02; p = 0.03), but this did not influence the mobilisation of the patients. There were no differences in all other outcomes between the groups. We found no clinically relevant effect when the infiltration of local anaesthetic with ropivacaine and epinephrine was used in a multimodal pain protocol for THA using the anterior approach. ©2015 The British Editorial Society of Bone & Joint Surgery.

  9. Site of potential operating microscope light-induced phototoxicity on the human retina during temporal approach eye surgery.

    PubMed

    Pavilack, M A; Brod, R D

    2001-02-01

    To determine the site of focal illumination on the retina of phakic human cadaver eyes from an operating microscope positioned for temporal approach eye surgery. Experimental study. A Zeiss OPMI-6SFR operating microscope (Zeiss Humphrey Systems, Dublin, CA) was positioned over two phakic human cadaver eyes to measure the site of the focal illumination on the retina by directly observing the illumination on the posterior scleral surface of the globe. External localization of the foveola was made by direct observation using scleral indentation and indirect ophthalmoscopy. Various combinations of microscope angulation and field of view were analyzed. Distance of focal illumination from the operating room microscope relative to the foveola was measured. The diameter of the "hot spot" of focal illumination on the retina was 4.0 mm. With the eye positioned straight ahead and the level operating room microscope positioned for temporal approach eye surgery, the center of retinal illumination was 0.9 and 1.4 mm nasal relative to the foveola when the microscope field of view was centered over the cornea and temporal limbus, respectively. With the microscope angled 5, 10, 15, and 20 degrees temporally (oculars tilted toward surgeon), the center of the illumination was displaced nasal to the foveola by 1.1, 1.5, 3.8, and 5.1 mm, respectively, when the field of view was centered over the cornea and 1.5, 2.6, 4.7, and 6.0 mm, respectively, nasal to the foveola when centered over the temporal limbus. Retinal illumination from an operating microscope positioned for temporal approach eye surgery has the potential for light-induced injury to the fovea. Angulation of the operating microscope by up to 10 degrees temporally when the microscope field of view was centered over the cornea and up to 5 degrees temporally when centered over the temporal limbus was not adequate to displace the focal illumination off the foveola when the eye was in the straight-ahead position. Tilting the operating microscope 15 degrees or more temporally when centered on the pupil and 10 degrees or more when centered over the temporal limbus should safely displace the retinal light exposure away from the fovea during temporal approach surgery. Suggestions for reducing the risk of iatrogenic phototoxicity are reviewed.

  10. Modular space station, phase B extension. Program operations plan

    NASA Technical Reports Server (NTRS)

    1971-01-01

    An organized approach is defined for establishing the most significant requirements pertaining to mission operations, information management, and computer program design and development for the modular space station program. The operations plan pertains to the space station and experiment module program elements and to the ground elements required for mission management and mission support operations.

  11. Systems Engineering Approach and Metrics for Evaluating Network-Centric Operations for U.S. Army Battle Command

    DTIC Science & Technology

    2013-07-01

    Systems Engineering Approach and Metrics for Evaluating Network-Centric Operations for U.S. Army Battle Command by Jock O. Grynovicki and...Battle Command Jock O. Grynovicki and Teresa A. Branscome Human Research and Engineering Directorate, ARL...NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Jock O. Grynovicki and Teresa A. Branscome 5d. PROJECT NUMBER 622716H70 5e. TASK NUMBER

  12. Systemic Operational Design: Epistemological Bumpf or the Way Ahead for Operational Design?

    DTIC Science & Technology

    2006-05-25

    facilitating the design of such architectural frames (meta-concepts), they are doomed to be trapped in a simplistic structuralist approach.”1...systems theory and complexity theory . SOD emerged and evolved in response to inherent challenges in the contemporary Israeli security environment...discussed in subsequent chapters. Theory . Theory is critical to this examination of the CEOD approach and SOD because theory underpins and informs

  13. Sustainable aggregate production planning in the chemical process industry - A benchmark problem and dataset.

    PubMed

    Brandenburg, Marcus; Hahn, Gerd J

    2018-06-01

    Process industries typically involve complex manufacturing operations and thus require adequate decision support for aggregate production planning (APP). The need for powerful and efficient approaches to solve complex APP problems persists. Problem-specific solution approaches are advantageous compared to standardized approaches that are designed to provide basic decision support for a broad range of planning problems but inadequate to optimize under consideration of specific settings. This in turn calls for methods to compare different approaches regarding their computational performance and solution quality. In this paper, we present a benchmarking problem for APP in the chemical process industry. The presented problem focuses on (i) sustainable operations planning involving multiple alternative production modes/routings with specific production-related carbon emission and the social dimension of varying operating rates and (ii) integrated campaign planning with production mix/volume on the operational level. The mutual trade-offs between economic, environmental and social factors can be considered as externalized factors (production-related carbon emission and overtime working hours) as well as internalized ones (resulting costs). We provide data for all problem parameters in addition to a detailed verbal problem statement. We refer to Hahn and Brandenburg [1] for a first numerical analysis based on and for future research perspectives arising from this benchmarking problem.

  14. The Impact of Operative Approach on Postoperative Complications Following Colectomy for Colon Caner.

    PubMed

    Mungo, Benedetto; Papageorge, Christina M; Stem, Miloslawa; Molena, Daniela; Lidor, Anne O

    2017-08-01

    Colectomy is one of the most common major abdominal procedures performed in the USA. A better understanding of risk factors and the effect of operative approach on adverse postoperative outcomes may significantly improve quality of care. Adult patients with a primary diagnosis of colon cancer undergoing colectomy were selected from the National Surgical Quality Improvement Program 2013-2015 targeted colectomy database. Patients were stratified into five groups based on specific operative approach. Univariate and multivariate analyses were used to compare the five groups and identify risk factors for 30-day anastomotic leak, readmission, and mortality. In total, 25,097 patients were included in the study, with a 3.32% anastomotic leak rate, 1.20% mortality rate, and 9.57% readmission rate. After adjusting for other factors, open surgery and conversion to open significantly increased the odds for leak, mortality, and readmission compared to laparoscopy. Additionally, smoking and chemotherapy increased the risk for leak and readmission, while total resection was associated with increased mortality and leak. Operative approach and several other potentially modifiable perioperative factors have a significant impact on risk for adverse postoperative outcomes following colectomy. To improve quality of care for these patients, efforts should be made to identify and minimize the influence of such risk factors.

  15. Nonlinear optics quantum computing with circuit QED.

    PubMed

    Adhikari, Prabin; Hafezi, Mohammad; Taylor, J M

    2013-02-08

    One approach to quantum information processing is to use photons as quantum bits and rely on linear optical elements for most operations. However, some optical nonlinearity is necessary to enable universal quantum computing. Here, we suggest a circuit-QED approach to nonlinear optics quantum computing in the microwave regime, including a deterministic two-photon phase gate. Our specific example uses a hybrid quantum system comprising a LC resonator coupled to a superconducting flux qubit to implement a nonlinear coupling. Compared to the self-Kerr nonlinearity, we find that our approach has improved tolerance to noise in the qubit while maintaining fast operation.

  16. Development of a preprototype hyperfiltration wash water recovery subsystem

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The use of hyperfiltration as a mode of reclamation of waste water on board an extended mission spacecraft was investigated. Two basic approaches are considered with respect to hyperfiltration of wash water recovery. The initial approach involves the use of a hollow fiber permeator and a tubular module, operating at ambient temperature. In this system, relatively large doses of biocides are used to control microbial activity. Since biocides require a long contact time, and many have adverse dematological effects as well as many interact with membrane material, a second approach is considered which involves operating at pasturization temperature.

  17. Building an Economical and Sustainable Lunar Infrastructure to Enable Lunar Industrialization

    NASA Technical Reports Server (NTRS)

    Zuniga, Allison F.; Turner, Mark; Rasky, Daniel; Loucks, Mike; Carrico, John; Policastri, Daniel

    2017-01-01

    A new concept study was initiated to examine the architecture needed to gradually develop an economical, evolvable and sustainable lunar infrastructure using a public/private partnerships approach. This approach would establish partnership agreements between NASA and industry teams to develop a lunar infrastructure system that would be mutually beneficial. This approach would also require NASA and its industry partners to share costs in the development phase and then transfer operation of these infrastructure services back to its industry owners in the execution phase. These infrastructure services may include but are not limited to the following: lunar cargo transportation, power stations, communication towers and satellites, autonomous rover operations, landing pads and resource extraction operations. The public/private partnerships approach used in this study leveraged best practices from NASA's Commercial Orbital Transportation Services (COTS) program which introduced an innovative and economical approach for partnering with industry to develop commercial cargo services to the International Space Station. This program was planned together with the ISS Commercial Resupply Services (CRS) contracts which was responsible for initiating commercial cargo delivery services to the ISS for the first time. The public/private partnerships approach undertaken in the COTS program proved to be very successful in dramatically reducing development costs for these ISS cargo delivery services as well as substantially reducing operational costs. To continue on this successful path towards installing economical infrastructure services for LEO and beyond, this new study, named Lunar COTS (Commercial Operations and Transport Services), was conducted to examine extending the NASA COTS model to cis-lunar space and the lunar surface. The goals of the Lunar COTS concept are to: 1) develop and demonstrate affordable and commercial cis-lunar and surface capabilities, such as lunar cargo delivery and surface power generation, in partnership with industry; 2) incentivize industry to establish economical and sustainable lunar infrastructure services to support NASA missions and initiate lunar commerce; and 3) encourage creation of new space markets for economic growth and benefit. A phased-development approach was also studied to allow for incremental development and demonstration of capabilities needed to build a lunar infrastructure. This paper will describe the Lunar COTS concept goals, objectives and approach for building an economical and sustainable lunar infrastructure. It will also describe the technical challenges and advantages of developing and operating each infrastructure element. It will also describe the potential benefits and progress that can be accomplished in the initial phase of this Lunar COTS approach. Finally, the paper will also look forward to the potential of a robust lunar industrialization environment and its potential effect on the next 50 years of space exploration.

  18. Simulation Evaluation of Synthetic Vision as an Enabling Technology for Equivalent Visual Operations

    NASA Technical Reports Server (NTRS)

    Kramer, Lynda J.; Williams, Steven P.; Bailey, Randall E.

    2008-01-01

    Enhanced Vision (EV) and synthetic vision (SV) systems may serve as enabling technologies to meet the challenges of the Next Generation Air Transportation System (NextGen) Equivalent Visual Operations (EVO) concept ? that is, the ability to achieve or even improve on the safety of Visual Flight Rules (VFR) operations, maintain the operational tempos of VFR, and even, perhaps, retain VFR procedures independent of actual weather and visibility conditions. One significant challenge lies in the definition of required equipage on the aircraft and on the airport to enable the EVO concept objective. A piloted simulation experiment was conducted to evaluate the effects of the presence or absence of Synthetic Vision, the location of this information during an instrument approach (i.e., on a Head-Up or Head-Down Primary Flight Display), and the type of airport lighting information on landing minima. The quantitative data from this experiment were analyzed to begin the definition of performance-based criteria for all-weather approach and landing operations. Objective results from the present study showed that better approach performance was attainable with the head-up display (HUD) compared to the head-down display (HDD). A slight performance improvement in HDD performance was shown when SV was added, as the pilots descended below 200 ft to a 100 ft decision altitude, but this performance was not tested for statistical significance (nor was it expected to be statistically significant). The touchdown data showed that regardless of the display concept flown (SV HUD, Baseline HUD, SV HDD, Baseline HDD) a majority of the runs were within the performance-based defined approach and landing criteria in all the visibility levels, approach lighting systems, and decision altitudes tested. For this visual flight maneuver, RVR appeared to be the most significant influence in touchdown performance. The approach lighting system clearly impacted the pilot's ability to descend to 100 ft height above touchdown based on existing Federal Aviation Regulation (FAR) 91.175 using a 200 ft decision height, but did not appear to influence touchdown performance or approach path maintenance

  19. Large desmoid-type fibromatosis of the shoulder girdle: operative approach selection and clinic outcome.

    PubMed

    Tang, Fan; Min, Li; Yin, Rui; Zhang, Wenli; Zhou, Yong; Luo, Yi; Shi, Rui; Duan, Hong; Tu, Chongqi

    2015-02-01

    Surgical resection of large desmoid-type fibromatosis (DTF) of the shoulder girdle is challenging. This article discusses the operative approach and evaluates the clinic outcome. Twenty-one cases between June 2003 and June 2012 were retrospectively reviewed. Eleven patients newly diagnosed and ten had previous operations. Mean tumour size was 10.5 cm (range, 7.0-19.0 cm). We divided the shoulder girdle into four regions; the adopted surgical resection was en bloc in 18 cases and piecemeal resection in three. In nine cases we took an anterior approach, ten a posterior approach and two a combined anteroposterior (AP) approach. Brachytherapy with permanent I(125) implantation was applied in all cases. All 21 patients were followed up for a mean of 49.8 (range, 18-136) months. Recurrence was seen in two patients, with the overall recurrence rate of 9.5 %. The Musculoskeletal Tumour Score (MSTS) was between 56.7 and 96.7 %, with the average at 78.9 % and excellent-good rate 95.2 %. Complications were found in three of the 21 patients (14.3 %). Surgical resection with the precondition of preserving vital structure for large DTF of the shoulder girdle is necessary. According to our new partition, it was suitable to take an anterior approach when regions I or I + II were involved, posterior approach for regions II, III or II + III; combined AP approach when involving region I + II + III; and anterior or posterior approach for region IV, depending upon tumour location.

  20. Comparison of clinical efficacy and safety among three surgical approaches for the treatment of spinal tuberculosis: a meta-analysis.

    PubMed

    Yang, Pinglin; Zang, Quanjin; Kang, Jian; Li, Haopeng; He, Xijing

    2016-12-01

    We aimed to provide evidence for clinical choice of surgical approach in treating spinal tuberculosis, including anterior, posterior and combined approaches (combined anterior and posterior approach). A literature search up to June 2015 was performed on PubMed, Embase, Cochrane library, CNKI, Wanfang and Weipu database. Weighted mean differences (WMDs) or risk radios (RRs) and their 95 % confidence intervals (CI) were calculated. Total 26 studies with 2345 spinal tuberculosis adults were analyzed. Results showed advantages of posterior approach compared with anterior approach in operation time (WMD = 20.91; 95 % CI: 9.05-32.76), blood loss (WMD = 72.32, 95 % CI: 13.87-130.78), correction of angle (WMD = -2.47; 95 % CI: -4.04 to -0.90) and complications (RR = 1.78; 95 % CI: 1.21-2.60), and compared with combined approach in operation time (WMD = -82.76; 95 % CI: -94.38 to -71.14), blood loss (WMD = -263.63; 95 % CI: -336.85 to -190.41), hospital stay [(WMD = -4.60; 95 % CI: -5.10 to -4.10) and complications (RR = 0.36; 95 % CI: 0.23-0.58]. Meanwhile, significantly larger correction of angle (WMD = -2.25; 95 % CI: -4.35 to -0.14; P = 0.04) and less loss of correction (WMD = 3.97; 95 % CI: 2.22-5.72) were found when compared combined approach with anterior approach. However, combined approach had significantly longer operation time (WMD = -41.92; 95 % CI: -52.45 to -31.38) and more blood loss (WMD = -102.18; 95 % CI: -160.45 to -43.91) than anterior approach. Posterior approach has better clinical outcomes than anterior or combined approach for spinal tuberculosis. However, individual assessment of each case should be considered in the clinical application of these surgical approaches.

  1. Viking Mars encounter

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Various phases of planetary operations related to the Viking mission to Mars are described. Topics discussed include: approach phase, Mars orbit insertion, prelanding orbital activities, separation, descent and landing, surface operations, surface sampling and operations starting, orbiter science and radio science, Viking 2, Deep Space Network and data handling.

  2. Some Recurrent Disagreements about Social Change Which Affect Action Research Projects.

    ERIC Educational Resources Information Center

    Hofstetter, Heather N.; Hofstetter, Merlin I.

    This paper describes the beliefs and values of a pluralistic approach to social change and of four competing approaches: social Darwinism, functionalism, militancy, and conflict theory. Stressing the alienation and dogmatism of the competing approaches, the authors relate each approach to its operation in community action projects. Social…

  3. 49 CFR 236.803 - Signal, approach.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Signal, approach. 236.803 Section 236.803..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.803 Signal, approach. A roadway signal used to govern the approach to another signal and if operative so...

  4. 49 CFR 236.803 - Signal, approach.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Signal, approach. 236.803 Section 236.803..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.803 Signal, approach. A roadway signal used to govern the approach to another signal and if operative so...

  5. 49 CFR 236.803 - Signal, approach.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Signal, approach. 236.803 Section 236.803..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.803 Signal, approach. A roadway signal used to govern the approach to another signal and if operative so...

  6. 49 CFR 236.803 - Signal, approach.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Signal, approach. 236.803 Section 236.803..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.803 Signal, approach. A roadway signal used to govern the approach to another signal and if operative so...

  7. 49 CFR 236.803 - Signal, approach.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Signal, approach. 236.803 Section 236.803..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.803 Signal, approach. A roadway signal used to govern the approach to another signal and if operative so...

  8. Ankle arthrodesis: A systematic approach and review of the literature

    PubMed Central

    Yasui, Youichi; Hannon, Charles P; Seow, Dexter; Kennedy, John G

    2016-01-01

    Ankle arthrodesis is a common treatment used for patients with end-stage ankle arthritis (ESAA). The surgical goal of ankle arthrodesis is to obtain bony union between the tibia and talus with adequate alignment [slight valgus (0°-5°)], neutral dorsiflexion, and slight external rotation positions) in order to provide a pain-free plantigrade foot for weightbearing activities. There are many variations in operative technique including deferring approaches (open or arthroscopic) and differing fixation methods (internal or external fixation). Each technique has its advantage and disadvantages. Success of ankle arthrodesis can be dependent on several factors, including patient selection, surgeons’ skills, patient comorbidities, operative care, etc. However, from our experience, the majority of ESAA patients obtain successful clinical outcomes. This review aims to outline the indications and goals of arthrodesis for treatment of ESAA and discuss both open and arthroscopic ankle arthrodesis. A systematic step by step operative technique guide is presented for both the arthroscopic and open approaches including a postoperative protocol. We review the current evidence supporting each approach. The review finishes with a report of the most recent evidence of outcomes after both approaches and concerns regarding the development of hindfoot arthritis. PMID:27900266

  9. Assessing Dual Sensor Enhanced Flight Vision Systems to Enable Equivalent Visual Operations

    NASA Technical Reports Server (NTRS)

    Kramer, Lynda J.; Etherington, Timothy J.; Severance, Kurt; Bailey, Randall E.; Williams, Steven P.; Harrison, Stephanie J.

    2016-01-01

    Flight deck-based vision system technologies, such as Synthetic Vision (SV) and Enhanced Flight Vision Systems (EFVS), may serve as a revolutionary crew/vehicle interface enabling technologies to meet the challenges of the Next Generation Air Transportation System Equivalent Visual Operations (EVO) concept - that is, the ability to achieve the safety of current-day Visual Flight Rules (VFR) operations and maintain the operational tempos of VFR irrespective of the weather and visibility conditions. One significant challenge lies in the definition of required equipage on the aircraft and on the airport to enable the EVO concept objective. A motion-base simulator experiment was conducted to evaluate the operational feasibility, pilot workload and pilot acceptability of conducting straight-in instrument approaches with published vertical guidance to landing, touchdown, and rollout to a safe taxi speed in visibility as low as 300 ft runway visual range by use of onboard vision system technologies on a Head-Up Display (HUD) without need or reliance on natural vision. Twelve crews evaluated two methods of combining dual sensor (millimeter wave radar and forward looking infrared) EFVS imagery on pilot-flying and pilot-monitoring HUDs as they made approaches to runways with and without touchdown zone and centerline lights. In addition, the impact of adding SV to the dual sensor EFVS imagery on crew flight performance, workload, and situation awareness during extremely low visibility approach and landing operations was assessed. Results indicate that all EFVS concepts flown resulted in excellent approach path tracking and touchdown performance without any workload penalty. Adding SV imagery to EFVS concepts provided situation awareness improvements but no discernible improvements in flight path maintenance.

  10. Dynamic Blowout Risk Analysis Using Loss Functions.

    PubMed

    Abimbola, Majeed; Khan, Faisal

    2018-02-01

    Most risk analysis approaches are static; failing to capture evolving conditions. Blowout, the most feared accident during a drilling operation, is a complex and dynamic event. The traditional risk analysis methods are useful in the early design stage of drilling operation while falling short during evolving operational decision making. A new dynamic risk analysis approach is presented to capture evolving situations through dynamic probability and consequence models. The dynamic consequence models, the focus of this study, are developed in terms of loss functions. These models are subsequently integrated with the probability to estimate operational risk, providing a real-time risk analysis. The real-time evolving situation is considered dependent on the changing bottom-hole pressure as drilling progresses. The application of the methodology and models are demonstrated with a case study of an offshore drilling operation evolving to a blowout. © 2017 Society for Risk Analysis.

  11. A Sensemaking Perspective on Situation Awareness in Power Grid Operations

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

    Greitzer, Frank L.; Schur, Anne; Paget, Mia L.

    2008-07-21

    With increasing complexity and interconnectivity of the electric power grid, the scope and complexity of grid operations continues to grow. New paradigms are needed to guide research to improve operations by enhancing situation awareness of operators. Research on human factors/situation awareness is described within a taxonomy of tools and approaches that address different levels of cognitive processing. While user interface features and visualization approaches represent the predominant focus of human factors studies of situation awareness, this paper argues that a complementary level, sensemaking, deserves further consideration by designers of decision support systems for power grid operations. A sensemaking perspective onmore » situation aware-ness may reveal new insights that complement ongoing human factors research, where the focus of the investigation of errors is to understand why the decision makers experienced the situation the way they did, or why what they saw made sense to them at the time.« less

  12. MODAL TRACKING of A Structural Device: A Subspace Identification Approach

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

    Candy, J. V.; Franco, S. N.; Ruggiero, E. L.

    Mechanical devices operating in an environment contaminated by noise, uncertainties, and extraneous disturbances lead to low signal-to-noise-ratios creating an extremely challenging processing problem. To detect/classify a device subsystem from noisy data, it is necessary to identify unique signatures or particular features. An obvious feature would be resonant (modal) frequencies emitted during its normal operation. In this report, we discuss a model-based approach to incorporate these physical features into a dynamic structure that can be used for such an identification. The approach we take after pre-processing the raw vibration data and removing any extraneous disturbances is to obtain a representation ofmore » the structurally unknown device along with its subsystems that capture these salient features. One approach is to recognize that unique modal frequencies (sinusoidal lines) appear in the estimated power spectrum that are solely characteristic of the device under investigation. Therefore, the objective of this effort is based on constructing a black box model of the device that captures these physical features that can be exploited to “diagnose” whether or not the particular device subsystem (track/detect/classify) is operating normally from noisy vibrational data. Here we discuss the application of a modern system identification approach based on stochastic subspace realization techniques capable of both (1) identifying the underlying black-box structure thereby enabling the extraction of structural modes that can be used for analysis and modal tracking as well as (2) indicators of condition and possible changes from normal operation.« less

  13. SATS HVO Concept Validation Experiment

    NASA Technical Reports Server (NTRS)

    Consiglio, Maria; Williams, Daniel; Murdoch, Jennifer; Adams, Catherine

    2005-01-01

    A human-in-the-loop simulation experiment was conducted at the NASA Langley Research Center s (LaRC) Air Traffic Operations Lab (ATOL) in an effort to comprehensively validate tools and procedures intended to enable the Small Aircraft Transportation System, Higher Volume Operations (SATS HVO) concept of operations. The SATS HVO procedures were developed to increase the rate of operations at non-towered, non-radar airports in near all-weather conditions. A key element of the design is the establishment of a volume of airspace around designated airports where pilots accept responsibility for self-separation. Flights operating at these airports, are given approach sequencing information computed by a ground based automated system. The SATS HVO validation experiment was conducted in the ATOL during the spring of 2004 in order to determine if a pilot can safely and proficiently fly an airplane while performing SATS HVO procedures. Comparative measures of flight path error, perceived workload and situation awareness were obtained for two types of scenarios. Baseline scenarios were representative of today s system utilizing procedure separation, where air traffic control grants one approach or departure clearance at a time. SATS HVO scenarios represented approaches and departure procedures as described in the SATS HVO concept of operations. Results from the experiment indicate that low time pilots were able to fly SATS HVO procedures and maintain self-separation as safely and proficiently as flying today's procedures.

  14. Can We Practically Bring Physics-based Modeling Into Operational Analytics Tools?

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

    Granderson, Jessica; Bonvini, Marco; Piette, Mary Ann

    We present that analytics software is increasingly used to improve and maintain operational efficiency in commercial buildings. Energy managers, owners, and operators are using a diversity of commercial offerings often referred to as Energy Information Systems, Fault Detection and Diagnostic (FDD) systems, or more broadly Energy Management and Information Systems, to cost-effectively enable savings on the order of ten to twenty percent. Most of these systems use data from meters and sensors, with rule-based and/or data-driven models to characterize system and building behavior. In contrast, physics-based modeling uses first-principles and engineering models (e.g., efficiency curves) to characterize system and buildingmore » behavior. Historically, these physics-based approaches have been used in the design phase of the building life cycle or in retrofit analyses. Researchers have begun exploring the benefits of integrating physics-based models with operational data analytics tools, bridging the gap between design and operations. In this paper, we detail the development and operator use of a software tool that uses hybrid data-driven and physics-based approaches to cooling plant FDD and optimization. Specifically, we describe the system architecture, models, and FDD and optimization algorithms; advantages and disadvantages with respect to purely data-driven approaches; and practical implications for scaling and replicating these techniques. Finally, we conclude with an evaluation of the future potential for such tools and future research opportunities.« less

  15. An integrated approach to patient-specific predictive modeling for single ventricle heart palliation.

    PubMed

    Corsini, Chiara; Baker, Catriona; Kung, Ethan; Schievano, Silvia; Arbia, Gregory; Baretta, Alessia; Biglino, Giovanni; Migliavacca, Francesco; Dubini, Gabriele; Pennati, Giancarlo; Marsden, Alison; Vignon-Clementel, Irene; Taylor, Andrew; Hsia, Tain-Yen; Dorfman, Adam

    2014-01-01

    In patients with congenital heart disease and a single ventricle (SV), ventricular support of the circulation is inadequate, and staged palliative surgery (usually 3 stages) is needed for treatment. In the various palliative surgical stages individual differences in the circulation are important and patient-specific surgical planning is ideal. In this study, an integrated approach between clinicians and engineers has been developed, based on patient-specific multi-scale models, and is here applied to predict stage 2 surgical outcomes. This approach involves four distinct steps: (1) collection of pre-operative clinical data from a patient presenting for SV palliation, (2) construction of the pre-operative model, (3) creation of feasible virtual surgical options which couple a three-dimensional model of the surgical anatomy with a lumped parameter model (LPM) of the remainder of the circulation and (4) performance of post-operative simulations to aid clinical decision making. The pre-operative model is described, agreeing well with clinical flow tracings and mean pressures. Two surgical options (bi-directional Glenn and hemi-Fontan operations) are virtually performed and coupled to the pre-operative LPM, with the hemodynamics of both options reported. Results are validated against postoperative clinical data. Ultimately, this work represents the first patient-specific predictive modeling of stage 2 palliation using virtual surgery and closed-loop multi-scale modeling.

  16. Continuous hesitant fuzzy aggregation operators and their application to decision making under interval-valued hesitant fuzzy setting.

    PubMed

    Peng, Ding-Hong; Wang, Tie-Dan; Gao, Chang-Yuan; Wang, Hua

    2014-01-01

    Interval-valued hesitant fuzzy set (IVHFS), which is the further generalization of hesitant fuzzy set, can overcome the barrier that the precise membership degrees are sometimes hard to be specified and permit the membership degrees of an element to a set to have a few different interval values. To efficiently and effectively aggregate the interval-valued hesitant fuzzy information, in this paper, we investigate the continuous hesitant fuzzy aggregation operators with the aid of continuous OWA operator; the C-HFOWA operator and C-HFOWG operator are presented and their essential properties are studied in detail. Then, we extend the C-HFOW operators to aggregate multiple interval-valued hesitant fuzzy elements and then develop the weighted C-HFOW (WC-HFOWA and WC-HFOWG) operators, the ordered weighted C-HFOW (OWC-HFOWA and OWC-HFOWG) operators, and the synergetic weighted C-HFOWA (SWC-HFOWA and SWC-HFOWG) operators; some properties are also discussed to support them. Furthermore, a SWC-HFOW operators-based approach for multicriteria decision making problem is developed. Finally, a practical example involving the evaluation of service quality of high-tech enterprises is carried out and some comparative analyses are performed to demonstrate the applicability and effectiveness of the developed approaches.

  17. Continuous Hesitant Fuzzy Aggregation Operators and Their Application to Decision Making under Interval-Valued Hesitant Fuzzy Setting

    PubMed Central

    Wang, Tie-Dan; Gao, Chang-Yuan; Wang, Hua

    2014-01-01

    Interval-valued hesitant fuzzy set (IVHFS), which is the further generalization of hesitant fuzzy set, can overcome the barrier that the precise membership degrees are sometimes hard to be specified and permit the membership degrees of an element to a set to have a few different interval values. To efficiently and effectively aggregate the interval-valued hesitant fuzzy information, in this paper, we investigate the continuous hesitant fuzzy aggregation operators with the aid of continuous OWA operator; the C-HFOWA operator and C-HFOWG operator are presented and their essential properties are studied in detail. Then, we extend the C-HFOW operators to aggregate multiple interval-valued hesitant fuzzy elements and then develop the weighted C-HFOW (WC-HFOWA and WC-HFOWG) operators, the ordered weighted C-HFOW (OWC-HFOWA and OWC-HFOWG) operators, and the synergetic weighted C-HFOWA (SWC-HFOWA and SWC-HFOWG) operators; some properties are also discussed to support them. Furthermore, a SWC-HFOW operators-based approach for multicriteria decision making problem is developed. Finally, a practical example involving the evaluation of service quality of high-tech enterprises is carried out and some comparative analyses are performed to demonstrate the applicability and effectiveness of the developed approaches. PMID:24987747

  18. An Evidenced-Based Approach for Estimating Decompression Sickness Risk in Aircraft Operations

    NASA Technical Reports Server (NTRS)

    Robinson, Ronald R.; Dervay, Joseph P.; Conkin, Johnny

    1999-01-01

    Estimating the risk of decompression Sickness (DCS) in aircraft operations remains a challenge, making the reduction of this risk through the development of operationally acceptable denitrogenation schedules difficult. In addition, the medical recommendations which are promulgated are often not supported by rigorous evaluation of the available data, but are instead arrived at by negotiation with the aircraft operations community, are adapted from other similar aircraft operations, or are based upon the opinion of the local medical community. We present a systematic approach for defining DCS risk in aircraft operations by analyzing the data available for a specific aircraft, flight profile, and aviator population. Once the risk of DCS in a particular aircraft operation is known, appropriate steps can be taken to reduce this risk to a level acceptable to the applicable aviation community. Using this technique will allow any aviation medical community to arrive at the best estimate of DCS risk for its specific mission and aviator population and will allow systematic reevaluation of the decisions regarding DCS risk reduction when additional data are available.

  19. 14 CFR 65.37 - Skill requirements: Operating positions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., prescribed instrument approach, and departure procedures. (9) Radar alignment and technical operation. (10) The application of the prescribed radar and nonradar separation standard, as appropriate. [Doc. No...

  20. 14 CFR 65.37 - Skill requirements: Operating positions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., prescribed instrument approach, and departure procedures. (9) Radar alignment and technical operation. (10) The application of the prescribed radar and nonradar separation standard, as appropriate. [Doc. No...

  1. 14 CFR 65.37 - Skill requirements: Operating positions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., prescribed instrument approach, and departure procedures. (9) Radar alignment and technical operation. (10) The application of the prescribed radar and nonradar separation standard, as appropriate. [Doc. No...

  2. 14 CFR 65.37 - Skill requirements: Operating positions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., prescribed instrument approach, and departure procedures. (9) Radar alignment and technical operation. (10) The application of the prescribed radar and nonradar separation standard, as appropriate. [Doc. No...

  3. 14 CFR 65.37 - Skill requirements: Operating positions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., prescribed instrument approach, and departure procedures. (9) Radar alignment and technical operation. (10) The application of the prescribed radar and nonradar separation standard, as appropriate. [Doc. No...

  4. Comparison of the feasibility and effectiveness of transradial coronary angiography via right versus left radial artery approaches (from the PREVAIL Study).

    PubMed

    Pelliccia, Francesco; Trani, Carlo; Biondi-Zoccai, Giuseppe G L; Nazzaro, Marco; Berni, Andrea; Patti, Giuseppe; Patrizi, Roberto; Pironi, Bruno; Mazzarotto, Pietro; Gioffrè, Gaetano; Speciale, Giulio; Pristipino, Christian

    2012-09-15

    It remains undefined if transradial coronary angiography from a right or left radial arterial approach differs in real-world practice. To address this issue, we performed a subanalysis of the PREVAIL study. The PREVAIL study was a prospective, multicenter, observational survey of unselected consecutive patients undergoing invasive cardiovascular procedures over a 1-month observation period, specifically aimed at assessing the outcomes of radial approach in the contemporary real world. The choice of arterial approach was left to the discretion of the operator. Prespecified end points of this subanalysis were procedural characteristics. Of 1,052 patients consecutively enrolled, 509 patients underwent transradial catheterization, 304 with a right radial and 205 with a left radial approach. Procedural success rates were similar between the 2 groups. Compared to the left radial group, the right radial group had longer procedure duration (46 ± 29 vs 33 ± 24 minutes, p <0.0001) and fluoroscopy time (765 ± 787 vs 533 ± 502, p <0.0001). At multivariate analysis, including a parsimonious propensity score for the choice of left radial approach, duration of procedure (beta coefficient 11.38, p <0.001) and total dose-area product (beta coefficient 11.38, p <0.001) were independently associated with the choice of the left radial artery approach. The operator's proficiency in right/left radial approach did not influence study results. In conclusion, right and left radial approaches are feasible and effective to perform percutaneous procedures. In the contemporary real world, however, the left radial route is associated with shorter procedures and lower radiologic exposure than the right radial approach, independently of an operator's proficiency. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Human-Interaction Challenges in UAV-Based Autonomous Surveillance

    NASA Technical Reports Server (NTRS)

    Freed, Michael; Harris, Robert; Shafto, Michael G.

    2004-01-01

    Autonomous UAVs provide a platform for intelligent surveillance in application domains ranging from security and military operations to scientific information gathering and land management. Surveillance tasks are often long duration, requiring that any approach be adaptive to changes in the environment or user needs. We describe a decision- theoretic model of surveillance, appropriate for use on our autonomous helicopter, that provides a basis for optimizing the value of information returned by the UAV. From this approach arise a range of challenges in making this framework practical for use by human operators lacking specialized knowledge of autonomy and mathematics. This paper describes our platform and approach, then describes human-interaction challenges arising from this approach that we have identified and begun to address.

  6. Fatigue Factors in Regional Airline Operations

    NASA Technical Reports Server (NTRS)

    Rosekind, Mark R.; Weldon, Keri J.; Co, Elizabeth L.; Miller, Donna L.; Gregory, Kevin B.; Smith, Roy M.; Johnson, Julie M.; Gander, Philippa H.; Lebacqz, J. Victor

    1994-01-01

    This paper describes human sleep and circadian physiology regarding their role as contributors to fatigue engendered by flight operations. The demands of regional airline operations are then examined for potential areas where these physiological factors will be affected. Finally, approaches to systematically investigate these issues scientifically will be described.

  7. 32 CFR 260.3 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... operations. Direct competition. The presence and operation of a DoD Component vending machine or a vending... machines or vending facilities operated in areas serving employees, the majority of whom normally do not have access (in terms of uninterrupted ease of approach and the amount of time required to patronize...

  8. 32 CFR 260.3 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... operations. Direct competition. The presence and operation of a DoD Component vending machine or a vending... machines or vending facilities operated in areas serving employees, the majority of whom normally do not have access (in terms of uninterrupted ease of approach and the amount of time required to patronize...

  9. 32 CFR 260.3 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... operations. Direct competition. The presence and operation of a DoD Component vending machine or a vending... machines or vending facilities operated in areas serving employees, the majority of whom normally do not have access (in terms of uninterrupted ease of approach and the amount of time required to patronize...

  10. Domain Adaption of Parsing for Operative Notes

    PubMed Central

    Wang, Yan; Pakhomov, Serguei; Ryan, James O.; Melton, Genevieve B.

    2016-01-01

    Background Full syntactic parsing of clinical text as a part of clinical natural language processing (NLP) is critical for a wide range of applications, such as identification of adverse drug reactions, patient cohort identification, and gene interaction extraction. Several robust syntactic parsers are publicly available to produce linguistic representations for sentences. However, these existing parsers are mostly trained on general English text and often require adaptation for optimal performance on clinical text. Our objective was to adapt an existing general English parser for the clinical text of operative reports via lexicon augmentation, statistics adjusting, and grammar rules modification based on a set of biomedical text. Method The Stanford unlexicalized probabilistic context-free grammar (PCFG) parser lexicon was expanded with SPECIALIST lexicon along with statistics collected from a limited set of operative notes tagged with a two of POS taggers (GENIA tagger and MedPost). The most frequently occurring verb entries of the SPECIALIST lexicon were adjusted based on manual review of verb usage in operative notes. Stanford parser grammar production rules were also modified based on linguistic features of operative reports. An analogous approach was then applied to the GENIA corpus to test the generalizability of this approach to biomedical text. Results The new unlexicalized PCFG parser extended with the extra lexicon from SPECIALIST along with accurate statistics collected from an operative note corpus tagged with GENIA POS tagger improved the parser performance by 2.26% from 87.64% to 89.90%. There was a progressive improvement with the addition of multiple approaches. Most of the improvement occurred with lexicon augmentation combined with statistics from the operative notes corpus. Application of this approach on the GENIA corpus showed that parsing performance was boosted by 3.81% with a simple new grammar and the addition of the GENIA corpus lexicon. Conclusion Using statistics collected from clinical text tagged with POS taggers along with proper modification of grammars and lexicons of an unlexicalized PCFG parser can improve parsing performance. PMID:25661593

  11. Nonoperative management for major blunt hepatic trauma. A case report.

    PubMed

    Mingoli, Andrea; Saracino, Andrea; Brachini, Gioia; Mariotta, Giovanni; Migliori, Emanuele; Silvestri, Vania

    2015-03-16

    Over the past 20 years the management of blunt liver trauma has evolved from a primary operative approach to a nonoperative one, for both low and high grade injuries, only on the basis of hemodynamic stability. However, in spite of a high success rate of non operative management, it is frequently observed, also in our country, an old fashioned way to approach these patients, based on habit more than observation and evidence based medicine. We present a case of successful nonoperative treatment of a grade IV blunt liver trauma (lacero-contusive injury of V, VI and VII segments) in a 34-year-old woman. Nowadays more than 85% of liver injuries are managed without operative intervention, irrespective of the injury grade. Success rate of the conservative approach ranges from 82% to 100% and almost all complications (14% in high grade injuries) can be managed with interventional radiology procedures, still avoiding major surgery. Today, in the absence of other abdominal injuries requiring surgical exploration, hemodynamic instability from ongoing hemorrhage after primary evaluation and resuscitative treatment, is the only indication to an operative management of traumatic liver injuries.

  12. On the preventive management of sediment-related sewer blockages: a combined maintenance and routing optimization approach.

    PubMed

    Fontecha, John E; Akhavan-Tabatabaei, Raha; Duque, Daniel; Medaglia, Andrés L; Torres, María N; Rodríguez, Juan Pablo

    In this work we tackle the problem of planning and scheduling preventive maintenance (PM) of sediment-related sewer blockages in a set of geographically distributed sites that are subject to non-deterministic failures. To solve the problem, we extend a combined maintenance and routing (CMR) optimization approach which is a procedure based on two components: (a) first a maintenance model is used to determine the optimal time to perform PM operations for each site and second (b) a mixed integer program-based split procedure is proposed to route a set of crews (e.g., sewer cleaners, vehicles equipped with winches or rods and dump trucks) in order to perform PM operations at a near-optimal minimum expected cost. We applied the proposed CMR optimization approach to two (out of five) operative zones in the city of Bogotá (Colombia), where more than 100 maintenance operations per zone must be scheduled on a weekly basis. Comparing the CMR against the current maintenance plan, we obtained more than 50% of cost savings in 90% of the sites.

  13. Real-time solution of linear computational problems using databases of parametric reduced-order models with arbitrary underlying meshes

    NASA Astrophysics Data System (ADS)

    Amsallem, David; Tezaur, Radek; Farhat, Charbel

    2016-12-01

    A comprehensive approach for real-time computations using a database of parametric, linear, projection-based reduced-order models (ROMs) based on arbitrary underlying meshes is proposed. In the offline phase of this approach, the parameter space is sampled and linear ROMs defined by linear reduced operators are pre-computed at the sampled parameter points and stored. Then, these operators and associated ROMs are transformed into counterparts that satisfy a certain notion of consistency. In the online phase of this approach, a linear ROM is constructed in real-time at a queried but unsampled parameter point by interpolating the pre-computed linear reduced operators on matrix manifolds and therefore computing an interpolated linear ROM. The proposed overall model reduction framework is illustrated with two applications: a parametric inverse acoustic scattering problem associated with a mockup submarine, and a parametric flutter prediction problem associated with a wing-tank system. The second application is implemented on a mobile device, illustrating the capability of the proposed computational framework to operate in real-time.

  14. Time-of-flight-assisted Kinect camera-based people detection for intuitive human robot cooperation in the surgical operating room.

    PubMed

    Beyl, Tim; Nicolai, Philip; Comparetti, Mirko D; Raczkowsky, Jörg; De Momi, Elena; Wörn, Heinz

    2016-07-01

    Scene supervision is a major tool to make medical robots safer and more intuitive. The paper shows an approach to efficiently use 3D cameras within the surgical operating room to enable for safe human robot interaction and action perception. Additionally the presented approach aims to make 3D camera-based scene supervision more reliable and accurate. A camera system composed of multiple Kinect and time-of-flight cameras has been designed, implemented and calibrated. Calibration and object detection as well as people tracking methods have been designed and evaluated. The camera system shows a good registration accuracy of 0.05 m. The tracking of humans is reliable and accurate and has been evaluated in an experimental setup using operating clothing. The robot detection shows an error of around 0.04 m. The robustness and accuracy of the approach allow for an integration into modern operating room. The data output can be used directly for situation and workflow detection as well as collision avoidance.

  15. Stable, high-order computation of impedance-impedance operators for three-dimensional layered medium simulations.

    PubMed

    Nicholls, David P

    2018-04-01

    The faithful modelling of the propagation of linear waves in a layered, periodic structure is of paramount importance in many branches of the applied sciences. In this paper, we present a novel numerical algorithm for the simulation of such problems which is free of the artificial singularities present in related approaches. We advocate for a surface integral formulation which is phrased in terms of impedance-impedance operators that are immune to the Dirichlet eigenvalues which plague the Dirichlet-Neumann operators that appear in classical formulations. We demonstrate a high-order spectral algorithm to simulate these latter operators based upon a high-order perturbation of surfaces methodology which is rapid, robust and highly accurate. We demonstrate the validity and utility of our approach with a sequence of numerical simulations.

  16. The Operator Guide: An Ambient Persuasive Interface in the Factory

    NASA Astrophysics Data System (ADS)

    Meschtscherjakov, Alexander; Reitberger, Wolfgang; Pöhr, Florian; Tscheligi, Manfred

    In this paper we introduce the context of a semiconductor factory as a promising area for the application of innovative interaction approaches. In order to increase efficiency ambient persuasive interfaces, which influence the operators' behaviour to perform in an optimized way, could constitute a potential strategy. We present insights gained from qualitative studies conducted in a specific semiconductor factory and provide a description of typical work processes and already deployed interfaces in this context. These findings informed the design of a prototype of an ambient persuasive interface within this realm - the "Operator Guide". Its overall aim is to improve work efficiency, while still maintaining a minimal error rate. We provide a detailed description of the Operator Guide along with an outlook of the next steps within a user-centered design approach.

  17. Stable, high-order computation of impedance-impedance operators for three-dimensional layered medium simulations

    NASA Astrophysics Data System (ADS)

    Nicholls, David P.

    2018-04-01

    The faithful modelling of the propagation of linear waves in a layered, periodic structure is of paramount importance in many branches of the applied sciences. In this paper, we present a novel numerical algorithm for the simulation of such problems which is free of the artificial singularities present in related approaches. We advocate for a surface integral formulation which is phrased in terms of impedance-impedance operators that are immune to the Dirichlet eigenvalues which plague the Dirichlet-Neumann operators that appear in classical formulations. We demonstrate a high-order spectral algorithm to simulate these latter operators based upon a high-order perturbation of surfaces methodology which is rapid, robust and highly accurate. We demonstrate the validity and utility of our approach with a sequence of numerical simulations.

  18. [New anterolateral approach of distal femur for treatment of distal femoral fractures].

    PubMed

    Zhang, Bin; Dai, Min; Zou, Fan; Luo, Song; Li, Binhua; Qiu, Ping; Nie, Tao

    2013-11-01

    To assess the effectiveness of the new anterolateral approach of the distal femur for the treatment of distal femoral fractures. Between July 2007 and December 2009, 58 patients with distal femoral fractures were treated by new anterolateral approach of the distal femur in 28 patients (new approach group) and by conventional approach in 30 patients (conventional approach group). There was no significant difference in gender, age, cause of injury, affected side, type of fracture, disease duration, complication, or preoperative intervention (P > 0.05). The operation time, intraoperative blood loss, intraoperative fluoroscopy frequency, hospitalization days, and Hospital for Special Surgery (HSS) score of knee were recorded. Operation was successfully completed in all patients of 2 groups, and healing of incision by first intention was obtained; no vascular and nerves injuries occurred. The operation time and intraoperative fluoroscopy frequency of new approach group were significantly less than those of conventional approach group (P < 0.05). But the intraoperative blood loss and the hospitalization days showed no significant difference between 2 groups (P > 0.05). All patients were followed up 12-36 months (mean, 19.8 months). Bone union was shown on X-ray films; the fracture healing time was (12.62 +/- 2.34) weeks in the new approach group and was (13.78 +/- 1.94) weeks in the conventional approach group, showing no significant difference (t=2.78, P=0.10). The knee HSS score at last follow-up was 94.4 +/- 4.2 in the new approach group, and was 89.2 +/- 6.0 in the conventional approach group, showing significant difference between 2 groups (t=3.85, P=0.00). New anterolateral approach of the distal femur for distal femoral fractures has the advantages of exposure plenitude, minimal tissue trauma, and early function rehabilitation training so as to enhance the function recovery of knee joint.

  19. Transitioning to the direct anterior approach in total hip arthroplasty. Is it a true muscle sparing approach when performed by a low volume hip replacement surgeon?

    PubMed

    Nistor, Dan-Viorel; Caterev, Sergiu; Bolboacă, Sorana-Daniela; Cosma, Dan; Lucaciu, Dan Osvald Gheorghe; Todor, Adrian

    2017-11-01

    We conducted this study to establish if the transition from a lateral approach (LA) to the direct anterior approach (DAA) for a low volume hip arthroplasty surgeon during the steep learning curve can be performed maintaining the muscle sparing approach of the DAA without increasing the complication rates. In this controlled, prospective, randomized clinical study we investigated 70 patients (35 DAA, 35 LA) with similar demographics that underwent a total hip arthroplasty. Assessment of the two approaches consisted of determining the invasiveness through serum markers for muscle damage (i.e. myoglobin, creatine kinase and lactate dehydrogenase), the operative parameters such as post-operative pain and rescue medication consumption, the component positioning and complication rates. Post-operative myoglobin levels were higher (p < 0.001) in the LA group (326.42 ± 84.91 ng/mL) as compared to the DAA group (242.80 ± 71.03 ng/mL), but with no differences regarding other biomarkers for muscle damage. Pain levels were overall lower in the DAA group, with a statistical and clinical difference during surgery day (p < 0.001) associated with lower (p < 0.001) rescue medication consumption (median 1 (1; 3) mg morphine vs. 3 (2; 4) mg morphine). Most patients in the LA group reported chronic post-operative pain throughout all three evaluated months, while the majority of patients in the DAA group reported no pain after week six. Component positioning did not differ significantly between groups and neither did complication rates. The DAA can be transitioned from the LA safely, without higher complication rates while maintaining its muscle spearing advantages when performed by a low volume hip arthroplasty surgeon.

  20. Objects Architecture: A Comprehensive Design Approach for Real-Time, Distributed, Fault-Tolerant, Reactive Operating Systems.

    DTIC Science & Technology

    1987-09-01

    real - time operating system should be efficient from the real-time point...5,8]) system naming scheme. 3.2 Protecting Objects Real-time embedded systems usually neglect protection mechanisms. However, a real - time operating system cannot...allocation mechanism should adhere to application constraints. This strong relationship between a real - time operating system and the application

  1. CERT Resilience Management Model: A Maturity Model Approach to Managing Operational Resilience

    DTIC Science & Technology

    2010-07-28

    manufacturing, and energy 8 years @ SEI concentrating in information security risk management BS-Accounting; MBA Frequent lecturer in Carnegie...impact Move all operational risk management activities in the same direction Optimize cost/effectiveness Meet mission no-matter-what How do you...processes Effective operational risk management requires harmonization: convergence of these activities working toward the same goals Operational

  2. EOS Operations Systems: EDOS Implemented Changes to Reduce Operations Costs

    NASA Technical Reports Server (NTRS)

    Cordier, Guy R.; Gomez-Rosa, Carlos; McLemore, Bruce D.

    2007-01-01

    The authors describe in this paper the progress achieved to-date with the reengineering of the Earth Observing System (EOS) Data and Operations System (EDOS), the experience gained in the process and the ensuing reduction of ground systems operations costs. The reengineering effort included a major methodology change, applying to an existing schedule driven system, a data-driven system approach.

  3. Launch Vehicle Production and Operations Cost Metrics

    NASA Technical Reports Server (NTRS)

    Watson, Michael D.; Neeley, James R.; Blackburn, Ruby F.

    2014-01-01

    Traditionally, launch vehicle cost has been evaluated based on $/Kg to orbit. This metric is calculated based on assumptions not typically met by a specific mission. These assumptions include the specified orbit whether Low Earth Orbit (LEO), Geostationary Earth Orbit (GEO), or both. The metric also assumes the payload utilizes the full lift mass of the launch vehicle, which is rarely true even with secondary payloads.1,2,3 Other approaches for cost metrics have been evaluated including unit cost of the launch vehicle and an approach to consider the full program production and operations costs.4 Unit cost considers the variable cost of the vehicle and the definition of variable costs are discussed. The full program production and operation costs include both the variable costs and the manufacturing base. This metric also distinguishes operations costs from production costs, including pre-flight operational testing. Operations costs also consider the costs of flight operations, including control center operation and maintenance. Each of these 3 cost metrics show different sensitivities to various aspects of launch vehicle cost drivers. The comparison of these metrics provides the strengths and weaknesses of each yielding an assessment useful for cost metric selection for launch vehicle programs.

  4. On the Use of Kronecker Operators for the Solution of Generalized Stochastic Petri Nets

    NASA Technical Reports Server (NTRS)

    Ciardo, Gianfranco; Tilgner, Marco

    1996-01-01

    We discuss how to describe the Markov chain underlying a generalized stochastic Petri net using Kronecker operators on smaller matrices. We extend previous approaches by allowing both an extensive type of marking-dependent behavior for the transitions and the presence of immediate synchronizations. The derivation of the results is thoroughly formalized, including the use of Kronecker operators in the treatment of the vanishing markings and the computation of impulse-based reward measures. We use our techniques to analyze a model whose solution using conventional methods would fail because of the state-space explosion. In the conclusion, we point out ideas to parallelize our approach.

  5. The influence of protection system failures and preventive maintenance on protection systems in distribution systems

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

    Meeuwsen, J.J.; Kling, W.L.; Ploem, W.A.G.A.

    1997-01-01

    Protection systems in power systems can fail either by not responding when they should (failure to operate) or by operating when they should not (false tripping). The former type of failure is particularly serious since it may result in the isolation of large sections of the network. However, the probability of a failure to operate can be reduced by carrying out preventive maintenance on protection systems. This paper describes an approach to determine the impact of preventive maintenance on protection systems on the reliability of the power supply to customers. The proposed approach is based on Markov models.

  6. Determination of Sustainment Requirements for Operations by the U.S. Military in an Ice-free Arctic Using the Tenets of Operational Art

    DTIC Science & Technology

    2012-05-04

    human activity , and national security. A framework to address the changing Arctic exists within the U.S. government and U.S. military, but it is not mature. This paper performs an analysis of preparations made to date by the U.S. government and U.S. military for operations in an ice-free Arctic. The analysis revealed that the approach employed by the U.S. military consists of three tiers: promulgating strategic guidance, identifying missions and capability gaps, and gleaning lessons learned from exercises and war gaming. This approach has yielded benefits, but it is

  7. Innovative Test Operations to Support Orion and Future Human Rated Missions

    NASA Technical Reports Server (NTRS)

    Koenig, William J.; Garcia, Rafael; Harris, Richard F.; See, Michael J.; Van Lear, Benjamin S.; Dobson, Jill M.; Norris, Scott Douglas

    2017-01-01

    This paper describes how the Orion program is implementing new and innovative test approaches and strategies in an evolving development environment. The early flight test spacecraft are evolving in design maturity and complexity requiring significant changes in the ground test operations for each mission. The testing approach for EM-2 is planned to validate innovative Orion production acceptance testing methods to support human exploration missions in the future. Manufacturing and testing at Kennedy Space Center in the Neil Armstrong Operations and Checkout facility will provide a seamless transition directly to the launch site avoiding transportation and checkout of the spacecraft from other locations.

  8. A phased approach to induced seismicity risk management

    DOE PAGES

    White, Joshua A.; Foxall, William

    2014-01-01

    This work describes strategies for assessing and managing induced seismicity risk during each phase of a carbon storage project. We consider both nuisance and damage potential from induced earthquakes, as well as the indirect risk of enhancing fault leakage pathways. A phased approach to seismicity management is proposed, in which operations are continuously adapted based on available information and an on-going estimate of risk. At each project stage, specific recommendations are made for (a) monitoring and characterization, (b) modeling and analysis, and (c) site operations. The resulting methodology can help lower seismic risk while ensuring site operations remain practical andmore » cost-effective.« less

  9. Small satellite product assurance

    NASA Astrophysics Data System (ADS)

    Demontlivault, J.; Cadelec, Jacques

    1993-01-01

    In order to increase the interest in small satellites, their cost must be reduced; reducing product assurance costs induced by quality requirements is a major objective. For a logical approach, small satellites are classified in three main categories: satellites for experimental operations with a short lifetime, operational satellites manufactured in small mass with long lifetime requirements, operational satellites (long lifetime required), of which only a few models are produced. The various requirements as regards the product assurance are examined for each satellite category: general requirements for space approach, reliability, electronic components, materials and processes, quality assurance, documentation, tests, and management. Ideal product assurance system integrates quality teams and engineering teams.

  10. A Riemann-Hilbert approach to the inverse problem for the Stark operator on the line

    NASA Astrophysics Data System (ADS)

    Its, A.; Sukhanov, V.

    2016-05-01

    The paper is concerned with the inverse scattering problem for the Stark operator on the line with a potential from the Schwartz class. In our study of the inverse problem, we use the Riemann-Hilbert formalism. This allows us to overcome the principal technical difficulties which arise in the more traditional approaches based on the Gel’fand-Levitan-Marchenko equations, and indeed solve the problem. We also produce a complete description of the relevant scattering data (which have not been obtained in the previous works on the Stark operator) and establish the bijection between the Schwartz class potentials and the scattering data.

  11. Telepresence control of a dual-arm dexterous robot

    NASA Technical Reports Server (NTRS)

    Li, Larry; Cox, Brian; Shelton, Susan; Diftler, Myron

    1994-01-01

    Telepresence is an approach to teleoperation that provides egocentric, intuitive interactions between an operator and a remote environment. This approach takes advantage of the natural cognitive and sensory-motor skills of an on-orbit crew and effectively transfers them to a slave robot. A dual-arm dexterous robot operating under telepresence control has been developed and is being evaluated. Preliminary evaluation revealed several important observations that suggest the directions of future enhancement.

  12. Chondrosarcoma of the nasal septum: A case report.

    PubMed

    Kainuma, Kazuyuki; Netsu, Kiminori; Asamura, Kenji; Hayashi, Keiko; Takumi, Yutaka; Ota, Hiroyoshi; Usami, Shin-ichi

    2009-10-01

    Chondrosarcoma make up only 10-20% of malignant primary bone tumors, with 5-10% located in the head and neck (Downey TJ, Clark SK, Moore DW. Chondrosarcoma of the nasal septum. Otolaryngol Head Neck Surg 2001;125:98-100), and nasal septal chondrosarcoma is extremely rare. Surgical excision is the only curative treatment and radiation and chemotherapy have a limited role for palliation. We used a navigation system in endoscopic surgery without complications for a case of chondrosarcoma of the nasal septum by means of a midfacial degloving approach at primary operation and an external incision approach at salvage operation for local recurrence. To our knowledge, this is the first report of the use of such a system for this surgical approach along with a salvage operation. We discuss the clinical presentation, diagnosis, and treatment of this case as well as present a review of the literature.

  13. Towards a bootstrap approach to higher orders of epsilon expansion

    NASA Astrophysics Data System (ADS)

    Dey, Parijat; Kaviraj, Apratim

    2018-02-01

    We employ a hybrid approach in determining the anomalous dimension and OPE coefficient of higher spin operators in the Wilson-Fisher theory. First we do a large spin analysis for CFT data where we use results obtained from the usual and the Mellin bootstrap and also from Feynman diagram literature. This gives new predictions at O( ɛ 4) and O( ɛ 5) for anomalous dimensions and OPE coefficients, and also provides a cross-check for the results from Mellin bootstrap. These higher orders get contributions from all higher spin operators in the crossed channel. We also use the bootstrap in Mellin space method for ϕ 3 in d = 6 - ɛ CFT where we calculate general higher spin OPE data. We demonstrate a higher loop order calculation in this approach by summing over contributions from higher spin operators of the crossed channel in the same spirit as before.

  14. On the exact solvability of the anisotropic central spin model: An operator approach

    NASA Astrophysics Data System (ADS)

    Wu, Ning

    2018-07-01

    Using an operator approach based on a commutator scheme that has been previously applied to Richardson's reduced BCS model and the inhomogeneous Dicke model, we obtain general exact solvability requirements for an anisotropic central spin model with XXZ-type hyperfine coupling between the central spin and the spin bath, without any prior knowledge of integrability of the model. We outline basic steps of the usage of the operators approach, and pedagogically summarize them into two Lemmas and two Constraints. Through a step-by-step construction of the eigen-problem, we show that the condition gj‧2 - gj2 = c naturally arises for the model to be exactly solvable, where c is a constant independent of the bath-spin index j, and {gj } and { gj‧ } are the longitudinal and transverse hyperfine interactions, respectively. The obtained conditions and the resulting Bethe ansatz equations are consistent with that in previous literature.

  15. An approach for generating trajectory-based dynamics which conserves the canonical distribution in the phase space formulation of quantum mechanics. II. Thermal correlation functions.

    PubMed

    Liu, Jian; Miller, William H

    2011-03-14

    We show the exact expression of the quantum mechanical time correlation function in the phase space formulation of quantum mechanics. The trajectory-based dynamics that conserves the quantum canonical distribution-equilibrium Liouville dynamics (ELD) proposed in Paper I is then used to approximately evaluate the exact expression. It gives exact thermal correlation functions (of even nonlinear operators, i.e., nonlinear functions of position or momentum operators) in the classical, high temperature, and harmonic limits. Various methods have been presented for the implementation of ELD. Numerical tests of the ELD approach in the Wigner or Husimi phase space have been made for a harmonic oscillator and two strongly anharmonic model problems, for each potential autocorrelation functions of both linear and nonlinear operators have been calculated. It suggests ELD can be a potentially useful approach for describing quantum effects for complex systems in condense phase.

  16. Pipelining in a changing competitive environment

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

    Jones, E.G.; Wishart, D.M.

    1996-12-31

    The changing competitive environment for the pipeline industry presents a broad spectrum of new challenges and opportunities: international cooperation; globalization of opportunities, organizations and competition; and integrated systems approach to system configuration, financing, contracting strategy, materials sourcing, and operations; cutting edge and emerging technologies; adherence to high standards of environmental protection; an emphasis on safety; innovative approaches to project financing; and advances in technology and programs to maintain the long term, cost effective integrity of operating pipeline systems. These challenges and opportunities are partially a result of the increasingly competitive nature of pipeline development and the public`s intolerance to incidentsmore » of pipeline failure. A creative systems approach to these challenges is often the key to the project moving ahead. This usually encompasses collaboration among users of the pipeline, pipeline owners and operators, international engineering and construction companies, equipment and materials suppliers, in-country engineers and constructors, international lending agencies and financial institutions.« less

  17. Clinical governance and operations management methodologies.

    PubMed

    Davies, C; Walley, P

    2000-01-01

    The clinical governance mechanism, introduced since 1998 in the UK National Health Service (NHS), aims to deliver high quality care with efficient, effective and cost-effective patient services. Scally and Donaldson recognised that new approaches are needed, and operations management techniques comprise potentially powerful methodologies in understanding the process of care, which can be applied both within and across professional boundaries. This paper summarises four studies in hospital Trusts which took approaches to improving process that were different from and less structured than business process re-engineering (BPR). The problems were then amenable to change at a relatively low cost and short timescale, producing significant improvement to patient care. This less structured approach to operations management avoided incurring overhead costs of large scale and costly change such as new information technology (IT) systems. The most successful changes were brought about by formal tools to control quantity, content and timing of changes.

  18. Repressing the effects of variable speed harmonic orders in operational modal analysis

    NASA Astrophysics Data System (ADS)

    Randall, R. B.; Coats, M. D.; Smith, W. A.

    2016-10-01

    Discrete frequency components such as machine shaft orders can disrupt the operation of normal Operational Modal Analysis (OMA) algorithms. With constant speed machines, they have been removed using time synchronous averaging (TSA). This paper compares two approaches for varying speed machines. In one method, signals are transformed into the order domain, and after the removal of shaft speed related components by a cepstral notching method, are transformed back to the time domain to allow normal OMA. In the other simpler approach an exponential shortpass lifter is applied directly in the time domain cepstrum to enhance the modal information at the expense of other disturbances. For simulated gear signals with speed variations of both ±5% and ±15%, the simpler approach was found to give better results The TSA method is shown not to work in either case. The paper compares the results with those obtained using a stationary random excitation.

  19. An interactive modular design for computerized photometry in spectrochemical analysis

    NASA Technical Reports Server (NTRS)

    Bair, V. L.

    1980-01-01

    A general functional description of totally automatic photometry of emission spectra is not available for an operating environment in which the sample compositions and analysis procedures are low-volume and non-routine. The advantages of using an interactive approach to computer control in such an operating environment are demonstrated. This approach includes modular subroutines selected at multiple-option, menu-style decision points. This style of programming is used to trace elemental determinations, including the automated reading of spectrographic plates produced by a 3.4 m Ebert mount spectrograph using a dc-arc in an argon atmosphere. The simplified control logic and modular subroutine approach facilitates innovative research and program development, yet is easily adapted to routine tasks. Operator confidence and control are increased by the built-in options including degree of automation, amount of intermediate data printed out, amount of user prompting, and multidirectional decision points.

  20. The Aeronautical Data Link: Decision Framework for Architecture Analysis

    NASA Technical Reports Server (NTRS)

    Morris, A. Terry; Goode, Plesent W.

    2003-01-01

    A decision analytic approach that develops optimal data link architecture configuration and behavior to meet multiple conflicting objectives of concurrent and different airspace operations functions has previously been developed. The approach, premised on a formal taxonomic classification that correlates data link performance with operations requirements, information requirements, and implementing technologies, provides a coherent methodology for data link architectural analysis from top-down and bottom-up perspectives. This paper follows the previous research by providing more specific approaches for mapping and transitioning between the lower levels of the decision framework. The goal of the architectural analysis methodology is to assess the impact of specific architecture configurations and behaviors on the efficiency, capacity, and safety of operations. This necessarily involves understanding the various capabilities, system level performance issues and performance and interface concepts related to the conceptual purpose of the architecture and to the underlying data link technologies. Efficient and goal-directed data link architectural network configuration is conditioned on quantifying the risks and uncertainties associated with complex structural interface decisions. Deterministic and stochastic optimal design approaches will be discussed that maximize the effectiveness of architectural designs.

  1. Operational Art of Maritime Straits

    DTIC Science & Technology

    2008-10-29

    13  Operation CHEETAH ...Operational Art Paradigm Shift A strait is a narrow body of water navigationally constricted on two sides and usually connects two larger bodies of...level of risk. Space Space, in the terms of straits, encompasses more than just the body of water. Control of the approaches, shorelines and

  2. Beacon Spacecraft Operations: Lessons in Automation

    NASA Technical Reports Server (NTRS)

    Sherwood, R.; Schlutsmeyer, A.; Sue, M.; Szijjarto, J.; Wyatt, E. J.

    2000-01-01

    A new approach to mission operations has been flight validated on NASA's Deep Space One (DS1) mission that launched in October 1998. The beacon monitor operations technology is aimed at decreasing the total volume of downlinked engineering telemetry by reducing the frequency of downlink and the volume of data received per pass.

  3. A Structured, Yet Agile Approach to Designing C2 Operating Environments

    DTIC Science & Technology

    2012-06-01

    PROCESS ........................................................ 22 APPENDIX A: SUPPLEMENTAL MATERIAL...organization’s mission effectiveness. Lastly, he identifies the mechanisms for C2 agility, enabled by people, processes , information, systems...operations, controls forces, and coordinates operational activities and/or a facility that is organized to gather, process , analyze, dispatch, and

  4. Developing Students' Mathematical Skills Involving Order of Operations

    ERIC Educational Resources Information Center

    Ali Rahman, Ernna Sukinnah; Shahrill, Masitah; Abbas, Nor Arifahwati; Tan, Abby

    2017-01-01

    This small-scale action research study examines the students' ability in using their mathematical skills when performing order of operations in numerical expressions. In this study, the "hierarchy-of-operators triangle" by Ameis (2011) was introduced as an alternative BODMAS approach to help students in gaining a better understanding…

  5. A Systematic Approach for Real-Time Operator Functional State Assessment

    NASA Technical Reports Server (NTRS)

    Zhang, Guangfan; Wang, Wei; Pepe, Aaron; Xu, Roger; Schnell, Thomas; Anderson, Nick; Heitkamp, Dean; Li, Jiang; Li, Feng; McKenzie, Frederick

    2012-01-01

    A task overload condition often leads to high stress for an operator, causing performance degradation and possibly disastrous consequences. Just as dangerous, with automated flight systems, an operator may experience a task underload condition (during the en-route flight phase, for example), becoming easily bored and finding it difficult to maintain sustained attention. When an unexpected event occurs, either internal or external to the automated system, the disengaged operator may neglect, misunderstand, or respond slowly/inappropriately to the situation. In this paper, we discuss an approach for Operator Functional State (OFS) monitoring in a typical aviation environment. A systematic ground truth finding procedure has been designed based on subjective evaluations, performance measures, and strong physiological indicators. The derived OFS ground truth is continuous in time compared to a very sparse estimation of OFS based on an expert review or subjective evaluations. It can capture the variations of OFS during a mission to better guide through the training process of the OFS assessment model. Furthermore, an OFS assessment model framework based on advanced machine learning techniques was designed and the systematic approach was then verified and validated with experimental data collected in a high fidelity Boeing 737 simulator. Preliminary results show highly accurate engagement/disengagement detection making it suitable for real-time applications to assess pilot engagement.

  6. Mission operations management

    NASA Technical Reports Server (NTRS)

    Rocco, David A.

    1994-01-01

    Redefining the approach and philosophy that operations management uses to define, develop, and implement space missions will be a central element in achieving high efficiency mission operations for the future. The goal of a cost effective space operations program cannot be realized if the attitudes and methodologies we currently employ to plan, develop, and manage space missions do not change. A management philosophy that is in synch with the environment in terms of budget, technology, and science objectives must be developed. Changing our basic perception of mission operations will require a shift in the way we view the mission. This requires a transition from current practices of viewing the mission as a unique end product, to a 'mission development concept' built on the visualization of the end-to-end mission. To achieve this change we must define realistic mission success criteria and develop pragmatic approaches to achieve our goals. Custom mission development for all but the largest and most unique programs is not practical in the current budget environment, and we simply do not have the resources to implement all of our planned science programs. We need to shift our management focus to allow us the opportunity make use of methodologies and approaches which are based on common building blocks that can be utilized in the space, ground, and mission unique segments of all missions.

  7. Instantiating the art of war for effects-based operations

    NASA Astrophysics Data System (ADS)

    Burns, Carla L.

    2002-07-01

    Effects-Based Operations (EBO) is a mindset, a philosophy and an approach for planning, executing and assessing military operations for the effects they produce rather than the targets or even objectives they deal with. An EBO approach strives to provide economy of force, dynamic tasking, and reduced collateral damage. The notion of EBO is not new. Military Commanders certainly have desired effects in mind when conducting military operations. However, to date EBO has been an art of war that lacks automated techniques and tools that enable effects-based analysis and assessment. Modeling and simulation is at the heart of this challenge. The Air Force Research Laboratory (AFRL) EBO Program is developing modeling techniques and corresponding tool capabilities that can be brought to bear against the challenges presented by effects-based analysis and assessment. Effects-based course-of-action development, center of gravity/target system analysis, and wargaming capabilities are being developed and integrated to help give Commanders the information decision support required to achieve desired national security objectives. This paper presents an introduction to effects-based operations, discusses the benefits of an EBO approach, and focuses on modeling and analysis for effects-based strategy development. An overview of modeling and simulation challenges for EBO is presented, setting the stage for the detailed technical papers in the subject session.

  8. Application of fuzzy logic-neural network based reinforcement learning to proximity and docking operations: Special approach/docking testcase results

    NASA Technical Reports Server (NTRS)

    Jani, Yashvant

    1993-01-01

    As part of the RICIS project, the reinforcement learning techniques developed at Ames Research Center are being applied to proximity and docking operations using the Shuttle and Solar Maximum Mission (SMM) satellite simulation. In utilizing these fuzzy learning techniques, we use the Approximate Reasoning based Intelligent Control (ARIC) architecture, and so we use these two terms interchangeably to imply the same. This activity is carried out in the Software Technology Laboratory utilizing the Orbital Operations Simulator (OOS) and programming/testing support from other contractor personnel. This report is the final deliverable D4 in our milestones and project activity. It provides the test results for the special testcase of approach/docking scenario for the shuttle and SMM satellite. Based on our experience and analysis with the attitude and translational controllers, we have modified the basic configuration of the reinforcement learning algorithm in ARIC. The shuttle translational controller and its implementation in ARIC is described in our deliverable D3. In order to simulate the final approach and docking operations, we have set-up this special testcase as described in section 2. The ARIC performance results for these operations are discussed in section 3 and conclusions are provided in section 4 along with the summary for the project.

  9. Advancing reservoir operation description in physically based hydrological models

    NASA Astrophysics Data System (ADS)

    Anghileri, Daniela; Giudici, Federico; Castelletti, Andrea; Burlando, Paolo

    2016-04-01

    Last decades have seen significant advances in our capacity of characterizing and reproducing hydrological processes within physically based models. Yet, when the human component is considered (e.g. reservoirs, water distribution systems), the associated decisions are generally modeled with very simplistic rules, which might underperform in reproducing the actual operators' behaviour on a daily or sub-daily basis. For example, reservoir operations are usually described by a target-level rule curve, which represents the level that the reservoir should track during normal operating conditions. The associated release decision is determined by the current state of the reservoir relative to the rule curve. This modeling approach can reasonably reproduce the seasonal water volume shift due to reservoir operation. Still, it cannot capture more complex decision making processes in response, e.g., to the fluctuations of energy prices and demands, the temporal unavailability of power plants or varying amount of snow accumulated in the basin. In this work, we link a physically explicit hydrological model with detailed hydropower behavioural models describing the decision making process by the dam operator. In particular, we consider two categories of behavioural models: explicit or rule-based behavioural models, where reservoir operating rules are empirically inferred from observational data, and implicit or optimization based behavioural models, where, following a normative economic approach, the decision maker is represented as a rational agent maximising a utility function. We compare these two alternate modelling approaches on the real-world water system of Lake Como catchment in the Italian Alps. The water system is characterized by the presence of 18 artificial hydropower reservoirs generating almost 13% of the Italian hydropower production. Results show to which extent the hydrological regime in the catchment is affected by different behavioural models and reservoir operating strategies.

  10. Risk Based Reservoir Operations Using Ensemble Streamflow Predictions for Lake Mendocino in Mendocino County, California

    NASA Astrophysics Data System (ADS)

    Delaney, C.; Mendoza, J.; Whitin, B.; Hartman, R. K.

    2017-12-01

    Ensemble Forecast Operations (EFO) is a risk based approach of reservoir flood operations that incorporates ensemble streamflow predictions (ESPs) made by NOAA's California-Nevada River Forecast Center (CNRFC). With the EFO approach, each member of an ESP is individually modeled to forecast system conditions and calculate risk of reaching critical operational thresholds. Reservoir release decisions are computed which seek to manage forecasted risk to established risk tolerance levels. A water management model was developed for Lake Mendocino, a 111,000 acre-foot reservoir located near Ukiah, California, to evaluate the viability of the EFO alternative to improve water supply reliability but not increase downstream flood risk. Lake Mendocino is a dual use reservoir, which is owned and operated for flood control by the United States Army Corps of Engineers and is operated for water supply by the Sonoma County Water Agency. Due to recent changes in the operations of an upstream hydroelectric facility, this reservoir has suffered from water supply reliability issues since 2007. The EFO alternative was simulated using a 26-year (1985-2010) ESP hindcast generated by the CNRFC, which approximates flow forecasts for 61 ensemble members for a 15-day horizon. Model simulation results of the EFO alternative demonstrate a 36% increase in median end of water year (September 30) storage levels over existing operations. Additionally, model results show no increase in occurrence of flows above flood stage for points downstream of Lake Mendocino. This investigation demonstrates that the EFO alternative may be a viable approach for managing Lake Mendocino for multiple purposes (water supply, flood mitigation, ecosystems) and warrants further investigation through additional modeling and analysis.

  11. Laparoscopic versus open incisional hernia repair: a retrospective cohort study with costs analysis on 269 patients.

    PubMed

    Soliani, G; De Troia, A; Portinari, M; Targa, S; Carcoforo, P; Vasquez, G; Fisichella, P M; Feo, C V

    2017-08-01

    To compare clinical outcomes and institutional costs of elective laparoscopic and open incisional hernia mesh repairs and to identify independent predictors of prolonged operative time and hospital length of stay (LOS). Retrospective observational cohort study on 269 consecutive patients who underwent elective incisional hernia mesh repair, laparoscopic group (N = 94) and open group (N = 175), between May 2004 and July 2014. Operative time was shorter in the laparoscopic versus open group (p < 0.0001). Perioperative morbidity and mortality were similar in the two groups. Patients in the laparoscopic group were discharged a median of 2 days earlier (p < 0.0001). At a median follow-up over 50 months, no difference in hernia recurrence was detected between the groups. In laparoscopic group total institutional costs were lower (p = 0.02). At Cox regression analysis adjusted for potential confounders, large wall defect (W3) and higher operative risk (ASA score 3-4) were associated with prolonged operative time, while midline hernia site was associated with increased hospital LOS. Open surgical approach was associated with prolongation of both operative time and LOS. Laparoscopic approach may be considered safely to all patients for incisional hernia repair, regardless of patients' characteristics (age, gender, BMI, ASA score, comorbidities) and size of the wall defect (W2-3), with the advantage of shorter operating time and hospital LOS that yields reduced total institutional costs. Patients with higher ASA score and large hernia defects are at risk of prolonged operative time, while an open approach is associated with longer duration of surgical operation and hospital LOS.

  12. Principles of a clean operating room environment.

    PubMed

    Howard, James L; Hanssen, Arlen D

    2007-10-01

    Optimizing the operating room environment is necessary to minimize the prevalence of arthroplasty infection. Reduction of bacterial contamination in the operating room should be a primary focus of all members of the operating room team. However, in recent years, there has been a decline in the emphasis of the basic principles of antisepsis in many operating rooms. The purpose of this review is to highlight important considerations for optimizing the operating room environment. These principles should be actively promoted by orthopedic surgeons in their operating rooms as part of a comprehensive approach to minimizing arthroplasty infection.

  13. [The randomized controlled trial of influences of T shape approach on the function of knee joint in the treatment of proximal tibial fractures].

    PubMed

    Peng, Wei-xiong; Zhang, Zhi; Liang, Jie-hong

    2008-04-01

    To investigate the clinical value of T shape approach in the treatment of proximal tibial fractures. One handrend and thirteen patients of proximal tibial fractures were randomly divided into two groups. Group A: 62 cases underwent the traditional exposure approach. According to Schatzker classification,the cases of II to VI type was 25, 10, 16, 6, 5 respectively. Group B:51 cases underwent T shape approach ahead of knee joint, the cases of II to VI type was 21, 8, 13, 5, 4 respectively. All data were analyzed by SPSS 10.0 to compare operation time, blood loss, duration of hospitalization, healing time, the time of osseous union and complications after operation. Sixty patients in group A and 50 patients in group B were followed-up from 12 to 24 months. (1) Operation time:group B was longer than A (P < 0.01). (2) Mean blood loss and duration of hospitalization was the same. (3) Clinical healing time:group B was shorter. (4) Mean time of osseous union: 48 group B was shorter. Function of knee: group B was better than group A. (Complication: group B was less than group A. As compared with traditional exposure approach, T shape approach of knee joint had advantages of small scar, fewer complications, faster union of fracture and earlier recovery of joint function. The approach is valuable for the treatment of proximal tibial fractures.

  14. Strain expansion-reduction approach

    NASA Astrophysics Data System (ADS)

    Baqersad, Javad; Bharadwaj, Kedar

    2018-02-01

    Validating numerical models are one of the main aspects of engineering design. However, correlating million degrees of freedom of numerical models to the few degrees of freedom of test models is challenging. Reduction/expansion approaches have been traditionally used to match these degrees of freedom. However, the conventional reduction/expansion approaches are only limited to displacement, velocity or acceleration data. While in many cases only strain data are accessible (e.g. when a structure is monitored using strain-gages), the conventional approaches are not capable of expanding strain data. To bridge this gap, the current paper outlines a reduction/expansion technique to reduce/expand strain data. In the proposed approach, strain mode shapes of a structure are extracted using the finite element method or the digital image correlation technique. The strain mode shapes are used to generate a transformation matrix that can expand the limited set of measurement data. The proposed approach can be used to correlate experimental and analytical strain data. Furthermore, the proposed technique can be used to expand real-time operating data for structural health monitoring (SHM). In order to verify the accuracy of the approach, the proposed technique was used to expand the limited set of real-time operating data in a numerical model of a cantilever beam subjected to various types of excitations. The proposed technique was also applied to expand real-time operating data measured using a few strain gages mounted to an aluminum beam. It was shown that the proposed approach can effectively expand the strain data at limited locations to accurately predict the strain at locations where no sensors were placed.

  15. Neutron Spectrometer Prospecting During the Mojave Volatiles Project Analog Field Test

    NASA Technical Reports Server (NTRS)

    Elphic, R. C.; Heldmann, J. L.; Colaprete, A.; Hunt, D. R.; Deans, M C.; Lim, D. S.; Foil, G.; Fong, T.

    2015-01-01

    We know there are volatiles sequestered at the poles of the Moon. While we have evidence of water ice and a number of other compounds based on remote sensing, the detailed distribution, and physical and chemical form are largely unknown. Additional orbital studies of lunar polar volatiles may yield further insights, but the most important next step is to use landed assets to fully characterize the volatile composition and distribution at scales of tens to hundreds of meters. To achieve this range of scales, mobility is needed. Because of the proximity of the Moon, near real-time operation of the surface assets is possible, with an associated reduction in risk and cost. This concept of operations is very different from that of rovers on Mars, and new operational approaches are required to carry out such real-time robotic exploration. The Mojave Volatiles Project (MVP) is a Moon- Mars Analog Mission Activities (MMAMA) program effort aimed at (1) determining effective approaches to operating a real-time but short-duration lunar surface robotic mission, and (2) performing prospecting science in a natural setting, as a test of these approaches. We know there are volatiles sequestered at the poles of the Moon. While we have evidence of water ice and a number of other compounds based on remote sensing, the detailed distribution, and physical and chemical form are largely unknown. Additional orbital studies of lunar polar volatiles may yield further insights, but the most important next step is to use landed assets to fully characterize the volatile composition and distribution at scales of tens to hundreds of meters. To achieve this range of scales, mobility is needed. Because of the proximity of the Moon, near real-time operation of the surface assets is possible, with an associated reduction in risk and cost. This concept of operations is very different from that of rovers on Mars, and new operational approaches are required to carry out such robotic exploration. The Mojave Volatiles Project (MVP) is a Moon- Mars Analog Mission Activities (MMAMA) program effort aimed at (1) determining effective approaches to operating a real-time but short-duration lunar surface robotic mission, and (2) performing prospecting science in a natural setting, as a test of these approaches. Here we describe some results from the first such test, carried out in the Mojave Desert between 16 and 24 October, 2014. The test site was an alluvial fan just E of the Soda Mountains, SW of Baker, California. This site contains desert pavements, ranging from the late Pleistocene to early-Holocene in age. These pavements are undergoing dissection by the ongoing development of washes. A principal objective was to determine the hydration state of different types of desert pavement and bare ground features. The mobility element of the test was provided by the KREX-2 rover, designed and operated by the Intelligent Robotics Group at NASA Ames Research Center.

  16. Evaluation of the operatorial Q-system for non-compact super spin chains

    NASA Astrophysics Data System (ADS)

    Frassek, Rouven; Marboe, Christian; Meidinger, David

    2017-09-01

    We present an approach to evaluate the full operatorial Q-system of all u(p,q\\Big|r+s) -invariant spin chains with representations of Jordan-Schwinger type. In particular, this includes the super spin chain of planar N=4 super Yang-Mills theory at one loop in the presence of a diagonal twist. Our method is based on the oscillator construction of Q-operators. The Q-operators are built as traces over Lax operators which are degenerate solutions of the Yang-Baxter equation. For non-compact representations these Lax operators may contain multiple infinite sums that conceal the form of the resulting functions. We determine these infinite sums and calculate the matrix elements of the lowest level Q-operators. Transforming the Lax operators corresponding to the Q-operators into a representation involving only finite sums allows us to take the supertrace and to obtain the explicit form of the Q-operators in terms of finite matrices for a given magnon sector. Imposing the functional relations, we then bootstrap the other Q-operators from those of the lowest level. We exemplify this approach for non-compact spin - s spin chains and apply it to N=4 at the one-loop level using the BMN vacuum as an example.

  17. Optimizing Water Use and Hydropower Production in Operational Reservoir System Scheduling with RiverWare

    NASA Astrophysics Data System (ADS)

    Magee, T. M.; Zagona, E. A.

    2017-12-01

    Practical operational optimization of multipurpose reservoir systems is challenging for several reasons. Each purpose has its own constraints which may conflict with those of other purposes. While hydropower generation typically provides the bulk of the revenue, it is also among the lowest priority purposes. Each river system has important details that are specific to the location such as hydrology, reservoir storage capacity, physical limitations, bottlenecks, and the continuing evolution of operational policy. In addition, reservoir operations models include discrete, nonlinear, and nonconvex physical processes and if-then operating policies. Typically, the forecast horizon for scheduling needs to be extended far into the future to avoid near term (e.g., a few hours or a day) scheduling decisions that result in undesirable future states; this makes the computational effort much larger than may be expected. Put together, these challenges lead to large and customized mathematical optimization problems which must be solved efficiently to be of practical use. In addition, the solution process must be robust in an operational setting. We discuss a unique modeling approach in RiverWare that meets these challenges in an operational setting. The approach combines a Preemptive Linear Goal Programming optimization model to handle prioritized policies complimented by preprocessing and postprocessing with Rulebased Simulation to improve the solution with regard to nonlinearities, discrete issues, and if-then logic. An interactive policy language with a graphical user interface allows modelers to customize both the optimization and simulation based on the unique aspects of the policy for their system while the routine physical aspect of operations are modeled automatically. The modeler is aided by a set of compiled predefined functions and functions shared by other modelers. We illustrate the success of the approach with examples from daily use at the Tennessee Valley Authority, the Bonneville Power Administration, and public utility districts on the Mid-Columbia River. We discuss recent innovations to improve solution quality, robustness, and performance for these systems. We conclude with new modeling challenges to extend the modeling approach to other uses.

  18. Transtracheal single-point stent fixation in posttracheotomy tracheomalacia under cone-beam computer tomography guidance by transmural suturing with the Berci needle - a perspective on a new tool to avoid stent migration of Dumon stents.

    PubMed

    Hohenforst-Schmidt, Wolfgang; Linsmeier, Bernd; Zarogoulidis, Paul; Freitag, Lutz; Darwiche, Kaid; Browning, Robert; Turner, J Francis; Huang, Haidong; Li, Qiang; Vogl, Thomas; Zarogoulidis, Konstantinos; Brachmann, Johannes; Rittger, Harald

    2015-01-01

    Tracheomalacia or tracheobronchomalacia (TM or TBM) is a common problem especially for elderly patients often unfit for surgical techniques. Several surgical or minimally invasive techniques have already been described. Stenting is one option but in general long-time stenting is accompanied by a high complication rate. Stent removal is more difficult in case of self-expandable nitinol stents or metallic stents in general in comparison to silicone stents. The main disadvantage of silicone stents in comparison to uncovered metallic stents is migration and plugging. We compared the operation time and in particular the duration of a sufficient Dumon stent fixation with different techniques in a patient with severe posttracheotomy TM and strongly reduced mobility of the vocal cords due to Parkinson's disease. The combined approach with simultaneous Dumon stenting and endoluminal transtracheal externalized suture under cone-beam computer tomography guidance with the Berci needle was by far the fastest approach compared to a (not performed) surgical intervention, or even purely endoluminal suturing through the rigid bronchoscope. The duration of the endoluminal transtracheal externalized suture was between 5 minutes and 9 minutes with the Berci needle; the pure endoluminal approach needed 51 minutes. The alternative of tracheobronchoplasty was refused by the patient. In general, 180 minutes for this surgical approach is calculated. The costs of the different approaches are supposed to vary widely due to the fact that in Germany 1 minute in an operation room costs on average approximately 50-60€ inclusive of taxes. In our own hospital (tertiary level), it is nearly 30€ per minute in an operation room for a surgical approach. Calculating an additional 15 minutes for patient preparation and transfer to wake-up room, therefore a total duration inside the investigation room of 30 minutes, the cost per flexible bronchoscopy is per minute on average less than 6€. Although the Dumon stenting requires a set-up with more expensive anesthesiology accompaniment, which takes longer than a flexible investigation estimated at 1 hour in an operation room, still without calculation of the costs of the materials and specialized staff that the surgical approach would consume at least 3,000€ more than a minimally invasive approach performed with the Berci needle. This difference is due to the longer time of the surgical intervention which is calculated at approximately 180 minutes in comparison to the achieved non-surgical approach of 60 minutes in the operation suite.

  19. Hemi-transseptal Approach for Pituitary Surgery: A Follow-Up Study

    PubMed Central

    Fnais, Naif; Maio, Salvatore Di; Edionwe, Susan; Zeitouni, Anthony; Sirhan, Denis; Valdes, Constanza J.; Tewfik, Marc A.

    2016-01-01

    Objectives The hemi-transseptal (Hemi-T) approach was developed to overcome the potential drawbacks of the nasoseptal flap (NSF) in endoscopic endonasal transsphenoidal skull base surgery. In this study, we describe further refinements on the Hemi-T approach, and report long-term outcomes as compared with traditional methods of skull base reconstruction. Design A retrospective case-control study. Setting Montreal Neurological Institute and Jewish General Hospital, Montreal, Canada. Participants Patients who underwent endoscopic endonasal transsphenoidal approach to skull base pathology. Main Outcome Measures Operative time, CSF rhinorrhea, and postoperative nasal morbidity. Results A total of 105 patients underwent the Hemi-T approach versus 40 controls. Operative time was shorter using the Hemi-T technique (180.51 ± 56.9 vs. 202.9 ± 62 minutes; p = 0.048). The rates of nasal morbidity (septal perforation [5/102 vs. 6/37; p = 0.029] and mucosal adhesion [11/102 vs. 10/39 p = 0.027]), fascia lata harvest (21/100 vs. 18/39; p = 0.0028), and postoperative CSF leak rates (7/100 vs. 9/38; p = 0.006) were lower in the Hemi-T group. Conclusion Advantages of the Hemi-T approach over traditional exposure techniques include preservation of the nasal vascular pedicle, shorter operative time, reduced fascia lata harvest rates, and decreased nasal morbidity. PMID:28321378

  20. Transumbilical Thoracoscopy Versus Conventional Thoracoscopy for Lung Wedge Resection: Safety and Efficacy in a Live Canine Model.

    PubMed

    Chen, Tzu-Ping; Yen-Chu; Wu, Yi-Cheng; Yeh, Chi-Ju; Liu, Chien-Ying; Hsieh, Ming-Ju; Yuan, Hsu-Chia; Ko, Po-Jen; Liu, Yun-Hen

    2015-12-01

    Transumbilical single-port surgery has been associated with less postoperative pain and offers better cosmetic outcomes than conventional 3-port laparoscopic surgery. This study compares the safety and efficacy of transumbilical thoracoscopy and conventional thoracoscopy for lung wedge resection. The animals (n = 16) were randomly assigned to the transumbilical thoracoscopic approach group (n = 8) or conventional thoracoscopic approach group (n = 8). Transumbilical lung resection was performed via an umbilical incision and a diaphragmatic incision. In the conventional thoracoscopic group, lung resection was completed through a thoracic incision. For both procedures, we compared the surgical outcomes, for example, operating time and operative complications; physiologic parameters, for example, respiratory rate and body temperature; inflammatory parameters, for example, white blood cell count; and pulmonary parameters, for example, arterial blood gas levels. The animals were euthanized 2 weeks after the surgery for gross and histologic evaluations. The lung wedge resection was successfully performed in all animals. There was no significant difference in the mean operating times or complications between the transumbilical and the conventional thoracoscopic approach groups. With regard to the physiologic impact of the surgeries, the transumbilical approach was associated with significant elevations in body temperature on postoperative day 1, when compared with the standard thoracoscopic approach. This study suggests that both approaches for performing lung wedge resection were comparable in efficacy and postoperative complications. © The Author(s) 2014.

  1. The Hand-Assisted Laparoscopic Approach to Resection of Pancreatic Mucinous Cystic Neoplasms: An Underused Technique?

    PubMed

    Postlewait, Lauren M; Ethun, Cecilia G; McInnis, Mia R; Merchant, Nipun; Parikh, Alexander; Idrees, Kamran; Isom, Chelsea A; Hawkins, William; Fields, Ryan C; Strand, Matthew; Weber, Sharon M; Cho, Clifford S; Salem, Ahmed; Martin, Robert C G; Scoggins, Charles; Bentrem, David; Kim, Hong J; Carr, Jacquelyn; Ahmad, Syed; Abbott, Daniel; Wilson, Gregory C; Kooby, David A; Maithel, Shishir K

    2018-01-01

    Pancreatic mucinous cystic neoplasms (MCNs) are rare tumors typically of the distal pancreas that harbor malignant potential. Although resection is recommended, data are limited on optimal operative approaches to distal pancreatectomy for MCN. MCN resections (2000-2014; eight institutions) were included. Outcomes of minimally invasive and open MCN resections were compared. A total of 289 patients underwent distal pancreatectomy for MCN: 136(47%) minimally invasive and 153(53%) open. Minimally invasive procedures were associated with smaller MCN size (3.9 vs 6.8 cm; P = 0.001), lower operative blood loss (192 vs 392 mL; P = 0.001), and shorter hospital stay(5 vs 7 days; P = 0.001) compared with open. Despite higher American Society of Anesthesiologists class, hand-assisted (n = 46) had similar advantages as laparoscopic/robotic (n = 76). When comparing hand-assisted to open, although MCN size was slightly smaller (4.1 vs 6.8 cm; P = 0.001), specimen length, operative time, and nodal yield were identical. Similar to laparoscopic/robotic, hand-assisted had lower operative blood loss (161 vs 392 mL; P = 0.001) and shorter hospital stay (5 vs 7 days; P = 0.03) compared with open, without increased complications. Hand-assisted laparoscopic technique is a useful approach for MCN resection because specimen length, lymph node yield, operative time, and complication profiles are similar to open procedures, but it still offers the advantages of a minimally invasive approach. Hand-assisted laparoscopy should be considered as an alternative to open technique or as a successive step before converting from total laparoscopic to open distal pancreatectomy for MCN.

  2. A panoramic view of the skull base: systematic review of open and endoscopic endonasal approaches to four tumors.

    PubMed

    Graffeo, Christopher S; Dietrich, August R; Grobelny, Bartosz; Zhang, Meng; Goldberg, Judith D; Golfinos, John G; Lebowitz, Richard; Kleinberg, David; Placantonakis, Dimitris G

    2014-08-01

    Endoscopic endonasal surgery has been established as the safest approach to pituitary tumors, yet its role in other common skull base lesions has not been established. To answer this question, we carried out a systematic review of reported series of open and endoscopic endonasal approaches to four major skull base tumors: olfactory groove meningiomas (OGM), tuberculum sellae meningiomas (TSM), craniopharyngiomas (CRA), and clival chordomas (CHO). Data from 162 studies containing 5,701 patients were combined and compared for differences in perioperative mortality, gross total resection (GTR), cerebrospinal fluid (CSF) leak, neurological morbidity, post-operative visual function, post-operative anosmia, post-operative diabetes insipidus (DI), and post-operative obesity/hyperphagia. Weighted average rates for each outcome were calculated using relative study size. Our findings indicate similar rates of GTR and perioperative mortality between open and endoscopic approaches for all tumor types. CSF leak was increased after endoscopic surgery. Visual function symptoms were more likely to improve after endoscopic surgery for TSM, CRA, and CHO. Post-operative DI and obesity/hyperphagia were significantly increased after open resection in CRA. Recurrence rates per 1,000 patient-years of follow-up were higher in endoscopy for OGM, TSM, and CHO. Trends for open and endoscopic surgery suggested modest improvement in all outcomes over time. Our observations suggest that endonasal endoscopy is a safe alternative to craniotomy and may be preferred for certain tumor types. However, endoscopic surgery is associated with higher rates of CSF leak, and possibly increased recurrence rates. Prospective study with long-term follow-up is required to verify these preliminary observations.

  3. Radiation dose of nurses during IR procedures: a controlled trial evaluating operator alerts before nursing tasks.

    PubMed

    Komemushi, Atsushi; Suzuki, Satoshi; Sano, Akira; Kanno, Shohei; Kariya, Shuji; Nakatani, Miyuki; Yoshida, Rie; Kono, Yumiko; Ikeda, Koshi; Utsunomiya, Keita; Harima, Yoko; Komemushi, Sadao; Tanigawa, Noboru

    2014-08-01

    To compare radiation exposure of nurses when performing nursing tasks associated with interventional procedures depending on whether or not the nurses called out to the operator before approaching the patient. In a prospective study, 93 interventional radiology procedures were randomly divided into a call group and a no-call group; there were 50 procedures in the call group and 43 procedures in the no-call group. Two monitoring badges were used to calculate effective dose of nurses. In the call group, the nurse first told the operator she was going to approach the patient each time she was about to do so. In the no-call group, the nurse did not say anything to the operator when she was about to approach the patient. In all the nursing tasks, the equivalent dose at the umbilical level inside the lead apron was below the detectable limit. The equivalent dose at the sternal level outside the lead apron was 0.16 μSv ± 0.41 per procedure in the call group and 0.51 μSv ± 1.17 per procedure in the no-call group. The effective dose was 0.018 μSv ± 0.04 per procedure in the call group and 0.056 μSv ± 0.129 per procedure in the no-call group. The call group had a significantly lower radiation dose (P = .034). Radiation doses of nurses were lower in the group in which the nurse called to the operator before she approached the patient. Copyright © 2014 SIR. Published by Elsevier Inc. All rights reserved.

  4. Implementation and evaluation of a hypercube-based method for spatiotemporal exploration and analysis

    NASA Astrophysics Data System (ADS)

    Marchand, Pierre; Brisebois, Alexandre; Bédard, Yvan; Edwards, Geoffrey

    This paper presents the results obtained with a new type of spatiotemporal topological dimension implemented within a hypercube, i.e., within a multidimensional database (MDDB) structure formed by the conjunction of several thematic, spatial and temporal dimensions. Our goal is to support efficient SpatioTemporal Exploration and Analysis (STEA) in the context of Automatic Position Reporting System (APRS), the worldwide amateur radio system for position report transmission. Mobile APRS stations are equipped with GPS navigation systems to provide real-time positioning reports. Previous research about the multidimensional approach has proved good potential for spatiotemporal exploration and analysis despite a lack of explicit topological operators (spatial, temporal and spatiotemporal). Our project implemented such operators through a hierarchy of operators that are applied to pairs of instances of objects. At the top of the hierarchy, users can use simple operators such as "same place", "same time" or "same time, same place". As they drill down into the hierarchy, more detailed topological operators are made available such as "adjacent immediately after", "touch during" or more detailed operators. This hierarchy is structured according to four levels of granularity based on cognitive models, generalized relationships and formal models of topological relationships. In this paper, we also describe the generic approach which allows efficient STEA within the multidimensional approach. Finally, we demonstrate that such an implementation offers query run times which permit to maintain a "train-of-thought" during exploration and analysis operations as they are compatible with Newell's cognitive band (query runtime<10 s) (Newell, A., 1990. Unified theories of cognition. Harvard University Press, Cambridge MA, 549 p.).

  5. An Optimization Approach to Coexistence of Bluetooth and Wi-Fi Networks Operating in ISM Environment

    NASA Astrophysics Data System (ADS)

    Klajbor, Tomasz; Rak, Jacek; Wozniak, Jozef

    Unlicensed ISM band is used by various wireless technologies. Therefore, issues related to ensuring the required efficiency and quality of operation of coexisting networks become essential. The paper addresses the problem of mutual interferences between IEEE 802.11b transmitters (commercially named Wi-Fi) and Bluetooth (BT) devices.An optimization approach to modeling the topology of BT scatternets is introduced, resulting in more efficient utilization of ISM environment consisting of BT and Wi-Fi networks. To achieve it, the Integer Linear Programming approach has been proposed. Example results presented in the paper illustrate significant benefits of using the proposed modeling strategy.

  6. [Exploration of transnasal endoscopic cranialbase approach].

    PubMed

    Xu, Geng; Li, Yuan; Xie, Minqiang; Wen, Weiping; Shi, Jianbo; Chen, Hexin; Lu, Jianting; Zhang, Gehua; Liu, Xian; Xu, Rui

    2002-12-01

    To study feasibility and indication of cranialbase surgery by transnasal endoscopic approach. Nine cases treated by transnasal were analysed. Those cases included foreign body, olfactory neuroblastoma, meningoma and inverted papilloma in anterior cranial fossa, sinuses sphenoidalis macrosis cyst invading middle cranial fossa, primary cholesteatoma and space occupying lesion in middle cranial fossa. The complications were not occurred in all cases. Follow-up survey 1-7 years, no-relapse was occurred. It is probability that surgery lesion be close skull base by transnasal endoscopic approach, but indication must be exactitude selected. The operator should be have firm anatomic, skilled operation and richness experience. The malignancy lesion should be compositive treatment after surgery.

  7. Resource modeling: A reality for program cost analysis

    NASA Technical Reports Server (NTRS)

    Fouts, L. D.; Hurst, R. L. (Principal Investigator)

    1979-01-01

    The approach, implementation, operation, and utilization of a model to establish capital investment and operational costs for the Program is presented. These are based on their interrelationships, dependencies, and alternative actions.

  8. A robust generalized fuzzy operator approach to film contrast correction in digital subtraction radiography.

    PubMed

    Leung, Chung-Chu

    2006-03-01

    Digital subtraction radiography requires close matching of the contrast in each pair of X-ray images to be subtracted. Previous studies have shown that nonparametric contrast/brightness correction methods using the cumulative density function (CDF) and its improvements, which are based on gray-level transformation associated with the pixel histogram, perform well in uniform contrast/brightness difference conditions. However, for radiographs with nonuniform contrast/ brightness, the CDF produces unsatisfactory results. In this paper, we propose a new approach in contrast correction based on the generalized fuzzy operator with least square method. The result shows that 50% of the contrast/brightness errors can be corrected using this approach when the contrast/brightness difference between a radiographic pair is 10 U. A comparison of our approach with that of CDF is presented, and this modified GFO method produces better contrast normalization results than the CDF approach.

  9. A Mixed Integer Efficient Global Optimization Framework: Applied to the Simultaneous Aircraft Design, Airline Allocation and Revenue Management Problem

    NASA Astrophysics Data System (ADS)

    Roy, Satadru

    Traditional approaches to design and optimize a new system, often, use a system-centric objective and do not take into consideration how the operator will use this new system alongside of other existing systems. This "hand-off" between the design of the new system and how the new system operates alongside other systems might lead to a sub-optimal performance with respect to the operator-level objective. In other words, the system that is optimal for its system-level objective might not be best for the system-of-systems level objective of the operator. Among the few available references that describe attempts to address this hand-off, most follow an MDO-motivated subspace decomposition approach of first designing a very good system and then provide this system to the operator who decides the best way to use this new system along with the existing systems. The motivating example in this dissertation presents one such similar problem that includes aircraft design, airline operations and revenue management "subspaces". The research here develops an approach that could simultaneously solve these subspaces posed as a monolithic optimization problem. The monolithic approach makes the problem a Mixed Integer/Discrete Non-Linear Programming (MINLP/MDNLP) problem, which are extremely difficult to solve. The presence of expensive, sophisticated engineering analyses further aggravate the problem. To tackle this challenge problem, the work here presents a new optimization framework that simultaneously solves the subspaces to capture the "synergism" in the problem that the previous decomposition approaches may not have exploited, addresses mixed-integer/discrete type design variables in an efficient manner, and accounts for computationally expensive analysis tools. The framework combines concepts from efficient global optimization, Kriging partial least squares, and gradient-based optimization. This approach then demonstrates its ability to solve an 11 route airline network problem consisting of 94 decision variables including 33 integer and 61 continuous type variables. This application problem is a representation of an interacting group of systems and provides key challenges to the optimization framework to solve the MINLP problem, as reflected by the presence of a moderate number of integer and continuous type design variables and expensive analysis tool. The result indicates simultaneously solving the subspaces could lead to significant improvement in the fleet-level objective of the airline when compared to the previously developed sequential subspace decomposition approach. In developing the approach to solve the MINLP/MDNLP challenge problem, several test problems provided the ability to explore performance of the framework. While solving these test problems, the framework showed that it could solve other MDNLP problems including categorically discrete variables, indicating that the framework could have broader application than the new aircraft design-fleet allocation-revenue management problem.

  10. Defending the Driniumor. Covering Force Operations in New Guinea, 1944 (Leavenworth Papers, Number 9)

    DTIC Science & Technology

    1984-02-01

    remains Robert Ross Smith’s The Approach to the Philippines . This Leavenworth Paper adds tactical detail to a single phase of the complex operations...divisions, supported by the U.S. Pacific Fleet, attack Hollandia on 15 April as a step toward MacArt the Philippines . One week later, the JCS...controlling the southern approach to the Philippines and the Caroline Islands. The Japanese primary defense line, decided at an imperial conference on

  11. Design and development of pressure and repressurization purge system for reusable space shuttle multilayer insulation system

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Preliminary design and analysis of purge system concepts and purge subsystem approaches are defined and evaluated. Acceptable purge subsystem approaches were combined into four predesign layouts which are presented for comparison and evaluation. Two predesigns were selected for further detailed design and evaluation for eventual selection of the best design for a full scale test configuration. An operation plan is included as an appendix for reference to shuttle-oriented operational parameters.

  12. Space Station fluid management logistics

    NASA Technical Reports Server (NTRS)

    Dominick, Sam M.

    1990-01-01

    Viewgraphs and discussion on space station fluid management logistics are presented. Topics covered include: fluid management logistics - issues for Space Station Freedom evolution; current fluid logistics approach; evolution of Space Station Freedom fluid resupply; launch vehicle evolution; ELV logistics system approach; logistics carrier configuration; expendable fluid/propellant carrier description; fluid carrier design concept; logistics carrier orbital operations; carrier operations at space station; summary/status of orbital fluid transfer techniques; Soviet progress tanker system; and Soviet propellant resupply system observations.

  13. Intelligent Decisions? Intelligent Support? Agenda and Participants for the Internal Workshop on Intelligent Decision Support Systems : Retrospects and Prospects, August 29 - September 2, 2005, Certosa di Pontignano (Siena), Italy

    DTIC Science & Technology

    2005-09-01

    ENGINEERING APPROACH TO INTELLIGENT OPERATOR ASSISTANCE AND AUTONOMOUS VEHICLE GUIDANCE ..................100 27. SHARPLE, SARAH (WITH COX, GEMMA & STEDMON...104 30. TANGO, FABIO: CONCEPT OF AUTONOMIC COMPUTING APPLIED TO TRANSPORTATION ISSUES: THE SENSITIVE CAR .....105 31. TAYLOR, ROBERT: POSITION...SYSTEMS ENGINEERING APPROACH TO INTELLIGENT OPERATOR ASSISTANCE AND AUTONOMOUS VEHICLE GUIDANCE Today’s automation systems are typically introduced

  14. Modeling and Control of the Cobelli Model as a Personalized Prescriptive Tool for Diabetes Treatment

    DTIC Science & Technology

    2016-11-05

    within the body allow for a more quantified approach in medicine prescription as well as a deeper understanding of the discrete operations of...dynamics within the body allow for a more quantified approach in medicine prescription as well as a deeper understanding of the discrete operations of... discrete value) of the desired output (healthy blood glucose concentration in this project), yi is the ith sample of the measured output, ui is

  15. Brain Stem Cavernous Malformations: Operative Nuances of a Less-Invasive Resection Technique.

    PubMed

    Singh, Harminder; Elarjani, Turki; da Silva, Harley Brito; Shetty, Rakshith; Kim, Louis; Sekhar, Laligam N

    2017-12-08

    Different operative techniques are reported for the resection of brainstem cavernous malformations (BSCMs). The senior author has previously reported on a less-invasive technique of entering the brain stem with piecemeal removal of BSCMs, especially the deep-seated ones. To present a larger series of these lesions, emphasizing the approach to the brain stem via case selection. We discuss the nuances of the less-invasive operative technique through case illustrations and intraoperative videos. A retrospective review of 46 consecutive cases of BSCMs, with their clinical and radiographic data, was performed. Nine cases were selected to illustrate 7 different operative approaches, and discuss surgical nuances of the less-invasive technique unique to each. Postoperative morbidity, defined as an increase in modified Rankin Scale, was observed in 5 patients (10.9%). A residual BSCM was present in 2 patients (4.3%); both underwent reoperation to remove the remainder. At follow-up of 31.1 ± 27.8 mo, 3 patients experienced recurrence (6.5%). Overall, 65% of our patients improved, 20% stayed the same, and 11% worsened postsurgery. Two patients died, yielding a mortality of 4.3%. Using the less-invasive resection technique for piecemeal BSCM removal, in appropriately selected patients, has yielded comparable to improved patient outcomes over existing large series. In our experience, lateral, anterolateral, and posterolateral approaches are favorable over direct midline (dorsal or ventral) approaches. A thorough understanding of brain-stem safe-entry zones, in conjunction with appropriate approach selection, is key to a good outcome in challenging cases. Copyright © 2017 by the Congress of Neurological Surgeons

  16. Minimally invasive functional approach for cholesteatoma surgery.

    PubMed

    Hanna, Bassem M; Kivekäs, Ilkka; Wu, Yi-Hsuan; Guo, Lee J; Lin, Huang; Guidi, Jessica; Poe, Dennis

    2014-10-01

    Report the efficacy of a functional minimally invasive approach for cholesteatoma surgery. Retrospective review of surgical cases performed between 1996 and 2008. One hundred sixty-nine patient charts were reviewed in which ears with primary cholesteatomas that extended beyond the mesotympanum were operated on with a plan for canal wall up (CWU) mastoidectomy. The surgical approach consisted of progressive exposure from transcanal to postauricular tympanoplasty to CWU mastoidectomy, as needed, to identify and lyse the fibrous attachments that bind the capsule to the surrounding mucosa. Endoscopic guidance was employed as appropriate to minimize exposure needs. Any planned second-stage operations were attempted with a transcanal approach if appropriate and with endoscopic assistance. One hundred eighty-four ears of 169 patients were included. The median age was 32 years (range, 1-79 years). The mean follow-up was 3.2 years (range, 1-11 years). Eighty-three (45%) were planned for a second-look operation, and three (2%) required unplanned second operations. The overall recurrence rate was 24/184 (13%), and the unexpected residual rate was 5/184 (3%). The residual rate with endoscopy (5/119, 4%,) or without endoscopy (1/65, 2%), were not significantly different. Hearing results in 156 ears improved significantly, from a preoperative pure-tone average (PTA) of 41 dB to a postoperative PTA average of 29 dB (P < .0001). A functional minimally invasive approach to cholesteatoma surgery provided equivalent residual rates but higher recurrence rates compared to published canal wall down mastoidectomy. Endoscopic techniques were helpful in providing adequate views while minimizing exposure. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  17. Comparative use of different emission measurement approaches to determine methane emissions from a biogas plant.

    PubMed

    Reinelt, Torsten; Delre, Antonio; Westerkamp, Tanja; Holmgren, Magnus A; Liebetrau, Jan; Scheutz, Charlotte

    2017-10-01

    A sustainable anaerobic biowaste treatment has to mitigate methane emissions from the entire biogas production chain, but the exact quantification of these emissions remains a challenge. This study presents a comparative measurement campaign carried out with on-site and ground-based remote sensing measurement approaches conducted by six measuring teams at a Swedish biowaste treatment plant. The measured emissions showed high variations, amongst others caused by different periods of measurement performance in connection with varying operational states of the plant. The overall methane emissions measured by ground-based remote sensing varied from 5 to 25kgh -1 (corresponding to a methane loss of 0.6-3.0% of upgraded methane produced), depending on operating conditions and the measurement method applied. Overall methane emissions measured by the on-site measuring approaches varied between 5 and 17kgh -1 (corresponding to a methane loss of 0.6 and 2.1%) from team to team, depending on the number of measured emission points, operational state during the measurements and the measurement method applied. Taking the operational conditions into account, the deviation between different approaches and teams could be explained, in that the two largest methane-emitting sources, contributing about 90% of the entire site's emissions, were found to be the open digestate storage tank and a pressure release valve on the compressor station. Copyright © 2017. Published by Elsevier Ltd.

  18. NASA/ARMY/BELL XV-15 Tiltrotor Low-Noise Terminal Area Operations Flight Research Program

    NASA Technical Reports Server (NTRS)

    Edwards, Bryan D.; Conner, David A.; Decker, William A.; Marcolini, Michael A.; Klein, Peter D.

    2001-01-01

    To evaluate the noise reduction potential for tiltrotor aircraft, a series of three XV- 15 acoustic flight tests were conducted over a five-year period by a NASA/Army/Bell Helicopter team. Lower hemispherical noise characteristics for a wide range of steady-state terminal area type operating conditions were measured during the Phase I test and indicated that the takeoff and level flight conditions were not significant contributors to the total noise of tiltrotor operations. Phase I results were also used to design low-noise approach profiles that were tested later during the Phase 2 and Phase 3 tests. These latter phases used large area microphone arrays to directly measure ground noise footprints. Approach profiles emphasized noise reduction while maintaining handling qualities sufficient for tiltrotor commercial passenger ride comfort and flight safety under Instrument Flight Rules (IFR) conditions. This paper will discuss the weather, aircraft, tracking, guidance, and acoustic instrumentation systems, as well as the approach profile design philosophy, and the overall test program philosophy. Acoustic results are presented to document the variation in tiltrotor noise due to changes in operating condition, indicating the potential for significant noise reduction using the unique tiltrotor capability of nacelle tilt. Recommendations are made for a final XV-15 test to define the acoustic benefits of the automated approach capability which has recently been added to this testbed aircraft.

  19. Commercial Flight Crew Decision-Making during Low-Visibility Approach Operations Using Fused Synthetic/Enhanced Vision Systems

    NASA Technical Reports Server (NTRS)

    Kramer, Lynda J.; Bailey, Randall E.; Prinzel, Lawrence J., III

    2007-01-01

    NASA is investigating revolutionary crew-vehicle interface technologies that strive to proactively overcome aircraft safety barriers that would otherwise constrain the full realization of the next-generation air transportation system. A fixed-based piloted simulation experiment was conducted to evaluate the complementary use of Synthetic and Enhanced Vision technologies. Specific focus was placed on new techniques for integration and/or fusion of Enhanced and Synthetic Vision and its impact within a two-crew flight deck on the crew's decision-making process during low-visibility approach and landing operations. Overall, the experimental data showed that significant improvements in situation awareness, without concomitant increases in workload and display clutter, could be provided by the integration and/or fusion of synthetic and enhanced vision technologies for the pilot-flying and the pilot-not-flying. During non-normal operations, the ability of the crew to handle substantial navigational errors and runway incursions were neither improved nor adversely impacted by the display concepts. The addition of Enhanced Vision may not, unto itself, provide an improvement in runway incursion detection without being specifically tailored for this application. Existing enhanced vision system procedures were effectively used in the crew decision-making process during approach and missed approach operations but having to forcibly transition from an excellent FLIR image to natural vision by 100 ft above field level was awkward for the pilot-flying.

  20. [The clinical effect and disquisition of anterior cervical approach surgery with posterior longitudinal ligament hook pliers and posterior longitudinal ligament nip pliers].

    PubMed

    Kuang, Ling-hao; Xu, Dong; Sun, Ya-wei; Cong, Jie; Tian, Ji-wei; Wang, Lei

    2010-09-21

    To study the clinical effect of anterior cervical approach surgery to removal posterior longitudinal ligament (PLL) with posterior longitudinal ligament hook pliers and posterior longitudinal ligament nip pliers. To retrospectively analyzed anterior cervical approach surgery treatment 73 patients who were cervical spondylosis myelopathy. All patients removal PLL with self-make instrument, According to JOA grade to evaluate effect of operations. Full patients removal PLL were in succeed, in shape of extradural has renew, the JOA grade were increase, (12.8 ± 3.2) vs (8.3 ± 1.9). Removal PLL were increase effect of downright decompress in anterior cervical approach surgery, Operations become safety agile and reduce the complications with self-make instrument.

  1. Learning the Task Management Space of an Aircraft Approach Model

    NASA Technical Reports Server (NTRS)

    Krall, Joseph; Menzies, Tim; Davies, Misty

    2014-01-01

    Validating models of airspace operations is a particular challenge. These models are often aimed at finding and exploring safety violations, and aim to be accurate representations of real-world behavior. However, the rules governing the behavior are quite complex: nonlinear physics, operational modes, human behavior, and stochastic environmental concerns all determine the responses of the system. In this paper, we present a study on aircraft runway approaches as modeled in Georgia Tech's Work Models that Compute (WMC) simulation. We use a new learner, Genetic-Active Learning for Search-Based Software Engineering (GALE) to discover the Pareto frontiers defined by cognitive structures. These cognitive structures organize the prioritization and assignment of tasks of each pilot during approaches. We discuss the benefits of our approach, and also discuss future work necessary to enable uncertainty quantification.

  2. Application of Satellite Based Augmentation Systems to Altitude Separation

    NASA Astrophysics Data System (ADS)

    Magny, Jean Pierre

    This paper presents the application of GNSS1, or more precisely of Satellite Based Augmentation Systems (SBAS), to vertical separation for en-route, approach and landing operations. Potential improvements in terms of operational benefit and of safety are described for two main applications. First, vertical separation between en-route aircraft, which requires a system available across wide areas. SBAS (EGNOS, WAAS, and MSAS) are very well suited for this purpose before GNSS2 becomes available. And secondly, vertical separation from the ground during approach and landing, for which preliminary design principles of instrument approach procedures and safety issues are presented. Approach and landing phases are the subject of discussions within ICAO GNSS-P. En-route phases have been listed as GNSS-P future work and by RTCA for development of new equipments.

  3. A contemporary view of systems engineering. [definition of system and discussion of systems approach

    NASA Technical Reports Server (NTRS)

    Miles, R. F., Jr.

    1974-01-01

    The concept of a 'system' is defined, and the 'systems approach' is discussed. Four contemporary examples of the systems approach are presented: an operations research project, the planning-programming-budgeting system, an information processing system, and aerospace programs.

  4. 75 FR 62457 - Establishment of Class E Airspace; Port Clarence, AK

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-12

    ... airstrip and has developed a military-use instrument approach procedure. This instrument approach procedure... Class E airspace for air traffic management of Instrument Flight Rules (IFR) operations. DATES... published in the notice of proposed rulemaking. The establishment of an instrument approach procedure...

  5. Millimeter-Wave Localizers for Aircraft-to-Aircraft Approach Navigation

    NASA Technical Reports Server (NTRS)

    Tang, Adrian J.

    2013-01-01

    Aerial refueling technology for both manned and unmanned aircraft is critical for operations where extended aircraft flight time is required. Existing refueling assets are typically manned aircraft, which couple to a second aircraft through the use of a refueling boom. Alignment and mating of the two aircraft continues to rely on human control with use of high-resolution cameras. With the recent advances in unmanned aircraft, it would be highly advantageous to remove/reduce human control from the refueling process, simplifying the amount of remote mission management and enabling new operational scenarios. Existing aerial refueling uses a camera, making it non-autonomous and prone to human error. Existing commercial localizer technology has proven robust and reliable, but not suited for aircraft-to-aircraft approaches like in aerial refueling scenarios since the resolution is too coarse (approximately one meter). A localizer approach system for aircraft-to-aircraft docking can be constructed using the same modulation with a millimeterwave carrier to provide high resolution. One technology used to remotely align commercial aircraft on approach to a runway are ILS (instrument landing systems). ILS have been in service within the U.S. for almost 50 years. In a commercial ILS, two partially overlapping beams of UHF (109 to 126 MHz) are broadcast from an antenna array so that their overlapping region defines the centerline of the runway. This is called a localizer system and is responsible for horizontal alignment of the approach. One beam is modulated with a 150-Hz tone, while the other with a 90-Hz tone. Through comparison of the modulation depths of both tones, an autopilot system aligns the approaching aircraft with the runway centerline. A similar system called a glide-slope (GS) exists in the 320-to-330MHz band for vertical alignment of the approach. While this technology has been proven reliable for millions of commercial flights annually, its UHF nature limits its ability to operate beyond the 1-to-2-meter precisions associated with commercial runway width. A prototype ILS-type system operates at millimeter-wave frequencies to provide automatic and robust approach control for aerial refueling. The system allows for the coupling process to remain completely autonomous, as a boom operator is no longer required. Operating beyond 100 GHz provides enough resolution and a narrow enough beamwidth that an approach corridor of centimeter scales can be maintained. Two modules were used to accomplish this task. The first module is a localizer/glide-slope module that can be fitted on a refueling aircraft. This module provides the navigation beams for aligning the approaching aircraft. The second module is navigational receiver fitted onto the approaching aircraft to be re fueled that can detect the approach beams. Since unmanned aircraft have a limited payload size and limited electrical power, the receiver portion was implemented in CMOS (complementary metal oxide semiconductor) technology based on a super-regenerative receiver (SRR) architecture. The SRR achieves mW-level power consumption and chip sizes less than l mm2. While super-regenerative techniques have small bandwidths that limit use in communication systems, their advantages of high sensitivity, low complexity, and low power make them ideal in this situation where modulating tones of less than 1 kHz are used.

  6. Guided wave tomography in anisotropic media using recursive extrapolation operators

    NASA Astrophysics Data System (ADS)

    Volker, Arno

    2018-04-01

    Guided wave tomography is an advanced technology for quantitative wall thickness mapping to image wall loss due to corrosion or erosion. An inversion approach is used to match the measured phase (time) at a specific frequency to a model. The accuracy of the model determines the sizing accuracy. Particularly for seam welded pipes there is a measurable amount of anisotropy. Moreover, for small defects a ray-tracing based modelling approach is no longer accurate. Both issues are solved by applying a recursive wave field extrapolation operator assuming vertical transverse anisotropy. The inversion scheme is extended by not only estimating the wall loss profile but also the anisotropy, local material changes and transducer ring alignment errors. This makes the approach more robust. The approach will be demonstrated experimentally on different defect sizes, and a comparison will be made between this new approach and an isotropic ray-tracing approach. An example is given in Fig. 1 for a 75 mm wide, 5 mm deep defect. The wave field extrapolation based tomography clearly provides superior results.

  7. Development and Deployment of Systems-Based Approaches for the Management of Soilborne Plant Pathogens.

    PubMed

    Chellemi, D O; Gamliel, A; Katan, J; Subbarao, K V

    2016-03-01

    Biological suppression of soilborne diseases with minimal use of outside interventive actions has been difficult to achieve in high input conventional crop production systems due to the inherent risk of pest resurgence. This review examines previous approaches to the management of soilborne disease as precursors to the evolution of a systems-based approach, in which plant disease suppression through natural biological feedback mechanisms in soil is incorporated into the design and operation of cropping systems. Two case studies are provided as examples in which a systems-based approach is being developed and deployed in the production of high value crops: lettuce/strawberry production in the coastal valleys of central California (United States) and sweet basil and other herb crop production in Israel. Considerations for developing and deploying system-based approaches are discussed and operational frameworks and metrics to guide their development are presented with the goal of offering a credible alternative to conventional approaches to soilborne disease management.

  8. Constraints and System Primitives in Achieving Multilevel Security in Real Time Distributed System Environment

    DTIC Science & Technology

    1994-04-18

    because they represent a microkernel and monolithic kernel approach to MLS operating system issues. TMACH is I based on MACH, a distributed operating...the operating system is [L.sed on a microkernel design or a monolithic kernel design. This distinction requires some caution since monolithic operating...are provided by 3 user-level processes, in contrast to standard UNIX, which has a large monolithic kernel that pro- I - 22 - Distributed O)perating

  9. Methodology for Designing Operational Banking Risks Monitoring System

    NASA Astrophysics Data System (ADS)

    Kostjunina, T. N.

    2018-05-01

    The research looks at principles of designing an information system for monitoring operational banking risks. A proposed design methodology enables one to automate processes of collecting data on information security incidents in the banking network, serving as the basis for an integrated approach to the creation of an operational risk management system. The system can operate remotely ensuring tracking and forecasting of various operational events in the bank network. A structure of a content management system is described.

  10. AQUILA Remotely Piloted Vehicle System Technology Demonstrator (RPV-STD) Program. Volume I. System Description and Capabilities

    DTIC Science & Technology

    1979-04-01

    tools, simplification of equipment interfaces involved in manual operations to provide simple system preparation, closing flight control inner loops ...alti- tude, and heading rate. The closed loops operate in three primary modes: cruise, dead reckoning, and approach. The aircraft is stabilized by...onboard closed loops , so the operator is not required to maintain hands-on operation to keep it in the air. The operator is able to command airspeed

  11. Comparison of approaches to Total Quality Management. Including an examination of the Department of Energy`s position on quality management

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

    Bennett, C.T.

    1994-03-01

    This paper presents a comparison of several qualitatively different approaches to Total Quality Management (TQM). The continuum ranges from management approaches that are primarily standards -- with specific guidelines, but few theoretical concepts -- to approaches that are primarily philosophical, with few specific guidelines. The approaches to TQM discussed in this paper include the International Organization for Standardization (ISO) 9000 Standard, the Malcolm Baldrige National Quality Award, Senge`s the Learning Organization, Watkins and Marsick`s approach to organizational learning, Covey`s Seven Habits of Highly Successful People, and Deming`s Fourteen Points for Management. Some of these approaches (Deming and ISO 9000) aremore » then compared to the DOE`s official position on quality management and conduct of operations (DOE Orders 5700.6C and 5480.19). Using a tabular format, it is shown that while 5700.6C (Quality Assurance) maps well to many of the current approaches to TQM, DOE`s principle guide to management Order 5419.80 (Conduct of Operations) has many significant conflicts with some of the modern approaches to continuous quality improvement.« less

  12. Travel Survey Manual: Appendices

    DOT National Transportation Integrated Search

    1995-02-01

    The primary objectives of this chapter are to provide information on the current physical and operating characteristics of all border crossings, including approaches and egresses, and to identify problems, both physical and operational, that affect t...

  13. Qubit-Programmable Operations on Quantum Light Fields

    PubMed Central

    Barbieri, Marco; Spagnolo, Nicolò; Ferreyrol, Franck; Blandino, Rémi; Smith, Brian J.; Tualle-Brouri, Rosa

    2015-01-01

    Engineering quantum operations is a crucial capability needed for developing quantum technologies and designing new fundamental physics tests. Here we propose a scheme for realising a controlled operation acting on a travelling continuous-variable quantum field, whose functioning is determined by a discrete input qubit. This opens a new avenue for exploiting advantages of both information encoding approaches. Furthermore, this approach allows for the program itself to be in a superposition of operations, and as a result it can be used within a quantum processor, where coherences must be maintained. Our study can find interest not only in general quantum state engineering and information protocols, but also details an interface between different physical platforms. Potential applications can be found in linking optical qubits to optical systems for which coupling is best described in terms of their continuous variables, such as optomechanical devices. PMID:26468614

  14. [Application of damage control surgery idea in the treatment of severe pancreatic duodenal injury].

    PubMed

    Zhu, Ren-wu; Gu, Ye-chun; Jiang, Yang-gui; Zhao, Mao-sen; Shen, Xian

    2013-12-01

    To explore the significance of damage control surgery (DCS) in the treatments of severe pancreaticoduodenal injuries. Clinical data of 19 patients with severe pancreaticoduodenal injuries managed with DCS approach in Wenzhou Hospital of Integrated Traditional Chinese and Western Medicine and the First Affiliated Hospital of Wenzhou Medical College from March 2005 to January 2013 were analyzed retrospectively. Three cases were cured after damage control operation and postoperative ICU resuscitation treatment. Twelve cases underwent definite operations (distal pancreaticojejunal Roux-en-Y anastomosis, proximal duodenojejunal Roux-en-Y anastomosis or pancreaticoduodenectomy) after damage control operation and postoperative ICU resuscitation treatment and cured. Four cases died after damage control operation due to multiple organ failure and the mortality was 21.1%. Application of DCS approach can improve the prognosis of patients with severe pancreaticoduodenal injuries.

  15. Performance and optimization of a derated ion thruster for auxiliary propulsion

    NASA Technical Reports Server (NTRS)

    Patterson, Michael J.; Foster, John E.

    1991-01-01

    The characteristics and implications of use of a derated ion thruster for north-south stationkeeping (NSSK) propulsion are discussed. A derated thruster is a 30 cm diameter primary propulsion ion thruster operated at highly throttled conditions appropriate to NSSK functions. The performance characteristics of a 30 cm ion thruster are presented, emphasizing throttled operation at low specific impulse and high thrust-to-power ratio. Performance data and component erosion are compared to other NSSK ion thrusters. Operations benefits derived from the performance advantages of the derated approach are examined assuming an INTELSAt 7-type spacecraft. Minimum ground test facility pumping capabilities required to maintain facility enhanced accelerator grid erosion at acceptable levels in a lifetest are quantified as a function of thruster operating condition. Approaches to reducing the derated thruster mass and volume are also discussed.

  16. Naturalistic Decision Making For Power System Operators

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

    Greitzer, Frank L.; Podmore, Robin; Robinson, Marck

    2009-06-23

    Abstract: Motivation -- As indicated by the Blackout of 2003, the North American interconnected electric system is vulnerable to cascading outages and widespread blackouts. Investigations of large scale outages often attribute the causes to the three T’s: Trees, Training and Tools. A systematic approach has been developed to document and understand the mental processes that an expert power system operator uses when making critical decisions. The approach has been developed and refined as part of a capability demonstration of a high-fidelity real-time power system simulator under normal and emergency conditions. To examine naturalistic decision making (NDM) processes, transcripts of operator-to-operatormore » conversations are analyzed to reveal and assess NDM-based performance criteria. Findings/Design -- The results of the study indicate that we can map the Situation Awareness Level of the operators at each point in the scenario. We can also identify clearly what mental models and mental simulations are being performed at different points in the scenario. As a result of this research we expect that we can identify improved training methods and improved analytical and visualization tools for power system operators. Originality/Value -- The research applies for the first time, the concepts of Recognition Primed Decision Making, Situation Awareness Levels and Cognitive Task Analysis to training of electric power system operators. Take away message -- The NDM approach provides an ideal framework for systematic training management and mitigation to accelerate learning in team-based training scenarios with high-fidelity power grid simulators.« less

  17. Group-wise feature-based registration of CT and ultrasound images of spine

    NASA Astrophysics Data System (ADS)

    Rasoulian, Abtin; Mousavi, Parvin; Hedjazi Moghari, Mehdi; Foroughi, Pezhman; Abolmaesumi, Purang

    2010-02-01

    Registration of pre-operative CT and freehand intra-operative ultrasound of lumbar spine could aid surgeons in the spinal needle injection which is a common procedure for pain management. Patients are always in a supine position during the CT scan, and in the prone or sitting position during the intervention. This leads to a difference in the spinal curvature between the two imaging modalities, which means a single rigid registration cannot be used for all of the lumbar vertebrae. In this work, a method for group-wise registration of pre-operative CT and intra-operative freehand 2-D ultrasound images of the lumbar spine is presented. The approach utilizes a pointbased registration technique based on the unscented Kalman filter, taking as input segmented vertebrae surfaces in both CT and ultrasound data. Ultrasound images are automatically segmented using a dynamic programming approach, while the CT images are semi-automatically segmented using thresholding. Since the curvature of the spine is different between the pre-operative and the intra-operative data, the registration approach is designed to simultaneously align individual groups of points segmented from each vertebra in the two imaging modalities. A biomechanical model is used to constrain the vertebrae transformation parameters during the registration and to ensure convergence. The mean target registration error achieved for individual vertebrae on five spine phantoms generated from CT data of patients, is 2.47 mm with standard deviation of 1.14 mm.

  18. Managing NASA's International Space Station Logistics and Maintenance Program

    NASA Technical Reports Server (NTRS)

    Butina, Anthony

    2001-01-01

    The International Space Station's Logistics and Maintenance program has had to develop new technologies and a management approach for both space and ground operations. The ISS will be a permanently manned orbiting vehicle that has no landing gear, no international borders, and no organizational lines - it is one Station that must be supported by one crew, 24 hours a day, 7 days a week, 365 days a year. It flies partially assembled for a number of years before it is finally completed in 2006. It has over 6,000 orbital replaceable units (ORU), and spare parts which number into the hundreds of thousands, from 127 major US vendors and 70 major international vendors. From conception to operation, the ISS requires a unique approach in all aspects of development and operations. Today the dream is coming true; hardware is flying and hardware is failing. The system has been put into place to support the Station for both space and ground operations. It started with the basic support concept developed for Department of Defense systems, and then it was tailored for the unique requirements of a manned space vehicle. Space logistics is a new concept that has wide reaching consequences for both space travel and life on Earth. This paper discusses what type of organization has been put into place to support both space and ground operations and discusses each element of that organization. In addition, some of the unique operations approaches this organization has had to develop is discussed.

  19. Flu Diagnosis System Using Jaccard Index and Rough Set Approaches

    NASA Astrophysics Data System (ADS)

    Efendi, Riswan; Azah Samsudin, Noor; Mat Deris, Mustafa; Guan Ting, Yip

    2018-04-01

    Jaccard index and rough set approaches have been frequently implemented in decision support systems with various domain applications. Both approaches are appropriate to be considered for categorical data analysis. This paper presents the applications of sets operations for flu diagnosis systems based on two different approaches, such as, Jaccard index and rough set. These two different approaches are established using set operations concept, namely intersection and subset. The step-by-step procedure is demonstrated from each approach in diagnosing flu system. The similarity and dissimilarity indexes between conditional symptoms and decision are measured using Jaccard approach. Additionally, the rough set is used to build decision support rules. Moreover, the decision support rules are established using redundant data analysis and elimination of unclassified elements. A number data sets is considered to attempt the step-by-step procedure from each approach. The result has shown that rough set can be used to support Jaccard approaches in establishing decision support rules. Additionally, Jaccard index is better approach for investigating the worst condition of patients. While, the definitely and possibly patients with or without flu can be determined using rough set approach. The rules may improve the performance of medical diagnosis systems. Therefore, inexperienced doctors and patients are easier in preliminary flu diagnosis.

  20. 33 CFR 401.51 - Signaling approach to a bridge.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Signaling approach to a bridge... approach to a bridge. (a) Unless a vessel's approach has been recognized by a flashing signal, the master shall signal the vessel's presence to the bridge operator by VHF radio when it comes abreast of any of...

  1. 33 CFR 401.51 - Signaling approach to a bridge.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Signaling approach to a bridge... approach to a bridge. (a) Unless a vessel's approach has been recognized by a flashing signal, the master shall signal the vessel's presence to the bridge operator by VHF radio when it comes abreast of any of...

  2. Incorporating teleconnection information into reservoir operating policies using Stochastic Dynamic Programming and a Hidden Markov Model

    NASA Astrophysics Data System (ADS)

    Turner, Sean; Galelli, Stefano; Wilcox, Karen

    2015-04-01

    Water reservoir systems are often affected by recurring large-scale ocean-atmospheric anomalies, known as teleconnections, that cause prolonged periods of climatological drought. Accurate forecasts of these events -- at lead times in the order of weeks and months -- may enable reservoir operators to take more effective release decisions to improve the performance of their systems. In practice this might mean a more reliable water supply system, a more profitable hydropower plant or a more sustainable environmental release policy. To this end, climate indices, which represent the oscillation of the ocean-atmospheric system, might be gainfully employed within reservoir operating models that adapt the reservoir operation as a function of the climate condition. This study develops a Stochastic Dynamic Programming (SDP) approach that can incorporate climate indices using a Hidden Markov Model. The model simulates the climatic regime as a hidden state following a Markov chain, with the state transitions driven by variation in climatic indices, such as the Southern Oscillation Index. Time series analysis of recorded streamflow data reveals the parameters of separate autoregressive models that describe the inflow to the reservoir under three representative climate states ("normal", "wet", "dry"). These models then define inflow transition probabilities for use in a classic SDP approach. The key advantage of the Hidden Markov Model is that it allows conditioning the operating policy not only on the reservoir storage and the antecedent inflow, but also on the climate condition, thus potentially allowing adaptability to a broader range of climate conditions. In practice, the reservoir operator would effect a water release tailored to a specific climate state based on available teleconnection data and forecasts. The approach is demonstrated on the operation of a realistic, stylised water reservoir with carry-over capacity in South-East Australia. Here teleconnections relating to both the El Niño Southern Oscillation and the Indian Ocean Dipole influence local hydro-meteorological processes; statistically significant lag correlations have already been established. Simulation of the derived operating policies, which are benchmarked against standard policies conditioned on the reservoir storage and the antecedent inflow, demonstrates the potential of the proposed approach. Future research will further develop the model for sensitivity analysis and regional studies examining the economic value of incorporating long range forecasts into reservoir operation.

  3. Integrated assessment of runoff from concentrated animal feeding operations: Analytical approaches, in vitro bioassays, and in vivo fish exposures

    EPA Science Inventory

    While the trend toward using concentrated animal feeding operations (CAFOs) has resulted in increased efficiency in food production, this has prompted concern regarding the impact these operations have on the environment. For example, animal waste from CAFOs can contain natural a...

  4. Applying an AI Planner to Military Operations Planning

    DTIC Science & Technology

    1993-01-12

    This paper describes a prototype system for quickly developing joint military courses of action. The system, SOCAP (System for Operations Crisis...display and applies this technology to military operations planning. This paper describes the Socap problem domain, how SIPE-2 was used to address this problem, and the strengths and weaknesses of our approach.

  5. 49 CFR 236.207 - Electric lock on hand-operated switch; control.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Electric lock on hand-operated switch; control... switch; control. Electric lock on hand-operated switch shall be controlled so that it cannot be unlocked until control circuits of signals governing movements over such switch have been opened. Approach or...

  6. 49 CFR 236.207 - Electric lock on hand-operated switch; control.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Electric lock on hand-operated switch; control... switch; control. Electric lock on hand-operated switch shall be controlled so that it cannot be unlocked until control circuits of signals governing movements over such switch have been opened. Approach or...

  7. 49 CFR 236.207 - Electric lock on hand-operated switch; control.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Electric lock on hand-operated switch; control... switch; control. Electric lock on hand-operated switch shall be controlled so that it cannot be unlocked until control circuits of signals governing movements over such switch have been opened. Approach or...

  8. Student Registered Nurse Anesthetists' Atittudes toward and Perceptions of Teamwork in the Operating Room

    ERIC Educational Resources Information Center

    Heiner, Jeremy S.

    2013-01-01

    Student registered nurse anesthetists are an important part of an operating room team, yet little research has investigated how they perceive teamwork or approach team related issues specific to the operating room. This mixed methods study evaluated junior and senior student registered nurse anesthetists' attitudes toward and perceptions of…

  9. Applications of Piagetian Theory to the Teaching of Elementary Number Concepts: A Theory-into-Practice Approach.

    ERIC Educational Resources Information Center

    Irmen, Anne

    After a brief description of three Piagetian stages (pre-operational, transition to concrete operations, and concrete operations), the author identifies 12 key statements from Piaget's writings. These statements, together with related implications for teaching elementary school mathematics, methods of diagnosing stage acquisition, and examples are…

  10. Stabilization and reconstruction operations: the role of the US Army Veterinary Corps.

    PubMed

    Smith, John C

    2007-01-01

    Stabilization and reconstruction operations in failed or failing states are vital to US security interests. These operations require a bottom-up approach, focusing on the population as the strategic center of gravity. This bottom-up approach must address the population's basic needs, as defined by Dr Abraham Maslow's hierarchy of needs, and provide a long-term means of self-sufficiency, rather than creating an "aid dependent economy." Focusing operations on agricultural projects provides relief from donor dependency, stimulates economic growth, and thwarts the power of spoilers. US Army Veterinary Corps personnel provide essential services ensuring the procurement of safe and wholesome subsistence and provision of medical care to government-owned animals. Veterinary Corps officers are also uniquely qualified to design and implement agricultural stabilization and reconstruction programs in conjunction with host-state ministries and agencies across the full range of military operations. Early, sustained engagement by veterinarians stimulates agricultural productivity, improves animal and human health, directly supports the population's hierarchy of needs on all levels, and accelerates stabilization operations by reducing the population's susceptibility to spoilers.

  11. Foundations for teaching surgeons to address the contributions of systems to operating room team conflict.

    PubMed

    Rogers, David A; Lingard, Lorelei; Boehler, Margaret L; Espin, Sherry; Schindler, Nancy; Klingensmith, Mary; Mellinger, John D

    2013-09-01

    Prior research has shown that surgeons who effectively manage operating room conflict engage in a problem-solving stage devoted to modifying systems that contribute to team conflict. The purpose of this study was to clarify how systems contributed to operating room team conflict and clarify what surgeons do to modify them. Focus groups of circulating nurses and surgeons were conducted at 5 academic medical centers. Narratives describing the contributions of systems to operating room conflict and behaviors used by surgeons to address those systems were analyzed using the constant comparative approach associated with a constructivist grounded theory approach. Operating room team conflict was affected by 4 systems-related factors: team features, procedural-specific staff training, equipment management systems, and the administrative leadership itself. Effective systems problem solving included advocating for change based on patient safety concerns. The results of this study provide clarity about how systems contribute to operating room conflict and what surgeons can do to effectively modify these systems. This information is foundational material for a conflict management educational program for surgeons. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Robust model-based 3d/3D fusion using sparse matching for minimally invasive surgery.

    PubMed

    Neumann, Dominik; Grbic, Sasa; John, Matthias; Navab, Nassir; Hornegger, Joachim; Ionasec, Razvan

    2013-01-01

    Classical surgery is being disrupted by minimally invasive and transcatheter procedures. As there is no direct view or access to the affected anatomy, advanced imaging techniques such as 3D C-arm CT and C-arm fluoroscopy are routinely used for intra-operative guidance. However, intra-operative modalities have limited image quality of the soft tissue and a reliable assessment of the cardiac anatomy can only be made by injecting contrast agent, which is harmful to the patient and requires complex acquisition protocols. We propose a novel sparse matching approach for fusing high quality pre-operative CT and non-contrasted, non-gated intra-operative C-arm CT by utilizing robust machine learning and numerical optimization techniques. Thus, high-quality patient-specific models can be extracted from the pre-operative CT and mapped to the intra-operative imaging environment to guide minimally invasive procedures. Extensive quantitative experiments demonstrate that our model-based fusion approach has an average execution time of 2.9 s, while the accuracy lies within expert user confidence intervals.

  13. Opportunistic tri-band carrier aggregation in licensed spectrum for multi-operator 5G hetnet

    NASA Astrophysics Data System (ADS)

    Maksymuk, Taras; Kyryk, Maryan; Klymash, Mykhailo; Jo, Minho; Romaniuk, Ryszard; Kotyra, Andrzej; Zhanpeisova, Aizhan; Kozbekova, Ainur

    2017-08-01

    Increasing capacity of mobile networks is a real challenge due to rapid increasing of traffic demands and spectrum scarcity. Carrier aggregation technology is aimed to increase the user data rate by combining the throughput of few spectrum bands, even if they are not physically collocated. Utilization of unlicensed Wi-Fi 5 GHz band for mobile transmission opens new perspectives for carrier aggregation due to vast amount of spectrum range, which can be available for aggregation to supplement data rates for end users. There are many solutions proposed to enable mobile data transmission in unlicensed band without disturbing interference for the existing Wi-Fi users. The paper presents a new approach for opportunistic carrier aggregation in licensed and unlicensed band for multi-operator 5G network. It allows multiple network operators to utilize unlicensed spectrum opportunistically if it is not currently used by Wi-Fi or other mobile network operators. Performance of the proposed approach has been simulated in case of two competing operators. Simulation results reveal that applying the proposed method ensures achieving satisfactory performance of carrier aggregation for the case of two network operators.

  14. Numerical Prediction of CCV in a PFI Engine using a Parallel LES Approach

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

    Ameen, Muhsin M; Mirzaeian, Mohsen; Millo, Federico

    Cycle-to-cycle variability (CCV) is detrimental to IC engine operation and can lead to partial burn, misfire, and knock. Predicting CCV numerically is extremely challenging due to two key reasons. Firstly, high-fidelity methods such as large eddy simulation (LES) are required to accurately resolve the incylinder turbulent flowfield both spatially and temporally. Secondly, CCV is experienced over long timescales and hence the simulations need to be performed for hundreds of consecutive cycles. Ameen et al. (Int. J. Eng. Res., 2017) developed a parallel perturbation model (PPM) approach to dissociate this long time-scale problem into several shorter timescale problems. The strategy ismore » to perform multiple single-cycle simulations in parallel by effectively perturbing the initial velocity field based on the intensity of the in-cylinder turbulence. This strategy was demonstrated for motored engine and it was shown that the mean and variance of the in-cylinder flowfield was captured reasonably well by this approach. In the present study, this PPM approach is extended to simulate the CCV in a fired port-fuel injected (PFI) SI engine. Two operating conditions are considered – a medium CCV operating case corresponding to 2500 rpm and 16 bar BMEP and a low CCV case corresponding to 4000 rpm and 12 bar BMEP. The predictions from this approach are also shown to be similar to the consecutive LES cycles. Both the consecutive and PPM LES cycles are observed to under-predict the variability in the early stage of combustion. The parallel approach slightly underpredicts the cyclic variability at all stages of combustion as compared to the consecutive LES cycles. However, it is shown that the parallel approach is able to predict the coefficient of variation (COV) of the in-cylinder pressure and burn rate related parameters with sufficient accuracy, and is also able to predict the qualitative trends in CCV with changing operating conditions. The convergence of the statistics predicted by the PPM approach with respect to the number of consecutive cycles required for each parallel simulation is also investigated. It is shown that this new approach is able to give accurate predictions of the CCV in fired engines in less than one-tenth of the time required for the conventional approach of simulating consecutive engine cycles.« less

  15. Structural Shielding Design of a 6 MV Flattening Filter Free Linear Accelerator: Indian Scenario.

    PubMed

    Mishra, Bibekananda; Selvam, T Palani; Sharma, P K Dash

    2017-01-01

    Detailed structural shielding of primary and secondary barriers for a 6 MV medical linear accelerator (LINAC) operated with flattening filter (FF) and flattening filter free (FFF) modes are calculated. The calculations have been carried out by two methods, one using the approach given in National Council on Radiation Protection (NCRP) Report No. 151 and the other based on the monitor units (MUs) delivered in clinical practice. Radiation survey of the installations was also carried out. NCRP approach suggests that the primary and secondary barrier thicknesses are higher by 24% and 26%. respectively, for a LINAC operated in FF mode to that of a LINAC operated in both FF and FFF modes with an assumption that only 20% of the workload is shared in FFF mode. Primary and secondary barrier thicknesses calculated from MUs delivered on clinical practice method also show the same trend and are higher by 20% and 19%, respectively, for a LINAC operated in FF mode to that of a LINAC operated in both FF and FFF modes. Overall, the barrier thickness for a LINAC operated in FF mode is higher about 20% to that of a LINAC operated in both FF and FFF modes.

  16. Structural Shielding Design of a 6 MV Flattening Filter Free Linear Accelerator: Indian Scenario

    PubMed Central

    Mishra, Bibekananda; Selvam, T. Palani; Sharma, P. K. Dash

    2017-01-01

    Detailed structural shielding of primary and secondary barriers for a 6 MV medical linear accelerator (LINAC) operated with flattening filter (FF) and flattening filter free (FFF) modes are calculated. The calculations have been carried out by two methods, one using the approach given in National Council on Radiation Protection (NCRP) Report No. 151 and the other based on the monitor units (MUs) delivered in clinical practice. Radiation survey of the installations was also carried out. NCRP approach suggests that the primary and secondary barrier thicknesses are higher by 24% and 26%. respectively, for a LINAC operated in FF mode to that of a LINAC operated in both FF and FFF modes with an assumption that only 20% of the workload is shared in FFF mode. Primary and secondary barrier thicknesses calculated from MUs delivered on clinical practice method also show the same trend and are higher by 20% and 19%, respectively, for a LINAC operated in FF mode to that of a LINAC operated in both FF and FFF modes. Overall, the barrier thickness for a LINAC operated in FF mode is higher about 20% to that of a LINAC operated in both FF and FFF modes. PMID:28405104

  17. Proportional-Integral-Derivative (PID) Temperature Control and Data Acquisition System for Faraday Filter based Sodium Spectrometer

    NASA Astrophysics Data System (ADS)

    Semerjyan, Vardan; Yuan, Tao

    2011-04-01

    Sodium (Na) Faraday filters based spectrometer is a relatively new instrument to study sodium nightglow as well as sodium and oxygen chemistry in the mesopause region. Successful spectrometer measurement demands highly accurate control of filter temperature. The ideal, long-term operation site for the Na spectrometer is an isolated location with minimum nocturnal sky background. Thus, the remote control of the filter temperature is a requirement for such operation, whereas current temperature controllers can only be operated manually. The proposed approach is aimed to not only enhance the temperature control, but also achieve spectrometer's remote and autonomous operation. In the meantime, the redesign should relief the burden of the cost for multi temperature controllers. The program will give to the operator flexibility in setting the operation temperatures of the Faraday filters, monitoring the temperature variations, and logging the data during the operation. Research will make diligent efforts to attach preliminary data analysis subroutine to the main control program. The real-time observation results will be posted online after the observation is completed. This approach also can be a good substitute for the temperature control system currently used to run the Lidar system at Utah State University (USU).

  18. A modular approach for assessing the effect of radiation environments on man in operational systems. The radiobiological vulnerability of man during task performance

    NASA Technical Reports Server (NTRS)

    Ewing, D. E.

    1972-01-01

    A modular approach for assessing the affects of radiation environments on man in operational systems has been developed. The feasibility of the model has been proved and the practicality has been assessed. It has been applied to one operational system to date and information obtained has been submitted to systems analysts and mission planners for the assessment of man's vulnerability and impact on systems survivability. In addition, the model has been developed so that the radiobiological data can be input to a sophisticated man-machine interface model to properly relate the radiobiological stress with other mission stresses including the effects of a degraded system.

  19. OMA analysis of a launcher under operational conditions with time-varying properties

    NASA Astrophysics Data System (ADS)

    Eugeni, M.; Coppotelli, G.; Mastroddi, F.; Gaudenzi, P.; Muller, S.; Troclet, B.

    2018-05-01

    The objective of this paper is the investigation of the capability of operational modal analysis approaches to deal with time-varying system in the low-frequency domain. Specifically, the problem of the identification of the dynamic properties of a launch vehicle, working under actual operative conditions, is studied. Two OMA methods are considered: the frequency-domain decomposition and the Hilbert transform method. It is demonstrated that both OMA approaches allow the time-tracking of modal parameters, namely, natural frequencies, damping ratios, and mode shapes, from the response accelerations only recorded during actual flight tests of a launcher characterized by a large mass variation due to fuel burning typical of the first phase of the flight.

  20. Noise of two high-speed model counter-rotation propellers at takeoff/approach conditions

    NASA Astrophysics Data System (ADS)

    Woodward, Richard P.

    1992-08-01

    This paper presents acoustic results for two model counter-rotation propellers which were tested in the NASA Lewis 9- x 15-ft Anechoic Wind Tunnel. The propellers had a common forward rotor, but the diameter of the aft rotor of the second propeller was reduced in an effort to reduce its interaction with the forward rotor tip vortex. The propellers were tested at Mach 0.20, which is representative of takeoff/approach operation. Acoustic results are presented for these propellers which show the effect of rotor spacing, reduced aft rotor diameter, operation at angle-of-attack, blade loading, and blade number. Limited aerodynamic results are also presented to establish the propeller operating conditions.

  1. Noise of two high-speed model counter-rotation propellers at takeoff/approach conditions

    NASA Technical Reports Server (NTRS)

    Woodward, Richard P.

    1992-01-01

    This paper presents acoustic results for two model counter-rotation propellers which were tested in the NASA Lewis 9- x 15-ft Anechoic Wind Tunnel. The propellers had a common forward rotor, but the diameter of the aft rotor of the second propeller was reduced in an effort to reduce its interaction with the forward rotor tip vortex. The propellers were tested at Mach 0.20, which is representative of takeoff/approach operation. Acoustic results are presented for these propellers which show the effect of rotor spacing, reduced aft rotor diameter, operation at angle-of-attack, blade loading, and blade number. Limited aerodynamic results are also presented to establish the propeller operating conditions.

  2. Limitations Of The Current State Space Modelling Approach In Multistage Machining Processes Due To Operation Variations

    NASA Astrophysics Data System (ADS)

    Abellán-Nebot, J. V.; Liu, J.; Romero, F.

    2009-11-01

    The State Space modelling approach has been recently proposed as an engineering-driven technique for part quality prediction in Multistage Machining Processes (MMP). Current State Space models incorporate fixture and datum variations in the multi-stage variation propagation, without explicitly considering common operation variations such as machine-tool thermal distortions, cutting-tool wear, cutting-tool deflections, etc. This paper shows the limitations of the current State Space model through an experimental case study where the effect of the spindle thermal expansion, cutting-tool flank wear and locator errors are introduced. The paper also discusses the extension of the current State Space model to include operation variations and its potential benefits.

  3. Quiet Short-Haul Research Airplane (QSRA) model select panel functional description

    NASA Technical Reports Server (NTRS)

    Watson, D. M.

    1982-01-01

    The QSRA, when equipped with programmable color cathode ray tube displays, a head up display, a general purpose digital computer and a microwave landing system receiver, will provide a capability to do handling qualities studies and terminal area operating systems experiments as well as to enhance an experimenter's ability to obtain repeatable aircraft performance data. The operating systems experiments include the capability to generate minimum fuel approach and departure paths and to conduct precision approaches to a STOLport runway. The mode select panel is designed to provide both the flexibility needed for a variety of flight test experiments and the minimum workload operation required by pilots flying into congested terminal traffic areas.

  4. MOS 2.0: The Next Generation in Mission Operations Systems

    NASA Technical Reports Server (NTRS)

    Bindschadler, Duane L.; Boyles, Carole A.; Carrion, Carlos; Delp, Chris L.

    2010-01-01

    A Mission Operations System (MOS) or Ground System constitutes that portion of an overall space mission Enterprise that resides here on Earth. Over the past two decades, technological innovations in computing and software technologies have allowed an MOS to support ever more complex missions while consuming a decreasing fraction of Project development budgets. Despite (or perhaps, because of) such successes, it is routine to hear concerns about the cost of MOS development. At the same time, demand continues for Ground Systems which will plan more spacecraft activities with fewer commanding errors, provide scientists and engineers with more autonomous functionality, process and manage larger and more complex data more quickly, all while requiring fewer people to develop, deploy, operate and maintain them. One successful approach to such concerns over this period is a multimission approach, based on the reuse of portions (most often software) developed and used in previous missions. The Advanced Multi-Mission Operations System (AMMOS), developed for deep-space science missions, is one successful example of such an approach. Like many computing-intensive systems, it has grown up in a near-organic fashion from a relatively simple set of tools into a complexly interrelated set of capabilities. Such systems, like a city lacking any concept of urban planning, can and will grow in ways that are neither efficient nor particularly easy to sustain. To meet the growing demands and unyielding constraints placed on ground systems, a new approach is necessary. Under the aegis of a multi-year effort to revitalize the AMMOS's multimission operations capabilities, we are utilizing modern practices in systems architecting and model-based engineering to create the next step in Ground Systems: MOS 2.0. In this paper we outline our work (ongoing and planned) to architect and design a multimission MOS 2.0, describe our goals and measureable objectives, and discuss some of the benefits that this top-down, architectural approach holds for creating a more flexible and capable MOS for Missions while holding the line on cost.

  5. Beyond cost-of-energy, the value-of-energy metric and value-centric approaches to design, operations, and maintenance of wind turbines

    NASA Astrophysics Data System (ADS)

    Fernandes, Kevin

    This thesis is oriented toward developers, owners, operators and investors of renewable energy projects. With increasing demand of renewables, our energy dependence comes down to reducing costs associated with this sector so as to compete with the existing sources. One way of valuing investment potential is to determine and then compare the overall value derived by investing in a particular project. Several engineering and financial levers, one of which is operation and maintenance, affect this value. This thesis provides a useful visual aid to owners and operators by which they can operate and maintain their wind farm so as to achieve maximum value throughout its lifetime. All the necessary components that go into developing a business model of a wind farm project will be discussed. Finally, this tool is valid within the assumptions that are explicitly stated. Real world data and trends are used to provide a practical approach to the optimization.

  6. Operational management of offshore energy assets

    NASA Astrophysics Data System (ADS)

    Kolios, A. J.; Martinez Luengo, M.

    2016-02-01

    Energy assets and especially those deployed offshore are subject to a variety of harsh operational and environmental conditions which lead to deterioration of their performance and structural capacity over time. The aim of reduction of CAPEX in new installations shifts focus to operational management to monitor and assess performance of critical assets ensuring their fitness for service throughout their service life and also to provide appropriate and effective information towards requalification or other end of life scenarios, optimizing the OPEX. Over the last decades, the offshore oil & gas industry has developed and applied various approaches in operational management of assets through Structural Health and Condition Monitoring (SHM/CM) systems which can be, at a certain level, transferable to offshore renewable installations. This paper aims to highlight the key differences between offshore oil & gas and renewable energy assets from a structural integrity and reliability perspective, provide a comprehensive overview of different approaches that are available and applicable, and distinguish the benefits of such systems in the efficient operation of offshore energy assets.

  7. The determination of effective injury controls for metal-cutting lathe operators.

    PubMed

    Etherton, J R; Trump, T R; Jensen, R C

    1981-01-01

    Operators of metal-working lathes are one of the largest manufacturing machine worker populations in the United States. Machines (other than vehicular) account for over 10% of occupational injuries each year. An estimated 3,400 operators of metal-working lathes suffer lost-time injuries annually in the United States. Some of these are fatal. Therefore an investigation was undertaken to determine methods for reducing injuries to lathe operators. Three methods were used: (i) review of injury reports, (ii) human factors analysis, and (iii) fault-tree procedures. The investigation followed the man-machine systems approach of looking for injury-producing dysfunctions between the lathe and the lathe operator. The major sources of injury were found to be chips and workholding devices. Secondary tasks were found to be more hazardous than is generally recognized. The use of three methods for approaching the problem was found to be useful in that injury controls were identified which are likely to be adopted because of their potential for improving safety without adversely affecting productivity.

  8. Tactical physical preparation: the case for a movement-based approach.

    PubMed

    Kechijian, Doug; Rush, Stephen

    2012-01-01

    Progressive injury prevention and physical preparation programs are needed in military special operations to optimize mission success and Operator quality of life and longevity. While physical risk is inherent in Special Operations, non-traumatic injuries resulting from overuse, poor biomechanics, and arbitrary exercise selection can be alleviated with proper medical care and patient education. An integrated approach to physical readiness that recognizes the continuity between rehabilitation and performance training is advocated to ensure that physiological adaptations do not come at the expense of orthopedic health or movement proficiency. Movement quality should be regularly evaluated and enforced throughout the training process to minimize preventable injuries and avoid undermining previous rehabilitative care. While fitness and proper movement are not substitutes for Operator specific tasks, they are foundational to many tactically-relevant skills. In light of how much is at stake, sports medicine care in the military, especially special operations, should parallel that which is practiced in professional and collegiate athletics. 2012.

  9. Operationally Efficient Propulsion System Study (OEPSS) data book. Volume 3: Operations technology

    NASA Technical Reports Server (NTRS)

    Vilja, John O.

    1990-01-01

    The study was initiated to identify operational problems and cost drivers for current propulsion systems and to identify technology and design approaches to increase the operational efficiency and reduce operations costs for future propulsion systems. To provide readily usable data for the Advanced Launch System (ALS) program, the results of the OEPSS study were organized into a series of OEPSS Data Books. This volume describes operations technologies that will enhance operational efficiency of propulsion systems. A total of 15 operations technologies were identified that will eliminate or mitigate operations problems described in Volume 2. A recommended development plan is presented for eight promising technologies that will simplify the propulsion system and reduce operational requirements.

  10. Mentoring SFRM: A New Approach to International Space Station Flight Controller Training

    NASA Technical Reports Server (NTRS)

    Huning, Therese; Barshi, Immanuel; Schmidt, Lacey

    2008-01-01

    The Mission Operations Directorate (MOD) of the Johnson Space Center is responsible for providing continuous operations support for the International Space Station (ISS). Operations support requires flight controllers who are skilled in team performance as well as the technical operations of the ISS. Space Flight Resource Management (SFRM), a NASA adapted variant of Crew Resource Management (CRM), is the competency model used in the MOD. ISS flight controller certification has evolved to include a balanced focus on development of SFRM and technical expertise. The latest challenge the MOD faces is how to certify an ISS flight controller (operator) to a basic level of effectiveness in 1 year. SFRM training uses a two-pronged approach to expediting operator certification: 1) imbed SFRM skills training into all operator technical training and 2) use senior flight controllers as mentors. This paper focuses on how the MOD uses senior flight controllers as mentors to train SFRM skills. Methods: A mentor works with an operator throughout the training flow. Inserted into the training flow are guided-discussion sessions and on-the-job observation opportunities focusing on specific SFRM skills, including: situational leadership, conflict management, stress management, cross-cultural awareness, self care and team care while on-console, communication, workload management, and situation awareness. The mentor and operator discuss the science and art behind the skills, cultural effects on skills applications, recognition of good and bad skills applications, recognition of how skills application changes subtly in different situations, and individual goals and techniques for improving skills. Discussion: This mentoring program provides an additional means of transferring SFRM knowledge compared to traditional CRM training programs. Our future endeavors in training SFRM skills (as well as other organization s) may benefit from adding team performance skills mentoring. This paper explains our mentoring approach and discusses its effectiveness and future applicability in promoting SFRM/CRM skills.

  11. Genito-Urinary Function and Quality of Life after Elective Totally Laparoscopic Sigmoidectomy after at Least One Episode of Complicated Diverticular Disease According to Two Different Vascular Approaches: the IMA Low Ligation or the IMA Preservation.

    PubMed

    Mari, Giulio; Crippa, Jacopo; Costanzi, Andrea; Mazzola, Michele; Magistro, Carmelo; Ferrari, Giovanni; Maggioni, Dario

    2017-01-01

    The arterial ligation during elective laparoscopic sigmoidectomy for diverticular disease can affect genito-urinary function injuring the superior hypogastric plexus, and can weaken the distal colonic stump arterial perfusion. Ligation of the inferior mesenteric artery distal to the left colic artery or the complete preservation of the inferior mesenteric artery can therefore be compared in terms of preservation of the descending sympathetic fibres running along the aorta to the rectum resulting in a different post operative genito urinary function. From January 2015 to March 2016, 66 patients underwent elective laparoscopic sigmoidectomy for diverticular disease among two enrolling hospitals. In one centre 35 patients underwent laparoscopic sigmoidectomy with the ligation of the inferior mesenteric artery distal to the left colic artery (low ligation). In the other centre 31 patient were operated on the same procedure with complete inferior mesenteric artery preservation (IMA preservation). There was no difference in terms of major complication occurred, first passage of stool and length of hospital stay between the two groups. Time of surgery was significantly shorter in LL group compared to IMA preserving group and intra operative blood loss was significantly lower in the LL group. There were no differences in the genito urinary function between the two group pre operatively, at 1 and 9 months post operatively. Genito urinary function did not significantly change across surgery in each groups. The low ligation and the IMA preserving vascular approach are safe end feasible techniques in elective laparoscopic sigmoidectomy for diverticular disease. They both prevent from genito-urinary post-operative disfunction and allow good post operative quality of life. The low ligation approach is related to shorter operative time and slower intra operative blood loss. Celsius.

  12. Mars 2001 Lander Mission: Measurement Synergy through Coordinated Operations Planning and Implementation

    NASA Astrophysics Data System (ADS)

    Arvidson, R.; Bell, J. F., III; Kaplan, D.; Marshall, J.; Mishkin, A.; Saunders, S.; Smith, P.; Squyres, S.

    1999-03-01

    The Science Operations Working Group, Mars 2001 Mission, has developed coordinated plans for scientific observations that treat the instruments as an integrated payload. This approach ensures maximum return of scientific information.

  13. Real-Time CORBA

    DTIC Science & Technology

    2000-10-01

    control systems and prototyped the approach by porting the ILU ORB from Xerox to the Lynx real - time operating system . They then provided a distributed...compliant real - time operating system , a real-time ORB, and an ODMG-compliant real-time ODBMS [12]. The MITRE system is an infrastructure for...the server’s local operating system can handle. For instance, on a node controlled by the VXWorks real - time operating system with 256 local

  14. Chaplain Roles in Humanitarian and Civic Assistance Operations

    DTIC Science & Technology

    1994-04-08

    the relationship of military chaplains to civilians in disaster relief operations and their role as clergy when approached by civilians requesting...legal issues, the roles of other players, and Army doctrine on operations other than war. This paper reviews chaplain ministry and duty performance... the roles of other players, and Army doctrine on operations other than war. This paper reviews chaplain ministry and duty performance during four HCA

  15. A differential operator realisation approach for constructing Casimir operators of non-semisimple Lie algebras

    NASA Astrophysics Data System (ADS)

    Alshammari, Fahad; Isaac, Phillip S.; Marquette, Ian

    2018-02-01

    We introduce a search algorithm that utilises differential operator realisations to find polynomial Casimir operators of Lie algebras. To demonstrate the algorithm, we look at two classes of examples: (1) the model filiform Lie algebras and (2) the Schrödinger Lie algebras. We find that an abstract form of dimensional analysis assists us in our algorithm, and greatly reduces the complexity of the problem.

  16. Preventing musculoskeletal disorders in clinical dentistry: strategies to address the mechanisms leading to musculoskeletal disorders.

    PubMed

    Valachi, Bethany; Valachi, Keith

    2003-12-01

    The authors reviewed studies to identify methods for dental operators to use to prevent the development of musculoskeletal disorders, or MSDs. The authors reviewed studies that related to the prevention of MSDs among dental operators. Some studies investigated the relationship between the biomechanics of seated working postures and physiological damage or pain. Other studies suggested that repeated unidirectional twisting of the trunk can lead to low back pain, while yet other studies examined the detrimental effects of working in one position for prolonged periods. Additional studies confirmed the roles that operators' flexibility and core strength can play in balanced musculoskeletal health and the need for operators to know how to properly adjust ergonomic equipment. This review indicates that strategies to prevent the multifactorial problem of dental operators' developing MSDs exist. These strategies address deficiencies in operator position, posture, flexibility, strength and ergonomics. Education and additional research are needed to promote an understanding of the complexity of the problem and to address the problem's multifactorial nature. A comprehensive approach to address the problem of MSDs in dentistry represents a paradigm shift in how operators work. New educational models that incorporate a multifactorial approach can be developed to help dental operators manage and prevent MSDs effectively.

  17. Results of prototype software development for automation of shuttle proximity operations

    NASA Technical Reports Server (NTRS)

    Hiers, Hal; Olszweski, Oscar

    1991-01-01

    The effort involves demonstration of expert system technology application to Shuttle rendezvous operations in a high-fidelity, real-time simulation environment. The JSC Systems Engineering Simulator (SES) served as the test bed for the demonstration. Rendezvous applications were focused on crew procedures and monitoring of sensor health and trajectory status. Proximity operations applications were focused on monitoring, crew advisory, and control of the approach trajectory. Guidance, Navigation, and Control areas of emphasis included the approach, transition and stationkeeping guidance, and laser docking sensor navigation. Operator interface displays for monitor and control functions were developed. A rule-based expert system was developed to manage the relative navigation system/sensors for nominal operations and simple failure contingencies. Testing resulted in the following findings; (1) the developed guidance is applicable for operations with LVLH stabilized targets; (2) closing rates less than 0.05 feet per second are difficult to maintain due to the Shuttle translational/rotational cross-coupling; (3) automated operations result in reduced propellant consumption and plume impingement effects on the target as compared to manual operations; and (4) braking gates are beneficial for trajectory management. A versatile guidance design was demonstrated. An accurate proximity operations sensor/navigation system to provide relative attitude information within 30 feet is required and redesign of the existing Shuttle digital autopilot should be considered to reduce the cross-coupling effects. This activity has demonstrated the feasibility of automated Shuttle proximity operations with the Space Station Freedom. Indications are that berthing operations as well as docking can be supported.

  18. Operator function modeling: An approach to cognitive task analysis in supervisory control systems

    NASA Technical Reports Server (NTRS)

    Mitchell, Christine M.

    1987-01-01

    In a study of models of operators in complex, automated space systems, an operator function model (OFM) methodology was extended to represent cognitive as well as manual operator activities. Development continued on a software tool called OFMdraw, which facilitates construction of an OFM by permitting construction of a heterarchic network of nodes and arcs. Emphasis was placed on development of OFMspert, an expert system designed both to model human operation and to assist real human operators. The system uses a blackboard method of problem solving to make an on-line representation of operator intentions, called ACTIN (actions interpreter).

  19. A New Tool for Environmental and Economic Optimization of Hydropower Operations

    NASA Astrophysics Data System (ADS)

    Saha, S.; Hayse, J. W.

    2012-12-01

    As part of a project funded by the U.S. Department of Energy, researchers from Argonne, Oak Ridge, Pacific Northwest, and Sandia National Laboratories collaborated on the development of an integrated toolset to enhance hydropower operational decisions related to economic value and environmental performance. As part of this effort, we developed an analytical approach (Index of River Functionality, IRF) and an associated software tool to evaluate how well discharge regimes achieve ecosystem management goals for hydropower facilities. This approach defines site-specific environmental objectives using relationships between environmental metrics and hydropower-influenced flow characteristics (e.g., discharge or temperature), with consideration given to seasonal timing, duration, and return frequency requirements for the environmental objectives. The IRF approach evaluates the degree to which an operational regime meets each objective and produces a score representing how well that regime meets the overall set of defined objectives. When integrated with other components in the toolset that are used to plan hydropower operations based upon hydrologic forecasts and various constraints on operations, the IRF approach allows an optimal release pattern to be developed based upon tradeoffs between environmental performance and economic value. We tested the toolset prototype to generate a virtual planning operation for a hydropower facility located in the Upper Colorado River basin as a demonstration exercise. We conducted planning as if looking five months into the future using data for the recently concluded 2012 water year. The environmental objectives for this demonstration were related to spawning and nursery habitat for endangered fishes using metrics associated with maintenance of instream habitat and reconnection of the main channel with floodplain wetlands in a representative reach of the river. We also applied existing mandatory operational constraints for the facility during the demonstration. We compared the optimized virtual operation identified by the toolset to actual operations at the facility for the same time period to evaluate implications of the optimized operational regime on power/revenue generation and environmental performance. Argonne National Laboratory's work was part of a larger "Water-Use-Optimization" project supported by the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy, Water Power Program, under Announcement DE-FOA-0000070. The submitted manuscript has been created by UChicago Argonne, LLC, Operator of Argonne National Laboratory ("Argonne"). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357. The U.S. Government retains for itself, and others acting on its behalf, a paid-up nonexclusive, irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the Government.

  20. Cryogenic parallel, single phase flows: an analytical approach

    NASA Astrophysics Data System (ADS)

    Eichhorn, R.

    2017-02-01

    Managing the cryogenic flows inside a state-of-the-art accelerator cryomodule has become a demanding endeavour: In order to build highly efficient modules, all heat transfers are usually intercepted at various temperatures. For a multi-cavity module, operated at 1.8 K, this requires intercepts at 4 K and at 80 K at different locations with sometimes strongly varying heat loads which for simplicity reasons are operated in parallel. This contribution will describe an analytical approach, based on optimization theories.

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